Hi guys, I'm getting confused with the S3 and S4 heart sounds and their relationships to cardiac problems. So FA says that S3 is associate with dilated CHF, is this the same same dilated cardiomyopathy? Why would you get an S3 sound if the LV is dilated anyway---it happens at the end of rapid ventricular filling, but can anyone expalin why the sound appears? Thanks so much people, it is much appreciated!!!