Predictor of Cardiovascular Events in Patients with Mutant Transthyretin Amyloidosis

Background: It is well known mutant transthyretin (mt-ATTR) amyloidosis often cause cardiac amyloidosis and cardiac involvements worsen clinical outcome. However, there is little information about predictor of cardiovascular outcome in mt-ATTR patients with long-term follow up in Japan. We analyzed the incidence poor outcome and identified the predictive factors in noninvasive risk stratification in Japanese patients with mt-ATTR. Method and Result: We evaluated 81 consecutive mt-ATTR patients (56.7 ± 13.7 years old). We evaluated all cause mortality and incidence of cardiovascular event. During median follow up of 7.0 years, 21 patients (25.9%) had adverse events; all cause death (n = 8), cardiac event including hospitalization due to worsening heart failure (n = 2), CRTD implantation (n = 2), ICD implantation due to ventricular tachycardia (n = 5), and pacemaker implantation due to symptomatic bradyarrhythmia (n = 5). Univaluate cox regression analysis revealed that genetic mutation (nonVal30Met), duration of mt-ATTR, IVSTd, EF, E/e, QRS width, creatinine and Ln(cardiac troponin T) levels were predictors for poor prognosis. In multivaluate cox regression analysis, IVSTd and nonVal30Met mutation were significantly and independently correlation with poor prognosis [IVSTd; hazard ratio : 1.168, 95%CI : 1.036 - 1.317; P = .01, nonVal30Met mutation; HR: 8.779, 95%CI:3.105 - 24.822; P < .01]. Conclusion: Genetic mutation and IVSTd were useful predictors of cardiovascular events. These results revealed it is important to evaluate cardiac involvement, especially nonVal30Met mt-ATTR patients.