Essential Revision Notes for MRCP, 4E[NewMedicalBooks]

Essential
Revision Notes
for MRCP
Fourth Edition


Dedication
To my wife, Marian, and children, Michael, Gabriella and Alicia, who will always inspire


Essential
Revision Notes
for MRCP
Fourth Edition
edited by
Philip A Kalra MA MB BChir FRCP MD
Consultant and Honorary Professor of Nephrology,
Salford Royal NHS Foundation Trust and The University of Manchester


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First published 1999
Reprinted 1999

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Reprinted 2003
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Reprinted 2009
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Contents
Contributors to Fourth Edition
Contributors to Third Edition
Permissions
Preface to the Fourth Edition
CHAPTER
1.

Cardiology
J E R Davies, S Nijjer

2.

Clinical Pharmacology, Toxicology and
Poisoning
S Waring

3.

Dermatology
H Robertshaw

4.

Endocrinology
T Kearney, S Giritharan, M Kumar

5.

Epidemiology
J Ritchie

6.

Gastroenterology
S Lal, D H Vasant

7.

Genetics
E Burkitt Wright

8.

Genito-urinary Medicine and AIDS
B Goorney

9.

Haematology
K Patterson

10.

Immunology
J Galloway
Infectious Diseases and Tropical Medicine

11.

C L van Halsema

12.

Maternal Medicine
L Byrd

13.

Metabolic Diseases
S Sinha

14.

Molecular Medicine
K Siddals

15.

Nephrology
P Kalra

16.

Neurology
M Jones, C Kobylecki, D Rog

17.

Ophthalmology
K Smyth

18.

Psychiatry
E Sampson

19.

Respiratory Medicine
H Green

20.

Rheumatology
M McMahon

21.

Statistics
E Koutoumanou

Index


Contributors to Fourth Edition

Emma Burkitt Wright MBChB PhD MRCP(UK)
Specialist Registrar and Honorary Clinical Research Fellow, Manchester Centre for Genomic
Medicine, Central Manchester University Hospitals Foundation Trust and University of Manchester,
Chapter 7 Genetics
Louise Byrd MBBS, MRCOG, Dip RCR/RCOG Cert. Medical Education
Consultant in High Risk Obstetrics and Maternal Medicine with special interest in Medical
Education, Central Manchester Foundation Trust, Manchester, Chapter 12 Maternal Medicine
Justin E R Davies BSc, MBBS, PhD, MRCP
Senior Research Fellow and Consultant Cardiologist, Imperial College London, Chapter 1
Cardiology
James Galloway MBChB, MRCP, MSc, PhD, CHP
Clinical Lecturer / Honorary Consultant Rheumatologist, Department of Rheumatology, King’s
College Hospital, London, Chapter 10 Immunology
Sumithra Giritharan MBChB MRCP(UK)
Specialist Registrar, Department of Diabetes and Endocrinology, Salford Royal NHS Foundation
Trust, Manchester, Chapter 4 Endocrinology
Ben Goorney MBChB FRCP
Consultant Genito-Urinary Physician, Department of Genito-Urinary Medicine, Hope Hospital,
Salford, Chapter 8 Genito-Urinary Medicine and AIDS
Heather Green BSc, MBChB (Hons), MRCP(UK), Certificate in Respiratory Medicine
Respiratory Registrar/Research Fellow in Cystic Fibrosis, Manchester Adult Cystic Fibrosis Centre,
University Hospital of South Manchester, Manchester, Chapter 19 Respiratory Medicine
Matthew Jones MD MRCP
Consultant Neurologist and Clinical Teaching Fellow, Department of Neurology, Greater Manchester
Neurosciences Centre, Salford Royal NHS Foundation Trust, Salford, Chapter 16 Neurology
Philip A Kalra MA MB BChir FRCP MD
Consultant and Honorary Professor of Nephrology, Salford Royal NHS Foundation Trust and
University of Manchester, Chapter 15 Nephrology

