Do drug-eluting stents give equal patency rates to Coronary arterial bypass grafts
Date First Published:
June 22, 2003
Last Updated:
June 22, 2003
Report by:
Joel Dunning, RCS Research Fellow (Manchester Royal Infirmary)
Three-Part Question:
In [patients with significant coronary artery stenoses] are [drug eluting stents compared to conventional CABG] the optimal method to achieve [long term graft patency]?
Clinical Scenario:
You are seeing a 70 year old American man with three discrete 70% stenoses in the mid LAD, mid Circumflex and Proximal RCA. He has grade III angina and apart from Hypertension and a high cholesterol he has no other significant past history. You advise him that his best option is certainly to have Coronary Arterial Bypass grafts in terms of relief of symptoms. However he tells you that he had a friend in the States with the same problems as him who had 3 stents that were impregnated with drugs that will keep his arteries open forever. You wonder whether drug-eluting stents would be just as good for him if he could get them.
Search Strategy:
Medline 1966-06/03 using the OVID interface.
Search Details:
[exp sirolimus/ OR sirolimus.mp OR exp paclitaxel/ OR paclitaxel.mp OR Drug-eluting.mp OR heparin-coated.mp OR rapamycin.mp] AND [exp Stents/ OR stent.mp]
Outcome:
197 papers were found of which 8 were deemed to be relevant.
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Stenting in small coronary arteries (SISCA) trial. A randomized comparison between balloon angioplasty and the heparin-coated beStent. Moer R, Myreng Y, Molstad P, et al. 2001 | 145 patients with stable or unstable angina were randomly assigned to elective stenting treatment with the heparin (Hepamed)-coated beStent or PTCA | Double blind RCT | Event-free survival at follow up | Stent group: 90.5% <br>PCTA 76.1%, p=0.016 | Non-significant primary outcome |
| Minimal luminal diameter | Stent group: 1.69 +/-0.52mm <br>Control group 1.57 +/-0.44mm, p=0.096 | ||||
| A randomized comparison of a sirolimus-eluting stent with a standard stent for coronary revascularization. Morice MC, Serruys PW, Sousa JE et al. 2002 | 120 patients with a single coronary lesion up to 18mm long were randomly assigned to receive the sirolimus-eluting stent, and 118 were assigned to receive the standard stent. Angiographic follow up at 6 months, clinical follow up for 12 months |
Double blind RCT | In stent stenosis >50% | Eluting Stent group: 0%<br>Control group: 26.6%, p<0.001 | High control stenosis rate |
| Major cardiac events | Eluting Stent group: 5.8%<br>Control group 28.8%, p<0.001 | ||||
| First clinical experience with a paclitaxel derivate-eluting polymer stent system implantation for in-stent restenosis: immediate and long-term clinical and angiographic outcome. Liistro F, Stankovic G, Di Mario C, et al. 2002, Italy | Fifteen consecutive patients with elective indication for PTCA for in-stent restenosis were treated with the QuaDS-QP2 stent implantation (taxol) | Angiography at 6 months | Restenosis of 2 vessels at 6 months<br>Mean lumen loss 0.47% +/-1.01mm | ||
| Angiography at 12 months | 8 of 13 patients (61.5%) had angiographic restenosis (late loss 1.36 +/-0.94mm) | ||||
| Complications | 1 post procedural MI (NQWMI)<br>1 MI 2 months post stent insertion | ||||
| A paclitaxel-eluting stent for the prevention of coronary restenosis. Park SJ, Shim WH, Ho DS, et al. 2003, South Korea | 177 patients with discrete coronary lesions, randomised to paclitaxel-eluting stents (low dose n=59, or high dose n=60,) or control stents n=58 (15mm long) Pts all had 1-2 vessel disease Angiography at 6 months |
'triple blind ' RCT | Percentage luminal loss | High dose: 14 +/-21%<br>Low dose: 23 +/-25%<br>Control group 39 +/-27%, p<0.001 | |
| Percentage restenosis | High Dose 4%<br>Low dose 12%<br>Control 27% | ||||
| Two-year angiographic and intravascular ultrasound follow-up after implantation of sirolimus-eluting stents in human coronary arteries. Sousa JE, Costa MA, Sousa AG, et al. 2003 Brazil | 30 patients treated with sirolimus-eluting Bx Velocity stenting (slow release, n=15, and fast release, n=15) (not randomised) Angiographic and intravascular USS findings at 2 years |
2 arm cohort study | In-stent lumen loss at 2 years | Slow release group 0.28+/-0.4 mm<br>Fast release group 0.09 +/-0.23mm, P=0.007 | Small study Data on patient that had an MI not included |
| Stenosis requiring re-intervention | 1 patient in the fast release group had a 52% in-stent stenosis requiring revascularisation | ||||
| Complications | 1 patient had an MI with occlusion of a stented vessel, precluding 2 year angiographic follow up | ||||
