Critical Care Obstetrics part 28 doc

Cardiac Disease
259
100
75
50
25
0
% change in cardiac output
Pre Early Mid- Late Second Immed. 10 min 1 h
First stage
Stage
Postpartum
During contractions
Between contractions
Figure 20.2 Fluctuations in cardiac output
associated with normal labor, delivery, and
postpartum. (Reproduced by permission from
Bonica JJ, McDonald JS.
Principles and Practice of
Obstetrics Analgesia and Anesthesia
, 2nd edn.
Lippincott, Williams & Wilkins, 1994.)
Table 20.4 Coagulation factors and inhibitors during normal pregnancy.
Factor Non - pregnant Late pregnancy
Factor I (fi brinogen) 200 – 450mg/dL 400 – 650mg/dL
Factor II (prothrombin) 75 – 125% 100 – 125%
Factor V 75 – 125% 100 – 150%
Factor VII 75 – 125% 150 – 250%
Factor VIII 75 – 150% 200 – 500%
Factor IX 75 – 125% 100 – 150%
Factor X 75 – 125% 150 – 250%

Factor XI 5 – 125% 50 – 100%
Factor XII 75 – 125% 100 – 200%
Factor XIII 75 – 125% 35 – 75%
Antithrombin III 85 – 110% 75 – 100%
Antifactor Xa 85 – 110% 75 – 100%
(Reprinted by permission from Hathaway WE, Bonnar J. Coagulation in
pregnancy. In: Hathaway WE, Bonnar J, eds. Perinatal Coagulation. New York:
Grune & Stratton, 1978.)
some cases, an additional 50% by the late second stage. The
potential for further dramatic volume shifts occurs around the
time of delivery, both secondary to postpartum hemorrhage and
as the result of an “ autotransfusion ” occurring with release of
vena caval obstruction and sustained uterine contraction. Such
volume shifts may be poorly tolerated by women whose cardiac
output is highly dependent on adequate preload (pulmonary
hypertension) or in those with fi xed cardiac output (mitral ste-
nosis). Figure 20.2 illustrates the marked fl uctuations in cardiac
output associated with normal labor, delivery, and postpartum
[17] .
The risk classifi cation presented in Table 20.2 assumes clean
delineation of various cardiovascular lesions. Unfortunately, in
actual practice this is only rarely the case. Optimal management
of a patient with any specifi c combination of lesions requires a
thorough assessment of the anatomic and functional capacity of
the heart, followed by an analysis of how the physiologic changes
described previously will impact on the specifi c anatomic or
physiologic limitations imposed by the intrinsic disease. Such an
analysis will allow a prioritization of often confl icting physiologic
demands and greatly assist the clinician in avoiding or managing
potential complications.

Certain management principles generally apply to most
patients with cardiac disease. These include the judicious use of
antepartum bed rest and meticulous prenatal care. Intrapartum
management principles include laboring in the lateral position;
the use of epidural anesthesia, which will minimize intrapartum
fl uctuations in cardiac output (although the use of epidural nar-
cotic rather than epidural local anesthesia may be more appro-
priate for patients with certain types of cardiac lesions); the
administration of oxygen; and endocarditis prophylaxis, when
appropriate. Positional effects on maternal cardiac output during
labor with epidural analgesia have recently been detailed [18] .
Additional management recommendations may vary according
to the specifi c lesion present. For patients with signifi cant cardiac
disease, management and delivery in a referral center is recom-
mended. In many cases, management with peripheral pulse
oximetry is replacing invasive hemodynamic monitoring.
Congenital c ardiac l esions
As previously discussed, the relative frequency of congenital as
opposed to acquired heart disease is changing [2,7,19,20] .
Rheumatic fever is less common in the United States, and more
patients with congenital cardiac disease now survive to reproduc-
Chapter 20
260
anesthesia are means to reduce cardiac work. All ASDs have some
degree of right to left shunting, particularly with valsalva - type
maneuvers. Hence, consideration of air trap fi lters applied to IV
lines should be considered to reduce this possibility. New recom-
mendations regarding the use of antiobiotic prophylaxis for pre-
vention of bacterial endocarditis have recently been published
[28] . The American Heart Association does not recommend anti-

biotic prophylaxis for secundum atrial septal defects. Further
discussion regarding the latest recommendations antiobiotic pro-
phylaxis against bacterial endocarditis for congenital heart defects
is found later in this chapter and in Table 20.5 .
Ventricular s eptal d efect
Ventricular septal defect may occur as an isolated lesion or in
conjunction with other congenital cardiac anomalies, including
tetralogy of Fallot, transposition of the great vessels, and coarcta-
tion of the aorta. The size and location of the septal defect is the
most important determinant of clinical prognosis during preg-
nancy. Small defects are tolerated well, while larger defects are
associated more frequently with congestive failure, arrhythmias,
or the development of pulmonary hypertension. Those VSDs that
are associated with other congenital anomalies may be much
more complicated and can be associated with much higher risk
of heart failure, arrhythmia, cyanosis or pulmonary hypertension,
depending on the lesion type, prior surgery and residual lesions
after surgical repair. In general, pregnancy, labor, and delivery are
generally well tolerated by patients with an uncomplicated VSD.
Schaefer et al. [25] compiled a series of 141 pregnancies in 56
women with VSD. The only two maternal deaths were in women
whose VSD was complicated by pulmonary hypertension
(Eisenmenger ’ s syndrome). Because of the high risk of death
associated with unrecognized pulmonary hypertension, echocar-
diography or cardiac catheterization is essential in any adult
patient in whom persistent VSD is suspected, or in whom the
quality or success of the previous repair is uncertain [29,30] .
The primary closure of a moderately restrictive or non -
restrictive VSD in early childhood usually prevents the
tive age. In a review in 1954, the ratio of rheumatic to congenital

heart disease seen during pregnancy was 16 : 1; by 1967, this ratio
had changed to 3 : 1 [19 – 21] . A more recent report from Taiwan
suggested a rheumatic/congenital cardiac ratio of 1 : 1.5 during
pregnancy [7] . Similarly, in the United Kingdom between 1973
and 1987, the number of deaths from congenital heart disease has
doubled, whereas the number of deaths from rhuematic heart
disease has halved [2] . In the subsequent discussion of specifi c
cardiac lesions, no attempt will be made to duplicate existing
comprehensive texts regarding physical diagnostic, electrocardio-
graphic, and radiographic fi ndings of specifi c cardiac lesions.
Rather, the discussion presented here focuses on aspects of
cardiac disease that are unique to pregnancy.
Atrial s eptal d efect
Secundum atrial septal defect (ASD) is the most common repaired
and unrepaired congenital lesion that occurs in pregnant woment,
and, in general, it is asymptomatic and well tolerated even in
those with large left to right shunts [22 – 24] . The three signifi cant
potential complications seen with ASD are arrhythmias, heart
failure and “ paradoxical embolism ” . Although atrial arrhythmias
are not uncommon in patients with ASD, their onset generally
occurs after the fourth decade of life; thus, such arrhythmias,
however unlikely, are becoming more of a concern with the
recent prevalence of delayed childbearing. In patients with ASD,
atrial fi brillation is the most common arrhythmia encountered;
however, supraventricular tachycardia and atrial fl utter also may
occur. Antiarrythmic or rate - controlling agents or other medica-
tions may be indicated for symptomatic patients with these
arrhythmias and in some, cardioversion may be necessary (see
section on dysrrhythmia).
The hypervolemia associated with pregnancy results in an

