Results of large pulmonary homograft implantation for right ventricular outflow tract reconstruction.

BACKGROUND: To evaluate the long-term results of implantation of homogeneous large size of pulmonary homograft (PH) for reconstruction of the right ventricular outflow tract (RVOT). METHODS: Between January 2000 and December 2017, 107 patients were implanted with PH for reconstruction of the RVOT. Data were collected retrospectively in this single-center study. PH failure was defined as a peak of gradient greater than 40 mmHg and/or as a pulmonary regurgitation greater than Grade 2. Primary endpoint was the reoperation of the RVOT during follow-up. Secondary endpoints were overall survival, occurrence of PH failure and the rate of reoperation for all cause. RESULTS: Mean age of the recipients was 26.1 ± 13.6 years. Median follow-up interval was 2.99 years (interquartile range [IQR]: 6.2). Mean size of PH was 24.9 ± 1.9 mm. Reoperation of the RVOT occurred in eight patients (7.8%). Time before reoperation was 2.74 years (IQR: 6.4). Freedom from reoperation for RVOT at 5 and 10 years was respectively 95.7% and 90.0%. Overall survival at 10 years was 95.2%. PH failure occurred in 13 patients (12.0%). Median time before PH failure was 6.7 years (IQR: 9.6). Freedom from PH failure at 10 years was 81.6%. Reoperation for PH failure occurred in four patients (3.9%). Concomitant tricuspid surgery (p = .01; 95% confidence interval [CI]: 1.9-319.6) and undersized PH (p = .01; 95% CI: 2.06-719.8) were independent risk factors of late reoperation. CONCLUSION: Implantation of large PH for RVOT reconstruction provides excellent midterm results in terms of reoperation.

Effects of high-intensity inspiratory muscle training on systemic inflammatory response in cardiac surgery - A randomized clinical trial.

PURPOSE: Preoperative inspiratory muscle training reduces the incidence of postoperative pulmonary complications after cardiac surgery, but training protocols vary widely in terms of intensity. Currently, the mechanisms underlying the effectiveness of this practice are not known. The purpose of the present study is to determine whether preoperative high-intensity inspiratory muscle training (HI-IMT) modulates the perioperative systemic inflammatory response in cardiac surgery patients. METHODS: Participants awaiting surgical aortic valve replacement were randomized to 3 to 6 weeks preoperative home-based HI-IMT or same duration low-intensity inspiratory muscle training (LI-IMT). The primary outcome was the preoperative value of the soluble tumor necrosis factor receptor 1 (sTNFR1). Secondary outcomes assessed perioperative evolution of the cytokines: sTNFR1, Tumor necrosis factor-α, Interleukin (IL)-6, IL-8, IL10, IL1ß, and their combined z-score; reflecting post-training and postoperative inflammatory response. Perioperative pulmonary function and postoperative clinical outcomes were collected. RESULTS: Between February 2018 and March 30, 2019 patients were randomized, to HI-IMT or LI-IMT. There were no differences between the groups in terms of baseline characteristics. The median (IQR) training duration was 34 (28-44) days. After training, the median (IQR) predicted maximal inspiratory pressure was higher in the HI-IMT vs LI-IMT group (119 (96-142%) vs 97 (81-107%); p = .04) Levels of the sTNFR1 cytokine increased during training in the HI-IMT group, pre vs post training (Median (IQR) 1073 (920; 1219) vs 1172 (965; 1368) ng/L; p = .03). The 24-h postoperative global inflammatory score was lower in the HI-IMT than in the LI-IMT group (Median (IQR), -0.37 (-0.62, 0.03) vs -0.10 (-0.17, 0.49), p = .04). Global inflammatory scores were not different at other time points. There were no significant differences between the groups in post-operative pulmonary function and postoperative clinical outcome. CONCLUSION: High intensity inspiratory muscle training shows immunomodulatory properties. These properties could explain why preoperative inspiratory muscle training can lead to lung protection after cardiac surgery.

A Case Report of Pulmonary Embolectomy Under Cardiopulmonary Bypass in a Patient with Intracranial Hemorrhage and History of Heparin-Induced Thrombocytopenia.

