title: Effectiveness of enhanced external counterpulsation in patients with left main disease and angina.
abstract: BACKGROUND
  Enhanced external counterpulsation (EECP) is a noninvasive device that uses three pairs of sequentially inflated pneumatic cuffs applied to the lower extremities and synchronized with the heart beat to provide diastolic augmentation, increase coronary blood pressure and flow, venous return and cardiac output, and decrease afterload.
  
  
  OBJECTIVE
  This study examines the safety and effectiveness of EECP therapy in patients with significant left main coronary artery disease (LMD).
  
  
  METHODS
  In all, 2,861 patients enrolled in the International EECP Patient Registry (IEPR) were divided into three groups, those without LMD (n = 2,377), those with LMD and prior CABG (n = 431), and those with unbypassed LMD (n = 53).
  
  
  RESULTS
  Patients with LMD, with or without prior CABG, were significantly more likely to have triple-vessel disease (98.1 and 88.7%, respectively) than patients without LMD (41.9%). Post-EECP, 74% without LMD, 75% with LMD with prior CABG, and 65% with unbypassed LMD improved their Canadian Cardiovascular Society (CCS) angina by at least one class (p = NS). There were no differences in the mean decrease in weekly angina episodes (7.1 vs. 8.0 vs. 7.6) and in the mean frequency of weekly nitroglycerin use (6.6 vs. 8.1 vs. 8.9). At 6-month follow-up, the CCS class improved further in all three groups, and there was a further reduction in mean weekly angina episodes (4.7 vs. 4.6 vs. 5.3) and nitroglycerin use (6.5 vs. 6.8 vs. 8.2). Kaplan-Meier life table analysis 8 months after starting EECP demonstrated a major cardiovascular event rate of 11.2% in patients without LMD, 15.6% in LMD with CABG, and 24.3% in LMD without prior CABG. Late mortality in unbypassed LMD was 13.2% (confidence interval [CI] 3.3-23.1) versus 4.8% (CI 2.7-7.1) in LMD with CABG, and 2.8% (CI 2.1-3.5) without LMD (p = 0.0039 by log-rank test).
  
  
  CONCLUSIONS
  Enhanced external counterpulsation is equally effective in relieving angina in patients with or without LMD. However, the significantly increased late mortality in patients with LMD without prior CABG suggests that early revascularization should be considered in these patients.
authors.affiliation: SUNY Stony Brook, Stony Brook, New York 11740, USA. william.lawson@stonybrook.edu
authors.forename: William E
authors.initials: WE
authors.lastname: Lawson
authors.forename: John C K
authors.initials: JC
authors.lastname: Hui
authors.forename: Gregory W
authors.initials: GW
authors.lastname: Barsness
authors.forename: Elizabeth D
authors.initials: ED
authors.lastname: Kennard
authors.forename: Sheryl F
authors.initials: SF
authors.lastname: Kelsey
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000787:Angina Pectoris / Q000628:therapy*; D016009:Chi-Square Distribution; D015331:Cohort Studies; D001026:Coronary Artery Bypass; D003324:Coronary Artery Disease / Q000628:therapy*; D015908:Counterpulsation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome