Left ventricular global longitudinal strain in patients with coronary microvascular dysfunction and preserved ejection fraction: A single-center study

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 (