Heart sounds are important clues that help doctors understand how well the heart is working. These sounds can show different problems in the heart's cycle. The heart makes specific sounds when the heart valves close during different stages of pumping blood.

Normal Heart Sounds:

1. S1 (First Heart Sound): This sound happens when the mitral and tricuspid valves close at the start of ventricular systole, which is when the heart contracts to pump blood out.

2. S2 (Second Heart Sound): This sound occurs when the aortic and pulmonary valves close at the start of ventricular diastole, which is when the heart relaxes and fills with blood.

There are also some other normal heart sounds:

• S3 (Third Heart Sound): This sound often comes from the heart filling with blood quickly early on in diastole. It can be normal, especially in kids and athletes.

• S4 (Fourth Heart Sound): This sound happens when the atria contract. It can be heard more often in people with high blood pressure or heart disease when the heart's stiffness increases.

Abnormal Heart Sounds:

When heart sounds are not normal, they can point to various heart problems:

1. Systolic Murmurs: These sounds are common and can signal issues with the heart valves, such as:

   • Aortic Stenosis: This produces a special "ejection" sound. About 15% of people over 75 may have this condition.
   • Mitral Regurgitation: This creates a "holosystolic" murmur and is found in about 2% of the population.

2. Diastolic Murmurs: These may suggest problems like:

   • Aortic Regurgitation: This has a "blowing" sound and is often seen in people with rheumatic fever.
   • Mitral Stenosis: This is marked by a "low-pitched" murmur and is found in about 0.7% of people.

3. Increased S3 and S4 Sounds: A loud S3 sound can mean heart failure, especially in people showing symptoms (it happens in up to 80% of these cases). An audible S4 sound may indicate issues like left ventricular hypertrophy or lack of blood flow, and it’s more common in older adults.

4. Extra Sounds:

   • Clicks: These are linked to mitral valve prolapse and can occur in 2-3% of people.
   • Pericardial Rub: This sound is often heard when there’s inflammation around the heart, a condition called pericarditis.

Summary:

Listening to heart sounds gives doctors valuable information about how the heart is working. If they hear abnormal sounds like murmurs or different heart sounds, it can lead to more tests and treatment. This shows just how important it is for doctors to listen to the heart during check-ups.