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.).

Unconventional use of total artificial heart in a patient with severe, destructive prosthetic valve endocarditis.

Here, we report the case of a patient who presented to our institution with severe, destructive, and unreconstructable prosthetic valve endocarditis which required the planned implantation of a total artificial heart (TAH) to function as a bridge to cardiac transplantation. The use of TAH in this fashion has been infrequently reported in the literature. This case highlights the importance of a thoughtful, preoperative multidisciplinary approach to these complex patients to provide the most appropriate and life-saving care.

MicroRNA-21 regulates right ventricular remodeling secondary to pulmonary arterial pressure overload.

Right ventricular (RV) function is a critical determinant of survival in patients with pulmonary arterial hypertension (PAH). While miR-21 is known to associate with vascular remodeling in small animal models of PAH, its role in RV remodeling in large animal models has not been characterized. Herein, we investigated the role of miR-21 in RV dysfunction using a sheep model of PAH secondary to pulmonary arterial constriction (PAC). RV structural and functional remodeling were examined using ultrasound imaging. Our results showed that post PAC, RV strain significantly decreased at the basal region compared with t the control. Moreover, such dysfunction was accompanied by increases in miR-21 levels. To determine the role of miR-21 in RV remodeling secondary to PAC, we investigated the molecular alteration secondary to phenylephrine induced hypertrophy and miR21 overexpression in vitro using neonatal rat ventricular myocytes (NRVMs). We found that overexpression of miR-21 in the setting of hypertrophic stimulation augmented only the expression of proteins critical for mitosis but not cytokinesis. Strikingly, this molecular alteration was associated with an eccentric cellular hypertrophic phenotype similar to what we observed in vivo PAC animal model in sheep. Importantly, this hypertrophic change was diminished upon suppressing miR-21 in NRVMs. Collectively, our in vitro and in vivo data demonstrate that miR-21 is a critical contributor in the development of RV dysfunction and could represent a novel therapeutic target for PAH associated RV dysfunction.

Survival after orthotopic heart transplantation in patients with BMI > = 35 with and without diabetes.

BACKGROUND: Orthotopic heart transplant (OHT) recipients with a body mass index (BMI) > = 35 have worse survival than those with a BMI < 35. Diabetes is a risk factor for mortality. We evaluated the impact of diabetes on mortality rates after OHT in patients with a BMI > 35. METHODS: Patients > 18 years who underwent OHT 2008-2017 with a BMI > = 35 were identified in the United Network for Organ Sharing (UNOS) database. Recipient and donor characteristics were compared. A Kaplan Meier analysis was performed. A multivariable Cox proportional hazards model examined the relationship between diabetes and survival. The equivalence of survival outcomes was examined by an unadjusted Cox proportional hazards model and the two one-sided test procedure, using a pre-specified equivalence region. RESULTS: Patients with diabetes were older, had a higher creatinine, lower bilirubin, fewer months on the waitlist, and the donor was less likely to be on inotropes. Kaplan-Meier analysis showed no difference in patient survival. Recipient factors associated with an increased risk of death were increasing bilirubin and machine ventilation. Increasing ischemic time resulted in an increased hazard of death. Long-term survival outcomes were equivalent. CONCLUSIONS: In OHT recipients with a BMI > 35, there is no statistical difference in longterm survival in recipients with or without diabetes. These results encourage continued consideration for OHT in patients BMI > 35 with coexisting diabetes.

The changing landscape of percutaneous technology leading to surgical complications.

With new technology comes new complications. We discuss the interesting case presented by Bjelic and colleagues regarding a misplaced TAVR (transcatheter aortic valve replacement) valve into the inflow cannula of a left ventricular assist device, leading to hemodynamic collapse. The author describes the pitfalls of the new technology and interesting surgical maneuvers to address these complications.

Left ventricular assist device implantation by bi-thoracotomy technique: A single-center perspective.

BACKGROUND: Left ventricular assist devices (LVAD) are standardly implanted via full sternotomy. Nonsternotomy approaches are gaining popularity, but potential benefits of this approach have not been well-studied. We hypothesized that LVAD implantation by bi-thoracotomy (BT) would demonstrate smaller and more consistent inflow cannula angles leading to improved postoperative outcomes compared to sternotomy. METHODS: Charts of patients who underwent LVAD implantation between June 2018 and June 2020 at a single academic institution were retrospectively reviewed. Patient demographics, surgical approach (sternotomy vs. BT), laboratory values, and postoperative course were compared. The inflow cannula angle was measured on the first chest radiograph available postoperatively. RESULTS: Of 40 patients studied, BT approach was used in 17 (42.5%). Mean inflow cannula angles were smaller in BT patients (23.0 vs. 37.1 degrees, p = .018) and had a smaller standard deviation (13.8 vs. 20.3). Excluding patients who went on to receive a heart transplant or died in the same hospitalization, there was no difference in median length of hospital stay after surgery (16.0 vs. 17.5 days, p = .768). However, BT patients required fewer days of postoperative inotrope support (4.0 vs. 7.0 days, p = .012). CONCLUSIONS: Our data suggest inflow cannula angles are smaller and more consistent with the BT approach, which leads to a shorter duration of postoperative inotropic support. This finding may suggest improved right heart function following LVAD implant via BT approach. Further study is warranted to determine additional benefits of the BT approach.

