Outcomes following additional drainage during veno-venous extracorporeal membrane oxygenation: A single-center retrospective study.

Refractory hypoxemia during veno-venous (V-V) extracorporeal membrane oxygenation (ECMO) may require an additional cannula (VV-V ECMO) to improve oxygenation. This intervention includes risk of recirculation and other various adverse events (AEs) such as injury to the lung, cannula malpositioning, bleeding, circuit or cannula thrombosis requiring intervention (i.e., clot), or cerebral injury. During the study period, 23 of 142 V-V ECMO patients were converted to VV-V utilizing two separate cannulas for bi-caval drainage with an additional upper extremity cannula placed for return. Of those, 21 had COVID-19. In the first 24 h after conversion, ECMO flow rates were higher (5.96 vs 5.24 L/min, p = .002) with no significant change in pump speed (3764 vs 3630 revolutions per minute [RPMs], p = .42). Arterial oxygenation (PaO2) increased (87 vs 64 mmHg, p < .0001) with comparable pre-oxygenator venous saturation (61 vs 53.3, p = .12). By day 5, flows were similar to pre-conversion values at lower pump speed but with improved PaO2. Unadjusted survival was similar in those converted to VV-V ECMO compared to V-V ECMO alone (70% [16/23] vs 66.4% [79/119], p = .77). In a mixed effect regression model, any incidence of AEs, demonstrated a negative impact on PaO2 in the first 48 h but not at day 5. VV-V ECMO improved oxygenation with increasing flows without a significant difference in AEs or pump speed. AEs transiently impacted oxygenation. VV-V ECMO is effective and feasible strategy for refractory hypoxemia on VV-ECMO allowing for higher flow rate and unchanged pump speed.

Association of Psychosocial Risk Factors With Quality of Life and Readmissions 1 Year After LVAD Implantation.

BACKGROUND: Among patients with advanced heart failure (HF), treatment with a left ventricular assist device (LVAD) improves health-related quality of life (HRQOL). We investigated the association between psychosocial risk factors, HRQOL and outcomes after LVAD implantation. METHODS: A retrospective cohort (n = 9832) of adults aged ≥ 19 years who received durable LVADs between 2008 and 2017 was identified by using the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS). Patients were considered to have psychosocial risk factors if ≥ 1 of the following were present: (1) substance abuse; (2) limited social support; (3) limited cognitive understanding; (4) repeated nonadherence; and (5) major psychiatric disease. Multivariable logistic and linear regression models were used to evaluate the association between psychosocial risk factors and change in Kansas City Cardiomyopathy Questionnaire (KCCQ)-12 scores from baseline to 1 year, persistently poor HRQOL (KCCQ-12 score < 45 at baseline and 1 year), and 1-year rehospitalization. RESULTS: Among the final analytic cohort, 2024 (20.6%) patients had ≥ 1 psychosocial risk factors. Psychosocial risk factors were associated with a smaller improvement in KCCQ-12 scores from baseline to 1 year (mean ± SD, 29.1 ± 25.9 vs 32.6 ± 26.1; P = 0.015) for a difference of -3.51 (95% confidence interval [CI]: -5.88 to -1.13). Psychosocial risk factors were associated with persistently poor HRQOL (adjusted odds ratio [aOR] 1.35, 95% confidence interval [CI] 1.04-1.74), and 1-year all-cause readmission (adjusted hazard ratio [aHR] 1.11, 95% CI 1.05-1.18). Limited social support, major psychiatric disorder and repeated nonadherence were associated with persistently poor HRQOL, while major psychiatric disorder was associated with 1-year rehospitalization. CONCLUSION: The presence of psychosocial risk factors is associated with lower KCCQ-12 scores and higher risk for readmission at 1 year after LVAD implantation. These associations are statistically significant, but further research is needed to determine whether these differences are clinically meaningful.

Ex vivo lung perfusion in donation after circulatory death: A post hoc analysis of the Normothermic Ex Vivo Lung Perfusion as an Assessment of Extended/Marginal Donors Lungs trial.

