Response to Letters Regarding Article, “Persistent Long-Term Structural, Functional, and Metabolic Changes After Stress-Induced (Takotsubo) Cardiomyopathy”

Beta-blockers and renin-angiotensin system inhibitors for Takotsubo syndrome recurrence: a network meta-analysis

INTRODUCTION

Takotsubo syndrome (TTS) is an acute heart failure syndrome, featured by transient left ventricular systolic dysfunction. Recurrences of TTS are not infrequent and there is no standard preventive therapy. The aim of this study was to evaluate in a network meta-analysis if beta-blockers (BB) and ACE inhibitors/angiotensin receptor blockers (ACEi/ARBs), in combination or not, can effectively prevent TTS recurrences.

METHODS

We performed a systematic network meta-analysis, using MEDLINE/EMBASE and the Cochrane Central Register of Controlled Trials for clinical studies published between January 2010 and September 2022. We considered all those studies including patients receiving medical therapy with BB, ACEi/ARBs. The primary outcome was TTS recurrence.

RESULTS

We identified 6 clinical studies encompassing a total of 3407 patients with TTS. At 40±10 months follow-up, TTS recurrence was reported in 160 (4.7%) out of 3407 patients. Mean age was 69.8±2 years and 394 patients (11.5%) out of 3407 were male. There were no differences in terms of TTS recurrence when comparing ACEi/ARBs versus control (OR 0.83; 95% CI 0.47 to 1.47, p=0.52); BB versus control (OR 1.01; 95% CI 0.63 to 1.61, p=0.96) and ACEi/ARBs versus BB (OR 0.88; 95% CI 0.51 to 1.53, p=0.65).Combination of BB and ACEi/ARBs was also not effective in reducing the risk of recurrence versus control (OR 0.91; 95% CI 0.58 to 1.43, p=0.68) vs ACEi/ARBs (OR 0.79; 95% CI 0.46 to 1.34, p=0.38)) and vs BB (OR 0.77; 95% CI 0.49 to 1.21, p=0.26).

CONCLUSIONS

Our study did not find sufficient statistical evidence regarding combination therapy with BB and ACEi/ARBs in reduction of TTS recurrence.

Left Ventricular Dysfunction in the Setting of Takotsubo Cardiomyopathy: A Review of Clinical Patterns and Practical Implications

Takotsubo cardiomyopathy (TTC) is primarily regarded as a form of acute and transient myocardial disease with a variety of characteristic wall-motion abnormalities. Importantly, a significant portion of TTC cases generally present with variable degrees of acute left ventricular (LV) dysfunction with or without clinical HF. On the other hand, LV dysfunction in the setting of TTC has been universally and exclusively considered as a synonym for systolic dysfunction, potentially overlooking other forms of myocardial pathologies, including transient diastolic dysfunction, in this setting. More interestingly, recent observations suggest that TTC, despite its macroscopic recovery, may not always manifest as a fully reversible phenomenon, suggesting persistence of microscopic changes at the cellular level to some degree. In clinical practice, these residual changes might largely account for the evolution of certain pathologies, including persistent diastolic dysfunction and subclinical LV dysfunction with variable symptomatology (particularly those arising during high levels of myocardial workload, including exercise, etc.) among TTC survivors. Within this context, the present review aims to highlight various clinical patterns and implications of LV dysfunction in the setting of TTC, and to provide basic information regarding morphological and mechanistic characteristics of wall-motion abnormalities in this setting.