| Sound | Timing relative to dub | Key feature | |-------|------------------------|--------------| | Opening snap (MS) | After dub | High-pitched, early diastole | | S3 | After dub (mid-diastole) | Low-pitched, “slosh” | | S4 | Before dub (late diastole) | Low-pitched, “a” wave | | Ejection click | Before dub (early systole) | High-pitched, follows S1 | | Pericardial knock | After dub | Early diastolic, constrictive pericarditis |
The room went silent, save for the hiss of the ventilator and the slow, rhythmic beep of the monitor signaling asystole. A flat line. Silence. dub heart sound
"Nurse," Thorne said, his voice low. "What's the current BP?" | Sound | Timing relative to dub |