Arrhythmogenic Cardiomyopathies (AVC)
Arrhythmogenic ventricular cardiomyopathy (AVC) is rare condition that affects the heart muscle and can be associated with ventricular arrhythmias. Other names that are used interchangeably are arrhythmogenic right ventricular cardiomyopathy (ARVC), or arrhythmogenic right ventricular dysplasia (ARVD).
This condition affects the protein layers that connect the heart muscle at a microscopic level are replaced with fat and scar, impairing its ability to squeeze and relax with each heartbeat. AVC affects 1 in 2,500 individuals, gender is equally affected and commonly diagnosed in age groups of 20-40 years old, however symptoms have been seen in all ages. The causes may be a part of other conditions that can affect the heart muscle, however more commonly it is from a cardiac genetic abnormality that alters the proteins and ions within the cells. In patients with known AVC, about 40-50% of the time a cardiac genetic mutation can be identified. This is an autosomal dominant disease, this means that if you have AVC, there is a 50% risk of passing the disease to your offspring.
Signs and Symptoms
Patients with AVC may present clinically with symptoms (see below) atrial fibrillation, abnormal electrical system, ventricular arrhythmias, or sudden cardiac arrest.
Patients may be asymptomatic and the finding of decreased function or ventricular scar could be identified incidentally during cardiac screening if performed secondary to a significant family history of the disease.
Other common reported symptoms are
- chest pain
- heart racing
- shortness of breath
- decrease energy
The presence of any of these symptoms should be discussed with a cardiologist/electrophysiologist team.
The diagnosis of ACM is made through a series of noninvasive tests, none of which are highly specific or sensitive. The diagnosis is made based on specific diagnostic criteria.
ARVC should be considered in patients who have syncope during exercise, exercise induced arrhythmias, survivors of cardiac arrest (particularly during exertion), frequent premature ventricular contractions (PVC’s, > 500 in 24 hours), all symptoms of above in the absence of other heart disease.
Your cardiologist may consider the following tests to help with the diagnosis:
- Signal Average ECG
- Echocardiogram (or echo)
- Cardiac MRI
- Exercise Stress Test
- Holter monitor
- Event monitor
- Implantable loop recorder
- Genetic testing
Management depends on the severity of the disease and symptoms. Medications may be used to manage the function of the heart and the arrhythmias, commonly beta blockers or amiodarone. For patients who are identified to be high risk for sudden cardiac arrest, an (ICD) implantable cardio defibrillator may be necessary. Your cardiologist/electrophysiologist may recommend that you undergo electrophysiology study (EPS) with or without an ablation. A cardiac ablation is a procedure that may be recommended in attempt to provide a potential cure or minimize the frequency of an arrhythmia. Heart transplantation is rare, but may be considered if standard medical treatment does not manage your symptoms and progressive heart failure is acquired.
Avoidance of competitive strenuous sports is often recommended. All activities should first be discussed with your cardiologist and/or electrophysiologist prior to participating.