Association between pulmonary artery pulsatility and mortality after implantation of left ventricular assist device.

AIMS: Right ventricular failure after left ventricular assist device (LVAD) implantation is a major concern that remains challenging to predict. We sought to investigate the relationship between preoperative pulmonary artery pulsatility index (PAPi) and mortality after LVAD implantation. METHODS AND RESULTS: A retrospective analysis of the ASSIST-ICD multicentre registry allowed the assessment of PAPi before LVAD according to the formula [(systolic pulmonary artery pressure - diastolic pulmonary artery pressure)/central venous pressure]. The primary endpoint was survival at 3 months, according to the threshold value of PAPi determined by the receiver operating characteristic (ROC) curve. A multivariate analysis including demographic, echographic, haemodynamic, and biological variables was performed to identify predictive factors for 2 year mortality. One hundred seventeen patients were included from 2007 to 2021. The mean age was 58.45 years (±13.16), with 15.4% of women (sex ratio 5.5). A total of 53.4% were implanted as bridge to transplant and 43.1% as destination therapy. Post-operative right ventricular failure was observed in 57 patients (48.7%), with no significant difference between survivors and non-survivors at 1 month (odds ratio 1.59, P = 0.30). The median PAPi for the whole study population was 2.83 [interquartile range 1.63-4.69]. The threshold value of PAPi determined by the ROC curve was 2.84. Patients with PAPi ≥ 2.84 had a higher survival rate at 3 months [PAPi < 2.84: 58.1% [46.3-72.8%] vs. PAPi ≥ 2.84: 89.1% [81.1-97.7%], hazard ratio (HR) 0.08 [0.02-0.28], P < 0.01], with no significant difference after 3 months (HR 0.67 [0.17-2.67], P = 0.57). Other predictors of 2 year mortality were systemic hypertension (HR 4.22 [1.49-11.97], P < 0.01) and diabetes mellitus (HR 4.90 [1.83-13.14], P < 0.01). LVAD implantation as bridge to transplant (HR 0.18 [0.04-0.74], P = 0.02) and heart transplantation (HR 0.02 [0.00-0.18], P < 0.01) were associated with a higher survival rate at 2 years. CONCLUSIONS: Preoperative PAPi < 2.84 was associated with a higher risk of early mortality after LVAD implantation without impacting 2 year outcomes among survivors.

Doppler echocardiography for surveillance of acute cardiac allograft rejection: a 28-year single-center experience.

Background: Endomyocardial biopsies (EMB) are recommended for the detection of acute cardiac rejection (ACR) despite limited sensitivity. We report the long-term post-transplant results of Doppler echocardiography as a noninvasive alternative of routine EMB. Methods: Two cohorts of heart transplantation (HT) recipients were chronologically defined as follows: the Dual Monitoring Cohort (DMC) from January 1990 to December 1997 included patients who underwent routine EMB and Doppler echocardiography within 24 hours for ACR surveillance; and the "Echo-First Cohort" (EFC), including patients transplanted from January 1998 to December 2018 with Doppler echocardiography as first-line approach for ACR surveillance. Echocardiographic measurements of interest were collected: early diastolic (E) wave peak velocity; pressure half time (PHT) and isovolumetric relaxation time (IVRT). Post-transplant outcomes were reviewed and the Kaplan-Meier approach was used for survival estimates. Inter-operator variability for ultrasound measurements was investigated. Data were collected from medical records from January 2019 to December 2020. Results: A total of 228 patients were included, 99 patients in the DMC and 129 in the EFC. Overall, 5-, 10- and 15-year survival rates were 65.4%, 55.5% and 44.1% respectively, without any significant difference between the two cohorts (log rank test, P=0.71). Echocardiography variables and EMB findings were associated with a mean area under the receiver operating characteristic curve (AUC-ROC) of 0.73 [95% confidence interval (CI): 0.54-0.91], 0.74 (95% CI: 0.54-0.94) and 0.75 (95% CI: 0.57-0.94) respectively for E wave, PHT and IVRT. IVRT and PHT were significantly decreased, and E wave significantly increased, in case of histologically proven ACR. Inter-operator variability was not significant for E wave and IVRT measurements (P=0.13 and 0.30 respectively). Conclusions: Doppler echocardiography as a first-line method for surveillance of ACR did not impair long-term results after HT. These findings suggest that this non-invasive approach might be a reasonable alternative to systematic EMB, limiting risk and improving the quality of life.

