Murmurs Flashcards
What do S1 and S2 represent?
S1 - closure of mitral and tricuspid valves
between S1 and S2 = SYSTOLE
S2 - closure of aortic and pulmonic valves
between S2 and next S1 = DIASTOLE
What are the 4 anatomical auscultation sites?
- Aortic = 2nd ICS RUSB
- Pulmonic = 2nd ICS LUSB
- Tricuspic = 4th ICS
- Mitral = 5th ICS MCL (apex)
(erb’s point - 3rd ICS LSB = best point for auscultation of murmurs)
Aortic Stenosis - main facts
- ventricles contract against partially closed aortic valve
- murmur starts a few milliseconds into systole when the valve snaps open producing a systolic murmur with an EJECTION CLICK
- crescendo-decrescendo murmur (diamond shaped)
- radiates to the neck/carotids (as these are some of the first branches of the aorta)
Aortic Stenosis - clinical features
Aortic stenosis
Syncope
Angina
Dyspnoea
High and low (crescendo-descrescendo)
Ejection click
Age (main cause - degenerative calcification)
Radiates to carotids
Take out (replace) or repair (valvuloplasty)
•chest pain
•dyspnoea
•exertional syncope
(SAD = syncope, angina, dyspnea)
Severe AS
- narrow pulse pressure
- slow rising pulse
- soft or absent S2
- S4
- thrill
- LVH or failure
Causes of aortic stenosis
- degenerative calcification (most common cause in older patients > 65 years)
- bicuspid aortic valve (most common cause in younger patients < 65 years)
- post-rheumatic disease
- subvalvular: HOCM
Aortic Stenosis - management
- if asymptomatic then observe the patient is general rule - echo follow up etc.
- if symptomatic and stable –> aortic valve replacement (either open surgery or transcatheter)
- clinically unstable or unfit for replacement –> balloon valvuloplasty = percutaneous procedure - balloon is forcefully inflated across aortic valve to relieve stenosis
What other medical management must be offered post valve replacement?
- long-term infective endocarditis antibiotic prophylaxis
- long-term anticoagulation - indicated in those patients who have had aortic valve replacement using prosthetic mechanical valves.
Pulmonic stenosis?
- same idea as AS –> systolic crescendo-decrescendo murmur with ejection click
- however best heard on pulmonic valve area and does not radiate to carotids
Causes of ejection systolic murmur
- aortic stenosis
- pulmonary stenosis, hypertrophic obstructive cardiomyopathy
- atrial septal defect, tetralogy of Fallot
Mitral regurgitation - main facts
MVP, post-MI (causes) Insufficiency of heart (leads to HF) Treat HF symptoms Radiates to axilla All of systole (holosystolic) Lelf atrial dilatation Repair over replacement (usually)
- holo/pan systolic
- “flat murmur” - same pitch throughout systole bc in chronic MR the atrium expands during systole to become more compliant
- radiates to axilla (blood flow going back up)
- S1 may be quiet as a result of incomplete closure
- Severe MR may cause a widely split S2
S1 —Brrrrrr— S2
What is the main complication as MR progresses?
As the degree of regurgitation becomes more severe, the body’s oxygen demands may exceed what the heart can supply and as a result, the myocardium can thicken over time. While this may be benign initially, patients may find themselves increasingly fatigued as a thicker myometrium becomes less efficient, and eventually go into irreversible heart failure.
- can lead to S3
Mitral regurgitation - causes
- Age-related
- Following coronary artery disease or post-MI: if the papillary muscles or chordae tendinae are affected by a cardiac insult, mitral valve disease may ensue
- Mitral valve prolapse
- Infective endocarditis: vegetations from the organisms colonising the valve prevent it from closing properly
- Rheumatic fever
- Congenital
MR - symptoms
- Most patients with MR are asymptomatic
- Symptoms tend to be due to failure of the left ventricle, arrhythmias or pulmonary hypertension
- This may present as fatigue, shortness of breath and oedema.
MR - investigations
- ECG may show a broad P wave, indicative of atrial enlargement
- Cardiomegaly may be seen on chest x-ray, with an enlarged left atrium and ventricle
- Echocardiography is crucial to diagnosis and to assess severity
MR - management
- Medical management in acute cases involves nitrates, diuretics, positive inotropes and an intra-aortic balloon pump to increase cardiac output
- If patients are in heart failure, ACE inhibitors may be considered along with beta-blockers and spironolactone
- In acute, severe regurgitation, surgery is indicated –> balloon valvuloplasty, annuloplasty (tighten ring) or vavle replacement
- The evidence for repair over replacement is strong in degenerative regurgitation, and is demonstrated through lower mortality and higher survival rates
- When this is not possible, valve replacement with either an artificial valve or a pig valve is considered
