NEW YORK (Reuters Health) – Outcomes of percutaneous coronary intervention are just as good when a loading dose of clopidogrel is given in the cath lab just before the procedure as when the loading dose is given 4 to 8 hours beforehand, an Italian group reports.
Dr. Germano Di Sciascio of the University of Rome and colleagues note in the August 10th issue of the Journal of the American College of Cardiology that clopidogrel pre-treatment significantly improves outcome in patients undergoing PCI.
In many centers, they elaborate, patients being evaluated for the need for PCI are preloaded with clopidogrel before undergoing coronary angiography and subsequent angioplasty as necessary. Other centers complete the diagnostic angiography first, “assess the indication for PCI (vs. coronary bypass or medical therapy), and then administer clopidogrel in the laboratory before intervention.”
While the former strategy might unnecessarily increase bleeding risks in patients, it’s not clear that the latter strategy provides an adequate antiplatelet effect compared with pre-treatment given several hours before the procedure.
Dr. Di Sciascio’s team performed a randomized, controlled trial comparing the safety and effectiveness of a 600-mg clopidogrel loading dose given in the cath lab after angiography but before PCI versus routine 600-mg pre-loading given 4 to 8 hours before the procedure.
The study enrolled 409 patients with a variety of ischemic coronary syndromes, including non–ST-segment elevation acute coronary syndrome (NSTE-ACS), but excluding patients undergoing primary PCI for acute MI and ACS patients with high-risk features.
The primary outcome — the 30-day incidence of major adverse cardiac events (cardiac death, MI, or unplanned target vessel revascularization) — occurred in 8.8% (18 of 205 patients) in the in-lab arm versus 10.3% (21 of 204 patients) in the pre-load arm (p=0.72), the researchers report.
A subgroup analysis also showed no significant difference in MACE occurrence in patients with ACS in the two treatment arms: 12 of 73 (16%) in the in-lab group, compared with 9 of 87 (10%) in the pre-load group (p=0.36).
In an editorial, Dr. Goran Stankovic and Dr. Milorad Zivkovic of the Medical School of Belgrade, Serbia argue that the post hoc nature of the subgroup analysis means that “further studies are needed before concluding that in-lab clopidogrel administration is adequate in all cases regardless of clinical presentation.”
Reference:
Effectiveness of In-Laboratory High-Dose Clopidogrel Loading Versus Routine Pre-Load in Patients Undergoing Percutaneous Coronary Intervention: Results of the ARMYDA-5 PRELOAD (Antiplatelet therapy for Reduction of MYocardial Damage during Angioplasty) Randomized Trial
J Am Coll Cardiol 2010; 56:550–557.