Pulmonary embolism is a common complication after intracranial hemorrhage. As thrombolysis is contraindicated in this situation, surgical pulmonary embolectomy may be indicated in case of high-risk pulmonary embolism but requires transient anticoagulation with heparin during cardiopulmonary bypass. We report the case of a patient with a history of heparin-induced thrombocytopenia who presented with a high-risk pulmonary embolism 10 days after the spontaneous onset of a voluminous intracerebral hematoma. Despite high doses of heparin required to run the cardiopulmonary bypass and subsequent anticoagulation by danaparoid sodium, the brain hematoma remained stable and the patient was discharged without complications 30 days after surgery.

En bloc video-assisted thoracoscopic vertebrectomy for a spinal tumour.

Complex thoracic vertebral tumours remain a surgical challenge in terms of the surgical approach to ensure a complete en bloc vertebrectomy with healthy margins, along with optimal control of the thoracic structures next to the spine. A combined three-port left thoracoscopic posterior approach, with the patient placed in a prone position with selective double-lumen intubation, can be performed in patients with spinal tumours involving soft tissues, for direct access to the thoracic structures, even with T10-T11 vertebral tumours next to the diaphragm. The video thoracoscopic technique with an enhanced view of the posterior mediastinum permits progressive dissection of the descending aorta, oesophagus, azygos vein, thoracic ductus and diaphragmatic pillars from the vertebral body that is involved by the spinal tumour. The complete dissection of those structures from the spine provides a good surgical view of the contralateral pleural cavity to enable complete control of the tumoral mass. A complete en bloc vertebrectomy with spinal cord ligation is then completely and safely performed with Gigli saws above and under the tumour, respecting healthy tissue margins, under video thoracoscopic monitoring of the anterior structures. Finally, a spinal prosthesis is positioned through the posterior access and stabilized with thoracic and lumbar spinal arthrodesis.

Pulmonary hypertension without heart failure causes cardiorenal syndrome in a porcine model.

Cardiorenal syndromes type 1 and 2 are complex disorders in which cardiac dysfunction leads to kidney dysfunction. However, the mechanisms remain incompletely explained, during pulmonary hypertension in particular. The objective of this study is to develop an original preclinical model of cardiorenal syndrome secondary to a pulmonary hypertension in piglets. Twelve 2-month-old Large White piglets were randomized in two groups: (1) induction of pulmonary hypertension by ligation of the left pulmonary artery and iterative embolizations of the right lower pulmonary artery, or (2) Sham interventions. We evaluated the cardiac function using right heart catheterization, echocardiography and measurement of biochemistry markers). Kidney was characterized using laboratory blood and urine tests, histological evaluation, immunostainings for renal damage and repair, and a longitudinal weekly assessment of the glomerular filtration rate using creatinine-based estimation and intravenous injection of an exogenous tracer on one piglet. At the end of the protocol (6 weeks), the mean pulmonary artery pressure (32 ± 10 vs. 13 ± 2 mmHg; p = 0.001), pulmonary vascular resistance (9.3 ± 4.7 vs. 2.5 ± 0.4 WU; p = 0.004) and central venous pressure were significantly higher in the pulmonary hypertension group while the cardiac index was not different. Piglets with pulmonary hypertension had higher troponin I. We found significant tubular damage and an increase in albuminuria in the pulmonary hypertension group and negative correlation between pulmonary hypertension and renal function. We report here the first porcine model of cardiorenal syndrome secondary to pulmonary hypertension.

Functional Assessment of the Donor Heart During Ex Situ Perfusion: Insights from Pressure-Volume Loops and Surface Echocardiography.

