Left ventricle unloading strategies in ECMO: A single-center experience.

INTRODUCTION: Extracorporeal membrane oxygenation (ECMO) is a life-saving technology capable of restoring perfusion but is not without significant complications that limit its realizable therapeutic benefit. ECMO-induced hemodynamics increase cardiac afterload risking left ventricular distention and impaired cardiac recovery. To mitigate potentially harmful effects, multiple strategies to unload the left ventricle (LV) are used in clinical practice but data supporting the optimal approach is presently lacking. MATERIALS & METHODS: We reviewed outcomes of our ECMO population from September 2015 through January 2019 to determine if our LV unloading strategies were associated with patient outcomes. We compared reactive (Group 1, n = 30) versus immediate (Group 2, n = 33) LV unloading and then compared patients unloaded with an Impella CP (n = 19) versus an intra-aortic balloon pump (IABP, n = 16), analyzing survival and ECMO-related complications. RESULTS: Survival was similar between Groups 1 and 2 (33 vs 42%, P = .426) with Group 2 experiencing more clinically-significant hemorrhage (40 vs. 67%, P = .034). Survival and ECMO-related complications were similar between patients unloaded with an Impella versus an IABP. However, the Impella group exhibited a higher rate of survival (37%) than predicted by their median SAVE score (18%). DISCUSSION: Based on this analysis, reactive unloading appears to be a viable strategy while venting with the Impella CP provides better than anticipated survival. Our findings correlate with recent large cohort studies and motivate further work to design clinical guidelines and future trial design.

The impact of hepatitis C viremic donor lung allograft characteristics on post-transplantation outcomes.

BACKGROUND: There is a low utilization rate of donated donor lungs. Historically, transplantation of lungs from hepatitis C-viremic donors to hepatitis C (HCV) negative recipients was avoided due to concern for worse graft survival. In the past few years with the advent of direct acting antiviral (DAA) therapy, there are emerging data suggesting the safety and efficacy of transplanting thoracic organs from HCV-viremic donors. This study assessed the differences in donor characteristics and allograft-specific clinical features at the time of organ offer and investigated whether these variables differed in HCV-viremic versus HCV-negative donors and impacted recipient outcomes. METHODS: We conducted a single-center, retrospective cohort study of adult patients who underwent a lung transplant at Brigham and Women's Hospital between March 2017 and October 2018. Patients were stratified based on their donor HCV status (HCV-viremic versus HCV-negative). Donor and allograft-specific characteristics and clinical features including chest imaging and bronchoscopy reports, respiratory cultures, and the donor's oxygenation as measured by the arterial partial pressure of oxygen (PaO2) were collected as well as recipient baseline characteristics and transplant outcomes. RESULTS: During the study period, 42 and 57 lung transplants were performed from HCV-viremic and HCV-negative donors, respectively. Donor age was similar in both cohorts. More HCV-viremic donors died from drug intoxication (71% versus 19%, P=0.0001) and had a history of cigarette use (83% versus 5%, P=0.0001) and drug use (76% versus 49%, P=0.007). There were differences in the baseline recipient characteristics including a lower median lung allocation score in the HCV-viremic cohort. The organ-specific clinical characteristics including the terminal PaO2, chest imaging and bronchoscopy findings, and evidence of pulmonary infection were similar between the two cohorts. The recipient outcomes overall were excellent and did not differ significantly in both cohorts in terms of graft and patient survival at 6 and 12 months. CONCLUSIONS: Despite a greater proportion of HCV-viremic donors being increased risk with a history of drug and cigarette use and having died as a result of drug intoxication, the quality of the HCV-viremic donor organs did not differ from the HCV-negative donor organs or impact graft and recipient survival. Due to an increasing number of transplants from increased risk donors and in order to develop safe and effective protocols to perform lung transplants from HCV-infected donors, further characterization of the donor and allograft-specific clinical features and longer-term recipient outcomes is greatly needed.

