Discussion
Here, we report a case of fulminant myocarditis that recovered with no neurological damage at all after 38-h asystole. To our knowledge, this is the first reported case of fulminant myocarditis that recovered from long-term asystole. Cardiac function in fulminant myocarditis is often reversible and improves after overcoming the acute phase, although patients who suffered cardiac arrest have a poor prognosis, even with ECMO or IABP. There is also no established consensus on the reversibility of myocardial function, except in specific environments, such as cardiac surgery under cardiopulmonary bypass. This case suggested that there is a possibility of subsequent improvement, even after prolonged asystole.
In fulminant myocarditis, temporary cardiopulmonary support is an important treatment approach as cardiac function can be restored following the acute phase. An observational study assessing fulminant myocarditis found that ECMO was equivalent to ventricular assist devices (VAD) and easier to introduce. Moreover, in fulminant myocarditis complicated by malignant ventricular arrhythmias, left VAD is unlikely to provide sufficient hemodynamic support when the right ventricle does not work effectively, whereas ECMO effectively bypasses biventricular failure. ECMO is the first treatment option for catastrophic myocarditis owing to low invasiveness, mobility for bedside implementation, and utility during cardiopulmonary resuscitation in cardiac arrests.
The concurrent use of devices such as VA-ECMO with IABP or Impella, rather than VA-ECMO alone, in patients with severe heart failure and cardiogenic shock may reduce the left ventricle load, minimize myocardial injury, and improve clinical outcomes. In severe cardiac dysfunction, the aortic valve does not open even when circulation is adequately secured by retrograde perfusion with VA-ECMO, and left ventricular thrombosis is a concern. The combination of IABP and V-A ECMO may reduce the risk of left ventricular thrombus by maintaining physiological antegrade blood flow 9. However, despite the theoretical advantage, the effectiveness of the combined use of IABP and V-A ECMO, is inconclusive. Several observational studies have shown conflicting results, and there are currently no randomized trials10. In this case, the risk of ventricular thrombosis was significantly high when circulation was supported by V-A ECMO only, as no antegrade blood flow was generated during asystole. Therefore, additional use of IABP might have been effective for preventing intraventricular thrombosis and reducing light ventricular load in the present case, which might result in the recovery of cardiac function. Regrettably, the current cause of fulminant myocarditis was not identified; however, this case illustrates that cardiac function might be restored even after prolonged asystole with adequate hemodynamic support.