High-resolution three-dimensional late gadolinium-enhanced cardiac magnetic resonance imaging to identify the underlying substrate of ventricular arrhythmia

Abstract

Aims: Cardiac magnetic resonance (CMR) is recommended as a second-line method to diagnose ventricular arrhythmia (VA) substrate. We assessed the diagnostic yield of CMR including high-resolution late gadolinium-enhanced (LGE) imaging. Methods and results: Consecutive patients with sustained ventricular tachycardia (VT), non-sustained VT (NSVT), or ventricular fibrillation/aborted sudden death (VF/SCD) underwent a non-CMR diagnostic workup according to current guidelines, and CMR including LGE imaging with both a conventional breath-held and a free-breathing method enabling higher spatial resolution (HR-LGE). The diagnostic yield of CMR was compared with the non-CMR workup, including the incremental value of HR-LGE. A total of 157 patients were enrolled [age 54 ± 17 years; 75% males; 88 (56%) sustained VT, 52 (33%) NSVT, 17 (11%) VF/SCD]. Of these, 112 (71%) patients had no history of structural heart disease (SHD). All patients underwent electrocardiography and echocardiography, 72% coronary angiography, and 51% exercise testing. Pre-CMR diagnoses were 84 (54%) no SHD, 39 (25%) ischaemic cardiomyopathy (ICM), 11 (7%) non-ischaemic cardiomyopathy (NICM), 3 (2%) arrhythmogenic right ventricular cardiomyopathy (ARVC), 2 (1%) hypertrophic cardiomyopathy (HCM), and 18 (11%) other. CMR modified these diagnoses in 48 patients (31% of all and 43% of those with no SHD history). New diagnoses were 9 ICM, 28 NICM, 8 ARVC, 1 HCM, and 2 other. CMR modified therapy in 19 (12%) patients. In patients with no SHD after non-CMR tests, SHD was found in 32 of 84 (38%) patients. Eighteen of these patients showed positive HR-LGE and negative conventional LGE. Thus, HR-LGE significantly increased the CMR detection of SHD (17-38%, P < 0.001). Conclusion: CMR including HR-LGE imaging has high diagnostic value in patients with VAs. This has major prognostic and therapeutic implications, particularly in patients with negative pre-CMR workup.