Revascularization Strategies for Multivessel CAD with Impella® for AMI Shock

Bill O’Neill, MD, discusses “Multi- Versus Culprit-Vessel Percutaneous Coronary Intervention in Cardiogenic Shock,” a paper recently published in JACC: Cardiovascular Interventions by Dr. Alejandro Lemor, Dr. O’Neill, and colleagues.

Dr. O’Neill explains that for many years, interventions in acute myocardial infarction (AMI) and AMI cardiogenic shock focused only on the culprit vessel. Then data began to emerge from non-shock patients that multivessel procedures and complete revascularization improved outcomes. CULPRIT-SHOCK data, however, “threw a wrench” in the thinking. “Counterintuitively, what they found was that the patients that had multivessel procedures actually had a worse outcome. They had a higher 30-day mortality, and a higher need for renal replacement therapy, hemodialysis,” O’Neill explains. “But in the CULPRIT-SHOCK trial… only a very small proportion of the patients had hemodynamic support. We wanted to look whether or not the same applied in patients that were supported with the Impella® heart pump in cardiogenic shock.”

O’Neill describes a trend toward higher survival without increasing contrast nephropathy in the National Cardiogenic Shock Initiative (NCSI) study database patients who were treated with multivessel intervention. NCSI best practices include initiating hemodynamic support with Impella prior to PCI, a strategy associated with a significant improvement in survival. “We know now from our own data and from data from others, that Impella actually supports the kidneys almost as much as it supports the heart. And so, it decreases the chance of contrast nephropathy. So, in contradistinction to CULPRIT-SHOCK, where they had a higher increase in nephropathy, we didn’t see any increase in nephropathy in our patients.”

O’Neill emphasizes, “In patients with acute MI shock, if you need to do multivessel intervention, it’s safe to do so.” However, he notes the need to be “judicious in the kinds of occlusions that we’re going after. If they’re definite fresh occlusions, we have to revascularize them. But I think in CTOs, those patients, there’s really no reason to do those and I think that if we wait on those, and do them on a more elective basis, you’re likely to get a better outcome.”

Dr. O’Neill discusses specific patient demographics and procedural characteristics from the paper. Notably, he describes a new insight gained from the data. “These patients have a high prevalence of thrombus because they’re not getting adequate anti-platelet therapy. And if you do multivessel procedures, you’re probably going to have a significant component of distal microembolization. And so, if you microembolize a section of the heart that’s not infarcted but contracting, that part is going to have transient left ventricular dysfunction.” This, he explains, is why hemodynamic support is so important and why this data can’t be compared to CULPRIT-SHOCK data, “because without hemodynamic support, I think that it probably is very risky to do multivessel interventions in shock.”

O’Neill notes that while in other trials and registries, patients with single-vessel disease have higher survival than patients with multivessel disease, “we’ve actually found now that we kind of have about the same survival, so you’ve taken extent of vessel disease out of the equation when you treat the patients with hemodynamic support.” He therefore concludes, “It’s perfectly fine to do prudent multivessel intervention in the setting of support with Impella and in the setting of effective anti-platelet therapy.”