Evaluation of non-invasive myocardial work in Takotsubo cardiomyopathy

Abstract

Tako-tsubo cardiomyopathy(TTC) is characterized by transient left ventricular(LV) wall motion abnormalities(WMA). However, whether systolic performance fully recover is unclear. Non-invasive myocardial work (MW) is a new index of global and regional myocardial performance never described in this setting. To assess global and regional MW in apical TTC. 50 patients with typical TTC(mean age 77 ± 10 y, 47 women) were prospectively enrolled and underwent a transthoracic echocardiography within 24 h of admission and a median of 32 days at follow-up. MW is derived from the non-invasive strain-pressure loop obtained from the 2D strain data, integrating non-invasive arterial pressure. Constructive MW(CMW), MW index(MWI), MW efficiency(MWE), and wasted work(WW) were measured. Hospital complications(HC) were defined as a composite of heart failure, right ventricular extension, and LV apical thrombus. A control group of 24 patients matched for age and sex without overt cardiovascular disease served as a comparative group. In the TTC group, global and regional MW improved significantly between the two examinations (global, regional apical and medial CMW, MWI, MWE, WW, and regional basal CMW, and MWI, all P < 0.01). The acute apical–basal gradient of MW inverted at FU. In TTC, global CMW and MWI were significantly correlated to acute LV systolic function parameters, and were significantly impaired in patients with HC( n = 13, all, P < 0.01). At FU, despite total recovery of WMA, global and regional MW was significantly reduced in TTC by comparison to the control group ( P < 0.01 for all components), although hemodynamics, LV ejection fraction, and 2D global longitudinal strain were similar (all P = NS). Global and regional myocardial performance is transiently impaired in typical TTC and significantly associated to HC. Despite total recovery of WMA, subtle dysfunction of myocardial performance persist at FU.