S4 Gallop

The S4 occurs in late diastole, just before S1, coinciding with atrial contraction (the a wave in the jugular venous waveform). It is generally present when the heart is so stiff that it is reliant upon a significant amount of filling via atrial contraction. Like the split S1, the S4 gallop is best heard over the apex of the heart. However, unlike the split S1, it is best heard with the bell of the stethoscope because of its low pitch.

Card Tutorial

Patient 3

This is a middle-aged man with poorly-controlled diabetes mellitus who was admitted to the hospital with a necrotizing soft tissue infection involving the back of his neck. He was noted to be tachycardic with a right-sided S4 gallop. No definitive explanation for this finding was determined.

S4 Gallop

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