increased left to right shunt through the ASD, and, thus, a sig-
nifi cant burden is imposed on the right atrium, right ventricle
and pulmonary vasculature. Although this additional burden is
tolerated well by most patients, congestive heart failure and death
with ASD have been reported [25 – 27] . In contrast to VSD or
PDA, large left to right shunts at the atrial level do not usually
result in pulmonary hypertension or even irreversible pulmonary
hypertension at childbearing age.
An extremely rare and unusual potential complication that
exists with ASD is “ paradoxical embolization. ” If this occurs, it is
most likely as a result of venous thrombosis but can be air or
amniotic in the pregnant woman. Thromboemboli from leg or
pelvic veins may be directed across the ASD into the systemic
circulation, “ paradoxically, ” resulting in ischemic neurologic
complications such as transient ischemic attack (TIA) or stroke
or other arterial ischemic complications.
The vast majority of patients with ASD, however, tolerate preg-
nancy, labor, and delivery without complication. Neilson et al.
[26] reported 70 pregnancies in 24 patients with ASD; all patients
had an uncomplicated ante - and intrapartum course. During
labor, avoidance of fl uid overload, oxygen administration, labor
in the lateral recumbent position, and pain relief with epidural
Table 20.5 Guidelines from the AHA 2007 Prevetion of infective endocarditis:
Patients with highest risk of adverse outcomes from endocarditis.
1. Prosthetic cardiac valves (mechanical, bioprosthetic, homograft)
2. Previous history of infective endocarditis
3. Unrepaired cyanotic congenital heart disease, including palliative shunts and
conduits
4. Completely repaired congenital heart defects with prosthetic material or
device, surgically or interventionally placed, during the fi rst 6 months after

the procedure
5. Repaired CHD with residual defects at the site or adjacent to the site of a
prosthetic patch or prosthetic device
6. Cardiac transplanted heart with signifi cant valvulopathy (leafl et pathology
and regurgitation)
Adapted from: Wilson W. et al. 2007.
Cardiac Disease
261
outcomes are generally favorable. However, in those patients
found to have irreversible pulmonary hypertension such as those
with equivalent systemic and pulmonary artery pressures, cyano-
sis or bidirectional shunting, the prognosis during pregnancy is
extremely grave.
Eisenmenger ’ s syndrome consists of congenital systemic arte-
rial to systemic venous shunt (left to right shunt), development
of pulmonary hypertension and shunt reversal with bidirectional
shunting/or cyanosis. This syndrome may occur from a variety
of common congenital lesions including VSD, ASD, PDA and
more complex anatomic disorders. The risk of developing pulm-
ononary hypertension and Eisenmenger ’ s syndrome from con-
genital shunts is determined by the the type of shunt and degree
of left to right shunt as noted above. Whatever the etiology,
development of irreversible pulmonary hypertension or
Eisenmenger ’ s syndrome during prengnacy portends a poor
prognosis. During the antepartun period, decreased systemic vas-
cular resistance increases right to left shunting, acidosis and
hypotension. With systemic hypotension against a fi xed pulmo-
nary vascular resistance the degree of right to left shunting and
hypoxia further increases, with a vicious spiraling circle of
hypotension, cyanosis, hypoxia and ultimate death.

Such hypotension can result from hemorrhage or complica-
tions of conduction anesthesia and may result in sudden death
[32 – 35] . Avoidance of such hypotension is the principal clinical
concern in the intrapartum management of patients with pulmo-
nary hypertension of any etiology.
Maternal mortality in the presence of Eisenmenger ’ s syndrome
is reported as 30 – 50% [26,27,30,31] . In a review of the subject,
Gleicher et al. [33] reported a 34% mortality associated with
vaginal delivery and a 75% mortality associated with cesarean
section. In a more recent report, Weiss et al. [36] reviewed the
published literature from 1978 to 1996 investigating Eisenmenger ’ s
syndrome, primary pulmonary hypertension and secondary pul-
monary hypertension during pregnancy. Despite advances in
maternal and cardiac care during this interval, the overall com-
posite mortality rate for Eisenmenger ’ s syndrome during preg-
nancy remained 36% – relatively unchanged for the last two
decades [37 – 41] . In this series, however, there appeared to be
little difference in mortality when comparing vaginal delivery
(48%) to cesarean section (52%). These investigators also con-
cluded that maternal prognosis depended on the early diagnosis
of pulmonary vascular disease during pregnancy, early hospital
admission, and individually tailored treatment during pregnancy
with specifi c attention focused on the postpartum period. Table
20.6 reviews the management and outcome of pregnant women
with Eisenmenger ’ s syndrome [36] . In addition to the previously
discussed problems associated with hemorrhage and hypovole-
mia, thromboembolic phenomena have been associated with up
to 43% of all maternal deaths in Eisenmenger ’ s syndrome [33] .
In the more recent report by Weiss et al. [36] , however, pulmo-
nary thromboembolism accounted for only 3 of the 26 (12%)

maternal deaths in this composite analysis. Sudden delayed post-
partum death, occurring 4 – 6 weeks after delivery, also has been
subsequent development of secondary pulmonary vascular
hypertension and therefore permits an uneventful pregnancy.
Fortunately, signifi cant postoperative electrophysiologic conduc-
tion abnormalities are rarely encountered.
Although very rarely indicated, successful primary closures of
VSDs during pregnancy have been reported. Intrapartum man-
agement considerations for patients with uncomplicated VSD or
PDA are similar to those outlined for ASD. In general, invasive
hemodynamic monitoring is usually unnecessary.
Patent d uctus a rteriosus
Although patent ductus arteriosus (PDA) is one of the most
common congenital cardiac anomalies, its almost universal
detection and closure in the newborn period makes it uncommon
during pregnancy [20] . As with uncomplicated ASD and VSD,
most patients are asymptomatic, and PDA is generally well toler-
ated during pregnancy, labor, and delivery. As with a large VSD,
however, the high - pressure – high - fl ow left to right shunt associ-
ated with a large, uncorrected PDA can lead to pulmonary hyper-
tension. In such cases, the prognosis becomes much worse since
shunt reversal can occur with fall in systemic vascular resistance
during pregnancy, delivery and early postpartum leading to a
spiraling cycle of cyanosis, acidosis and hypotension. In one study
of 18 pregnant women who died of congenital heart disease, three
had PDA; however, all of these patients had severe secondary
pulmonary hypertension [27] . In most circumstances, however,
an asymptomatic young woman with a small or moderate - sized
PDA, without pulmonary hypertension, will have a relatively
uncomplicated pregnancy. Apart from a single case report of a

