Coronary microvascular dysfunction in patients with INOCA was associated with significantly higher arterial stiffness compared to controls (peripheral AIx 38.4% vs 28.7%; p=0.03).
Observational (n=90)
Is arterial stiffness and sympathetic nervous system activity associated with coronary microvascular dysfunction in patients with ischemia and no obstructive coronary arteries?
In patients with INOCA, arterial stiffness is independently associated with coronary microvascular dysfunction, suggesting a potential pathophysiological link and therapeutic target.
Absolute Event Rate: 38.4% vs 28.7%
p-value: p=0.03
Abstract Background According to the literature, chronic angina in patients with ischemia and non-obstructive coronary arteries (INOCA) is associated with an elevated risk of cardiovascular events. This study aims to explore the potential relationship between arterial stiffness, increased sympathetic nervous system (SNS) activity, and coronary microvascular dysfunction (CMD). Methods All participants underwent functional coronary angiography with coronary circulation physiology assessment. Coronary flow reserve (CFR) and the index of microvascular resistance (IMR) were measured. Patients with coronary microvascular dysfunction (CMD) were classified into two subgroups: structural and functional endotypes (CFR 2.5 and IMR ≥ 25 were considered abnormal). Additionally, in all participants, arterial stiffness was assessed using the aortic augmentation index (AIx), derived from the analysis of central pulse waveforms, recorded by applanation tonometry directly from the radial artery. Muscle sympathetic nerve activity (MSNA) was evaluated using microneurography. We analyzed all outcomes using multivariable linear mixed models, adjusting for potential confounders, including age, sex, optic disc size, axial length, and blood pressure (BP) parameters. Results A total of 90 patients were included in the study. 46 patients without CMD, control group female, 54%, mean age: 62.7±7.1 years and 44 patients with CMD, CMD group (female, 68%, mean age: 59.9±9.2 years). In CMD group, 32% had a normal value of IMR, indicating functional CMD endotype, while 68% had an abnormal IMR, indicating structural endotype. Significant increases in arterial stiffness were identified in CMD patients vs controls as measured by peripheral AIx (38.4±9.8 vs 28.7±10.9%, p=0.03). There was no independent association between PWA and CMD endotypes. Increased AIx levels remained significantly associated with CMD after adjusting for several CVD-related risk factors. There was no independent association between PWA and CMD endotypes. MSNA burst frequency (bursts/min) after adjustment for age, gender, e-GFR was found increased in CDM participants (49.4 ± 11 versus 42.1±12 bursts/min in control subjects), p=0.55. While not statistical significance, there exists a discernible trend towards higher MSNA in CMD patients compared to control group. Conclusion Arterial stiffness, as measured by the augmentation index, is independently associated with CMD, even after adjusting for demographic factors and multiple atherosclerotic risk factors. Further prospective studies are warranted to evaluate whether radial artery tonometry can serve as a reliable risk stratification tool in this specific patient population. Additionally, targeted therapies aimed at reducing systemic arterial stiffness may hold promise for improving clinical outcomes in patients with ischemia and no obstructive coronary artery disease.CMD evaluation with bolus thermodilution Correlation between CMD & art. stiffness
Sakalidis et al. (Sat,) conducted a observational in Ischemia and no obstructive coronary arteries (INOCA) (n=90). Coronary microvascular dysfunction (CMD) vs. Patients without CMD was evaluated on Arterial stiffness measured by peripheral aortic augmentation index (AIx) (p=0.03). Coronary microvascular dysfunction in patients with INOCA was associated with significantly higher arterial stiffness compared to controls (peripheral AIx 38.4% vs 28.7%; p=0.03).