Regional Variation in Technetium Pyrophosphate Uptake in Transthyretin Cardiac Amyloidosis and Impact on Mortality

• Published in: JACC. Cardiovascular imaging 2018-02, Vol.11 (2), p.234-242
• Main Authors: Sperry, Brett W., Vranian, Michael N., Tower-Rader, Albree, Hachamovitch, Rory, Hanna, Mazen, Brunken, Richard, Phelan, Dermot, Cerqueira, Manuel D., Jaber, Wael A.
• Format: Article
• Language: English
• Subjects: advanced cardiac imaging; heart failure with preserved ejection fraction; infiltrative cardiomyopathies; nuclear cardiac imaging
• ISSN: 1936-878X; 1876-7591
• DOI: 10.1016/j.jcmg.2017.06.020

This study sought to investigate the regional uptake of technetium 99m-pyrophosphate (TcPYP) in transthyretin cardiac amyloidosis (ATTR) and its association with mortality. TcPYP nuclear scintigraphy is a diagnostic and prognostic tool in ATTR. Echocardiography has identified a pattern of regional variation in longitudinal strain (LS) with a gradient of improved strain from base to apex in ATTR. Consecutive patients with ATTR were evaluated who underwent TcPYP nuclear scintigraphy with planar and attenuation corrected single-photon emission computed tomography (SPECT). Heart-to-contralateral lung (H/CL) ratio was calculated on planar images, and left ventricular (LV) uptake was determined in each of the 17 segments using SPECT. A measure of apical-sparing of myocardial TcPYP uptake, termed the apical-sparing ratio (ASR), was calculated as basal + mid / apical counts. Overall, 54 patients with ATTR (age 78 ± 9 years, 76% male, 31% hereditary ATTR) were analyzed. There was increased TcPYP uptake in basal and mid relative to apical LV segments, and an apical-sparing LS pattern on echocardiography. The right ventricle similarly showed greater uptake in basal segments. There were 26 deaths over 1.8 years median follow-up. The ASR of TcPYP uptake was associated with age-adjusted all-cause mortality (p = 0.013) with worse prognosis seen at levels