Indonersia - For patients with acute ST-segment-elevation MI (STEMI) undergoing PCI of the infarct artery, treating other nonculprit lesions significantly reduces the risk of major adverse cardiovascular events (MACE) . The 65% relative reduction in the MACE risk was driven by a statistically significant reduction in the risk of nonfatal MI and refractory angina, report investigators.
There was a trend toward a reduction in the risk of death from cardiac causes, but the benefit achieved did not reach statistical significance.
"The results of this trial show that in patients with acute STEMI, the use of preventive PCI to treat noninfarct coronary-artery stenosis immediately after PCI in the infarct artery conferred a substantial advantage over not performing this additional procedure," report Dr David Wald (Queen Mary University of London, UK) and colleagues.
The study, known as the Preventive Angioplasty in Acute Myocardial Infarction (PRAMI), was presented today during a hot-line session at the European Society of Cardiology (ESC) 2013 Congress and published simultaneously in the New England Journal of Medicine.
Study Stopped Early for Benefit
Over a six-year period, 465 patients with STEMI from five clinical sites underwent PCI of the infarct-related artery. Of these, 234 patients were randomized to PCI of nonculprit lesions, known as preventive PCI, and 231 patients randomized to a treatment protocol that left these other lesions alone after opening the infarct-related artery. The trial was stopped early in 2013 based on a recommendation from data and safety monitoring committee (DSMB) that noted there was a significant between-group difference in the primary end point favoring preventive PCI.
After a mean follow-up of 23 months, the primary end point, defined as death from cardiac causes, nonfatal MI, or refractory angina, occurred in 21 patients treated with preventive PCI and 53 patients treated with PCI of the culprit lesion only. This translated into a 65% relative reduction in risk and 14% absolute reduction in the primary end point. There was also an observed 68% relative reduction in the risk of nonfatal MI and a 65% reduction in the risk of refractory angina.
PRAMI: Primary End Point and Its Components
|Outcome||Hazard ratio (95% CI)|
|Primary end point (death from cardiac causes, nonfatal MI, or refractory angina)||0.35 (0.21–0.58)|
|Death from cardiac causes or nonfatal MI||0.36 (0.18–0.73)|
|Death from cardiac causes||0.34 (0.11–1.08)|
|Nonfatal MI||0.32 (0.13–0.75)|
|Refractory angina||0.35 (0.18–0.69)|
In an editorial , Dr Laura Mauri (Harvard Clinical Research Institute, Boston, MA) said the strategy of treating nonculprit lesions differs from clinical practice, and current guidelines recommend against treating multiple lesions during STEMI. In the US, the American College of Cardiology/American Heart Association guidelines state that PCI "should not be performed in a noninfarct artery at the time of primary PCI in patients without hemodynamic compromise." The class IIIb recommendation differs slightly from the European Society of Cardiology/European Association for Cardiothoracic Surgery guidelines, which state that with the exception of cardiogenic shock, PCI for STEMI should be limited to the culprit lesion (class IIa, level of evidence B).
In addition, writes Mauri, the COURAGE trial testing a preventive strategy in patients with stable angina failed to show that PCI reduced the risk of death or MI when compared with medical therapy alone. As a result, nonculprit lesions are not treated in the acute setting and are left until symptoms develop. "However, patients who present with STEMI have substantial risk of recurrent early events," she writes. "How do noninfarct lesions confer this risk?"
The answer, she suggests, is that there is no vessel uncompromised in patients presenting with STEMI. "During acute myocardial infarction, there is no healthy vessel, even in cases in which thrombosis is absent," writes Mauri. "We can no longer assume that secondary lesions in acute myocardial infarction are innocent until proven guilty."
heartwire will update this story following the PRAMI presentation at the ESC hot-line session.