Etiology is a third major cause--in addition to type of organ-involved (soft-tissue/heart) and tracer type--of scintigraphic variability in cardiac amyloidosis. This is a highly relevant consideration for future studies. We conclude that 99mTc-DPD scintigraphy is a useful step in the workup of the differential diagnosis of TTR versus AL etiology in patients with documented cardiac amyloidosis.

AimsThere is no cure for pulmonary arterial hypertension, but current approved treatment options include prostanoids, endothelin-receptor antagonists, and phosphodiesterase type-5 inhibitors. The effect on survival of these compounds has not been appropriately assessed in individual trials because of small sample size and short duration. We performed a meta-analysis of all randomized controlled trials with drugs published in this condition.Methods and resultsTrials were searched in the Medline database from January 1990 to October 2008. The primary analysis included only studies with a placebo comparator arm, the sensitivity analysis also included studies comparing two active treatment arms. The main outcome measure was all-cause mortality. Twenty-one trials were included in the primary analysis (3140 patients) and two additional studies (59 patients) were included in the sensitivity analysis. Average duration of the trials was 14.3 weeks. All-cause mortality rate in the control group was 3.8%. Active treatments were associated with a reduction in mortality of 43% (RR 0.57; 95% CI 0.35–0.92; P = 0.023); the sensitivity analysis confirmed a reduction in mortality of 38% (RR 0.62; 95% CI 0.39–1.00; P = 0.048).ConclusionThe results of this meta-analysis suggest an improvement of survival in the patients treated with the targeted therapies approved for pulmonary arterial hypertension.

Background— Most studies of amyloidotic cardiomyopathy consider as a single entity the 3 main systemic cardiac amyloidoses: acquired monoclonal immunoglobulin light-chain (AL); hereditary, mutated transthyretin-related (ATTRm); and wild-type transthyretin-related (ATTRwt). In this study, we compared the diagnostic/clinical profiles of these 3 types of systemic cardiac amyloidosis. Methods and Results— We conducted a longitudinal study of 233 patients with clear-cut diagnosis by type of cardiac amyloidosis (AL, n=157; ATTRm, n=61; ATTRwt, n=15) at 2 large Italian centers providing coordinated amyloidosis diagnosis/management facilities since 1990. Average age at diagnosis was higher in AL than in ATTRm patients; all ATTRwt patients except 1 were elderly men. At diagnosis, mean left ventricular wall thickness was higher in ATTRwt than in ATTRm and AL. Left ventricular ejection fraction was moderately depressed in ATTRwt but not in AL or ATTRm. ATTRm patients less often displayed low QRS voltage (25% versus 60% in AL; P <0.0001) or low voltage-to-mass ratio (1.1±0.5 versus 0.9±0.5; P <0.0001). AL patients appeared to have greater hemodynamic impairment. On multivariate analysis, ATTRm was a strongly favorable predictor of survival, and ATTRwt predicted freedom from major cardiac events. Conclusions— AL, ATTRm, and ATTRwt should be considered 3 different cardiac diseases, probably characterized by different pathophysiological substrates and courses. Awareness of the diversity underlying the cardiac amyloidosis label is important on several levels, ranging from disease classification to diagnosis and clinical management.