ANSWERS WILL BE POSTED TOMORROW 16/2/17 by 17:00
A 67-year old male complains of shortness of breath when we walks a flight of stairs at his home.
Upon auscultation, you can hear a diminished first heart sound followed by an ‘ejection click’. The second heart sound is normal but during early diastole, a crescendo-decrescendo murmur is heard.
1. What is the most likely diagnosis in this patient ?
2. List the potential etiologies of this condition.
3. Outline the pathophysiology of this condition.
4. What two basic clinical signs are typically found to be positive ?
5. Which investigations would you request in this patient ?
6. How would you manage this patient ?
7. Comment on the overall prognosis.
1. Aortic Regurgitation
2. Causes of Aortic Regurgitation
- Pressure in the left ventricle falls below pressure in the aorta, hence the aortic valve is unable to close completely.
- This causes blood leak from the aorta into the left ventricle and some of the blood that was already ejected, regurgitates back into the heart !!
- This regurgitant flow causes a decrease in the diastolic pressure in the aorta, and therefore an increase in the pulse pressure.
- Hence, there is decreased effective forward flow in aortic insufficiency.
4. Two Clinical Signs
- Watson’s water hammer pulse or collapsing pulse describes a pulse that is bounding and forceful, rapidly increasing and subsequently collapsing.
- Wide Pulse Pressure
Routine Blood Tests: CBC, ESR & CRP, U&E and Cr, Electrolytes, Cardiac Enzymes (Troponin and CK-MB)
ECG: Arrhythmias and the rate of tachycardia. It will also rule out or diagnose Myocardial Ischaemia.
Chest X-ray: May not show cardiomegaly, a characteristic finding for chronic Aortic Regurgitation. Possible evidence of pulmonary oedema with bilateral basal shadowing, pleural effusions at costophrenic angles, and fluid in lung fissures.
Trans-thoracic echocardiogram: To diagnose and evaluate extent of valvular disease.
Trans-oesophageal echocardiogram: Performed only if aortic dissection is suspected. usually there is chest pain that radiates to the back.
For chronic Aortic Regurgiation that is stable and asymptomatic, vasodilators are usually used. Benefit seen in using Angiotensin II receptor blockers, Acetylcholinesterase Inhibitors, nifedipine and hydralazine to decrease afterload.
Surgery is indicated if ejection fraction falls to 50% or lower. Aortic Valve replacement is done as an open-heart procedure using aortic valve homograft. In the case of severe acute aortic insufficiency, all individuals should undergo surgery.
The risk of death in individuals with aortic insufficiency, dilated ventricle, normal ejection fraction who are asymptomatic is about 0.2 % per year. Risk increases if the ejection fraction decreases or if the individual develops symptoms.
Aortic regurgitation carries a mortality of 10-20% in patients who do not undergo aortic valve replacement.