Myocardial energetic efficiency is depressed in ischemia with non-obstructive coronary arteries

Abstract Background Ischemia with non-obstructive coronary arteries (INOCA) is incompletely understood. Depressed myocardial energetic efficiency index (MEEi), the ratio between external work and myocardial oxygen consumption, has been shown in heart failure. However, MEEi in INOCA has not been explored. Purpose To test whether MEEi is associated with INOCA. Methods We included 125 patients (56% women, age 62±9 years) with exercise-induced chest pain and non-obstructive coronary arteries (stenosis <50%) by coronary computed tomography angiography (CCTA). Stroke volume (SV) and left ventricular (LV) mass were assessed by echocardiography. MEEi was calculated as (systolic blood pressure (SBP) x SV) / (SBP x heart rate) and normalized for LV mass. LV hypertrophy was defined as LV mass index >46.7 g/m2.7 in women and >49.2 g/m2.7 in men. Myocardial ischemia was detected by myocardial contrast stress echocardiography. Coronary artery plaque burden was measured as plaque volume by CCTA. Results In univariable regression analysis, stress-induced ischemia, male sex, diabetes, hypertension, LV hypertrophy, lower LV ejection fraction and higher SBP were associated with MEEi (all p<0.05). There were no associations with age, obesity or coronary artery plaque burden. MEEi was lower in patients with stress-induced ischemia (n=66) compared to patients without ischemia (0.47±0.16 vs. 0.54±0.21 ml/sec x g–1, p=0.026). In multivariable linear regression analysis, MEEi remained associated with stress-induced myocardial ischemia after adjustment for cardiovascular risk factors, SBP, LV hypertrophy, LV ejection fraction and coronary artery plaque burden (R2 0.26, p<0.001, Table). Conclusion MEEi is depressed in patients with INOCA. Our results suggest that myocardial ischemia negatively influences MEEi in patients with non-obstructive coronary arteries. Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): Western Norway Regional Health Authority, University of Bergen

Download Full-text

Coronary artery plaque burden is a predictor of myocardial ischemia in non-ST elevation myocardial infarction in both genders

European Heart Journal ◽

10.1093/eurheartj/eht307.p437 ◽

2013 ◽

Vol 34 (suppl 1) ◽

pp. P437-P437

Author(s):

I. Eskerud ◽

E. Gerdts ◽

J. E. Nordrehaug ◽

M. T. Lonnebakken ◽

Keyword(s):

Myocardial Infarction ◽

Coronary Artery ◽

Myocardial Ischemia ◽

St Elevation Myocardial Infarction ◽

Plaque Burden ◽

Coronary Artery Plaque ◽

St Elevation

Download Full-text

Intracoronary acetylcholine spasm testing: differences in epicardial coronary artery response between smooth and atherosclerotic coronary arteries

European Heart Journal ◽

10.1093/ehjci/ehaa946.1519 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

R Gollwitzer ◽

V Martinez Pereyra ◽

A Seitz ◽

R Bekeredjian ◽

U Sechtem ◽

...

Keyword(s):

