Cardiology Flashcards
Aetiology of Aortic Stenosis
The most likely aetiology underlying aortic stenosis is degeneration of a bicuspid (or unicuspid) congenital valve. The risk factors involved are the same as those for ischaemic heart disease.
Calcific disease of a trileaflet valve.
Other causes include rheumatic heart disease.
Summary of Finding in Aortic Stenosis
In the absence of other conditions, the patient is usually in sinus rhythm (atrial fibrillation is unusual).
It is unusual for the blood pressure to be very high in severe aortic stenosis.
In moderate-severe aortic stenosis the carotid pulse is often of small volume with a slow rise and a plateau pulse may be present.
The apex beat may be pressure loaded and NOT markedly displaced.
There may be a palpable thrill at the base of heart and/or in the aortic area.
On auscultation an ejection systolic murmur is heard, loudest in the aortic area and radiating to the neck.
The murmur is usually graded as 3 or 4/6 (unless stroke volume is low when the murmur may then be soft).
Indicator of Severity in Aortic Stenosis
- A small volume, slow rising, plateau carotid pulse.
- Narrow pulse pressure
- The presence of an aortic thrill.
- A long late peaking ejection systolic murmur.
- A loud murmur (grade 4 or greater) has a high specificity for severe AS
○ However, most patients with severe stenosis have a grade 3 murmur, and many have only a grade 1 or 2 murmur. - The presence of an S4, indicating reduced compliance of the left ventricle.
- Paradoxical splitting of S2.
- The presence of left ventricular failure.
- Pressure loaded apex beat.
- Soft/absent aortic component of the second heart sound
- Signs of pulmonary hypertension
What is Gallavardin Phenomenon?
The murmur of aortic stenosis may be heard at the apex
This is known as Gallavardin phenomenon.
In this phenomenon, the harsh murmur of aortic valvular stenosis may change in quality and become musical at the apex.
This can cause confusion in differentiating the murmur from that of mitral regurgitation, however they can be differentiated by the murmur quality (i.e. ejection systolic in aortic stenosis versus pansystolic in mitral regurgitation).
Severe Aortic Stenosis Murmur
The murmur is ejection systolic.
It is heard throughout systole, indicating that a pressure gradient is present throughout. The murmur peaks late in systole.
These are all indicators of the severity of aortic stenosis.
Mild Aortic Stenosis Murmur
In mild aortic stenosis, the carotid pulse is normal and the ejection systolic murmur is short with an early peak.
Aetiology of Mitral Regurgitation
Mitral regurgitation aetiology can be primary due to mitral valve disease or secondary due to left ventricular pathology
Primary Mitral Valve Disease
Mitral valve degeneration (e.g. myxomatous mitral valve disease). Rheumatic mitral valve disease. Involvement in infective endocarditis. Congenital heart disease. Ruptured chordae tendineae. Infarcted papillary muscles.
Secondary Mitral Regurgitation
Left ventricular dilatation e.g. dilated cardiomyopathy
Mitral Regurgitation Physical Finding (Summary)
The patient may be in atrial fibrillation.
A displaced, dyskinetic apex beat.
Soft S1.
Presence of an S3.
An apical thrill.
A pansystolic murmur that radiates to the axilla.
Evidence of heart failure.
Evidence of pulmonary hypertension and tricuspid regurgitation.
Indicator of Mitral Regurgitation Severity
Left ventricular dilatation.
A soft S1.
The presence of pulmonary hypertension.
A split S2.
The presence of an S3.
Complication of left ventricular failure.
Small pulse volume (very severe mitral regurgitation).
Auscultation in significant Mitral Regurgitation
Pansystolic murmur.
A soft S1.
A loud S2 suggests the presence of pulmonary hypertension.
An S3 generated by turbulent left ventricular blood flow.