Eirini Koutoumanou BSc MSc
Senior Teaching Fellow, UCL Institute of Child Health, Population, Policy, Practice Programme,
London, Chapter 21 Statistics
Tara Kearney MB BS, BSc(Hons), FRCP, MD
Consultant Endocrinologist, Salford Royal Foundation NHS Trust, Manchester, Chapter 4
Endocrinology
Mohit Kumar MBChB MRCP
Specialist Trainee, Department of Diabetes, Endocrinology and Weight Management, Salford Royal
Foundation Trust, Salford Manchester, Chapter 4 Endocrinology
Simon Lal BSc MBChB PhD FRCP
Consultant Gastroenterologist, Salford Royal NHS Foundation Trust, Salford, Chapter 6
Gastroenterology
Michael McMahon BSc MBChB FRCP
Consultant Physician and Rheumatologist, Department of Rheumatology, Dumfries and Galloway
Royal Infirmary, Dumfries, Chapter 20 Rheumatology
Sukhjinder S Nijjer BSc (Hons) MBChB (Hons) MRCP(UK)
Cardiology Registrar, Hammersmith Hospital and the International Centre for Circulatory Health,
Imperial College London, Chapter 1 Cardiology
Keith Patterson FRCP FRCPath
Consultant Haematologist, London, Chapter 9 Haematology
James Ritchie MBChB, MRCP PhD
Clinical Research Fellow, Department of Renal Medicine, Salford Royal Hospital, Salford,
Manchester, Chapter 5 Epidemiology
Helen Robertshaw BSc(Hons) MBBS FRCP
Consultant in Dermatology, Royal Bournemouth and Christchurch Hospitals, Bournemouth, Chapter 3
Dermatology
David Rog BMedSci (Hons), BMBS, FRCP, MD
Consultant Neurologist and Honorary Lecturer, Department of Neurology, Greater Manchester
Neurosciences Centre, Salford Royal NHS Foundation Trust, Salford, Chapter 16 Neurology
Liz Sampson MBChB MRCPsych MD MSc

Clinical Senior Lecturer In Old Age Psychiatry, Division of Psychiatry, University College London.
Consultant in Liaison Psychiatry, Barnet Enfield and Haringey Mental Health Trust London, Chapter
18 Psychiatry
Kirk W Siddals BSc PhD
Research Fellow, Vascular Research, Salford Royal Hospital, Manchester, Chapter 14 Molecular


Medicine
Smeeta Sinha MBChB PhD MRCP FRCP
Consultant and Honorary Senior Lecturer in Nephrology, Salford Royal NHS Foundation Trust,
Salford, Chapter 13 Metabolic Diseases
Katherine Smyth MBChB MRCP FRCOpth
Consultant Ophthalmologist, Royal Bolton Hospital, Bolton, Chapter 17 Ophthalmology
Clare L van Halsema MBChB MSc MD MRCP DTM&H Dip HIV Med
Specialist Registrar in Infectious Diseases, Department of Infectious Diseases and Tropical
Medicine, North Manchester General Hospital, Manchester, Chapter 11 Infectious Diseases and
Tropical Medicine
Dipesh H Vasant MB ChB, MRCP(UK)
Clinical Research Fellow and Specialist Registrar in Gastroenterology and Medicine, The University
of Manchester Clinical Sciences Building, Salford Royal NHS Trust, Chapter 6 Gastroenterology
Stephen Waring PhD FRCP (Edin) FRCP FBPharmacolS
Consultant in Acute Medicine & Toxicology, Acute Medical Unit, York Teaching Hospital NHS
Foundation Trust, York, Chapter 2 Clinical Pharmacology, Toxicology and Poisoning


Contributors to Third Edition
Emma Burkitt Wright MBCh MPhil MRCP(UK)
Academic Clinical Fellow, Medical Genetics Research Group and University of Manchester, St
Mary’s Hospital, Manchester Genetics
Louise Byrd MRCOG

