In patients being treated for myocardial infarction (MI), complete revascularization of all significantly blocked arteries leads to better outcomes compared to a strategy of unblocking just the "culprit" artery responsible for the infarct, according to a new study presented during a Hot Line session at ESC Congress 2014.

Results of the Complete versus Lesion only PRimary-PCI Trial (CvLPRIT), presented as a congress Hot Line may be practice-changing when considered together with some other recent trials, said study investigator Anthony Gershlick, MD, from University Hospitals of Leicester NHS Trust, Glenfield Hospital, in Leicester, England.

"Until now there have been conflicting data regarding the optimal management of patients who, whilst undergoing primary percutaneous coronary intervention (P-PCI) after myocardial infarction (MI) are also found to have lesions in their non-infarct related artery (N-IRA)," noted Professor Gershlick.

"Current guidelines from ESC and AHA /ACC recommend treating the infarct-related artery (IRA) only, but the results of our study demonstrate a highly significant benefit with a strategy of complete revascularization instead. These findings should suggest strongly that all lesions be treated before the patient is discharged," he added.

CvLPRIT included 296 heart attack patients who presented at seven UK interventional cardiology centers. Prior to treatment with P-PCI the patients were randomized to receive IRA-only revascularization (n=146) or to have complete revascularization of both the IRA as well as all N-IRAs (n=150) that were shown to be significantly blocked.

For patients in the complete revascularization group, the IRA was treated first, followed by the N-IRAs - preferably in the same sitting, but definitely during the same index hospital admission.

The study found that one year after the procedure, patients in the complete revascularization group had significantly better outcomes compared to those who had only their IRA revascularized, based on a composite endpoint of major adverse cardiac events (MACE) including: all-cause mortality, recurrent MI, heart failure and ischemic-driven revascularization. MACE occurred in 21.2% of the IRA-only arm versus 10.0% of the complete revascularization group (hazard ratio [HR] 0.45; p=0.009), and the difference between the two groups was seen early (p=0.055 at 30 days).

Not surprisingly, procedure time and contrast volume load were significantly higher in the complete revascularization group compared to the IRA-only group (55 vs. 41 min., p< 0.0001; and 250 vs. 190 ml, p< 0.0001, respectively), but despite this, the complete revascularization patients had no increase in stroke, major bleeding or contrast-induced nephropathy, said Professor Gershlick.

The CvLPRIT results correlate strongly with those of the earlier Preventive Angioplasty in Myocardial Infarction (PRAMI) Trial, which was presented during last year's ESC Hot Line session.

"The PRAMI trial reported clear clinical benefit in treating both IRA and N-IRAs at the index P-PCI, but there was some criticism of the trial design," said Professor Gershlick. "As a result, PRAMI has not led to widespread changes in clinical practice, with IRA-only revascularization at P-PCI remaining by far the more common practice."

However, he said the results of CvLPRIT reinforce the PRAMI results and strengthen the argument for a strategy of complete revascularization at the time of a patient's index hospital admission.

"The early separation of the curves in CvLPRIT suggests a delayed staged out-patient complete strategy may not be as effective," he added.

The sponsor was the University Hospitals of Leicester NHS Trust. The main study was funded by the British Heart Foundation, with the CMR sub-study supported by the National Institute of Health Research.

Dr. Gershlick reports advisory board/meeting travel assistance/ lecture bureau: Medtronic Corp, Boston Scientific, Abbott vascular, Daiichi Sankyo, Medicines Company.