Protective Effect of Aortic Stenosis on the Coronary Arteries. Hypothetic Considerations to an Old Enigma

Abstract

A literature overview of angiographic studies has shown that the prevalence of significant coronary disease in patients with aortic stenosis (AS) varies from 20 to 60%. Early necropsy studies suggested that patients with AS had a lower than expected incidence of coronary artery disease (CAD), originating the concept of a protective effect of AS on the coronary arteries. The myth of AS protection against CAD would be better explained as endothelium-myocardial interaction (crosstalk) protection triggered by left ventricular overload. Therefore, the cGMP/NO pathway induced by the AS overload pressure would explain the low incidence of CAD, which is compatible with the amazing natural long-term evolution of this cardiac valve disease.

Speculative Considerations about Some Cardiology Enigmas

“…This hypothesis would explain the low incidence of CAD, which is compatible with the incredibly natural long-term AS evolution [23]. This theory is illustrated in Fig.…”

“…The enigma of AS protection against CAD would be better explained by an endothelium/myocardial interaction (crosstalk) triggered by the left ventricular overload, inducing the cGMP/NO pathway. This hypothesis would explain the low incidence of CAD, which is compatible with the incredibly natural long-term AS evolution [ 23 ]. This theory is illustrated in Fig.…”

“…This theory is illustrated in Fig. ( 6 ), and its keys point would be summarized: 1) Increased coronary diameters are systematically observed in association with ventricular hypertrophy secondary to aortic valve disease and chronic systemic hypertension; 2) In patients with AS, right coronary artery dimensions remain unchanged, while left ventricle hypertrophy is associated with an increase in left coronary dimensions; 3) When left ventricle hypertrophy severity increases, coronary artery size increase would be insufficient, and; 4) After valve replacement, the enlarged left coronary artery size decreases at an equal rate with the muscle mass regression [ 23 ].…”

“…Otherwise, as in most cases of acute rheumatic fever, pneumonia occurs with inflammation, causing the alveolar-capillary membrane thickening that protects against the acute lung edema (Fig. 4 ) [ 22 ].…”

“…While CABG may favorably influence the long-term outcome in patients undergoing aortic prosthesis surgery, however, this information is not yet applicable to TAVI, because the profile of its long-term outcome is still unknown. This information is crucial, considering the advent of transcatheter valves [ 23 ].…”