Talking Tall Rounds®: Rescue from Cardiac Arrest

Podcast Transcript

Announcer:
Welcome to the Talking Tall Rounds Series, brought to you by the Sydell and Arnold Miller Family Heart, Vascular & Thoracic Institute at Cleveland Clinic.

Paul Cremer, MD:
I'm Dr. Paul Cremer. I'm the Associate Director of the Cardiac Intensive Care Unit. It's my privilege to moderate this session on rescue from cardiac arrest. Today, we have a great program, multidisciplinary discussion related to the care of these patients, the medical care, transitions of care, interventional and surgical management. But I think what's going to make this session especially memorable is that we are incorporating a patient testimonial. I'll start by the case, which will be presented by one of our senior cardiology fellows, Dr. Montgomery, who I would also like to just take a moment to thank for everything he's done for our educational opportunities with the fellows during the pandemic. Rob.

Robert Montgomery, MD:
We start with the case from J-31 ICU month, where we saw multiple cardiac arrests, which illustrated the team-based approach and importance of the post-arrest care, and prompt recognition of the underlying cause. We start, not at Cleveland Clinic, in the town of Ravenna, with a 60-year-old man with a history of hypertension, hyperlipidemia, active tobacco use, who presents with sudden onset chest pain at work. EMS is called, and EKG shows an anterior STEMI. On arrival to the local ED, he had a VF arrest, status post prompt recognition and defibrillation times two. A emergency cardiac catheterization showed an LAD occlusion, status post two drug-eluting stents. He is transferred, intubated for post-arrest care. He arrives via MedFlight.

Robert Montgomery, MD:
His initial EKG shows to diffuse Q waves, and a initial surface echo shows apical akinesis with a area of a large anterior MI. The patient remains intubated overnight, with a plan for extubation in the morning. On holding sedation in the morning, the patient becomes diaphoretic, and endorses chest pain, and his EKG shows worsening ST elevations. The outside cath is not available at the time, and so he's taken emergently to our cath lab for ischemic evaluation.

Robert Montgomery, MD:
Our cath shows two patent stents in the LAD, with an open LAD, but there's concern from our interventional cardiologist that his left main coronary artery is much narrower than the rest of his arteries. An intravascular ultrasound is done, showing good stent apposition in the LAD, but evidence of an intramural hematoma of his left main coronary artery. Because of this, and the fact that he just had two stents and is on dual anti-platelet therapy, intra-aortic balloon pump is placed. CTS is consulted for bypass in the setting of likely a iatrogenic intramural hematoma of his left main coronary artery, from his initial PCI. Ticagrelor is stopped. Cangrelor is started, and plan is for a relook cath in 48 hours to evaluate for resolution.

Robert Montgomery, MD:
The relook cardiac catheterization is unchanged, and the patient is taken directly for a four-vessel CABG, with a LIMA to LAD and saphenous vein grafts to the ramus, PDA and acute marginal. The patient has an uneventful postoperative course, and he's discharged on postop day six. He has completed cardiac rehab. He follows at our clinical and preventions center. He's quit smoking, and he started evolocumab for statin intolerance. We are all very grateful for him to actually to be able to be here and share his story.

Grant Reed, MD:
I'm going to follow up with a lot of what we've already talked about today and take a step back and just discuss what is the role in timing of diagnostic angiography, as well as PCI in patients that have cardiac arrest, whether that be due to ST segment elevation MI or due to another mechanism. So just as Dr. Phelan said, it's very important upfront to understand the mechanism of your arrest so that you can treat it most effectively in an ACLS setting. This is a very commonly encountered issue. It's somewhat controversial. It's an issue that we get presented with all the time as interventional cardiologists. Patients that come in post arrest may have an uncertain prognosis, will you take this patient to the cath lab? And it's our job to triage this, work with the providers that are asking as well as the family to come up with the right decision.

Grant Reed, MD:
And really it all comes down to understanding the mechanism of the arrest and what the patient's prognosis is. And the initial EKG pre-arrest can be very helpful as well as the EKG post-arrest. So in patients with ST segment elevation on EKG prior to or after ROSC, those patients should be presumed to have a STEMI. And just as Dr. Bhargava said, they do much better with immediate coronary angiography and revascularization if indicated.

Grant Reed, MD:
Now, there's a subset of patients that may have baseline ST segment elevations, a subset of patients that may have a non-STEMI related reason for a VT/VF arrest. However, we should consider a default pathway that patients that have ST segment elevation on EKG should be taken to the cath lab. Patients that have a VT/VF arrest that do not have ST segment elevation on EKG, you should really strongly consider it.

Grant Reed, MD:
And there's about a third of patients who will have a culprit lesion on a catheterization, despite not having ST segment elevation. These may be patients with a circumflex lesion or maybe something that's just electrically silent. But nonetheless, those are patients that I think there's less ambiguity about. Patients that have an arrest that is not due to VT/VF that do not have ST segment elevation on EKG fall into a "grayer" area. And these are often patients with PEA arrest. And the pathway that we've been following mostly at the Clinic and nationally is to triage patients to a medical or a coronary ICU where they can be further evaluated and decision to proceed with catheterization can then be decided on based on the underlying illness and the presumed cause of arrest.

