Key outcomes
The procedural success rate, defined as successful stent delivery with less than a 50% residual stenosis and no in-hospital MACE, was 92.4% in Disrupt CAD III, compared to 83.4% for orbital atherectomy in ORBIT II. The primary safety endpoint of freedom from cardiac death, MI, or target vessel revascularization at 30 days was achieved in 92.2% of patients in the intravascular lithotripsy trial, versus 84.4% in ORBIT II.
The 30-day MACE rate of 7.8% in Disrupt CAD III was primarily driven by periprocedural MIs, which occurred in 6.8% of participants. Only one-third of the MIs were clinically relevant by the Society for Coronary Angiography and Intervention definition. There were two cardiac deaths and three cases of stent thrombosis, all of which were associated with known predictors of the complication. There was 1 case each of dissection, abrupt closure, and perforation, but no instances of slow flow or no reflow at the procedure’s end. Transient lithotripsy-induced left ventricular capture occurred in 41% of patients, but they were benign events with no lasting consequences.
The device was able to cross and deliver acoustic pressure wave therapy to 98.2% of lesions. The mean diameter stenosis preprocedure was 65.1%, dropping to 37.2% post lithotripsy, with a final in-stent residual stenosis diameter of 11.9%, with a 1.7-mm acute gain. The average stent expansion at the site of maximum calcification was 102%, with a minimum stent area of 6.5 mm2.
Optical coherence imaging revealed that 67% of treated lesions had circumferential and transmural fractures of both deep and superficial calcium post lithotripsy. Yet outcomes were the same regardless of whether fractures were evident on imaging.
At 30-day follow-up, 72.9% of patients had no angina, up from just 12.6% of participants pre-PCI. Follow-up will continue for 2 years.
Outcomes were similar for the first case done at each participating center and all cases thereafter.
“The ease of use was remarkable,” Dr. Kereiakes recalled. “The learning curve is virtually nonexistent.”
The reaction
At a press conference where Dr. Kereiakes presented the Disrupt CAD III results, discussant Allen Jeremias, MD, said he found the results compelling.
“The success rate is high, I think it’s relatively easy to use, as demonstrated, and I think the results are spectacular,” said Dr. Jeremias, director of interventional cardiology research and associate director of the cardiac catheterization laboratory at St. Francis Hospital in Roslyn, N.Y.
Bruce Jancin/MDedge News
Dr. Allen Jeremias
Cardiologists “really don’t do a good job most of the time” with severely calcified coronary lesions, added Dr. Jeremias, who wasn’t involved in the trial.
“A lot of times these patients have inadequate stent outcomes when we do intravascular imaging. So to do something to try to basically crack the calcium and expand the stent is, I think, critically important in these patients, and this is an amazing technology that accomplishes that,” the cardiologist said.
Juan F. Granada, MD, of Columbia University, New York, who moderated the press conference, said, “Some of the debulking techniques used for calcified stenoses actually require a lot of training, knowledge, experience, and hospital infrastructure.
Dr. Juan Granada
I really think having a technology that is easy to use and familiar to all interventional cardiologists, such as a balloon, could potentially be a disruptive change in our field.”
“It’s an absolute game changer,” agreed Dr. Jeremias.
Dr. Kereiakes reported serving as a consultant to a handful of medical device companies, including Shockwave Medical, which sponsored Disrupt CAD III.
SOURCE: Kereiakes DJ. TCT 2020. Late Breaking Clinical Science session 2.