Heart transplantation remains the gold standard treatment for advanced heart failure. However, the current critical organ shortage has resulted in the allocation of a growing number of donor hearts with extended criteria. These marginal grafts are associated with a high risk of primary graft failure and may benefit from ex situ perfusion before transplant. This technology allows for extended organ preservation using warm oxygenated blood perfusion with continuous metabolic monitoring. The only NESP device currently available for clinical practice perfuses the organ in an unloaded non-working state, which does not allow for functional assessment of the beating heart. We therefore developed an original platform of NESP in working mode conditions with adjustment of left ventricular preload and afterload. This protocol was applied in porcine hearts. Ex situ functional assessment of the heart was achieved with intracardiac conductance catheterization and surface echocardiography. Along with a description of the experimental protocol, we herein report the main results, as well as pearls and pitfalls associated with the acquisition of pressure-volume loops and myocardial power during NESP. Correlations between hemodynamic findings and ultrasound variables are of major interest, especially for further rehabilitation of donor hearts before transplantation. This protocol aims to improve the assessment of donor hearts to both increase the donor pool and reduce the incidence of primary graft failure.

Induction and Phenotyping of Acute Right Heart Failure in a Large Animal Model of Chronic Thromboembolic Pulmonary Hypertension.

The development of acute right heart failure (ARHF) in the context of chronic pulmonary hypertension (PH) is associated with poor short-term outcomes. The morphological and functional phenotyping of the right ventricle is of particular importance in the context of hemodynamic compromise in patients with ARHF. Here, we describe a method to induce ARHF in a previously described large animal model of chronic PH, and to phenotype, dynamically, right ventricular function using the gold standard method (i.e., pressure-volume PV loops) and with a non-invasive clinically available method (i.e., echocardiography). Chronic PH is first induced in pigs by left pulmonary artery ligation and right lower lobe embolism with biological glue once a week for 5 weeks. After 16 weeks, ARHF is induced by successive volume loading using saline followed by iterative pulmonary embolism until the ratio of the systolic pulmonary pressure over systemic pressure reaches 0.9 or until the systolic systemic pressure decreases below 90 mmHg. Hemodynamics are restored with dobutamine infusion (from 2.5 µg/kg/min to 7.5 µg/kg/min). PV-loops and echocardiography are performed during each condition. Each condition requires around 40 minutes for induction, hemodynamic stabilization and data acquisition. Out of 9 animals, 2 died immediately after pulmonary embolism and 7 completed the protocol, which illustrates the learning curve of the model. The model induced a 3-fold increase in mean pulmonary artery pressure. The PV-loop analysis showed that ventriculo-arterial coupling was preserved after volume loading, decreased after acute pulmonary embolism and was restored with dobutamine. Echocardiographic acquisitions allowed to quantify right ventricular parameters of morphology and function with good quality. We identified right ventricular ischemic lesions in the model. The model can be used to compare different treatments or to validate non-invasive parameters of right ventricular morphology and function in the context of ARHF.

Aortic homograft for aortic valve replacement in patient with Alpha-Gal allergy.

Allergy to Galactose-Alpha-1,3-Galactose is an allergy to mammalian proteins, that are present on the surface of standard bioprosthestic valves, and could result in a catastrophic allergic reaction or may cause early deterioration of the bioprostheses. Aortic homograft is an acceptable alternative to standard prosthetic valves (biological and mechanical) to avoid a potential allergic manifestation and the need for definitive oral anticoagulation. We report the implantation of an aortic homograft in a patient with an aortic stenosis who presents a documented AlphaGal allergy.

Preservation of the Aortic Root During Type A Aortic Dissection Surgery: An Effective Strategy?

