Arrhythmogenic Right Ventricular Cardiomyopathy
Cardiology section
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a cardiac condition that typically emerges in adulthood, affecting the myocardium, the muscular wall of the heart. It leads to the progressive breakdown of a portion of the myocardium, elevating the risk of abnormal heartbeats (arrhythmias) and sudden death. While initially asymptomatic, ARVC may manifest with sensations of
chest fluttering or pounding (palpitations), light-headedness, and fainting (syncope), particularly during strenuous physical activity. As the condition progresses, individuals may also experience shortness of breath and abnormal swelling in the legs or abdomen. In advanced stages, severe damage to the myocardium may culminate in heart failure.
ABOUT ARVC
UNDERSTANDING Arrhythmogenic Right Ventricular Cardiomyopathy
Delving Deeper into Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)
ARVC can be attributed to mutations in at least 13 genes, many of which fall under the category of desmosomal genes. These genes encode instructions for constructing components of cellular structures known as desmosomes, crucial for connecting heart muscle cells and fortifying the myocardium while facilitating signaling between adjacent cells.
Mutations in desmosomal genes compromise the functionality of desmosomes, leading to the detachment and demise of myocardial cells, especially under stress conditions such as intense physical activity. The impact is primarily observed in the myocardium surrounding the right ventricle, one of the heart's lower chambers. The damaged myocardium is gradually replaced by fat and scar tissue, causing the right ventricle walls to stretch and impede effective blood pumping. Additionally, these changes disrupt the electrical signals governing heartbeat, increasing the risk of arrhythmias. While desmosomal genes are predominant, mutations in non-desmosomal genes can also contribute to ARVC, affecting various functions such as cell signaling, providing structural stability to heart muscle cells, and maintaining a normal heart rhythm. Researchers are actively investigating the mechanisms through which mutations in non-desmosomal genes lead to ARVC.
Key genes associated with ARVC include:
PKP2 (Plakophilin-2)
DSP (Desmoplakin)
DSG2 (Desmoglein-2)
DSC2 (Desmocollin-2)
JUP (Junction Plakoglobin)
These genes play critical roles in maintaining the structural integrity of cardiac tissue, particularly in the right ventricle, and mutations in these genes can lead to the pathological changes observed in ARVC.
Genetic testing can help identify mutations associated with ARVC and guide clinical management and treatment decisions for affected individuals and their families. Early detection and intervention are essential for preventing or mitigating the serious complications associated with ARVC, including arrhythmias and sudden cardiac death.