Drug Elution and Distal Protection in ST-Elevation Myocardial Infarction - DEDICATION: Distal Protection Study

Description:

The goal of the trial was to evaluate distal embolic protection prior to percutaneous coronary intervention (PCI) compared with PCI without embolic protection in native vessels in patients with ST-elevation myocardial infarction (STEMI).

Hypothesis:

Distal embolic protection prior to PCI would be more effective in improving myocardial perfusion than PCI without embolic protection.

Study Design

  • Randomized

Patients Screened: 1,687
Patients Enrolled: 626
Mean Follow Up: 15 months
Mean Patient Age: 62 years
Female: 26%

Patient Populations:

STEMI within 12 hours of symptom onset with total ST-elevation of 4 mm in contiguous leads, age at least 18 years, and occluded or severely stenosed coronary artery without excessive calcification or tortuosity

Exclusions:

Previous MI, left main infarct-related artery, history of gastrointestinal bleeding, pregnancy, renal failure, limited (<1 year) life expectancy, or linguistic problems

Primary Endpoints:

Rate of complete (>70%) ST-segment resolution 90 minutes after PCI detected by continuous ST-segment monitoring

Secondary Endpoints:

Time to >70% ST-segment resolution, maximal cardiac biomarkers, wall motion index by echocardiography at discharge, and major adverse cardiac events

Drug/Procedures Used:

Patients were randomized to distal embolic protection prior to PCI (n = 312) or PCI without embolic protection (n = 314). Patients also received a drug-eluting stent versus bare-metal stent by 2 x 2 factorial design (results presented separately).

Principal Findings:

Patients were well matched with baseline characteristics. In the embolic protection group, 81% received the FilterWire device, 13% received the SpideRx device, and in the remaining patients, distal protection could not be achieved. Initial Thrombolysis In Myocardial Infarction (TIMI) 0 or 1 flow was present in 67% of the embolic protection group and 68% of the PCI alone group. Similarly, visible thrombus was present in 68% and 75%, respectively.

For the primary outcome, complete ST-segment resolution occurred in 76% of the embolic protection group and 72% of the PCI alone group (p = 0.29). There was no difference in the primary outcome among any subgroup tested. There was no difference in the maximum level of creatine-kinase (p = 0.99), troponin T (p = 0.87), or wall motion index (p = 0.35) between the groups. There was also no difference in 30-day major adverse cardiac events (5.4% vs. 3.2%, p = 0.17), respectively for embolic protection versus PCI alone.

At 15 months, definite stent thrombosis had occurred in 2.9% of the embolic protection group versus 0.3% of the PCI alone group (p = 0.02) and target lesion revascularization was 12.5% versus 7% (p = 0.02), respectively.

Interpretation:

Among patients with STEMI, distal embolic protection prior to PCI did not reduce the incidence of complete ST-segment resolution, maximum level of cardiac enzymes, wall motion index, or major adverse cardiac events compared with PCI alone. In fact, there were increased adverse events late in follow-up.

This trial complements the earlier EMERALD trial, which failed to show that GuardWire balloon occlusion improves the myocardial circulation compared with standard PCI alone. These findings are in contradistinction to the recently published TAPAS trial, which revealed that thrombus aspiration by the Export catheter significantly improved myocardial reperfusion.

References:

Kaltoft A, Kelbæk H, Kløvgaardet L, al. Increased rate of stent thrombosis and target lesion revascularization after filter protection in primary percutaneous coronary intervention for ST-segment elevation myocardial infarction: 15-Month Follow-Up of the DEDICATION (Drug Elution and Distal Protection in ST Elevation Myocardial Infarction) Trial. J Am Coll Cardiol 2010;55:867-71.

Presented by Dr. Leif Thuesen at the i2 Summit/American College of Cardiology Annual Scientific Session, New Orleans, LA, March 2007.

Kelbaek H, Terkelsen CJ, Helqvist S, et al. Randomized comparision of distal protection versus conventional treatment in primary percutaneous coronary intervention: The Drug Elution and Distal Protection in ST-Elevation Myocardial Infarction (DEDICATION) Trial. J Am Coll Cardiol 2008;51:899-905.

Keywords: Complement System Proteins, Myocardial Infarction, Follow-Up Studies, Creatine Kinase, Metals, Thrombosis, Drug-Eluting Stents, Balloon Occlusion, Troponin T, Myocardial Reperfusion, Stents, Percutaneous Coronary Intervention


< Back to Listings