Successful heart transplantation in a patient who recovered from COVID-19.

Coronavirus disease-2019 has created unprecedented challenges for society, and specifically the medical community. While the pandemic continues to unfold, the transplant community has had to pivot to keep recipients, donors, and institutional transplant teams safe given the unique circumstances inherent to solid organ transplantation.

Balancing supply and demand: Review of the 2018 donor heart allocation policy.

Heart transplant remains the most effective treatment for patients with end stage heart failure. Advances in mechanical circulatory support devices have changed the therapeutic landscape and contributed to a demographic shift in patients awaiting transplant. In the setting of a growing waitlist and concern for an inability of current policies to accurately account for patient acuity and equitable geographic distribution of organs, the United Network for Organ Sharing developed a new donor heart allocation policy which was introduced in 2018. The new policy creates more precise listing criteria to reflect patient acuity, addresses previously marginalized groups, and takes steps to address geographic inequalities.

Long-term discontinuation of warfarin in a patient with HeartMate 3 left ventricular assist device without complication.

A 38-year-old woman with peripartum cardiomyopathy underwent placement of a HeartMate 3 (HM3) left ventricular assist device (LVAD). Postoperatively, she refused warfarin therapy and was maintained on aspirin monotherapy for 19 months. She did not experience thrombotic or thromboembolic complications associated with lack of oral vitamin K antagonist anticoagulation. Our patient represents the longest reported duration of a patient with HM3 LVAD maintained without warfarin without evidence of thrombotic or thromboembolic events.

The effect of donor age on posttransplant mortality in a cohort of adult cardiac transplant recipients aged 18-45.

Hearts from older donors are increasingly utilized for transplantation due to unmet demand. Conflicting evidence exists regarding the prognosis of recipients of advanced age donor hearts, especially in young recipients. A retrospective analysis was performed on 11 433 patients aged 18 to 45 who received a cardiac transplant from 2000 to 2017. Overall, 10 279 patients received hearts from donors less than 45 and 1145 from donors greater than 45. Recipients of older donors were older (37 vs. 34 years, P < .01) and had higher rates of inotropic dependence (48% vs. 42%, P < .01). However, groups were similar in terms of comorbidities and dependence on mechanical circulatory support. Median survival for recipients of older donors was reduced by 2.6 years (12.6 vs. 15.2, P < .01). Multivariable analysis demonstrated donor age greater than 45 to be a predictor of mortality (HR 1.18 [1.05-1.33], P = .01). However, when restricting the analysis to patients who received a donor with a negative preprocurement angiogram, donor age only had a borderline association with mortality (HR 1.20 [0.98-1.46], P = .06). Older donor hearts in young recipients are associated with decreased long-term survival, however this risk is reduced in donors without atherosclerosis. The long-term hazard of this practice should be carefully weighed against the risk of waitlist mortality.

Echocardiographic Assessment of Biventricular Function in 249 Patients During the Peri-Extracorporeal Membrane Oxygenation Period.

