title: External counterpulsation therapy improves endothelial function in patients with refractory angina pectoris.
abstract: OBJECTIVE
  The goal of this study was to investigate the influence of short-term external counterpulsation (ECP) therapy on flow-mediated dilation (FMD) in patients with coronary artery disease (CAD).
  
  
  BACKGROUND
  In patients with CAD, the vascular endothelium is usually impaired and modification or reversal of endothelial dysfunction may significantly enhance treatment. Although ECP therapy reduces angina and improves exercise tolerance in patients with CAD, its short-term effects on FMD in patients with refractory angina pectoris have not yet been described.
  
  
  METHODS
  We prospectively assessed endothelial function in 20 consecutive CAD patients (15 males), mean age 68 +/- 11 years, with refractory angina pectoris (Canadian Cardiovascular Society [CCS] angina class III to IV), unsuitable for coronary revascularization, before and after ECP, and compared them with 20 age- and gender-matched controls. Endothelium-dependent brachial artery FMD and endothelium-independent nitroglycerin (NTG)-mediated vasodilation were assessed before and after ECP therapy, using high-resolution ultrasound.
  
  
  RESULTS
  External counterpulsation therapy resulted in significant improvement in post-intervention FMD (8.2 +/- 2.1%, p = 0.01), compared with controls (3.1 +/- 2.2%, p = 0.78). There was no significant effect of treatment on NTG-induced vasodilation between ECP and controls (10.7 +/- 2.8% vs. 10.2 +/- 2.4%, p = 0.85). External counterpulsation significantly improved anginal symptoms assessed by reduction in mean sublingual daily nitrate consumption, compared with controls (4.2 +/- 2.7 nitrate tablets vs. 0.4 +/- 0.5 nitrate tablets, p <0.001 and 4.5 +/- 2.3 nitrate tablets vs. 4.4 +/- 2.6 nitrate tablets, p = 0.87, respectively) and in mean CCS angina class compared with controls (3.5 +/- 0.5 vs. 1.9 +/- 0.3, p <0.0001 and 3.3 +/- 0.6 vs. 3.5 +/- 0.5, p = 0.89, respectively).
  
  
  CONCLUSIONS
  External counterpulsation significantly improved vascular endothelial function in CAD patients with refractory angina pectoris, thereby suggesting that improved anginal symptoms may be the result of such a mechanism.
authors.affiliation: Heart Institute, Chaim Sheba Medical Center, and Sackler Faculty of Medicine, Tel Aviv University, Tel Hashomer, Israel. schectes@netvision.net.il
authors.forename: Michael
authors.initials: M
authors.lastname: Shechter
authors.forename: Shlomi
authors.initials: S
authors.lastname: Matetzky
authors.forename: Micha S
authors.initials: MS
authors.lastname: Feinberg
authors.forename: Pierre
authors.initials: P
authors.lastname: Chouraqui
authors.forename: Zeev
authors.initials: Z
authors.lastname: Rotstein
authors.forename: Hanoch
authors.initials: H
authors.lastname: Hod
mesh_terms: D000368:Aged; D000787:Angina Pectoris / Q000628:therapy*; D003327:Coronary Disease / Q000628:therapy; D015908:Counterpulsation / Q000379:methods; D004730:Endothelium, Vascular / Q000502:physiology*; D006801:Humans; D008297:Male; D005996:Nitroglycerin / Q000627:therapeutic use; D011446:Prospective Studies; D014664:Vasodilation / Q000502:physiology
chemical_list: D005996:Nitroglycerin