Erik Swain, editor for Healio, reported on the research presented at the Transcatheter Cardiovascular Therapeutics (TCT) 2022 Conference in Boston. He recounted that in patients with intermediate- and high-risk pulmonary embolism (PE), mechanical thrombectomy was safe and linked with good short-term hemodynamic and clinical outcomes, according to data from the FLASH registry.
The cohort included 800 U.S. patients with PE (mean age, 61 years; 54% men; 76.7% intermediate-risk), of whom 32.1% had contraindications for thrombolysis. All underwent mechanical thrombectomy with the FlowTriever System, Inari Medical, that extracts PE thrombus by aspiration or mechanical modes without need for thrombolytics. McGowan Institute for Regenerative Medicine affiliated faculty member Catalin Toma, MD (pictured), assistant professor of medicine at the University of Pittsburgh School of Medicine and director of interventional cardiology at the UPMC Heart and Vascular Institute, reported new data from the FLASH registry at a press conference at TCT 2022. The results were simultaneously published in Eurointervention.
“Mortality remains high in the PE space, up to 10% at 30 days in recent registries,” Dr. Toma said at the press conference. “Perhaps what’s less appreciated is the comorbidity these patients have with readmission rates, and up to 50% are still having symptoms at 6 months after their acute PE. The current guidelines don’t put a lot of emphasis on advanced therapies; they are reserved for patients who … have a contraindication to lytics or failed therapy. The problem with the lytic approach upfront is the risk of bleeding and the requirement for ICU stay. The mechanical thrombectomy approach can provide rapid resolution of the clot and improvement in hemodynamics without the risk of bleeding.”
The primary major adverse event endpoint — device-related death at 48 hours, major bleeding at 48 hours, and intraprocedural device- or procedure-related events — occurred in 1.8% of patients, Dr. Toma said, noting there were no deaths, 11 major bleeds, and three intraprocedural device- or procedure-related events.
The rates of all-cause mortality were 0.3% at 48 hours, 0.8% at 30 days, and 5% at 6 months, he said.
The 30-day mortality rate was far lower than that observed in the PERT Consortium Quality Database and in a meta-analysis of catheter-directed thrombolysis studies, Dr. Toma said.
He added the rates of 30-day readmission were 6.2% for any cause, 1.4% for something related to the PE treatment, and 4.8% for something unrelated to the PE treatment. This was far lower than that observed in the PERT Consortium, he said.
During the procedure, pulmonary artery pressure dropped a mean of 7.6 mm Hg, or 23% (P < .0001), while cardiac index increased by a mean of 0.3 L/min/m2, or 18.9% (P < .0001), according to the researchers.
More than half (62.6%) of patients required no overnight ICU stay.
At 48 hours, the right ventricle/left ventricle ratio on echocardiography declined from 1.23 to 0.98 (P < .0001), and the improvement continued through mean latest follow-up of 105.2 to 116.3 days, according to the researchers.
The percentage of patients with severe dyspnea dropped from 66.5% at baseline to 15.6% at 48 hours, Dr. Toma and colleagues found.
“The FLASH registry demonstrates the excellent safety profile of the FlowTriever System in a real-world PE population,” Dr. Toma said at a press conference. “These are patients who based on their baseline characteristics have high risk. Nevertheless, mortality remained less than 1% at the 30-day visit. Most importantly, hemodynamics improved rapidly during the procedure and clinical recovery continued for 6 months.”
Randomized controlled trials, including PEERLESS, are planned, he said.
Mr. Swain is a medical journalist and editor. He received his AB in Politics from Princeton University in 1993. Mr. Swain has been in medical publishing since 2013. He is currently Executive Editor of Healio Cardiology and Cardiology Today. Over the course of his career, he has covered, in addition to the clinical side, the business, manufacturing, packaging, R&D and regulatory aspects of health care.
Abstract (Acute Outcomes for the Full US Cohort of the FLASH Mechanical Thrombectomy Registry in Pulmonary Embolism. Catalin Toma, MD; Wissam A. Jaber, MD; Mitchell D. Weinberg, MD, MBA; Matthew C. Bunte, MD, MS; Sameer Khandhar, MD; Brian Stegman, MD; Sreedevi Gondi, MD; Jeffrey Chambers, MD; Rohit Amin, MD; Daniel A. Leung, MD; Herman Kado, MD; Michael A. Brown, MD; Michael G. Sarosi, MD; Ambarish P. Bhat, MD; Jordan Castle, MD; Michael Savin, MD; Gary Siskin, MD; Michael Rosenberg, MD; Christina Fanola, MD, MSc; James M. Horowitz, MD; Jeffrey S. Pollak, MD. EuroIntervention, 2022; 17:1-1, published 09/2022.)