Renal dysfunction indicative of outcomes in hospitalized patients with takotsubo syndrome

Abstract

Background: Left ventricular dysfunction as part of takotsubo syndrome is reversible, and the long-term prognosis appears favorable. However, life-threatening complications are not uncommon during the acute phase, and it remains unclear whether renal dysfunction is a factor in complications suffered by hospitalized patients with takotsubo syndrome. The present study was conducted to investigate the implications of renal dysfunction in this setting. Methods: Data from 61 consecutive patients (male, 21; female, 40) diagnosed with takotsubo syndrome at our hospital between years 2010 and 2016 were evaluated retrospectively. In-hospital complications by definition were all-cause deaths and severe pump failure (Killip class ≥III). Results: Overall, 30 patients (49%) developed renal dysfunction. In the 32 patients (52%) who suffered in-hospital complications (mortality, 10; severe pump failure, 22), estimated glomerular filtration rate (eGFR) was significantly lower by comparison (51.3±29.8 vs. 69.5±29.0; p=0.019). Low eGFR (<30 ml/min per 1.73m2) proved independently predictive of in-hospital complications (hazard ratio =2.84, 95% confidence interval: 1.20–6.69) in multivariate Cox hazard analysis, also showing a significant association with peak event rate of Kaplan–Meier curve (log-rank test, p=0.0073). Similarly, patients with chronic kidney disease were at significantly greater risk of in-hospital complications (hazard ratio=2.49, 95% confidence interval: 1.01–5.98), relative to non-compromised counterparts (eGFR >60 ml/min per 1.73m2). Conclusion: Renal dysfunction is a simple but useful means of predicting complications in hospitalized patients with takotsubo syndrome, especially those with chronic kidney disease.