Faculty Bibliography

Purpose: Intra-aortic balloon pumps (IABPs) can be used to provide hemodynamic support in patients with end-stage heart failure. IABPs are commonly inserted via the femoral artery, which can limit patients' mobility. The Ramsey Protocol, developed by a critical care Physical Therapist (PT), allows patients with femoral IABPs to safely transfer out of bed to a standing position using a tilt table. Our institution adapted this protocol to create a clinical practice guideline for ambulating patients with femoral IABPs.
Method(s): Our team's guideline included key components of the Ramsey Protocol, such as assessment of the patient's pre-morbid function, strength, and medical stability, as well as monitoring of IABP augmentation, IABP waveforms pre- and post-mobilization, and tilt table follow during ambulation. Appropriate candidates were patients with stable hemodynamics who were ambulatory prior to IABP placement, demonstrated against gravity muscle strength, and followed multi-step instructions.
Result(s): From April 1, 2019 to August 31, 2019, 9 patients (mean age 57 +/- 15 years) underwent IABP insertion via either right or left femoral artery, as a bridge to transplant, and were mobilized following our protocol for a total of 27 ambulation sessions (Table). There were no adverse events associated with ambulation, defined as changes in IABP augmentation, waveform, and positioning, or bleeding requiring transfusion. The mean time from IABP to ambulation was 2 +/- 2 days. All patients were successfully transplanted with mean time of IABP support of 6 +/- 3 days and all were alive at 30 days post-transplant. There were no complications during IABP support (i.e. limb ischemia, hemorrhage, stroke, device dislodgement or failure, end-organ dysfunction, or balloon rupture).
Conclusion(s): Early mobilization in select patients with femoral IABPs can be performed safely and successfully, avoiding the deleterious effects of bedrest that have been historically seen in this patient population.
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BACKGROUND:Despite innovations in left ventricular assist devices (LVAD) technology, stroke remains a leading cause of morbidity and mortality in this population. Major clinical trials of LVAD have used various definitions and approaches to measuring stroke outcomes which may limit comparison of stroke risk between different devices. METHODS:Data from the five major LVAD randomized, controlled, trials was abstracted to compare definitions of stroke (composite, ischemic, hemorrhagic and disabling) and stroke event rates across trials. Methodological limitations and suggestions to improve research and clinical practices for stroke and LVAD were identified. RESULTS:Comparison of stroke events across LVAD clinical trials is confounded by methodological variability including heterogeneity in stroke definitions, non-standardized evaluation of stroke etiology, oversimplification of stroke severity classification, and inconsistent event rate reporting due to data censoring at the time of death or transplant. Variability in the study of stroke in LVAD patients limits the ability to compare devices and design prevention strategies to mitigate stroke risk. CONCLUSIONS:Based on this review, we propose that future clinical trials: 1) utilize standardized stroke definitions and define stroke subtypes, 2) ensure that neurologists are integrated in study design and event adjudication, 3) include more thorough evaluations of stroke etiology using multimodality techniques, and 4) adopt the National Institutes of Health Stroke Scale to define stroke severity.

