Cardiac Murmur

  • Pansystolic murmurs are audible throughout systole from the first to second heart sounds. It is caused by regurgitation through incompetent atrioventricular valves and by ventricular septal defects. 
  • Murmur of mitral regurgitation is loudest at the cardiac apex and it radiates to the left axilla.
  • Murmur of tricuspid regurgitation and ventricular septal defect are loudest at the left lower sternal edge.
  • Early diastolic murmurs are high pitched and they start immediately after the second heart sound fading away in mid diastole. They are caused by regurgitation through incompetent aortic and pulmonary valves.
  • Murmur of aortic regurgitation radiates from aortic area to the left sternal edge 
  • Pulmonary regurgitation murmur is heard at the pulmonary area. 
  • A young basketball player with a height of 188 cm and armspan 197 cm has a diastolic murmur best heard in second right intercostal space. The likely cause of murmur is Aortic Regurgitation.
  • (This patients arm span is greater than height, which is suggestive of Marfan’s syndrome.Aortic regurgitation as well as diastolic murmur in second right intercostal space are features associated with Marfan’s.).
  • A neonate has central cyanosis and short systolic murmur on the 2nd day of birth.The diagnosis is Transposition of Great Vessels.
  • Acyanotic heart disease with ejection systolic murmur→ ASD, VSD, PDA, Coarctation of aorta.
  • Carey-Coombs Murmur :Heard in patients with acute rheumatic fever.Occurs due to inflammation of mitral valve cusps or excessive left atrial blood flow as a consequence of MR.Soft middiastolic murmur usually follows S3.
  • Austin-flint murmur is a mid-diastolic/presystolic murmur heard in chronic severe AR. The diastolic murmur mimics mitral stenosis and is attributed to mitral valve leaflet vibration or mild obstruction caused by rapid regurgitant flow both from the aortic root and the left atrium.
  • Graham Steele's Murmur - Early diastolic murmur heard over Erb's Point seen in Pulmonic Insufficiency, secondary to Pulmonary Hypertension and Mitral Stenosis.
  • Rytan 's murmur is mid-diastolic (or late-diastolic) murmur that is heard in patients with complete artioventricular heart block.
  • Docks murmur → Left Anterior Descending (LAD) artery stenosis
  • Mill wheel murmur → Due to air emboli (air in PV cavity)
  • Systolic murmur in TOF is due to Pulmonary Stenosis.
  • The murmur of Aortic Stenosis is characteristically an ejection systolic murmur that occurs in midsystole (starts only shortly after S1 and never with S1) when the ventricular pressure becomes high enough to open the semilunar valve. 
  • Following murmurs may be heard in patients with aortic regurgitation : High-pitched decrescendo diastolic murmur , Soft, low pitched mid distolic rumbling murmur , Mid-systolic ejection flow murmur.
  • Mid diastolic murmur with with presystolic accentuation is typically seen in mitral stenosis.
  • Murmurs of HOCM ,MVP are increased on Valsalva maneuver
  • Murmurs of VSD, MR and AS all decrease in intensity on Valsalva maneuver.
  • A young patient presents with a systolic murmur at the apex. The murmur increases on both handgrip and valsalva maneuver.MVP is the most likely condition.
  • Continuous murmurs result from continuous flow between a high pressure and low pressure area that persists through the end of systole and beginning of diastole.
  • Continuous murmurs are not affected by dynamic auscultation maneuvers like squatting etc.
  • Common Causes of continuous murmurs
  1. Systemic arteriovenous fistula (congenital /acquired)
  2. Coronary arteriovenous fistula 
  3. Anomalous origin of Left coronary artery from pulmonary artery
  4. Communication between sinus of valsalva and right side of heart e (i.e.Ruptured sinus of valsalva into right side of heart)
  5. Coarctation of Aorta : Continuous murmur in the back
  6. Patent Ductus Arteriosus e (PDA)
  7. Surgically created shunts e.g. Blalock-Tausig shunt.
  • The murmur of peripheral pulmonary stenosis is harsh systolic ejection murmur typically preceded by a systolic ejection sound.
  • Cause of new systolic murmur after Acute Myocardial infarction
  1. Papillary muscle dysfunction/rupture (causing severe mitral regurgitation)
  2. Rupture of interventricular septum
  3. Right ventricular infarction and tricuspid regurgitation
  4. Free wall rupture
  5. Left ventricular outflow tract obstruction.
  • The murmur in tetralogy of Fallot relates to the degree of right ventricular outflow obstruction (pulmonic stenosis). It is a harsh ejection systolic murmur resulting from turbulent flow across the stenotic pulmonic valve.
  • Wide fixed splitting of S2 with ejection systolic murmur in left 2" intercostal space points towards the diagnosis of atrial septal defect.. Presence of left axis deviation indicates an ostium primum ASD.
  • Shunt murmur in patent ductus arteriosus is a continuous machinery murmur.Ductus arteriosus may cause a machinary murmur by its patency..
Cardiovascular manifestations of thyrotoxicosis:
  1. Sinus tachycardia is the most common manifestation of Thyrotoxicosis.
  2. Midsystolic murmur heard best at left sternal border with or without Systolic ejection click.
  3. Means lerman scratchy: It is a systolic scratchy sound heard at the 2nd left intercostal space during expiration. It is thought to result from rubbing of hyperdynamic pericardium against the pleura.
  4. Irregularly irregular pulse.
  • Severity of mitral stenosis is determined by duration of Diastolic Murmur.
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