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.).

Design and characteristics of the prophylactic intra-operative ventricular arrhythmia ablation in high-risk LVAD candidates (PIVATAL) trial.

BACKGROUND: The use of a Left Ventricular Assist Device (LVAD) in patients with advanced heart failure refractory to optimal medical management has progressed steadily over the past two decades. Data have demonstrated reduced LVAD efficacy, worse clinical outcome, and higher mortality for patients who experience significant ventricular tachyarrhythmia (VTA). We hypothesize that a novel prophylactic intra-operative VTA ablation protocol at the time of LVAD implantation may reduce the recurrent VTA and adverse events postimplant. METHODS: We designed a prospective, multicenter, open-label, randomized-controlled clinical trial enrolling 100 patients who are LVAD candidates with a history of VTA in the previous 5 years. Enrolled patients will be randomized in a 1:1 fashion to intra-operative VTA ablation (n = 50) versus conventional medical management (n = 50) with LVAD implant. Arrhythmia outcomes data will be captured by an implantable cardioverter defibrillator (ICD) to monitor VTA events, with a uniform ICD programming protocol. Patients will be followed prospectively over a mean of 18 months (with a minimum of 9 months) after LVAD implantation to evaluate recurrent VTA, adverse events, and procedural outcomes. Secondary endpoints include right heart function/hemodynamics, healthcare utilization, and quality of life. CONCLUSION: The primary aim of this first-ever randomized trial is to assess the efficacy of intra-operative ablation during LVAD surgery in reducing VTA recurrence and improving clinical outcomes for patients with a history of VTA.

Interaction between ischemic time and donor age under the new donor heart allocation system: Effect on post-transplant survival.

BACKGROUND: Ischemic time (IT) under the new heart transplant (HTx) allocation system has increased compared to the old system. We investigated the effect of IT and donor age on post-HTx survival. METHODS: The United Network for Organ Sharing (UNOS) database was analyzed to identify adult HTx between October 2015 and August 2020. Recipients were stratified by donor age, transplantation era, and IT. Kaplan-Meier and log-rank tests were used to compare 180-day post-HTx mortality. Cox proportional hazards modeling and propensity score matching were performed to adjust for confounders. RESULTS: Under the new system (N = 3654), IT≥4 h led to decreased survival compared to IT < 4 h (91.4% vs. 93.7%; P = .02), although this decrease was undetectable among those with donors ≥39 years old (90.4% vs. 91.1%; P = .73). IT≥4 h led to decreased survival with donors < 39 years old (91.7% vs. 94.6%; P < .01). Under the old system (N = 5987), IT≥4 h resulted in decreased survival (89.8% vs. 93.9%; P < .01), including with donors ≥39 years old (86.9% vs. 92.4%; P < .01). CONCLUSIONS: IT≥4 h remains a risk for post-HTx mortality under the new system. However, the magnitude of this effect is blunted when donor age is ≥39 years, likely secondary to increased allocation of these organs to lower status, more stable recipients.

Using aortic arch short axis views during transesophageal echocardiographic examination facilitates right ventricular assist device imaging.

Given the increased need for mechanical circulatory support and subsequent development of right ventricular assist devices (RVAD), appropriate imaging needs to be described to facilitate care in patients with cardiogenic shock and heart failure. We present three cases in which the upper esophageal aortic arch short axis (UE AA SAX) view on transesophageal echocardiography (TEE) was utilized to effectively image RVADs: to confirm normal positioning, to detect and guide repositioning, and to visualize malfunction. These cases support the importance of the UE AA SAX TEE view in RVAD outflow imaging and, when obtainable, should be included in routine RVAD assessment.

Echocardiographic Assessment of Left Ventricular Assist Device Outflow Velocity During Percutaneous Decommissioning.

Left ventricular assist devices (LVADs) have been used as an effective therapeutic option in patients with advanced heart failure, either as a bridge to transplantation or, in some patients, as a bridge to recovery. LVAD withdrawal with ventricular recovery represents the optimal outcome for patients previously implanted with an LVAD. In this E-Challenge, the authors present a case of percutaneous decommissioning of an LVAD, in which TEE provided critical, real-time perioperative evaluation. The authors also review the current perspectives on LVAD decommissioning in terms of patient selection and surgical techniques.

The Convergent Procedure: A Unique Multidisciplinary Hybrid Treatment of Atrial Fibrillation.

