Meta-Analysis Confirms Superiority of Simple Stenting for Bifurcations

For patients with bifurcation lesions, a simple strategy that involves stenting of the main vessel and provisional treatment of the side branch results in fewer major adverse events than a more complex strategy, researchers conclude in a meta-analysis published online January 4, 2011, ahead of print in Circulation: Cardiovascular Interventions.

Researchers led by Miles W. Behan, DM, of the Golden Jubilee National Hospital (Glasgow, United Kingdom), analyzed patient-level data on 913 subjects from 2 of the largest randomized trials comparing a simple strategy and a systematic 2-stent strategy.

The 2 trials, NORDIC I and BBC ONE, had similar methodology:

• In NORDIC I, 413 patients with a bifurcation lesion were randomly assigned to a simple strategy (stenting of the main vessel with optional stenting of the side branch) or a complex strategy (stenting of both the main vessel and the side branch) using sirolimus-eluting stents. The diameter of the main vessel and side branch were required to be at least 2.5 mm and 2.0 mm, respectively, by visual estimation.
• In BBC ONE, 500 patients with a bifurcation lesion were randomized to a simple strategy (stenting of the main vessel with optional kissing balloon dilatation/T-stent) or a complex strategy (both vessels systematically stented with mandatory kissing balloon dilatation) with paclitaxel-eluting stents. The diameters of the main vessel and side branch were required to be at least 2.5 mm and 2.25 mm, respectively, by visual estimation. Complex strategies included crush, culotte, and T-stenting.

Less Death, MI, TVR with Simple Approach

In the meta-analysis, the simple step-wise provisional T-stenting approach was superior to the complex approach in terms of the composite endpoint (all-cause death, MI, and TVR) at 9 months. Most of this difference was driven by a higher rate of periprocedural MI. The individual endpoints of death, TVR, subsequent MI, or ARC-defined definite stent thrombosis were similar for both groups. However, surgical TVR was significantly higher in the complex group (table 1). Procedure duration, contrast volume, and X-ray dose also favored the simple approach.

Table 1. Endpoints at 9 Months

In subgroup analysis, the simple approach appeared superior for true bifurcations, large diameter side branches, wide-angled bifurcations, longer length side branch lesions, or equivalent-sized vessels (table 2).

Table 2. Subgroup Analysis: Composite Endpoint

Periprocedural MI Important

Dr. Behan and colleagues say the increased rate of periprocedural MI associated with complex procedures probably reflects the longer duration of vessel instrumentation, which involves more dilatation as well as balloon and stent passage. Furthermore, they suggest periprocedural MI may serve as an adverse prognostic indicator.

“We feel that it is important to include periprocedural MI in the composite analysis (this was the case in BBC ONE but not NORDIC I) because of its probable prognostic significance and as a marker of overall uncomplicated clinical success,” they write. “Without the procedural biomarker data, there is no significant difference between the strategies in major endpoints (death, TVR, or non-procedure-related MI), but procedure duration, fluoroscopy time, and contrast volume still favor the simple group.”

Although previous studies have postulated that the complex strategy might confer an advantage in true bifurcations and in certain subgroups such as longer side branch lesions, large-diameter side branches and disease that extends beyond the ostium, the meta-analysis from BBC and NORDIC I clearly shows “no benefit of a complex strategy in these situations, individually or in combination,” the authors conclude.

Unique Approach to Data

In an e-mail communication with TCTMD, Somjot S. Brar, MD, MPH, of Kaiser Permanente (Los Angeles, CA), said the inclusion of some patients without true bifurcation lesions in prior analyses has “clouded the picture” regarding the best treatment strategy. “The authors have shown that the provisional strategy again proves superior in this subgroup,” he said.

Dr. Brar added that analyses using patient-level data can overcome a major shortcoming of traditional meta-analyses: the inability to analyze common subgroups. Full results for all endpoints often are not reported for important subgroups or may be available for some but not all trials.

“Nevertheless, while the subgroup analyses provide new information, they should be interpreted with caution as they are hypothesis generating and may be underpowered,” he said. “Another limitation of patient-level meta-analysis is the inability to include all relevant trials. While several bifurcation trials have been published, this analysis only includes two. These results do not supercede prior meta-analyses but provide complementary and supportive information.”

 

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Source:
Behan MW, Holm NR, Curzen NP, et al. Simple or complex stenting for bifurcation coronary lesions: A patient-level pooled-analysis of the Nordic bifurcation study and the British bifurcation coronary study. Circ Cardiovasc Interv. 2011;Epub ahead of print.

 

 

Related Stories:

• Final Kissing Balloon Unnecessary in Single-Stent Approach to Bifurcation Lesions
• BBC ONE Published: Simple Strategy Best for Bifurcation Lesions
• Two-Stent Strategy Not Advantageous in Bifurcation Lesions