spontaneous postpartum rupture of a PDA, in a patient with
normal pulmonary pressure and without ductal aneurysm [31] ,
the risks are minimal.
Pulmonary h ypertension and Eisenmenger ’ s s yndrome
As discussed in the previous section, women with secundum ASD
rarely manifest pulmonary hypertension in the childbearing age
range and those with VSD or PDA are more likely to develop
pulmonary hypertension compared to those with ASD. Patients
with left to right shunts may have a continuum of progressive
pulmonary artery pressure elevation and varying degrees of
reversibility. It should be of note that with large left to right
shunts, echocardiographic studies may suggest the presence of
pulmonary artery systolic hypertension. Elevated pulmonary
artery systolic pressures can be seen with high fl ow states in left
to right shunts and should not be confused with irreversible
pulmonary hypertension. Degree of left to right shunting and
degree of pulmonary artery hypertension reversibility can usually
be assessed before pregnancy or even during pregnancy with
clinical evaluation, echocardiography along with other laboratory
tests. A general rule of thumb is that pulmonary artery systolic
hypertension in association with a left to right shunt of 1 : 5 : 1 or
higher has some reversibility, otherwise, there would be no
capcity for shunting. In these patients, in the absence of profound
uncompensated left heart failure from volume overload, maternal
Chapter 20
262
hypertension, and the pregnancy is desired, pulmonary artery
catheterization with direct measurement of pulmonary artery
pressures may be performed on an outpatient basis in early preg-
nancy. This can be done with no to minimal radiation exposure

in experienced hands using a brachial or internal jugular
approach. Where signifi cant fi xed irreversible pulmonary hyper-
tension exists, pregnancy termination in either the fi rst or second
trimester appears to be safer than allowing the pregnancy to
progress to term [44] . Dilation and curettage in the fi rst trimester
or dilation and evacuation in the second trimester are the methods
of choice. Hypertonic saline and F - series prostaglandins are con-
traindicated, the latter due to arterial oxygen desaturation seen
with the use of this agent [45] . Prostaglandin E
2
suppositories
appear to be safe under these circumstances.
It is highly recommended that the woman with signifi cant
pulmonary hypertension/Eisenmenger ’ s syndrome who elects to
continue pregnancy undergoes hospitalization for the duration
of pregnancy. Alternatively very close clinical follow - up and early
hospitalization at a center specialized in treatment of this condi-
tion at the fi rst sign or detection of clinical deterioration may be
considered on a case - by - case basis. Continuous administration of
oxygen, the pulmonary vasodilator of choice, is suggested and
may improve perinatal outcome. Consideration of anticoagula-
tion in the peripartum period has been suggested as a method to
lower this risk but there has been concern that this may instead
contribute to a fatal outcome. Patients with Eisenmenger ’ s syn-
drome have abnormalities with coagulation factors, and with
platelet function and number. The very real possibility of fatal
intrapulmonary hemorrhage and hemoptysis while on anticoagu-
lants has to be weighed against the possible risk of suspected
peripartum thromboembolism as the cause of death in these
patients during the third trimester and postpartum. Since death

has been reported with fatal hemorrhaging while on anticoagu-
lants and benefi t of this therapy is not proven, routine endorse-
ment of this treatment modality cannot be given.
In cyanotic heart disease of any etiology, fetal outcome corre-
lates well with maternal hemoglobin, and successful pregnancy is
unlikely with a hemoglobin greater than 20 g/dL [13] . Maternal
P
a
O
2
should be maintained at a level of 70 mmHg or above [46] .
Third - trimester fetal surveillance with antepartum testing is
important because at least 30% of the fetuses will suffer growth
restriction [33] . Although the overall fetal wastage with
Eisenmenger ’ s syndrome is reported to be up to 75%, more
recent information suggests a more favorable outcome. Weiss
et al. reported a neonatal survival rate of nearly 90% in cases
of Eisenmenger ’ s syndrome. Unfortunately, since only late
pregnancy cases were reviewed, no conclusions can be drawn
about the rate of early fetal wastage.
For pregnant patients with Eisenmenger ’ s syndrome some
experts previously advocated placement of a Swan – Ganz catheter
in the intrapartum period in an effort to minimize changes in
cardiovascular hemodynamics, cyanosis and the shunt that
occurs with uterine contractions [47] . However, placement and
stabilization of a right heart catheter in a pulmonary artery
reported [33,36,42] . Such deaths may involve a rebound worsen-
ing of pulmonary hypertension associated with the loss of preg-
nancy - associated hormones, which leads to decreased pulmonary
vascular resistance during gestation [17] .

Caution should be exercised when evaluating for the presence
of pulmonary hypertension with non - invasive techniques such as
Doppler/two - dimensional echocardiogram. The assumptions
used by many cardiologists for assessment of pulmonary pres-
sures do not take into account viscosity (Hb) nor pregnant state
when assessing the tricuspid jet or estimating the right atrial pres-
sure based on IVC size. The ordering physician should directly
communicate with the interpreting physician these issues when
trying to determine pulmonary artery pressures since other
methods to assess these values may be available. Otherwise, these
techniques have a clear tendency to signifi cantly overestimate the
degree of pulmonary hypertension during pregnancy and may
incorrectly diagnose the presence of pulmonary hypertension in
up to 32% of cases when compared with cardiac catheterization
[43] . If any question exists regarding the presence of pulmonary
Table 20.6 Management and outcome of pregnant women with Eisenmenger ’ s
syndrome (
n
= 73).
Maternal
survival
Maternal
mortality
Number (%) 47 (64%) 26 (36%)
Age (years)
26.4 ± 4.8 24.9 ± 4.5
Hospital admission (weeks of pregnancy)
26.7 ± 6.5 31.4 ± 5.9
Toxemia of pregnancy 2 (4%) 3 (12%)
Delivery (weeks of pregnancy)