Sternotomy versus thoracotomy lung transplantation: key tips and contemporary results.

The purpose of this report is to provide an updated description of the technique of bilateral sequential lung transplant via median sternotomy. A sternotomy provides the advantage of less morbidity than the clamshell incision, as well as exposure to perform mechanical circulatory support and concurrent cardiac procedures. Our experience shows that lung transplantation via a midline sternotomy can be done with equivalent to better short-term outcomes than a clamshell incision, including earlier extubation and fewer transfusions. Familiarity with this technique is important for all surgeons managing end-stage lung disease.

Comparison of heart transplant outcomes between recipients with pulsatile- vs continuous-flow LVAD.

OBJECTIVE: Continuous-flow (CF) left ventricular assist devices (LVADs) have replaced pulsatile flow (PF) LVADs irrespective of concerns from the physiologic changes/morbidity secondary to lack of pulsatility. Data comparing posttransplant outcomes in patients with CF vs PF LVADs are limited and conflicting. We used the Organ Procurement and Transplant Network database to compare posttransplant outcomes between CF and PF LVAD patients. METHODS: From 1 January 2005 to 31 December 2011, 3449 adult patients underwent primary heart alone transplantation. The cohort was restricted to 2741 recipients with LVAD at the time of transplant and divided into two groups: PF (Heartmate XVE) (n = 705) and CF (Heartmate II, HeartWare HVAD, and Jarvik 2000) (n = 2036). Endpoints were 30-day freedom from graft failure, 1-, and 5-year patient survival. Propensity score matching identified 705 pairs for adjusted comparisons. RESULTS: Among propensity-matched patients, 30-day freedom from graft failure after heart transplantation (PF = 94.8% vs CF = 95.2%, P > .7), and 1-, and 5-year patient survival (PF; 87.5% vs CF; 88.9%, P = .4, and PF;75.7% vs CF;77.5%, P = .3) were not different. CONCLUSION: Survival and freedom from graft failure after heart transplantation is similar between CF and PF LVADs. These findings are relevant as the use of CF devices increases despite physiologic changes related to the absence of pulsatility.

Cardiac hemi-autotransplantation as a new approach to resect complex left atrial neoplasms.

Here, we describe cardiac hemi-autotransplantation as a novel technique to mobilize the heart substantially, facilitating resection of complex left atrial paraganglioma with negative margins in a young patient.

SUPERIOR SVG: no touch saphenous harvesting to improve patency following coronary bypass grafting (a multi-Centre randomized control trial, NCT01047449).

BACKGROUND: Single centre studies support No Touch (NT) saphenous vein graft (SVG) harvesting technique. The primary objective of the SUPERIOR SVG study was to determine whether NT versus conventional (CON) SVG harvesting was associated with improved SVG patency 1 year after coronary artery bypass grafting surgery (CABG). METHODS: Adults undergoing isolated CABG with at least 1 SVG were eligible. CT angiography was performed 1-year post CABG. Leg adverse events were assessed with a questionnaire. A systematic review was performed for published NT graft patency studies and results aggregated including the SUPERIOR study results. RESULTS: Two hundred and-fifty patients were randomized across 12-centres (NT 127 versus CON 123 patients). The primary outcome (study SVG occlusion or cardiovascular (CV) death) was not significantly different in NT versus CON (NT: 7/127 (5.5%), CON 13/123 (10.6%), p = 0.15). Similarly, the proportion of study SVGs with significant stenosis or total occlusion was not significantly different between groups (NT: 8/102 (7.8%), CON: 16/107 (15.0%), p = 0.11). Vein harvest site infection was more common in the NT patients 1 month postoperatively (23.3% vs 9.5%, p < 0.01). Including this study's results, in a meta-analysis, NT was associated with a significant reduction in SVG occlusion, Odds Ratio 0.49, 95% Confidence Interval 0.29-0.82, p = 0.007 in 3 randomized and 1 observational study at 1 year postoperatively. CONCLUSIONS: The NT technique was not associated with improved patency of SVGs at 1-year following CABG while early vein harvest infection was increased. The aggregated data is supportive of an important reduction of SVG occlusion at 1 year with NT harvesting. TRIAL REGISTRATION: NCT01047449 .

