IABP may improve mortality among patients with cardiogenic shock unable to undergo timely PCI

SAN DIEGO — Patients with cardiogenic shock after STEMI who were unable to receive timely PCI had a better rate of in-hospital mortality when treated with an intra-aortic balloon pump compared with no mechanical circulatory support, according to data presented at the Society for Cardiovascular Angiography and Interventions Scientific Sessions.

Among those unable to undergo timely PCI, the in-hospital mortality rate was 34.7% if an intra-aortic balloon pump (IABP) was used compared with 51.6% if a pump was not used (adjusted OR = 0.63; 95% CI, 0.58-0.68). Among those who received timely PCI, the mortality rate was 29.1% with an IABP compared with 23.9% without an IABP (adjusted OR = 1.3; 95% CI, 1.19-1.42).

Shikhar Agarwal, MD, MPH, a cardiology fellow at Cleveland Clinic, noted that the findings in patients who underwent timely PCI are “in sync” with those from the IABP-SHOCK II trial,which demonstrated safety but no reduction in 30-day mortality with IABP in this population. However, “our results have helped carve out a potential niche for the use of IABP for cardiogenic shock patients unable to undergo timely PCI,” he said.

The researchers reviewed data from the Nationwide Inpatient Sample 2003-2012 in order to assess real-world experience and outcomes from the utilization of mechanical circulatory support among patients with cardiogenic shock after STEMI.

“The use of mechanical circulatory support in patients with cardiogenic shock after STEMI is controversial in the current era,” Agarwal said in a press release. “There has been a decrease in the utilization of IABP in the recent years, with a rise in utilization of devices like Impella [Abiomed] and Tandem Heart.”

Overall, there were 414,367 STEMI admissions from 2003 to 2012 (8.7% with cardiogenic shock). Of all STEMI admissions, 9.2% required mechanical circulatory support.

Utilization of IABP increased between 2003 and 2009, but declined steadily in recent years. Although still representing a minority of all cases, the researchers identified a parallel increase in use of percutaneous mechanical circulatory support devices such as the Impella and TandemHeart (CardiacAssist) in the recent years. The incidence of cardiogenic shock also rose significantly over time within the study population. Despite this rise in cardiogenic shock, the proportion of patients with cardiogenic shock who were treated using mechanical circulatory support increased from 48.6% in 2003 to 57.4% in 2009 and declined to 54.7% in 2011. This has been associated with an increase in timely PCI in cardiogenic shock patients, from 35.6% in 2003 to 66% in 2012.

“In this real-world STEMI database, IABP use for cardiogenic shock in STEMI has declined in recent years. On the other hand, there has been a steep increase in the use of percutaneous mechanical circulatory support [devices] such as Impella and TandemHeart in recent years,” Agarwal said. “Among cardiogenic shock patients, IABP use in timely PCI may be harmful rather than beneficial. However, IABP utilization may be particularly useful in reducing short-term mortality among patients unable to undergo timely PCI.”

Reference:

Agarwal S. Best of the Best Abstracts. Presented at: Society for Cardiovascular Angiography and Interventions Scientific Sessions; May 6-9, 2015; San Diego.

Disclosure: Agarwal reports no relevant financial disclosures.