Physiology of Heart sounds made simple - USMLE Step 1

📌 𝐅𝐨𝐥𝐥𝐨𝐰 𝐨𝐧 𝐈𝐧𝐬𝐭𝐚𝐠𝐫𝐚𝐦:-   / drgbhanuprakash   📌𝗝𝗼𝗶𝗻 𝗢𝘂𝗿 𝗧𝗲𝗹𝗲𝗴𝗿𝗮𝗺 𝗖𝗵𝗮𝗻𝗻𝗲𝗹 𝗛𝗲𝗿𝗲:- https://t.me/bhanuprakashdr 📌𝗦𝘂𝗯𝘀𝗰𝗿𝗶𝗯𝗲 𝗧𝗼 𝗠𝘆 𝗠𝗮𝗶𝗹𝗶𝗻𝗴 𝗟𝗶𝘀𝘁:- https://linktr.ee/DrGBhanuprakash Physiology of Heart sounds made simple - USMLE step 1 Heart sounds are the noises generated by the mechanical actions of the heart, such as the closing of heart valves and the flow of blood through the heart chambers. Understanding the physiology of heart sounds is crucial for medical students preparing for the USMLE Step 1, as it forms the basis for interpreting normal and abnormal heart sounds in clinical practice. There are two main heart sounds, S1 and S2, and two additional sounds, S3 and S4, which may be heard in certain conditions. S1 (First heart sound): S1 is produced by the closure of the atrioventricular (AV) valves, specifically the mitral valve and tricuspid valve, at the beginning of ventricular systole. It marks the onset of ventricular contraction and is generally described as a "lub" sound. S1 is best heard at the apex of the heart, which is typically located at the 5th intercostal space, just medial to the midclavicular line. S2 (Second heart sound): S2 is generated by the closure of the semilunar valves, specifically the aortic valve and pulmonary valve, at the end of ventricular systole. It marks the onset of ventricular relaxation (diastole) and is generally described as a "dub" sound. S2 is best heard at the left upper sternal border (aortic area) and left lower sternal border (pulmonic area). S3 (Third heart sound): S3 is an abnormal heart sound that may be heard in some conditions, such as heart failure. It is produced by the rapid filling of the ventricles during early diastole, causing vibrations in the ventricular walls. S3 is typically described as a "gallop" rhythm and is best heard with the bell of the stethoscope at the apex of the heart with the patient in the left lateral decubitus position. S4 (Fourth heart sound): S4 is another abnormal heart sound that may be heard in certain conditions, such as hypertension or aortic stenosis. It is produced by the vibration of the ventricular walls during atrial contraction in late diastole when the ventricles are resistant to filling. S4 is also described as a "gallop" rhythm and is best heard with the bell of the stethoscope at the apex of the heart with the patient in the left lateral decubitus position. #physiologyofheartsounds #heartsounds #heartsoundsusmle #heartsoundslecture #heartsoundsphysiology #1stheartsound #2ndheartsound #3rdheartsound #4thheartsound #fmge #medicalstudents #usmleprep #usmlepreparation #drgbhanuprakash #mbbslectures #nationalexitexam #usmle #medicalcollege #nationalexittest