35.1 ± 3.5 34.4 ± 4.4
Vaginal delivery 27 (57%) 11 (48%)
Operative delivery 20 (43%) 12 (52%)
Monitoring
Non - invasive, not reported 24 (51%) 15 (63%)
Invasive SAP and/or CVP 23 (49%) 9 (37%)
Invasive PAP 8 (17%) 6 (25%)
Anesthesia/analgesia
Not reported 13 (28%) 5 (22%)
Regional techniques 22 (47%) 8 (35%)
General anesthesia 12 (25%) 7 (30%)
Local anesthesia/analgesia 0 3 (13%)
Oxytocic drugs 14 (30%) 4 (17%)
Antithrombotic therapy 28 (60%) 12 (46%)
Neonatal survival 43 (96%) * 20 (77%)
Maternal death, days postpartum – 5 (0 – 30)
Data presented are mean value; ± SD, number (%) of patients, or median
(range).
* In two cases neonatal outcome was not reported. Three patients died before
delivery and 23 died after delivery.
CI, confi dence interval; CVP, central venous pressure; PAP, pulmonary artery
pressure; SAP, systemic arterial pressure.
(From Weiss BM, Zemp L, Burkhardt S, Hess O. Outcome of pulmonary vascular
disease in pregnancy: a systemic overview from 1978 through 1996. J Am Coll
Cardio 1998;31:1650 – 1657.)
Cardiac Disease
263
functional right ventricle beyond the apically displaced tricuspid
valve provides effective forward pulmonary blood fl ow. However,
at times the functional right ventricle may be extremely small and

barely able to produce enough forward pulmonary fl ow to sustain
adequate blood pressure. Those women who reach childbearing
years may have either the acyanotic or cyanotic form of Ebstein ’ s
anomaly. Since pulmonary hypertension is not seen in this
anomaly, as noted, the cyanosis is determined by the degree of
right to left shunting across the patent foramen ovale from tri-
cuspid regurgitation. Fetal prematurity, loss and low birth weight
are more common in the cynanotic form of Ebstein ’ s anomaly,
refl ecting this fi nding. It is extremely unusual for the non -
cyanotic form of Ebstein ’ s anomaly to convert to a cyanotic form
once patients have reached maturity. However, this is dependent
upon the degree of tricuspid regurgitation and the functional
capacity of the non - atrialized portion of the right ventricle.
Therefore, evaluation of oxygen and volume status is an impor-
tant consideration during gestation, labor and delivery.
Paroxysmal atrial arrhythmias have been reported to occur in
up to one - third of non - pregnant women with Ebstein ’ s anomaly
and represent a potential concern during pregnancy. The Wolff –
Parkinson – White syndrome is an arrhythymia classically associ-
ated with Ebstein ’ s anomaly and may represent a risk factor for
excessively rapid ventricular rates in response to the increased
incidence of atrial arrhythmias that are associated with Ebstein ’ s
anomaly [56] .
Despite these concerns, in a review of 111 pregnancies in 44
women, no serious maternal complications were noted. Seventy -
six per cent of pregnancies ended in live births, with a 6% inci-
dence of congenital heart disease in the offspring of these women
[55] .
Coarctation of the a orta
Coarctation of the aorta accounts for approximately 10% of all

congenital cardiac disease. The most common site of coarctation
is usually at the origin of the left subclavian artery. Associated
anomalies of the aorta and left heart, including VSD and PDA,
are common, as are intracranial aneurysms in the circle of Willis
[57] . Coarctation is often asymptomatic. Its presence is suggested
by hypertension confi ned to the upper extremities, although
Goodwin [58] cites data suggesting a generalized increase in
peripheral resistance throughout the body. Resting cardiac output
may be increased; however, increased left atrial pressure with
exercise suggests occult left ventricular dysfunction. Aneurysms
also may develop below the coarctation or involve the intercostal
arteries and may lead to rupture. In addition, ruptures without
prior aneurysm formation have been reported [59] .
Over 150 patients with uncorrected and corrected coarctation
of the aorta have been reported during pregnancy, with maternal
mortality ranging from 0% to 17% [25,59,60] . In a 1940 review
of 200 pregnant women with coarctation of the aorta, Mendelson
[61] reported 14 maternal deaths and recommended routine
abortion and sterilization for these patients. Deaths in this series
were from aortic dissection and rupture, congestive heart failure,
branch can be quite diffi cult in the presence of markedly elevated
pulmonary pressures. These patients require ICU monitoring,
and are increased risk of pulmonary artery rupture, pulmonary
infarction, and dysrhythmia. They also require suspension of any
oral anticoagulation before placement,with increased risk of pul-
monary artery thrombosis. Many now believe the risk of this
technique far outweighs the its benefi ts in patients with cyanotic
heart disease [48] and its use is rare. In many cases, pulse oxim-
etry may offer appropriate guidance in the intrapartum manage-
ment of these patients without the need for and/or the associated

risks of, pulmonary artery catheterization. Because the primary
concern in such patients is the avoidance of hypotension, any
attempt at preload reduction (i.e. diuresis) must be undertaken
with great caution, even in the face of initial fl uid overload. We
prefer to manage such patients on the “ wet ” side, maintaining a
preload margin of safety against unexpected blood loss, even at
the expense of mild pulmonary edema. Recently, the use of
inhaled nitric oxide and intravenous prostacyclin therapy have
shown promise as potentially helpful agents in reducing the pul-
monary vascular resistance while relatively sparing the systemic
vascular resistance [49,50] .
Anesthesia for patients with pulmonary hypertension is con-
troversial. Theoretically, conduction anesthesia, with its accom-
panying risk of hypotension, should be avoided. However, there
are several reports of its successful use in patients with pulmonary
hypertension of different etiologies [51,52] . The use of epidural
or intrathecal morphine sulfate, a technique devoid of effect on
systemic BP, represents perhaps the best approach to anesthetic
management of these diffi cult patients.
Although the AHA recommendations for antibiotic prophy-
laxis to prevent endocarditis have been extensively revised, the
recommendations regarding cyanotic congenital heart disease
have not. Endocarditis prophylaxis continues to be recommended
for cyanotic congenital heart disease [28] .
Ebstein ’ s a nomaly
Because it accounts for less than 1% of all congenital cardiac
disease, Ebstein ’ s anomaly is uncommonly encountered during
pregnancy [53 – 55] . This anomaly consists of apical displacement
of the tricuspid valve into the right ventricle, sometimes markedly
so, with secondary tricuspid regurgitation of varying degrees, and

