This article has been updated with a comment from Abiomed.
The editorial in the journal Circulation said the study’s methodology had several limitations and called for randomized controlled trials (RCTs) to determine the risks of Impella heart pumps. It added, however, that the rapid increase in Impella use and substantial differences in physician practices may have negative implications for patients.
The 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 hospitalized patients after receiving Abiomed’s Impella pumps versus intra-aortic balloon pumps (IABP). 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 should serve as a cautionary note, and we hope that publishing these findings in Circulation will highlight the urgent need for adequately powered RCTs” comparing Impella with balloon pumps and possibly no mechanical support in high-risk patients undergoing percutaneous coronary intervention,” the editorial’s authors wrote. “Until such studies are completed, the current enthusiasm for Impella and the rapid expansion of this technology seem unjustified to the editors.”
Shares in Danvers, Mass.-based Abiomed fell 20% in one day when the study by Amin’s team was published. The stock recovered slightly the following day, but fell again by 13% on Jan. 13 after the company issued revenue guidance that missed Wall Street expectations.
“We agree the Amin paper is an observational analysis with many flaws,” said Dr. Seth Bilazarian, Abiomed’s chief medical officer, in an email to MassDevice. “The PROTECT II randomized controlled trial, which previously published in Circulation, provides a much higher quality source of safety and efficacy data when comparing Impella to IABP.”
Abiomed is forecasting full-year FY 2020 revenue of $846 million to $877 million, which would put it 10% to 14% ahead of the previous fiscal year, but below analysts’ consensus of $885.8 million. The company plans to release third-quarter 2020 financial results on Feb. 6, 2020.