Metabolomic profiling of cardiac allografts after controlled circulatory death.

BACKGROUND: Assessment of myocardial viability during ex situ heart perfusion (ESHP) is based on the measurement of lactate concentrations. As this provides with limited information, we sought to investigate the metabolic signature associated with donation after circulatory death (DCD) and the impact of ESHP on the myocardial metabolome. METHODS: Porcine hearts were retrieved either after warm ischemia (DCD group, N = 6); after brain-stem death (BSD group, N = 6); or without DCD nor BSD (Control group, N = 6). Hearts were perfused using normothermic oxygenated blood for 240 minutes. Plasma and myocardial samples were collected respectively every 30 and 60 minutes, and analyzed by an untargeted metabolomic approach using liquid chromatography coupled to high-resolution mass spectrometry. RESULTS: Median duration of warm ischemia was 23 minutes [19-29] in DCD animals. Lactate level within myocardial biopsies was not significantly different between groups at T0 (p = 0.281), and remained stable over the 4-hour period of ESHP. More than 300 metabolites were detected in plasma and heart biopsy samples. Compared to BSD animals, metabolomics changes involving energy and nucleotide metabolisms were observed in plasma samples of DCD animals before initiation of ESHP, whereas 2 metabolites (inosine monophosphate and methylbutyrate) exhibited concentration changes in biopsy samples. Normalization of DCD metabolic profile was remarkable after 4 hours of ESHP. CONCLUSION: A specific metabolic profile was observed in DCD hearts, mainly characterized by an increased nucleotide catabolism. DCD and BSD metabolomes proved normalized during ESHP. Complementary investigations are needed to correlate these findings to cardiac performances.

Ex vivo perfusion of the donor heart: Preliminary experience in high-risk transplantations.

BACKGROUND: The number of heart transplantations (HTs) has decreased in France since 2017 (-5%/year) despite a stable rate of patients referred on the waiting list. Ex vivo heart perfusion (EVHP) is an innovative approach for organ preservation, reducing graft ischaemic time and facilitating continuous organ monitoring before transplantation. AIM: To report our preliminary experience of seven donor hearts preserved with EVHP, including the first heart resuscitated after circulatory-determined death in France. METHODS: Seven hearts were procured from donation after brain death (DBD) for HT or donation after circulatory-determined death (DCD) for research purposes (Protocol PFS20-004, Agence de la Biomédecine, La Plaine Saint-Denis, France). All grafts were preserved using the Organ Care System® (TransMedics Inc., Andover, MA, USA) for normothermic EVHP. Perfusion parameters were adjusted to achieve stable or decreasing arterial lactate trend consistent with suitability for organ transplantation. RESULTS: Indications for EVHP were assessment of a marginal graft in four cases, prolonged preservation in two cases (anticipated duration for retrieval of recipient's heart>3hours) and resuscitation after circulatory-determined death in one case. Median duration of EVHP was 270 (interquartile range 216-343) minutes. five were transplanted, with a median ex situ preservation time (ischaemic time+EVHP time) of 334 (interquartile range 326-444) minutes. The two other grafts were discarded for HT. Three recipients had extracorporeal life support after HT, and presented complete cardiac recovery within a week after HT. One patient died at day 11 because of septic shock. The 3-month survival rate was 75% among recipients. Three months after HT, the left ventricular ejection fraction was>60% in all cases. CONCLUSIONS: EVHP enabled safe prolonged preservation and assessment of marginal grafts. This approach provides an opportunity to expand the donor pool by resuscitating grafts from donors with extended criteria, including controlled DCD.

Urgent desensitization in patients bridged to heart transplantation under extracorporeal membrane oxygenation support: A preliminary experience.

