Cardiovascular examination Part 4

The murmur of mitral stenosis has virtually no radiation and is only heard at the apex. Pulmonary regurgitation and tricuspid stenosis murmurs also have very little radiation.
The murmur of aortic regurgitation radiates down the left sternal border, that of aortic stenosis to the neck (right carotid artery especially), and tricuspid regurgitation murmurs radiate to the lower right sternal border, epigastrium and/or the 5th ICS in the mid left hemithorax. (link)

Acyanotic lesions with left to right shunt are much more common (at least 40% of all congenital heart defects) than cyanotic heart disease (<10%) and are rarely detected soon after birth as pulmonary vascular resistance usually needs to drop (minimum at 3 months) before the clinical features of right to left shunts become obvious. An enlarged heart (or either ventricle) indicates a clinically significant shunt. They consist of ASD, VSD and patent ductus arteriosus. Truncus ateriosus is a single vessel arising from both ventricles and does not have a left to right shunt. (link)

The murmur of a PDA is best heard over the left first intercostal space.  (link)

The apex beat is not usually displaced in an ASD. (link)

The brain is the most commonly affected organ from thromboembolism from left sided native valve endocarditis. The lung is the most commonly affected organ from right sided native valve endocarditis. (link)

Infective endocarditis due to IVDU is usually right sided and does not usually have the peripheral features of left sided endocarditis (Osler’s nodes. Splinter haemorrhages, Roth’s spots, Janeway lesions), unless there is a patent foramen ovale or left sided valve involvement as well. Other common non cardiac features are fever (80%), anaemia (40%), hepatomegaly (30%) and microscopic haematuria (50%). (link)

Osler’s nodes are tender nodules. (link)

Splinter haemorrhages are red for the first 72 hours then become brown. (link)

Osler’s nodes are sterile lesions due to immune complex deposition and usually only last for a few days. More acute forms of endocarditis (eg Staph aureus) usually present early so Osler’s nodes are uncommon. (link)

Janeway lesions are painless lesions that contain bacteria and are more common in acute (esp. Staph Aureus) endocarditis. They may be haemorrhagic and last for days to weeks, but usually have an acral distribution, not an extensor distribution. (link)

Up to 4 splinter haemorrhages are considered normal, as they can occur due to trauma (especially in those that work with their hands). (link)

Bioprosthetic valves are more likely to become stenotic than mechanical valves, but are less prone to ring abscesses that cause valve dehiscence, perivalvular leaks and purulent pericarditis. (link)

An ASD is the most common defect as it includes those people who only have a patent foramen ovale (25% of the population) without significant right to left shunting. The frequency of PFO in the general population has only recently been acknowleged, so many references markedly underestimate the frequency of ASDs as a group. MVP is the most common valve lesion (2-3%) (although you could argue it is a genetically acquired rather than a congenital defect) with bicuspid aortic valves not far behind (2%). VSD is the second most common congenital heart defect (or the most common if you don’t consider a PFO as a defect). (link)

Patients with ASD are usually in sinus rhythm until 30-40 years of age but atrial fibrillation / SVT is common in older patients. There is usually a normal first heart sound but wide and fixed splitting of the second sound due to delayed emptying of the right ventricle. A soft pulmonary systolic murmur with a mid systolic peak due to increased flow over normal pulmonary valve can also occur. A mid diastolic tricuspid flow murmur may be present if the shunt is large but the flow across the atrial septal defect itself does not produce a murmur. (link)

Approximately 25% of patients with a VSD have other cardiac defects.
In about 5% of cases the VSD is just below the aortic valve and may undermine the valve annulus to cause aortic regurgitation. In 5% of cases it is near the junction of the mitral and tricuspid valves, causing regurgitation of these valves. (link)