Use of mechanical circulatory support devices among patients with acute myocardial infarction complicated by cardiogenic shock

Importance: Mechanical circulatory support (MCS) devices, including intravascular microaxial left ventricular assist devices (LVADs) and intra-aortic balloon pumps (IABPs), are used in patients who undergo percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) complicated by cardiogenic shock despite limited evidence of their clinical benefit. Objective: To examine trends in the use of MCS devices among patients who underwent PCI for AMI with cardiogenic shock, hospital-level use variation, and factors associated with use. Design, Setting, and Participants: This cross-sectional study used the CathPCI and Chest Pain-MI Registries of the American College of Cardiology National Cardiovascular Data Registry. Patients who underwent PCI for AMI complicated by cardiogenic shock between October 1, 2015, and December 31, 2017, were identified from both registries. Data were analyzed from October 2018 to August 2020. Exposures: Therapies to provide hemodynamic support were categorized as intravascular microaxial LVAD, IABP, TandemHeart, extracorporeal membrane oxygenation, LVAD, other devices, combined IABP and intravascular microaxial LVAD, combined IABP and other device (defined as TandemHeart, extracorporeal membrane oxygenation, LVAD, or another MCS device), or medical therapy only. Main Outcomes and Measures: Use of MCS devices overall and specific MCS devices, including intravascular microaxial LVAD, at both patient and hospital levels and variables associated with use. Results: Among the 28 304 patients included in the study, the mean (SD) age was 65.4 (12.6) years and 18 968 were men (67.0%). The overall MCS device use was constant from the fourth quarter of 2015 to the fourth quarter of 2017, although use of intravascular microaxial LVADs significantly increased (from 4.1% to 9.8%; P \u3c .001), whereas use of IABPs significantly decreased (from 34.8% to 30.0%; P \u3c .001). A significant hospital-level variation in MCS device use was found. The median (interquartile range [IQR]) proportion of patients who received MCS devices was 42% (30%-54%), and the median proportion of patients who received intravascular microaxial LVADs was 1% (0%-10%). In multivariable analyses, cardiac arrest at first medical contact or during hospitalization (odds ratio [OR], 1.82; 95% CI, 1.58-2.09) and severe left main and/or proximal left anterior descending coronary artery stenosis (OR, 1.36; 95% CI, 1.20-1.54) were patient characteristics that were associated with higher odds of receiving intravascular microaxial LVADs only compared with IABPs only. Conclusions and Relevance: This study found that, among patients who underwent PCI for AMI complicated by cardiogenic shock, overall use of MCS devices was constant, and a 2.5-fold increase in intravascular microaxial LVAD use was found along with a corresponding decrease in IABP use and a significant hospital-level variation in MCS device use. These trends were observed despite limited clinical trial evidence of improved outcomes associated with device use

Strength of Study Evidence Examined by the FDA in Premarket Approval of Cardiovascular Devices

Context Medical devices are common in clinical practice and have important effects on morbidity and mortality, yet there has not been a systematic examination of evidence used by the US Food and Drug Administration (FDA) for device approval. Objectives To study premarket approval (PMA)\u97the most stringent FDA review process\u97of cardiovascular devices and to characterize the type and strength of evidence on which it is based. Data Sources and Study Selection Systematic review of 123 summaries of safety and effectiveness data for 78 PMAs for high-risk cardiovascular devices that received PMA between January 2000 and December 2007. Data Extraction Examination of the methodological characteristics considered essential to minimize confounding and bias, as well as the primary end points of the 123 studies supporting the PMAs. Results Thirty-three of 123 studies (27%) used to support recent FDA approval of cardiovascular devices were randomized and 17 of 123 (14%) were blinded. Fifty-one of 78 PMAs (65%) were based on a single study. One hundred eleven of 213 primary end points (52%) were compared with controls and 34 of 111 controls (31%) were retrospective. One hundred eighty-seven of 213 primary end points (88%) were surrogate measures and 122 of 157 (78%) had a discrepancy between the number of patients enrolled in the study and the number analyzed. Conclusion Premarket approval of cardiovascular devices by the FDA is often based on studies that lack adequate strength and may be prone to bias

Medical device regulation: time to improve performance.

Sanket Dhruva and Rita Redberg comment on a research study evaluating the evidence regarding the performance of device regulatory systems. They argue that adequate funding and increased transparency are vital to future reform