OBJECTIVE: Donation after circulatory death (DCD) donors offer the ability to expand the lung donor pool and ex vivo lung perfusion (EVLP) further contributes to this ability by allowing for additional evaluation and resuscitation of these extended criteria donors. We sought to determine the outcomes of recipients receiving organs from DCD EVLP donors in a multicenter setting. METHODS: This was an unplanned post hoc analysis of a multicenter, prospective, nonrandomized trial that took place during 2011 to 2017 with 3 years of follow-up. Patients were placed into 3 groups based off procurement strategy: brain-dead donor (control), brain-dead donor evaluated by EVLP, and DCD donors evaluated by EVLP. The primary outcomes were severe primary graft dysfunction at 72 hours and survival. Secondary outcomes included select perioperative outcomes, and 1-year and 3-years allograft function and quality of life measures. RESULTS: The DCD EVLP group had significantly higher incidence of severe primary graft dysfunction at 72 hours (P = .03), longer days on mechanical ventilation (P < .001) and in-hospital length of stay (P = .045). Survival at 3 years was 76.5% (95% CI, 69.2%-84.7%) for the control group, 68.3% (95% CI, 58.9%-79.1%) for the brain-dead donor group, and 60.7% (95% CI, 45.1%-81.8%) for the DCD group (P = .36). At 3-year follow-up, presence observed bronchiolitis obliterans syndrome or quality of life metrics did not differ among the groups. CONCLUSIONS: Although DCD EVLP allografts might not be appropriate to transplant in every candidate recipient, the expansion of their use might afford recipients stagnant on the waitlist a viable therapy.

Patient Characteristics and Early Clinical Outcomes With Impella 5.5: A Systematic Review and Meta-Analysis.

Data regarding outcomes with Impella 5.5 are limited. The aim of this systematic review and meta-analysis was to summarize patient and treatment characteristics and early clinical outcomes among patients supported by Impella 5.5. A systematic literature search was conducted in PubMed, Scopus, and Cochrane databases from September 2019 to March 2023. Studies reporting outcomes in greater than or equal to 5 patients were included for review. Patient characteristics, treatment characteristics, and early clinical outcomes were extracted. Outcomes included adverse events, survival to hospital discharge, and 30 day survival. Random-effect models were used to estimate pooled effects for survival outcomes. Assessment for bias was performed using funnel plots and Egger's tests. Fifteen studies were included for qualitative review, representing 707 patients. Mean duration of support was 9.9 ± 8.2 days. On meta-analysis of 13 studies reporting survival outcomes, survival to hospital discharge was 68% (95% confidence interval [CI], 58-78%), and 30 day survival was 65% (95% CI, 56-74%) among patients with Impella devices predominantly supported by Impella 5.5 (>60%). There was significant study heterogeneity for these outcomes. Among 294 patients with Impella 5.5 only, survival to discharge was 78% (95% CI, 72-82%) with no significant study heterogeneity. This data present early benchmarks for outcomes with Impella 5.5 as clinical experience with these devices accrues.

Outcomes associated with prolonged ECMO in COVID-19 associated ARDS: A single center experience.

PURPOSE OF STUDY: The COVID-19 pandemic has led to a significant increase in the use of veno-venous extracorporeal membrane oxygenation (V-V ECMO) as a bridge to transplantation versus recovery. Unlike other etiologies of acute respiratory distress syndrome (ARDS), utilization of V-V ECMO in COVID-19 has been associated with longer duration of ECMO support requirements. Our team sought to evaluate outcomes associated with prolonged duration of ECMO support in this patient population. METHODS: Single-center retrospective review of patients who were placed on ECMO due to COVID-19 associated ARDS. Specifically examining outcomes-transplant free survival, mortality and discharge rates-of patients requiring V-V ECMO support for greater than 50 days. RESULTS: The median age of the cohort was 48 years and 13 patients (72%) were males. The median duration of ECMO support was 84 days (IQR 55-106). 11 patients (61%) had right ventricular dysfunction and 13 patients (72%) had pneumothoraces. There was a 33% percent (n = 6) mortality rate within cohort. One patient continues to require ECMO support at time of abstract submission. 11 patients (61%) patients were discharged, of which 3 patients required a lung transplant. SUMMARY: Prolonged V-V ECMO can be associated with comparable outcomes to conventional V-V ECMO runs that are relatively shorter in duration. With availability of device and staffing, prolonged ECMO runs can potentially be justified in a highly selected patient population.