Specialist Registrar in Obstetrics and Gynaecology, North West Region Maternal Medicine
Colin M Dayan MA MBBS FRCP PhD
Consultant Senior Lecturer in Medicine, Head of Clinical Research, URCN, Henry Wellcome
Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol Endocrinology
Ben Goorney MBChB FRCP
Consultant Genito-Urinary Physician, Department of Genito-Urinary Medicine, Hope Hospital,
Salford Genito-urinary Medicine and AIDS
Philip A Kalra MA MB BChir FRCP MD
Consultant Nephrologist and Honorary Reader, Hope Hospital, Salford Nephrology
Mike McMahon BSc MBChB FRCP
Consultant Physician and Rheumatologist, Department of Rheumatology, Dumfries and Galloway
Royal Infirmary, Dumfries Immunology & Rheumatology
John Paisey DM MRCP
Consultant Cardiac Electrophysiologist, Royal Bournemouth Hospital, Bournemouth Cardiology
Keith Patterson FRCP FRCPath
Consultant Haematologist, Department of Haematology, University College London Hospitals,
London Haematology
Jaypal Ramesh MRCP(UK)
Consultant Gastroenterologist, University Hospital of South Manchester, NHS Foundation Trust,
Manchester Gastroenterology
Geraint Rees BA BMBCh MRCP PhD
Wellcome Senior Clinical Fellow, Institute of Cognitive Neuroscience, University College London
Neurology
Helen Robertshaw BSc(Hons) MBBS MRCP


Specialist Registrar in Dermatology, Southampton University Hospitals Trust, Southampton
Dermatology
Liz Sampson MBChB MRCPsych MD
Lecturer in Old Age Psychiatry, Royal Free and University College Medical School, University

College London Psychiatry
Kirk W Siddals BSc PhD
Research Fellow, Vascular Research, Salford Royal Hospital, Stott Lane, Salford Molecular
Medicine
Smeeta Sinha MBChB MRCP
Specialist Registrar Nephrology, Salford Royal NHS Foundation Trust, Salford, Manchester
Metabolic Diseases
Katherine Smyth MBChB MRCP FRCOpth
Consultant Opthalmologist, Royal Bolton Hosptial, Bolton Ophthalmology
Clare L van Halsema MBChB MRCP DTM&H
Specialist Registrar in Infectious Diseases, Monsall Unit, Department of Infectious Diseases and
Tropical Medicine, North Manchester General Hospital, Manchester Infectious Diseases
Angie Wade MSc PhD CStat ILTM
Senior Lecturer in Medical Statistics, Institute of Child Health and Great Ormond Street Hospital,
London Statistics
Deborah A Wales MBChB MRCP FRCA
Consultant Respiratory Physician, Nevill Hall Hospital, Brecon Road, Abergavenny, Monmouthshire
Respiratory Medicine
GaryWhitlock BHB MBChB MPH(Hons) PhDFAFPHM
Clinical Research Fellow, Clinical Trial Service Unit, University of Oxford Epidemiology
Stephen Waring MRCP(UK)
Consultant Physician in Acute Medicine and Toxicology, The Royal Infirmary of Edinburgh Clinical
Pharmacology


Permissions
The following have been reproduced with kind permission from BMJ Publishing Group Ltd.
Cardiology
Fig 1.5 – Radionuclide myocardial perfusion imaging. Left panel shows the gamma camera. Right
panel shows a reversible inferolateral perfusion defect: left column stress, right column rest.

