Angiographic and clinical outcomes of drug-eluting versus bare metal stent deployment in the Occluded Artery Trial

Abstract

Background: The majority of patients randomized to percutaneous coronary intervention (PCI) in the Occluded Artery Trial (OAT) and its angiographic substudy, the Total Occlusion Study of Canada 2 (TOSCA-2) were treated with bare metal stents (BMS). We aimed to determine if stenting of the target occlusion in OAT with drug-eluting stents (DES) was associated with more favorable angiographic results and clinical outcome when compared with treatment with BMS.

Methods: TOSCA-2 DES was a prospective nonrandomized substudy that provided 1-year angiographic comparison of late loss and reocclusion in 25 patients treated with DES and in 128 treated with BMS. In addition, all PCI-assigned patients enrolled from the time when DES were first utilized were similarly categorized (DES n = 77, and BMS n = 386) and compared using the 3-year cumulative OAT primary combined endpoint of death, myocardial infarction, or Class-IV heart failure, as well as angina.

Results: In-segment late loss was 0.14 +/- 0.45 mm for DES and 0.75 +/- 0.86 mm for BMS (P < 0.001). Corresponding binary restenosis rates were 13.0% and 44.3% (P = 0.005). Occlusion at 1 year was observed in 4.0 and 12.1%, respectively (P = 0.23). The 3-year cumulative primary event rate was 13.8% with DES and 12.5% with BMS (hazard ratio 1.08, 99% confidence intervals 0.44, 2.64; P = 0.83). Angina over time occurred less frequently in the DES group (P = 0.01).

Conclusions: Although the reduction of late loss and trend to reduction in reocclusion with the use of DES for PCI of persistently occluded IRA 3-28 days post myocardial infarction did not translate into a signal for reduction in death, reinfarction, or Class IV heart failure, DES use was associated with less angina over time. Further follow-up is warranted.

Fig. 1

Kaplan-Meier curves for the OAT combined primary endpoint comparing the DES- and BMS-treated patients in the PCI arm of OAT. red = BMS, green = DES. [Color figure can be viewed in the online issue, which is available at www.interscience.wiley.com.]

Fig. 2

Kaplan-Meier curves for the individual secondary clinical endpoints death, reinfarction, and NYHA Class IV heart failure comparing the DES- and BMS-treated patients in the PCI arm of OAT. red = BMS, blue = DES. [Color figure can be viewed in the online issue, which is available at www.interscience.wiley.com.]

Fig. 3

Kaplan-Meier curves for repeat revascularization by PCI or CABG comparing the DES- and BMS-treated patients in the PCI arm of OAT. red = BMS, green = DES. [Color figure can be viewed in the online issue, which is available at www.interscience.wiley.com.]

Fig. 4

Rates of any angina in the OAT DES- and BMS-treated patients at 4 months and 1, 2, and 3 years of follow-up. red = BMS, green = DES. [Color figure can be viewed in the online issue, which is available at www.interscience.wiley.com.]