enlargement of the right atrium by incorporation of the right
ventricle situated above the tricuspid valve (the so called “ atrial-
ized right ventricle ” ). A patent foramen ovale may be present in
the interatrial septum and thus these patients may have non -
cyanotic or cyanotic form of the anomaly. The presence or
absence of cyanosis and hemodynamic consequences of Ebstein
anomaly result from the degree of displacement of the tricuspid
valve leafl ets and extent of atrialization of the right ventricle. The
severity of tricuspid regurgitation and hence shunting across the
patent foramen ovale depends on the extent of leafl et displace-
ment, ranging from mild regurgitation with minimal displace-
ment to severe tricuspid regurgitation with more apical
displacement and atrialization of the right ventricle. Usually the
Chapter 20
264
unproven, to decrease the force of left ventricular ejection into
the aorta and to reduce aortic wall stress. Despite these concerns,
most patients with a successfully repaired coarctation of the aorta
have a relatively unremarkable pregnancy. Saidi, et al [63] fol-
lowed 18 pregnancies in women who had undergone a successful
repair of their aortic coarctations. All 18 women had uneventful
pregnancies. Interestingly, the incidence of pre - eclampsia in this
series was no different than that reported in the normal popula-
tion. Maternal risk, however, is clearly increased if pre - eclampsia
develops [66] . In a recent retrospective study of 100 women [65] ,
a higher incidence of hypertension and pre - eclampsia was
found in women who had previously had a repair of coarctation
of the aorta. Interestingly, 80% had had end - to - end surgical
resection at a median age of 6 years, 13% had required interven-
tion for recoarctation and 30% were noted to have hypertension

at the time of the review. This supports the contention that chil-
dren often outgrow their initial surgery and that hypertension is
quite common even after successful repair of coarctation of the
aorta.
In the presence of aortic or intervertebral aneurysm, known as
aneurysm of the circle of Willis, or associated cardiac lesions, the
risk of death may approach 15%; therefore, termination of preg-
nancy should be strongly considered.
Tetralogy of Fallot
Tetralogy of Fallot refers to four key anatomic features which lead
to cyanosis: VSD, overriding aorta, right ventricular hypertrophy,
and pulmonary stenosis. In the United States, most cases of tetral-
ogy of Fallot are corrected during infancy or childhood. Most of
the women with this condition at childbearing age have had it
surgically corrected but many have residual lesions such as
ongoing VSD through a VSD patch, pulmonary insuffi ciency of
varying degrees with right heart enlargement, prosthetic pulmo-
nary valve, residual right ventricular outfl ow tract obstruction, or
a combination of these. A few will have only had palliative pro-
cedures and are cyanotic [67] . Rarely do they present in the
cyanotic state without any prior surgical correction.
Several published reports attest to the relatively successful
outcome of pregnancy in patients with totally or partially cor-
rected tetralogy of Fallot [66,68] . For the totally corrected patient,
pregnancy outcome is similar to that of the general population.
For those with residual lesions including mild pulmonic and/or
tricuspid regurgitation, mild pulmonary stenosis, or small VSD
patch leak, the maternal and fetal risk is minimal. If there is sig-
nifi cant right heart enlargement from residual pulmonary insuf-
fi ciency, right ventricular outfl ow obstruction or pulmonic

stenosis, the risk is higher for development of arrhythmias or
heart failure during pregnancy. However, these patients still can
be managed successfully if they fi rst present during pregnancy.
Women with uncorrected tetralogy of Fallot do not fare as well.
In a review of 55 pregnancies in 46 patients, there were no mater-
nal deaths among nine patients with correction of this lesion
before pregnancy; in patients with an uncorrected lesion, however,
maternal mortality has traditionally ranged from 4% to 15%,
cerebral vascular accidents, and bacterial endocarditis. Six of the
14 deaths occurred in women with associated lesions. In contrast
to this dismal prognosis, a more recent series by Deal and Wooley
[60] reported 83 pregnancies in 23 women with uncomplicated
coarctation of the aorta. All were NYHA class I or II before preg-
nancy. In these women, there were no maternal deaths or perma-
nent cardiovascular complications. In one review, aortic rupture
was more likely to occur in the third trimester, before labor and
delivery [62] . More recent reviews have also supported the fi nding
that improved surgical and percutaneous techniques, medical
therapy for hypertension, and improvement in the management
of these women during pregnancy have resulted in more favor-
able maternal outcomes [63 – 65] .
Thus, it appears that today, patients with coarctation of the
aorta uncomplicated by aneurysmal dilation or hemodynamically
signifi cant associated cardiac lesions who enter pregnancy as class
I or II have a good prognosis and a minimal risk of complications
or death. Even if uncorrected, uncomplicated coarctation has
historically carried with it a risk of maternal mortality of only
3 – 4% [58] . These unrepaired patients should be considered for
repair of their coarctation after the postpartum period is con-
cluded and before contemplation of a next pregnancy. Those

pregnant women who have uncontrolled symptomatic hyperten-
sion attributable to coarctation despite maximal medical therapy
should have a stent placed at the coarctation site. This procedure
is 90% successful with < 20 mmHg residual gradient. The risk of
fetal irradiation is low compared to the high maternal risk of
death from heart failure, arrhythmia, dissection, stroke, and myo-
cardial infarction. The fetal risk can further be reduced by involv-
ing a radiation physicist from the hospital who can help calculate
the radiation dose based on the distance of the X - ray tube from
the mother ’ s abdomen, by shielding the mother ’ s abdomen with
lead (both anterior and posterior), and by performing the proce-
dure after the second trimester. Surgical intervention for coarcta-
tion of the aorta in a pregnant woman is not ideal.
For those with previously surgically repaired coarctation of the
aorta, the maternal outcome appears good [63,65] . Surgical
repair of the coarctation, often accomplished in early childhood,
usually results in long - term normalization of blood pressure.
However, those who have surgeries done at an early age require
ongoing surveillance since the site of surgical intervention does
not typically “ grow ” with the child and further intervention may
be necessary for redevelopment of hypertension, aneurysm at the
site of the surgical repair, or other issues related to the repair.
Percutaneous catheter - based interventional techniques for treat-
ment of coarctation are also being widely used as well, for man-
agement of both children and older patients. Weakness in the
aortic wall, both proximal and distal to the repair, is histologically
similar (cystic medial necrosis) to the aortic weakness exhibited
in Marfan syndrome and bicuspid aortic valve. This abnormality
can be amplifi ed during pregnancy. For women who have unre-
paired coarctation of the aorta, who have residual coarctation

after surgical or interventional therapy, or who have a residual
gradient, β - blockade therapy seems reasonable, although
Cardiac Disease
265
For those in whom the diagnosis is established, both maternal
outcome and pregnancy is generally well tolerated with NYHA
class I or II symptoms [70] . It is still diffi cult to quantify RV
function due to the lack of a suitable control group for compari-
son, and because of the dependence on shape assumptions and
loading conditions of the commonly used systolic indices.
Nevertheless, those with severe AV valve regurgitation or severely
depressed morphologic RV function should be counseled against
pregnancy regardless of functional class. Lessons being learned
from those who have had atrial switch operations for D - TGA (see
below) and similar systemic arterial RV functional issues may be
of help in this group of patients.
D - transposition ( D - TGA )
D - transposition or complete transposition of the great vessels is
incompatible with prolonged life after birth. In this condition,
the transposed aorta is connected to the RV and the pulmonary
artery to the LV. The atria and ventricles are not transposed so
that systemic venous return to the RV is ejected into the aorta.
This defect requires urgent surgical palliation and then subse-
quent complete repair. The fi rst complete repair involved the
“ atrial switch ” operation. Both the Mustard and Senning opera-
tions in the late 1950s and early 1960s revolutionized the manage-
ment of babies with D - TGA and became the treatment of choice.
In this operation, the systemic venous fl ow from the RA is redi-
rected into the LV and PA, while the systemic arterial fl ow is
redirected from the pulmonary veins into the morphologic RV