Background Arrhythmogenic cardiomyopathy (ACM) can mimic inflammatory processes. We present a complex patient with scleroderma (Sc)-dermatomyositis overlap syndrome (Sc-DM) and cardiac disease. Case A 57-year-old woman with family history of Sc presented with progressive weakness, dyspnea, edema, and Raynaud's (1A). Troponin was 1.6 ng/mL and CRP was 13.2 mg/L. EKGs revealed sinus rhythm with RBBB and AV sequential pacing with multifocal PVCs (1B-C). CT chest showed bibasilar fibrosis (1D). Echocardiography revealed biventricular dysfunction. Cardiac catheterization showed non-obstructive coronaries and a cardiac index of 1.8 L/min/m2. Cardiac MRI had diffuse biventricular subendocardial late gadolinium enhancement (1E). Electromyography revealed proximal myopathy. Rheumatologic workup was consistent with seronegative Sc-DM. Decision-making She was treated with steroids, mycophenolate, IV immunoglobulins, diuretics, and inotropes. Her course was complicated by recurrent VT cardiac arrests, prompting escalation to VA-ECMO. She underwent cardiac transplant on day 9 of ECMO. Pathology revealed biventricular fibrofatty replacement consistent with ACM (1F-G), patchy fibrosis of the pericardium, and mitral valve with thickened and fused chordae suggestive of inflammatory changes from Sc (1H-I). Conclusion This case highlights an atypical presentation of ACM in a patient with Sc-DM and the multidisciplinary approach necessary for proper diagnosis and management. [Figure presented]
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Controlled heart donation after circulatory determination of death (cDCD) is well-established internationally with good outcomes and could be adopted in the United States to increase heart supply if ethical and logistical challenges are comprehensively addressed. The most effective and resource-efficient method for mitigating warm ischemia after circulatory arrest is normothermic regional perfusion (NRP) in situ. This strategy requires restarting circulation after declaration of death according to circulatory criteria, which appears to challenge the legal circulatory death definition requiring irreversible cessation. Permanent cessation for life-saving efforts must be achieved to assuage this concern and ligating principal vessels maintains no blood flow to the brain, which ensures natural progression to cessation of brain function. This practice - standard in some countries - raises unique concerns about prioritizing life-saving efforts, informed authorization from decision-makers, and the clinician's role in the patient's death. To preserve public trust, medical integrity, and respect for the donor, the donation conversation must not take place until after an un-coerced decision to withdraw life-sustaining treatment made in accordance with the patient's treatment goals. The decision maker(s) must understand cDCD procedure well enough to provide genuine authorization and the preservation/procurement teams must be kept separate from the clinical care team.

Mechanical blood-immersed bearings have been used in many continuous-flow rotary blood pumps to reduce friction between relatively moving parts, but their use has been associated with a significant incidence of pump thrombosis. As newer cardiac assist devices with more advanced bearings become available, the rate of pump thrombosis will likely decrease. Nevertheless, it is important to understand the design limitations of mechanical bearings as pumps utilizing them are still in use as chronic support devices and especially in the acute setting for temporary support devices. A properly designed journal bearing should support the spinning rotor with no surface-to-surface contact between the bearing and journal surfaces. The journal continuously undergoes orbital motion within the bearing, which can be "stable" or "unstable." Unstable orbital motion causes the journal to move progressively off-center until it collides with the bearing, and even minor variations in manufacturing can create off-design operation and dynamic instability of the journal. Since blood is the lubricant in most clinically-used rotary blood pumps, lubricant viscosity can vary abruptly in response to changes in hematocrit or plasma protein concentration. Additionally, shear stress from the high-speed rotor can cause hemolysis and plasma protein denaturation. We reviewed theoretical design and operating principles of mechanical bearings and discuss why the phenomenon of mechanical bearing thrombosis may be an inherent design issue dependent on variables that are beyond the control of clinicians.

Introduction: Our institution's Adult ECMO Program started in 2015 and continues to see exponential growth with an average of 89% annual increase in volume. When demand for ECMO exceeds available resources, the multiple teams, resources and processes involved in the care of these patients are challenged to provide excellent outcomes. Our program made specific changes to accommodate increased volume while maintaining quality. Our growth directly impacted staff exposure and expertise, locations of ECMO care, emergent bedside cannulations, and utilization of equipment and supplies.
Result(s): Our team coordinated comprehensive training courses to increase the number of ECMO-credentialed physicians and advanced practice providers. We then focused on improving bedside cannulations. We provided cannulation didactic and simulation training for a cohort of critical care nurses, created a single ECMO Perfusion activation number, and increased available primed circuits. We also rebuilt our cannulation carts, using an exchange process for immediate replenishment of supplies. All carts were streamlined to one lay out and were expanded across the hospital in five different locations. We increased our equipment inventory from 9 to 15 consoles and introduced a more cost-effective ECMO system. Last, we implemented ECMO safety rounds, a biweekly bedside audit of existing safety measures that also allowed for real-time staff education.
Conclusion(s): Our patient outcomes continue to meet the national ELSO benchmarks for survival rates. As our growth continues, all areas require ongoing assessment and evaluation to maintain best practices. With proper planning and resources, quality patient outcomes can be maintained

