The patient was found to be hypotensive (90/60 mmHg), tachycardic (115 beats/min) and there were signs of centralisation and peripheral hypoperfusion. Thus an immediate echocardiography was performed revealing a severely impaired left ventricular systolic function with an ejection fraction of 20%.
At the Coronary Care Unit dobutamin, low dose norepinephrin and empiric piperaclillin/tazobactam were started. Hemodynamics were assessed continously and blood gas samples were taken every 2 hours.
Within 8 hours of representation her condition deteriorated, paralleled by increasing lactat values, thus an emergency-ECMO (extracorporeal membrane oxygenator) was implanted.
On the next day she had to be resusciated under ECMO perfusion due to sudden asystole. After 20 minutes of CPR (cardiopulmonary resuscitation) spontaneous circulation returned. She was stabilized with concomitant dobutamin and norepinephrine. Due to renal failure intermittennt hemodialysis was performed using the venous arm of the ECMO. Hemodynamics were monitored via radial artery and Swan Ganz catheter. On day 4 she got extubated and inotropes began to be weaned with regression of the limb ischemia. She patient was awake during these procedures. Meanwhile endotracheal aspiration after CPR returned positive for influenza B by polymerase chain reaction (PCR). Blood, BAL and urine cultures were negative for bacterial growth and empiric antimicrobials were stopped on day 5 and oseltamivir was continued for a total of 7 days. Echocardiography was performed every day, revealing a left ventricular ejection fraction of 45% on day 6. On the next day ECMO was weaned succesfully up to 1 l/min. Thus we decided to withdraw the ECMO support on the same day. The patient was discharged on hospital day 25. Transthoracic echocardiography one month after discharge demonstrated normal LV systolic function with an EF of 60%, normal LV wall thickness, trace mitral regurgitation and no ventricular dilation.
In conclusion, we report this case to draw attention that influenza B, which is usually considered less pathogenic, can unexpectedly be complicated by fulminant myocarditis or cardiomyopathy leading to cardiogenic shock in young adults. Therefore, a multidisciplinary approach including early initiation of antiviral treatment and aggressive cardiac support is essential for a favorable outcome.