II. Pathophysiology
- S4 represents rapid active ventricular filling
- Occurs as atria contract during late diastole
- Outside of normal causes (see below), typically represents a stiff ventricle that resists dilation
- Associated with Ventricular Hypertrophy and Diastolic Dysfunction
III. Signs
- S4, S1, S2 Sound like "Ten-ne-see" (dub-lub-dub)
IV. Causes
- Normal in athletes and the elderly
- Stiff Left Ventricle
- Hypertension
- Diastolic Dysfunction
- Coronary Artery Disease
- Aortic Stenosis
- Cardiomyopathy
- Ventricular Hypertrophy
V. Resources
- University of Michigan Heart Sound and Murmur Library