title: Temporary Transvenous Pacemaker Implantation during Carotid Endarterectomy in Patients with Trifascicular Block.
abstract: BACKGROUND
  The risk of severe perioperative bradyarrhythmias in patients with chronic left bundle branch, or bifascicular block, and an additional first-degree atrioventricular block undergoing carotid endarterectomy (CEA) has never been specifically addressed. In this study, we aimed to investigate whether these conduction abnormalities entail an increased risk of hemodynamic compromise during CEA and the role of temporary transvenous pacemaker (TTVPM) implantation as a prophylactic measure in this subgroup of patients.
  
  
  METHODS
  Between June 2006 and June 2013, 37 CEAs were performed in 31 patients (29 men, mean age 76 ± 6 years), in whom a TTVPM was implanted for a trifascicular block. Thirty-seven concurrent, consecutive patients operated for other vascular pathologies also with a prophylactic TTVPM for an asymptomatic trifascicular block served as controls. Adverse events were considered: pacemaker activation, block progression, bradycardia ≤40 beats/min, and asystole.
  
  
  RESULTS
  Study and control groups were overall comparable. No perioperative mortality was recorded. All patients undergoing CEA were asymptomatic for syncope preoperatively. Among them, in 34 cases, indication for TTVPM was based on preoperative EKG, and in 4, a pacemaker activation was recorded. Three additional patients were also included in the study group in whom TTVPM was implanted due to the occurrence of adverse advents, and not prophylactically. In 2 of these, severe bradycardia with eventual asystole occurred intraoperatively. In both cases, the procedure was discontinued and rescheduled for the following day after a TTVPM was implanted. In the last additional case, the patient had a block progression on day 1 after an uneventful CEA and was emergently treated with a TTVPM. Overall, 7 adverse events were recorded in the study group, and none in the control group (P < 0.011). Morbidity in the CEA group also included 1 myocardial infarction, 1 minor stroke, 1 surgical revision for cervical hematoma, 1 new-onset atrial fibrillation, and 1 femoral artery pseudoaneurysm.
  
  
  CONCLUSIONS
  In our experience, TTVPM implantation was a clinically useful adjunct in patients with trifascicular block submitted to CEA, as compared with other vascular surgical procedures. However, the risks inherent to CEA in this subgroup of patients suggest that surgical treatment may not be warranted for those with asymptomatic carotid disease.
authors.affiliation: Cardiothoracic and Vascular Department, Vascular Surgery Unit, IRCCS Ospedale San Raffaele, Milano, Italy. Electronic address: max_marrocco@yahoo.com.
authors.forename: Massimiliano M
authors.initials: MM
authors.lastname: Marrocco-Trischitta
authors.affiliation: Cardiothoracic and Vascular Department, Arrhythmology and Cardiac Pacing Unit, IRCCS Ospedale San Raffaele, Milano, Italy.
authors.forename: Patrizio
authors.initials: P
authors.lastname: Mazzone
authors.affiliation: Cardiothoracic and Vascular Department, Vascular Surgery Unit, IRCCS Ospedale San Raffaele, Milano, Italy.
authors.forename: Renato
authors.initials: R
authors.lastname: Vitale
authors.affiliation: Cardiothoracic and Vascular Department, Arrhythmology and Cardiac Pacing Unit, IRCCS Ospedale San Raffaele, Milano, Italy.
authors.forename: Damiano
authors.initials: D
authors.lastname: Regazzoli
authors.affiliation: Cardiothoracic and Vascular Department, Cardiology Unit, IRCCS Ospedale San Raffaele, Milano, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Laricchia
authors.affiliation: Cardiothoracic and Vascular Department, Vascular Surgery Unit, IRCCS Ospedale San Raffaele, Milano, Italy; Cardiothoracic and Vascular Department, IRCCS Ospedale San Raffaele, Università Vita-Salute San Raffaele, Milano, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Chiesa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D058070:Asymptomatic Diseases; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects; D002340:Carotid Artery Diseases / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D004562:Electrocardiography; D016894:Endarterectomy, Carotid / Q000009:adverse effects; D004867:Equipment Design; D005260:Female; D006327:Heart Block / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D006439:Hemodynamics; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial; D018579:Patient Selection; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome