Myocarditis is an inflammatory disease of cardiac muscle caused by a variety of etiologies, myocardial involvement and clinical presentations ranging from chest pain to extreme conditions such as cardiogenic shock or death. The variability in presentation reflects the variability in histological disease severity, etiology, and disease stage at presentation. The diagnosis may be suspected by clinical and noninvasive features and is confirmed by endomyocardial biopsy by established histologic, immunologic, and immunohistochemical criteria. CMR imaging is a valid diagnostic support which can detect important myocarditis features from evidence of inflammatory hyperemia and edema to myocardial scar. Due to its clinical presentation and the absence of a safe sensitive non-invasive diagnostic tool, the frequency of this condition and its specific etiology is often difficult to identify, and because of this, the cause is frequently unknown. Anyway among the infectious etiologies, viruses are the presumed to be the most frequent pathogens.
We analyzed the main clinical features of patients who were hospitalized for myocarditis in our province in the past five years.
Since 2018, 53 patients received a diagnosis of myocarditis. Mean age was 38, 40 (75%) of them were males. The vast majority of patients underwent CMR as a part of diagnostic work-up and we found lateral wall as the most frequently involved. Almost half of the patients showed oedema as a sign of acute inflammation and 35% had more than one segment affected. Mean ejection fraction was 60%. 22 of them were discharged as having as “idiopathic”, 18 had a viral cause (of which 2 were clearly COVID-related) with gastroenteritis being the most common clinical presentation. Of note, only one case was associated with COVID-19 vaccination.
Figure 1 shows different distribution of the cases per year. Of note, we did not observe an increased incidence in the last 3 years and mean age was similar in the years analysed possibly reflecting a limited effect of COVID and COVID-vaccination related incidence in our population.