Evolution and prognostic value of left ventricular deformation and myocardial work parameters in transthyretin amyloid cardiomyopathy

Abstract

Aims: Wild-type transthyretin amyloid cardiomyopathy (ATTR-CM) is an increasingly recognized condition. It remains challenging to estimate the extent of disease and the prognosis for most patients. Myocardial work is a sensitive echocardiographic approach that improves the characterization of myocardial damage. We investigate the parameters of myocardial deformation and work in ATTR-CM patients and their changes over time.

Methods and results: We analysed clinical, electrocardiographic, biological, and echocardiographic characteristics in 113 patients [median age 82 (77-85), 90.4% male] diagnosed with wild-type ATTR-CM based on international consensus at a single centre. We compared the data at baseline and 18-month follow-up. Thirty-four patients died and 12 were hospitalized for heart failure at a median follow-up of 935 days (interquartile range 691-1159 days). Left ventricular end-diastolic diameter, left atrial strain during reservoir phase (LASRES), left ventricular longitudinal strain, global work index (GWI), global constructive work significantly decreased from baseline to 18 months, while left ventricular wall thickness increased. Left ventricular ejection fraction, right ventricular free wall strain (FWS), global wasted work (GWW), and global work efficiency did not alter significantly. Strain parameters were identified as prognostic on baseline evaluation using a multivariate analysis: GWI, GWW, FWS, and LASRES. They were significantly associated with the risk of death and hospitalization for heart failure.

Conclusion: Multi-chamber strain assessment may improve the surveillance of patients with ATTR-CM, and myocardial work parameters may improve clinical risk stratification in this population.

Keywords: amyloid cardiomyopathy; global longitudinal strain; global wasted work; wild-type transthyretin.