Abstract High-dose melphalan (HDM) plus stem cell transplantation is an effective treatment for light-chain amyloidosis (AL), but is associated with high treatment-related mortality in patients with cardiac involvement. We studied 187 patients with cardiac involvement with AL who underwent HDM between 1996 and 2008. The median age was 57 years and the median time from diagnosis to HDM was 3.6 months. Half of the patients received reduced-dose melphalan (100-160 mg/m2). The median overall survival (OS) was 66 months, 54 months from diagnosis and HDM, respectively, and 91 patients (49%) were alive at the last follow-up 52 months (median) from HDM. Thirty patients (16%) died within 100 days of transplantation; only low serum albumin predicted early deaths. Overall, hematologic response (HR) and cardiac responses were seen in 66% and 41% of patients, respectively. The median OS for patients with and without HR was not reached and 22 months, respectively (P < .01); and for those with any decrease and no decrease in N-terminal-pro-brain natriuretic peptide was not reached and 26 months, respectively (P < .01). In multivariate analysis of baseline factors, only reduced-dose melphalan predicted shorter OS. HDM is feasible in patients with cardiac amyloidosis, and achievement of HR and organ response is associated with improved survival.
Intracardiac Thrombosis and Anticoagulation Therapy in Cardiac Amyloidosis
Background— Primary amyloidosis has a poor prognosis as a result of frequent cardiac involvement. We recently reported a high prevalence of intracardiac thrombus in cardiac amyloid patients at autopsy. However, neither the prevalence nor the effect of anticoagulation on intracardiac thrombus has been evaluated antemortem. Methods and Results— We studied all transthoracic and transesophageal echocardiograms of cardiac amyloid patients at the Mayo Clinic. The prevalence of intracardiac thrombosis, clinical and transthoracic/transesophageal echocardiographic risks for intracardiac thrombosis, and effect of anticoagulation were investigated. We identified 156 patients with cardiac amyloidosis who underwent transesophageal echocardiograms. Amyloidosis was the primary type (AL) in 80; other types occurred in 76 patients, including 56 with the wild transthyretin type, 17 with the mutant transthyretin type, and 3 with the secondary type. Fifth-eight intracardiac thrombi were identified in 42 patients (27%). AL amyloid had more frequent intracardiac thrombus than the other types (35% versus 18%; P =0.02), although the AL patients were younger and had less atrial fibrillation. Multivariate analysis showed that atrial fibrillation, poor left ventricular diastolic function, and lower left atrial appendage emptying velocity were independently associated with increased risk for intracardiac thrombosis, whereas anticoagulation was associated with a significantly decreased risk (odds ratio, 0.09; 95% CI, 0.01 to 0.51; P <0.006). Conclusions— Intracardiac thrombosis occurs frequently in cardiac amyloid patients, especially in the AL type and in those with atrial fibrillation. Risk for thrombosis increased if left ventricular diastolic dysfunction and atrial mechanical dysfunction were present. Anticoagulation therapy appears protective. Timely screening in high-risk patients may allow early detection of intracardiac thrombus. Anticoagulation should be carefully considered.
Intracardiac Thrombosis and Embolism in Patients With Cardiac Amyloidosis
Background— Patients with primary amyloidosis (AL type) have a poor prognosis, in part due to frequent cardiac involvement. Although intracardiac thrombus has been reported in anecdotal cases, neither its frequency nor its role in causing mortality is known. Furthermore, the clinical and echocardiographic variables that may be associated with thromboembolism in cardiac amyloidosis have not been defined. Methods and Results— A total of 116 autopsy or explanted cases of cardiac amyloidosis (55 AL and 61 other type) were identified in the Mayo Clinic. Forty-six fatal nonamyloid trauma cases served as controls. Each heart was examined for intracardiac thrombus. The cause of death was determined from autopsy and clinical notes. Intracardiac thrombosis was identified in 38 hearts (33%). Twenty-three had 1 thrombus, whereas 15 had 2 to 5 thrombi. Although subjects in the AL group were younger and had less atrial fibrillation than those with other types of amyloidosis, the AL group had significantly more intracardiac thrombus (51% versus 16%, P <0.001) and more fatal embolic events (26% versus 8%, P <0.03). Control hearts had no intracardiac thrombus. The presence of both atrial fibrillation and AL was associated with an extremely high risk for thromboembolism (odds ratio 55.0 [95% confidence interval 8.1 to 1131.4]). By multivariate analysis, AL type (odds ratio 8.4 [95% confidence interval 1.8 to 51.2]) and left ventricular diastolic dysfunction (odds ratio 12.2 [95% confidence interval 2.7 to 72.7]) were independently associated with thromboembolism. Conclusions— A high frequency of intracardiac thrombosis was present in cardiac amyloidosis. Furthermore, thromboembolism caused significant fatality. Several risk factors for thromboembolism were identified. Early screening, especially in high-risk patients, and early anticoagulation might reduce morbidity and mortality.