OBJECTIVES/OBJECTIVE:Patients with low left ventricular ejection fraction (LVEF) undergoing high-risk coronary artery bypass grafting (CABG) are at increased risk for postcardiotomy cardiogenic shock. This report describes planned concomitant microaxial temporary mechanical support (MA-TMS) device placement as a viable bridge-to-recovery strategy for high-risk patients receiving surgical revascularization. METHODS:A retrospective review was performed for all patients from October 2017 to May 2019 with low LVEF (<30%), New York Heart Association Class III or IV symptoms, and myocardial viability who underwent CABG with prophylactic MA-TMS support at a single institution (n = 13). RESULTS:Mean patient age was 64.8 years, and 12 patients (92%) were male. Eight patients (62%) presented with acute coronary syndrome. Mean predicted risk of mortality was 4.6%, ranging from 0.6% to 15.6%. An average of 3.4 grafts were performed per patient. Greater than 60% of patients were extubated within 48 hours and out-of-bed within 72 hours, and the average duration of MA-TMS was 5.7 days. Mean postoperative length of stay was 16.7 days. There were no postoperative myocardial infarctions or deaths. CONCLUSIONS:Prophylactic MA-TMS may allow safe and effective surgical revascularization for patients with severe left ventricular dysfunction who may otherwise be offered a durable ventricular assist device.

Purpose: In October 2018, a new US adult heart allocation scheme was enacted in which the etiology of cardiomyopathy can play a significant role in the prioritization of patients listed for transplantation. Given this, we embarked on a review of the diagnoses of patients who underwent therapy for advanced heart failure at our center.
Method(s): We retrospectively reviewed the etiology of cardiomyopathy of patients receiving either durable ventricular assist device (VAD) or orthotopic heart transplantation (OHT) at NYU Langone Medical Center in New York, NY between January 2011 and October 2018. We evaluated for discrepancies between the primary HF diagnosis at time of operation with the ultimate diagnosis, combining both clinical follow-up data and cardiac pathology.
Result(s): During the study period, a total of 110 patients were treated with advanced therapies, of which the majority (74.5%) were male. 40.9% were African American, 35.4% Caucasian, 4.5% Asian, and 23.6% Hispanic. 86.3% underwent VAD and 22.0% underwent OHT. The average age of those undergoing OHT and VAD were 58 and 61 respectively. The most common reported etiology of HF was dilated cardiomyopathy (57.3%), followed by ischemic (36.3%), familial DCM (1.8%), amyloidosis (1.8%), restrictive cardiomyopathy (1.8%), and sarcoidosis (0.9%). On final review of the diagnoses in these patients, 14 (12.7%) had a final diagnosis that was inconsistent with the prior reported one. 5 were clerical errors, but 9 were significant deviations from the prior diagnosis. The most common diagnoses that were misidentified prior to VAD or OHT were cardiac sarcoidosis (2), cardiac amyloidosis (2), and hypertrophic cardiomyopathy (2). Among those 9 patients, 7 patients received VAD with 5 eventually requiring OHT (median days to OHT = 248); 2 patients directly received OHT. All of those are alive except one patient who was lost to follow-up (transferred care to another center). Patients in whom the diagnosis was misidentified prior to VAD or OHT had smaller LV dimensions on transthoracic echocardiography on average than other LVAD or OHT patients with non-ischemic cardiomyopathy.
Conclusion(s): In this single-center review, we found that the majority of HF patients undergoing VAD and OHT had a correct diagnosis for their heart failure prior to treatment, although notably 8.1% had a missed diagnosis at time of intervention (VAD or OHT). Appropriately identifying the subtype of cardiomyopathy remains challenging especially in advanced HF patients but can significantly impact waiting list time in the current organ allocation scheme. A normal or minimally increased LV dimension on echocardiogram in a patient with advanced non-ischemic cardiomyopathy may warrant further workup for another diagnosis.
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