The goal of this study is to describe the natural history and clinical events for patients who have Arrhythmogenic Cardiomyopathy with Pathogenic Plakophilin-2 Variants (PKP2-ACM) managed with standard of care.

This is an observational study with both retrospective and prospective data collection. The study is designed to describe the natural history of PKP2-ACM including the signs and symptoms, key clinical events, and impact of the disease on quality of life. A hybrid (retrospective and prospective data collection) approach is being taken with the aim of achieving robust and longitudinal data generation.

Inclusion Criteria

Patients must meet all the following criteria (and none of the exclusion criteria) to be eligible for study participation:

1. Male or female age 12 years or older at the time of providing informed consent (i.e., ICF provision).
2. Capable and willing to provide signed informed consent and/or assent, which includes compliance with the requirements and restrictions listed in the ICF and protocol.
3. Clinical diagnosis of arrhythmogenic cardio myopathy (ACM)
4. Documentation of a pathogenic or likely pathogenic variant in PKP2 by a CLIA-certified genetic testing laboratory
5. History of ICD implantation ≥6 months prior to ICF provision
6. Left ventricular ejection fraction by echocardiogram or cardiac magnetic resonance (CMR) ≥50% at ≤12 months prior to ICF provision

Exclusion Criteria

Patients meeting any of the following criteria are excluded from study participation:

1. Gene testing indicates that the subject's arrhythmia or cardiomyopathy may be related to a genetic etiology other than PKP2 truncating variant.
2. Concurrent participation in any other clinical investigation involving use of an investigational agent that could confound results of this study.
3. Previous participation in a study of gene transfer or gene editing.
4. NYHA Class IV heart failure.
5. Presence or requirement for mechanical circulatory support (MCS) or predicted need for MCS or heart transplantation within 6 months of enrollment.
6. Prior cardiac or other organ (lung, liver, other) transplantation.
7. Pacemaker dependent rhythm documented, as assessed by the principal investigator ≤12 months prior to enrollment.
8. Positive human immunodeficiency virus (HIV) antibody test.
9. Unwillingness to comply with study procedures, including follow-up as specified by this protocol, or unwillingness to fully cooperate with the investigator.

Patients 12 years of age and over with confirmed PKP2-ACM.