Modification of a Transvalvular Microaxial Flow Pump for Instantaneous Determination of Native Cardiac Output and Volume.

BACKGROUND: The current Impella cardiopulmonary (CP) pump, used for mechanical circulatory support in patients with cardiogenic shock (CS), cannot assess native cardiac output (CO) and left ventricular (LV) volumes. These data are valuable in facilitating device management and weaning. Admittance technology allows for accurate assessment of cardiac chamber volumes. OBJECTIVES: This study tested the ability to engineer admittance electrodes onto an existing Impella CP pump to assess total and native CO as well as LV chamber volumes in an instantaneous manner. METHODS: Impella CP pumps were fitted with 4 admittance electrodes and were placed in the LVs of adult swine (n = 9) that were subjected to 3 different hemodynamic conditions, including Impella CP speed adjustments, administration of escalating doses of dobutamine and microsphere injections into the left main artery to result in cardiac injury. CO, according to admittance electrodes, was calculated from LV volumes and heart rate. In addition, CO was calculated in each instance via thermodilution, continuous CO measurement, the Fick principle, and aortic velocity-time integral by means of echocardiography. RESULTS: Modified Impella CP pumps were placed in swine LVs successfully. CO, as determined by admittance electrodes, was similar by trend to other methods of CO assessment. It was corrected for pump speed to calculate native CO, and calculated LV chamber volumes trended as expected in each experimental protocol. CONCLUSIONS: We report, for the first time, that an Impella CP pump can be fitted with admittance electrodes and used to determine total and native CO in various hemodynamic situations. CONDENSED ABSTRACT: Transvalvular mechanical circulatory support devices such as the Impella CP do not have the ability to provide real-time information on native cardiac output (CO) and left ventricular (LV) volumes. This information is critical in device management and in weaning in patients with cardiogenic shock. We demonstrate, for the first time, that Impella CP pumps coupled with admittance electrodes are able to determine native CO and LV chamber volumes in multiple hemodynamic situations such as Impella pump speed adjustments, escalating dobutamine administration and cardiac injury from microsphere injection.

A Comprehensive Review of Calcineurin Inhibitors Used for Immunosuppression in Cardiac Transplantation.

Calcineurin inhibitors (CNIs) have been the foundation of immunosuppression in solid organ transplantation since the 1980s. Cyclosporine A (CSA), the first in class, was identified as the metabolite of the soil fungus Tolypocladium inflatum Gams as part of a larger program of screening for naturally occurring fungal metabolites with biologic activity in the 1970s. Significant immunosuppressive effects were discovered and consequently CSA was trialed as an immunosuppressant in renal transplantation. This initial success led to its widespread study and adoption in solid organ transplantation. This novel agent yielded significant improvements in both 1 year and longer-term allograft and patient survival. Subsequently, a similar and more potent CNI, tacrolimus was developed. Today, it is the principal CNI used for prevention of allograft rejection. Like all other immunosuppressives, the benefits of CNIs are counterbalanced by side effects and complications resulting from drug toxicity. This chapter comprehensively reviews the clinical use of CNIs in cardiac transplantation.

Between-center variation in high-priority listing status under the new heart allocation policy.

Under the new US heart allocation policy, transplant centers listed significantly more candidates at high priority statuses (Status 1 and 2) with mechanical circulatory support devices than expected. We determined whether the practice change was widespread or concentrated among certain transplant centers. Using data from the Scientific Registry of Transplant Recipients, we used mixed-effect logistic regression to compare the observed listings of adult, heart-alone transplant candidates post-policy (December 2018 to February 2020) to seasonally matched pre-policy cohort (December 2016 to February 2018). US transplant centers (N = 96) listed similar number of candidates in each policy period (4472 vs. 4498) but listed significantly more at high priority status (25.5% vs. 7.0%, p < .001) than expected. Adjusted for candidate characteristics, 91 of 96 (94.8%) centers listed significantly more candidates at high-priority status than expected, with the unexpected increase varying from 4.8% to 50.4% (interquartile range [IQR]: 14.0%-23.3%). Centers in OPOs with highest Status 1A transplant rate pre-policy were significantly more likely to utilize high-priority status under the new policy (OR: 9.73, p = .01). The new heart allocation policy was associated with widespread and significantly variable changes in transplant center practice that may undermine the effectiveness of the new system.

Cardiac transplantation outcomes in patients with amyloid cardiomyopathy.

