Aortic Stenosis: -The Aortic valve is located between the LF ventricle and the aortic artery. -It is tricusped valve and its closure represent S2. -Aortic stenosis is mainly caused by degeneration and calcification of the aortic valve. *The main causes of A.S: -Rheumatic heart diseases. -Senile aortic degeneration. -Congenital bicuspid aortic valve (1% of the population). -Congenital aortic stenosis. *The pathophysiology of A.S: When there is aortic stenosis there will be mechanical blood flow obstruction from the LF ventricle and the aorta and the will lead to LF ventricular hypertrophy and decreased coronary aortic blood flow which produce angina like pain. Also with the progression of the case and due to the inadequate coronary blood supply the heart will fail to increase the cardiac out-put in cases of demand as in case of exercise and this will cause exercise related Hypotension and syncope. Severe cases can cause pulmonary edema, fatigue and weakness. -Now in interesting fact is the normally all the patients with aortic stenosis are asymptomatic but when the symptoms start to appear they deteriorate rapidly. *Physical examination reveals: 1-Prominent 4th heart sound. 2-Soft 2nd heart sound. 3-Carotid thrill. 4-Aortic ejection click. 5-Ejection systolic murmur best heard at the aortic area. 6-Pulsless Tardus which is delayed or decreased in the aortic up-stroke. *Diagnosis of A.S: 1-CXR will show cardiomegaly, pulmonary congestion, LF ventricular hypertrophy and can show the severely calcified valve. 2-ECG can show LF ventricular hypertrophy, LBBB, Strain pattern, down slopping ST segment, Inverted T wave and LF axial deviation. 3-Echo can help to measure the thickness and the degree of the stenosis of the valve and also can demonstrate LF ventricular hypertrophy. *Treatment of A.S: 1-Prophylactic antibiotics to prevent endocarditis. 2-Surgery is indicated in fit patients who have valve diameter less than 0.8 cm and require valve replacement surgery but patients who are not fit for such surgical procedure they can have percutanouse trans femoral balloon valvulopasty. 3-For patients who develop Atrial fibrillation we can give anti-coagulants.
Posted on: Sun, 07 Jul 2013 12:36:52 +0000
Trending Topics
Recently Viewed Topics
© 2015