Antihuman leukocyte antigen (HLA) antibodies restrict the access to cardiac allografts. Desensitization therapy is a major challenge in patients with cardiogenic shock waiting for urgent heart transplantation (HT). We retrospectively reviewed six patients (mean age of 37.5 years [16-70]) who underwent plasmapheresis (PP) under extracorporeal membrane oxygenation (ECMO) before transplant between January 2017 and September 2018. The average duration of follow-up was 25 months [20-32]. Mean fluorescence intensity (MFI) of HLA-specific antibodies was reported as follows: score 4 for MFI < 1000, score 6 for 1000 < MFI < 3000 and score 8 for MFI > 3000. The mean duration of ECMO support was 29 days [1-74] and 6.8 [1-29] PP sessions were performed per patient before transplant. The mean number of HLA-specific antibodies before HT was 9.6 for score 6 [4-13] and 5.8 for score 8 [1-12]. Four patients had major complications after transplantation (2 hemorrhagic shocks, 5 infectious events). Mean MFI reduction rate was 94% [79-100] for Class I and 44.2% for Class II [0-83]. Hospital survival was 100%, and early antibody-mediated rejection was diagnosed in one patient at 7 days after HT. Plasmapheresis under ECMO support was associated with favorable early outcomes in highly sensitized candidates for urgent heart transplantation.

Specific Considerations for Venovenous Extracorporeal Membrane Oxygenation During Coronavirus Disease 2019 Pandemic.

Extracorporeal membrane oxygenation (ECMO) is recognized as organ support for potentially reversible acute respiratory distress syndrome (ARDS). However, limited resource during the outbreak and the coagulopathy associated with coronavirus disease 2019 (COVID-19) make the utilization of venovenous (VV) ECMO highly challenging. We herein report specific considerations for cannulation configurations and ECMO management during the pandemic. High blood flow and anticoagulation at higher levels than usual practice for VV ECMO may be required because of thrombotic hematologic profile of COVID-19. Among our first 24 cases (48.8 ± 8.9 years), 17 patients were weaned from ECMO after a mean duration of 19.0 ± 10.1 days and 16 of them have been discharged from ICU.

Anomalous aortic origin of coronary arteries: an alternative to the unroofing strategy.

OBJECTIVES: Anomalous aortic origin of a coronary artery (AAOCA) is the second leading cause of sudden death in children and young adults. The most threatening anatomy is an interarterial and an intramural course, both probably involved in ischaemic phenomena and sudden death. The treatment of interarterial AAOCA remains controversial. Most of the published studies describe the results of the unroofing technique. Our study aims to evaluate the results of a different surgical approach. METHODS: From 2005 to 2019, 61 patients were operated on for an interarterial AAOCA (median age 14.7 years). Forty patients had a right AAOCA, and 21 patients had a left AAOCA including 5 patients with intraseptal course. Seventy percent of patients were symptomatic. Five patients had an aborted sudden cardiac death. Two surgical techniques were used: an 'anatomical' repair for 35 patients (15 left and 22 right AAOCA) or a coronary translocation with creation of a neo-ostia in 19 patients (1 left and 18 right AAOCA). The 5 left AAOCA patients with an intra-septal course required a complete release of the coronary artery from the septum. RESULTS: There was no early or late postoperative death. Three patients had an acute postoperative ischaemic event. Two patients required immediate angioplasty and stenting: 1 patient (7 years) with a hypoplastic right AAOCA and 1 patient (66 years) for inadequate tailoring after septal release. The third patient required an immediate surgical revision (H-2) for left AAOCA thrombosis at the level of the pericardial patch with full myocardial recovery at discharge. During follow-up, 1 patient with right AAOCA translocation and chronic chest pain required subsequent stenting and finally a coronary artery bypass grafting 2 years after initial surgery. One patient who had an asymptomatic mild right coronary stenosis 1 year after anatomical repair was successfully treated by angioplasty alone. All patients but 1 who underwent coronary translocation are totally asymptomatic. All patients with anatomical repair or septal release are free from ischaemic symptoms. CONCLUSIONS: Anatomical repair might provide a better protective option for these patients. Unlike unroofing, it treats the entire intramural segment, relocates the ostium at the appropriate sinus level and corrects any acute take-off angle.