OBJECTIVE: Amyloid cardiomyopathy (ACM) is a progressive and life-threatening disease caused by abnormal protein deposits within cardiac tissue. The most common forms of ACM are caused by immunoglobulin derived light chains (AL) and transthyretin (TTR). Orthotopic heart transplantation (OHT) remains the definitive treatment for patients with end stage heart failure. In this study, we perform a contemporary multicenter analysis evaluating post OHT survival in patients with ACM. METHODS: We conducted a multicenter analysis of 40,044 adult OHT recipients captured in the United Network for Organ Sharing (UNOS) registry from 1987-2018. Patients were characterized as ACM or non-ACM. Baseline characteristics were obtained, and summary characteristics were calculated. Outcomes of interest included post-transplant survival, infection, treated rejection, and the ability to return to work. Racial differences in OHT survival were also analyzed. Unadjusted associations between ACM and non-ACM survival were determined using the Kaplan-Meier estimations and confounding was addressed using multivariable Cox proportional hazards models. RESULTS: Three hundred ninety-eight patients with a diagnosis of ACM were identified of which 313 underwent heart only OHT. ACM patients were older (61 vs 53; P < .0001) and had a higher proportion of African Americans (30.7% vs 17.6%; P < .0001). Median survival for ACM was 10.2 years vs 12.5 years in non-ACM (P = .01). After adjusting for confounding, ACM patients had a higher likelihood of death post-OHT (HR 1.39 CI: 1.14, 1.70; P = .001). African American ACM patients had a higher likelihood of survival compared to White ACM patients (HR 0.51 CI 0.31-0.85; P = .01). No difference was observed in episodes of treated rejection (OR 0.63 CI 0.23, 1.78; P = .39), hospitalizations for infections (OR 1.24 CI: 0.85, 1.81; P = .26), or likelihood of returning to work for income (OR 1.23 CI: 0.84, 1.80; P = .30). CONCLUSIONS: In this analysis of OHT in ACM, ACM was associated with a higher likelihood of post-OHT mortality. Racial differences in post-OHT were observed with African American patients with ACM having higher likelihood of survival compared to White patients with ACM. No differences were observed in episodes of treated rejection, hospitalization for infection, or likelihood to return to work for income.

Intrapericardial Left Ventricular Assist Device for Advanced Heart Failure.

BACKGROUND: Mechanical circulatory support with a left ventricular assist device (LVAD) is an established treatment for patients with advanced heart failure. We compared a newer LVAD design (a small intrapericardial centrifugal-flow device) against existing technology (a commercially available axial-flow device) in patients with advanced heart failure who were ineligible for heart transplantation. METHODS: We conducted a multicenter randomized trial involving 446 patients who were assigned, in a 2:1 ratio, to the study (centrifugal-flow) device or the control (axial-flow) device. Adults who met contemporary criteria for LVAD implantation for permanent use were eligible to participate in the trial. The primary end point was survival at 2 years free from disabling stroke or device removal for malfunction or failure. The trial was powered to show noninferiority with a margin of 15 percentage points. RESULTS: The intention-to treat-population included 297 participants assigned to the study device and 148 participants assigned to the control device. The primary end point was achieved in 164 patients in the study group and 85 patients in the control group. The analysis of the primary end point showed noninferiority of the study device relative to the control device (estimated success rates, 55.4% and 59.1%, respectively, calculated by the Weibull model; absolute difference, 3.7 percentage points; 95% upper confidence limit, 12.56 percentage points; P=0.01 for noninferiority). More patients in the control group than in the study group had device malfunction or device failure requiring replacement (16.2% vs. 8.8%), and more patients in the study group had strokes (29.7% vs. 12.1%). Quality of life and functional capacity improved to a similar degree in the two groups. CONCLUSIONS: In this trial involving patients with advanced heart failure who were ineligible for heart transplantation, a small, intrapericardial, centrifugal-flow LVAD was found to be noninferior to an axial-flow LVAD with respect to survival free from disabling stroke or device removal for malfunction or failure. (Funded by HeartWare; ENDURANCE ClinicalTrials.gov number, NCT01166347 .).

Evaluating Biventricular Myocardial Velocity and Interventricular Dyssynchrony in Adult Patients During the First Year After Heart Transplantation.