OBJECTIVES: At a quaternary care center that regularly performs and cares for patients undergoing extracorporeal membrane oxygenation (ECMO), a database of all adult patients since 2009 was assembled with echocardiographic parameters of left (LV) and right (RV) ventricular function. From the database, 175 venoarterial (VA) and 74 venovenous (VV) ECMO patients were analyzed to compare the decannulation echocardiographic assessments of biventricular function before, during, and after ECMO in survivors and nonsurvivors. DESIGN: Retrospective chart review-based study. SETTING: A single quaternary care center. PARTICIPANTS: All adult patients who received ECMO from 2009 to 2017 with both survival data and echographic studies were included in this retrospective study. INTERVENTIONS: When indicated, transthoracic and transesophageal echocardiograms were performed for ECMO patients. The results of these echocardiograms were reviewed retrospectively, and differences between survivors and nonsurvivors were examined. MEASUREMENTS AND MAIN RESULTS: A retrospective chart review of before, during cannulation, and after decannulation echocardiographic assessments of biventricular function was performed. On average, VA ECMO survivors had better post-decannulation LV function than did nonsurvivors by a full clinical grade-mild impairment versus moderate impairment (p < 0.001). RV function comparison was similar-mild impairment in survivors versus moderate impairment in nonsurvivors (p = 0.007). LV and RV function before and during ECMO in survivors was not different from that of nonsurvivors. The change in biventricular function from before to after cannulation and during cannulation to post-cannulation was approximately a full clinical grade better in survivors than nonsurvivors (p < 0.01 in all cases). In VV ECMO patients, post-decannulation RV function was significantly worse in nonsurvivors (moderate dysfunction vs borderline normal function) (p = 0.013). CONCLUSIONS: Retrospective chart review of 249 patients suggests that echocardiographic assessment of biventricular function before ECMO cannulation is not prognostic in VA or VV ECMO patients. Post-decannulation assessment of biventricular function may aid in triaging more "at risk" patients because nonsurvivors have significantly worse biventricular function after decannulation. The failure to improve biventricular function from the before to after ECMO phases and the during to after ECMO phases is concerning for a poor prognosis.

Papillary muscle rupture following routine aortic valve replacement.

A 56-year-old man who underwent routine aortic valve replacement (AVR) for aortic insufficiency suffered a presumed embolic event to a small vessel supplying the posteromedial papillary muscle. This led to papillary muscle rupture, and severe, acute mitral regurgitation requiring emergent mitral valve replacement 6 days postoperatively. Small-vessel coronary embolization outside the setting of infection/endocarditis leading to infarction and papillary muscle rupture following elective AVR has not been previously described in the literature.

Helpful sternal wound vacuum-assisted closure techniques in two open chest situations: Central extracorporeal membrane oxygenation and sternal infection.

BACKGROUND: Dressing open sternal wounds after cardiac surgery can be challenging. In cases where extracorporeal membrane oxygenation (ECMO) is required, the sternum is left open with cannulae traversing the wound, making it difficult to create a water-tight seal and maintain sterility. Patients with a deep sternal infection may also be left with an open sternum between the time of debridement and reconstruction; in such cases, stabilizing the dressing in an ambulatory patient can pose a challenge. METHODS: Two cases are reviewed, each highlighting the solutions to the problems mentioned above. RESULTS: In case 1, a patient with an open sternum and central ECMO, we describe construction of a dressing that achieves air seal and blood seal, and helps maintain the cannulae in a safe, stable position. In case 2, an ambulatory patient, we describe a modification of a recently published "Two Bridge Technique" that provides a stable dressing in three dimensions. CONCLUSION: Performance of specific techniques and attention to detail in complex situations can make a big difference in open sternum patients treated with temporary, vacuum-assisted dressings. Achieving vacuum and fluid seal is important for sterility, integrity of adjacent skin, and caregiver safety.

Pain management and safety profiles after preoperative vs postoperative thoracic epidural insertion for bilateral lung transplantation.

OBJECTIVE: Thoracic epidural analgesia provides effective pain control after lung transplantation; however, the optimal timing of placement is controversial. We sought to compare pain control and pulmonary and epidural morbidity between patients receiving preoperative vs postoperative epidurals. METHODS: Institutional records were reviewed for patients undergoing a bilateral lung transplant via a bilateral anterior thoracotomy with transverse sternotomy incision between January 2014 and January 2017. Pain control was measured using visual analog scale pain scores (0-10). Pulmonary complications included a composite of pneumonia, prolonged intubation, and reintubation/tracheostomy. RESULTS: Among 103 patients, 72 (70%) had an epidural placed preoperatively and 31 (30%) had an epidural placed within 72 hours posttransplant. There were no differences in the rates of cardiopulmonary bypass (3% vs 0%, P = 0.59); however, patients with a preoperative epidural were less likely to be placed on extracorporeal membrane oxygenation intraoperatively (25% vs 52%, P = 0.01). Pain control was similar at 24 hours (1.2 vs 1.7, P = 0.05); however, patients with a preoperative epidural reported lower pain scores at 48 (1.2 vs 2.1, P = 0.02) and 72 hours posttransplant (0.8 vs 1.7, P = 0.02). There were no differences in primary graft dysfunction (42% vs 56%, P = 0.28), length of mechanical ventilation (19.5 vs 24 hours, P = 0.18), or adverse pulmonary events (33% vs 52%, P = 0.12). No adverse events including epidural hematoma, paralysis, or infection resulted from epidural placement. CONCLUSION: Preoperative thoracic epidural placement provides improved analgesia without increased morbidity following lung transplantation.

