Pulmonary Artery Diastolic Pressure as a Surrogate for Pulmonary Capillary Wedge Pressure in Cardiogenic Shock.

BACKGROUND: It is common for clinicians to use the pulmonary artery diastolic pressure (PADP) as a surrogate for the pulmonary capillary wedge pressure (PCWP). Here, we determine the validity of this relationship in patients with various phenotypes of cardiogenic shock (CS). METHODS AND RESULTS: In this analysis of the Critical Care Cardiology Trials Network registry, we identified 1225 people admitted with CS who received pulmonary artery catheters. Linear regression, Bland-Altman and receiver operator characteristic analyses were performed to determine the strength of the association between PADP and PCWP in patients with left-, right-, biventricular, and other non-myocardia phenotypes of CS (eg, arrhythmia, valvular stenosis, tamponade). There was a moderately strong correlation between PADP and PCWP in the total population (r = 0.64, n = 1225) and in each CS phenotype, except for right ventricular CS, for which the correlation was weak (r = 0.43, n = 71). Additionally, we found that a PADP ≥ 24 mmHg can be used to infer a PCWP ≥ 18 mmHg with ≥ 90% confidence in all but the right ventricular CS phenotype. CONCLUSIONS: This analysis validates the practice of using PADP as a surrogate for PCWP in most patients with CS; however, it should generally be avoided in cases of right ventricular-predominant CS.

Interhospital Variation in Admissions Managed With Critical Care Therapies or Invasive Hemodynamic Monitoring in Tertiary Cardiac Intensive Care Units: An Analysis From the Critical Care Cardiology Trials Network Registry.

BACKGROUND: Wide interhospital variations exist in cardiovascular intensive care unit (CICU) admission practices and the use of critical care restricted therapies (CCRx), but little is known about the differences in patient acuity, CCRx utilization, and the associated outcomes within tertiary centers. METHODS: The Critical Care Cardiology Trials Network is a multicenter registry of tertiary and academic CICUs in the United States and Canada that captured consecutive admissions in 2-month periods between 2017 and 2022. This analysis included 17 843 admissions across 34 sites and compared interhospital tertiles of CCRx (eg, mechanical ventilation, mechanical circulatory support, continuous renal replacement therapy) utilization and its adjusted association with in-hospital survival using logistic regression. The Pratt index was used to quantify patient-related and institutional factors associated with CCRx variability. RESULTS: The median age of the study population was 66 (56-77) years and 37% were female. CCRx was provided to 62.2% (interhospital range of 21.3%-87.1%) of CICU patients. Admissions to CICUs with the highest tertile of CCRx utilization had a greater burden of comorbidities, had more diagnoses of ST-elevation myocardial infarction, cardiac arrest, or cardiogenic shock, and had higher Sequential Organ Failure Assessment scores. The unadjusted in-hospital mortality (median, 12.7%) was 9.6%, 11.1%, and 18.7% in low, intermediate, and high CCRx tertiles, respectively. No clinically meaningful differences in adjusted mortality were observed across tertiles when admissions were stratified by the provision of CCRx. Baseline patient-level variables and institutional differences accounted for 80% and 5.3% of the observed CCRx variability, respectively. CONCLUSIONS: In a large registry of tertiary and academic CICUs, there was a >4-fold interhospital variation in the provision of CCRx that was primarily driven by differences in patient acuity compared with institutional differences. No differences were observed in adjusted mortality between low, intermediate, and high CCRx utilization sites.

Shock Teams: A Contemporary Review.

PURPOSE OF REVIEW: Cardiogenic shock (CS) is a time-sensitive and often fatal condition. To address this issue, many centers have developed multidisciplinary shock teams with a common goal of expediting the recognition and treatment of CS. In this review, we examine the mission, structure, implementation, and outcomes reported by these early shock teams. RECENT FINDINGS: To date, there have been four observational shock team analyses, each providing unique insight into the utility of the shock team. The limited available data supports that shock teams are associated with improved CS mortality. However, there is considerable operational heterogeneity among shock teams, and randomized data assessing their value and best practices in both local and regional care models are needed.

