Abstract 743: Severe Cardiac Sympathetic Nervous System Abnormality is Associated With Mortality in Patients With Primary Cardiac Amyloidosis and Compensated Heart Failure
Introductions: Patients with primary amyloidosis and heart failure have a poor prognosis. Limited survival is associated with autonomic dysfunction and underlying inflammatory process in patients with cardiomyopathy and heart failure.
Hypothesis: We hypothesized that sympathetic nervous system (SNS) abnormality would be associated with mortality in patients with cardiac amyloidosis and compensated heart failure. Methods: Iodine-123 metaiodoben-zylguanidine (123I-MIBG), gallium-67 citrate, and technetium-99m pyrophosphate scintigraphies were performed in 17 patients (mean ± standard deviation, age: 60±15 years, 52.9% males) with proven primary cardiac amyloidosis who had first congestive heart failure.
Results: During 2.9 ± 2.6 years follow-up, 7 patients (41.1%) had cardiac events (5 patients with cardiac deaths, and 2 patients with recurrent heart failure). The cardiac events were associated with severe SNS abnormality, defined as Heart/Mediastinum ratio <1.5 on 123I-MIBG (83.3% in 5 of 6 patients vs 18.2% in 2 of 11 patients without those, p=0.009), the diffuse cardiac uptakes of gallium-67 (80% in 4 of 5 patients vs 25% in 3 of 12 patients without those, p=0.036), but not the diffuse cardiac uptakes of pyrophosphate which reflect myocardial deposit of amyloid (60% in 3 of 5 patients vs 33.3% in 4 of 12 patients without those). After adjustment for potential confounding variables, severe SNS abnormality was an independent predictor of mortality with a hazard ratio of 17.1 [95% Confidence Interval 2 to 149, p=0.01]).
Conclusions: Severe SNS abnormality was a powerful predictor of mortality in patients with primary cardiac amyloidosis and compensated heart failure.