Impella Placement Guided by Echocardiography Can Be Used as a Strategy to Unload the Left Ventricle During Peripheral Venoarterial Extracorporeal Membrane Oxygenation.

OBJECTIVE: At the authors' institution, before 2015, patients cannulated for peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO) did not undergo left ventricular (LV) decompression with the use of an LV vent. After 2015, the authors' institution began using the Impella device to vent the left ventricle in patients on VA-ECMO. The authors hypothesized that survival outcomes would improve in patients on VA-ECMO with the use of an Impella for LV venting. DESIGN: Retrospective, chart based review study. SETTING: Single center, university-based hospital. PARTICIPANTS: All adult patients at the authors' institution who required VA-ECMO between January 2015 and May 2017. INTERVENTION: An Impella (Abiomed, Danvers, MA) device was placed percutaneously in patients cannulated for VA-ECMO as a mechanism to provide LV venting and decompression, therefore unloading the heart. MEASUREMENTS AND MAIN RESULTS: Manual chart review was conducted, and a survival analysis was performed. It was observed that patients on VA-ECMO in whom an Impella was implanted had improved survival and an improvement in LV function as demonstrated by echocardiography compared with patients maintained on VA-ECMO alone. CONCLUSIONS: Patients on VA-ECMO plus Impella implantation demonstrated improved survival compared with patients treated with VA-ECMO alone. Key echocardiographic characteristics such as improved LV function after Impella placement and LV cavity size reduction during therapy may help predict those patients who may benefit most from this cannulation strategy.

Delayed Presentation of Traumatic Pericardial Rupture: Diagnostic and Surgical Considerations for Treatment.

Traumatic pericardial rupture is a rare event with high mortality. We present the case of a 15-year-old boy who sustained thoracic and abdominal trauma secondary to motor vehicle collision, with a delayed diagnosis of traumatic pericardial rupture with cardiac herniation. Out of concern for torsion and hemodynamic collapse, surgical repair was advised. We have developed a novel surgical approach to this rare condition, utilizing a combination of thoracoscopic and open surgical techniques. The guiding principles of our repair include the utilization of fenestrated pieces of bovine pericardium to create a tension free repair, minimizing the likelihood of pericardial effusion, and returning the cardiac mass to normal anatomic position.

Post-Myocardial Infarction Ventricular Septal Defect Six Months following Coronary Artery Bypass Grafting.

Mechanical complications following acute myocardial infarction are associated with high mortality. We present the first reported case of a new post myocardial infarction ventricular septal defect (VSD) within six months of coronary artery bypass grafting. The patient underwent successful surgical correction of the VSD with the assistance of mechanical circulatory support (MCS). This case highlights the importance of mechanical circulatory support in the management of cardiogenic shock associated with rare complications of myocardial infarction, even after surgical revascularization.

Increasing Utilization of Extended Criteria Donor Hearts for Transplantation: The OCS Heart EXPAND Trial.

BACKGROUND: Extended criteria donor (ECD) hearts available with donation after brain death (DBD) are underutilized for transplantation due to limitations of cold storage. OBJECTIVES: This study evaluated use of an extracorporeal perfusion system on donor heart utilization and post-transplant outcomes in ECD DBD hearts. METHODS: In this prospective, single-arm, multicenter study, adult heart transplant recipients received ECD hearts using an extracorporeal perfusion system if hearts met study criteria. The primary outcome was a composite of 30-day survival and absence of severe primary graft dysfunction (PGD). Secondary outcomes were donor heart utilization rate, 30-day survival, and incidence of severe PGD. The safety outcome was the mean number of heart graft-related serious adverse events within 30 days. Additional outcomes included survival through 2 years benchmarked to concurrent nonrandomized control subjects. RESULTS: A total of 173 ECD DBD hearts were perfused; 150 (87%) were successfully transplanted; 23 (13%) did not meet study transplantation criteria. At 30 days, 92% of patients had survived and had no severe PGD. The 30-day survival was 97%, and the incidence of severe PGD was 6.7%. The mean number of heart graft-related serious adverse events within 30 days was 0.17 (95% CI: 0.11-0.23). Patient survival was 93%, 89%, and 86% at 6, 12, and 24 months, respectively, and was comparable with concurrent nonrandomized control subjects. CONCLUSIONS: Use of an extracorporeal perfusion system resulted in successfully transplanting 87% of donor hearts with excellent patient survival to 2 years post-transplant and low rates of severe PGD. The ability to safely use ECD DBD hearts could substantially increase the number of heart transplants and expand access to patients in need. (International EXPAND Heart Pivotal Trial [EXPANDHeart]; NCT02323321; Heart EXPAND Continued Access Protocol; NCT03835754).