Gallop rhythm

Third heart sound: genesis and clinical importance

“…Impaired early diastolic relaxation is also caused by intrinsic age-related changes in myocardium, although increased systolic blood pressure with age and subsequent hypertrophy do play a role. Physiological third heart sound is differentiated from the pathological third heart sound primarily in the clinical context [24].…”

Relation of P-S4 interval to left ventricular end-diastolic pressure.

“…Traditionally, the atrial sound has been felt by some to be a reliable physical sign of ventricular dysfunction. [2][3][4][5] Others, however, felt that the mere presence of an atrial sound was of little diagnostic value, since it was frequently recorded by phonocardiograms in normal patients as well as in those with ventricular dysfunction.67 The temporal relation of the atrial sound to the electrocardiogram and first heart sound (Si) has been found to vary with clinical changes in patients with ischaemic heart disease and hypertension. Altered left ventricular pressure volume relations have been implicated as the common denominator in the production of the pathological fourth heart sound.45 More specifically, it has been postulated that decreasing left ventricular distensibility (as reflected by increased left ventricular end-diastolic pressure) is associated with decreasing P wave to atrial sound interval (P-S4) and that it is this mechanism which leads to changes in the P-S4 interval.410-13 It has been shown by McLaurin et al, 14 Barry We performed simultaneous phonocardiography and left ventricular pressure measurements and then used atrial pacing in patients with coronary disease to study the relation of atrial activation, timing of S4 generation, and left ventricular pressure at enddiastole.…”