The convergent procedure is a hybrid ablation treatment for atrial fibrillation. It is increasingly considered as a management option for patients with persistent and long-standing atrial fibrillation. It consists of surgical ablation of the posterior left atrium through a minimally invasive closed-chest approach followed by endocardial catheter ablation. It is increasingly performed with concurrent epicardial occlusion of the left atrial appendage with a video-assisted thoracoscopic technique to physically and electrically isolate the left atrial appendage. This article provides an overview of a multidisciplinary approach to the convergent procedure, with concurrent thoracoscopic closure of the left atrial appendage, with an emphasis on perioperative management at a single institution. It provides a literature review of procedural outcomes, current data limitations, and future considerations.

Untwist the twist: instant hemodynamic improvement in known HeartMate 3 complication.

The HeartMate 3 [HM3 (Abbott, Abbott Park, Illinois)] is a left-ventricular assist device (LVAD) with excellent clinical results. Outflow graft occlusion as a complication secondary to outflow graft twisting was reported to occur in 1.6% within the MOMENTUM 3 trial. The anti-twist metal clip or modified bend relief is made to prevent this complication currently, however, there remain large numbers of early implanted HM3 which may develop this complication. There are limited reports illustrating diagnosis, surgical repair, and post-repair hemodynamic changes of these complications. Thus, we present a case of successful diagnosis and surgical repair of an outflow graft twist. Simple procedure through thoracotomy without cardiopulmonary bypass provides significant immediate hemodynamic improvement.

Left thoracotomy vs full sternotomy for centrifugal durable LVAD implantation: 1-year outcome comparison post-LVAD and post-heart transplantation.

Left ventricular assist device (LVAD) implantations have traditionally been approached through a full median sternotomy (FS). Recently, a minimally invasive left thoracotomy (LT) approach has been popularized. This study sought to compare the outcomes of FS and LT patients post-primary LVAD implantation and post-subsequent heart transplant (HT). This was a single-center retrospective study. 83 patients who underwent primary centrifugal durable LVAD implantation from January 2014 to June 2018 were included (FS, n = 41; LT, n = 42). 41 patients had a subsequent HT (FS, n = 19; LT, n = 22). Pre-operative patient demographics, intraoperative variables, post-operative 1-year survival, length of hospital stay, complications, and outcomes for LVAD implantation and following HT were analyzed. Intraoperative data showed that the LT group had a 23.4% longer mean LVAD implant surgical time (p < 0.01). One-year post-LVAD survival was similar between the two groups (p = 0.05). Complication rates, with the exception of the rate of hemorrhagic stroke (p = 0.04) post-LVAD implant were similar. One-year survival post-HT was similar between groups (p = 0.35). Complication rates and mean length of hospital stay were also similar (p = 1.0) post-HT. Our study demonstrated that LT approach does not negatively affect post-LVAD implantation or post-HT outcomes. Further, larger studies may determine more detailed effects of LT approach.

Timing and Trends of Right Atrial Pressure and Risk of Right Heart Failure After Left Ventricular Assist Device Implantation.

BACKGROUND: Elevated right atrial pressure (RAP) is associated with poor outcomes after left ventricular assist device (LVAD) implantation. However, the optimal time for RAP measurement and the importance of resolution of right heart congestion prior to LVAD implantation remain unclear. METHODS AND RESULTS: We performed a retrospective cohort study of 134 consecutive LVAD recipients from our institution. Congestion was defined as RAP ≥ 14 mmHg and was assessed at hospital admission and implant. The primary outcome was death or right ventricular assist device (RVAD) implantation. When stratified by congestion status at admission, congested and non-congested patients had similar event-free survival rates (hazard ratio [HR]: 1.2, 95% confidence interval [CI]: 0.6-2.6). However, when stratified at implant, congested patients had a higher rate death or RVAD implantation (HR: 2.5, 95% CI: 1.1-5.6). Patients were then divided into 4 groups based on their trajectory of congestion status: no congestion, resolved congestion, new congestion, or persistent congestion. Patients with no congestion and resolved congestion had similar outcomes, whereas patients with persistent congestion had a markedly increased rate of death or RVAD implantation (HR: 3.1, 95% CI: 1.3-7.6). CONCLUSION: RAP at LVAD implantation is more strongly associated with postoperative outcomes than admission RAP. Patients not responsive to decongestive therapies, with persistently elevated RAP, represent a high-risk cohort for adverse outcomes following LVAD implantation.