Heart and Lung Transplants from HCV-Infected Donors to Uninfected Recipients.

BACKGROUND: Hearts and lungs from donors with hepatitis C viremia are typically not transplanted. The advent of direct-acting antiviral agents to treat hepatitis C virus (HCV) infection has raised the possibility of substantially increasing the donor organ pool by enabling the transplantation of hearts and lungs from HCV-infected donors into recipients who do not have HCV infection. METHODS: We conducted a trial involving transplantation of hearts and lungs from donors who had hepatitis C viremia, irrespective of HCV genotype, to adults without HCV infection. Sofosbuvir-velpatasvir, a pangenotypic direct-acting antiviral regimen, was preemptively administered to the organ recipients for 4 weeks, beginning within a few hours after transplantation, to block viral replication. The primary outcome was a composite of a sustained virologic response at 12 weeks after completion of antiviral therapy for HCV infection and graft survival at 6 months after transplantation. RESULTS: A total of 44 patients were enrolled: 36 received lung transplants and 8 received heart transplants. The median viral load in the HCV-infected donors was 890,000 IU per milliliter (interquartile range, 276,000 to 4.63 million). The HCV genotypes were genotype 1 (in 61% of the donors), genotype 2 (in 17%), genotype 3 (in 17%), and indeterminate (in 5%). A total of 42 of 44 recipients (95%) had a detectable hepatitis C viral load immediately after transplantation, with a median of 1800 IU per milliliter (interquartile range, 800 to 6180). Of the first 35 patients enrolled who had completed 6 months of follow-up, all 35 patients (100%; exact 95% confidence interval, 90 to 100) were alive and had excellent graft function and an undetectable hepatitis C viral load at 6 months after transplantation; the viral load became undetectable by approximately 2 weeks after transplantation, and it subsequently remained undetectable in all patients. No treatment-related serious adverse events were identified. More cases of acute cellular rejection for which treatment was indicated occurred in the HCV-infected lung-transplant recipients than in a cohort of patients who received lung transplants from donors who did not have HCV infection. This difference was not significant after adjustment for possible confounders. CONCLUSIONS: In patients without HCV infection who received a heart or lung transplant from donors with hepatitis C viremia, treatment with an antiviral regimen for 4 weeks, initiated within a few hours after transplantation, prevented the establishment of HCV infection. (Funded by the Mendez National Institute of Transplantation Foundation and others; DONATE HCV ClinicalTrials.gov number, NCT03086044.).

Posttransplant Lymphoproliferative Disorders in Epstein-Barr Virus Donor Positive/Recipient Negative Lung Transplant Recipients.

BACKGROUND: Epstein-Barr virus (EBV) donor positive/recipient negative (D+/R-) status is a significant risk factor for posttransplant lymphoproliferative disorder (PTLD) in lung transplant. There are, however, no studies that identify the risk factors for PTLD in the EBV D+/R- lung transplant population to guide the decision to proceed with an EBV-positive donor. METHODS: This was a retrospective cohort study of adults listed in the Scientific Registry of Transplant Recipients between May 5, 2005, and August 31, 2016. Cox proportional hazards models were used to assess the impact of EBV D+/R- status on the development of PTLD, the impact of PTLD on survival, and survival differences between EBV D+/R- and EBV D-/R- recipients. RESULTS: The incidence of PTLD was 6.2% (79 of 1,281) versus 1.4% (145 of 10,352) in EBV D+/R- versus all other recipients (adjusted odds ratio 4.0; 95% confidence interval: 2.8 to 5.9, p < 0.001). Among EBV D+/R- recipients, age less than 40 years and white race were associated with PTLD. The EBV D+/R- patients who had PTLD had increased adjusted risk of death (hazard ratio 1.91; 95% confidence interval: 1.35 to 2.71; p < 0.001). Compared with EBV D+/R- recipients, EBV D-/R- recipients did not have improved adjusted survival (hazard ratio 0.82; 95% confidence interval: 0.57 to 1.18; p = 0.30). CONCLUSIONS: Despite increased rates of PTLD and associated mortality in the EBV D+/R- population, EBV seronegative patients did not have worse mortality when transplanted with lungs from EBV seropositive donors compared with lungs from EBV seronegative donors. Consideration should be given for close monitoring for PTLD among EBV D+/R- recipients, particularly those who are white and less than 40 years of age.

