Prevalence of Late Gadolinium Enhancement in Patients with Genetic Risk for Arrhythmogenic Cardiomyopathy

Background: Assessment of late gadolinium enhancement (LGE) during cardiac MRI (CMRI) is standard practive in the evaluation of pediatric patients with a genetic variant associated with arrhythmogenic cardiomyopathy (ACM) or a close family history of ACM. Gadolinium-enhanced imaging can contribute to the prognosis and assessment of risk in patients with ARVC, but administration adds cost, extends scan duration, and carries potential harm to patients. The primary aim of this study is to evaluate whether gadoinium-enhanced imaging provides contributive information in patients with a genetic risk for ACM with no other suggestive clinical or imaging ACM criteria.

Methods: This was a retrospective, case-control study involving pediatric patients less than 21 years old with no prior echocardiographic or electrophysiologic findings consistent with ACM who underwent screening CMRI due to a known genetic variant associated with ACM or a first-degree family member with phenotype positive, genotype negative ACM. The prevalence of LGE was calculated, along with descriptive statistics on demographic, genetic, and clinical data.

Results: Thirty-four CMRIs from 30 individuals met the initial inclusion criteria. The cohort was 56% female. Variants in the PKP gene were the most common indication for CMRI screening. Nine (26%) CMRIs identified at least one component of the revised Task Force Criteria for ACM, and two CMRIs identified abnormal ventricular morphology not otherwise specified in the Task Force Criteria. Two of the abnormal studies were positive for LGE. Of the remaining 23 normal CMRIs, none were positive for LGE.

Conclusion: Screening CMRI remains an important tool in the assessment of patients with increased genetic risk for ACM. The routine use of fadolinium in this population with an otherwise normal ventricular assessment should be questioned, particularly in patients undergoing multiple CMRIs over the course of childhood and adolescence.