Introduction

Takotsubo syndrome (TS) is defined as a transient dysfunction of the left ventricle in the absence of coronary artery obstruction which is characterized by different types of wall motion abnormalities, in most cases of the apical and mid-ventricular segments. Several studies, especially based on echocardiographic myocardial strain analysis, already showed a relevant impairment of global and segmental longitudinal strain in patients with TS. However, the difference of global and segmental strain analysis between patients with TS and other entities of myocardial infarction without obstructive coronary artery disease (MINOCA) is still incompletely understood. Thus, the aim of this study was to compare global and segmental myocardial strain in cardiac magnetic resonance imaging (CMR) in patients with TS and patients with different entities of MINOCA.

Methods

We retrospectively performed myocardial strain analysis in CMR in patients with TS (n= 12) and different entities of MINOCA (unclear n= 20, ischemic n=16, inflammatory/infiltrative/toxic n=11). In all patients, global longitudinal strain (GLS), global circumferential strain (GCS) and global radial strain (GRS) analysis of the left ventricle were performed. Furthermore, segmental longitudinal (SLS), circumferential (SCS) and radial strain (SRS) of all segments according to the AHA 16/17-segment model was accomplished.

Results

GLS was impaired in patients with TS (GLS: -11.54±2.3%) compared to patients with different entities of MINOCA (GLS: -14.06±2.84% in MINOCA of ischemic cause, p=0.019; -13.96±2.49% in MINOCA of unclear cause, p= 0.019; -13.63±2.36% in MINOCA of inflammatory/infiltrative/toxic cause, p= 0.073). Similar data were obtained for GCS and GRS.

Interestingly, the decrease in global strain analysis was mostly driven by a decrease in segmental strain analysis of segments 13, 14 and 17, which are the apical segments supplied by the left anterior descending coronary artery (segment 13: SLS: -10.28±3.15%; segment 14: SLS:-10.41±3.06%; segment 17: SLS:-11.49±4.24%) when compared to other forms of MINOCA (segment 13: SLS: -14±2.6% in MINOCA of unclear cause, p= 0.004; SLS:-13.2±3.71% in MINOCA of ischemic cause, p=0.031; SLS: -13.73±3.07% in MINOCA of inflammatory/ infiltrative/ toxic cause, p=0.020, similar data for segment 14 and 17 as well as for SCS and SRS).

Conclusion

Global strain analysis as determined in CMR is significantly impaired in patients with TS compared to patients with MINOCA of other entities, which may be explained by a decrease in myocardial strain of apical segments supplied by the left anterior descending coronary artery.