Myocardial Ischemia in Severe Aortic Regurgitation Despite Angiographically Normal Coronary Arteries

Abstract

Patients with severe aortic regurgitation frequently present with angina pectoris. The exact pathophysiology for angina in aortic regurgitation is not clear. Left ventricular hypertrophy and myocardial blood supply-demand mismatch have been the suggested mechanisms to explain ischemia. However, no conclusive clinical study exists to define the incidence of ischemia in patients with severe aortic regurgitation and normal coronary arteries. We, therefore, investigated the frequency of myocardial ischemia in relation to left ventricular hypertrophy or dilatation in patients with severe aortic regurgitation and normal coronary arteries. We reviewed the medical records of all patients (n = 311) with aortic valve replacement due to aortic regurgitation between 2007 and 2010. We selected subjects with normal coronary arteries (n =182) for the study purpose, and we identified 35 patients who underwent myocardial perfusion scintigraphy prior to the coronary angiography (19 female and 16 male subjects; age 45.0 ± 8.9 years). Left ventricular hypertrophy and dilatation were detected in 9 (26%) and 5 (14%) patients, respectively. Myocardial perfusion scintigraphy showed evidence of ischemia in 10 (29%) patients with normal coronary arteries. The presence of ischemia did not relate to the presence of left ventricular hypertrophy and/or dilatation. As a potential mechanism, aortic regurgitation causes backflow of blood from the aorta into the left ventricle, hence disturbs coronary flow dynamics. In conclusion, myocardial ischemia is common (nearly one-third) among patients with severe aortic regurgitation even in the absence of coronary obstruction, left ventricular hypertrophy and/or dilatation.

Subendocardial Ischemia Caused by Acute Severe Aortic Regurgitation Due to Aortic Root Dissection: A Case Report and Literature Review

“…We reported a patient diagnosed with subendocardial ischemia due to acute severe AR complicating aortic root dissection. Subendocardial ischemia reportedly occurs in patients with chronic severe AR and normal coronary arteries (2). The causes are increased oxygen demand due to tachycardia and increased LV end-diastolic pressure as well as a decreased coronary blood flow and oxygen supply due grade blood flow from the left main trunk to the aorta during LV diastole in a patient with acute severe AR (4).…”

“…In contrast, there are few reports describing the electrocardiogram (ECG) findings when dissection has not progressed to coronary ostium. Acute AR may reduce myocardial perfusion by rapidly increasing the left ventricular (LV) end-diastolic pressure and decreasing the coronary blood flow ( 2 ).…”

An Atypical Presentation of Decubitis Angina in a Patient with Coronary Artery Disease and Aortic Regurgitation: Case Report

“…Aortic regurgitation has also been implicated in the pathogenesis of decubitis angina. 8 The eventual outcome of these associations is an imbalance of oxygen supply and demand in the myocardium. Disturbed coronary flow dynamic due to the backflow of blood from the aorta into the left ventricle during diastolic phase has been referred to be the mechanism of myocardial ischemia even in the absence of coronary stenosis.…”

Pulsation of catheter during coronary angiography: Is it a sign of severe aortic regurgitation?

“…Myocardial ischemia may cause oxygen supply/demand mismatch because of ventricular hypertrophy or dilatation, as well as retrograde coronary artery flow [8,9]. Retrograde coronary flow and diastolic narrowing of the epicardial coronary artery have been reported in severe aortic regurgitation [10].…”