Coronary Artery ◽

Myocardial Ischemia ◽

Coronary Arteries ◽

Univariate Analysis ◽

Coronary Artery Spasm ◽

Signs And Symptoms ◽

Funding Source ◽

Epicardial Coronary Artery ◽

Microvascular Spasm ◽

Test Result

Abstract Background Coronary artery spasm is an established cause for angina pectoris. Epicardial coronary spasm may occur in patients with obstructed as well as unobstructed coronary arteries. Previous studies have suggested that epicardial plaque/atherosclerosis is a prerequisite for the development of epicardial spasm. The aim of the present study was to compare the results of intracoronary acetylcholine (ACh) testing in patients with signs and symptoms of myocardial ischemia with completely smooth versus atherosclerotic yet unobstructed epicardial arteries. Methods Between 2008 and 2016 a total number of 617 patients with signs and symptoms of myocardial ischemia yet unobstructed epicardial arteries (<50% epicardial stenosis) was included in the present study (mean age 61±11, 61% female). All patients underwent invasive diagnostic coronary angiography followed by intracoronary ACh testing according to a standardized protocol. The ACh-test was considered “positive” in the presence of (a) angina, ischemic ECG shifts during the test and ≥75% focal or diffuse coronary diameter reduction (“epicardial coronary artery spasm”) or (b) ischemic ST-shifts and angina in the absence of epicardial spasm (“microvascular spasm”). All angiograms were assessed regarding any visible epicardial plaque/atherosclerosis in a blinded fashion and patients were categorized into those with completely smooth versus those with atherosclerotic coronary arteries. The analysis included 179 patients (29%) with epicardial spasm and 172 patients with microvascular spasm (28%). The remaining 266 patients (43%) had an uneventful or an inconclusive ACh-test result. Results There were 389 patients (63%) with completely smooth epicardial arteries. The remaining 228 patients (37%) had non-obstructive epicardial plaques <50%. Patients with smooth arteries developed epicardial spasm in 24%, microvascular spasm in 32% and a negative/inconclusive test result in 44% of cases. Patients with atherosclerotic arteries developed epicardial spasm in 38%, microvascular spasm in 21% and an inconclusive/negative test result in 41% of cases. On univariate analysis the presence of epicardial atherosclerosis was associated with epicardial spasm (p=0.006) whereas this was not the case for microvascular spasm (p=0.094). Multivariate analysis revealed the presence of epicardial atherosclerosis (OR 1.921, CI 1.285–2.871, p=0.001) as well as female sex (OR 1.526, CI 1.024–2.274, p=0.038) as independent predictors for epicardial spasm. Conclusion In patients with signs and symptoms of myocardial ischemia yet unobstructed coronary arteries the presence of epicardial atherosclerosis is an independent predictor for the occurrence of epicardial spasm but not microvascular spasm on acetylcholine testing. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): Robert-Bosch-Stiftung, Berthold-Leibinger-Stiftung

Download Full-text

Role of peroxisome proliferators-activated receptor-gamma in advanced glycation end product-mediated functional loss of voltage-gated potassium channel in rat coronary arteries

European Heart Journal ◽

10.1093/ehjci/ehaa946.1277 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

W Li ◽

S.D Gao ◽

B Hua ◽

Q.B Liu ◽

H.R Liu ◽

...

Keyword(s):

Oxidative Stress ◽

Coronary Artery ◽

Coronary Arteries ◽

Funding Source ◽

Peroxisome Proliferators ◽

Advanced Glycation ◽

Coronary Vasodilation ◽

Voltage Gated ◽

Kv Channel ◽

Ppar Γ

Abstract Background Voltage-gated K+ (Kv) channels in coronary artery smooth muscle cells (CSMCs), especially the major specific Kv1 subfamily, contribute to coronary artery vasodilation. Advanced glycation end products (AGEs) have been strongly implicated in diabetes-related cardiovascular complications. Our previous study showed AGEs can impair Kv channel-mediated coronary vasodilation by reducing Kv channel activity. However, its underlying mechanism remains unclear. Purpose Here, we used isolated rat small coronary arteries (RSCAs) and primary CSMCs to investigate the effect of AGEs on Kv channel-mediated coronary vasodilation and the possible involvement of peroxisome proliferators-activated receptor (PPAR)-γ pathway. Methods RSCAs and primary CSMCs were isolated, cultured and treated with bovine serum albumin (BSA), AGE-BSA, alagrebrium (ALA, AGE cross-linking breaker), pioglitazone (PIO) and/or GW9662, and then divided into the following groups: DMEM, BSA, AGE, AGE+ALA, AGE+PIO, and AGE+PIO+GW9662. Kv channel-mediated coronary vasodilation was analyzed using wire myograph. Histology and immunohistochemistry of RSCAs were performed. Western blot was used to detect the protein expression of RAGE, the major Kv1 channel subunits expressed in CSMCs (Kv1.2/1.5), PPAR-γ, and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-2 (NOX-2). Results AGEs markedly reduced forskolin-induced Kv channel-mediated vasodilation of RSCAs by interacting with the receptor for AGEs (RAGE), and ALA or PIO significantly reversed this effect. In both RSCAs and primary CSMCs, AGEs decreased Kv1.2 and Kv1.5 channel protein expression, inhibited PPAR-γ expression, increased RAGE and NOX-2 expression. Treatment with ALA or PIO partially reversed the effects of AGEs on Kv1.2/Kv1.5 expression, accompanied by elevation of PPAR-γ level and diminished oxidative stress. Conclusion AGE/RAGE axis-induced inhibition of PPAR-γ pathway and enhancement of oxidative stress may contribute to AGEs-mediated Kv channel dysfunction and coronary vasodilation in RSCAs. Our results may provide new insights into developing therapeutic strategies to manage diabetic vasculature. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): National Natural Science Foundation of China; Natural Science Foundation of Beijing (7172059)

