Renal dysfunction indicative of outcomes in hospitalized patients with takotsubo syndrome

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. 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). 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). Renal dysfunction is a simple but useful means of predicting complications in hospitalized patients with takotsubo syndrome, especially those with chronic kidney disease