BACKGROUND: Magnetic resonance tissue phase mapping (TPM) measures three-directional myocardial velocities of the left and right ventricle (LV, RV). This noninvasive technique may supplement endomyocardial biopsy (EMB) in monitoring grafts post-heart transplantation (HTx). PURPOSE: To assess biventricular myocardial velocity alterations in grafts and investigate the relationship between velocities and acute cellular rejection (ACR) episodes. STUDY TYPE: Prospective. SUBJECTS: Twenty-seven patients within 1 year post-HTx (49 ± 13 years, 19 M) and 18 age-matched controls (49 ± 15 years, 12 M). FIELD STRENGTH/SEQUENCE: 1.5T, 2D balanced steady-state free precession, and TPM. ASSESSMENT: Ventricular function: end-diastolic and end-systolic volumes, stroke volumes, ejection fraction (EF), and myocardial mass. TPM velocities: peak-systolic and peak-diastolic velocities, cardiac twist, and interventricular dyssynchrony. ACR rejection episodes: International Society for Heart and Lung Transplantation grading of EMB specimens. STATISTICAL TESTS: The Lilliefors test for normality, unpaired t-tests, and Wilcoxon rank-sum tests for normally and nonnormally distributed data, respectively, were used, as well as multivariate regression for confounding variables and Pearson's correlation for associations between TPM velocities and global function. RESULTS: Compared to controls, HTx patients demonstrated reduced biventricular systolic longitudinal velocities (LV: 5.2 ± 2.1 vs. 4.0 ± 1.5 cm/s, P < 0.05; RV: 4.2 ± 1.3 vs. 3.1 ± 1.2 cm/s, P < 0.01). Correlation analysis revealed significant positive relationships for biventricular EF with radial peak velocities of the same ventricle in both systole and diastole (LV systole: r = 0.48, P < 0.01; LV diastole: r = 0.28, P < 0.05; RV systole: r = 0.35, P < 0.01; RV diastole: r = 0.36, P < 0.01). Segmentally, longitudinal velocities were impaired in 7/16 LV segments and 5/10 RV segments in systole and 7/10 RV segments in diastole. TPM analysis in studies with >4 preceding ACR episodes showed globally reduced RV and LV systolic radial velocity, and segmentally reduced radial and longitudinal systolic velocities. DATA CONCLUSION: Biventricular global and segmental velocities were reduced in HTx patients. Patients with >4 rejection episodes showed reduced myocardial velocities. The TPM sequence may add functional information for monitoring graft dysfunction. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 2 J. Magn. Reson. Imaging 2020;52:920-929.

Mineralocorticoid Receptor Antagonists: a Comprehensive Review of Finerenone.

PURPOSE OF REVIEW: We aim to review the mechanism of action and safety profile of mineralocorticoid receptor antagonists (MRAs) and discuss the differences between selective and non-selective MRAs. More specifically, finerenone is a new medication that is currently under investigation for its promising cardiovascular and nephrological effects. RECENT FINDINGS: MRAs are well known for their utility in treating heart failure, refractory hypertension, and diverse nephropathies, namely, diabetic nephropathy. As their name denotes, MRAs inhibit the action of aldosterone at the mineralocorticoid receptor, preventing receptor activation. This prevents remodeling, decreases inflammation, and improves proteinuria. There are not significant differences in outcomes between selective and non-selective MRAs. A new selective MRA named finerenone (originally BAY 94-8862) has shown promising results in several trials (ARTS-HF and ARTS-DN) and smaller studies. Finerenone may have a dose-dependent benefit over older MRAs, decreasing rates of albuminuria and levels of BNP and NT-ProBNP without causing a significant increase in serum potassium levels. This medication is not yet approved as it is still in phase 3 clinical trials (FIGARO-DKD and FIDELIO-DKD trials). MRAs are beneficial in several disease states. Newer medications, such as finerenone, should be considered in patients with heart failure and diabetic nephropathy who may benefit from a reduction in albuminuria and BNP/NT-ProBNP. Data surrounding finerenone are limited to date. However, results from ongoing clinical trials, as well as new trials to evaluate use in other pathologies, could validate the implementation of this medication in daily practice.

Outcomes in Patients with COVID-19 Infection Taking ACEI/ARB.

