Setti, Martina

Abstract Aims Dilated cardiomyopathy (DCM) with arrhythmic phenotype combines phenotypical aspects of DCM and predisposition to ventricular arrhythmias, typical of arrhythmogenic cardiomyopathy. The definition of DCM with arrhythmic phenotype is not universally accepted, leading to uncertainty in the identification of high-risk patients. This study aimed to assess the prognostic impact of arrhythmic phenotype in risk stratification and the correlation of arrhythmic markers with high-risk arrhythmogenic gene variants in DCM patients. Methods and results In this multicentre study, DCM patients with available genetic testing were analysed. The following arrhythmic markers, present at baseline or within 1 year of enrolment, were tested: unexplained syncope, rapid non-sustained ventricular tachycardia (NSVT), ≥1000 premature ventricular contractions/24 h or ≥50 ventricular couplets/24 h. LMNA, FLNC, RBM20, and desmosomal pathogenic or likely pathogenic gene variants were considered high-risk arrhythmogenic genes. The study endpoint was a composite of sudden cardiac death and major ventricular arrhythmias (SCD/MVA). We studied 742 DCM patients (45 ± 14 years, 34% female, 410 [55%] with left ventricular ejection fraction [LVEF] <35%). During a median follow-up of 6 years (interquartile range 1.6–12.1), unexplained syncope and NSVT were the only arrhythmic markers associated with SCD/MVA, and the combination of the two markers carried a significant additive risk of SCD/MVA, incremental to LVEF and New York Heart Association class. The probability of identifying an arrhythmogenic genotype rose from 8% to 30% if both early syncope and NSVT were present. Conclusion In DCM patients, the combination of early detected NSVT and unexplained syncope increases the risk of life-threatening arrhythmic outcomes and can aid the identification of carriers of malignant arrhythmogenic genotypes.

The need for multiple transducer positions, especially from right parasternal windows, is consistently mentioned in the recommendations for the accurate measurement of peak velocities across a stenotic aortic valve, but yet poorly adopted. We performed a subanalysis of the largest prospective series on the right parasternal acoustic windows in patients with aortic stenosis (330 consecutive) to calculate the degree of misalignment and estimate the potential outcome implication of this often-forgotten approach. The right parasternal view was highly feasible with an average estimated misalignment from the apical view of 14 ± 16 degree; in 10 cases, an estimated misalignment >40 degree. Right parasternal assessment (vs. apical alone) provided a significant reclassification from moderate to severe or even very-severe aortic valve stenosis. Considering a wellestablished survival benefit provided by either percutaneous or surgical valve replacement in patients with severe aortic stenosis the reclassification would result in approximately 1 life-year saved for every 30–35 patients in whom parasternal view were effectively utilized.