BACKGROUND: Management of the aortic root during acute Type A aortic dissection (TAAD) repair remains controversial in term of long-term evolution and reoperation. The aim of this study was to assess the long-term outcomes of the aortic root after conservative management during primary surgery. METHODS: One hundred sixty-four consecutive patients were included in this monocentric retrospective study. The primary endpoint was reoperation on the aortic root during long-term follow-up. Forty-six patients had aortic root replacement (ARR) and 118 had supracoronary aortic replacement (SCR). The 10-year survival, occurrence of significant aortic regurgitation, and radiologic aortic root dilatation in each group were assessed during follow-up. RESULTS: Patients from ARR group were younger than those from SCR group (p < 0.0001). Median follow-ups of ARR group and SCR group are 4.4 (interquartile range [IR]: 2.6-8.3) and 6.15 (IR: 2.8-10.53) years, respectively. Reoperation of the aortic root during long-term follow-up was similar in both groups (ARR group: 5.1%, SCR group: 3.3%, p = 0.636). The 10-year survivals of ARR and SCR groups were 64.8 ± 12.3% and 46.3 ± 5.8% (p = 0.012), respectively. Long-term significant aortic regurgitation occurred in one patient (1.7%) and seven patients (7.6%) of the ARR and SCR groups (p = 0.176), respectively. Radiologic aortic root diameters in the SCR group were similar between postoperative period and follow-up studies (p = 0.58). Reoperation on the distal aorta (p = 0.012) and patent radiologic false lumen of the descending aorta (p = 0.043) were independent risk factors of late death. CONCLUSION: SCR is an effective technique for primary TAAD surgery and does not increase the rate of late reoperation on the aortic root.

STABILISE Technique via a Transapical Approach to Repair Residual Type A Aortic Dissection.

The stent-assisted balloon-induced intimal disruption and relamination in aortic dissection or STABILISE concept is a novel endovascular strategy in Type A and Type B dissections. We report a case of Type A aortic dissection repair combining, first, an open thoracic aortic surgery with an elephant trunk procedure and, second, an endovascular treatment using the STABILISE technique via a combined transapical approach commonly used for transcatheter aortic valve implantation and a femoral pathway.

Author's reply (in reference to letter to editor proposed by Etem Caliskan, Catherine J. Pachuk, Louis P. Perrault, Maximilian Y Emmert and entitled: preservation solutions to improve graft patency: The devil is in the detail).

Not applicable.

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.

Cardiopulmonary bypass and internal thoracic artery: Can roller or centrifugal pumps change vascular reactivity of the graft? The IPITA study: A randomized controlled clinical trial.

BACKGROUND: Cardiopulmonary bypass (CPB) induces a systemic inflammatory response (SIRS) and affects the organ vascular bed. Experimentally, the lack of pulsatility alters myogenic tone of resistance arteries and increases the parietal inflammatory response. The purpose of this study was to compare the vascular reactivity of the internal thoracic arteries (ITAs) due to the inflammatory response between patients undergoing coronary artery bypass grafting (CABG) under CPB with a roller pump or with a centrifugal pump. METHODS: Eighty elective male patients undergoing CABG were selected using one or two internal thoracic arteries under CPB with a roller pump (RP group) or centrifugal pump (CFP group). ITA samples were collected before starting CPB (Time 1) and before the last coronary anastomosis during aortic cross clamping (Time 2). The primary endpoint was the endothelium-dependent relaxation of ITAs investigated using wire-myography. The secondary endpoint was the parietal inflammatory response of arteries defined by the measurements of superoxide levels, leukocytes and lymphocytes rate and gene expression of inflammatory proteins using. Terminal complement complex activation (SC5b-9) and neutrophil activation (elastase) analysis were performed on arterial blood at the same times. RESULTS: Exposure time of ITAs to the pump flow was respectively 43.3 minutes in the RP group and 45.7 minutes in the CFP group. Acetylcholine-dependent relaxation was conserved in the two groups whatever the time. Gene expression of C3 and C4a in the artery wall decreased from Time 1 to Time 2. No oxidative stress was observed in the graft. There was no difference between the groups concerning the leukocytes and lymphocytes rate. SC5b-9 and elastase increased between Time 1 and Time 2. CONCLUSION: Endothelium-dependent relaxation of the internal thoracic arteries was preserved during CPB whatever the type of pump used. The inflammatory response observed in the blood was not found in the graft wall within this time frame. TRIAL REGISTRATION: Name of trial study protocol: IPITA Registration number (ClinicalTrials.gov): NCT04168853.

Do storage solutions protect endothelial function of arterialized vein graft in an experimental rat model?