A case series: the outcomes, support duration, and graft function recovery after VA-ECMO use in primary graft dysfunction after heart transplantation.

Primary graft dysfunction (PGD) is a rare complication associated with high mortality after heart transplantation, which may require veno-arterial extra-corporeal membrane oxygenation (VA-ECMO) support. A standardized definition for PGD was developed by the International Society of Heart and Lung Transplantation in 2014. Due to limited reports using this definition, the detailed outcomes after VA-ECMO support remain unclear. Therefore, we retrospectively analyzed our single-center outcomes of PGD following VA-ECMO support. Between September 2014 and August 2018, 160 patients underwent heart transplantation in our single center. Nine PGD patients required VA-ECMO support, with an incidence of 5.6%. Pre-operative recipient/donor demographics, intra-operative variables, timing of VA-ECMO initiation and support duration, graft function recovery during 30 days after heart transplant, VA-ECMO complications, and survival were analyzed. The indication for VA-ECMO support was biventricular failure for all nine patients. Six patients had severe PGD requiring intra-operative VA-ECMO, while two patients had moderate PGD and one patient had mild PGD requiring post-operative VA-ECMO. All cohorts were successfully decannulated in a median of 10 days. Survival to discharge rate was 88.9%. One-year survival rate was 85.7%. Left ventricular ejection fraction recovered to normal within 30 days in all PGD patients. Our study showed VA-ECMO support led to high survival and timely graft function recovery in all cohorts. Further larger research can clarify the detailed effects of VA-ECMO support which may lead to standardized indication of VA-ECMO support for PGD patients.

The Neutrophil-Lymphocyte Ratio and Survival During Left Ventricular Assist Device Support.

BACKGROUND: Systolic heart failure (HF) is a low-grade systemic inflammatory state. Neutrophil-lymphocyte ratio (NLR) is a nonspecific inflammatory marker with prognostic value in HF. We aimed to determine the relationship between NLR and mortality during left ventricular assist device (LVAD) support. METHODS AND RESULTS: We retrospectively reviewed LVAD recipients implanted in the years 2010-2018. NLR was recorded before LVAD implantation and at intervals during LVAD support; pre-LVAD and 90-day LVAD NLRs were compared. Cox proportional hazard models were constructed to study the impact of NLR, both before LVAD implantation and at 90 days with LVAD, on mortality during subsequent LVAD support. Among 301 subjects, the median pre-LVAD NLR was 4.7 (interquartile range 3.0-8.0). Higher pre-LVAD NLR was independently associated with increased mortality during a median 324 days of LVAD support (adjusted hazard ratio [HR] 1.03, 95% confidence interval [CI] 1.01-1.06; P = .012, adjusted for pre-LVAD age, HF etiology, white blood count, hemoglobin, blood urea nitrogen, and sodium). After LVAD implantation, the NLR rose initially and then plateaued lower by day 90. Despite the mean decrease, higher 90-day LVAD NLR remained independently associated with increased mortality (adjusted HR 1.06, 95% CI 1.01-1.13; P = .033, stratified by early infection events). CONCLUSIONS: Higher pre-LVAD NLR is independently associated with mortality during LVAD support. NLR improves during LVAD support, but even accounting for early infections, a higher NLR at day 90 remains associated with subsequent mortality.

Postoperative bridging anticoagulation and left ventricular assist system thrombosis.