Dual mechanical valve thrombosis resolution through thrombolytics: a case series.

Background: Prosthetic valve thrombosis (PVT) is a severe complication of mechanical valve replacement. Simultaneous thrombosis of multiple prosthetic valves is rare and is associated with worse outcomes. Treatment options include anticoagulation, thrombolysis, and redo operative valve replacement, with rare reports of adjunctive balloon valvuloplasty. There is limited evidence to guide therapeutic selection, specifically dosing, timing, and duration of thrombolysis. The following case series highlights the importance of successful thrombolytic management in dual PVT with high bleeding risk defined as a coagulopathy with an elevated international normalized ratio greater than 3 and New York Heart Association (NYHA) Class III and IV heart failure. Case summary: We describe two patients with concomitant aortic and mitral PVT. Both patients presented in NYHA Class III and IV heart failure with different challenges to surgical treatments including high bleeding risk from coagulopathy and history of multiple prior sternotomies. After multi-disciplinary discussions, both patients underwent a combination of low-dose, slow, or ultra-slow infusion of tissue plasminogen activator, with a resolution of their dual PVT seen on cine-fluoroscopy imaging as freely moving mechanical leaflets and improvement of heart failure symptoms back to baseline NYHA Class II or lower. Discussion: Prosthetic valve thrombosis is a complex medical condition requiring a multi-disciplinary team to evaluate the best course of treatment. A trial of pharmacologic thrombolysis is often the first attempted treatment for obstructive PVT, although surgery is recommended for patients with NYHA IV symptoms, or with contraindications to thrombolysis, including high bleeding risk. However, in patients with high bleeding risk and NYHA Class III and IV heart failure, especially with surgical contraindications, low-dose thrombolytics, with slow or ultra-slow infusions, may still be safe and effective treatment strategies for multi-valve PVT. Further research is needed to guide thrombolysis in multi-valve PVT.

Prognostic significance of haemodynamic parameters in patients with cardiogenic shock.

AIMS: Invasive haemodynamic assessment with a pulmonary artery catheter is often used to guide the management of patients with cardiogenic shock (CS) and may provide important prognostic information. We aimed to assess prognostic associations and relationships to end-organ dysfunction of presenting haemodynamic parameters in CS. METHODS AND RESULTS: The Critical Care Cardiology Trials Network is an investigator-initiated multicenter registry of cardiac intensive care units (CICUs) in North America coordinated by the TIMI Study Group. Patients with CS (2018-2022) who underwent invasive haemodynamic assessment within 24 h of CICU admission were included. Associations of haemodynamic parameters with in-hospital mortality were assessed using logistic regression, and associations with presenting serum lactate were assessed using least squares means regression. Sensitivity analyses were performed excluding patients on temporary mechanical circulatory support and adjusted for vasoactive-inotropic score. Among the 3603 admissions with CS, 1473 had haemodynamic data collected within 24 h of CICU admission. The median cardiac index was 1.9 (25th-75th percentile, 1.6-2.4) L/min/m2 and mean arterial pressure (MAP) was 74 (66-86) mmHg. Parameters associated with mortality included low MAP, low systolic blood pressure, low systemic vascular resistance, elevated right atrial pressure (RAP), elevated RAP/pulmonary capillary wedge pressure ratio, and low pulmonary artery pulsatility index. These associations were generally consistent when controlling for the intensity of background pharmacologic and mechanical haemodynamic support. These parameters were also associated with higher presenting serum lactate. CONCLUSION: In a contemporary CS population, presenting haemodynamic parameters reflecting decreased systemic arterial tone and right ventricular dysfunction are associated with adverse outcomes and systemic hypoperfusion.

Pulmonary Artery Catheter Use and Mortality in the Cardiac Intensive Care Unit.