Fig 1.6 – Mechanism for atrioventricular nodal re-entry tachycardia
Fig 1.7 – Mechanism for atrioventricular re-entry tachycardia
Maternal Medicine
Table 12.4 – Specific renal diseases and pregnancy
Neurology
Figure 16.2 – Demonstrating how the ‘shape’ of three common neurological conditions – seizures,
transient ischaemic attacks and migraine – and their positive and negative neurological features in the
history help to differentiate them.
The following images in this book have been reproduced with kind permission from Science Photo
Library.
Immunology
Fig 10.3 – Angioedema on the tongue


Preface to the Fourth Edition
I am delighted that ‘Essential Revision Notes for MRCP’ has retained it’s place as one of the key texts
for preparation for the MRCP over a period now extending beyond 15 years. In this latest edition
there has been a significant revision of the text in all of the chapters by experts in the subject, and the
material has been brought right up to date with coverage of the latest clinical developments in the
subject areas.
We continue to use the same successful style of layout within the Essential Revision Notes (ERN)
with emphasis upon ‘user-friendliness’ with succinct text, bullet points and tables. The doublecolumn format enhances readability and revision. The aim is to provide the practising physician with
accessible, concise and up-to-date core knowledge across all of the subspecialties of medicine. For
candidates who are preparing for the MRCP, it fills a unique gap between large detailed textbooks of
medicine and those smaller texts which concentrate specifically on how to pass the examinations.
However, many physicians use the ERN as a career-long companion to be used as a concise source of
reference long after they have successfully collected their exam certificates.
A special thanks goes to our skilled team of contributing authors for their outstanding efforts which
have ensured that this new edition maintains the standard set by previous editions. I am also
particularly grateful to Cathy Dickens, who has been a key contributor to the ERN effort since it’s

initiation in 1998, and to Brad Fallon, for co-ordinating the book production process at PasTest.
Philip A Kalra
Consultant and Honorary Professor of Nephrology
Salford Royal NHS Foundation Trust and University of Manchester


Chapter 1
Cardiology
CONTENTS
1.1 Introduction
1.2 Clinical examination
1.2.1 Jugular venous pressure
1.2.2 Arterial pulse associations
1.2.3 Cardiac apex
1.2.4 Heart sounds
1.3 Cardiac investigations
1.3.1 Electrocardiography
1.3.2 Echocardiography
1.3.3 Nuclear cardiology: myocardial perfusion imaging
1.3.4 Cardiac catheterisation
1.3.5 Exercise stress testing
1.3.6 24-hour ambulatory blood pressure monitoring
1.3.7 Computed tomography
1.3.8 Magnetic resonance imaging
1.4 Valvular disease and endocarditis
1.4.1 Murmurs
1.4.2 Mitral stenosis
1.4.3 Mitral regurgitation
1.4.4 Aortic regurgitation
1.4.5 Aortic stenosis

1.4.6 Tricuspid regurgitation
1.4.7 Prosthetic valves
1.4.8 Infective endocarditis
1.5 Congenital heart disease
1.5.1 Atrial septal defect
1.5.2 Ventricular septal defect


1.5.3
1.5.4
1.5.5
1.5.6
1.5.7

Patent ductus arteriosus
Coarctation of the aorta
Eisenmenger syndrome
Tetralogy of Fallot
Important post-surgical circulations

1.6 Arrhythmias and pacing
1.6.1 Bradyarrhythmias
1.6.2 Supraventricular tachycardias
1.6.3 Atrial arrhythmias
1.6.4 Ventricular arrhythmias and channelopathies
1.6.5 Pacing and ablation procedures
1.7 Ischaemic heart disease
1.7.1 Angina
1.7.2 Myocardial infarction
1.7.3 PPCI for STEMI

1.7.4 Coronary artery interventional procedures
1.8 Heart failure and myocardial diseases
1.8.1 Cardiac failure
1.8.2 Hypertrophic cardiomyopathy
1.8.3 Dilated cardiomyopathy
1.8.4 Restrictive cardiomyopathy
1.8.5 Myocarditis
1.8.6 Cardiac tumours
1.8.7 Alcohol and the heart
1.8.8 Cardiac transplantation
1.9 Pericardial disease
1.9.1 Constrictive pericarditis
1.9.2 Pericardial effusion
1.9.3 Cardiac tamponade
1.10 Disorders of major vessels
1.10.1 Pulmonary hypertension
1.10.2 Venous thrombosis and pulmonary embolism
1.10.3 Systemic hypertension
1.10.4 Aortic dissection
Appendix I
Normal cardiac physiological values