Complex repolarization dynamics in ex vivo human ventricles are independent of the restitution properties.

AIMS: The mechanisms of transition from regular rhythms to ventricular fibrillation (VF) are poorly understood. The concordant to discordant repolarization alternans pathway is extensively studied; however, despite its theoretical centrality, cannot guide ablation. We hypothesize that complex repolarization dynamics, i.e. oscillations in the repolarization phase of action potentials with periods over two of classic alternans, is a marker of electrically unstable substrate, and ablation of these areas has a stabilizing effect and may reduce the risk of VF. To prove the existence of higher-order periodicities in human hearts. METHODS AND RESULTS: We performed optical mapping of explanted human hearts obtained from recipients of heart transplantation at the time of surgery. Signals recorded from the right ventricle endocardial surface were processed to detect global and local repolarization dynamics during rapid pacing. A statistically significant global 1:4 peak was seen in three of six hearts. Local (pixel-wise) analysis revealed the spatially heterogeneous distribution of Periods 4, 6, and 8, with the regional presence of periods greater than two in all the hearts. There was no significant correlation between the underlying restitution properties and the period of each pixel. CONCLUSION: We present evidence of complex higher-order periodicities and the co-existence of such regions with stable non-chaotic areas in ex vivo human hearts. We infer that the oscillation of the calcium cycling machinery is the primary mechanism of higher-order dynamics. These higher-order regions may act as niduses of instability and may provide targets for substrate-based ablation of VF.

Early Tracheostomy May Be Performed Safely in Obese COVID-19 Patients Supported on VV-ECMO.

OBJECTIVE: Obese patients with coronavirus disease 2019 (COVID-19)-associated acute respiratory failure (ARDS) often require prolonged intubation. However, data are sparse regarding optimal tracheostomy timing in obese adults with COVID-19 requiring venovenous extracorporeal membrane oxygenation (VV-ECMO). This study retrospectively describes the course of obese patients with COVID-19 who underwent tracheostomy on VV-ECMO between March 2020 and December 2022. METHODS: There were 62 participants with a median age of 43 (interquartile range [IQR] 33 to 53) years and a median body mass index of 42 (IQR 34 to 50) kg/m2 who received VV-ECMO for COVID-19-associated ARDS. Of those, 42 underwent tracheostomy on VV-ECMO, and 50% (n = 21) of the 42 patients underwent early (within 14 days of initiated ventilatory support) tracheostomy. RESULTS: Among patients who received tracheostomies, the combined respiratory tract and lung parenchymal bleeding rate was 29% (n = 12), but only 7% required surgical intervention for bleeding from the tracheostomy site (n = 3). The hospital length of stay (LOS) was 42 (IQR 36 to 57) days, and mortality rate was 38% (n = 16). Tracheostomy timing was not associated with differences in respiratory tract bleeding, mechanical ventilatory support duration, VV-ECMO support duration, intensive care unit LOS, hospital LOS, mortality, or survival probability. CONCLUSIONS: Although an individualized and holistic approach to clinical decision making continues to be necessary, the findings of this study suggest that early tracheostomy may be performed safely in obese patients with COVID-19 on VV-ECMO.

Higher-Order Dynamics Beyond Repolarization Alternans in Ex-Vivo Human Ventricles are Independent of the Restitution Properties.