BACKGROUND: The appropriate use of pulmonary artery catheters (PACs) in critically ill cardiac patients remains debated. OBJECTIVES: The authors aimed to characterize the current use of PACs in cardiac intensive care units (CICUs) with attention to patient-level and institutional factors influencing their application and explore the association with in-hospital mortality. METHODS: The Critical Care Cardiology Trials Network is a multicenter network of CICUs in North America. Between 2017 and 2021, participating centers contributed annual 2-month snapshots of consecutive CICU admissions. Admission diagnoses, clinical and demographic data, use of PACs, and in-hospital mortality were captured. RESULTS: Among 13,618 admissions at 34 sites, 3,827 were diagnosed with shock, with 2,583 of cardiogenic etiology. The use of mechanical circulatory support and heart failure were the patient-level factors most strongly associated with a greater likelihood of the use of a PAC (OR: 5.99 [95% CI: 5.15-6.98]; P < 0.001 and OR: 3.33 [95% CI: 2.91-3.81]; P < 0.001, respectively). The proportion of shock admissions with a PAC varied significantly by study center ranging from 8% to 73%. In analyses adjusted for factors associated with their placement, PAC use was associated with lower mortality in all shock patients admitted to a CICU (OR: 0.79 [95% CI: 0.66-0.96]; P = 0.017). CONCLUSIONS: There is wide variation in the use of PACs that is not fully explained by patient level-factors and appears driven in part by institutional tendency. PAC use was associated with higher survival in cardiac patients with shock presenting to CICUs. Randomized trials are needed to guide the appropriate use of PACs in cardiac critical care.

Management of Mechanical Prosthetic Heart Valve Thrombosis: JACC Review Topic of the Week.

Mechanical prosthetic heart valves, though more durable than bioprostheses, are more thrombogenic and require lifelong anticoagulation. Mechanical valve dysfunction can be caused by 4 main phenomena: 1) thrombosis; 2) fibrotic pannus ingrowth; 3) degeneration; and 4) endocarditis. Mechanical valve thrombosis (MVT) is a known complication with clinical presentation ranging from incidental imaging finding to cardiogenic shock. Thus, a high index of suspicion and expedited evaluation are essential. Multimodality imaging, including echocardiography, cine-fluoroscopy, and computed tomography, is commonly used to diagnose MVT and follow treatment response. Although surgery is oftentimes required for obstructive MVT, other guideline-recommended therapies include parenteral anticoagulation and thrombolysis. Transcatheter manipulation of stuck mechanical valve leaflet is another treatment option for those with contraindications to thrombolytic therapy or prohibitive surgical risk or as a bridge to surgery. The optimal strategy depends on degree of valve obstruction and the patient's comorbidities and hemodynamic status on presentation.

Clinician and Algorithmic Application of the 2019 and 2022 Society of Cardiovascular Angiography and Intervention Shock Stages in the Critical Care Cardiology Trials Network Registry.

BACKGROUND: Algorithmic application of the 2019 Society of Cardiovascular Angiography and Intervention (SCAI) shock stages effectively stratifies mortality risk for patients with cardiogenic shock. However, clinician assessment of SCAI staging may differ. Moreover, the implications of the 2022 SCAI criteria update remain incompletely defined. METHODS: The Critical Care Cardiology Trials Network is a multicenter registry of cardiac intensive care units (CICUs). Between 2019 and 2021, participating centers (n=32) contributed at least a 2-month snapshot of consecutive medical CICU admissions. In-hospital mortality was assessed across 3 separate staging methods: clinician assessment, Critical Care Cardiology Trials Network algorithmic application of the 2019 SCAI criteria, and a revision of the Critical Care Cardiology Trials Network application using the 2022 SCAI criteria. RESULTS: Of 9612 admissions, 1340 (13.9%) presented with cardiogenic shock with in-hospital mortality of 35.2%. Both clinician and algorithm-based staging using the 2019 SCAI criteria identified a stepwise gradient of mortality risk (stage C-E: 19.0% to 83.7% and 14.6% to 52.2%, respectively; Ptrend<0.001 for each). Clinician assignment of SCAI stages identified higher risk patients compared with algorithm-based assignment (stage D: 49.9% versus 29.3%; stage E: 83.7% versus 52.2%). Algorithmic application of the 2022 SCAI criteria, with incorporation of the vasoactive-inotropic score, more closely approximated clinician staging (mortality for stage C-E: 21.9% to 70.5%; Ptrend<0.001). CONCLUSIONS: Both clinician and algorithm-based application of the 2019 SCAI stages identify a stepwise gradient of mortality risk, although clinician-staging may better allocate higher risk patients into advanced SCAI stages. Updated algorithmic staging using the 2022 SCAI criteria and vasoactive-inotropic score further refines risk stratification.

