Progression of QRS duration – a potential surrogate marker of survival in ATTRwt amyloidosis patients

In wild-type transthyretin amyloidosis (ATTRwt), the deposition of transthyretin in the myocardium leads to progressive heart failure. However, little is known about the short-term natural progression of this disease and potential predictors of outcome. Therefore, this study longitudinally analyzed the clinical findings (ECG, echocardiography, and laboratory tests) of 65 patients suffering from ATTRwt at baseline and at follow-up visits after 12 months. In total, 44 patients (67.7%) presented with abnormal ECGs, prolonged PR and QRS durations and low-voltage patterns. Pacemaker placement was performed in eleven patients (16.9%). At the one-year follow-up visit, we detected significant increases in the QRS duration (from 119.7 ± 4.0 to 125.9 ± 4.3 ms; p < 0.05), intraventricular septum thickness (from 18.9 ± 0.5 mm to 19.9 ± 0.5 mm; p < 0.05) and ejection fraction (EF) (from 45.4 ± 2.1% to 38.9 ± 2.6%; p < 0.05) compared with those at the baseline visit. During follow-up, 16 patients (24.6%) died. Predictors of worse outcomes were progression in QRS duration, low EF, reduced renal function, impaired right ventricular function and the need for pacemaker implantation. In ATTRwt, precise evaluation via routine cardiac diagnosis helps to identify patients with an elevated risk of mortality. Patients with prolonged QRS duration, progressive myocardial hypertrophy, right ventricular failure, reduced renal function and the need for cardiac pacemakers are at increased risk for one-year mortality.