Early Serial Assessment of Aggregate Vasoactive Support and Mortality in Cardiogenic Shock: Insights From the Critical Care Cardiology Trials Network Registry.

BACKGROUND: Associations of early changes in vasoactive support with cardiogenic shock (CS) mortality remain incompletely defined. METHODS: The Critical Care Cardiology Trials Network is a multicenter registry of cardiac intensive care units. Patients admitted with CS (2018-2023) had vasoactive dosing assessed at 4 and 24 hours from cardiac intensive care unit admission and quantified by the vasoactive-inotropic score (VIS). Prognostic associations of VIS at both time points, as well as change in VIS from 4 to 24 hours, were examined. Interaction testing was performed based on mechanical circulatory support status. RESULTS: Among 3665 patients, 82% had a change in VIS <10, with 7% and 11% having a ≥10-point increase and decrease from 4 to 24 hours, respectively. The 4 and 24-hour VIS were each associated with cardiac intensive care unit mortality (13%-45% and 11%-73% for VIS <10 to ≥40, respectively; Ptrend <0.0001 for each). Stratifying by the 4-hour VIS, changes in VIS from 4 to 24 hours had a graded association with mortality, ranging from a 2- to >4-fold difference in mortality comparing those with a ≥10-point increase to ≥10-point decrease in VIS (Ptrend <0.0001). The change in VIS alone provided good discrimination of cardiac intensive care unit mortality (C-statistic, 0.72 [95% CI, 0.70-0.75]) and improved discrimination of the 24-hour Sequential Organ Failure Assessment score (0.72 [95% CI, 0.69-0.74] to 0.76 [95% CI, 0.74-0.78]) and the clinician-assessed Society for Cardiovascular Angiography and Interventions shock stage (0.72 [95% CI, 0.70-0.74] to 0.77 [95% CI, 0.75-0.79]). Although present in both groups, the mortality risk associated with VIS was attenuated in patients managed with versus without mechanical circulatory support (odds ratio per 10-point higher 24-hour VIS, 1.36 [95% CI, 1.23-1.49] versus 1.84 [95% CI, 1.69-2.01]; Pinteraction <0.0001). CONCLUSIONS: Early changes in the magnitude of vasoactive support in CS are associated with a gradient of risk for mortality. These data suggest that early VIS trajectory may improve CS prognostication, with the potential to be leveraged for clinical decision-making and research applications in CS.

Variation in risk-adjusted cardiac intensive care unit (CICU) length of stay and the association with in-hospital mortality: An analysis from the Critical Care Cardiology Trials Network (CCCTN) registry.

BACKGROUND: Previous studies have suggested that there is wide variability in cardiac intensive care unit (CICU) length of stay (LOS); however, these studies are limited by the absence of detailed risk assessment at the time of admission. Thus, we evaluated inter-hospital differences in CICU LOS, and the association between LOS and in-hospital mortality. METHODS: Using data from the Critical Care Cardiology Trials Network (CCCTN) registry, we included 22,862 admissions between 2017 and 2022 from 35 primarily tertiary and quaternary CICUs that captured consecutive admissions in annual 2-month snapshots. The primary analysis compared inter-hospital differences in CICU LOS, as well as the association between CICU LOS and all-cause in-hospital mortality using a Fine and Gray competing risk model. RESULTS: The overall median CICU LOS was 2.2 (1.1-4.8) days, and the median hospital LOS was 5.9 (2.8-12.3) days. Admissions in the longest tertile of LOS tended to be younger with higher rates of pre-existing comorbidities, and had higher Sequential Organ Failure Assessment (SOFA) scores, as well as higher rates of mechanical ventilation, intravenous vasopressor use, mechanical circulatory support, and renal replacement therapy. Unadjusted all-cause in-hospital mortality was 9.3%, 6.7%, and 13.4% in the lowest, intermediate, and highest CICU LOS tertiles. In a competing risk analysis, individual patient CICU LOS was correlated (r2 = 0.31) with a higher risk of 30-day in-hospital mortality. The relationship remained significant in admissions with heart failure, ST-elevation myocardial infarction and non-ST segment elevation myocardial infarction. CONCLUSIONS: In a large registry of academic CICUs, we observed significant variation in CICU LOS and report that LOS is independently associated with all-cause in-hospital mortality. These findings could potentially be used to improve CICU resource utilization planning and refine risk prognostication in critically ill cardiovascular patients.

Defining levels of care in cardiogenic shock.

Background: Expert opinion and professional society statements have called for multi-tier care systems for the management of cardiogenic shock (CS). However, little is known about how to pragmatically define centers with different levels of care (LOC) for CS. Methods: Eleven of 23 hospitals within our healthcare system sharing a common electronic health record were classified as different LOC according to their highest mechanical circulatory support (MCS) capabilities: Level 1 (L-1)-durable left ventricular assist device, Level 1A (L-1A)-extracorporeal membrane oxygenation, Level 2 (L-2)-intra-aortic balloon pump and percutaneous ventricular assist device; and Level 3 (L-3)-no MCS. All adult patients treated for CS (International Classification of Diseases, ICD-10 code R57.0) between 2016 and 2022 were included. Etiologies of CS were identified using associated diagnostic codes. Management strategies and outcomes across LOC were compared. Results: Higher LOC centers had higher volumes: L-1 (n = 1): 2,831 patients, L-1A (n = 4): 3,452, L-2 (n = 1): 340, and L-3 (n = 5): 780. Emergency room admissions were more common in lower LOC (96% at L-3 vs. 46% L-1; p < 0.001), while hospital transfers were predominant at higher LOC (40% at L-1 vs. 2.7% at L-3; p < 0.001). Men comprised 61% of the cohort. Patients were younger in the higher LOC [69 (60-78) years at L-1 vs. 77 (67-85) years at L-3; p < 0.001]. Patients with acute myocardial infarction (AMI)-CS and acute heart failure (AHF)-CS were concentrated in higher LOC centers while other etiologies of CS were more common in L-2 and L-3 (p < 0.001). Cardiac arrest on admission was more prevalent in lower LOC centers (L-1: 2.8% vs. L-3: 12.1%; p < 0.001). Patients with AMI-CS received more percutaneous coronary intervention in lower LOC (51% L-2 vs. 29% L-1; p < 0.01) but more coronary arterial bypass graft surgery at higher LOC (L-1: 42% vs. L-1A: 23%; p < 0.001). MCS use was consistent across levels for AMI-CS but was more frequent in higher LOC for AHF-CS patients (L-1: 28% vs. L-2: 10%; p < 0.001). Despite increasing in-hospital mortality with decreasing LOC, no significant difference was seen after multivariable adjustment. Conclusion: This is the first report describing a pragmatic classification of LOC for CS which, based on MCS capabilities, can discriminate between centers with distinct demographics, practice patterns, and outcomes. This classification may serve as the basis for future research and the creation of CS systems of care.