PURPOSE OF REVIEW: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus responsible for the aggressive coronavirus disease (COVID-19) pandemic. Recently, investigators have stipulated that COVID-19 patients receiving angiotensin-converting-enzyme inhibitors (ACEI) may be subject to poorer outcomes. This editorial presents the available evidence to guide treatment practices during this pandemic. RECENT FINDINGS: Recent studies from Wuhan cohorts provide valuable information about COVID-19. A cohort with 52 critically ill patients revealed cardiac injury in 12% of patients. Worse outcomes appear to be more prevalent in patients with hypertension and diabetes mellitus (DM), possibly due to overexpression of angiotensin-converting enzyme 2 (ACE2) receptor in airway alveolar epithelial cells. Investigators suspect that SARS-CoV-2 uses the ACE2 receptor to enter the lungs in a mechanism similar to SARS-CoV. Several hypotheses have been proposed to date regarding the net effect of ACEI/ARB on COVID-19 infections. Positive effects include ACE2 receptor blockade, disabling viral entry into the heart and lungs, and an overall decrease in inflammation secondary to ACEI/ARB. Negative effects include a possible retrograde feedback mechanism, by which ACE2 receptors are upregulated. Even though physiological models of SARS-CoV infection show a theoretical benefit of ACEI/ARB, these findings cannot be extrapolated to SARS-CoV-2 causing COVID-19. Major cardiology scientific associations, including ACC, HFSA, AHA, and ESC Hypertension Council, have rejected these correlation hypotheses. After an extensive literature review, we conclude that there is no significant evidence to support an association for now, but given the rapid evolvement of this pandemic, findings may change.

The Role of Anticoagulation in COVID-19-Induced Hypercoagulability.

PURPOSE OF REVIEW: We aim to provide a comprehensive analysis of hypercoagulability in individuals affected by COVID-19. Our goal is to describe the hypercoagulable state related to the infection and provide guidance regarding the possible benefits of anti-coagulation with the support of evidence from current literature. RECENT FINDINGS: The incidence of thrombotic disease in individuals affected by COVID-19 is reported as high as 31%. A significant mortality benefit has been observed with the use of therapeutic anticoagulation in high-risk individuals. Literature supports the use of scoring systems, such as the sepsis-induced coagulopathy score, to risk-stratify individuals who might benefit from anticoagulation. COVID-19-induced hypercoagulability has been demonstrated to play a significant role in overall COVID-19 outcomes. Current literature shows promising evidence with the use of therapeutic anticoagulation in high-risk individuals. Further studies are needed to better analyze the risks and benefits of anticoagulation in this specific patient population.

Cardiac Structure-Function MRI in Patients After Heart Transplantation.

BACKGROUND: Following heart transplantation (Tx), recipients are closely monitored using endomyocardial biopsy, which is limited by cost and invasiveness, and echocardiography, which is limited regarding detailed structural and functional evaluation. PURPOSE: To test the feasibility of comprehensive structure-function cardiac MRI as a noninvasive modality to assess changes in myocardial structure and function. STUDY TYPE: Prospective. SUBJECTS: MR was performed in 61 heart transplant recipients (age 47.9 ± 16.3 years, 39% female) and 14 age-matched healthy controls (age 47.7 ± 16.7 years, 36% female). FIELD STRENGTH/SEQUENCE: 1.5T; 2D CINE steady state free precession (SSF)P imaging, T2 -mapping, pre- and postgadolinium contrast T1 -mapping, and tissue-phase mapping (TPM). ASSESSMENT: Quantification of myocardial T2 (as a measure of edema), pre- and post-Gd T1 (allowing calculation of extracellular volume (ECV) to estimate interstitial expansion), and TPM-based assessment of peak regional left ventricular (LV) velocities, dyssynchrony, and twist. STATISTICAL TESTS: Comparisons between transplant recipients and controls were performed using independent samples t-tests. Relationships between structural (T2 , T1 , ECV) and functional measures (myocardial velocities, dyssynchrony, twist) were assessed using Pearson correlation analysis. RESULTS: T2 and T1 were significantly elevated in transplant recipients compared to controls (global T2 : 50.5 ± 3.4 msec vs. 45.2 ± 2.3 msec, P < 0.01; global T1 : 1037.8 ± 48.0 msec vs. 993.8 ± 34.1 msec, P < 0.01). Systolic longitudinal function was impaired in transplant recipients compared to controls (reduced peak systolic longitudinal velocities, 2.9 ± 1.1 cm/s vs. 5.1 ± 1.2 cm/s, P < 0.01; elevated systolic longitudinal dyssynchrony, 60.2 ± 30.2 msec vs. 32.1 ± 25.1 msec, P < 0.01). Correlation analysis revealed a significant positive relationship between T2 and ECV (r = 0.45,P < 0.01). In addition, peak systolic longitudinal velocities demonstrated a significant inverse relationship with T2 (global r = -0.29, P = 0.02), and systolic radial dyssynchrony was positively associated with peak T2 and peak T1 (r = 0.26,P = 0.04; r = 0.27,P = 0.03). DATA CONCLUSION: MR techniques are sensitive to structural and functional differences in transplant recipients compared to controls. Structural (T2 , T1 ) and functional (peak myocardial velocities, dyssynchrony) measures were significantly associated, suggesting a structure-function relationship of cardiac abnormalities following heart transplant. LEVEL OF EVIDENCE: 2 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2019;49:678-687.

