S1 occurs at the beginning of systole. It's the "lub" of the "lub-dub" a provider hears when listening to the heart by placing their stethoscope on a person's chest wall. Diastole is when the ...

The "lub" (systolic sound) happens when part of the heart contracts, and the mitral and tricuspid valves close. The "dub" (diastolic sound) occurs when part of the heart relaxes, and the aortic ...

A regular heartbeat makes a “lub-dub, lub-dub” sound ... or a temperature change. A systolic murmur begins during the first heart sound and ends before the second heart sound.

There are two phases in the cardiac cycle: systole and diastole ... It is much easier to hear the first two noises, “lub” and “dub,” which are high pitched. The third and fourth sounds ...

S1 occurs at the beginning of systole and is the "lub" of a heartbeat. S2 occurs at the beginning of diastole and is the "dub" of a heartbeat. If S3 is present, it occurs right after S2 in diastole.

The aortic valve allows blood to leave the heart and travel through the aorta, which is the largest artery in the body. Aortic stenosis is when this heart valve narrows and doesn’t open fully.