Medical treatment in aortic stenosis

Patients with asymptomatic aortic stenosis have relatively good immediate prognosis despite the severity of valve stenosis, and conservative management is adequate in them.These  patients should be kept under regular follow up.Development of angina, syncope, symptoms of low cardiac output or heart failure are all associated with  poor prognosis and they indicate the need for surgery.

Take the following precaution

1. Avoid strenuous physical activity and competitive sports in patients with severe valvular stenosis  (valve area <1 cm 2 ).It should be avoided even if the  patient is in asymptomatic stage. 

2. Take special precaution to avoid dehydration and hypovolemia as it may reduce cardiac output.

3. Drugs used for the treatment of hypertension or coronary artery disease, including beta blockers and ACE inhibitors, are safe for asymptomatic patients if they have  preserved left ventricular systolic function.

Drugs for symptom relief in aortic stenosis

1. Nitroglycerin can relieve the angina pectoris in patients with coexistent CAD.

2. Retrospective studies have shown that those patients with degenerative calcific AS if treated with HMG-CoA reductase inhibitors(statins)show slower progression of aortic leaflet calcification and lesser reduction of aortic valve area.However,certain randomized prospective studies with high-dose atorvastatin or combination simvastatin/ ezetimibe donot exihibit favourable valve related outcomes.But statins are useful in reducing CAD risk.

Need for Infective endocarditis prophylaxis

Infective endocarditis prophylaxis is required in AS patients with a previous history of endocarditis.

Aortic stenosis correlation of clinical finding and pathogenesis

Aortic stenosis correlation of clinical finding and pathogenesis

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Murmur of Aortic stenosis

The murmur of Aortic stenosis is characteristically

1. Ejection (mid)systolic murmur which  commences shortly after the S1,it increases in intensity and reach  a peak towards the middle of ejection, and it ends just before closure of aortic valve. 
2. It is a diamond shaped systolic murmur.
3. It is characteristically low-pitched, rough and rasping in character. 
4. The murmur is  loudest at the base of the heart, most commonly in the second right intercostal space.
5. Aortic stenosis murmurs is transmitted upward along the carotid arteries. Occasionally this murmur is transmitted downward and to the apex, it may be confused with the systolic murmur of MR. This phenomenon is called Gallavardin effect.
6. In patients with severe obstruction and normal cardiac output, the murmur is at least grade III to VI.
7. If patient  has mild degree of obstruction or in those  patients with severe stenosis with heart failure and low cardiac output the transvalvular flow rate are reduced, the aortic stenosis murmur may be soft and brief. 

Heart sounds and murmur in Aortic stenosis

S1 is  normal.
S2 may be normal or  paradoxical splitting of S2 may be present as Aortic stenosis increases in severity, LV systole may be prolonged so a2 and P2 may become synchronous, or aortic valve closure may sometimes  follow pulmonic valve closure, resulting in  paradoxical splitting of S2 .
A2 may be heard in patients with Aortic stenosis who have pliable valves calcification diminishes the intensity of A2.
S4 may be audible at the apex and it reflects the presence of LV hypertrophy and an elevated LV end-diastolic pressure.
S3 occurs late in the course,as LV dilates and severe systolic dysfunction occurs.

Pathophysiology of Aortic stenosis

In Aortic stenosis the cardiac output is initially maintained at the cost of a increasing pressure gradient across the aortic valve. This causes hypertrophy of LV (left ventricle) and compromise the coronary flow. Patients may develop angina even in the absence of coronary heart disease. Thus the fixed cardiac output limit the increased cardiac output required during exercise. Finally LV (left ventricle) fails to overcome the outflow tract obstruction and pulmonary oedema will develop. Those with aortic stenosis typically remain asymptomatic for many years but rapidly deteriorate when symptoms develop, and death ensues within 3 to 5 years.

Read related topics  - Aortic Stenosis

1. How will you assess the severity of aortic stenosis
2. Heart sounds in Aortic stenosis
3. Pulse in aortic stenosis
4. Differentiate between valvular, supravalvular, subvalvular aortic stenosis
5. What are the clinical examination findings in Aortic Stenosis 
6. Symptoms of aortic stenosis 
7. What are the causes of aortic stenosis
8. Medical treatment in aortic stenosis
9. Aortic stenosis correlation of clinical finding and pathogenesis
10. Murmur of Aortic stenosis
11. Heart sounds and murmur in Aortic stenosis 
12. Causes of Aortic stenosis

Causes of aortic stenosis vary depending on the age of the patient.
Common causes in Infants, children, adolescents
Congenital aortic stenosis

• Congenital subvalvular aortic stenosis
• Congenital supravalvular aortic stenosis

Common causes in Young adults to middle-aged

• Calcification and fibrosis of congenitally bicuspid aortic valve
• Rheumatic aortic stenosis

Common causes in Middle-aged to elderly

• Senile degenerative aortic stenosis
• Calcification of bicuspid valve
• Rheumatic aortic stenosis

Normal aortic valve VS Aortic valve stenosis

What is Aortic regurgitation

Normally the aortic valve close when the left ventricle pump blood into aorta. In Aortic regurgitation valve fails to close completely and blood leak back into left ventricle during diastole. So during diastole left ventricle receive blood from  left atrium and leaking aorta.