Background: Repolarization alternans, defined as period-2 oscillation in the repolarization phase of the action potentials, provides a mechanistic link between cellular dynamics and ventricular fibrillation (VF). Theoretically, higher-order periodicities (e.g., periods 4, 6, 8,...) are expected but have minimal experimental evidence. Methods: We studied explanted human hearts obtained from recipients of heart transplantation at the time of surgery. Optical mapping of the transmembrane potential was performed after staining the hearts with voltage-sensitive fluorescent dyes. Hearts were stimulated at an increasing rate until VF was induced. Signals recorded from the right ventricle endocardial surface prior to induction of VF and in the presence of 1:1 conduction were processed using the Principal Component Analysis and a combinatorial algorithm to detect and quantify higher-order dynamics. Results were correlated to the underlying electrophysiological characteristics as quantified by restitution curves and conduction velocity. Results: A prominent and statistically significant global 1:4 peak (corresponding to period-4 dynamics) was seen in three of the six studied hearts. Local (pixel-wise) analysis revealed the spatially heterogeneous distribution of periods 4, 6, and 8, with the regional presence of periods greater than two in all the hearts. There was no significant correlation between the underlying restitution properties and the period of each pixel. Discussion: We present evidence of higher-order periodicities and the co-existence of such regions with stable non-chaotic areas in ex-vivo human hearts. We infer from the independence of the period to the underlying restitution properties that the oscillation of the excitation-contraction coupling and calcium cycling mechanisms is the primary mechanism of higher-order dynamics. These higher-order regions may act as niduses of instability that can degenerate into chaotic fibrillation and may provide targets for substrate-based ablation of VF.

Tracheal resection and primary reconstruction on venovenous extracorporeal membrane oxygenation.

Cross-table ventilation during tracheal resection via posterolateral thoracotomy presents a technical challenge. With the ubiquity of venovenous extracorporeal membrane oxygenation (VV-ECMO), there is now a safe and feasible alternative for intraoperative respiratory support. Airway surgery on ECMO avoids prolonged periods of apnea or single lung ventilation, allowing patients with poor lung function to undergo surgery. Image-guided femoro-femoral cannulation using a low-dose heparin protocol minimizes the risk of bleeding while uncluttering the surgical field. By eliminating the need to constantly reposition the endotracheal tube, visualization is improved, and the rhythm of the case is maintained, which can shorten the anastomotic time. Here, we present a case where venovenous ECMO and total intravenous anesthesia were used to completely support a patient undergoing major tracheal surgery without the need for cross-table ventilation.

Management and outcomes of heart transplant candidates with bloodstream infection on temporary mechanical circulatory support.

The outcomes and management of bloodstream infection (BSI) in patients on temporary mechanical circulatory support (TMCS) awaiting heart transplant (HT) are poorly understood. We present outcomes of patients on TMCS with BSI (TMCS-I) relative to matched uninfected patients (TMCS-U) and discuss their management. Between January 1, 2013, and April 30, 2023, N = 136 patients were bridged to transplant with TMCS at Emory Transplant Center. Twenty-one (15.4%) patients were TMCS-I. Two (9.5%) had infective endocarditis. Median duration of antimicrobial treatment was 24 days (interquartile range 28.3). All TMCS-I were reactivated for transplant within 48 to 72 hours of negative blood cultures. None developed recurrent BSI. Post-transplant survival did not differ between TMCS-I and TMCS-U (p = 0.38). HT for TMCS-I may be safe as soon as blood cultures clear. Duration of antimicrobial therapy is individualized and depends on the organism, duration of bacteremia, presence of endocarditis, and timing of HT. Additional research is needed to determine optimal duration of treatment.

Transplantation Outcomes with Donor Hearts after Circulatory Death.

BACKGROUND: Data showing the efficacy and safety of the transplantation of hearts obtained from donors after circulatory death as compared with hearts obtained from donors after brain death are limited. METHODS: We conducted a randomized, noninferiority trial in which adult candidates for heart transplantation were assigned in a 3:1 ratio to receive a heart after the circulatory death of the donor or a heart from a donor after brain death if that heart was available first (circulatory-death group) or to receive only a heart that had been preserved with the use of traditional cold storage after the brain death of the donor (brain-death group). The primary end point was the risk-adjusted survival at 6 months in the as-treated circulatory-death group as compared with the brain-death group. The primary safety end point was serious adverse events associated with the heart graft at 30 days after transplantation. RESULTS: A total of 180 patients underwent transplantation; 90 (assigned to the circulatory-death group) received a heart donated after circulatory death and 90 (regardless of group assignment) received a heart donated after brain death. A total of 166 transplant recipients were included in the as-treated primary analysis (80 who received a heart from a circulatory-death donor and 86 who received a heart from a brain-death donor). The risk-adjusted 6-month survival in the as-treated population was 94% (95% confidence interval [CI], 88 to 99) among recipients of a heart from a circulatory-death donor, as compared with 90% (95% CI, 84 to 97) among recipients of a heart from a brain-death donor (least-squares mean difference, -3 percentage points; 90% CI, -10 to 3; P<0.001 for noninferiority [margin, 20 percentage points]). There were no substantial between-group differences in the mean per-patient number of serious adverse events associated with the heart graft at 30 days after transplantation. CONCLUSIONS: In this trial, risk-adjusted survival at 6 months after transplantation with a donor heart that had been reanimated and assessed with the use of extracorporeal nonischemic perfusion after circulatory death was not inferior to that after standard-care transplantation with a donor heart that had been preserved with the use of cold storage after brain death. (Funded by TransMedics; ClinicalTrials.gov number, NCT03831048.).

