The fourth heart sound (S4), also known as the “atrial gallop,” occurs just before S1 when the atria contract to force blood into the left ventricle. If the left ventricle is noncompliant ...

A fourth heart sound develops when LV hypertrophy becomes severe and limits diastolic filling. A third heart sound is often present due to the increased early diastolic filling into a compliant ...

the carotid upstroke may be brisk or double (traditionally called the spike and dome carotid upstroke); palpation of the precordium may reveal a palpable fourth heart sound, a sustained apical ...