The platelet glycoprotein Ia C807T polymorphism as risk factor for coronary catheter interventions

To the editor:

In a recent paper, the results of a carefully performed study on the association between the glycoprotein (GP) Ia C807T polymorphism and procedural risk after coronary artery stenting were reported.1 The authors concluded that the 807T genotype, which is associated with higher platelet-surface expression of GP Ia/IIa, had no significant influence on major adverse events occurring after coronary artery stenting.1 Because the implantation of stents induces marked platelet activation, we wondered if these results might also apply to coronary interventions without stent implantation, that is, plain angioplasty (PTCA) and directional coronary atherectomy (DCA).

In a prospective study of 673 patients who underwent coronary interventions (PTCA, DCA, and stenting), we performed genotyping for the GP Ia C807T polymorphism and followed the patients for a 30-day composite endpoint, including need for target vessel revascularization (repeat PTCA or bypass grafting), myocardial infarction, and death. Operational techniques, indications for coronary interventions, baseline, and the patients' clinical characteristics have been described in detail elsewhere.2 Genotyping (by PCR/RFLP according to Kritzik et al3) was successful for 272 patients who underwent PTCA, for 104 with DCA, and for 276 who were treated by stenting. Genotype distribution was CC in 35.3%, CT in 49.7%, and TT in 15.0%, results comparable to reported data.1 Our results regarding early complications after stent implantation confirm those reported by von Beckerath et al.1 In addition, our data provide evidence that the GP Ia 807T genotype is, likewise, not a risk factor for adverse events following PTCA and DCA (Table). Data did not change after construction of a multivariate model that included baseline risk factors, coagulation parameters, and procedural determinants. We conclude from our data, together with other results reported previously,1 that the GP Ia 807T genotype does not predict adverse outcome after coronary interventions, regardless of whether or not stents are implanted.