Lack of association between baseline plasma homocysteine concentrations and restenosis rates after a first elective percutaneous coronary intervention without stenting

Objective: To evaluate the association between baseline homocysteine concentrations and restenosis rates in patients electively undergoing their first percutaneous coronary intervention (PCI) without stenting. Design: Prospective, single centre, observational study. Setting and patients: Patients electively undergoing their first PCI without stenting at a tertiary referral centre between 1990 and 1998. Methods: Blood samples were collected from all patients at baseline and assayed to determine the patients' homocysteine concentrations. Patients whose PCI was successful underwent repeat angiography at a median of 6.4 (interquartile range 6-6.8) months. Their baseline and follow up angiograms were compared by quantitative coronary angiography to assess the incidence of restenosis. For the analysis, the patients were divided into two groups based on whether their baseline homocysteine concentrations were above or below the median value. These two groups were compared to determine whether there was any association between their baseline homocysteine concentrations and the incidence of restenosis at six months. Results: 134 patients had a successful first PCI without stenting ( involving 200 lesions). At six month angiography, restenosis was observed in 33 patients (49.3%) with baseline homocysteine concentrations above the median value and in 31 patients (46.3%) with concentrations below the median value (p=0.74). There was no difference in the percentage of lesions developing restenosis (38(39.6%) v 40 (38.5%), respectively, p=0.87) or late lumen loss (0.40 mm v 0.31 mm, respectively, p=0.24). On multivariable analysis, there was no association between homocysteine concentrations and late lumen loss (r=20.11, p=0.11) or the percentage diameter stenosis at follow up (r=20.07, p=0.32). Conclusion: Baseline homocysteine concentrations were not associated with six month restenosis rates in patients electively undergoing their first PCI without stenting.