| Paclitaxel coating reduces in-stent intimal hyperplasia in human coronary arteries: a serial volumetric intravascular ultrasound analysis from the Asian Paclitaxel-Eluting Stent Clinical Trial ASPECT Hong MK, Mintz GS, Lee CW, et al. 2003, South Korea | 81 patients with single lesions, randomised to high dose paclitaxel-coated stents n=28, low dose paclitaxel stents n=28, and bare metal stents n=25 6 month intravascular ultrasound performed |
'triple blind' RCT | Volume of In-stent lumen loss at 6 months | Control group: 31 +/-22mm3<br>Low dose group 18 +/-15mm3<br>High dose group 13 +/-14mm3, p=0.001 | |
| Complications | 1 case of late malopposition occurred in the high dose group | ||||
| Clinical impact of drug-eluting stents in changing referral practices for coronary surgical revascularization in a tertiary care center. Ferreira AC, Peter AA, Salerno TA, et al. 2003 | 196 consecutive coronary angiograms and medical records of patients referred for coronary bypass surgery were reviewed |
Cohort study | Change in management if 100% stenosis free stents were available | 79% of patients would have still required CABG, 21% would have had stents instead | Single Cardiologist determined change of management Single USA centre |
| Heparin-coated stent placement for the treatment of stenoses in small coronary arteries of symptomatic patients. Haude M, Konorza TF, Kalnins U, et al. 2002, Germany | 588 patients with vessels from 2-2.6mm in size (small coronary arteries), randomised to angioplasty (n=195), bare stenting (n=196), or heparin-coated stenting (n=197). 6 month angiography |
Double blind RCT | Restenosis after 6 months | Restenosis rate was 32.2% after PCTA, 24.8% after bare stenting, 29.6% after heparin-coated stenting, (P=0.34) | 20% of patients refused follow up angiography |
| Complications | 2 stent embolisations during procedure |
Author Commentary:
The two major studies in this area are currently the RAVEL and the ASPECT trials. They report a virtual elimination of in-stent stenosis at 6 months in patients receiving a single sirolimus or paclitaxel eluting stent. Good patency has been demonstrated for upto 2 years. However other studies using taxol or heparin coated stents have not demonstrated significant benefits. More worryingly two further large trials have recently been stopped and no results published. The ACTION trial of actinomycin-D eluting stents was stopped early and Guidant refused to release the early data in 2001.
Then in 2003 Guidant also stopped the DELIVER trial (a paclitaxel-coated stent trial). Thus publication bias is becoming a significant concern in this area with the market for these stents in the USA being worth an estimated $6.5 billion.
However assuming that a failure free stent is found Ferreira et al showed that this would reduce the number of CABG referrals in the USA by around 20-25%.
Then in 2003 Guidant also stopped the DELIVER trial (a paclitaxel-coated stent trial). Thus publication bias is becoming a significant concern in this area with the market for these stents in the USA being worth an estimated $6.5 billion.
However assuming that a failure free stent is found Ferreira et al showed that this would reduce the number of CABG referrals in the USA by around 20-25%.
Bottom Line:
Sirolimus and paclitaxel eluting stents seem to have very good patency in patients treated with mainly single lesions. No studies of CABG vs Drug eluting stents have yet been performed.
References:
- Moer R, Myreng Y, Molstad P, et al.. Stenting in small coronary arteries (SISCA) trial. A randomized comparison between balloon angioplasty and the heparin-coated beStent.
- Morice MC, Serruys PW, Sousa JE et al.. A randomized comparison of a sirolimus-eluting stent with a standard stent for coronary revascularization.
- Liistro F, Stankovic G, Di Mario C, et al.. First clinical experience with a paclitaxel derivate-eluting polymer stent system implantation for in-stent restenosis: immediate and long-term clinical and angiographic outcome.
- Park SJ, Shim WH, Ho DS, et al.. A paclitaxel-eluting stent for the prevention of coronary restenosis.
- Sousa JE, Costa MA, Sousa AG, et al.. Two-year angiographic and intravascular ultrasound follow-up after implantation of sirolimus-eluting stents in human coronary arteries.
- Hong MK, Mintz GS, Lee CW, et al.. Paclitaxel coating reduces in-stent intimal hyperplasia in human coronary arteries: a serial volumetric intravascular ultrasound analysis from the Asian Paclitaxel-Eluting Stent Clinical Trial ASPECT
- Ferreira AC, Peter AA, Salerno TA, et al.. Clinical impact of drug-eluting stents in changing referral practices for coronary surgical revascularization in a tertiary care center.
- Haude M, Konorza TF, Kalnins U, et al.. Heparin-coated stent placement for the treatment of stenoses in small coronary arteries of symptomatic patients.