When is an S3 heart sound heart? What is an S3 heart sound caused by? What may it be indicative of?
An S3 heart sound occurs early in diastole (right after S2). In young ppl and athletes, its normal. Indicates presence of CHF in older adults.
It is caused by the result of vibrations within the ventricular walls due to a sudden deceleration of blood flow into the left ventricle from the left atrium. Pt has a thin-walled, dilated left ventricle with generalized decrease vigor of contraction.
When is an S4 heart sound heart? What is an S4 heart sound caused by? What may it be indicative of?
S4 is heart in late diastole just prior to the first heart sound. S4 is caused by oscillation of the blood and cardiac chambers caused by atrial contraction (Dr. Shannon def).This sound is produced by an increase in stiffness of the left ventricle due to scar tissue formation hich may be a manifestaion of CAD. Can also be caused by left ventricular hypertrophy as with HTN or aortic stenosis (web definition)