What is a continuous murmur?

What is a continuous murmur?

Continuous murmur is not a murmur which is continuously heard throughout systole and diastole, though some like the murmur patent ductus arteriosus is like that. By definition, a continuous murmur begins in systole and continues without interruption, through the second heart sound into diastole. It can cover either part of diastole or the whole of diastole.

A murmur which disappears completely before the next first heart sound is still considered continuous if the systolic part continues without interruption during the second heart sound. Highest intensity of continuous murmur is usually heard in rupture of sinus of Valsalva (RSOV) into the right ventricular outflow tract (RVOT). Murmur of RSOV to RVOT has diastolic augmentation as the track gets compressed in systole. PDA murmur peaks around the second heart sound.

Reference

1. Ginghină C, Năstase OA, Ghiorghiu I, Egher L. Continuous murmur–the auscultatory expression of a variety of pathological conditions. J Med Life. 2012 Feb 22;5(1):39-46. Epub 2012 Mar 5. PMID: 22574086; PMCID: PMC3307079.