AUTHOR=Zhang Han , Shi Kuangyu , Fei Mengyu , Fan Xin , Liu Lu , Xu Chong , Qin Shanshan , Zhang Jiajia , Wang Junpeng , Zhang Yu , Lv Zhongwei , Che Wenliang , Yu Fei 

TITLE=A Left Ventricular Mechanical Dyssynchrony-Based Nomogram for Predicting Major Adverse Cardiac Events Risk in Patients With Ischemia and No Obstructive Coronary Artery Disease

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2022.827231

DOI=10.3389/fcvm.2022.827231

ISSN=2297-055X

ABSTRACT=Background: The risk stratification of patients with ischemia and no obstructive coronary artery disease (INOCA) remains suboptimal, this study aims to establish a left ventricular mechanical dyssynchrony (LVMD)-based nomogram to improve the present situation.
Methods: Patients with suspected coronary artery disease (CAD) were retrospectively enrolled and divided into three groups: normal (stenosis < 50%, without myocardial ischemia), INOCA (stenosis < 50%, summed stress score>4, summed difference score≥2) and Obstructive CAD (stenosis≥50%). LVMD was defined by ROC analysis. INOCA group were followed up for the occurrence of major adverse cardiac events (MACEs: cardiovascular death, non-fatal myocardial infarction, revascularization, stroke, heart failure, rehospitalization related to angina). Nomogram was established by multivariate Cox regression analysis.
Results: Among 334 patients (118[35.3%] INOCA), LVMD parameters were significantly higher in INOCA group versus normal group, but did not differ between Obstructive CAD group. In INOCA group, 27(22.9%) MACEs occurred during a 26-months median follow-up. Proportion of LVMD were significantly higher with MACEs both under stress (63.0% vs 22.0%, P<0.001) and rest (51.9% vs 20.9%, P=0.002). Kaplan-Meier analysis revealed significantly higher rate of MACEs (stress Log-rank P = 0.002; rest Log-rank P < 0.001) in LVMD patients. Multivariate Cox regression analysis showed that stress LVMD (HR, 3.82; 95%CI, 1.30-11.20; P = 0.015) was an independent predictor of MACEs. The internal bootstrap resampling approach indicates the C-index of nomogram was 0.80 (95%CI 0.71-0.89) and the AUC for 1,3 years risk prediction was 0.68 (95% CI 0.46-0.89), 0.84 (95% CI 0.72-0.95). 
Conclusion: LVMD-based nomogram might provide incremental prognostic value and improve the risk stratification in INOCA patients.