Prevalence of the third and fourth heart sound in asymptomatic adults.

The prevalence of abnormal diastolic heart sounds in asymptomatic adults has been the subject of great debate. The authors determined the prevalence of an electronically detected S3 and S4 in 1329 asymptomatic adults between the ages of 18 and 94. The authors also investigated the relationship between abnormal diastolic heart sounds, age, and electrocardiography. The overall prevalence of S3 was 10.0% (95% confidence interval [CI], 8.1%-12.2%), S4 was 15.6% (95% CI, 13.2%-18.2%), and both S3 and S4 were 3.5% (95% CI, 2.4%-5.0%). Using multinomial logistic regression, increasing age was found to decrease the odds of an S3 being heard (odds ratio, 0.96; 95% CI, 0.95-0.96) and increase the odds of an S4 being heard (odds ratio, 1.04; 95% CI, 1.03-1.05). We conclude that the prevalence of an S3 is increased earlier in life, that an S4 is less common than previous studies suggest, and that its detection, even in the elderly, should not be ignored.