Background Vaccination against SARS-CoV-2 has been the main tool to contain the pandemic. The rush development of the 3 vaccines and their expedited approval have led to inoculation of millions of patients around the world, leading to a containment of the disease. Despite continuous viral mutations and the identification of weaker variants, the severity of the infections has been mild, with many patients being either asymptomatic or recovering at home. Currently the focus has shifted from the host of organ damage related to the infection to potential side effects of the vaccine. Myocarditis has been reported as one of the potential side effects from the mRNA vaccine, affecting young healthy individuals. Up to September 30, 2021, 1.243 cases of myocarditis after vaccination with BNT162b2 Comirnaty© were registered in young adults by the Paul-Ehrlich-Institute in Germany alone. The exact pathophysiology and the risk factors for myocarditis following vaccination remain unclear. We present a case series of eight patients with cardiac symptom shortly after SARS-CoV-2 mRNA vaccination (BNT162b6, Biontech, Comirnaty© or mRNA-1237 Moderna, Spikevax©). Patients and methods Eight patients between 13 and 56 years of age, vaccinated with either BNT162b2 or mRNA-1273 mRNA vaccine between January and August 2021 developed cardiac side effects shortly after either their first or second dose of the vaccine. Clinical data were retrieved from the clinical information system and analyzed. To support diagnosis of myocarditis or pericarditis, cardiac magnetic resonance imaging (MRI) was performed shortly after the onset of symptoms, with further investigations in severe cases. Symptoms were defined as dyspnea, chest pain and cardiac arrhythmia as determined by electrocardiography. Results Eight patients (5 males and 3 females) developed cardiac symptoms compatible with myocarditis, according to the CDC criteria, shortly after SARS-CoV-2 mRNA vaccination. Three patients (2 males, 1 female) required hospitalization due to severe chest pain and elevated troponin levels. All patients recovered fully within 7 days from the symptom onset. Conclusions Our data suggest that cardiac adverse events such as myocarditis or pericarditis shortly after SARS-CoV-2 mRNA vaccination are rare but possible and occur particularly in male patients.

Acute kidney injury (AKI) is a common complication post-PCI. Here, in a single-center observational registry, we compared the frequency of AKI in patients at elevated risk for AKI (based on Mehran risk stratification scoring) who underwent VA-ECMO- or Impella-supported high-risk PCI. A total of 28 patients scheduled for elective high-risk PCI with mechanical circulatory support were studied prospectively. All patients were turned down for surgery due to exceedingly high risk. Allocation to VA-ECMO (n=11) or Impella (n=17) was performed according to site-specific restrictions on the daily availability of the VA-ECMO platform as a prospective enrollment and performed prior to initiation of PCI. We analyzed AKI incidence as our primary endpoint, as well as PCI success, duration, and peripheral complications. All patients were successfully revascularized and had MCS weaned at the end of the procedure. Baseline GFR and procedural contrast media were similar. Despite similar risks for AKI as calculated by the Mehran score (35 ± 18.9 vs. 31 ± 16.6 %; p=0.55), patients supported by Impella during PCI demonstrated a reduced incidence of AKI (55 vs. 12 %; p=0.03). MCS-assisted high-risk PCI with VA-ECMO or Impella is feasible. However, Impella is associated with a shorter procedure time and a lower incidence of AKI.