Aortic Stenosis Explained | Pathophysiology, Murmur, Echocardiography & Management

Aortic Stenosis Explained | Pathophysiology, Murmur, Echocardiography & Management Aortic stenosis (AS) is one of the most important valvular heart diseases in clinical medicine. It causes obstruction to left ventricular outflow, leading to increased ventricular pressure, compensatory hypertrophy, and potentially heart failure, syncope, and sudden cardiac death. In this comprehensive, practical, high-yield lecture, we explain aortic stenosis from basic pathophysiology to bedside diagnosis, echocardiographic assessment, and evidence-based management. Whether you are a medical student, intern, junior internist, resident, or preparing for USMLE, MRCP, or postgraduate examinations, this video will help you develop a systematic clinical approach to aortic stenosis. 🫀 WHAT YOU WILL LEARN 🔹 1. Definition and Pathophysiology What is aortic stenosis? How narrowing of the aortic valve obstructs left ventricular outflow. Pressure overload, concentric left ventricular hypertrophy, and diastolic dysfunction. Why severe disease can eventually cause systolic dysfunction and heart failure. 🔹 2. Causes of Aortic Stenosis Age-related degenerative calcification. Congenital bicuspid aortic valve. Rheumatic heart disease. Risk factors associated with calcific aortic valve disease. 🔹 3. Clinical Presentation Angina. Syncope or exertional presyncope. Dyspnea and heart failure. Why the classic triad matters clinically. Features suggesting advanced or severe disease. 🔹 4. Physical Examination and Murmur The classic crescendo–decrescendo systolic ejection murmur. Best auscultation area: right second intercostal space. Radiation to the carotids. Delayed carotid upstroke and reduced pulse amplitude in advanced disease. Changes in the second heart sound and other important examination findings. 🔹 5. Diagnosis and Echocardiography Why transthoracic echocardiography is the primary diagnostic test. Peak aortic jet velocity, mean transvalvular pressure gradient, and aortic valve area. How to distinguish mild, moderate, and severe aortic stenosis. Low-flow, low-gradient aortic stenosis and preserved versus reduced ejection fraction. When additional imaging or dobutamine stress echocardiography may be useful. 🔹 6. Management of Aortic Stenosis Monitoring and follow-up for asymptomatic disease. Medical management of associated hypertension, congestion, and comorbidities. Why medications do not remove the mechanical valve obstruction. Indications for aortic valve replacement. Surgical aortic valve replacement (SAVR) versus transcatheter aortic valve implantation/replacement (TAVI/TAVR). How symptoms, valve severity, left ventricular function, age, anatomy, procedural risk, and patient preference influence intervention. 🔹 7. High-Yield Clinical Pearls Why the murmur may become softer when left ventricular function deteriorates. Why symptom assessment is essential in severe aortic stenosis. Why hypotension and excessive preload reduction require particular caution in selected patients. Why symptomatic severe aortic stenosis warrants prompt specialist evaluation. 🎯 WHO SHOULD WATCH? Medical students and interns Junior internists and residents Internal medicine and cardiology trainees USMLE and MRCP candidates Healthcare professionals reviewing valvular heart disease The goal is to connect the underlying physiology with physical examination, echocardiographic interpretation, and practical clinical decisions. If you find this lecture useful, LIKE the video, SUBSCRIBE to the channel, and SHARE it with colleagues. 💬 COMMENT BELOW: Which valvular heart disease should we cover next—mitral stenosis, aortic regurgitation, or tricuspid regurgitation? 📚 Educational disclaimer: This video is intended for medical education and does not replace individualized clinical assessment, specialist consultation, or current clinical guidelines. #AorticStenosis #Cardiology #ValvularHeartDisease #InternalMedicine #MedicalEducation