From bedside to bench and back again: translational studies of mechanical unloading of the left ventricle to promote recovery after acute myocardial infarction [version 1; referees: 2 approved]

Heart failure is a major cause of global morbidity and mortality. Acute myocardial infarction (AMI) is a primary cause of heart failure due in large part to residual myocardial damage despite timely reperfusion therapy. Since the 1970’s, multiple preclinical laboratories have tested whether reducing myocardial oxygen demand with a mechanical support pump can reduce infarct size in AMI. In the past decade, this hypothesis has been studied using contemporary circulatory support pumps. We will review the most recent series of preclinical studies in the field which led to the recently completed Door to Unload ST-segment Elevation Myocardial Infarction (DTU-STEMI) safety and feasibility pilot trial

Mechanical Left Ventricular Unloading to Reduce Infarct Size During Acute Myocardial Infarction: Insight from Preclinical and Clinical Studies

Acute myocardial infarction (AMI) remains a leading cause of morbidity and mortality. Pioneering preclinical work reported by Peter Maroko and Eugene Braunwald in 1971 identified oxygen supply and demand are primary determinants of myocardial infarct size in the setting of a heart attack. Since the 1950s, advances in mechanical engineering led to the development of short-term circulatory support devices that range from pulsatile to continuous flow pumps. The primary objective of these pumps is to reduce native heart work, enhance coronary blood flow, and sustain systemic perfusion. Whether these pumps could reduce myocardial infarct size in the setting of AMI became an intense focus for preclinical investigation with variable animal models, experimental algorithms, and pump platforms being tested. In this review, we discuss the design of these preclinical studies and the evolution of mechanical support platforms and attempt to translate these experimental methods into clinical trials.status: publishe

The Impella Microaxial Flow Catheter Is Safe and Effective for Treatment of Myocarditis Complicated by Cardiogenic Shock: An Analysis From the Global cVAD Registry

BACKGROUND: Myocarditis complicated by cardiogenic shock remains a complex problem. The use of acute mechanical circulatory support devices for cardiogenic shock is growing. We explored the utility of Impella transvalvular microaxial flow catheters in the setting of myocarditis with cardiogenic shock. METHODS AND RESULTS: We retrospectively analyzed data from 21 sites within the cVAD registry, an ongoing multicenter voluntary registry at sites in North America and Europe that have used Impella in patients with myocarditis. Myocarditis was defined by endomyocardial biopsy (n = 11) or by clinical history without angiographic evidence of coronary disease (n = 23). A total of 34 patients received an Impella 2.5, CP, 5.0, or RP device for cardiogenic shock complicating myocarditis. Baseline characteristics included age 42 ± 17 years, left ventricular ejection fraction (LVEF) 18% ± 10%, cardiac index 1.82 ± 0.46 L·min CONCLUSIONS: This is the largest analysis of Impella-supported myocarditis cases to date. The use of Impella appears to be safe and effective in the settings of myocarditis complicated by cardiogenic shock