Diabetes mellitus and coronary microvascular function in asymptomatic patients with severe aortic stenosis and nonobstructed coronary arteries

Abstract

Background and aim: Coronary flow reserve is impaired in asymptomatic patients with aortic stenosis and has a prognostic value. We investigated whether the type II diabetes mellitus additionally impairs microvascular circulation assessed by coronary flow reserve in patients with asymptomatic severe aortic stenosis, normal left ventricular ejection fraction and nonobstructed coronary arteries. Methods: A total of 128 patients, mean age of 66.35 ± 10.51 (58.6% males), with severe aortic stenosis and normal left ventricular ejection fraction were enrolled in this study. Patients with diabetes mellitus, those who were treated for diabetes mellitus or had documentation confirming the diagnosis of diabetes mellitus, were considered. All patients underwent coronary angiography and had no obstructive coronary disease (defined as having no stenosis >50% in diameter), standard transthoracic Doppler-echocardiographic study and adenosine stress transthoracic echocardiography for coronary flow reserve measurement. Results: Diabetes mellitus was present in 26 patients (20.31%). There was no significant difference in aortic stenosis severity between diabetic and non-diabetic patients [aortic valve area (0.81 ± 0.18 vs 0.85 ± 0.15 cm 2 ) and V max (4.20 ± 0.57 vs 4.21 ± 0.48 m/s)]. Mean coronary flow reserve in diabetic patients was 1.98 ± 0.48, while mean coronary flow reserve in non-diabetic patients was 2.64 ± 0.54 (p < 0.01). Diabetes mellitus was independent predictor of coronary flow reserve [B = −0.636, 95% confidence interval (−0.916 to −0.368), p < 0.001]. Conclusion: Diabetes mellitus additionally impairs coronary microvascular function in asymptomatic patients with severe aortic stenosis and nonobstructed coronary arteries.

Aortic stenosis and diabetes mellitus: An ominous combination

“…56 One potential mechanism in the association of diabetes and AS is that diabetes additionally impairs coronary microvascular function in asymptomatic patients with severe AS and non-obstructed coronary arteries. 92 It has been shown that impaired microvascular function in asymptomatic patients with severe AS is a predictor of a worse outcome in severe AS patients. [93][94][95] Within the PRIMID AS population, it was shown that patients with a lower myocardial perfusion reserve were associated with development of symptoms in the medium term, 29 and this may be worsened in patients with diabetes.…”

“…The reduction in microvascular circulation in AS patients may also be responsible for myocardial ischaemia and potentially fatal arrhythmias that are observed in diabetic AS patients with normal or non-obstructive epicardial coronary circulation. 29,92,96…”

Defining Coronary Flow Patterns: Comprehensive Automation of Transthoracic Doppler Coronary Blood Flow

“…For example, in adult humans with type II diabetes mellitus (T2DM), multiple studies have demonstrated a reduction in coronary flow reserve (CFR) or CFVR compared to matched controls despite being asymptomatic 7 – 9 . Previous studies by our laboratory have shown that the CM in young T2DM murine and porcine models undergoes early inward hypertrophic remodeling 10 , 11 , and others have demonstrated functional deficits 12 , 13 .…”

Diabetes Is Associated With Rapid Progression of Aortic Stenosis: A Single-Center Retrospective Cohort Study

“…In AS patients, diabetes was associated with a worse prognosis. It has been reported that diabetes can impair coronary microvascular function in patients with asymptomatic AS ( 34 ). Some studies have shown that diabetes has an adverse effect on hypertrophic remodeling and is associated with reduced systolic function ( 35 , 36 ).…”