Diagnostic characteristics of acute myocarditis

Abstract

Background: Acute myocarditis is an inflammation of the heart muscle. Its unpredictable evolution justifies the importance of its early recognition. The clinical polymorphism associated with the lack of sensitivity of conventional diagnostic means make diagnosis a challenge for the clinician. However, the magnetic resonance imaging has been of great interest for the differential diagnosis as well as for the evolutionary follow-up of this pathology.
Aim:Determine the clinical profile of acute myocarditis and the contribution of multimodal imaging in its diagnosis
Methods: This was a descriptive, retrospective study, including 31 patients hospitalized for acute myocarditis at the cardiology department of the Internal Security Forces Hospital-La Marsa between 2011 and 2017.
Results: The mean age of our patients was 36.5 ± 13.3 years [17-63] with a clear male predominance (sex ratio = 6.75). Smoking was the most common cardiovascular risk factor (60%). Fifty percent of the population had only two cardiovascular risk factors. The most common clinical picture was acute chest pain (84%) preceded by influenza-like illness (53%). The electrocardiogram was pathological in 97% of cases. Hyperleukocytosis was objectified in 33% of cases. Elevation of C-reactive protein was present in 80% of cases. As for troponins, they were high in 94% of cases. Overall myocardial contractility was conserved in 84% of cases with segmental kinetic disorders in 45%. Cardiac magnetic resonance imaging showed pericardial effusion (10%), spontaneous myocardial hypersignal in triple-reversal-T2 recovery (42%) and which corresponded to the zones of late enhancement. Late contrast enhancement was predominant at the lateral wall (39%), with epicardial involvement occurring in 100% of cases.28 patients had a favorable outcome after a follow-up of 24 months. However, there was only one case of death at 3 months and two cases that progressed to dilated cardiomyopathy.
Conclusion: Acute myocarditis is mainly a disease of the young male subject. Cardiac magnetic resonance imaging is of crucial interest for positive diagnosis.