Intravenous Allogeneic Mesenchymal Stem Cells for Nonischemic Cardiomyopathy: Safety and Efficacy Results of a Phase II-A Randomized Trial.

RATIONALE: Potential benefits of mesenchymal stem cell (MSC) therapy in heart failure may be related to paracrine properties and systemic effects, including anti-inflammatory activities. If this hypothesis is valid, intravenous administration of MSCs should improve outcomes in heart failure, an entity in which excessive chronic inflammation may play a pivotal role. OBJECTIVE: To assess the safety and preliminary efficacy of intravenously administered ischemia-tolerant MSCs (itMSCs) in patients with nonischemic cardiomyopathy. METHODS AND RESULTS: This was a single-blind, placebo-controlled, crossover, randomized phase II-a trial of nonischemic cardiomyopathy patients with left ventricular ejection fraction ≤40% and absent hyperenhancement on cardiac magnetic resonance imaging. Patients were randomized to intravenously administered itMSCs (1.5×106 cells/kg) or placebo; at 90 days, each group received the alternative treatment. Overall, 22 patients were randomized to itMSC (n=10) and placebo (n=12) at baseline. After crossover, data were available for 22 itMSC patients. No major differences in death, hospitalization, or serious adverse events were noted between the 2 treatments. Change from baseline in left ventricular ejection fraction and ventricular volumes was not significantly different between therapies. Compared with placebo, itMSC therapy increased 6-minute walk distance (+36.47 m, 95% confidence interval 5.98-66.97; P=0.02) and improved Kansas City Cardiomyopathy clinical summary (+5.22, 95% confidence interval 0.70-9.74; P=0.02) and functional status scores (+5.65, 95% confidence interval -0.11 to 11.41; P=0.06). The data demonstrated MSC-induced immunomodulatory effects, the magnitude of which correlated with improvement in left ventricular ejection fraction. CONCLUSIONS: In this pilot study of patients with nonischemic cardiomyopathy, itMSC therapy was safe, caused immunomodulatory effects, and was associated with improvements in health status and functional capacity. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02467387.

Association of Transplant Center With Survival Benefit Among Adults Undergoing Heart Transplant in the United States.

Importance: In the United States, the number of deceased donor hearts available for transplant is limited. As a proxy for medical urgency, the US heart allocation system ranks heart transplant candidates largely according to the supportive therapy prescribed by transplant centers. Objective: To determine if there is a significant association between transplant center and survival benefit in the US heart allocation system. Design, Setting, and Participants: Observational study of 29 199 adult candidates for heart transplant listed on the national transplant registry from January 2006 through December 2015 with follow-up complete through August 2018. Exposures: Transplant center. Main Outcomes and Measures: The survival benefit associated with heart transplant as defined by the difference between survival after heart transplant and waiting list survival without transplant at 5 years. Each transplant center's mean survival benefit was estimated using a mixed-effects proportional hazards model with transplant as a time-dependent covariate, adjusted for year of transplant, donor quality, ischemic time, and candidate status. Results: Of 29 199 candidates (mean age, 52 years; 26% women) on the transplant waiting list at 113 centers, 19 815 (68%) underwent heart transplant. Among heart transplant recipients, 5389 (27%) died or underwent another transplant operation during the study period. Of the 9384 candidates who did not undergo heart transplant, 5669 (60%) died (2644 while on the waiting list and 3025 after being delisted). Estimated 5-year survival was 77% (interquartile range [IQR], 74% to 80%) among transplant recipients and 33% (IQR, 17% to 51%) among those who did not undergo heart transplant, which is a survival benefit of 44% (IQR, 27% to 59%). Survival benefit ranged from 30% to 55% across centers and 31 centers (27%) had significantly higher survival benefit than the mean and 30 centers (27%) had significantly lower survival benefit than the mean. Compared with low survival benefit centers, high survival benefit centers performed heart transplant for patients with lower estimated expected waiting list survival without transplant (29% at high survival benefit centers vs 39% at low survival benefit centers; survival difference, -10% [95% CI, -12% to -8.1%]), although the adjusted 5-year survival after transplant was not significantly different between high and low survival benefit centers (77.6% vs 77.1%, respectively; survival difference, 0.5% [95% CI, -1.3% to 2.3%]). Overall, for every 10% decrease in estimated transplant candidate waiting list survival at a given center, there was an increase of 6.2% (95% CI, 5.2% to 7.3%) in the 5-year survival benefit associated with heart transplant. Conclusions and Relevance: In this registry-based study of US heart transplant candidates, transplant center was associated with the survival benefit of transplant. Although the adjusted 5-year survival after transplant was not significantly different between high and low survival benefit centers, compared with centers with survival benefit significantly below the mean, centers with survival benefit significantly above the mean performed heart transplant for recipients who had significantly lower estimated expected 5-year waiting list survival without transplant.