The Role of Echocardiography in Extracorporeal Membrane Oxygenation.

PURPOSE OF REVIEW: Extracorporeal membrane oxygenation (ECMO) is increasingly used to temporarily support patients in severe circulatory and/or respiratory failure. Echocardiography is a core component of successful ECMO deployment. Herein, we review the role of echocardiography at different phases on extracorporeal support including candidate identification, cannulation, maintenance, complication vigilance, and decannulation. RECENT FINDINGS: During cannulation, ultrasound is used to confirm intended vascular access and appropriate inflow cannula positioning. While on ECMO, echocardiographic evaluation of ventricular loading conditions and hemodynamics, cannula positioning, and surveillance for intracardiac or aortic thrombi is needed for complication mitigation. Echocardiography is crucial during all phases of ECMO use. Specific echocardiographic queries depend on the ECMO type, V-V, or V-A, and the specific cannula configuration strategy employed.

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.

Ventilatory Ratio Is a Valuable Prognostic Indicator in an Observational Cohort of Patients With ARDS.

BACKGROUND: How indices specific to respiratory compromise contribute to prognostication in patients with ARDS is not well characterized in general clinical populations. The primary objective of this study was to identify variables specific to respiratory failure that might add prognostic value to indicators of systemic illness severity in an observational cohort of subjects with ARDS. METHODS: Fifty subjects with ARDS were enrolled in a single-center, prospective, observational cohort. We tested the contribution of respiratory variables (oxygenation index, ventilatory ratio [VR], and the radiographic assessment of lung edema score) to logistic regression models of 28-d mortality adjusted for indicators of systemic illness severity (the Acute Physiology and Chronic Health Evaluation [APACHE] III score or severity of shock as measured by the number of vasopressors required at baseline) using likelihood ratio testing. We also compared a model utilizing APACHE III with one including baseline number of vasopressors by comparing the area under the receiver operating curve (AUROC). RESULTS: VR significantly improved model performance by likelihood ratio testing when added to APACHE III (P = .036) or the number of vasopressors at baseline (P = .01). Number of vasopressors required at baseline had similar prognostic discrimination to the APACHE III. A model including the number of vasopressors and VR (AUROC 0.77 [95% CI 0.64-0.90]) was comparable to a model including APACHE III and VR (AUROC 0.81 [95% CI 0.68-0.93]; P for comparison = .58.). CONCLUSIONS: In this observational cohort of subjects with ARDS, the VR significantly improved discrimination for mortality when combined with indicators of severe systemic illness. The number of vasopressors required at baseline and APACHE III had similar discrimination for mortality when combined with VR. VR is easily obtained at the bedside and offers promise for clinical prognostication.

Impella Management for the Cardiac Intensivist.

The Impella mechanical circulatory support (MCS) system is a catheter-based continuous flow cardiac assist device that is widely used in the treatment of cardiogenic shock in medical and surgical cardiac intensive care units. As with all forms of MCS, device-related complications remain a major concern, the incidence of which can be mitigated by adhering to a few fundamental concepts in device management. The purpose of this review is to comprehensively describe our strategy for managing, repositioning, and weaning the Impella catheter.

Epidemiology of Acute Heart Failure in Critically Ill Patients With COVID-19: An Analysis From the Critical Care Cardiology Trials Network.

