Due to the severity of symptoms and extend of end-organ damage seen in this patient, we considered this a case of fulminant myocarditis (FM), characterized by an acute myocardial inflammation leading to cardiogenic shock [
10,
11,
18]. As shown in a large registry of 220 patients with histologically proven acute myocarditis, patients with FM have higher rates of cardiac death and heart transplantation compared to non-fulminant myocarditis with 28% vs. 1.8% [
18]. Stages in EM include myocardial infiltration of eosinophils causing acute necrosis, followed by hypercoagulation, potentially leading to thrombosis, either within the coronary vasculature or the ventricles in up to 13.7% [
1], which can ultimately result in permanent cardiac dysfunction due to myocardial scar formation [
18]. Clinical presentation in the often young patients [
1] can vary, including embolic cerebral infarctions [
19]. After excluding potential embolic sources, vasoconstrictive hypoxia due to high catecholamine demand and disseminated intravascular coagulation was assumed as the most likely cause for the pedal necrosis due to end-organ hypoperfusion in our patient [
20]. Moreover, thrombosis is known to complicate MCS [
21]. The underlying cause of EM in our patient remained uncertain. Pre-existing diseases in the patient`s history as Hodgkin's disease and ulcerative colitis and the recent pregnancy, however are described as possible associated conditions [
1]. Prior to the histological proof of EM, a systemic cytomegalovirus reactivation was also considered as the underlying cause [
22]. An important differential diagnosis includes drug reaction (even in absence of detectable peripheral eosinophilia) [
23,
24]. In our case, specific information on the timings of any medication use prior to hospitalisation was positive for mesalazine only. Features that point against eosinophilic granulomatosis with polyangiitis as the diagnosis were missing specifities as asthma and blood eosinophilia and ear, nose and throat involvement, although it is known that ANCA is only positive in a proportion of eosinophilic granulomatosis patients [
25]. Cardiac MRI showing no significant fibrosis suggests an acute aetiology. Peripheral eosinophilia, as in our case, is absent in up to 25% of patients with EM [
1] and underscores the importance of endomyocardial biopsy in cases of unexplained abrupt LV impairment [
26,
27]. Immunosuppression is the most common treatment modality for EM [
1], although no clinical trial has tested its efficacy. Remarkable is the observation that the patient started to improve prior to initiation of immunosuppression with a rapid restitution of the biventricular function. Thus, considering also the positivity for cytomegalovirus, the initiated steroid therapy was probably not necessary in our case. The extent of profound cardiac- and multiorgan dysfunction in our patient required immediate MCS allowing time to initiate positive inotropic pharmacotherapy, recommended for the management of patients with acute heart failure to help myocardial recovery and for making the proper diagnosis [
12,
13]. For patients in FM, ECLS via VA-ECMO is the most commonly described MCS [
9,
11,
15]. However, it should be taken into account that VA-ECMO increases LV afterload severely, resulting in LV distention and pulmonary edema. The Impella® device provides circulatory support with LV-venting, reduces LV-afterload [
10] and has been described as sole therapy in rare cases of acute FM [
28,
29]. However, in patients with concomitant right ventricular dysfunction, the Impella is ineffective and can be even counterproductive by exposing the patient to the adverse effects of such support (anemia, complications related to vascular access, distal limb ischemia, infections) [
21]. In this specific clinical context, VA-ECMO may be considered as first MCS alternative and, eventually, Impella as LV venting device. In our patient, due to the rapidly developing also right ventricular dysfunction, the Impella® device could not provide adequate hemodynamic support. The MCS strategy was therefore escalated to the ECMELLA concept as the next reasonable step. After additional implantation of a VA-ECMO, the hemodynamic situation gradually stabilized. Continued circulatory support with LV-venting and inodilatative therapy allowed quick recovery of LV function.
Even in fulminant cardiogenic shock due to EM and consecutive biventricular heart failure with multi-organ dysfunction, the ECMELLA concept can be an effective way of MCS therapy providing the time frame for decision making processes, initiation of specific therapy in terms of inotropic and immunosuppression support and to allow cardiac reconstitution. This adds to current evidence, however further research is needed to verify the ECMELLA concept in a wider clinical use.