title: Impaired intravascular triglyceride lipolysis constitutes a marker of clinical outcome in patients with stable angina undergoing secondary prevention treatment: a long-term follow-up study.
abstract: OBJECTIVE
  We sought to verify whether the intravascular metabolism of chylomicron-like emulsion may predict the clinical evolution of patients with coronary artery disease (CAD) undergoing secondary prevention therapy of CAD.
  
  
  BACKGROUND
  Case-control studies have suggested an association between impaired intravascular catabolism of triglyceride (TG)-rich lipoproteins and CAD. However, evidence is lacking with respect to the potential clinical relevance of this metabolic disorder in CAD patients.
  
  
  METHODS
  During a period of 4.5 +/- 0.9 years, we followed up 63 stable CAD patients (mean age 60 +/- 10 years) undergoing secondary prevention therapy (low-density lipoprotein cholesterol <100 mg/dl) in whom kinetic studies of the in vivo catabolism of chylomicron-like emulsions were performed. At enrollment into the study, fasting patients were injected intravenously with a chylomicron-like emulsion labeled with radioactive triglyceride (3H-TG) and cholesteryl esters (14C-CE) to evaluate the efficacy of intravascular TG lipolysis.
  
  
  RESULTS
  At baseline, CAD patients displayed a diminished fractional clearance rate (FCR) for 3H-TG (-26%; p = 0.027), for 14C-CE (-37%; p = 0.015), and for delipidation index (DI) (-26%; p = 0.02) as compared with 35 control subjects. During follow-up of secondary prevention therapy, 33% of CAD patients (n = 21) presented with clinically refractory angina and aggravated coronary angiographic severity. The FCR for 3H-TG (-44%; p = 0.005) and DI (-41%; p = 0.006) in those patients with refractory angina was significantly lower than that observed in those with stable evolution. Moreover, in a Cox multivariate regression analysis, the presence of a DI less than the median value was an independent predictor of an unfavorable clinical evolution (adjusted hazard ratio 3.32; 95% confidence interval 1.21 to 9.14; p = 0.020).
  
  
  CONCLUSIONS
  The current study establishes that delayed intravascular TG lipolysis is a strong and independent predictor of evolution to severe angina among patients undergoing secondary prevention therapy of CAD.
authors.affiliation: Heart Institute (InCor), Zerbini Foundation, Brasilia, Brazil.
authors.forename: Andrei C
authors.initials: AC
authors.lastname: Sposito
authors.forename: Pedro A
authors.initials: PA
authors.lastname: Lemos
authors.forename: Raul D
authors.initials: RD
authors.lastname: Santos
authors.forename: Whady
authors.initials: W
authors.lastname: Hueb
authors.forename: Carmen G C
authors.initials: CG
authors.lastname: Vinagre
authors.forename: Edgard
authors.initials: E
authors.lastname: Quintella
authors.forename: Otavio
authors.initials: O
authors.lastname: Carneiro
authors.forename: M John
authors.initials: MJ
authors.lastname: Chapman
authors.forename: Jose A F
authors.initials: JA
authors.lastname: Ramires
authors.forename: Raul C
authors.initials: RC
authors.lastname: Maranhão
mesh_terms: D000328:Adult; D000368:Aged; D000787:Angina Pectoris / Q000378:metabolism* / Q000503:physiopathology / Q000517:prevention & control*; D015415:Biomarkers / Q000097:blood; D001938:Brazil; D008076:Cholesterol, HDL / Q000097:blood / Q000187:drug effects; D008078:Cholesterol, LDL / Q000097:blood / Q000187:drug effects; D015243:Cholesterol, VLDL / Q000097:blood / Q000187:drug effects; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000378:metabolism / Q000503:physiopathology / Q000517:prevention & control*; D004655:Emulsions; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D000960:Hypolipidemic Agents / Q000627:therapeutic use*; D008066:Lipolysis / Q000187:drug effects* / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D013318:Stroke Volume / Q000502:physiology; D013995:Time; D016896:Treatment Outcome; D014280:Triglycerides / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D015243:Cholesterol, VLDL; D004655:Emulsions; D000960:Hypolipidemic Agents; D014280:Triglycerides