BACKGROUND: Acute heart failure (HF) is an important complication of coronavirus disease 2019 (COVID-19) and has been hypothesized to relate to inflammatory activation. METHODS: We evaluated consecutive intensive care unit (ICU) admissions for COVID-19 across 6 centers in the Critical Care Cardiology Trials Network, identifying patients with vs without acute HF. Acute HF was subclassified as de novo vs acute-on-chronic, based on the absence or presence of prior HF. Clinical features, biomarker profiles and outcomes were compared. RESULTS: Of 901 admissions to an ICU due to COVID-19, 80 (8.9%) had acute HF, including 18 (2.0%) with classic cardiogenic shock (CS) and 37 (4.1%) with vasodilatory CS. The majority (n = 45) were de novo HF presentations. Compared to patients without acute HF, those with acute HF had higher cardiac troponin and natriuretic peptide levels and similar inflammatory biomarkers; patients with de novo HF had the highest cardiac troponin levels. Notably, among patients critically ill with COVID-19, illness severity (median Sequential Organ Failure Assessment, 8 [IQR, 5-10] vs 6 [4-9]; P = 0.025) and mortality rates (43.8% vs 32.4%; P = 0.040) were modestly higher in patients with vs those without acute HF. CONCLUSIONS: Among patients critically ill with COVID-19, acute HF is distinguished more by biomarkers of myocardial injury and hemodynamic stress than by biomarkers of inflammation.

Management and Outcomes of Cardiogenic Shock in Cardiac ICUs With Versus Without Shock Teams.

BACKGROUND: Single-center studies suggest that implementation of multidisciplinary cardiogenic shock (CS) teams is associated with improved CS survival. OBJECTIVES: The aim was to characterize practice patterns and outcomes in the management of CS across multiple centers with versus without shock teams. METHODS: The Critical Care Cardiology Trials Network is a multicenter network of cardiac intensive care units (CICUs) in North America. All consecutive medical admissions to each CICU (n = 24) were captured during annual 2-month collection periods (2017-2019; n = 6,872). Shock management and CICU mortality among centers with versus without shock teams were compared using inverse probability weighting. RESULTS: Ten of the 24 centers had shock teams. Among 1,242 CS admissions, 44% were at shock team centers. The groups were well-balanced with respect to demographics, shock etiology, Sequential Organ Failure Assessment score, biochemical markers of end organ dysfunction, and invasive hemodynamics. Centers with shock teams used more pulmonary artery catheters (60% vs 49%; adjusted odds ratio [OR]: 1.86; 95% CI: 1.47-2.35; P < 0.001), less overall mechanical circulatory support (MCS) (35% vs 43%; adjusted OR: 0.74; 95% CI: 0.59-0.95; P = 0.016), and more advanced types of MCS (53% vs 43% of all MCS; adjusted OR: 1.73; 95% CI: 1.19-2.51; P = 0.005) rather than intra-aortic balloon pumps. The presence of a shock team was independently associated with lower CICU mortality (23% vs 29%; adjusted OR: 0.72; 95% CI: 0.55-0.94; P = 0.016). CONCLUSIONS: In this multicenter observational study, centers with shock teams were more likely to obtain invasive hemodynamics, use advanced types of MCS, and have lower risk-adjusted mortality. A standardized multidisciplinary shock team approach may improve outcomes in CS.

Echocardiographic assessment of pulmonary arterial capacitance predicts mortality in pulmonary hypertension.

