CARDIOLOGY NOTES
CARDIOVASCULAR EXAM
The second heart sound comprises of aortic (A2) and pulmonary (P2) component. In
LBBB, the aortic closure is delayed because the left ventricle contracts later. This
then causes reversed splitting (A2P2 → P2A2) if the second heart sound.
LBBB and left heart strain in HCM and aortic stenosis can cause reversal of A2P2
second heart sounds. Also, in type B wolf parkinson white syndrome, early activation
of the right ventricle through an accessory pathway can cause P2 to close prematurely.
Patent ductus arteriosus is another cause.
The third heart sound is caused by early diastolic filling due to ventricular
relaxation, shortly after closure of the aortic valve (corresponds to Y descent in JVP).
It may be normal in children and young /middle aged adults.
Causes of an abnormal third heart sound are:
Left ventricular failure
Severe MR and TR
VSD, PDA
Constrictive pericarditis
Hypertrophic cardiomyopathy
Dilated cardiomyopathy
AV fistula
thyrotoxicosis
Causes of an abnormal fourth heart sound are:
Causes of raised JVP are:
Congestive cardiac failure
SVC obstruction
Constrictive pericarditis
Anaemia
Tricuspid regurgitation
Pulsus paradoxus is defined as an inspiratory systolic fall in arterial pressure of
10mmHg. It not only occurs in cardiac tamponade, but also in massive PE, severe
COPD and hypotension/shock.
Cannon a waves occur when the atria and ventricles contract at the same time. The
causes are complete AV block, ventricular tachycardia and AV nodal reentry
tachycardia
CARDIAC ANATOMY
The left internal mammary artery supplies the anterior chest wall. It has been
shown to be superior to saphenous vein grafts (from aorta to LAD) in staying patent
and hence is now the choice artery (LIMA to LAD) graft. Although circumflex and
right coronary arteries are usually grafted with veins, the right internal mammary
arteries (RIMA) are sometimes used to graft the RCA.
MRCPASS NOTES 1
, The circumflex artery gives off obtuse marginal branches and the LAD gives off
diagonal branches.
The intermediate artery is not always present, it is a variant artery which is between
the LAD and circumflex artery, and occasionally dominant instead of the circumflex.
The coronary sinus predominantly drains venous blood from the left ventricle and
receives approximately 85 percent of coronary venous blood. It receives blood from
the the marginal, posterior left ventricular, anterior interventricular veins and the great
cardiac vein. The blood finally drains into the right atrium.
The posterior descending artery is often (85%) a branch of the right coronary artery.
The sinus node artery is a branch of the right coronary artery in 60% of cases.
The AV node is supplied by the posterior descending coronary artery.
ARRHYTHMIAS
Atrial flutter most commonly presents with 2:1 block, which means atrial rate of 300
but ventricular rate of 150. Ischaemic chest pain may occur due to the tachycardia.
Carotid sinus massage can sometimes terminate or slow the tachycardia.
DC cardioversion should be performed if the patient is cardivascularly unstable.
Atrial flutter is commoner in patients with dilated left atrium or in
congenital/structural heart disease.
Differentiating SVT from VT
Features that favour VT are :
QRS of > 140ms,
cannon a waves on JVP
fusion and/or capture beats
dissociated p waves,
history of ischaemic heart disease,
right bundle branch block with left axis deviation,
concordance of the QRS complexes in the chest leads
HR >170 beats per minute.
In a patient who is stable with sustained ventricular tachycardia, the options are
intravenous lignocaine, intravenous amiodarone. IV magnesium sulphate (
mmols or 5g) is often helpful in helping to cardiovert. If the patient were unstable
then he needs to be DC cardioverted immediately (with or without general
anaesthetic).
The criteria for ICD insertion are:
1) patients with LVEF <40% with non sustained VT
MRCPASS NOTES 2
CARDIOVASCULAR EXAM
The second heart sound comprises of aortic (A2) and pulmonary (P2) component. In
LBBB, the aortic closure is delayed because the left ventricle contracts later. This
then causes reversed splitting (A2P2 → P2A2) if the second heart sound.
LBBB and left heart strain in HCM and aortic stenosis can cause reversal of A2P2
second heart sounds. Also, in type B wolf parkinson white syndrome, early activation
of the right ventricle through an accessory pathway can cause P2 to close prematurely.
Patent ductus arteriosus is another cause.
The third heart sound is caused by early diastolic filling due to ventricular
relaxation, shortly after closure of the aortic valve (corresponds to Y descent in JVP).
It may be normal in children and young /middle aged adults.
Causes of an abnormal third heart sound are:
Left ventricular failure
Severe MR and TR
VSD, PDA
Constrictive pericarditis
Hypertrophic cardiomyopathy
Dilated cardiomyopathy
AV fistula
thyrotoxicosis
Causes of an abnormal fourth heart sound are:
Causes of raised JVP are:
Congestive cardiac failure
SVC obstruction
Constrictive pericarditis
Anaemia
Tricuspid regurgitation
Pulsus paradoxus is defined as an inspiratory systolic fall in arterial pressure of
10mmHg. It not only occurs in cardiac tamponade, but also in massive PE, severe
COPD and hypotension/shock.
Cannon a waves occur when the atria and ventricles contract at the same time. The
causes are complete AV block, ventricular tachycardia and AV nodal reentry
tachycardia
CARDIAC ANATOMY
The left internal mammary artery supplies the anterior chest wall. It has been
shown to be superior to saphenous vein grafts (from aorta to LAD) in staying patent
and hence is now the choice artery (LIMA to LAD) graft. Although circumflex and
right coronary arteries are usually grafted with veins, the right internal mammary
arteries (RIMA) are sometimes used to graft the RCA.
MRCPASS NOTES 1
, The circumflex artery gives off obtuse marginal branches and the LAD gives off
diagonal branches.
The intermediate artery is not always present, it is a variant artery which is between
the LAD and circumflex artery, and occasionally dominant instead of the circumflex.
The coronary sinus predominantly drains venous blood from the left ventricle and
receives approximately 85 percent of coronary venous blood. It receives blood from
the the marginal, posterior left ventricular, anterior interventricular veins and the great
cardiac vein. The blood finally drains into the right atrium.
The posterior descending artery is often (85%) a branch of the right coronary artery.
The sinus node artery is a branch of the right coronary artery in 60% of cases.
The AV node is supplied by the posterior descending coronary artery.
ARRHYTHMIAS
Atrial flutter most commonly presents with 2:1 block, which means atrial rate of 300
but ventricular rate of 150. Ischaemic chest pain may occur due to the tachycardia.
Carotid sinus massage can sometimes terminate or slow the tachycardia.
DC cardioversion should be performed if the patient is cardivascularly unstable.
Atrial flutter is commoner in patients with dilated left atrium or in
congenital/structural heart disease.
Differentiating SVT from VT
Features that favour VT are :
QRS of > 140ms,
cannon a waves on JVP
fusion and/or capture beats
dissociated p waves,
history of ischaemic heart disease,
right bundle branch block with left axis deviation,
concordance of the QRS complexes in the chest leads
HR >170 beats per minute.
In a patient who is stable with sustained ventricular tachycardia, the options are
intravenous lignocaine, intravenous amiodarone. IV magnesium sulphate (
mmols or 5g) is often helpful in helping to cardiovert. If the patient were unstable
then he needs to be DC cardioverted immediately (with or without general
anaesthetic).
The criteria for ICD insertion are:
1) patients with LVEF <40% with non sustained VT
MRCPASS NOTES 2