A Prospective Pilot Study of Pocket-Carried Ultrasound Pre- and Postdischarge Inferior Vena Cava Assessment for Prediction of Heart Failure Rehospitalization.

BACKGROUND: Rehospitalization for heart failure (HF) is common, and subclinical congestion may be present at discharge. Larger inferior vena cava (IVC) size and lower collapsibility at discharge assessed via bedside ultrasound are predictive of rehospitalization; however, the utility of IVC assessment with the use of pocket-carried ultrasound (PCUS) during the transition from discharge to the posthospitalization follow-up visit (FU) has not been investigated. METHODS AND RESULTS: IVCmax and IVCmin were measured with the use of PCUS, and the collapsibility index (IVCCI = [IVCmax - IVCmin]/IVCmax) was determined. The primary outcome was 90-day rehospitalization or death. We prospectively enrolled 49 adults (71 ± 13 years of age, 51% male, 47% black, 43% preserved ejection fraction) hospitalized for HF. Nineteen patients (39%) experienced the outcome. Within the rehospitalized group, discharge and FU mean IVCmax were both >2.1 cm (2.2 ± 0.5 and 2.2 ± 0.7) and IVCCIs <50% (44 ± 20% and 45 ± 24%). Within those not rehospitalized, FU IVCmax was ≤2.1 cm (2.1 ± 0.6 and 1.9 ± 0.6; P = .038) and IVCCI >50% at both time points (55 ± 25% and 62 ± 19%; P = NS). FU IVCCI below an optimal cutoff of 42% had modest discrimination alone (c-statistic = 0.73). FU IVCCI <42% was associated with a greater hazard of the outcome independent of admission log B-type natriuretic peptide (adjusted hazard ratio = 6.8; 95% confidence interval 2.4-19.0; P < .001). CONCLUSIONS: Posthospitalization IVCCI assessment with PCUS predicts HF rehospitalization and may identify patients in need of intervention.

Cytomegalovirus infection in heart transplantation: A single center experience.

BACKGROUND: Cytomegalovirus (CMV) infection remains a major complication after heart transplantation with varying prophylaxis strategies employed. We sought to determine the impact of valganciclovir (VGC) duration on the epidemiology of CMV infections after heart transplantation. METHODS: We performed a prospective cohort study of CMV donor (D) or recipient (R) seropositive heart transplant recipients from 2005 to 2012 who completed VGC prophylaxis, ranging from 3 to 12 months according to serostatus and induction immunosuppression. Univariate and multivariate logistic regression was performed. RESULTS: Among 159 heart transplant recipients during the study period, 130 (82%) were eligible for VGC prophylaxis. CMV D/R serostatus was as follows: 24% D+/R-, 30% D+/R+, and 29% D-/R+. 65% and 21% received basiliximab and thymoglobulin induction, respectively, followed by maintenance tacrolimus, mycophenolate mofetil, and prednisone. Twenty-one (16%) recipients suffered CMV infection. There was no association with comorbidities including diabetes mellitus, chronic kidney disease, or mechanical assist devices, nor were there associations with rejection, treatments of rejection, or mortality. When VGC prophylaxis duration was stratified by ≤6 vs ≥12 months, time from heart transplantation to CMV infection was delayed (median 247 vs 452 days, P = .002) but there was no difference in days from VGC discontinuation to onset of CMV infection (median 72 vs 83 days, P = .31). CMV infection occurred most frequently within 6-16 weeks of VGC cessation, and 95% of infections occurred during the 6 months post-prophylaxis period. CONCLUSIONS: Relative to ≤6 months, ≥12 months of VGC did not reduce incidence of CMV infection and only delayed time to onset. 95% of CMV infection occurs within 6 months after cessation of VGC.