Impact of concomitant mitral valve repair for severe mitral regurgitation at the time of continuous-flow left ventricular assist device insertion.

OBJECTIVES: Mitral regurgitation (MR) is common in patients with end-stage heart failure. We assessed the effect of performing concomitant mitral valve repair during continuous-flow left ventricular assist device (CF-LVAD) implantation in patients with severe preoperative MR. METHODS: We performed a single-centre, retrospective review of all patients who underwent CF-LVAD implantation between December 1999 and December 2013 (n = 469). Patients with severe preoperative MR (n = 78) were identified and then stratified according to whether they underwent concomitant valve repair. Univariate and survival analyses were performed, and multivariable regression was used to determine predictors of survival. RESULTS: Of the 78 patients with severe MR, 21 underwent valve repair at the time of CF-LVAD implantation (repair group) and 57 did not (non-repair group). A comparison of the 2 groups showed significant differences between groups: INTERMACS I 16.985 vs 9.52%, (P = 0.039), cardiopulmonary bypass time 82.09 vs 109.4 min (P = 0.0042) and the use of HeartMate II 63.16 vs 100% (P = 0.001). Survival analysis suggested trends towards improved survival and a lower incidence of heart failure-related readmissions in the repair group. Multivariable regression analysis showed no significant independent predictors of survival (mitral valve repair: odds ratio 0.4, 95% confidence interval 0.8-1.5; P = 0.2). CONCLUSIONS: Despite the lack of statistical significance, trends towards improved survival and a lower incidence of heart failure events suggest that mitral valve repair may be beneficial in patients undergoing CF-LVAD implantation. Given the known relationship between severe MR and mortality, further study is encouraged to confirm the value of mitral valve repair in these patients.

The incremental benefit of non-pulmonary vein left atrial ablation in patients undergoing a repeat persistent atrial fibrillation ablation procedure.

PURPOSE: Atrial fibrillation (AF) recurrence after an initial persistent AF ablation procedure is high, frequently resulting in the need for a repeat AF ablation procedure. Guidance on the optimal strategy for repeat procedures is non-existent. The objective of this study was to compare the freedom from recurrent atrial arrhythmia associated with two strategies for repeat persistent AF ablation procedure: (1) pulmonary vein re-isolation alone and (2) non-pulmonary vein LA ablation in addition to pulmonary vein re-isolation. METHODS: A retrospective multi-center case-controlled study was undertaken. Time-to-recurrent AF with each strategy was assessed using Kaplan-Meier curves. A Cox proportional-hazards regression model was used to determine time-dependent predictors of recurrent AF after the repeat procedure in the entire cohort. RESULTS: Ninety-eight patients were included in the cohort-39 patients who did not undergo additional LA ablation and 59 patients who had did. AF after the repeat procedure occurred in 38 % of the cohort during a mean follow-up of 18 ± 11 months. Additional LA ablation at the repeat procedure was not associated with a less arrhythmia recurrence (HR = 1.55, p = 0.28). The only variable associated with arrhythmia recurrence after the repeat procedure was additional LA ablation during the initial ablation procedure (HR = 4.13, p = 0.005). CONCLUSIONS: LA ablation in addition to pulmonary vein re-isolation during a repeat persistent AF ablation procedure was not associated with reduced arrhythmia recurrence after a repeat persistent AF ablation procedure.