Appendix II
Summary of further trials in cardiology


Cardiology
1.1 INTRODUCTION
Patients with cardiovascular disease form a large part of clinical work and accordingly have

prominence in the MRCP examination. Ischaemic heart disease, valvular disease and arrhythmic
disorders have the largest preponderance of questions. Many of the conditions have overlapping
causes and cardiac pathophysiology is such that one condition can lead to another. Understanding the
pathophysiology will allow clinicians to unpick diagnoses, understand the diseases and answer
examination questions more effectively.

1.2 CLINICAL EXAMINATION
1.2.1 Jugular venous pressure
This is an essential clinical sign that reflects patient filling status and is essential to detect for correct
fluid management. The jugular venous pressure (JVP) reflects right atrial pressure, and in healthy
individuals at 45° is 3 cm in vertical height above the sternal angle (the angle of Louis, the
manubriosternal junction). Inspiration generates negative intrathoracic pressure and a suction of
venous blood towards the heart, causing the JVP to fall (Figure 1.1).
Figure 1.1 The location and wave-form of the jugular venous pressure (JVP). The JVP must be assessed with the patient at 45°


Normal waves in the JVP
The a wave
Due to atrial contraction – actively push up superior vena cava (SVC) and into the right ventricle
(may cause an audible S4).
The c wave
An invisible flicker in the x descent due to closure of the tricuspid valve, before the start of
ventricular systole.
The x descent
Downward movement of the heart causes atrial stretch and a drop in pressure.
The v wave
Due to passive filling of blood into the atrium against a closed tricuspid valve.
The y descent
Opening of the tricuspid valve with passive movement of blood from the right atrium to the right
ventricle (causing an S3 when audible).

Causes of a raised JVP
1.

Raised JVP with normal waveform:
•
Heart failure – biventricular or isolated right heart failure
•
Fluid overload of any cause
•
Severe bradycardia.
Raised JVP upon inspiration and drops with expiration: Kussmaul’s sign is the opposite of
what occurs in health and implies that the right heart chambers cannot increase in size to


2.

3.

accommodate increased venous return. This can be due to pericardial disease (constriction) or
fluid in the pericardial space (pericardial effusion and cardiac tamponade).
Raised JVP with loss of normal pulsations: SVC syndrome is obstruction caused by
mediastinal malignancy, such as bronchogenic malignancy, which causes head, neck and/or arm
swelling.

Pathological waves in the JVP
This is a common source of MRCP Part 1 questions. See Table 1.1 and Figure 1.2 for these waves.
Table 1.1 Pathological waves in the jugular venous pressure (JVP)
a
Absent Atrial fibrillation – no co-ordinated contraction
waves

Large Tricuspid stenosis, right heart failure, pulmonary hypertension
Caused by atrioventricular dissociation – allowing the atria and ventricles to
Cannon
contract at same time:
Atrial flutter and atrial tachycardias
Third-degree (‘complete’) heart block
Ventricular tachycardia and ventricular ectopics
v
Giant
waves

Tricuspid regurgitation – technically a giant ‘c-V’ wave

x
Steep
descent

Tamponade and cardiac constriction
If steep x descent only, then tamponade

y
Steep
descent
Slow

Cardiac constriction
Tricuspid stenosis

Figure 1.2 Different JVP morphologies can reflect different disease states

1.2.2

Arterial pulse associations

The radial arterial pulse is suitable for assessing the rate and rhythm, and whether it is collapsing.
The central arterial pulses, preferably the carotid, are used to assess the character.
Absent radial pulse
•
•
•
•
•
•

Iatrogenic: post-catheterisation or arterial line
Blalock–Taussig shunt for congenital heart disease, eg tetralogy of Fallot
Aortic dissection with subclavian involvement
Trauma
Takayasu’s arteritis
Peripheral arterial embolus.

