Single long stent on par with multiple overlapping stents for treating diffuse CAD

Using a single long 48 mm drug-eluting stent (DES) is comparable to two overlapping DES in terms of target lesion failure (TLF) in patients who had diffuse coronary artery disease (CAD) with very long lesions, according to a Singapore study.

“Despite its wide usage [in treating diffuse CAD], overlapping DES poses an increased risk for adverse clinical and angiographic outcome, especially with first-generation DES,” said the researchers led by Dr Joshua Loh from the National University Heart Centre, Singapore. Longer stent, on the other hand, is a known predictor of stent thrombosis, which may be mitigated with newer-generation stent.

As newer-generation stents with better safety profiles are emerging, the researchers sought to compare the outcomes of implantation with the contemporary single long 48 mm Xience Xpedtion DES (SL-DES; n=117) vs two overlapping contemporary DES (OL-DES; n=101) in 218 patients (mean age ~60.6 years, >80 percent male) with very-long CAD. All patients were on dual anti-platelet therapy comprising aspirin + P2Y12 receptor antagonists for at least 12 months after DES implantation. [Cardiovasc Revasc Med 2020;doi:10.1016/j.carrev.2020.02.005]

At 2 years, the primary endpoint of TLF — a composite of target lesion revascularization, target vessel myocardial infarction, and cardiac mortality — occurred at comparable rates among patients who received SL-DES vs OL-DES (5.3 percent vs 6.3 percent; adjusted odds ratio [OR], 1.43, 95 percent confidence interval [CI], 0.50–4.11).

Similarly, there were no significant differences in individual TLF components at 2 years between OL- vs SL-DES: target lesion revascularization (OR, 0.45, 95 percent CI, 0.41–4.98), target vessel myocardial infarction (OR, 0.54, 95 percent CI, 0.10–3.02), and cardiac mortality (OR, 3.03, 95 percent CI, 0.71–13.07).

The time to TLF was also similar between the two groups (p=0.754).

“Our results suggest that both strategies are reasonable treatment options for patients with diffuse CAD,” stated Loh and co-authors.

“The pathophysiologic mechanisms underlying the reduction in stent thrombosis in contemporary DES may be due to more potent antiproliferative agents with better bioavailability and thinner fracture-resistant struts with thromboresistant/bioresorbable polymer,” they explained.

Compared with using two overlapping stents, a single long stent was shown to be more cost effective in a previous study, which has shown less cost, contrast volume, and procedural time required for implantation of a single stent. [Am J Cardiol 2002;90:460-464]

Although the current study did not find significant differences in these aspects between the two strategies, the researchers also noted that the SL-DES group included more patients with longer mean lesion length (p=0.003) and multivessel PCI* (p=0.001) than the OL-DES group. When analysis was restricted to patients with single-vessel PCI, they found that SL-DES indeed required significantly less contrast volume and numerically shorter intervention time.

“Our findings extend current knowledge on the treatment of very-long CAD, but larger randomized controlled trials with longer term follow-up are needed in order to draw a definitive conclusion on the best treatment strategy for diffuse CAD,” suggested Loh and co-authors, who noted that the current study was based on retrospective observational registry data with a small sample size from a single centre.