Independent Predictors of Survival in Primary Systemic (AL) Amyloidosis, Including Cardiac Biomarkers and Left Ventricular Strain Imaging: An Observational Cohort Study

Background

The prognostic value of Doppler myocardial imaging, including myocardial velocity imaging, strain, and strain rate imaging, in patients with primary (AL) amyloidosis is uncertain. The aim of this longitudinal study was to identify independent predictors of survival, comparing clinical data, hematologic and cardiac biomarkers, and standard echocardiographic and Doppler myocardial imaging measures in a cohort of patients with AL amyloidosis.

Methods

A total of 249 consecutive patients with AL amyloidosis were prospectively enrolled. The primary end point was all-cause mortality, and during a median follow-up period of 18 months, 75 patients (30%) died. Clinical and electrocardiographic data, biomarkers (brain natriuretic peptide and cardiac troponin T) and standard echocardiographic and longitudinal systolic and diastolic Doppler myocardial imaging measurements for 16 left ventricular segments were tested as potential independent predictors of survival.

Results

Age (hazard ratio [HR], 1.03; P = .03), New York Heart Association class III or IV (HR, 2.47; P = .01), the presence of pleural effusion (HR, 1.79; P = .08), brain natriuretic peptide level (HR, 1.29; P = .01), ejection time (HR, 0.99; P = .13), and peak longitudinal systolic strain of the basal anteroseptal segment (HR, 1.05; P = .02) were independent predictors in the final model.

Conclusions

Multivariate survival analysis identified independent predictors of clinical outcome in patients with AL amyloidosis: New York Heart Association class III or IV, presence of pleural effusion, brain natriuretic peptide level > 493 pg/mL, ejection time < 273 ms, and peak longitudinal systolic basal anteroseptal strain less negative than or equal to −7.5% defined a high-risk group of patients.

Keywords: AL amyloidosis, Restrictive cardiomyopathy, Echocardiography, Doppler myocardial imaging, Strain rate imaging

Abbreviations: BNP, Brain natriuretic peptide, CI, Confidence interval, DMI, Doppler myocardial imaging, dMV, Diastolic myocardial velocity, dMV-A, Late diastolic myocardial velocity, dMV-E, Early diastolic myocardial velocity, dSR-A, Late diastolic strain rate, dSR-E, Early diastolic strain rate, HR, Hazard ratio, ICC, Intraclass correlation coefficients, LV, Left ventricular, NT-proBNP, N-terminal pro-BNP, NYHA, New York Heart Association, PBSCT, Peripheral blood stem cell transplantation, sMV, Systolic myocardial velocity, sS, Systolic strain, sSr, Systolic strain rate, 2D, Two-dimensional