Abiomed stock was down more than 20%, to $178.09 per share, by the close of trading after news of the two studies came out of the American Heart Association’s Scientific Sessions 2019 in Philadelphia.
Dr. Seth Bilazarian, Abiomed’s CMO, countered by saying that the company stood by “more robust, previously published, FDA-audited, prospective real-world studies and randomized controlled trials.”
A research team led by Dr. Amit P. Amin at the Washington University School of Medicine in St. Louis found an increased risk of death, bleeding, acute kidney injury and stroke among patients while they were still hospitalized after receiving Impella pumps versus balloon pumps. After statistically adjusting for certain variables, the observational study found a 24% higher risk of death and 34% increased risk of stroke among people receiving Impella pump treatment versus balloon pumps.
The researchers analyzed data from the Premier Healthcare Database involving 48,000 people at 432 U.S. hospitals who underwent a heart stent procedure and required a mechanical assist device to support their heart during the procedure. Among those studied, 10% (4,782 patients) received an Impella pump, while 90% (43,524 patients) received an intra-aortic balloon pump.
“These data are observational, so they can’t prove causation. But they underscore the need for large, randomized clinical trials and prospective registries to better understand and guide the use of cardiac support devices,” Amin said in a news release.
Meanwhile, another team led by Dr. Sanket Dhruva of the UCSF School of Medicine examined National Cardiovascular Data Registry (NCDR) data on people with cardiogenic shock who received treatment from an Impella or an intra-aortic balloon pump (IABP). The abstract said: “In-hospital death and major bleeding rates were significantly greater among patients receiving Impella when compared to IABP.”
Bilazarian at Abiomed criticized the quality of the research.
“This observational, non-FDA audited analysis is fundamentally flawed because it is based on poor quality, retrospective, payer coding data that lumps all indications together and is impossible to properly propensity match. In this data set, a patient walking in for an elective procedure looks the same as a patient in cardiac arrest with cardiogenic shock,” Bilazarian said.
Abiomed last week released a roundup of study results associating the use of Impella pumps improved patient outcomes and reduced costs. For example, a study out of Yale University examined data from the National Inpatient Sample (NIS), finding that percutaneous ventricular assist devices such as the Impella reduced mortality by 58% — and reduced costs.