Beyond Alternans: Detection of Higher-Order Periodicity in Ex-Vivo Human Ventricles Before Induction of Ventricular Fibrillation.

Background: Repolarization alternans, defined as period-2 oscillation in the repolarization phase of the action potentials, is one of the cornerstones of cardiac electrophysiology as it provides a mechanistic link between cellular dynamics and ventricular fibrillation (VF). Theoretically, higher-order periodicities (e.g., period-4, period-8,...) are expected but have very limited experimental evidence. Methods: We studied explanted human hearts, obtained from the recipients of heart transplantation at the time of surgery, using optical mapping technique with transmembrane voltage-sensitive fluorescent dyes. The hearts were stimulated at an increasing rate until VF was induced. The signals recorded from the right ventricle endocardial surface just before the induction of VF and in the presence of 1:1 conduction were processed using the Principal Component Analysis and a combinatorial algorithm to detect and quantify higher-order dynamics. Results: A prominent and statistically significant 1:4 peak (corresponding to period-4 dynamics) was seen in three of the six studied hearts. Local analysis revealed the spatiotemporal distribution of higher-order periods. Period-4 was localized to temporally stable islands. Higher-order oscillations (period-5, 6, and 8) were transient and primarily occurred in arcs parallel to the activation isochrones. Discussion: We present evidence of higher-order periodicities and the co-existence of such regions with stable non-chaotic areas in ex-vivo human hearts before VF induction. This result is consistent with the period-doubling route to chaos as a possible mechanism of VF initiation, which complements the concordant to discordant alternans mechanism. The presence of higher-order regions may act as niduses of instability that can degenerate into chaotic fibrillation.

Epidemiology, management, and clinical outcomes of extrapulmonary Mycobacterium abscessus complex infections in heart transplant and ventricular assist device recipients.

Nontuberculous mycobacteria are emerging pathogens, yet data on the epidemiology and management of extrapulmonary nontuberculous mycobacteria infections in orthotopic heart transplantation (OHT) and ventricular assist device (VAD) recipients are scarce. We retrospectively reviewed records of OHT and VAD recipients who underwent cardiac surgery at our hospital and developed Mycobacterium abscessus complex (MABC) infection from 2013 to 2016 during a hospital outbreak of MABC linked to heater-cooler units. We analyzed patient characteristics, medical and surgical management, and long-term outcomes. Ten OHT patients and 7 patients with VAD developed extrapulmonary M. abscessus subspecies abscessus infection. The median time from presumed inoculation during cardiac surgery to the first positive culture was 106 days in OHT and 29 days in VAD recipients. The most common sites of positive cultures were blood (n = 12), sternum/mediastinum (n = 8), and the VAD driveline exit site (n = 7). The 14 patients diagnosed when alive received combination antimicrobial therapy for a median of 21 weeks, developed 28 antibiotic-related adverse events, and underwent 27 surgeries. Only 8 (47%) patients survived longer than 12 weeks after diagnosis, including 2 patients with VAD who experienced long-term survival after an explantation of infected VADs and OHT. Despite aggressive medical and surgical management, OHT and VAD patients with MABC infection experienced substantial morbidity and mortality.

A textile-reinforced composite vascular graft that modulates macrophage polarization and enhances endothelial cell migration, adhesion and proliferation in vitro.