Download Full-text

Reproducibility of Noncalcified Coronary Artery Plaque Burden Quantification From Coronary CT Angiography Across Different Image Analysis Platforms

American Journal of Roentgenology ◽

10.2214/ajr.13.11225 ◽

2014 ◽

Vol 202 (1) ◽

pp. W43-W49 ◽

Cited By ~ 23

Author(s):

Shane Oberoi ◽

Felix G. Meinel ◽

U. Joseph Schoepf ◽

John W. Nance ◽

Carlo N. De Cecco ◽

...

Keyword(s):

Image Analysis ◽

Coronary Artery ◽

Ct Angiography ◽

Coronary Ct Angiography ◽

Plaque Burden ◽

Coronary Artery Plaque ◽

Coronary Ct

Download Full-text

Medial-ABC: an algorithm for the correspondence between myocardium and coronary artery mesh models based on the medial axis of coronary artery

Journal of Computational Design and Engineering ◽

10.1093/jcde/qwaa054 ◽

2020 ◽

Vol 7 (6) ◽

pp. 736-760

Author(s):

Jehyun Cha ◽

Joonghyun Ryu ◽

Jin-Ho Choi ◽

Deok-Soo Kim

Keyword(s):

At Risk ◽

Clinical Practice ◽

Coronary Artery ◽

Myocardial Ischemia ◽

Coronary Arteries ◽

Medial Axis ◽

Patient Specific ◽

Abc Algorithm ◽

Myocardium At Risk ◽

Mesh Models

Abstract The role of coronary arteries is to supply sufficient blood to myocardium. Obstruction of coronary arteries limits blood supply and causes myocardial ischemia or acute myocardial infarction, a major cause of human death. Hence, the quantification of the regional amount of heart muscle subtended by obstructed coronary arteries is of critical value in clinical medicine. However, conventional methods are inaccurate and frequently disagree with clinical practice. This study proposes a novel medial-axis-based correspondence (Medial-ABC) algorithm to find the correspondence between myocardium and coronary artery in order to segment regional myocardium at risk subtended by any potentially obstructed coronary artery. Given the triangular mesh models of coronary artery and myocardium, the proposed algorithm (i) computes the medial axis of coronary artery, (ii) finds the correspondence using the medial axis of coronary artery, and (iii) segments the coronary artery and myocardium. The proposed algorithm provides a robust mathematical linkage between myocardium at risk and supplying coronary arteries so that ischemic myocardial regions can be accurately identified. Hence, both the extent and severity of myocardial ischemia can be quantified effectively, efficiently, and accurately. Furthermore, the constructed mesh model of segmented coronary artery and myocardium can be post-processed for applications such as building optimization models of cardiac systems. The CardiacVis program, which implements the Medial-ABC algorithm, is freely available at Voronoi Diagram Research Center (http://voronoi.hanyang.ac.kr/software/cardiacvis) and will be an invaluable tool for quantitative patient-specific risk stratification in clinical practice.

Download Full-text