Author + information
- Lara Reyelt1,
- Michele Esposito1,
- Kevin Morine1,
- Shiva Annamalai1,
- Courtney Bogins1,
- Peter Natov1,
- Hyunji Koo1,
- Richard Karas1 and
- Navin Kapur1
Ischemic heart failure (HF) is a major cause of mortality worldwide. We previously reported that compared to Primary Reperfusion (PR), first reducing myocardial demand with an acute circulatory support device and delaying reperfusion (Primary Unloading; PU ) reduces myocardial damage in acute MI (AMI). Our purpose was to explore long-term outcomes of PU in AMI compared to PR alone.
Animals were randomized into either the control arm (PR) or the intervention arm (PU) protocol (Figure 1A). Both groups were recovered for 28 days. After 28 days, animals underwent cardiac magnetic resonance imaging (CMR) with late gadolinium enhancement (LGE) to quantify final infarct size and repeat cardiac catheterization. Animals were euthanized and infarct size determined using TTC staining.
Out of 14 total animals, 2 animals in the PR group died 6 hours after reperfusion and 12 animals survived to 28 days (PR: n=6; PU: n=6). Compared to PR, LV scar determined by LGE (3.9±3.2 vs 9±3.7%, p=0.03) and anatomic pathology (7.2±4.9 vs 14.9±4.1%, p=0.02) was significantly lower after PU (Figure 1B-C). At 28 days, compared to PR, PU increased cardiac output (4±0.6 vs 2.6±0.2 L/min, p=0.0008) and LV stroke work (3302±586 vs 2308±291 mL.mmHg, p=0.009). Compared to PR, 28 days after AMI, circulating brain natriuretic peptide (BNP) levels were lower after PU (Figure 1D).
Primary Unloading reduces LV scar, improves LV function, limits indices of maladaptive cardiac remodeling and circulating BNP levels 28 days after AMI. Studies exploring Primary Unloading as an approach to limit ischemic HF are required.
OTHER: Pre-Clinical/First In-Human Studies