At the present time, there is no successful off-the-shelf small-caliber vascular graft (<6 mm) for the repair or bypass of the coronary or carotid arteries. In this study, we engineer a textile-reinforced hydrogel vascular graft. The textile fibers are circularly knitted into a flexible yet robust conduit to serve as the backbone of the composite vascular graft and provide the primary mechanical support. It is embedded in the hydrogel matrix which seals the open structure of the knitted reinforcement and mediates cellular response toward a faster reendothelialization. The mechanical properties of the composite vascular graft, including bursting strength, suture retention strength and radial compliance, significantly surpass the requirement for the vascular graft application and can be adjusted by altering the structure of the textile reinforcement. The addition of hydrogel matrix, on the other hand, improves the survival, adhesion and proliferation of endothelial cells in vitro. The composite vascular graft also enhances macrophage activation and upregulates M1 and M2 related gene expression, which further improves the endothelial cell migration that might favor the reendothelialization of the vascular graft. Taken together, the textile-reinforced hydrogel shows it potential to be a promising scaffold material to fabricate a tissue engineered vascular graft.

Improved clinical outcomes associated with the Impella 5.5 compared to the Impella 5.0 in contemporary cardiogenic shock and heart failure patients.

A redesigned surgically implanted heart pump incorporates several design changes from the prior device generation, but no published comparative data demonstrate if these changes translate to improved outcomes. We retrospectively compared clinical characteristics and outcomes, drawn from an FDA-mandated QA database, for contemporary patients treated with the Impella 5.5 or Impella 5.0 for acute myocardial infarction complicated by cardiogenic shock (AMICS), cardiomyopathy, or postcardiotomy cardiogenic shock (PCCS). A total of 1238 patients at 290 US sites were included for analysis. Patients receiving the Impella 5.5 had significantly higher survival through explant (i.e., successfully weaned or bridged to heart replacement therapy) than those receiving the Impella 5.0 in all 3 settings: AMICS (70.5% vs 56.8%; p = 0.005), cardiomyopathy (88.1% vs 76.9%; p = 0.001), and PCCS (76.1% vs 55.7%; p = 0.003). Duration of support was significantly longer for Impella 5.5 patients with AMICS (9.2 vs 6.1 days; p = 0.008) and cardiomyopathy (10.7 vs 8.1 days; p < 0.001).

The Society of Thoracic Surgeons Adult Cardiac Surgery Database: 2022 Update on Outcomes and Research.

The Society of Thoracic Surgeons Adult Cardiac Surgery Database is the most mature and comprehensive cardiac surgery database. It is one of the most respected clinical data registries in health care, providing accurate risk-adjusted benchmarks, a foundation for quality measurement and improvement activities, and the ability to perform novel research. This report encompasses data from the years 2020 and 2021 and is the seventh in a series of reports that provide updated volumes, outcomes, database-related developments, and research summaries using the Adult Cardiac Surgery Database.

"Pushing Geographic Boundaries: Interfacility transport and remote extracorporeal membrane oxygenation cannulation of patients during COVID-19 pandemic".

Amidst the pandemic, geographical boundaries presented challenges to those in need of higher levels of care from referral centers. Authors sought to evaluate potential predictors of treatment success; assess our transport and remote cannulation process; and identify transport associated complications.Retrospective series of critically ill adults with COVID-19 transferred by our Extracorporeal Membrane Oxygenation (ECMO) team 24 March 2020 through 8 June 2021. Descriptive statistics and associated interquartile ranges (IQR) were used to summarize the data.Sixty-three patients with COVID associated acute respiratory distress syndrome (ARDS) requiring ECMO support were admitted to our ECMO center. Mean age was 44 years old (SD 12; IQR 36-56). 59% (n = 37) of patients were male. Average body mass index was 39.7 (SD 11.3; IQR 31-48.5). Majority of patients (77.8%; n = 35) had severe ARDS. Predictors of treatment success were not observed.Transport distances ranged from 2.2 to 236 miles (median 22.5 miles; IQR 8.3-79); round trip times from 18 to 476 min (median 83 min; IQR 44-194). No transport associated complications occurred. Median duration of ECMO support was 17 days (IQR 9.5-34.5). Length of stay in the Intensive Care Unit (median 36 days; IQR 17-49) and hospital (median 39 days; IQR 25-57) varied. Amongst those discharged, 60% survived.