Pathological pulse characters
•
•
•
•
•

Collapsing: aortic regurgitation, arteriovenous fistula, patent ductus arteriosus (PDA) or other

large extracardiac shunt
Slow rising: aortic stenosis (delayed percussion wave)
Bisferiens: a double shudder due to mixed aortic valve disease with significant regurgitation
(tidal wave second impulse)
Jerky: hypertrophic obstructive cardiomyopathy
Alternans: occurs in severe left ventricular dysfunction. The ejection fraction is reduced
meaning the end-diastolic volume is elevated. This may sufficiently stretch the myocytes
(Frank–Starling physiology) to improve the the ejection fraction of the next heart beat. This
leads to pulses that alternate from weak to strong
Paradoxical (pulsus paradoxus): an excessive reduction in the pulse with inspiration (drop in


•

systolic BP >10 mmHg) occurs with left ventricular compression, tamponade, constrictive
pericarditis or severe asthma as venous return is compromised.

1.2.3

Cardiac apex

The cardiac apex pulsation reflects the ventricle striking the chest wall during isovolumetric
contractions, and gives an indication of the position of the left ventricle and it size. It is typically
palpable in the fifth intercostal space in the midclavicular line.
Absent apical impulse
•
•
•
•

Obesity/emphysema
Right pneumonectomy with displacement
Pericardial effusion or constriction
Dextrocardia (palpable on right side of chest)

Pathological apical impulse
•
•
•
•
•
•
•
•

Heaving: left ventricular hypertrophy (LVH) (and all its causes), sometimes associated with
palpable fourth heart sound
Thrusting/hyperdynamic: high left ventricular volume (eg in mitral regurgitation, aortic
regurgitation, PDA, ventricular septal defect)
Tapping: palpable first heart sound in mitral stenosis
Displaced and diffuse/dyskinetic: left ventricular impairment and dilatation (eg dilated
cardiomyopathy, myocardial infarction [MI])
Double impulse: with dyskinesia is due to left ventricular aneurysm; without dyskinesia in
hypertrophic cardiomyopathy (HCM)
Pericardial knock: constrictive pericarditis
Parasternal heave: due to right ventricular hypertrophy (eg atrial septal defect [ASD],
pulmonary hypertension, chronic obstructive pulmonary disease [COPD], pulmonary stenosis)
Palpable third heart sound: due to heart failure and severe mitral regurgitation.

1.2.4

Heart sounds

Abnormalities of first heart sounds are given in Table 1.2 and of second heart sounds in Table 1.3.
Third heart sound (S3)
Due to the passive filling of the ventricles on opening of the atrioventricular (AV) valves, audible in
normal children and young adults. Pathological in cases of rapid left ventricular filling (eg mitral
regurgitation, ventricular septal defect [VSD], congestive cardiac failure and constrictive
pericarditis).
Table 1.2 Abnormalities of the first heart sound (S1): closure of mitral and tricuspid valves


Loud

Soft

Split

Mobile mitral
stenosis

Immobile mitral
stenosis

RBBB

Hyperdynamic
states

Hypodynamic

states

LBBB

Mitral
regurgitation
Poor ventricular
Left-to-right shunts
function
Short PR interval Long PR interval
Tachycardic states

Vari
able
Atrial
fibrilla
tion
Compl
ete heart
block

VT
Inspiration
Ebstein’s anomaly

LBBB, left bundle-branch block; RBBB, right bundle-branch block; VT, ventricular tachycardia.
Table 1.3 Abnormalities of the second heart sound (S2): closure of aortic then pulmonary valves
(<0.05 s apart)
Intensity

