Residual alterations of cardiac and endothelial function in patients who recovered from Takotsubo cardiomyopathy

Abstract

Introduction: Takotsubo cardiomyopathy (TCM) is characterized by transient left ventricle dysfunction.

Hypothesis: A residual cardiac and endothelial dysfunction is present in patients who recovered from TCM.

Methods: In this single-center prospective study, patients with prior TCM were included and followed for 6.4 ± 1.6 years. All underwent comprehensive cardiac function assessment, including tissue Doppler imaging (TDI) and 2-dimensional strain (2DS) echocardiography at their first visit. The number of circulating endothelial progenitor cells and levels of proangiogenic vascular endothelial growth factor (VEGF) and its receptor (VEGF-R) were measured. All measurements were compared with healthy controls.

Results: Forty-two women (age 58. ±8.6 years, LVEF 58.1 ± 6.1%) comprised the TCM group. Patients post-TCM had significantly lower early velocities E' (6 (5.0-8.0) vs. 9 (7.0-11.0) cm/s, p = .001) by TDI and higher E/E' ratio (p = .002), lower LV global average longitudinal strain (LGS) (-18.9 ± 3.5% vs. -21.7 ± 2.3%, p = .002) and RV LGS (-20.1 ± 3.9% vs. -23.4 ± 2.8%, p = .003) were evident. There was a trend toward a higher VEGF-R (p = .09) along with decreased VEGF/VEGF-R ratio representing inadequate VEGF production. In-hospital mortality was not reported and only two non-cardiac deaths occurred at long-term follow-up.

Conclusions: Altered TDI and 2DS indices suggest residual biventricular myocardial injury in post-TCM patients with the apparent LV function recovery. Inappropriate production of VEGF and VEGF-R were observed, suggesting a possible underlying endothelial dysfunction in these patients.

Keywords: Takotusubo cardiomyopathy; endothelial dysfunction; longitudinal global strain; tissue Doppler imaging.

FIGURE 1

Comparison 2‐dimentional strain values between patients with prior Takotusubo cardiomyopathy (TCM) and controls. LGS, longitudinal global strain; LV, left ventricle; RV, right ventricle

FIGURE 2

Comparison of VEGF‐R, VEGF and VEGF/VEGF‐R between the TCM patients and controls. Box plots of VEGF‐R (3A), VEGF (3B) and VEGF/VEGF‐R (3C) concentration. The band at the middle of each box plot represents the median, and the bottom and top of the boxes represents the 25th, 75th percentiles. VEGF, vascular endothelial growth factor; VEGF‐R, vascular endothelial growth factor receptor