The third heart sound (S3) is a low-frequency, brief vibration occurring in early diastole at the end of the rapid diastolic filling period of the right or left ventricle (Figure 24.1) Synonymous terms include: ventricular gallop, early diastolic gallop, ventricular filling sound, and protodiastolic gallop.

The third heart sound or S3 is a rare extra heart sound that occurs soon after the normal two "lub-dub" heart sounds (S 1 and S 2). S 3 is associated with heart failure.

S3 is a low-pitched sound (25–50Hz) which is heard in early diastole, following the second heart sound. The following synonyms are used for it: ventricular gallop, early diastolic gallop, protodiastolic gallop, and ventricular early filling sound.

Caused by inflammation of the pericardial sac with or without fluid.

The S3 occurs during the rapid filling phase of early diastole (the y descent of the jugular venous waveform), 0.14-0.22 seconds after S2 (MUCH farther from S2 than a widely split S2). Unlike the split S2, the S3 is best heard over the apex of the heart using the bell of the stethoscope.

Although having only intermediate sensitivity, the S3 is a highly specific finding among older adults with heart failure. Identification of an S3 by routine auscultation can be problematic given the chaotic and noisy ED environment, patient comorbid conditions, and intolerance of ideal positioning for auscultation.

Jul 10, 2016 · S3 gallop is a low frequency, early to mid-diastolic sound. In the normal heart during normal sinus rhythm, diastolic filling of the ventricle across the atrioventricular valves occurs in two phases, early and atrial filling. There are characterized by Doppler echocardiography:

A triple rhythm in diastole is called a gallop and results from the presence of a S3, S4 or both. Description: Both sounds are low frequency and thus best heard with the bell of the stethoscope. Location: If originating from LV Usually best heard over apex with patient in the left lateral position Softer during inspiration If originating from RV

Auscultation: What is S3? When is it a normal physiological finding? S3 = Early in diastole. Quiet, low pitched, difficult to hear. Physiological S3 common finding in children, pregnant women in 3rd trimester & young adults to ~40y/0 Auscultation: What is S4? When is it a normal finding? Late in diastole. Quiet & difficult to hear.

DDx: Heart Failure S3 -heard early in Diastole; very low frequency (25-50 Hz) - Tenn - e - ssee -- S1-S2-S3 DDx: Heart Failure