BACKGROUND: Pulmonary arterial capacitance (PAC) is one of the strongest predictors of clinical outcomes in patients with pulmonary hypertension (PH). We examined the value of an echocardiographic surrogate for PAC (ePAC) as a predictor of mortality in patients with PH. METHODS: We performed a retrospective study of 302 patients with PH managed at a PH comprehensive care center over a cumulative follow-up time of 858 patient-years. Charts from 2004 to 2018 were reviewed to identify patients in whom a right heart catheterization (RHC) was performed within two months of an echocardiogram. Standard invasive, non-invasive, functional, and biochemical prognostic markers were extracted from the time of RHC. The primary outcome was all-cause mortality. Cox proportional hazards models were used to model the time from RHC to the primary outcome or last medical contact. RESULTS: Variables associated with all-cause mortality included ePAC [standardized hazard ratio (HR) 0.68, 95% CI 0.48-0.98, p = 0.036], RHC-PAC (HR 0.68, 95% CI 0.48-0.96, p = 0.027), echocardiographic pulmonary vascular resistance (HR 1.29, 95% CI 1.05-1.60, p = 0.017), six-minute walk distance (HR 0.43, 95% CI 0.23-0.82, p = 0.01), and B-type natriuretic peptide (HR 1.29, 95% CI 1.03-1.62, p = 0.027). In multivariable-adjusted Cox analysis, ePAC predicted all-cause mortality independently of age, gender, and multiple comorbidities. There was a graded and stepwise association between low (<0.15 cm/mmHg), medium (0.15-0.25 cm/mmHg), and high (>0.25 cm/mmHg) tertiles of ePAC and all-cause mortality. CONCLUSIONS: We have demonstrated that ePAC is a readily available echocardiographic marker that independently predicts mortality in PH, and have provided clinically relevant ranges by which to risk-stratify patients and predict mortality.

Spectrum of Cardiac Involvement in COVID-19.

Cardiac involvement in coronavirus disease 2019 (COVID-19) commonly accompanies multi-organ system failure with acute respiratory syndrome; however, infrequently myocarditis and pericardial effusions may be isolated, yet fulminant. In this report, we highlight significant variations in cardiac involvement and presentation among patients with COVID-19. This article reports two cases of fulminant myocarditis in COVID-19 positive patients who presented to our facility with contrasting symptoms, laboratory and imaging findings. A 65-year-old patient A had a more typical presentation including respiratory distress, chest pain, ST-segment elevations on electrocardiogram (EKG), lymphopenia, elevated levels of inflammatory markers and cardiac troponin I. A 34-year-old patient B presented with shortness of breath and chest pain similar to patient A; however, she had isolated cardiac involvement with systolic dysfunction and an acute pericardial effusion causing tamponade physiology. Inflammatory marker and cardiac troponin I levels for patient B were within normal range. Patient A had a rapid progression of multi-organ system failure leading to her death within 24 hours from presentation on maximal inopressor support. Patient B, however, is one of few reported cases of cardiac tamponade and veno-arterial extracorporeal membrane oxygenation (VA-ECMO) use in COVID-19 who underwent pericardiocentesis and was additionally managed with colchicine and steroids, leading to complete recovery in systolic function within three weeks from initial presentation. Isolated myocardial dysfunction and pericardial effusions in COVID-19 may have catastrophic sequalae even in the absence of elevated biomarkers described in literature. Therefore, early detection and management of cardiac involvement is warranted. Additionally, the role of mechanical circulatory support devices and VA-ECMO in COVID-19 needs further investigation.

Pulmonary arterial capacitance predicts outcomes in patients with pulmonary hypertension independent of race/ethnicity, sex, and etiology.

BACKGROUND: Pulmonary arterial capacitance (PAC) is a strong hemodynamic predictor of outcomes in patients with pulmonary hypertension (PH). Its value across subgroups of race/ethnicity, sex, and PH etiologies is unclear. We hypothesized that the association of PAC with outcomes would not vary across World Health Organization (WHO) PH group, race/ethnicity, or sex. METHODS: We performed a retrospective study in patients with PH diagnosed and managed at the Pulmonary Hypertension Comprehensive Care Center of a tertiary care hospital (n = 270). Demographic, diagnostic, treatment, and outcome data were extracted from the electronic medical record. Cox proportional hazards models were used to model time from right heart catheterization to event in univariate and multivariable models. Our primary outcome was all-cause mortality and our secondary outcome was PH hospitalization. RESULTS: The median age of the cohort was 56 years (±14.6), and 67% were female. In multivariable Cox models adjusted for significant covariates, decreased PAC remained independently and significantly associated with both all-cause mortality (p = 0.029) and hospitalization for PH (p = 0.010). No significant interactions were observed between PAC and race, sex, or WHO group. Hispanic patients exhibited a significant independent association with increased hospitalizations (p = 0.030), and there was a trend toward increased all-cause mortality in African Americans. WHO group 2 PH was associated with more frequent hospitalization (p = 0.004). CONCLUSIONS: Decreased PAC is significantly associated with mortality and hospitalization in PH patients independent of race, sex, and PH subgroups. Further investigation is required to characterize the effects and determinants of racial disparities in PH.

