Drug-Coated Balloons in STEMI ‘Safe and Feasible’ in Specific Circumstances: REVELATION

PARIS, France—(UPDATED) A small, randomized trial may breathe new life into the concept of using a drug-coated balloon (DCB) instead of a stent in acute MI, particularly in younger patients with specific lesion characteristics, investigators say.

In the REVELATION study, which randomized 120 patients to either a contemporary stent or a DCB, the fractional flow reserve (FFR) value following DCB therapy was noninferior to that following DES at 9 months.

The strategy of “leave no implant behind” may be of particular benefit in younger patients, investigators say. “In young patients, if you need to put in a permanent vascular implant, it stays there for the rest of their life, and there's a chance of in-stent restenosis and stent thrombosis,” Nicola S. Vos, MD (OLVG Hospital, Amsterdam, the Netherlands), the study’s lead author, told TCTMD. “In the future, you always have the possibility to place a stent in the case of stable coronary artery disease or to perform CABG if needed. So, if you can do without a scaffold, especially in a young patient, it leaves open options for the future.”

Vos presented the REVELATION results twice at EuroPCR 2019, first in a late-breaking trial session Tuesday and again in more depth during a special Lancet-sponsored session Thursday. “We believe that lesions of interest are especially focal, soft, non-alcified lesions with an occlusion due to an erosion or rupture of a nonsignificant plaque and especially in the large vessel segments,” she explained. “Patients of interest are especially young patients where the absence of a permanent implant is really [attractive] or patients with at high risk for bleeding or an intolerance for antiplatelet therapy, in which the absence of a permanent vascular implant might abate need for prolonged AP therapy.

Elaborating to TCTMD, she stressed that the strategy is not meant for all lesions or all patients, however. “It’s really important the lesion has specific characteristics. The most essential thing from a lesion characteristic standpoint is that it has to be a nonsevere calcification in a large vessel with an underlying nonsignificant plaque,” she said.

The paper was simultaneously published in JACC: Cardiovascular Interventions.

No Differences in Mean FFR

REVELATION was a single-center study that compared a paclitaxel-coated DCB (Pantera Lux; Biotronik) with contemporary DES (Orsiro; Biotronik or Xience; Abbott).

Patients were randomized to DCB (n = 60) or DES (n = 60) if they had a de novo, non-severely calcified culprit lesion in a native coronary artery with residual stenosis of less than 50% after predilatation. More than 70% of patients had single-vessel disease, and all patients were randomized after predilatation.

The bailout stenting rate in the DCB group was 18% and was most often associated with coronary artery dissection type C or greater.

At 9 months, the DCB group had a mean FFR of 0.92 and the DES group had a mean FFR of 0.91, which confirmed noninferiority with a mean difference of 0.008 (P = 0.27). There were no statistically significant differences between groups for late lumen loss, reference vessel diameter, or minimum lumen diameter at 9 months. Additionally, mean LVEF was 57.1% at 9 months in the DCB group and 58.4% in the DES group (P = 0.38). However, minimum lumen diameter after the index procedure was lower in the DCB group than in the DES group (2.64 vs 2.88; P < 0.01).

According to the researchers, adequate lesion preparation is an important element for maximizing balloon contact area to the vessel wall. They performed thrombus aspiration for visible thrombus and predilatation was performed in all patients in the DCB group.

Although routine thrombus aspiration does not reduce mortality, Vos said during her presentation that in a DCB strategy "you want to optimize the lesion the best you can." Removing as much of the thrombus as possible, she added, may mean that the predilatation can be less aggressive, reducing risk of dissection and bailout stenting, and also helps insure optimal contact of the drug with the vessel wall.

She and her colleagues also note in the paper that adequate attention to balloon inflation—mean time was 64 seconds—“allows a homogeneous and rapid distribution of highly lipophilic paclitaxel into the vessel wall to sustain an antiproliferative effect.”

Other Benefits

While multiple studies have demonstrated good results of DCB versus DES in restenosis and small-vessel disease, data on STEMI patients are limited and nonrandomized, the researchers note. The reason for studying larger vessels in the current trial was because these are typically the ones involve in STEMIs, and are also more likely to include the types of plaques that might be better suited to a DCB approach.

As noted elsewhere at EuroPCR, there is mounting interest in the interventional cardiology community in using plaque characteristics to guide strategy, including the publication of an expert consensus document urging more use of intravascular imaging to help guide treatment decisions.

Alluding to this following Vos’ Thursday presentation, panelist Thomas Lüscher, MD (Imperial College in London, England), cited the EROSION study, in which OCT imaging was used to identify ACS patients with plaque erosion, rather than rupture, who were then treated without a stent. Calling REVELATION a “bold trial,” Lüscher asked Vos if imaging would have “helped” in the trial, especially since plaque erosion is believed to be the cause of one in five acute MIs.

Vos, in response, said, “I completely agree that the underlying mechanism of the acute myocardial infarct is one of the essential things in choosing the right lesions that might benefit from this strategy.

Not Stenting? ‘Nerve-wracking’

Following the Tuesday presentation, panelist Göran Olivecrona, MD, PhD (Lund University, Sweden), noted that 120 patients were recruited over a 3-year period and questioned if some operators had "lack of enthusiasm" to randomize patients like these.

"For interventional cardiologists, it's kind of nerve-wracking to [not do] stenting in these kinds of patients," Vos said. But she added that the strict selection criteria were more likely to blame for the slow enrollment.

Session co-chair Peter F. Ludman, MD (Queen Elizabeth Hospital, Birmingham, England), asked Vos if operators who participated in the trial transitioned to using DCBs in their clinical practice as a result of their experience.

Vos said some are continuing to use it, especially in very young patients with lesions in large vessel segments. Commenting further on this to TCTMD, Vos said, “In the beginning I think we all thought this is kind of weird and nuts to replace a stent with a balloon, because it's not what we are used to doing. But the pilot trial in 2011 convinced us that this was a safe and feasible strategy in specific circumstances. I think it is important to always try new strategies. The current DES are excellent and for many people they are the right way to treat STEMI, but we have to stay curious to see if more individualized treatment is needed in coronary interventions.”

Vos added: "We will do a clinical follow-up out to 5 years. Now we have to think about a bigger trial with more powerful endpoints.”