title: Determinants and outcomes of asystole during carotid artery stenting.
abstract: OBJECTIVE
  To examine the predictors and outcomes of asystole in patients who undergo carotid artery stenting (CAS).
  
  
  METHODS
  Forty-three patients (24 men; median age 69 years) with asystole were identified after reviewing the case records of 884 patients who underwent CAS at our institution between 1997 and 2009. The control group comprised 678 patients who underwent stenting in the carotid sinus area without asystole. Univariate and multivariate logistic analyses were used to determine the predictors and outcomes of asystole.
  
  
  RESULTS
  A right-sided procedure was more likely to result in asystole [odds ratio (OR) 11.4, 95% CI 4.0 to 32.7, p<0.0001] compared with a left-sided procedure. Patients with a contralateral carotid stenosis (OR 1.7, 95% CI 1.0 to 2.8, p = 0.04) and a left ventricular ejection fraction (LVEF) of <40% (OR 2.2, 95% CI 1.1 to 4.5, p = 0.03) were also more likely to suffer asystole. Smokers appeared less likely to develop asystole (OR 0.25, 95% CI 0.12 to 0.56, p = 0.0006). Periprocedural stroke (14% vs. 1.3%, p<0.001), length of stay during index hospitalization (2.2 vs. 1.2 days, p = 0.002), and 30-day mortality (11.6% vs. 4.1%, p = 0.02) were significantly higher in the asystole group.
  
  
  CONCLUSIONS
  Asystole during CAS is more likely to occur in patients undergoing procedures in the right carotid sinus area, in those who have significant contralateral carotid stenosis, and in those with a reduced LVEF. More caution should be exercised during right-sided than left-sided CAS procedures.
authors.affiliation: Department of Cardiology, Texas Heart Institute at St. Luke's Episcopal Hospital, Houston, Texas, USA.
authors.forename: Kumar
authors.initials: K
authors.lastname: Satya
authors.forename: Kathy
authors.initials: K
authors.lastname: Dougherty
authors.forename: Vei-Vei
authors.initials: VV
authors.lastname: Lee
authors.forename: Neil
authors.initials: N
authors.lastname: Strickman
authors.forename: Ali
authors.initials: A
authors.lastname: Mortazavi
authors.forename: Arup
authors.initials: A
authors.lastname: Achari
authors.forename: Emerson
authors.initials: E
authors.lastname: Perin
authors.forename: Zvonimir
authors.initials: Z
authors.lastname: Krajcer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000800:Angioplasty, Balloon / Q000009:adverse effects* / Q000295:instrumentation*; D016893:Carotid Stenosis / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D005260:Female; D006323:Heart Arrest / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D015607:Stents; D013318:Stroke Volume; D013781:Texas; D016896:Treatment Outcome; D016277:Ventricular Function, Left