CXR Findings for Mitral Regurgitation
- Left atrial enlargement (double heart border, splayed carina, straightening/convexity of the left heart border indicating enlarged left atrial appendage)
- Pulmonary hypertension (enlarged pulmonary trunks, especially on the left)
- Enlarged left ventricle (increased cardiothoracic ratio)
- Right ventricular enlargement (filling of the retrosternal space >1/3rd)
Common aetiologies of Tricuspid Regurgitation
Tricuspid regurgitation is commonly secondary to right ventricular dilatation.
It may also result as a complication of tricuspid valve infective endocarditis. [Right sided infective endocarditis may be a complication of intravenous cannulation and/or intravenous drug use.]
It may also result as a complication of pacemaker insertion and of frequent trans-jugular cardiac biopsies, as may occur post heart transplant.
Summary of findings in Tricuspid Regurgitation
Tricuspid regurgitation is most readily clinically diagnosed on the basis of peripheral signs, i.e. elevated JVP with prominent V wave & rapid Y descent (pulsatile earlobe), pulsatile liver and often the presence of a right ventricular heave and pulmonary hypertension.
A pansystolic murmur is best heard at the left lower sternal edge and as with all right sided murmurs is louder on inspiration.
Patients with chronic tricuspid regurgitation may develop portal hypertension and ascites (cardiac cirrhosis).
Peripheral oedema may also be present.
Tricuspid regurgitation commonly accompanies mitral regurgitation and pulmonary hypertension.
JVP in Tricuspid Regurgitation
large v-wave with a rapid y-descent causing earlobe pulsation
What is the finding of apex beat in TR without mitral valve disease?
Normal character and location
Parasternal lift/heave is usually indicates …?
right ventricular hypertrophy (rarely gross left atrial hypertrophy)
Common aetiology of Aortic Regurgitation
These can be divided into valve and aortic root pathologies
Valve pathology in Aortic Regurgitation
Rheumatic heart disease (although unlikely in isolated aortic regurgitation).
Congenital with or without ventricular septal defect (VSD).
As a complication of infective endocarditis.
Aortic root pathology in Aortic Regurgitation
Aortic root dissection.
In association with ankylosing spondylitis.
As a result of syphilitic aortitis.
As a complication of Marfan’s syndrome.
Peripheral signs of Aortic Regurgitation
Signs of a wide pulse pressure (note that severe aortic regurgitation may not be accompanied by a wide pulse pressure as left ventricular end-diastolic pressure rises).
Blood pressure measurement (wide systolic-diastolic difference).
A collapsing/water-hammer pulse.
Quincke’s sign (nail bed pulsation).
Head bobbing.
Pistol shot femoral artery sounds (systolic and diastolic sounds).
A displaced apex beat.
A diastolic thrill at the left lower sternal edge.
Auscultation findings of Aortic Regurgitation
A S3 maybe present.
An early decrescendo diastolic murmur loudest at the left lower sternal edge and best heard at end of expiration, with the patient leaning forward.
An Austin Flint mid-diastolic murmur may be heard at the apex in severe aortic regurgitation.
There may be evidence of left ventricular failure.
An ejection systolic murmur may be heard, caused by the large stroke volume and does not necessarily indicate co-existing aortic stenosis.
Indicators of Aortic Regurgitations Severity
A wide pulse pressure with associated collapsing pulse.
The presence of a long decrescendo diastolic murmur (in very severe aortic regurgitation with left ventricular decompensation, the murmur may become soft or absent with equalisation of aortic and ventricular diastolic pressures).
The presence of an S3.
The presence of a soft A2.
The presence of an Austin-Flint murmur.
The presence of left ventricular enlargement.
Apex beat in Aortic Regurgitation
In addition to “volume loaded” other descriptive terms include diffuse and hyperdynamic. These descriptions are in keeping with ventricular dilatation caused by the regurgitant blood and a hyperdynamic left ventricle.
Aetiology of Mitral Stenosis
Rheumatic heart disease is the most common cause, other causes being much less common.
Examples of less common causes include radiation induced and congenital mitral stenosis.