Risk Factors Identified for Sudden Cardiac Death in Arrhythmic Right Ventricular Cardiomyopathy

Sustained or nonsustained ventricular tachycardia (VT) and decreased left ventricular (LV) function have been identified as risk factors for subsequent arrhythmic death in patients with arrhythmic right ventricular cardiomyopathy (ARVC), according to an analysis published in JACC: Clinical Electrophysiology.¹

Researchers sought to stratify risk of sudden death in patients with ARVC. As they explained, patients may have ventricular fibrillation that results in sudden cardiac death (SCD) as the first or early manifestation, or over the course of the disease.

“This latter feared complication is a major basis for the recommendation of ICD [implantable cardioverter defibrillator] implantation. However, there is a significant complication rate of ICDs that are implanted for many years,” they wrote. “Therefore, risk stratification to identify patients who need an ICD to prevent SCD would be useful clinical information.”

Patients (n=88; 60 males and 28 females) with definite ARVC based on the modified Task Force Criteria who did not receive ICDs were selected for risk stratification. These patients were from the Multidisciplinary Study of Right Ventricular Dysplasia, the Familial Cardiomyopathy Registry of Trieste, Italy, and a registry from the University Medical Center of Utrecht, The Netherlands.

Among these patients, there were 12 deaths during an average follow-up of 9.1 ± 7.7 years. There were no deaths among patients who did not have sustained or nonsustained VT, and 5 deaths were attributed to ventricular arrhythmias.

There was a close but nonstatistically significant relationship between index VT and all-cause mortality (P=.052), but the overall Likelihood Test was significant (P=.012). The random effect for site was small and also not significant (P=.099).

“The major finding of this study is that there is a considerable risk of death in patients with ARVC who have decreased LVEF [left ventricular ejection fraction],” the authors wrote. “Sustained or nonsustained VT was also a risk factor. From this data, it would seem reasonable to advise ICD implantation in these patients.”

They added that the results may have been skewed by the use of antiarrhythmic drugs or beta blockers and/or the selective patient population. However, in a previous study², neither sotalol nor beta blockers were associated with an increased or decreased risk of ventricular arrhythmias.

“There were no arrhythmic deaths in patients who did not have these arrhythmias [nonsustained or sustained VT],” the researchers concluded. “This information should assist in risk stratification.”

References

1. Brun F, Groeneweg JA, Gear K, et al. Risk stratification in Arrhythmic right ventricular cardiomyopathy without implantable cardioverter-defibrillators. JACC Clin Electrophysiol. 2016. doi:10.1016/j.jacep.2016.03.015.
2. Marcus GM, Glidden DV, Polonsky B, et al; for the Multidisciplinary Study of Right Ventricular Dysplasia Investigators. Efficacy of antiarrhythmic drugs in arrhythmogenic right ventricular cardiomyopathy: a report from the North American ARVC Registry. J Am Coll Cardiol. 2009;54(7):609-615. doi: 10.1016/j.jacc.2009.04.052.