Critical Care Cardiology Trials Network (CCCTN): a cohort profile.

AIMS: The aims of the Critical Care Cardiology Trials Network (CCCTN) are to develop a registry to investigate the epidemiology of cardiac critical illness and to establish a multicentre research network to conduct randomised clinical trials (RCTs) in patients with cardiac critical illness. METHODS AND RESULTS: The CCCTN was founded in 2017 with 16 centres and has grown to a research network of over 40 academic and clinical centres in the United States and Canada. Each centre enters data for consecutive cardiac intensive care unit (CICU) admissions for at least 2 months of each calendar year. More than 20 000 unique CICU admissions are now included in the CCCTN Registry. To date, scientific observations from the CCCTN Registry include description of variations in care, the epidemiology and outcomes of all CICU patients, as well as subsets of patients with specific disease states, such as shock, heart failure, renal dysfunction, and respiratory failure. The CCCTN has also characterised utilization patterns, including use of mechanical circulatory support in response to changes in the heart transplantation allocation system, and the use and impact of multidisciplinary shock teams. Over years of multicentre collaboration, the CCCTN has established a robust research network to facilitate multicentre registry-based randomised trials in patients with cardiac critical illness. CONCLUSION: The CCCTN is a large, prospective registry dedicated to describing processes-of-care and expanding clinical knowledge in cardiac critical illness. The CCCTN will serve as an investigational platform from which to conduct randomised controlled trials in this important patient population.

The development of endotension is associated with increased transmission of pressure and serous components in porous expanded polytetrafluoroethylene stent-grafts: characterization using a canine model.

OBJECTIVE: This study used a canine model of abdominal aortic aneurysms (AAAs) to compare intra-aneurysmal pressure and thrombus formation after exclusion with Dacron and expanded polytetrafluoroethylene (ePTFE) stent-grafts. METHODS: Prosthetic AAAs with implanted strain-gauge pressure transducers were treated by stent-graft exclusion using Food and Drug Administration-approved devices in 10 mongrel dogs: five Dacron (AneuRx) and five ePTFE (original Excluder). Intra-aneurysmal pressure was measured over 4 weeks after AAA exclusion and indexed to the systemic pressure, represented as a percentage of a simultaneously obtained systemic pressure (value = 1.0). Magnetic resonance imaging (MRI) of the intra-aneurysmal thrombus was performed at 1, 2, and 4 weeks after exclusion and expressed as a signal-to-noise ratio (S:N) to control for background signal intensity. Comparisons of pressures and S:N between the two stent-grafts was analyzed with the Student's t test. Intra-aneurysmal thrombus was characterized histologically. RESULTS: In animals excluded with both Dacron and ePTFE stent-grafts, the intra-aneurysmal pressure was nonpulsatile and reduced to <30% of systemic pressure. Significantly greater pressure transmission was observed after AAA exclusion using ePTFE compared with Dacron stent grafts (systolic pressure: ePTFE, 0.28 +/- 0.12 vs Dacron, 0.11 +/- 0.02, P < .001; mean pressure: ePTFE, 0.16 +/- 0.08 vs Dacron, 0.06 +/- 0.02, P < .001). MRI confirmed the absence of perfusion in all aneurysms. The T1-weighted signal intensity remained persistently elevated (S:N at 1 week, 2.7 +/- 0.4 vs 2 weeks, 4.0 +/- 0.2 vs 4 weeks, 5.4 +/- 1.3) in ePTFE-treated intra-aneurysmal thrombus, suggesting an absence of thrombus organization. In contrast, progressive evolution of T1 signal intensity in aneurysms excluded by Dacron stent-grafts was consistent with maturation from intact red blood cells (S:N at 1 week, 3.3 +/- 0.4) to methemoglobin (S:N at 2 weeks, 6.1 +/- 0.8), and then hemosiderin and ferritin (S:N at 4 weeks, 2.4 +/- 0.5). Histologically, ePTFE-excluded aneurysms contained poorly organized thrombus with red blood cell fragments and haphazardly arranged fibrin deposition indicative of active remodeling and continued influx of transudated serum. In aneurysms excluded by Dacron stent-grafts, dense, mature collagenous connective tissue and organized fibrin were present, indicative of greater thrombus organization. CONCLUSIONS: Stent-graft treatment reduces intra-aneurysmal pressure to <30% of systemic pressure when no endoleak is present; however, significantly greater pressure is present in aneurysms treated with porous ePTFE stent-grafts than Dacron grafts. Histologic and MRI imaging analysis suggest that active transudation of serous blood components may be contributing to this increased intra-aneurysmal pressure.