Strokes associated with left ventricular assist devices.

Ventricular assist devices (VADs) have improved dramatically over the past several decades but stroke remains a problem. There are multiple etiologies of both ischemic and hemorrhagic strokes associated with VADs. While this problem is yet to be solved, there are continuing efforts at improving the design of VADs to decrease the incidence of stroke and to improve long-term survival in patients requiring mechanical circulatory assistance. The purpose is to review the incidence and underlying causes of stroke in VAD patients.

Invasive fungal infection after heart transplantation: A 7-year, single-center experience.

BACKGROUND: Invasive fungal infections (IFIs) are an infrequent but major complication of heart transplantation (HT). We sought to describe the epidemiology at our institution. METHODS: A prospective cohort study of 159 heart transplant recipients was performed from June 2005 to December 2012. IFIs were defined by European Organization for Research and Treatment of Cancer/Mycoses Study Group criteria. RESULTS: By univariate analysis, Hispanic ethnicity was associated with IFI (P=.01, odds ratio [OR] 7.0, 95% confidence interval [CI] 1.7-27.9). Subsequently, a multivariate logistic regression was performed adjusting for Hispanic ethnicity, age, and gender. Seventeen IFIs were identified, occurring at a median 110 days post HT (interquartile range: 32-411 days). Five IFIs (29% of IFIs and 3.1% of all HT) occurred during the HT hospitalization, with 13 IFIs during the first year (incidence 8.2%). CONCLUSIONS: The cumulative incidence was 10.7%. IFIs were associated with pre- and post-HT vancomycin-resistant Enterococcus colonization and/or infection, post-HT renal replacement therapy, anti-thymocyte globulin induction, and antibody-mediated rejection. There were no associations with diabetes mellitus, desensitization, 2R/3R cellular rejection, treatments for rejection, re-operation, neutropenia, or cytomegalovirus infection. IFIs were associated with death (P=.02, OR 3.9, 95% CI 1.3-12.1) and 1-year mortality (P<.001, OR 9.0, 95% CI 2.3-35.7), but not 3-year mortality. Associations with Hispanic ethnicity must be validated. Optimal strategies for risk reduction and prophylaxis remain undefined.

Use of an intrapericardial, continuous-flow, centrifugal pump in patients awaiting heart transplantation.

BACKGROUND: Contemporary ventricular assist device therapy results in a high rate of successful heart transplantation but is associated with bleeding, infections, and other complications. Further reductions in pump size, centrifugal design, and intrapericardial positioning may reduce complications and improve outcomes. METHODS AND RESULTS: We studied a small, intrapericardially positioned, continuous-flow centrifugal pump in patients requiring an implanted ventricular assist device as a bridge to heart transplantation. The course of investigational pump recipients was compared with that of patients implanted contemporaneously with commercially available devices. The primary outcome, success, was defined as survival on the originally implanted device, transplantation, or explantation for ventricular recovery at 180 days and was evaluated for both noninferiority and superiority. Secondary outcomes included a comparison of survival between groups and functional and quality-of-life outcomes and adverse events in the investigational device group. A total of 140 patients received the investigational pump, and 499 patients received a commercially available pump implanted contemporaneously. Success occurred in 90.7% of investigational pump patients and 90.1% of controls, establishing the noninferiority of the investigational pump (P<0.001; 15% noninferiority margin). At 6 months, median 6-minute walk distance improved by 128.5 m, and both disease-specific and global quality-of-life scores improved significantly. CONCLUSIONS: A small, intrapericardially positioned, continuous-flow, centrifugal pump was noninferior to contemporaneously implanted, commercially available ventricular assist devices. Functional capacity and quality of life improved markedly, and the adverse event profile was favorable. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00751972.

Gene-expression profiling for rejection surveillance after cardiac transplantation.

