Cardiovascular magnetic resonance imaging and endomyocardial biopsy in giant cell myocarditis: a case report on diagnostic challenges and future perspectives

Abstract

Background: Giant cell myocarditis (GCM) is a rare but often fast-progressing cardiac disease with a high risk of poor outcome. Nonetheless, its differentiation from other diseases like cardiac sarcoidosis (CS) using cardiovascular magnetic resonance imaging (CMR) remains challenging.

Case summary: A 27-year-old male patient presented to the emergency department with acute cardiac decompensation and severely reduced left ventricular ejection fraction. After exclusion of an ischaemic cause of heart failure, CMR was performed, showing signs of acute inflammation and late gadolinium enhancement patterns that were indistinguishable between GCM and CS. Despite the suspicion of sarcoidosis based on a lymph node biopsy, endomyocardial biopsy (EMB) provided clear evidence of typical histopathological changes consistent with GCM. An immunosuppressive therapy was initiated leading to an improvement in left ventricular function.

Discussion: Cardiovascular magnetic resonance imaging is an important cornerstone in the diagnostic pathway of GCM, however, only complementary use with EMB allows reliable diagnosis. Therefore, full diagnostic and especially prognostic potential of CMR remains unclear but offers an important starting point for optimizing patient management.

Keywords: Cardiovascular magnetic resonance; Case report; Histopathology; Multimodal imaging; Myocarditis; Sarcoidosis.

Figure 1

Initial cardiac magnetic resonance imaging. Cardiac magnetic resonance imaging showed ubiquitously increased T1 (A: T1 native: 1489 ms; ECV: 41.2%) and T2 values (B: 50 ms). Furthermore, multifocal late gadolinium enhancement (C, D: arrows) including the septal and lateral region as well as the anterior insertion point, extending into the right ventricular wall (D: ‘hook sign’), was seen in phase-sensitive inversion recovery imaging. HS, hook sign; LA, left atrium; LV, left ventricle; PE, pericardial effusion; PLE, pleural effusion; RA, right atrium; RV, right ventricle.

Figure 2

Pulmonary lymph nodes and biopsy results. Cardiovascular magnetic resonance imaging revealed bilateral hilar lymphadenopathy (A, asterisk). A lymph node biopsy revealed non-necrotizing granulomas (B) containing multinucleate giant cells (C), as typically seen in sarcoidosis. Histological images were kindly provided by the Institute of Pathology, University Medical Center of Goettingen, Germany.

Figure 3

Right ventricular endomyocardial biopsy. Endomyocardial biopsy showed diffuse fibrosis and severe inflammation (A: blue areas; Masson trichrome). The presence of giant cells (B: asterisk) and increased amounts of eosinophilic granulocytes (B: arrows; Giemsa) was indicative of a diagnosis of giant cell myocarditis. Histological images were kindly provided by the Institute for Pathology and Neuropathology, University Hospital Tuebingen, Germany.

Figure 4

Cardiac magnetic resonance imaging eight months after symptom onset. The eight-month follow-up cardiac magnetic resonance imaging showed persistent but overall reduced late gadolinium enhancement (arrows) in phase-sensitive inversion recovery imaging. HS, hook sign; LA, left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle.