Case Review Session 4: Non-ischemic Cardiomyopathies
3 - CMR Substrate Guided Biopsy in Cardiac Sarcoidosis – Case Report
Friday, February 14, 2020
1:35 PM – 1:45 PM
Location: Salon J1
Description of Clinical Presentation: A forty-five-year-old female patient was referred for ablation therapy of incessant polymorphic ventricular tachycardia. The patient was diagnosed with acute myocarditis after endomyocardial biopsy performed at the referring clinic. Laboratory tests showed normal CRP and near normal troponin and WBC count. Following CMR raised suspicion for cardiac sarcoidosis. However, there were no extracardiac findings associated with sarcoidosis. We opted for repeated endomyocardial biopsy. To reduce the possibility of a sampling error, a substrate guided biopsy was attempted.
Diagnostic Techniques and Their Most Important Findings: A CMR study was performed on a 1.5 Tesla (MAGNETOM Aera, Siemens Medical Imaging, Erlangen, Germany) scanner. The imaging protocol included multi-planar localizers, cine acquisitions, T1-, T2-mapping and rest perfusion scan. Approximately 15 minutes after injection of contrast agent (0.15 mmol/kg IV gadoterate meglumine (Dotarem®, Guerbet, USA), late gadolinium enhancement (LGE) data were acquired. We saw a reduced LV ejection fraction (30%) and identified several areas with focal hypokinesia, elevated myocardial T1 and T2 values and late gadolinium enhancement. Based on the LGE datasets, a 3D model of LV was generated with ADAS-3D software (Galgo Medical S.L., Barcelona, Catalonia, Spain). The procedure was performed in an EP lab to enable transseptal puncture and integration of the created 3D model to fluoroscopic images. The LV ventriculography demonstrated focal hypokinesia corresponding to the previously seen areas of inflammation. Anterior mid-ventricular segment was chosen as the optimal site for the biopsy. This could be subsequently performed without complications. Histopathological examination of the samples confirmed the suspected cardiac sarcoidosis and anti-inflammatory medication with prednisolone and methotrexate was initiated. The follow-up CMR at 3 weeks showed regredient myocardial inflammation and improved ejection fraction (45-50%) could be demonstrated on transthoracic echocardiography at 4 months from presentation. As the risk of life-threatening arrhythmia was still deemed high, an ICD was implanted.
Learning Points from this
Case: Cardiac sarcoidosis remains a challenging but important differential diagnosis to consider in cases of ventricular arrhythmia and signs of myocardial inflammation. This case illustrates the role of CMR in diagnosis of the focal myocardial involvement. Furthermore, its additive value in the planning of a substrate guided endomyocardial biopsy to reduce the possibility of sampling error is demonstrated.