AHRQ: CABG better than PCI for angina relief and re-intervention
ACCORDING TO a new report by the Agency for Healthcare Research and Quality (AHRQ – part of the US Department of Health and Human Services), patients with mid-range coronary artery disease are more likely to get relief from angina and less likely to have repeat procedures if they receive coronary artery bypass graft (CABG) compared to percutaneous coronary intervention (PCI) with or without a stent The analysis entitled, “Comparative Effectiveness of Percutaneous Coronary Interventions and Coronary Artery Bypass Grafting for Coronary Artery Disease”, drew on 23 randomised controlled trials that compared treatments for patients with mid-range coronary disease treatable with either PCI or CABG. As defined by the report, mid-range disease may occur in three ways: a single blockage of the vital left anterior descending artery, blockage of two arteries or some forms of less-severe blockage of three arteries. The report also found that for mid-range coronary artery disease, bypass surgery and angioplasty patients had about the same survival rates and similar numbers of heart attacks, but that bypass surgery presents a slightly higher risk of stroke within 30 days of the procedure. A summary of the report has been posted in the online version of Annals of Internal Medicine. The new Federal study, funded by AHRQ’s Effective Health Care program and completed by the Agency’s Stanford-UCSF Evidence-based Practice Center, compared the outcomes and risks of the procedures in patients with mid- range coronary disease, where either procedure might be chosen. The review concluded that approximately 84% of patients who undergo CABG are free of angina pain one year after the procedure, compared with about 75% of patients who receive PCI. The difference narrows but remains substantial five years after treatment (PCI-CABG difference in freedom from angina ranged from -5.0 percent to -8.0 percent; PCI/CABG odds ratio ranged from 0.50 to 0.66, p<0.0001 at 1, 3, and 5 years.) In addition, approximately 4% of patients who have CABG undergo a repeat procedure within one year, and 10% within five years. The need is ‘significantly higher’ among patients who receive PCI with 24% more at one year and 33% more at five years. (PCI-CABG difference in freedom from repeat revascularization ranged from -23 to -33 percent, PCI/CABG odds ratios ranged from 0.11 to 0.13; p <0.0001 at 1 and 5 years.). The PCI-CABG difference in freedom from MI was small, less than 1% (PCI/CABG odds ratios ranged from 0.87 to 0.92), between one and five years after the procedure and did not achieve statistical significance at any time point. Moreover, studies that measured patients’ quality of life six months to three years after undergoing the procedures found significantly more improvement for CABG patients than for PCI patients. The difference, which equalizes after three years, was attributed to angina relief. However, the odds of surviving either procedure are high at about 98.5% of patients survive beyond 30 days for both CABG and PCI (with or without a stent) and long-term survival rates are likely to be comparable. About 96% of patients live at least one year following both procedures and 90% live five years or more. The methods of cost determination varied among trials and countries, yet nine of the ten RCTs found that the initially lower cost among PCI-assigned patients narrowed substantially over followup. In medium to long-term followup, PCI-assigned patients had only modestly lower costs (approximately 5%) than CABG-assigned patients. This pattern of progressively narrowing cost differences was evident both in trials employing balloon angioplasty and in trials using coronary stents. The report states that further research is needed to clarify survival benefits for patients at either extreme of the mid-range spectrum. “Choosing a treatment for coronary disease has long been a difficult challenge,” said AHRQ Director Dr Carolyn M Clancy, “But this new evidence-based report provides a vital reference to help doctors, patients, and their families make the best possible decision.”