to the aorta. Since the morphologic RV serves as the systemic
arterial ventricle, similar issues arise to those seen with L - TGA,
and the key to long - term outcome is the fate of the RV. In addi-
tion, because of the extensive surgical intervention to the atria in
redirection of fl ow, signifi cant arrhythmias have been described
in both types of surgeries. This procedure has been largely aban-
doned in favor of the arterial switch begun in the 1980s [71]
because of these concerns. This procedure appears to reduce the
late morbidity rates that have been described with the atrial
repairs [72,73] . Women that have had successful arterial switch
procedures are now entering reproductive ages. The arterial
switch procedure is done within days of birth. Both great arteries
are transected and reanastomosed above the sinuses of Valsalva,
and the coronary arteries are translocated. The native pulmonary
valve becomes the systemic outfl ow valve, and the anatomic pul-
monary root is subjected to systemic blood pressure. The native
valves are not touched. Short - and midterm follow - up of these
patients have shown coronary artery narrowing, pulmonary
artery stenosis, neoaortic valve aortic insuffi ciency, and neoaortic
root dilation [74,75]
The risk of pregnancy in patients with D - transposition who
have had the Mustard or Senning procedure is related to the
severity of any heart failure present, the degree of AV valve regur-
gitation, the degree of resultant pulmonary hypertension and the
presence of arrhythmias. A series of pregnant patients who were
followed subsequent to the Mustard (atrial switch) operation
reported 12 of 15 live births and no maternal deaths [76] . In a
with a 30% fetal mortality due to hypoxia [66,69] . In patients
with uncorrected VSD and right ventricular outfl ow tract obstruc-
tion or pulmonic stenosis, the decline in SVR that accompanies

pregnancy can lead to worsening of the right to left shunt. This
condition can be aggravated further by systemic hypotension as
a result of peripartum blood loss. A poor prognosis for successful
pregnancy has been related to several prepregnancy parameters,
including a hemoglobin exceeding 20 g/dL, a history of syncope
or congestive failure, electrocardiographic evidence of right ven-
tricular strain, cardiomegaly, right ventricular pressure in excess
of 120 mmHg, and peripheral oxygen saturation below 85%.
Women who present with a palliative shunt procedure only from
childhood may be cyanotic and/or have pulmonary hypertension
with the same attendant problems as outlined in the section on
pulmonary hypertension/Eisenmenger ’ s syndrome. If they are
found to have this problem they should be discouraged from
attempting or continuing pregnancy.
Transposition of the g reat v essels
Transposition of the great vessels consists of two types:
• L - transposition; the so - called congenitally corrected transposi-
tion of the great arteries
• D - transposition: the complete transposition.
L - transposition ( L - TGA )
In L - transposition, or congenitally corrected transposition, the
great arteries are transposed. This accounts for less than 1% of all
congenital cardiac defects. In this defect, the atria and ventricles
are also transposed. Hence there is a double discordance of the
atrial - ventricular and ventricular - arterial connections. The right
ventricle is attached to the aorta and acts as the systemic arterial
ventricle receiving oxygenated blood from the lungs and left
atrium. The morphologic left ventricle is attached to the pulmo-
nary artery and acts as the systemic venous ventricle receiving
venous blood from the right atrium, IVC and SVC. Although the

morphologic right ventricle is not designed to accommodate sys-
temic arterial pressures, it may accommodate this pressure well
for years. Ventricular dysfunction and AV valve regurgitation are
recognized and important complications of patients with L - TGA
but this may present slowly and insidiously and does not happen
in all L - TGA patients. Although RV dilation is common, few
develop evidence of symptomatic heart failure. Serial studies do
not indicate that there is an inevitable progressive downward and
progressive deterioration of function with time. Heart failure
symptoms are typical, as one would expect, with pulmonary
edema, increasing pulmonary pressures and decreased forward
systemic arterial output. This condition is detected later in life
usually when the morphologic right ventricle can no longer
accommodate systemic arterial pressures or the AV valve becomes
regurgitant and symptoms of shortness of breath, palpitations,
and arrhythmia become manifest. Disconcertingly, the diagnostic
anatomic features of this congenital defect may be missed on
echocardiography by adult cardiologists not trained in congenital
heart disease.
Chapter 20
266
Functional s ingle v entricle and Fontan p rocedure
Some of the anomalies described as a functional single ventricle
that will ultimately undergo staged reconstructive procedures
resulting in a “ Fontan circulation ” are tricuspid atresia, hypoplas-
tic left heart, double - inlet left ventricle, and some variations of
double - outlet right ventricle. Given the variety of lesions and the
infrequency of this procedure, data on pregnancy outcomes after
Fontan operation are limited [82,83] . In the small numbers
reported in the United States, no maternal deaths have occurred.

Pregnancies in these patients have been associated with an
increased incidence of spontaneous abortions, however. In a
small survey from the Netherlands, 10 pregnancies in 6 women
were associated with a 50% miscarriage rate and one aborted
ectopic pregnancy. In the four live births, NYHA class deteriora-
tion, atrial fi brillation and premature delivery were reported.
There were no maternal deaths. Thus, at this early stage, although
maternal death does not appear to be prominent in patients who
have undergone a Fontan repair with their specifi c underlying
congenital lesion and who have elected to proceed with preg-
nancy, there appears to be a substantial risk for spontaneous
abortion, as well as other signifi cant obstetric and cardiac issues.
Fetal c onsiderations
Perinatal outcome in patients with cyanotic congenital cardiac
disease correlates best with hematocrit; successful outcome in
patients with a hematocrit exceeding 65% or hemoglobin exceed-
ing 20 g/dL is unlikely. Presbitero and associates [13] described
outcome in 96 pregnancies complicated by cyanotic congenital
heart disease. Patients with Eisenmenger ’ s syndrome were
excluded from this analysis. Although only one maternal death
was seen (from endocarditis 2 months postpartum), the preg-
nancy loss rate was 51%. Functional class III or IV, hemoglobin
greater than 20 g/dL, and a prepregnancy oxygen saturation less
than 85% all were associated with a high risk for poor pregnancy
outcome. Such patients have an increased risk of spontaneous
abortion, intrauterine growth restriction, and stillbirth. Maternal
P
a
O
2

