OCTOPUS: Combo of BMS Plus Paclitaxel Balloon Appears Safe But May Be Outdated

The combination of a BMS and postdilation with a drug-coated balloon (DCB) permits strut coverage and protects against focal restenosis as well as does an EES at 6 months. But the combination strategy was associated with more neointimal proliferation in an imaging study published online November 4, 2014, ahead of print in Circulation: Cardiovascular Interventions.

Moreover, in an email with TCTMD, study co-author Bruno Scheller, MD, of the University of Saarland (Homburg, Germany), said this strategy was supplanted by use of DCB alone in subsequent studies and is no longer recommended.Take Home: OCTOPUS: Combo of BMS Plus Paclitaxel Balloon Appears Safe But May Be Outdated

Main findings from the OCTOPUS study were originally presented at the European Society of Cardiology Congress in Munich, Germany, in August 2012.

Investigators led by Sylvia Otto, MD, of University Hospital of Jena (Jena, Germany), randomized 90 patients with 105 lesions scheduled for elective PCI to the everolimus-eluting Xience V stent (Abbott Vascular) or the Coroflex Blue BMS postdilated with the paclitaxel-eluting SeQuent Please balloon (both B. Braun Melsungen, Melsungen, Germany). Nine patients received both the BMS/DCB duo and EES.

Clinical characteristics were similar between the 2 groups except for a lower mean glomerular filtration rate and a trend toward higher LDL cholesterol in the BMS+DCB arm. Stent diameters were well balanced between the groups, and most lesions were fairly complex.

Strut Coverage Suggests Safety

At 6 months, 193.9 struts in the DES group and 219.1 in the BMS+DCB group underwent QCA and OCT imaging. Overall, sufficient strut coverage was observed in both groups, with no difference in the percentage of uncovered struts, meeting the criterion for noninferiority (P = .040) in both per-protocol and intention-to-treat analyses. Moreover, no clusters of incomplete strut apposition were seen in either group. As a result, dual antiplatelet therapy was discontinued at 6 months.

Imaging showed higher percentage stenosis and lower minimal lumen diameter (MLD) in the BMS+DCB group vs the EES group. No differences were seen in uncovered struts or focal in-stent stenosis, but global neointimal proliferation was higher in the BMS+DCB group (table 1).

 Table 1. Imaging Metrics at 6 Months

Two vascular access site complications occurred in the BMS+DCB group, 1 requiring surgical revision of a hematoma. Rates of MACE (death, MI, or TLR) were similar between the BMS+DCB and EES groups at 6 months (9.8% vs 10.4%; P = .919), and there remained no difference at 2 years according to longer-term follow-up results presented at the American College of Cardiology/i2 Scientific Session in March 2014. At the later time point, TLR rates stood at 1.9% and 3.9%, respectively; 2 noncardiovascular deaths occurred in the BMS+DCB group and none in the EES group.

The authors caution, however, that the study was underpowered to show differences in clinical endpoints.

Noting the higher revascularization rates in patients receiving DCB+BMS compared with sirolimus-eluting stents in the PEPCAD III trial, the investigators observe that in the current study BMS were systematically postdilated with a safety margin of a 2.0-2.5 mm larger balloon to avoid geographic mismatch and prevent edge stenosis.

Although the net luminal gain was smaller and neointimal proliferation volume higher in the BMS+DCB group, the neointimal growth appeared diffuse, with no areas of focal stenosis, Dr. Otto and colleagues point out. Whether this might translate into significant in-stent restenosis at a later stage remains unknown, they add.

The investigators note that although DES more potently inhibit neointimal growth than do DCB, the former are subject to late catch-up, likely due to polymer-linked development of in-stent neoatherosclerosis. In contrast, DCB are polymer-free.

Six-Months of Dual Antiplatelet Therapy Okay

Given the association between incomplete strut endothelialization and stent thrombosis, the finding that stents were largely covered at 6 months favors shorter dual antiplatelet therapy, Dr. Otto and colleagues say.

In his email, Dr. Scheller said the results show that sequential use of a BMS and a DCB in the same lesion is safe and provides outcomes comparable to those of first-generation DES.

But Robert S. Schwartz, MD, of the Minneapolis Heart Institute Foundation (Minneapolis, MN), suggested to TCTMD in an email that deploying a DCB first has the advantage of coating the entire artery wall, theoretically providing a better antirestenotic effect after the stent has been placed. He added that when BMS implantation is followed by a DCB—as in this study—not only may portions of the artery not receive sufficient drug but also drug crystals that impinge on the stent will likely embolize with the rest of the DCB agent.

Regardless of the sequence, Drs. Scheller and Schwartz agreed that the results obtained with the SeQuent Please balloon do not represent a class effect of DCBs.

Going It Alone With the DCB

After the original OCTOPUS trial, Dr. Scheller said, the researchers proposed a DCB-only strategy to leverage the unique feature of the DCB concept, which is to “leave nothing behind.”

This approach requires careful lesion preparation, he explained, after which the operator can decide whether to proceed with a stand-alone DCB if the angiographic result is acceptable or to use a stent or scaffold in case of flow-limiting dissection or a residual stenosis greater than 30%. This strategy has been found to be successful in 2 large registries and the randomized BELLO study in small vessels, he added.

“Meanwhile, we discourage use of a BMS and a DCB in the same lesion, as in OCTOPUS I,” Dr. Scheller said. “Instead, we recommend use of a limus DES for bailout situations after DCB-only.”

He noted that early results of the OCTOPUS II study investigating the DCB-only strategy for coronary de novo disease were presented in late 2014 at the Transcatheter Cardiovascular Therapeutics meeting and the American Heart Association Scientific Sessions. The key findings were that fractional flow reserve–guided use of only DCB is feasible in the majority of lesions and is associated with vascular restoration and lumen enlargement at 6 months, resulting in a similar vessel lumen compared with EES, he reported.

Dr. Schwartz called these recent results “very intriguing.” However, he noted, “the problems of acute thrombosis and dissection are still a concern because of the catastrophic potential consequences, with emergent conversion to stenting.” In the coronary arteries, use of a DCB alone remains unproven with regard to both antirestenotic and antithrombotic effect, he added.

 


Sources:
1. Poerner TC, Otto S, Gassdorf J, et al. Stent coverage and neointimal proliferation in bare metal stents postdilated with a paclitaxel-eluting balloon versus everolimus-eluting stents: prospective randomized study using optical coherence tomography at 6-month follow-up. Circ Cardiovasc Interv. 2014;Epub ahead of print.
2. Poerner TC. Feasibility and angiographic six-month follow-up of fractional flow reserve-guided coronary angioplasty using paclitaxel-coated balloons without stent implantation (OCTOPUS II Study). Presented at: American Heart Association Scientific Sessions; November 2014; Chicago, IL.

Disclosures:

 

  • Dr. Otto reports no relevant conflicts of interest.
  • Dr. Scheller reports receiving lecture fees and travel support from B. Braun Melsungen.
  • Dr. Schwartz reports serving as a consultant for Covidien.

 

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OCTOPUS: Combo of BMS Plus Paclitaxel Balloon Appears Safe But May Be Outdated

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