Talking Tall Rounds®: Cutting-Edge Care for HyperAcute Proximal Aortic Dissection

Podcast Transcript

Announcer:

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

Eric Roselli, MD:

Good morning, everyone. I was looking at the curriculum with Katie recently and was surprised to see that we hadn't presented an acute aortic syndrome topic in nearly two years. But during that time we've been really busy taking care of these patients. And although we talk about acute and acute aortic syndrome, it's really these hyperacute patients, the patients that present with ischemia that really demonstrate the multidisciplinary team and the way that we really make a big difference. And so we're going to hear from a host of speakers from different disciplines to present that this morning, leading off with Katie O'Sullivan, who's going to present a really interesting case. Thanks, Katie.

Katie O'Sullivan, MD, PhD:

This is a case of hyper acute type a dissection with visceral and peripheral mild perfusion. And this case demonstrates the importance of swift decision making and a multidisciplinary team approach. So this patient was a 64 year old current smoker without any prior medical history. He presented with sudden onset mid-sternal chest pain, which traveled down to the lower back and his left leg. He also experienced diaphoresis and worrying he was having a heart attack he called an ambulance. On arrival to ED, his pain was ongoing for one hour. On examination, he was diaphoretic, unable to move his left leg. It was pale, pulseless and numb. He was experiencing diarrhea and he had a lactate of 3.2. So he underwent emergent CT aorta. And that CT demonstrated an acute type a dissection with a large entry tear evident here in the distal ascending aorta.

Katie O'Sullivan, MD, PhD:

The arch vessels were coming from the true lumen and were patent. There was aggressive compression of the true lumen of the descending aorta. The celiac trunk and SMA originated from compressed true and false lumens with dissection extending into the ostea. The right renal was from the false, the left from the true. And finally there was an occluded left column iliac artery and approximate left, external ilac artery with reconstitution distally. So two teams worked together with a collaborative approach in the hybrid aorta. The cardiac team opened essentially and cannulated the aorta under TEE guidance and carried out SVC, IVC venous cannulation. And simultaneously, the vascular team undertook a left femoral arterial exposure with insertion of an 8-French reperfusion sheath to enable the dissection repair to continue while the leg was being perfused. So the patient was cooled and after initiation of deep hyperthermic circulatory arrest, an undergrad cerebral profusion, a frozen elephant trunk was carried out.

Katie O'Sullivan, MD, PhD:

And after this, an IVUS of the aorta was carried out from the level of the frozen elephant trunk demonstrating good, true lumen re-expansion throughout the descending aorta, except for that right renal artery, which was still coming off the false lumen. So the postoperative scan here... Sorry, before I go to that. The left common iliac and the external iliac arteries still had severe true lumen compressions. So a series of stents were deployed by vascular surgery thus reestablishing flow down the leg and the femoral arteries repaired with four compartment fasciotomies performed also. So the postoperative scan shows re-expansion of the true lumen. And when we get down distally, you can see that the stents placed were patent also. Now, the patient regained full function of his leg, and he was discharged well on day 13 with a Vac dressing placed on the lateral fasciotomy site. He completed a three month course of coumadin for atrial fibrillation, and he was doing extremely well at his most recent follow-up. Thank you.

Ran Lee, MD:

I'm one of the cardiac intensivists in our cardiac intensive care unit, and I'll be discussing the goals and objectives of initial ICU optimization. As Dr. Roselli had mentioned the Cardiac Intensive Care Unit for these acute cardiac surgery emergencies really becomes a cardio-aortic triage unit where our focus is on very timely and accurate diagnostic acquisition, including but not limited to vital signs, bedside diagnostics, labs, monitoring, medical optimization, and tailoring with treatment and the activation of a multidisciplinary team, which arises at the bedside.