BACKGROUND: This study aims to compare the effects of storage solutions commonly used in coronary artery bypass grafting on the vascular reactivity in vein graft interposed in arterial position in syngeneic rats. METHODS: Twenty-seven male Lewis rats were sacrified to sample a vein graft implanted 6 weeks ago into abdominal aorta position. The vein grafts were inferior venae cavae initially pretreated with heparinized saline solution (HS) or autologous heparinized blood (AHB) or our referent solution, GALA. The endothelial functionality, the in situ Reactive Oxygen Species (ROS) levels and the histological characteristics were conducted from segments of arterialized vein graft. RESULTS: At 6 weeks, graft thrombosis occurred respectively in 22% of AHB group, 62.5% in the HS group and 82.5% in the GALA group. In each group, significative intimal hyperplasia was observed. After 6 weeks, an endothelium-remodeling layer associated with an increase of wall thickness was observed in each group. Endothelium-dependent tone was reduced in the vein graft regardless of the group. No difference was observed concerning the ROS in vein graft between the different groups. In distal aortic sections, ROS levels were increased in HS and GALA groups. CONCLUSIONS: Storage solutions used in this experimental model of vein graft implanted in arterial position cause graft injury and a complete disappearance of vascular reactivity. GALA solution did not reduce intimal risk hyperplasia when the vein graft was exposed to arterial flow in a rat model.

Clinical outcomes in patients after extracorporeal membrane oxygenation support for post-cardiotomy cardiogenic shock: a single-centre experience of 92 cases.

OBJECTIVES: Post-cardiotomy cardiogenic shock is a major concern in cardiac surgery. We reviewed our experience of extracorporeal membrane oxygenation (ECMO) as temporary circulatory support in post-cardiotomy cardiogenic shock. METHODS: Between January 2005 and December 2014, adult patients implanted with ECMO after cardiac surgical procedures were included. Indications for ECMO were failure to be withdrawn from cardiopulmonary bypass or refractory cardiogenic shock occurring during postoperative Days 1 and 2. Patients' characteristics and outcomes were prospectively collected in a local ECMO database. RESULTS: Ninety-two patients, median age of 63 years (17-83 years), were supported by ECMO following valvular surgery (66%), acute aortic dissection (10%) and coronary artery bypass grafting (9%). A total of 37% were combined surgical procedures, 24% were redo procedures and 33% were emergent procedures. The median duration of ECMO support was 6 days (1-28 days). The weaning rate from mechanical support was 48%. Overall 1-month and 6-month survival rates were, respectively, 42% and 39%. Survivors were younger (57 vs 63 years old, P = 0.02) and had a higher preoperative left ventricular ejection fraction (52.5 vs 44.1%, P = 0.017). There was a trend for lower serum creatinine levels and total bilirubin rates in the survivors' group 24 h after initiation of ECMO (respectively, 162 vs 212 µmol/l, P = 0.06; 25.3 vs 54.2 mg/dl, P = 0.08). Valvular surgery and peak lactic acid serum level were associated with poor outcomes. The mean health-related quality of life EuroQoL scale was 68 ± 16/100 at 2 years. CONCLUSIONS: Refractory cardiogenic shock requiring ECMO was most frequently observed after redo valvular surgery in the present study. The overall 6-month survival rate was 39% after ECMO support for post-cardiotomy cardiogenic shock with acceptable health-related quality of life. Improved kidney and liver functions after 24 h of support were associated with favourable outcomes.

Cardiogenic shock induced by a voluminous phaeochromocytoma rescued by concomitant extracorporeal life support and open left adrenalectomy.

Phaeochromocytoma is a rare catecholamine-secreting tumour involved in 0.1-0.2% cases of hypertension in the general population. Headache, palpitation and paroxystic sweating are the most commonly described symptoms. A few published cases report an acute adrenergic cardiomyopathy, leading to severe cardiogenic shock requiring mechanical circulatory support. We report the case of a 57-year old patient presenting a voluminous phaeochromocytoma of the left adrenal gland revealed by cardiogenic shock and rescued by peripheral extracorporeal life support device (ECLS). Left surrenalectomy has been performed under protective ECLS during the same surgical procedure. The patient was successfully weaned from ECLS on Day 7 after surgery and myocardial function completely recovered when the patient was discharged from the hospital.