below 70 mmHg results in decreased fetal oxygen saturation;
thus, P
a
O
2
should be kept above this level during pregnancy,
labor, and delivery. In the presence of maternal cardiovascular
disease, the growth - restricted fetus is especially sensitive to intra-
partum hypoxia, and fetal decompensation may occur more
rapidly [7,84] . During the antepartum period, serial antepartum
sonography for the detection of growth restriction and antepar-
tum fetal heart rate testing are recommended in any patient with
signifi cant cardiac disease. Fetal activity counting also may be of
value in patients with severe disease [85] . In a series of six patients
with cyanotic cardiac disease, every pregnancy was eventually
delivered secondary to fetal, rather than maternal, deterioration
[86] .
Of equal concern in patients with congenital heart disease is
the risk of fetal congenital cardiac anomalies. This risk appears to
be of the order of 5%, although one older study suggested that
similar series of seven patients with transposition having under-
gone the Mustard procedure, no maternal deaths were reported
[77] . In one case, however, pregnancy termination was necessary
due to maternal deterioration. In the largest series described thus
far, using a retrospective nationwide registry in the Netherlands,
outcomes of 70 women with D - transposition and Mustard or
Senning operations were reported [78] . Forty - two were childless
of whom 35 wished to bear children in the future. Of the 28
patients who completed 49 pregnancies, all were in NYHA class
I or II before pregnancy. There was clinical deterioration in

NYHA in one - third of pregnancies and development of clinically
signifi cant arrhythmias in 20% of these pregnancies. No maternal
deaths occurred. The cardiac issues were manageable. However,
there was a high incidence of obstetric complications. The authors
indicated that in contrast to what is generally assumed, pregnancy
is not always well tolerated in these patients. They also estimate
that approximately 4500 women with this congenital lesion and
surgical procedure will enter childbearing age in the USA over
the next few years.
Women who have had the Jatene (arterial switch) procedure
are only now entering their childbearing years. There has been a
case report, cited frequently, of a successful pregnancy and deliv-
ery in a patient with D - transposition and arterial switch [79] .
Pulmonic s tenosis
Pulmonic stenosis is a common congenital defect. Although
obstruction can be valvular, supravalvular, or subvalvular, the
degree of obstruction, rather than its site, is the principal deter-
minant of clinical performance [8] . Maternal well - being is rarely
signifi cantly affected by pulmonic stenosis. Even 30 years ago, a
compilation (totaling 106 pregnancies) of three series of patients
with pulmonic stenosis revealed no maternal deaths [25 – 27] .
With severe stenosis, right heart failure can occur; fortunately,
this is usually less clinically severe than is the left heart failure
associated with mitral or aortic valve lesions. Symptoms of
dyspnea, angina, syncope or presyncope can occur in those with
markedly stentotic lesions. Severe pulmonic stenosis is defi ned by
a peak valvular gradient of more than 80 mmHg. Because this
degree of obstruction imposes a signifi cant load on the right
ventricle, patients with severe pulmonic stenosis usually benefi t
from balloon valvuloplasty even in the absence of symptoms. In

these women with severe pulmonic stenosis, pregnancy may be
associated with increased risk during labor, delivery, and the
puerperium. The fi rst balloon valvuloplast was performed in
1982. Balloon valvuloplasty in pregnancy has since been per-
formed successfully and with relatively low complication rates
[80] . The incidence of fetal congenital heart disease in patients
with pulmonic valve stenosis appears to be approximately 20%,
with a 55% concordance rate [81] .
Aortic s tenosis
Congenital and rheumatic aortic valvular disease are important
causes of aortic stenosis. The impact of aortic stenosis on preg-
nancy will be discussed in Acquired cardiac lesions.
Cardiac Disease
267
and pedal edema mimic the symptoms of valvular heart disease
making the clinical diagnosis diffi cult. Jugular venous distention,
brisk and collapsing pulses, and a diffuse and laterally displaced
left ventricular impulse, all normal physiologic adaptations to
pregnancy, further confound the clinical assessment. On auscul-
tation of the normal heart during pregnancy, it is not unusual to
hear an accentuated fi rst heart sound (S1) or a systolic fl ow
murmur that peaks in midsystole and is best appreciated along
the left sternal border. A third heart sound (S3), a fourth heart
sound (S4), or a diastolic murmur are uncommon in normal
pregnancy and require an echocardiographic assessment.
Doppler echocardiography in normal pregnancy refl ects the
physiologic consequences of the increased intravascular volume
and blood fl ow on the cardiac chambers and valves. There is an
increase in the left ventricular end - diastolic dimension and a
decrease in the left ventricular end - systolic dimension represent-

ing an increase in both the stroke volume and ejection fraction.
The aortic root dimension, as well as the mitral and tricuspid
annuli, are slightly increased. The left ventricular mass increases
by as much as 30% with minimal changes in wall thickness [91] .
Flow velocities across the aortic valve are minimally increased but
rarely exceed 1.5 m/s by Doppler assessment. Campos et al. [92]
studied 18 pregnant women longitudinally throughout preg-
nancy utilizing Doppler echocardiogram. Mild valvular regurgi-
tation was detected consistently throughout pregnancy. Aortic
regurgitation was rarely detected; however, mitral (0 – 28%)
tricuspid (39 – 94%), and pulmonic regurgitation (22 – 94%) were
found to increase substantially from early to late gestation. Table
20.7 reviews the effect of pregnancy on the clinical and echocar-
diographic fi ndings associated with cardiac valvular abnormali-
ties [81] .
Acquired valvular lesions generally are rheumatic in origin,
although endocarditis secondary to intravenous drug abuse may
the actual risk may be as high as 10%, or even higher in women
whose congenital lesion involves ventricular outfl ow obstruction
[13,81,87,88] (see Figure 20.3 ). In such patients, fetal echocar-
diography is indicated for prenatal diagnosis of congenital cardiac
defects [89] . Of special interest is that affected fetuses appear to
be concordant for the maternal lesion in approximately 50% of
cases. The genetics and embryologic development of congenital
cardiac defects have been reviewed by Clark [90] .
Acquired c ardiac l esions
Many common complaints associated with normal pregnancy
including dyspnea, fatigue, orthopnea, palpitations, presyncope
Figure 20.3 Echocardiographic image of a fetus at 19 weeks in a mother with
a ventricular septal defect (VSD). A similar VSD is demonstrated in this fetus.

