Impact of Routine Angiographic Follow-Up on the Clinical Benefits of Paclitaxel-Eluting Stents: Results From the TAXUS-IV Trial

Impact of Routine Angiographic Follow-Up on the Clinical Benefits of Paclitaxel-Eluting Stents: Results From the TAXUS-IV Trial

Duane S. Pinto, Gregg W. Stone, Stephen G. Ellis, David A. Cox, James Hermiller, Charles O’Shaughnessy, J. Tift Mann, Roxana Mehran, Yingbo Na, Mark Turco, Ronald Caputo, Jeffrey J. Popma, Donald E. Cutlip, Mary E. Russell, David J. Cohen, for the TAXUS-IV Investigators

We compared 1-year clinical outcomes among patients randomized to the Taxus paclitaxel-eluting stent (PES) or an identical-appearing bare-metal stent in the TAXUS-IV (2-Year Results of In-Stent Restenosis Treated With the Slow-Release Polymer-Based Paclitaxel-Eluting Taxus Stent) trial, stratified by assignment to mandatory angiographic follow-up or clinical follow-up alone. Compared with clinical follow-up alone, performance of mandatory angiographic follow-up increased rates of target vessel revascularization by ∼40% among patients receiving either bare metal or drug-eluting stents. Nonetheless, the rate of target vessel revascularization was reduced substantially by PES regardless of whether angiographic follow-up was mandated.

Objectives

The objectives of the study were to evaluate the effect of angiographic follow-up on revascularization rates in the TAXUS-IV trial and to determine whether the relative benefit of paclitaxel-eluting stent implantation compared with bare metal stent implantation was modified by angiographic follow-up.

Background

Although several clinical trials have demonstrated that drug-eluting stents (DES) reduce restenosis compared with bare-metal stents (BMS), virtually all of these studies have incorporated angiographic follow-up.

Methods

In the TAXUS-IV trial, 1,314 percutaneous coronary intervention patients were randomized to receive paclitaxel-eluting stents (PES) (n = 662) or identical-appearing BMS (n = 652). Clinical outcomes were compared, stratified by assignment to angiographic follow-up or clinical follow-up alone.

Results

Compared with clinical follow-up alone, angiographic follow-up patients had a significantly higher rate of target vessel revascularization (TVR) at 1 year (adjusted hazard ratio [HR] 1.46; p = 0.04), with similar relative increases in PES and BMS patients. Because PES reduced TVR by ∼60% regardless of type of follow-up, assignment to angiographic follow-up tended to overestimate the absolute benefit of PES relative to clinical follow-up alone. In contrast, assessment of end points immediately before the time of follow-up angiography led to substantial underestimation of the absolute benefit of PES implantation.

Conclusions

Performance of mandatory angiographic follow-up increases rates of TVR among patients receiving both BMS and PES and overestimates the absolute clinical benefits of PES relative to clinical follow-up alone. Nonetheless, PES substantially reduces TVR regardless of assignment to mandatory angiographic follow-up or not. Future studies designed to determine the true clinical benefits of DES should either forgo routine angiographic follow-up or separate the time of repeat angiography from the primary clinical end point by as long as possible.