Reduced emphasis on early postoperative bridging anticoagulation is one explanation for the increased incidence of HeartMate II (HM II) pump thrombosis. We conducted a single-center analysis of initial postoperative anticoagulation practices and their impact on the incidence of HM II pump thrombosis. Data was collected on 105 patients undergoing primary HM II implant from 2009 to 2014. A parenteral bridge was defined as use of parenteral anticoagulation prior to attainment of an international normalized ratio ≥ 2 on warfarin. A parenteral bridge was further characterized as early if initiated ≤ 3 days of implant and therapeutic if a manufacturer-specified goal partial thromboplastin time (PTT) was achieved during each of the first 3 days of administration. Pump thrombosis was "suspected" based upon suggestive clinical parameters leading to hospital admission with parenteral anticoagulant administration and "confirmed" by direct visualization of thrombus in the device. A majority of patients (70%) were treated with an initial parenteral bridge, which was started within 3 days of device implantation in 68% of cases. Therapeutic PTT levels were achieved in 52% of patients treated with a parenteral bridge. Patients who were bridged had lower Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profiles (p = 0.039) and longer intensive care unit stay (p = 0.005). Pump thrombosis was suspected in 25% and confirmed in 13% of patients within 6 months of implant. Point estimates of pump thrombosis incidence demonstrated a lower event rate at 6 months in patients who received a therapeutic bridge (15.8%, 95% CI 6.3-29.1% for suspected; 7.9%, 95% CI 2.0-19.3% for confirmed) compared to those who did not receive a therapeutic bridge (29.9%, CI 19.3-41.1% for suspected; 16.4%, 95% CI 8.7-26.3% for confirmed). This trend was not sustained at 12 and 24 months. Cumulative incidence analyses showed no significant difference in the overall incidence of pump thrombosis between patients who did and did not receive a parenteral bridge. In patients undergoing HM II implantation, the use of initial postoperative parenteral bridging anticoagulation is common but frequently sub-therapeutic. Use of a parenteral bridge reaching therapeutic targets may decrease the 6-month but not the overall incidence of pump thrombosis.

Acute Presentation of Bioprosthetic Mitral Valve Thrombosis in a Patient on Venoarterial Extracorporeal Membranous Oxygenation.

The management of patients presenting with bioprosthetic valve thrombosis presents a major clinical challenge from a diagnostic and management standpoint. This patient population becomes especially challenging to manage when presenting with cardiogenic shock and additional risks for bleeding. In this clinical conference, the authors present the case of a 64-year-old male who developed intraoperative bioprosthetic mitral valve thrombosis and cardiogenic shock necessitating support with venoarterial extracorporeal membrane oxygenation. The discussion focuses on the diagnostic challenges with transesophageal echocardiography and the difficulty in determining the proper approach to systemic anticoagulation.

Left Ventricular Assist Device Thrombosis Is Associated With an Increase in the Systolic-to-Diastolic Velocity Ratio Measured at the Inflow and Outflow Cannulae.

OBJECTIVE: To determine whether the ratio of peak systolic-to-nadir diastolic velocity (S/D ratio) measured using Doppler at the left ventricular assist device (LVAD) inflow and outflow cannulae is associated with pump thrombosis and to determine whether there is an absolute decrease in the diastolic cannula velocities in LVAD thrombosis. DESIGN: Retrospective chart review. SETTING: University hospital. PARTICIPANTS: Patients who underwent LVAD exchange. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Transesophageal echocardiograms were reviewed from all patients with the HeartMate II device (Thoratec Corporation, Pleasanton, CA) over a 6-year period and who underwent LVAD exchange for pump thrombosis. The following 3 time points were evaluated: (1) initial LVAD placement (prethrombosis), (2) thrombosis, and (3) exchanged LVAD placement (postthrombosis). Systolic and diastolic flow velocities were examined using pulse-wave spectral Doppler at the inflow and outflow cannulae, and the S/D ratio for each was determined. Statistical analysis was performed with SAS, version 9.4 (SAS Institute, Cary, NC), using 2-tailed tests and alpha = 0.05. Thirteen patients were included in the study. Significant differences were observed in S/D ratios among the 3 phases at both the inflow (p = 0.0234) and outflow (p = 0.0047) cannulae. Pairwise tests of the inflow cannulae showed that the mean S/D ratio at the time of thrombosis (mean ± standard deviation [SD], 4.29 ± 1.74) was significantly greater than the prethrombosis ratio (2.49 ± 0.65; p = 0.0069). Among outflow measurements, the mean S/D ratio at thrombosis (3.94 ± 1.34) was significantly higher than both the prethrombosis (2.63 ± 0.56; p = 0.0025) and postthrombosis (2.74 ± 0.83) (p = 0.0093) ratios. Decreases in diastolic velocities were not statistically significant at the inflow cannula. At the outflow cannula, there was a significant difference in diastolic velocity among the phases (p = 0.0233). Specifically, the postthrombosis diastolic measurements (41.50 ± 9.94) were significantly higher than both the prethrombosis (26.85 ± 10.13; p = 0.0140) and thrombosis (26.7 ± 15.35; p = 0.0151) values. CONCLUSIONS: An increased S/D ratio measured with Doppler at the LVAD inflow and outflow cannulas may be associated with pump thrombosis. Decreased diastolic cannula velocities were not observed in LVAD thrombosis.