Prophylactic implantation of cardioverter-defibrillator in patients with severe cardiac amyloidosis and high risk for sudden cardiac death.
BACKGROUND
Cardiac light-chain amyloidosis carries a high risk for death predominantly from progressive cardiomyopathy or sudden death (SCD). Independent risk factors for SCD are syncope and complex nonsustained ventricular arrhythmias.


OBJECTIVE
The purpose of this study was to test whether prophylactic placement of an implantable cardioverter-defibrillator (ICD) reduces SCD in patients with cardiac amyloidosis.


METHODS
Nineteen patients with histologically proven cardiac amyloidosis and a history of syncope and/or ventricular extra beats (Lown grade IVa or higher) received an ICD.


RESULTS
During a mean follow-up of 811 +/- 151 days, two patients with sustained ventricular tachyarrhythmias were successfully treated by the ICD. Two patients underwent heart transplantation, and seven patients died due to electromechanical dissociation (n = 6) or glioblastoma (n = 1). Nonsurvivors more often showed progression of left ventricular wall thickness, low-voltage pattern, ventricular arrhythmias (Lown grade IVa or higher), and higher N-terminal pro-brain natriuretic peptide levels than did survivors. Bradycardias requiring ventricular pacing (VVI 40/min <1%, DDD 60/min 6% +/- 1%) occurred only rarely.


CONCLUSIONS
Patients with cardiac amyloidosis predominantly die as a result of electromechanical dissociation and other diagnoses not amenable to ICD therapy. Selected patients with cardiac amyloidosis may benefit from ICD placement. Better predictors of arrhythmia-associated SCD and randomized trials are required to elucidate the impact of ICD placement in high-risk patients with cardiac amyloidosis.
Kristen
Arnt V
AV
Department of Cardiology, Angiology, and Respiratory Medicine, University Hospital Heidelberg, Heidelberg, Germany. Arnt_Kristen@med.uni-heidelberg.de
Dengler
Thomas J
TJ
Hegenbart
Ute
U
Schonland
Stefan O
SO
Goldschmidt
Hartmut
H
Sack
Falk-Udo
FU
Voss
Frederik
F
Becker
Rüdiger
R
Katus
Hugo A
HA
Bauer
Alexander
A
D000328:Adult; D000686:Amyloidosis / Q000150:complications*; D009202:Cardiomyopathies / Q000209:etiology / Q000517:prevention & control*; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control*; D017147:Defibrillators, Implantable; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D012107:Research Design; D018570:Risk Assessment; D012307:Risk Factors; D014693:Ventricular Fibrillation / Q000517:prevention & control