Clinical Practice Patterns in Temporary Mechanical Circulatory Support for Shock in the Critical Care Cardiology Trials Network (CCCTN) Registry.

BACKGROUND: Temporary mechanical circulatory support (MCS) devices provide hemodynamic assistance for shock refractory to pharmacological treatment. Most registries have focused on single devices or specific etiologies of shock, limiting data regarding overall practice patterns with temporary MCS in cardiac intensive care units. METHODS: The CCCTN (Critical Care Cardiology Trials Network) is a multicenter network of tertiary CICUs in North America. Between September 2017 and September 2018, each center (n=16) contributed a 2-month snapshot of consecutive medical CICU admissions. RESULTS: Of the 270 admissions using temporary MCS, 33% had acute myocardial infarction-related cardiogenic shock (CS), 31% had CS not related to acute myocardial infarction, 11% had mixed shock, and 22% had an indication other than shock. Among all 585 admissions with CS or mixed shock, 34% used temporary MCS during the CICU stay with substantial variation between centers (range: 17%-50%). The most common temporary MCS devices were intraaortic balloon pumps (72%), Impella (17%), and veno-arterial extracorporeal membrane oxygenation (11%), although intraaortic balloon pump use also varied between centers (range: 40%-100%). Patients managed with intraaortic balloon pump versus other forms of MCS (advanced MCS) had lower Sequential Organ Failure Assessment scores and less severe metabolic derangements. Illness severity was similar at high- versus low-MCS utilizing centers and at centers with more advanced MCS use. CONCLUSIONS: There is wide variation in the use of temporary MCS among patients with shock in tertiary CICUs. While hospital-level variation in temporary MCS device selection is not explained by differences in illness severity, patient-level variation appears to be related, at least in part, to illness severity.

Noninvasive estimation of pulmonary vascular resistance improves portopulmonary hypertension screening in liver transplant candidates.

Despite limitations in sensitivity and specificity, estimation of the pulmonary artery systolic pressure (ePASP) on echocardiography is used for portopulmonary hypertension (PoPH) screening in liver transplant (LT) candidates. We proposed that alternative echocardiographic models, such as estimated pulmonary vascular resistance (ePVR), may provide improved testing characteristics in PoPH screening. In a retrospective analysis of 100 LT candidates, we found that the formula ePVR = ePASP/VTIRVOT  + 3 if MSN (VTIRVOT  = right ventricular outflow tract time velocity integral; MSN = mid-systolic notching of the VTIRVOT Doppler signal) significantly improves accuracy of PoPH screening compared to ePASP. We determined the optimal ePVR cutoff for PoPH screening to be 2.76 Wood units, as this cutoff provided 100% sensitivity and 73% specificity in screening for clinically significant PoPH. Comparatively, ePASP at a cutoff of 40 mm Hg provided 91% sensitivity and 48% specificity. We devised a new screening algorithm based on the use of ePVR at intermediate ePASP values (35-54 mm Hg), and we confirmed the testing characteristics of this algorithm in a separate validation cohort of 50 LT candidates. In screening LT candidates for PoPH, the ePASP lacks accuracy, leading to unnecessary RHCs and undiagnosed cases of PoPH. A screening algorithm which incorporates the ePVR may be more reliable.