Society news page: Do the Current ACC/AHA guidelines correctly reflect the attitudes and utilization of PCI in patients with unprotected left main coronary artery stenosis?

Comparison of bypass surgery with drug-eluting stents in diabetic patients with left main coronary stenosis

PURPOSE

Several studies have compared the effects of coronary stenting and coronary- artery bypass grafting (CABG) on left main coronary artery (LMCA) disease. However, there are limited data on the long-term outcomes of these two interventions in diabetic patients.

MATERIALS AND METHODS

We evaluated 56 patients with LMCA stenosis who underwent drug-eluting stent (DES) implantation and 116 patients who underwent CABG in a single hospital in China between January 2004 and December 2006. We compared long-term major adverse cardiac events (death; a "serious outcome" composite of death, myocardial infarction, or stroke; and target-vessel revascularization).

RESULTS

In-hospital (30-day) mortality was 0% for the DES group and 3.4% for the CABG group (p=0.31). There was no difference between the two groups in terms of risk of death [hazard ratio for stenting group, 0.49; 95% confidence interval (CI), 0.13-1.63; p=0.55] or risk of serious outcome (hazard ratio for DES group, 1.11; 95% CI, 0.39-1.45; p=0.47). The target-vessel revascularization rate was higher in the DES group than in the CABG group (hazard ratio, 3.67; 95% CI, 1.24-11.06; p=0.018).

CONCLUSION

In this cohort of diabetic patients with LMCA stenosis, there was no difference in composite endpoints between patients receiving DESs and those undergoing CABG. However, stenting was associated with higher rates of target-vessel revascularization than CABG. DES implantation in diabetic patients with LMCA disease was found to be at least as safe as CABG.

Results of percutaneous coronary intervention of the unprotected left main coronary artery in 143 patients and comparison of 30-day mortality to results of coronary artery bypass grafting

Percutaneous coronary intervention (PCI) of the unprotected left main coronary artery (LMCA) is controversial. In 143 patients who underwent PCI of the unprotected LMCA, 30-day mortality was compared with predicted cumulative risk-adjusted perioperative surgical mortality based on logistic European System for Cardiac Operative Risk Evaluation. One-year clinical follow-up was completed in all patients. The overall major adverse cardiac event rate at 1 year was 34.3%, reflecting the high-risk profile of the patient population. Twelve patients (8%) experienced an acute myocardial infarction and 16 (11%) underwent target lesion revascularization. In 31 patients (22%) who died during the first year, median logistic European System for Cardiac Operative Risk Evaluation was 30%. Calculated RRs showed significantly lower 30-day mortality using PCI compared with predicted surgical mortality (RR 0.54, 95% confidence interval 0.31 to 0.86). Angiographic follow-up in 90 of the 118 patients alive at 6 months showed binary restenosis of 6% in patients treated with drug-eluting stents versus 29% in patients receiving bare-metal stents (p < or =0.01). In conclusion, PCI for unprotected LMCA disease was associated with acceptable short- and medium-term outcomes in patients at low to intermediate risk of bypass surgery. Mortality remains high in very high-risk patients unsuitable for surgery. However, in selected indications, PCI of the LMCA can offer an alternative to surgery, especially when using drug-eluting stents.

Serial Angiographic Follow-Up of Sirolimus-Eluting Stents for Unprotected Left Main Coronary Artery Revascularization

OBJECTIVES

This study was performed to evaluate the clinical and serial angiographic outcomes of patients undergoing sirolimus-eluting stent (SES) implantation for unprotected left main coronary artery (LMCA) stenosis.

BACKGROUND

The efficacy of SES has led to their expanded use for off-label indications, including LMCA disease.

METHODS

Unprotected LMCA intervention with SES was attempted in 50 patients. Surveillance angiography was performed at three and nine months' follow-up.

RESULTS

The target lesion involved the distal LMCA in 47 patients (94%). In-lesion restenosis occurred in 21 patients (42%), was focal in 85% of cases, and in 82% involved the branch ostia, sparing the LMCA itself. Target lesion revascularization (TLR) occurred in 19 patients (38%) over a mean follow-up of 276 +/- 57 days; TLR was ischemia-driven in 7 patients (14%). Late loss was significantly greater within the left circumflex (LCX) ostium compared to the parent vessel (PV) of the LMCA bifurcation (0.83 +/- 0.89 mm vs. 0.49 +/- 0.72 mm, p = 0.04). Late loss continued to increase between three- and nine-month follow-up. Final minimal luminal diameter and maximal balloon pressure were independent predictors of restenosis of the PV.

CONCLUSIONS

Restenosis is a frequent finding when serial angiographic follow-up is performed after SES implantation for unprotected distal LMCA lesions. Restenosis is usually focal, most often involves the LCX ostium, and often occurs without symptoms.

Trends in percutaneous versus surgical revascularization of unprotected left main coronary stenosis in the drug-eluting stent era—a report from the American College of Cardiology-National Cardiovascular data registry (ACC-NCDR)

OBJECTIVES

We sought to determine how practice patterns for unprotected left main stenosis have changed with the advent of drug-eluting stents (DES).

BACKGROUND

Percutaneous coronary intervention (PCI) of unprotected left main coronary stenosis has been controversial.

METHODS

We analyzed data submitted to the American College of Cardiology-National Cardiovascular Data Registry (ACC-NCDR) between January 1, 2002 and December 31, 2004 from 1,276,582 cardiac catheterizations at 417 institutions. Of these, 53,548 (4.2%) had left main stenosis >50% and no prior CABG. After excluding the unrevascularized, the patient sample (N = 32,562) was analyzed for PCI vs. CABG. Data was stratified by year/quarter, bare metal stent vs. DES, elective vs. urgent/emergent situations, LVEF < or > or =40%, and %left main and RCA stenosis.

RESULTS

Of unprotected left main revascularizations from 2002 to 2004, PCI increased from 17.0% to 21.9%, while CABG decreased from 83.0% to 78.1% (P < 0.0001). In 2002, bare metal stents were used for all PCIs; in 2004, bare metal stent use was only 25.5%, while DES use was 74.5% (P < 0.0001). Of elective procedures, PCI rose from 19.1% to 27.5% while CABG fell from 80.9% to 72.5% (P < 0.0001). Similar trends, all significant, were seen in every clinical situation.

CONCLUSIONS

In the era of DES, the rate of PCI for unprotected left main stenosis has risen, while CABG has declined. These findings are seen across varying clinical situations, including elective procedures. DES have rapidly and largely replaced bare metal stents for PCI of unprotected left mains. However, PCI is still chosen less frequently than CABG for unprotected left main revascularization.