Clin Res Cardiol (2022). https://doi.org/10.1007/s00392-022-02087-y
Progression of QRS duration is a predictor of survival in ATTRwt amyloidosis.
S. Hein1, F. aus dem Siepen1, S. Tasche1, H. A. Katus1, N. Frey1, A. V. Kristen2
1Klinik für Innere Med. III, Kardiologie, Angiologie u. Pneumologie, Universitätsklinikum Heidelberg, Heidelberg; 2Kardiovaskuläres Zentrum Darmstadt, Darmstadt;

Introduction
Cardiac manifestation is common in transthyretin amyloidosis leading to progressive heart failure and cardiac conduction disturbances. In contrast to hereditary transthyretin (ATTRv) amyloidosis, wild type transthyretin amyloidosis (ATTRwt) occurs without any mutation in the TTR gene and affects primarily elderly males. Little is known about the natural progression of the disease.

Objectives
Therefore, our study longitudinally analyses clinical findings and patient’s signs and symptoms over a medium period of twelve months, to gain more detailed information about the clinical course of ATTRwt and potential predictors of outcome at our tertial referral center.

Methods
Clinical characteristics and diagnostic findings including ECG, echocardiography, laboratory tests and clinical functional test of 64 patients suffering from ATTRwt were collected at baseline and during a follow-up visit after 12 months.

Results
At baseline most of the patients (69.0%) already presented with dyspnea indicating clinically significant heart failure. Cardiac pacemaker was already placed in 16.9% of the patients. Moreover, the majority of the patients (67.7%) presented with abnormal ECGs, prolonged PQ (201.5±7.4ms) and QRS (119.7±4.0ms) durations as well as low voltage pattern. At one year follow up we found significant increase in QRS duration (from 119.7±4.0 to 125.9±4.3ms), intraventricular septum thickness (from 18.9±0,5mm to 19.9±0.5mm) and significantly reduced ejection fraction (EF) (from 45.4±2.1% to 38.9±2.6%) when compared to baseline visits. During the follow up period 16 patients (24.6%) died. Predictors of worse outcome were increasing QRS duration, low EF, renal dysfunction, impaired right ventricular function and need for pacemaker implantation.

Conclusions
Identification of patients at risk of mortality in ATTRwt is crucial with respect to treatment decisions. Interestingly, QRS duration appears to be a sensitive parameter for disease progression in a 12 month follow-up interval and is associated with an elevated risk for one-year mortality. These findings need to be confirmed in an independent patient cohort.
https://dgk.org/kongress_programme/ht2022/aP760.html