Table 20.7 The effect of pregnancy on the clinical and echocardiographic fi ndings associated with cardiac valvular abnormalities.
Heart sounds Murmur Other Doppler echocardiography
Aortic stenosis (AS) Diminished or single S2 –
unchanged
Increase in intensity and duration Systolic ejection click unchanged Increase in Doppler gradient;
AVA unchanged
Aortic insuffi ciency (AI) Diminished S2 – unchanged Decreased or unchanged Wide pulse pressure – increased
or unchanged
LV dimensions may increase
secondary to pregnancy not AI
Mitral stenosis (MS) Loud 1 – increased; P2 –
increased
Increased decrease or unchanged S2 – OS interval gradient, decrease
in pressure half - time and
increase in calculated MVA
Increase in Doppler
Mitral regurgitation (MR) Diminished S1 – unchanged Decreased or unchanged S3 – unchanged to pregnancy not
MR
LV dimensions may increase
secondary
Pulmonic stenosis (PS) Diminished P2 – unchanged Increase in intensity and duration Systolic ejection click unchanged Increase in Doppler gradient
Pulmonic insuffi ciency (PI) Diminished P2 – unchanged Decreased or unchanged N/A secondary to pregnancy not
PI
RV dimensions may increase
Tricuspid stenosis (TS) N/A Increased N/A N/A
Tricuspid regurgitation (TR) N/A unchanged Decreased or secondary to
pregnancy not TR
N/A RV dimensions may increase
AVA, arteriovenous anastomosis; LV, left ventricle; MVA, mitral valve anastomosis; RV, right ventricle.
Chapter 20

268
diagnosis of mitral stenosis will be discovered for the fi rst time
during pregnancy, illustrating what is frequently referred to as
“ occult ” mitral stenosis. The hemodynamic changes accompany-
ing normal pregnancy may represent the fi rst time the patient ’ s
cardiovascular system has been signifi cantly stressed. These
patients may present with “ acute ” pulmonary edema and/or atrial
fi brillation as the initial diagnostic clue to the presence of mitral
stenosis. When clinical symptoms persist despite attentive medical
management, interventional therapy may be prudent.
Percutaneous balloon mitral valvuloplasty during pregnancy has
become increasingly prevalent. More than 100 pregnant women
have undergone percutaneous balloon mitral valvuloplasty
without periprocedural maternal or fetal mortality. Multiple case
reports [95 – 97] and case series [98 – 105] support the relative
safety of this procedure during pregnancy. Procedural complica-
tions include cardiac tamponade, maternal arrhythmias, tran-
sient uterine contractions, and systemic thromboembolism.
Transesophageal echocardiography can be used as the sole
imaging modality, thereby eliminating the undesired radiation
exposure associated with fl uoroscopy.
Cardiac output in patients with mitral stenosis is largely depen-
dent on two factors. First, these patients are dependent on ade-
quate diastolic fi lling time. Thus, while in most patients
tachycardia is a clinical sign of underlying hemodynamic instabil-
ity, in patients with mitral stenosis, the tachycardia itself, regard-
less of etiology, may contribute signifi cantly to hemodynamic
decompensation. During labor, such tachycardia may accompany
the exertion of pushing or be secondary to pain or anxiety. Such
a patient may exhibit a rapid and dramatic fall in cardiac output

and BP in response to tachycardia. This fall compromises mater-
nal as well as fetal well - being. To avoid hazardous tachycardia,
the physician should consider intravenous β - blocker therapy for
any patient with severe mitral stenosis who enters labor with a
pulse exceeding 90 – 100 bpm. A short acting β - blocker, such as
esmolol, is ideal in that minute - to - minute heart rate control can
be achieved without the undesired prolonged beat - blockade that
is associated with more conventional agents such as propranolol.
Another consideration is use of intravenous calcium channel
blocking agents such as diltiazem with which the cardiologists
and nursing personnel are generally familiar and for which
administration is easier. In patients who are not initially tachy-
cardic, acute control of tachycardia with an intravenous β -
blocking agent is only rarely necessary [42] .
A second important consideration in patients with mitral ste-
nosis is left ventricular preload. In the presence of mitral stenosis,
pulmonary capillary wedge pressure is not an accurate refl ection
of left ventricular fi lling pressures. Such patients often require
high - normal or elevated pulmonary capillary wedge pressures to
maintain adequate ventricular fi lling pressure and cardiac output.
Any preload manipulation (i.e. diuresis), therefore, must be
undertaken with extreme caution and careful attention to main-
tenance of cardiac output.
Potentially dangerous intrapartum fl uctuations in cardiac
output can be minimized by using epidural anesthesia [106] ;
occasionally occur, especially with right heart lesions. During
pregnancy, maternal morbidity and mortality with such lesions
result from congestive failure with pulmonary edema or arrhyth-
mias. Szekely et al. [93] found the risk of pulmonary edema in
pregnant patients with rheumatic heart disease to increase with

increasing age and with increasing length of gestation. The onset
of atrial fi brillation during pregnancy carries with it a higher risk
of right and left ventricular failure (63%) than does fi brillation
with onset before gestation (22%). In addition, the risk of sys-
temic embolization after the onset of atrial fi brillation during
pregnancy appears to exceed that associated with onset in the
non - pregnant state. In counseling the patient with severe rheu-
matic cardiac disease on the advisability of initiating or continu-
ing pregnancy, the physician must also consider the long - term
prognosis of the underlying disease. Chesley [94] followed 134
women who had functionally severe rheumatic heart disease and
who had completed pregnancy for up to 44 years. He reported a
mortality of 6.3% per year but concluded that in patients who
survived the gestation, maternal life expectancy was not short-
ened by pregnancy. Thus, in general, pregnancy does not appear
to introduce long - term sequelae for patients who survive the
pregnancy [44] .
Pulmonic and t ricuspid l esions
Isolated right - sided valvular lesions of rheumatic origin are
uncommon; however, such lesions are seen with increased fre-
quency in intravenous drug abusers, where they are secondary to
valvular endocarditis. Pregnancy - associated hypervolemia is far
less likely to be symptomatic with right - sided lesions than with
those involving the mitral or aortic valves. In a review of 77
maternal cardiac deaths, Hibbard [27] reported no deaths associ-
ated with isolated right - sided lesions. In a more recent review,
congestive heart failure occurred in only 2.8% of women with
pulmonic stenosis [87] . Even following complete tricuspid val-
vectomy for endocarditis, pregnancy, labor, and delivery are gen-
erally well tolerated. Cautious fl uid administration is the mainstay

of labor and delivery management in such patients. In general,
invasive hemodynamic monitoring during labor and delivery is
not necessary.
Mitral s tenosis
Mitral stenosis is the most common rheumatic valvular lesion
encountered during pregnancy [42] . It can occur as an isolated
lesion or in conjunction with aortic or right - sided lesions. When
mitral stenosis is signifi cant (valve area < 1.0 cm
2
) the principal
hemodynamic aberration involves a left ventricular diastolic
fi lling obstruction, resulting in a relatively fi xed cardiac output.
Marked increases in cardiac output accompany normal preg-
nancy, labor, and delivery. If the pregnant patient is unable to
accommodate such volume fl uctuations, atrial arrhythmias and/
or pulmonary edema may result.
Ideally it is best to treat signifi cant mitral stenosis before preg-
nancy with balloon and/or surgical commissurotomy. Often the