Myocarditis is an acquired cardiomyopathy related to acute or chronic inflammation of the myocardium either focal or diffuse. In Europe and North America viral infections constitute the most frequent causative agent of acute myocarditis, including among others Coxsackie virus B3, Epstein-Barr virus, human herpes virus 6 and Cytomegalovirus. Cardiovascular magnetic resonance (CMR) represents an important diagnostic tool by revealing in many cases late gadolinium enhancement (LGE) areas, mostly involving the subepicardium, often extending to mesocardium. The present study is focusing on the presence of LGE...

48 consecutive patients included in this prospective study (44 men, 4 women, median age 29 years) with suspected acute myocarditis. All patients reported a history of previous viral infection within the last 15-25 days, 41 had an upper respiratory tract infection while the remaining 7 had symptoms related to viral gastroenteritis. About 5 to 10 days before CMR examination 42 out of 48 presented episodes of chest pain and discomfort and 44 had elevated cardiac troponin blood levels. ECG-gated CMR imaging was performed in a...

Five out of 48 patients (10%) showed a severely decreased LVEF and underwent endomyocardial biopsy. All were diagnosed with acute myocarditis by immunohistology. Viral genomes regarding Coxsackie virus were detected in 2 patients, Parvovirus B19 in 1, Ebstein-Barr virus in one patient and Cytomegalovirus in other one patient. In 23 cases (48%) were basal inferior and basal inferolateral segments were simultaneously involved, specific serum antibodies for PVB19 were detected (Figure 1). In three patients (6%) with more extended LGE areas, apart from lateral wall segments,...

A predilection for LV basal inferior and basal inferolateral segments seems to exist in myocarditis infection by PVB19, while HHV6 infection seems to involve more septal and anteroseptal segments of LV, especially in heavy smokers. In a few cases, acute myocarditis caused by CMV, Cocksackie, Ebstein-Barr or even PVB19, was linked to a severely decreased LVEF.

Efstathios E. Detorakis, MD, PhD Consultant radiologist Affidea Heraklion Crete Greece [email protected]

Mahrholdt H et al. Presentation, patterns of myocardial damage, and clinical course of viral myocarditis. Circulation. 2006 Oct 10;114(15):1581-90. Epub 2006 Oct 2.