Information for Physicians: Medical Office Review of Dhruva et al.

The Abiomed Medical Office has reviewed the Dhruva et al. paper and supplement analyzing CATH PCI and Chest Pain registry data published in JAMA. This paper has similar conclusions to Dr. Dhruva’s presentation on this same topic in November 2019 at the American Heart Association conference.

Seth Bilazarian, MD, identifies and discusses a number of limitations of this data.

This is a retrospective, observational study.

The IABP AMI CS unadjusted survival rate was 71% – a number not seen in any trial or FDA study.

The analysis excluded IABP patients escalated to other therapies.

The data mixes those who received the Impella® heart pump pre-PCI with those who received Impella as a bailout, rather than isolating the pre-PCI patients from those who had Impella support initiated after the PCI began.

The 16,227 patients who received medical therapy, making up 57.3% of the cohort in this shock population, had a 20% mortality rate, substantially challenging the definition of shock in this data set. Not using inclusion criteria for cardiogenic shock established in multiple RCTs likely explains the low mortality in the medical treatment and IABP arms.

The authors state, “there may be residual confounding whereby patients receiving intravascular microaxial LVADs had greater severity of illness than those receiving IABPs,” which is certainly a limitation that Impella users are familiar with and likely substantially confounds these conclusions.

The authors’ conclusion conflicts with more than 10 years of outcomes data on Impella, which have been reported in more robust, previously published, FDA-audited, peer-reviewed, real-world studies and randomized controlled trials, such as the Inova Study, the NCSI study and the STEMI DTU pilot study.

“Caution is recommended in making important patient management decisions for the patient you may be seeing today when data that conflicts with more than a decade of publications is presented from observational databases,” says Dr. Bilazarian.

Dr. Bilazarian also notes that Abiomed has made a broad commitment to evidence generation for Protected PCI and cardiogenic shock with randomized controlled trials (RCTs) and large real-world data collections. Abiomed is sponsoring the DanGer trial, a large shock RCT in Europe and has recently begun the STEMI-DTU RCT. On February 6, 2020 Abiomed announced the RECOVER IV study, in which patients will be randomized to receive either Impella pre-PCI or other treatment protocols, which can include any kind of non-Impella mechanical circulatory support.

Read the full letter from Dr. Bilazarian here