Grant Reed, MD:
Dr. Bhargava mentioned some favorable resuscitation features. Well, some unfavorable resuscitation features which we consider are those patients with an unwitnessed arrest without bystander CPR, patients that do not have VF as the initial rhythm, have a prolonged period of ROSC, have an elevated lactate or a low pH, which go hand in hand, patients that are old with other major medical co-morbidities. These are patients that we might want to have a pause about because their overall prognosis is actually very poor, no matter what we do.

Grant Reed, MD:
And it's not just one of these features, but it's the overall picture of the patient that is important to consider. As an interventional section, we've actually put a lot of time and effort into forming a guideline that we can use when we're maybe receiving these patients in the middle of the night and trying to decide on what to do. And patients that have at least two unfavorable resuscitation features, we say as a guideline, those are patients which we may decide to triage to the CICU to help figure out, and then take them to the lab if it's evident that ischemia is the cause of their arrest. But a team-based approach is essential. And all those patients that have a VT/VF arrest, we do recommend therapeutic hypothermia as Dr. Rampersad had mentioned.

Grant Reed, MD:
So why do we have these guidelines? And not to go through all of the data here, but I want to highlight the highest quality randomized controlled trial in this area, as well as the meta-analysis that our group just put together on this. So the COACT trial was a randomized controlled trial in this area, very hard to conduct an RCT in this topic, but this is a very well done study. It was well powered to detect outcomes. 552 patients with an out-of-hospital cardiac arrest that did not have ST segment elevation on their EKG upon ROSC. This was a contemporary and generalizable patient population. Actually, about 78% had a witness arrest. They had a relatively reasonable time to ROSC with 15 minutes, and I would argue that's actually better than a lot of patients that we see, and their baseline pH was around 7.2. And here, you can see a very mild troponin elevation.

Grant Reed, MD:
Sometimes this is something which we encounter, where we have patients that have a PAE arrest or an unknown cause for an initial arrest, and have a very mild troponin elevation. What do you do in those patients? Well, this is that patient population. What we found was that only around 15% of patients had unstable coronary lesions on angiography, although up to two-thirds of them had significant coronary disease. So coronary disease is very prevalent in general. You're going to find it. What do you do with it in patients that have an out-of-hospital arrest that you're not convinced that STEMI is the cause? This is a tough decision that we get put in. A table highlighting clinical outcomes, which I'm going to show even better to here in this Kaplan Meier curve, is that there's really no difference through survival at 90 days between those patients who had delayed coronary angiography or immediate coronary angiography.

Grant Reed, MD:
These are patients that underwent catheterization within the first two hours versus later, essentially within a day, sometimes three days or even longer. There was no difference in survival at 90 days, and no difference in neurologic function for this or any of the secondary endpoints. So you can see here is the Kaplan Meier curves are essentially superimposed on one another.

Grant Reed, MD:
So we took those data and actually all of the other smaller RCTs and prospective studies, and did a pooled analysis of this. And this is actually a paper that, that myself, Dr. Kapadia and Dr. Verma, among others, are now publishing in JACC Intervention. This should be coming out soon. So we compared this early diagnostic angiography with intervention, if needed to, non-early, which is in most cases, more than 24 hours. Definition is somewhat heterogenous, but that's about the best that we can pin down.

Grant Reed, MD:
There was no difference in 30-day mortality or neurologic outcomes. And among patients who did have a culprit lesion that actually underwent PCI, there still was no difference in outcome. Again, these are not the STEMIs. These are patients that maybe have an NSTEMI, maybe have a PEA arrest and are found to have a "culprit lesion," or maybe a lesion which we could consider somewhat making contribution to their overall prognosis. But again, no overall difference in mortality and no difference between US or non-US hospitals.

Grant Reed, MD:
So putting it all together, we have a nice algorithm that we use a section, and we've now published, called the ACE Framework for Out-of-Hospital Cardiac Arrests without ST Segment Elevation. We assessed patients based on their cardiac and non-cardiac status for unfavorable resuscitation features.

Grant Reed, MD:
We consult as a team approach with the interventional cardiologists, the CICU team, and the family to define short and long-term goals of care. And then we set expectations. These expectations should be realistic and upfront. We can plan. If these patients need mechanical support, we can plan on that right away. And just knowing that this timing between early and not early angiography, it's unlikely make a difference in those patients without clear STEMI on EKG. So this really just summarizes all of that and just emphasize this is a team-based approach. It's something that we really enjoy taking part of and playing this role in a patient's care. But again, it's ultimately a shared decision between the interventionalist, the CICU team and the patient, with the family serving as a surrogate. Thanks.

Announcer:
Thank you for listening. We hope you enjoyed the podcast. Like what you heard? Visit Tall Rounds online clevelandclinic.org/tallrounds and subscribe for free access to more education on the go.