JACC White Paper Considers PCI for ULMCA

October 13, 2009—In the Journal of the American College of Cardiology (JACC), David E. Kandzari, MD, et al on behalf of the American College of Cardiology Interventional Scientific Council have published a JACC white paper, “Revascularization for Unprotected Left Main Disease: Evolution of the Evidence Basis to Redefine Treatment Standards” (2009;54:1576-1588).

According to the investigators, the American College of Cardiology/American Heart Association/Society for Coronary Angiography and Interventions guidelines do not currently endorse the performance of percutaneous coronary intervention (PCI) as an appropriate alternative to surgical revascularization for patients with unprotected left main coronary artery (ULMCA) disease. However, there have been multiple clinical trials and registries addressing this subject during the current decade. These investigations have been merited by recent improvements in PCI techniques, the advent of drug-eluting stents (DES), increased understanding of the procedural and anatomical challenges involved with complex coronary interventions, and better adjunctive antithrombotic pharmacological therapy. The JACC white paper is a review of the current evidence on ULMCA PCI and proposes future directions in this evolving field.

The investigators noted that contemporary results involving revascularization with DES demonstrate significant advances compared with earlier experiences. They stated, “The results from these individual studies—though varied in trial design, methods, and sample size—are remarkably concordant and challenge current standards for appropriateness of PCI in this specific lesion subset.”

To establish ULMCA PCI as an alternative revascularization strategy to the existing standard of CABG, the investigators stated that the following questions need to be addressed:

- Beyond the issue of relevant trial design and endpoints, what outstanding information must be obtained before treatment guidelines may be advanced and ULMCA PCI should be recommended?
- Are there current existing data that permit us to move forward with accepting ULMCA PCI as an alternative therapy in broad patient populations or more narrowly defined subgroups of patients?
- What nontechnical issues need to be resolved to move this process forward, for example, long-term pharmacological therapy and other aspects of patient management?

In the JACC white paper, the investigators survey the findings from major contemporary studies: MAIN-COMPARE, SYNTAX, ISAR-LEFT MAIN, and DELFT. In Table 1 of the document, the investigators outlined the data of selected DES trials in ULMCA revascularization. Table 2 of the document outlines comparative trials between DES and CABG in ULMCA revascularization. The investigators summarized the successes and shortcomings with DES, the role of anatomic lesion complexity and techniques, stent thrombosis and antiplatelet therapy, postrevascularization surveillance, and applications of risk-score models.

The investigators concluded:
“For selected patient and lesion groups, our present and evolving understanding of ULMCA revascularization with DES supports revisiting PCI as an alternative to bypass surgery beyond existing guidelines that recommend against its performance. This represents an opportunity for a reappraisal of current treatment standards. The implementation of advances in catheter-based technology will help better address remaining technical challenges. The issue is not whether ULMCA PCI can be technically performed, but rather what treatment should be performed and how the relative merits and risks of revascularization strategies can be responsibly translated to patients as part of informed consent.”