More than half of the patients with acute Puumala hantavirus infection have abnormal cardiac findings.

This study was conducted to determine the frequency, severity and outcome of cardiac findings in patients with acute Puumala hantavirus-induced nephropathia epidemica (NE). 70 consecutive, hospital-treated patients with serologically confirmed NE were prospectively examined using serial electrocardiograms (ECG), plasma troponin I, tumour necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), and echocardiography (ECHO). Examinations were repeated after 3 and 12 months. ECG changes were observed in 57% of patients. Plasma troponin I levels remained normal in all. In six patients, ECHO showed left ventricular contraction abnormalities, and 1 patient had mild pericardial effusion. There were no differences in clinical or standard laboratory findings or in plasma TNF-alpha and IL-6 concentrations between patients with and without ECG or ECHO changes. During the follow-up, all acute-phase changes in ECG and ECHO reverted to normal, which probably reflects their benign nature. We conclude that abnormal cardiac findings are surprisingly common during NE.