Ran Lee, MD:

We still have to quantify this in piggy backing off of what Dr. Kostura had mentioned about our auto launch system. We have an acute aortic network, which was quantified back in 2014 at the time of 84 hospitals and ERs with immediate distance travel to 40 miles, either by helicopter, fixed wing, or ground ambulance. We saw it at that time to measure time to travel similar to STEMI regional networks of care and extrapolating it to the acute aortic syndrome. Along the way, we sought to leverage information technology systems and be able to rapidly contact multiple stakeholders and transfer images.

Ran Lee, MD:

And right now, the cloud system, which you'll hear a little bit more from Dr. Schoenhagen encompasses greater than 160 centers with the ability to rapidly transfer diagnostic images. This is an example of such cloud-based platform to rapidly contact for an auto launched patient. Dr. Schoenhagen specifically mentioning to us a type A aortic dissection, not only imaging findings to this group, but also pertinent details such as estimated time of arrival. Just a brief overview of acute aortic dissection terminology, we're really focusing in this talk on the hybrid Q-type A aortic dissections, or the type one, or type two debating classifications.

Ran Lee, MD:

And the importance of hyperacute care cannot be more emphasized than this figure from the IRAD registry, really emphasizing the improvement and mortality with prompt surgical management of these acute type A aortic dissections within the first 24 hours as evidenced by the blue curve on top. The goals of hyper acute dissection care really then are timely diagnostics assessment of risk factors for malperfusion, timely stabilization, and timely decision making. This table is from a recent review in JACC from the tail end of 2021, identifying several higher risk features such as pericardial fusion, cardiac tamponade, significant valvular insufficiency, and organ ischemia or mal perfusion as was mentioned in the case at the beginning.

Ran Lee, MD:

So when a patient gets auto launched to the Cardiac Intensive Care Unit, Critical Care Transport, hands off to either the fellow resident, acute care nurse practitioner or staff, really focusing on onset of symptoms, location of symptoms, as well as location on imaging of the tear origination, as well as whatever initial management has been done to date. Then at the bedside, our nursing team really implements protocolized care with bedside vital signs, blood pressures in all four limbs, rapid EKG, lab work, durable IV access. And our providers start to work on arterial line placement if it does not already exist. The cardiology fellow's role is to obtain a quick point of care echocardiogram, really looking at biventricular systolic function, valvular insufficiency specifically focusing on aortic insufficiency, the presence or absence of pericardial effusion, and if necessary repeating CT imaging with dissection protocol, if there are any limitations in outside images.

Ran Lee, MD:

Here's an example of a case from last year. This echo was obtained by one of our first year fellows, really looking at normal biventricular systolic function here and not shown, but in subsequent images, focusing on color Doppler to assess whether or not there's mitral insufficiency or aortic insufficiency. Of note, as you can already see, there's a dilated aortic root and a dissection flap in keeping with the presentation of a hyperacute type aortic dissection.

Ran Lee, MD:

In terms of medical management, the priority is impulse control, which is a combination of both heart rate and blood pressure control to slow the propagation of dissection. Specifically, we're seeking to reduce the ratio pressure change within the left ventricle, what's called the DP over DT. It decreases the LV contractility and ensures stress on the aortic wall to slow the propagation of dissection. So the main stay of treatment is IV beta blockers targeting a heart rate less than 60 beats per minute, followed by IV vasodilator therapy for a systolic blood pressure between a hundred and 120 millimeters of mercury. And as mentioned in previous presentations, analgesia for pain control. These recommendations were recently endorsed in the AATS 2021 expert consensus document on initial medical therapy.

Ran Lee, MD:

So in walking a patient through the process from arrival to a spoke center where a diagnosis is made, and the auto launch begins followed by transfer IT images to the cloud-based activation of an acute aortic syndrome network. The patient again gets transferred to the CICU where stakeholders are notified, immediate stabilization and diagnostics occur as mentioned, and the patient gets transferred to definitive therapy. So in conclusion, the CICU is the initial cardio aortic triage unit for these acute cardiac surgery emergencies, where the following diagnostics medical optimization and activation of the team can occur. Thank you.

Announcer:

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