Clinical Electrophysiology -> SCA Risk Assessment: -> Signal Processing Techniques (SAECG/TWA, HRV, QT interval) D-PO04 - Poster Session IV (ID 15) Poster

D-PO04-229 - The Value Of A Combined Signal-Averaged ECG Score For The ARVC Diagnosis, A Study From The Nordic ARVC Registry (ID 507)


Background: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is associated with a risk for ventricular arrhythmias (VA) and sudden cardiac death (SCD). Existing diagnostic strategies are suboptimal and the value of signal-averaged electrocardiogram (SAECG) in the diagnostic work-up has been debated.
Objective: To assess the association between ventricular late potentials assessed by SAECG and (1) definite ARVC diagnosis by task force criteria, and (2) risk of VA.
Methods: Patients with clinically ascertained ARVC diagnosis or mutation-positive family members from the Nordic ARVC registry, who underwent SAECG were included (n=316, 47% females, mean age at diagnosis 39 years, n=212 with definite ARVC). Three components of SAECG, i.e. filtered QRS duration (fQRS), low amplitude signals (LAS) and root mean square amplitude of the last 40 msec (RMS40), were assessed and assigned 1 point each if fulfilling conventional definitions. SAECG score was calculated as the sum of points assigned to fQRS, LAS and RMS40 (0, 1, 2 or 3). C-statistics was used to determine the association between the SAECG score or its components and a definite ARVC diagnosis. Cox regression analyses were used to assess predictive value of SAECG components for the risk of VA, defined as documented ventricular tachycardia, appropriate ICD therapy, aborted cardiac arrest or SCD.
Results: All three SAECG components showed a similar relationship to definite ARVC diagnosis with C-statistics 0.735 (fQRS), 0.730 (LAS) and 0.735 (RMS40), all p <0.001. SAECG score showed superiority over individual SAECG components for identification of definite ARVC (C-statistics 0.767, p < 0.001). However, neither individual SAECG components nor the SAECG score were associated with the risk of VA after adjustment for age, gender, proband status and definite ARVC diagnosis.
Conclusion: In a large cohort of Scandinavian ARVC patients, we have demonstrated superiority of the combined SAECG score over individual SAECG components for diagnosis of ARVC. Prognostic value of SAECG in regard to arrhythmic risk could not be confirmed based on our data.