Comparison of Right Ventricular Longitudinal Strain Imaging, Tricuspid Annular Plane Systolic Excursion, and Cardiac Biomarkers for Early Diagnosis of Cardiac Involvement and Risk Stratification in AL Amyloidosis: a Five Year Cohort Study

Abstract

Objectives: The aim was to determine the role of assessing right ventricular (RV) function, using standard echocardiography and Doppler myocardial imaging (DMI), in the early diagnosis of cardiac amyloidosis (CA) and in prediction of mortality. Methods: A total of 249 patients with AL amyloidosis were categorized on the basis of left ventricular thickness and E' velocity, and compared to 38 age- and sex-matched controls. Standard echocardiographic parameters of RV function were assessed, and longitudinal systolic myocardial velocity, strain rate (sSR), and strain (sS) were determined for the basal and middle RV free wall segments. Patients were followed for the endpoint of mortality. Results: RV tricuspid annular plane systolic excursion (TAPSE), and all DMI measurements were lower in AL-normal-echo group than in controls. A bivariate model including strain of the basal segment of the RV free wall and TAPSE was the best for distinguishing AL-normal-echo patients from controls (ROC area: 0.81, positive predictive value, 75%; negative predictive value, 64%). During a median follow-up of 53 months, 126 patients died (51%). Male gender (HR 2.2 P 0.005, (log) BNP levels (HR 1.4 P 0.003), Troponin T levels (HR 1.6 P 0.01), pleural effusion (HR 3.6 p < 0.0001), E/A ratio (HR 1.3 P 0.006), RV systolic pressure (HR 1.02 P 0.01), and RV sSR of the middle segment (HR 1.3 P 0.02) were the most significant independent predictors of death. Conclusions: DMI measures of RV are useful to identify early impairment of cardiac function or to stratify risk of death in patients with AL amyloidosis. Further studies with longer follow-up are warranted to confirm these results.