BACKGROUND: Endomyocardial biopsy is the standard method of monitoring for rejection in recipients of a cardiac transplant. However, this procedure is uncomfortable, and there are risks associated with it. Gene-expression profiling of peripheral-blood specimens has been shown to correlate with the results of an endomyocardial biopsy. METHODS: We randomly assigned 602 patients who had undergone cardiac transplantation 6 months to 5 years previously to be monitored for rejection with the use of gene-expression profiling or with the use of routine endomyocardial biopsies, in addition to clinical and echocardiographic assessment of graft function. We performed a noninferiority comparison of the two approaches with respect to the composite primary outcome of rejection with hemodynamic compromise, graft dysfunction due to other causes, death, or retransplantation. RESULTS: During a median follow-up period of 19 months, patients who were monitored with gene-expression profiling and those who underwent routine biopsies had similar 2-year cumulative rates of the composite primary outcome (14.5% and 15.3%, respectively; hazard ratio with gene-expression profiling, 1.04; 95% confidence interval, 0.67 to 1.68). The 2-year rates of death from any cause were also similar in the two groups (6.3% and 5.5%, respectively; P=0.82). Patients who were monitored with the use of gene-expression profiling underwent fewer biopsies per person-year of follow-up than did patients who were monitored with the use of endomyocardial biopsies (0.5 vs. 3.0, P<0.001). CONCLUSIONS: Among selected patients who had received a cardiac transplant more than 6 months previously and who were at a low risk for rejection, a strategy of monitoring for rejection that involved gene-expression profiling, as compared with routine biopsies, was not associated with an increased risk of serious adverse outcomes and resulted in the performance of significantly fewer biopsies. (ClinicalTrials.gov number, NCT00351559.)

The Accuracy of Initial U.S. Heart Transplant Candidate Rankings.

BACKGROUND: The U.S. heart allocation system ranks candidates with only 6 treatment-based categorical "statuses" and ignores many objective patient characteristics. OBJECTIVES: This study sought to determine the effectiveness of the standard 6-status ranking system and several novel prediction models in identifying the most urgent heart transplant candidates. METHODS: The primary outcome was death before receipt of a heart transplant. The accuracy of the 6-status system was evaluated using Harrell's C-index and log-rank tests of Kaplan-Meier estimated survival by status for candidates listed postpolicy (November 2018 to March 2020) in the Scientific Registry of Transplant Recipients data set. The authors then developed Cox proportional hazards models and random survival forest models using prepolicy data (2010-2017). The predictor variables included age, diagnosis, laboratory measurements, hemodynamics, and supportive treatment at the time of listing. The performance of these models was compared with the candidate's 6-status ranking in the postpolicy data. RESULTS: Since policy implementation, the 6-status ranking at listing has had moderate ability to rank-order candidates (C-index: 0.67). Statuses 4 and 6 had no significant difference in survival (P = 0.80), and status 5 had lower survival than status 4 (P < 0.001). Novel multivariable prediction models derived with prepolicy data ranked candidates correctly more often than the 6-status rankings (Cox proportional hazards model C-index: 0.76; random survival forest model C-index: 0.74). Objective physiologic measurements, such as glomerular filtration rate, had high variable importance. CONCLUSIONS: The treatment-based 6-status heart allocation system has only moderate ability to rank-order candidates by medical urgency. Predictive models that incorporate physiologic measurements can more effectively rank-order heart transplant candidates by urgency.

Cardiac complications of COVID-19: Incidence and outcomes.

BACKGROUND: Coronavirus disease-2019 (COVID-19) has been associated with pre-existing cardiac conditions as well as cardiovascular complications. The incidence rates of cardiac complications, age, and gender differences in this population are unknown. OBJECTIVES: We wanted to study the incidence of cardiac complications and mortality in patients with COVID-19. METHODS: Data from the TriNetX COVID-19 global research network platform was used to identify COVID-19 patients. We compared patients with and without cardiac complications in patients with COVID-19 and obtained survival data. RESULTS: The final cohort was composed of 81,844 patients with COVID-19. Cardiac complications occurred in 9.3% of patients as follows: acute coronary syndromes in 1.3%, heart failure in 4.4%, atrial fibrillation in 4.5%, sinus bradycardia 1.9%, ventricular tachycardia in 0.5% and complete heart block in 0.01%. Mortality was significantly higher in patients with the cardiac complications mentioned (20%) than in those without them (2.9%) (odds ratio 7.2, 95% CI, 6.7-7.7; p < 0.0001). Older males seem to have higher incidence of cardiac complications and mortality. CONCLUSIONS: Patients with COVID-19 who have cardiac complications have a higher risk of mortality when compared to those without cardiac complications.