- Diseases, Disorders & Conditions
Hemodynamic Disturbances, Prognosis And Treatment Of Aortic Regurgitation (Aortic Incompetence)
Valve Regurgitation Insufficiency
The commonest cause of isolated aortic regurgitation is congenital bicuspid aortic valve. Such valves may be primarily incompetent or further damage by infective endocarditis may make them so. In subaortic stenosis, also varying degrees of AR may be present. In ventricular septal defect, the aortic cusps may prolapsed into the defect giving rise to AR. Diseases such as syphilis, aknkylosing spondylitis, Reiter’s disease, rheumatoid arthritis, annuloaortic ectasia, aneurysm of the aorta and aortic dissection which affect the root of the aorta can all produce abnormality in valve closure resulting in varying degrees of aortic regurgitation.
Infective endocarditis produces and worsen aortic regurgitation. Acute reupture of the valve cusps in infective endocarditis leads to acute AR. Blunt trauma to the chest and acute elevation of systemic blood pressure also account for a few of the cases.
In AR, part of the blood pumped out into the aorta leaks back into the left ventricle during diastole. The proportion of the cardiac output regurgitating may vary widely. The left ventricle received blood from the left atrium and the aorta during diastole and this leads to diastolic overfilling. The ventricle undergoes dilatation and hypertrophy. Stroke volume is increased. The systolic blood pressure may go up. Peripheral vasodilatation develops in moderate to severe cases and the peripheral resistance falls. Regurgitation of aortic blood and fall in peripheral resistance result in considerable lowering of the diastolic pressure. The pulse pressure is markedly increased. The heart compensates and maintains the cardiac output for considerable periods by dilatation and hypertrophy, but ultimately left ventricular failure develops.
Course, Prognosis And Treatment
Course and prognosis
Mild cases usually do not progress. However, infective endocarditis may complicate even mild cases. Moderate cases progress over a number of years to severe forms. The left ventricle progressively enlarges. These may proceed to pulmonary hypertension and congestive heart failure.
Mild cases do not require any definitive line of treatment except prophylaxis for infective endocarditis. Moderate and severe cases should be advised to restrict heacy physical activity. Cases with congestive heart failure require treatment with digoxin, diuretics and other measures. Valve replacement is required in severe cases. Repair of the aortic root and valve replacement are indicated in cases with aortic root disease. In AR presenting as emergency, valve replacement may be required as an urgent life saving measure.
© 2014 Funom Theophilus Makama