Incidence of Bradycardia and Outcomes of Patients Who Underwent Orbital Atherectomy Without a Temporary Pacemaker.
OBJECTIVE
We analyzed the incidence of bradycardia and the safety of patients with severely calcified coronary lesions who underwent orbital atherectomy without the insertion of a temporary pacemaker.


BACKGROUND
The presence of severely calcified coronary lesions can increase the complexity of percutaneous coronary intervention due to the difficulty in advancing and optimally expanding the stent. High-pressure inflations to predilate calcified lesions may cause angiographic complications like perforation and dissection. Suboptimal stent expansion is associated with stent thrombosis and restenosis. Orbital atherectomy safely and effectively modifies calcified plaque to facilitate optimal stent expansion. The incidence of bradycardia in orbital atherectomy is unknown.


METHODS
Fifty consecutive patients underwent orbital atherectomy from February 2014 to September 2016 at our institution, none of whom underwent insertion of a temporary pacemaker. The final analysis included 47 patients in this retrospective study as 3 patients were excluded because of permanent pacemaker implantation. The primary endpoint was significant bradycardia, defined as bradycardia requiring emergent pacemaker placement or a heart rate <50 bpm at the end of atherectomy.


RESULTS
The primary endpoint occurred in 4% of all patients, all driven by patients who experienced a heart rate decreasing to <50 bpm. The major adverse cardiac and cerebral event rate was 6%, driven by death (2%) and myocardial infarction (4%). No patient experienced target-vessel revascularization, stroke, or stent thrombosis. Angiographic complications included perforation in 2%, slow-flow in 4%, and flow-limiting dissection in 0%.


CONCLUSIONS
Significant bradycardia was uncommon during orbital atherectomy. Performing orbital atherectomy without a temporary pacemaker appears to be safe.
Division of Interventional Cardiology, UCLA Medical Center, Los Angeles, California, 100 Medical Plaza, Suite 630, Los Angeles, CA 90095 USA. mslee@mednet.ucla.edu.
Michael S
MS
Lee
Heajung
H
Nguyen
Richard
R
Shlofmitz
D017225:Atherectomy, Coronary / Q000009:adverse effects*; D001919:Bradycardia / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology; D002140:California / Q000453:epidemiology; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000601:surgery*; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000601:surgery*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D011183:Postoperative Complications; D012189:Retrospective Studies; D061205:Vascular Calcification / Q000175:diagnosis / Q000601:surgery*