Loud:
Systemic hypertension (loud
A2)
Pulmonary hypertension (loud
P2)
Tachycardic states
ASD (loud P2)
Soft or absent:
Severe aortic stenosis

Splitting

Fixed:
ASD
Widely split:
RBBB
Pulmonary stenosis
Deep inspiration
Mitral regurgitation

Single S2:
Severe pulmonary stenosis/aortic
stenosis
Hypertension
Large VSD
Tetralogy of Fallot
Eisenmenger’s syndrome
Pulmonary atresia
Elderly
Reversed split S2:

LBBB
Right ventricular pacing
PDA
Aortic stenosis

A2, aortic second sound; ASD, atrial septal defect; LBBB, left bundle-branch block; P2, pulmonary
second sound; PDA, patent ductus arteriosus; RBBB, right bundle-branch block; VSD, ventricular
septal defect.
Fourth heart sound (S4)
Due to the atrial contraction that fills a stiff left ventricle, such as in LVH, amyloid, HCM and left


ventricular ischaemia. It is absent in atrial fibrillation.
Causes of valvular clicks
•
•
•

Aortic ejection: aortic stenosis, bicuspid aortic valve
Pulmonary ejection: pulmonary stenosis
Mid-systolic: mitral valve prolapse.

Opening snap
In mitral stenosis an opening snap (OS) can be present and occurs after S2 in early diastole. The
closer it is to S2 the greater the severity of mitral stenosis. It is absent when the mitral cusps become
immobile due to calcification, as in very severe mitral stenosis.

1.3 CARDIAC INVESTIGATIONS
1.3.1 Electrocardiography
Both the axis and sizes of QRS vectors give important information. Axes are defined as:

•
•
•
•

−30° to +90°: normal
−30° to −90°: left axis
+90° to +180°: right axis
−90° to −180°: indeterminate.

Tip: if the QRS is positive in leads 1 and aVF the axis is normal.
The causes of common abnormalities are given in the box below. Electrocardiography (ECG) strips
illustrating typical changes in common disease states are shown in Figure 1.3.
Causes of common abnormalities in the ECG
•

•

Causes of left axis deviation
• Left bundle-branch block (LBBB)
• Left anterior hemi-block (LAHB)
• LVH
• Primum ASD
• Cardiomyopathies
• Tricuspid atresia
Low-voltage ECG
• Pulmonary emphysema
• Pericardial effusion
• Myxoedema

• Severe obesity
• Incorrect calibration
• Cardiomyopathies
• Global ischaemia
• Amyloid
Causes of right axis deviation
• Infancy
• Right bundle-branch block (RBBB)
Right ventricular hypertrophy (eg lung disease, pulmonary embolism, large secundum ASD,
•
severe pulmonary stenosis, tetralogy of Fallot)
Abnormalities of ECGs in athletes
• Sinus arrhythmia
• Sinus bradycardia
• First-degree heart block
• Wenckebach’s phenomenon
• Junctional rhythm

•

•

Clinical diagnoses that can be made from the ECG of an asymptomatic patient
•
•
•
•
•
•

•

Atrial fibrillation
Complete heart block
HCM
ASDs (with RBBB)
Long QT and Brugada’s syndromes
Wolff–Parkinson–White (WPW) syndrome (δ waves)
Arrhythmogenic right ventricular dysplasia (cardiomyopathy).

Short PR interval
This is rarely <0.12 s; the most common causes are those of pre-excitation involving accessory
pathways or of tracts bypassing the slow region of the AV node; there are other causes.
•

•

Pre-excitation
• WPW syndrome
• Lown–Ganong–Levine syndrome (short PR syndrome)
Other
• Ventricular extrasystole falling after P wave
• AV junctional rhythm (but P wave will usually be negative)
• Low atrial rhythm
• Coronary sinus escape rhythm