Aritmojenik Sağ Ventriküler Kardiyomiyopati Hastalarında Uygun İmplantabl Kardiyoverter Defibrilatör Tedavisi için Risk Faktörleri ve Öngördürücülerinin Belirlenmesi: Tek Merkezli Deneyim
Abstract
Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is a genetic disease characterized by replacement of usually the right ventricular myocardium, but sometimes of the left ventricular myocardium, by fibrofatty tissue. This disease is significant since it can lead to sudden cardiac death (SCD), especially in the young. The most effective strategy of prevention from SCD is implantation of an implantable cardioverter defibrillator (ICD). However, ICD implantation in all ARVC patients is not meaningful. Careful stratification of patients at high risk for SCD and implantation of ICD in only these patients may be the most practical management strategy. The objective of this study is to identify ARVC patients in terms of those receiving and not receiving appropriate İCD therapy, and to define, if any, differences in demographic, clinical, electrocardiographic (SAECG), signal averaged ECG (SAECG), echocardiographic, and magnetic resosnance imaging (MRI) characteristics between the two groups. A total of 32 ARVC patients (23 males) who were being followed in the department of Cardiology of Hacettepe University, Faculty of Medicine, were included in this study. The age of the patients at diagnosis, total follow-up duration, cardiovascular risk factors and first presenting symptoms were determined. ECG, SAECG, echocardiographic and MRI features of these patients were noted. Paitents receiving and those not receiving appropriate ICD therapy were identified. During a median follow-up duration of 37 months, appropriate ICD therapy was observed in 10 of the 32 patients (31.3%). Median time from ICD implantaiton to appropriate ICD therapy was 25 months. Active smokers were significantly more likey to receive appropriate ICD therapy than non-smokers (50% vs 9.1%, p=0.019). Patients receiving appropriate ICD therapy presented with syncope more frequently than those not receiving appropriate ICD therapy (80% vs 40.9%, p=0.040). ECG features were statistically similar in the two groups. However the presence of epsilon waves and fragmented QRS complexes was more frequent in those with appropriate ICD therapy (p values of 0.013 and 0.018 respectively). Left ventricular ejection fraction (LVEF) was significantly lower in patients receiving appropriate ICD therapy (51.6±6.7% vs 61.41±7.0%, p=0.001). Besides, LV systolic dysfunction (LVEF < 50%) was more frequent in patients with appropriate ICD therapy (p=0.038). Right ventricular diameter measured from the parasternal long axis (RVD PLAX) and RVD3, measured from the the apical view was greater in patients with appropriate ICD therapy (p values of 0.017 and 0.031 respectively). RV systolic excursion velocity (RVs') obtained by tissue Doppler was significantly lower in patients associated with appropriate ICD therapy (p=0.025). Presence of late potentials as identified by SAECG did not reach statistical significance for predicting appropriate ICD discharge. Similarly, ventricular extrasystole burden as measured by Holter monitorization and VT inducibility in programmed ventricular stimulation (PVS) were both present in similar proportions in both groups. Nonsustained ventricular tacycardia (NSVT) was more frequently found in patients with appropriate ICD therapy (60% vs 22.7%, p=0.04). Among the MRI characteristics, right ventricular ejection fraction (RVEF) was significantly lower in patients with appropriate ICD therapy (31% vs 49.5%, p=0.003). Late gadolinium enhancement (LGE) was significantly more frequently present in patients with appropriate ICD therapy (60% vs 9.1%, p=0.005). Univariate analysis was significant for active smoking, presence of epsilon waves or fragmented QRS in the ECG, LVEF < 50%, presence of NSVT, LGE in MRI, and low RVEF as calculated from MRI while multivariate analysis was significant for only active smoking and the presence of LGE in MRI. In our cohort of ARVC patients, active smoking, presence of epsilon waves or fragmented QRS in the ECG, LV systolic dysfunction, presence of NSVT, LGE in MRI, and low RVEF as calculated from MRI were found to be risk factors for appropriate ICD therapy; however, only active smoking and presence of LGE in MRI were found to be useful as predictors of appropriate ICD therapy.