*Article* **Tachycardiomyopathy in Patients without Underlying Structural Heart Disease**

**Giulia Stronati** †**, Federico Guerra \*,**†**, Alessia Urbinati, Giuseppe Ciliberti, Laura Cipolletta and Alessandro Capucci**

Cardiology and Arrhythmology Clinic, Marche Polytechnic University, University Hospital "Umberto I–Lancisi-Salesi", 60126 Ancona, Italy

**\*** Correspondence: f.guerra@staff.univpm.it; Tel.: +39-0715-965-693

† Contributed equally to the manuscript.

Received: 31 July 2019; Accepted: 5 September 2019; Published: 8 September 2019

**Abstract:** Tachycardiomyopathy (TCM) is an underestimated cause of reversible left ventricle dysfunction. The aim of this study was to identify the predictors of recurrence and incidence of major cardiovascular events in TCM patients without underlying structural heart disease (pure TCM). The prospective, observational study enrolled all consecutive pure TCM patients. The diagnosis was suspected in patients admitted for heart failure (HF) with a reduced ejection fraction and concomitant persistent arrhythmia. Pure TCM was confirmed after the clinical and echocardiographic recovery during follow-up. From 107 pure TCM patients (9% of all HF admission, the median follow-up 22.6 months), 17 recurred, 51 were hospitalized for cardiovascular reasons, two suffered from thromboembolic events and one died. The diagnosis of obstructive sleep apnoea syndrome (OSAS, hazard ratio (HR) 5.44), brain natriuretic peptide on admission (HR 1.01 for each pg/mL) and the heart rate at discharge (HR 1.05 for each bpm) were all independent predictors of TCM recurrence. The left ventricular ejection fraction at discharge (HR 0.96 for each%) and the heart rate at discharge (HR 1.02 for each bpm) resulted as independent predictors of cardiovascular-related hospitalization. Pure TCM is more common than previously thought and associated with a good long-term survival but recurrences and hospitalizations are frequent. Reversing OSAS and controlling the heart rate could prevent TCM-related complications.

**Keywords:** arrhythmias; atrial fibrillation; cardiomyopathy; heart failure; supraventricular arrhythmia; systolic dysfunction; tachycardiomyopathy; ventricular arrhythmia
