Hospital Outcomes of Patients With Acute Myocardial Infarction-Related Cardiogenic Shock With and Without Revascularization: An Interview With Uwe Zeymer, MD

Dr Uwe Zeymer shares background and insights on his article, "Hospital Outcomes of Patients With Acute Myocardial Infarction-Related Cardiogenic Shock With and Without Revascularization."

My name is Uwe Zeymer, I'm an interventional cardiologist working at the University Hospital in Freiburg. In addition, I'm the vice director of the Institute for MI Research in Ludwigshafen, and I'm a member of the ALKK study group, which is a cooperation of non-university hospitals in Germany. The data we report here comes from this group.

Could you please tell us what inspired your group to conduct this study?

One of my special interests is cardiogenic shock. In this study, we tried to investigate how patients who are admitted to hospital undergoing early invasive strategy do with respect to in-hospital mortality. The special interest was in patients undergoing angiography who had no coronary artery disease (CAD), where you might think, “oh, these are patients who are not that sick compared to patients with real acute myocardial infarction (MI).” And, therefore, for the first time, we were able to report results in a sufficient number of patients who had cardiogenic shock angiography and no CAD.

Your registry analysis found that a significant proportion of patients with acute MI-related cardiogenic shock did not receive percutaneous coronary intervention (PCI). What were the common reasons for withholding PCI in this population?

As you might imagine, we took patients with a suspicion of acute MI—that means elevated troponin and cardiogenic shock—and what we found is that about 80% of patients will undergo PCI, which is reasonable in this context. Only the minority of patients will be referred to coronary artery bypass graft surgery (CABG), but this is less than 1%, and we excluded these patients from our analysis.

There were another 10% of patients having significant CAD who did not undergo PCI. These patients were the elderly, and were often patients (~40%-50%) with prior CABG or with prior PCI. We didn't ask specifically for the reason why they did not undergo PCI, but it might be speculated that these were anatomical reasons, that investigators did not find any culprit lesion or any lesion which could be intervened. There were another 10% of patients without significant CAD, most of them with cardiomyopathy—or another, I think 5%, for example, with Takotsubo—so there were different reasons for having cardiogenic shock, but not CAD. Interestingly, these patients had quite high mortality as well.

Given that patients without significant CAD also exhibited substantial in-hospital mortality—over one-third—how should clinicians adjust their diagnostic strategies when cardiogenic shock is present, but obstructive CAD is not identified on early coronary angiography?

I think there are a number of strategies that should be applied to these patients. First, we have to find out the real cause for shock; it might be not only cardiac but related to sepsis or other reasons, and to rule out this possibility. Second, we should be aware that these patients have a high mortality, so we have to do everything that we can to stabilize these patients, maybe with medication. In some patients, mechanical circulatory support systems might be helpful. But we should not stay there and say, “oh, they don't have CAD, we are fine, they will survive anyway.” This is unfortunately not the case.

Despite guideline recommendations favoring early invasive strategies in these patients, real-world practice often varies. So based on your data, what system-level or clinician-level barriers do you think are delaying or precluding timely revascularization, and what can you do to help close this gap?

What we have found is that age always is somewhat a barrier to early invasive strategy, and severe comorbidities might preclude this patient from an early invasive strategy. I think this barrier should be overcome because we have seen that we can save lives with such a strategy, even in patients who are elderly, above 80 years or so, or who have severe comorbidities. Therefore, I think once the diagnosis of cardiogenic shock has been made, the patient—in most of the cases—should undergo an invasive evaluation if there is CAD or if there is another reason for their instability.

Looking forward, what do you believe are the next steps to improving outcomes in these patients?

That’s the million-dollar question, because, as you know, we have done a lot of trials to improve outcomes, and some of them were neutral. So, I think we have to individualize treatment in this patient population, do the best supportive care that we can, and, in some cases, mechanical circulatory support devices might be helpful. So, we have to learn more about these patients, and I think we need more trials to guide our treatment strategies.

The transcript has been lightly edited for clarity.