Pacemaker and implantable cardioverter-defibrillator use in a US myotonic dystrophy type 1 population.
BACKGROUND
We assessed implant rates, indications, characteristics, and outcomes in patients with the neuromuscular disease, myotonic dystrophy type 1 (DM1) receiving a pacemaker or an implantable cardioverter-defibrillator (ICD).


RESULTS
Device use was evaluated in a prospective, multicenter registry of 406 genetically confirmed adult patients followed for 9.5 ± 3.2 years. Forty-six (11.3%) had or received a pacemaker and 21 (5.2%) received an ICD. Devices were primarily implanted for asymptomatic conduction abnormalities and left ventricular (LV) systolic dysfunction. However, 7 (15.2%) pacemakers were implanted for third-degree atrioventricular block and 6 (28.6%) ICDs were implanted for ventricular tachyarrhythmias (ventricular tachycardia [VT] or fibrillation [VF]). Patients receiving devices were older and more frequently had heart failure, LV systolic dysfunction, atrial tachyarrhythmias, and ECG conduction abnormalities compared to nondevice patients. Five (10.9%) pacemaker patients underwent upgrade to an ICD, 3 for LV systolic dysfunction, 1 for VT/VF, and 1 for progressive conduction disease. Seventeen (27.4%) of the 62 patients with devices were pacemaker-dependent at last follow-up. Three (14.3%) ICD patients had appropriate therapies. Twenty-four (52.2%) pacemaker patients died including 13 of respiratory failure and 7 of sudden death. Seven (33.3%) ICD patients died including 2 of respiratory failure and 3 of sudden death. The patients with ICDs and sudden death all had LV systolic dysfunction and 1 death was documented due to inappropriate therapies.


CONCLUSIONS
DM1 patients commonly receive antiarrhythmia devices. The risk of VT/VF and sudden death suggests that ICDs rather than pacemakers should be considered for these patients.
Division of Cardiology, Department of Medicine, Krannert Institute of Cardiology Department of Biostatistics, Indiana University, Indianapolis, Indiana, USA.
Deepak
D
Bhakta
Changyu
C
Shen
Jack
J
Kron
Andrew E
AE
Epstein
Robert M
RM
Pascuzzi
William J
WJ
Groh
D000328:Adult; D000368:Aged; D017147:Defibrillators, Implantable; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009223:Myotonic Dystrophy / Q000150:complications*; D010138:Pacemaker, Artificial; D011446:Prospective Studies; D017180:Tachycardia, Ventricular / Q000401:mortality / Q000628:therapy; D014693:Ventricular Fibrillation / Q000401:mortality / Q000628:therapy