Transthyretin Cardiac Amyloidosis as Diagnosed by 99mTc-PYP Scanning in Patients with Acute Heart Failure and Preserved Ejection Fraction.

Transthyretin amyloid deposition is present in 17% of autopsies of patients with heart failure and a preserved ejection fraction (HFpEF). Technetium-pyrophosphate scintigraphy (Tc-PYP) is sensitive and specific to diagnose cardiac transthyretin amyloid deposition (ATTR). The prevalence of ATTR by Tc-PYP was evaluated along with echocardiographic parameters in patients with HFpEF. One-hundred consecutive patients with HFpEF, who had Tc-PYP, were retrospectively evaluated. Echocardiographic variables were analyzed to compare patients with positive versus negative ATTR infiltration. Myocardial ATTR was present in 19% of patients. Individuals with ATTR were older with a mean age of 82 ± 7 versus 75 ± 13 years (P = 0.03), had increased left ventricular hypertrophy with the interventricular septum measuring 1.6 (IQR, 1.4-2.0) versus 1.4 (IQR, 1.3-1.6) cm (P = 0.002), had a greater mean left ventricular mass index of 160 ± 50 g/m versus 131 ± 44 g/m (P = 0.01), and a reduced global longitudinal strain measuring -11% (IQR, -9 to -12) versus -12% (IQR, -10 to -16), P = 0.04. The prevalence of ATTR myocardial deposition demonstrated by Tc-PYP in patients with HFpEF is comparable to that of autopsy studies. It is more common in older patients, with increased left ventricular hypertrophy and reduced global longitudinal strain.