Left ventricular global longitudinal strain in patients with coronary microvascular dysfunction and preserved
Lior Zornitzki1,2, Yotam Barlev3, Sheizaf Gefen4,3
1Division of Cardiology, Tel Aviv Sourasky Medical Center affiliated with Tel Aviv University School of Medicine, Tel Aviv, Israel. lior.zoz@gmail.com.
Background:
Left ventricular global longitudinal strain (LVGLS) detects myocardial injury. Reduced LVGLS is associated with worse outcomes in several cardiovascular conditions. Currently, there is a paucity of evidence regarding LVGLS in patients with coronary microvascular dysfunction (CMD).
Aims:
We assessed whether LVGLS is reduced in patients with CMD.
Methods:
We included patients who underwent clinically indicated invasive assessment of coronary microvascular function with ejection fraction >50%. LVGLS measurements were performed using semi-automated speckle-tracking software and are presented in absolute values. Associations between LVGLS, echocardiographic parameters, and coronary microvascular function were assessed using univariate and multivariable analyses.
Results:
Ninety-three patients were included in the analysis (58% female; median age 66 years, interquartile range [IQR] 58-74) of whom 49 (52.6%) had evidence of CMD. Median ejection fraction and LVGLS for the study cohort were 60% and 16.2%, respectively. Patients with CMD had worse LVGLS compared to those without CMD (15.0% [IQR 13-17] vs. 17.9% [IQR 15-21]; P = 0.04). Patients with structural CMD (14.4%; IQR 12.3-16.6) vs. functional CMD (16.5%; IQR 14.3-19.4), and no CMD (17.9%; IQR 15.2-21.3) had lower LVGLS (P for trend = 0.001). Reduced LVGLS (<17.5%) was associated with CMD (odds ratio [OR], 3.08; 95% confidence interval [CI], 1.28-7.43) and remained significant after multivariable adjustment (adjusted OR, 3.61; 95% CI, 1.35-9.68; P = 0.01).
Conclusions:
Patients with CMD and preserved ejection function have lower LVGLS compared with patients without CMD, with worse LVGLS among patients with structural vs. functional CMD. Reduced LVGLS might emerge as an early non-invasive marker for CMD.
