Heart graft preservation technics and limits: an update and perspectives.

Heart transplantation, the gold standard treatment for end-stage heart failure, is limited by heart graft shortage, justifying expansion of the donor pool. Currently, static cold storage (SCS) of hearts from donations after brainstem death remains the standard practice, but it is usually limited to 240 min. Prolonged cold ischemia and ischemia-reperfusion injury (IRI) have been recognized as major causes of post-transplant graft failure. Continuous ex situ perfusion is a new approach for donor organ management to expand the donor pool and/or increase the utilization rate. Continuous ex situ machine perfusion (MP) can satisfy the metabolic needs of the myocardium, minimizing irreversible ischemic cell damage and cell death. Several hypothermic or normothermic MP methods have been developed and studied, particularly in the preclinical setting, but whether MP is superior to SCS remains controversial. Other approaches seem to be interesting for extending the pool of heart graft donors, such as blocking the paths of apoptosis and necrosis, extracellular vesicle therapy, or donor heart-specific gene therapy. In this systematic review, we summarize the mechanisms involved in IRI during heart transplantation and existing targeting therapies. We also critically evaluate all available data on continuous ex situ perfusion devices for adult donor hearts, highlighting its therapeutic potential and current limitations and shortcomings.

Aortic valve repair versus mechanical valve replacement for root aneurysm: the CAVIAAR multicentric study.

OBJECTIVES: Despite growing evidence that aortic valve repair improves long-term patient outcomes and quality of life, aortic valves are mostly replaced. We evaluate the effect of aortic valve repair versus replacement in patients with dystrophic aortic root aneurysm up to 4 years. METHODS: The multicentric CAVIAAR (Conservation Aortique Valvulaire dans les Insuffisances Aortiques et les Anévrismes de la Racine aortique) prospective cohort study enrolled 261 patients: 130 underwent standardized aortic valve repair (REPAIR) consisting of remodelling root repair with expansible aortic ring annuloplasty, and 131 received mechanical composite valve and graft replacement (REPLACE). Primary outcome was a composite criterion of mortality, reoperation, thromboembolic or major bleeding events, endocarditis or operating site infections, pacemaker implantation and heart failure, analysed with propensity score-weighted Cox model analysis. Secondary outcomes included major adverse valve-related events and components of primary outcome. RESULTS: The mean age was 56.1 years, and valve was bicuspid in 115 patients (44.7%). Up to 4 years, REPAIR did not significantly differ from REPLACE in terms of primary outcome [Hazard Ratio (HR) 0.66 (0.39; 1.12)] but showed significantly less valve-related deaths (HR 0.09 [0.02; 0.34]) and major bleeding events (HR 0.37 [0.16; 0.85]) without an increased risk of valve-related reoperation (HR 2.10 [0.64; 6.96]). When accounting for the occurrence of multiple events in a single patient, the REPAIR group had half the occurrence of major adverse valve-related events (HR 0.51 [0.31; 0.86]). CONCLUSIONS: Although the primary outcome did not significantly differ between the REPAIR and REPLACE groups, the trend is in favour of REPAIR by a significant reduction of valve-related deaths and major bleeding events. Long-term follow-up beyond 4 years is needed to confirm these findings.

Idarucizumab (Praxbind®) for dabigatran reversal in patients undergoing heart transplantation: a cohort of ten patients.

BACKGROUND: Novel oral anticoagulants are used in atrial fibrillation. Idarucizumab has been approved for reversal of dabigatran in situations of life-threatening hemorrhage or emergency surgery. OBJECTIVES: We report a single center experience of ten patients on dabigatran therapy who were given idarucizumab prior to heart transplantation. METHODS & RESULTS: The mean plasma concentration of dabigatran prior to reversal was 139 ± 89 ng/ml. Hemoglobin, hematocrit and platelet levels were decreased after surgery. Surgical procedures were successfully performed with no increased risk, especially regarding bleeding complications. All patients were alive after 90 days. CONCLUSION: Dabigatran reversal with idarucizumab in contexts of emergency surgery/urgent procedures is an attractive and safe option to be taken into consideration for patients with end stage heart disease awaiting transplantation and indication of anticoagulant therapy.

Ruptured right Valsalva sinus into the right atrium due to infective endocarditis: a case report.

Rupture of Valsalva sinus remains a very rare and deadly complication of Valsalva sinus aneurysm with a high mortality rate. We report here the case of a 47-year-old man who presented to the emergency department with acute exercise-induced dyspnea, chest pain, and fever. Transthoracic (TTE) and transesophageal echocardiography (TEE) highlighted a rupture of the right Valsalva sinus in the right atrium due to infective endocarditis. After stabilization of the patient, a successful surgical repair with double pericardial patches was performed.

Experimental evaluation of homemade distal stent graft fenestration for thoracic endovascular aortic repair of type A dissection by a transapical approach.

OBJECTIVE: The use of off-the-shelf stent grafts for thoracic endovascular aortic repair of type A dissections is limited by variability in both the length of the ascending aorta and the location of the proximal intimal tear. This experimental study aimed to assess the feasibility of using a physician-modified thoracic aortic stent graft to treat acute type A dissection by a transapical cardiac approach. METHODS: The experiments were performed on six cadaveric human heart, ascending aorta, aortic arch, and descending aorta specimens. Fenestration was fashioned in each standard tubular Valiant thoracic stent graft (Valiant Captivia; Medtronic Vascular, Santa Rosa, Calif) to match the anatomy of each specimen. Stent grafts of sufficient length were selected to cover the entire ascending aorta and aortic arch. Stent graft diameters in proximal sealing zones were oversized by 5% to 10%. The length of the fenestration was the distance between the left subclavian artery and the proximal edge of the origin of the brachiocephalic trunk with an additional 10 mm. The diameter of the scallop was that of the brachiocephalic trunk with an additional 5 mm on all sides. The length of the covered portion of the stent graft was the distance between coronary arteries and the proximal edge of the origin of the brachiocephalic trunk. Two lateral radiopaque markers were positioned to delineate the distal and lateral edge of the scallop. Another 3-cm radiopaque marker was sutured onto the sheath to ensure accurate radiologic positioning of the scallop on the outer curve of the aorta. The left ventricle and the thoracic aorta were connected to a benchtop aortic pulsatile flow model. A 5-mm 30-degree lens was introduced through the left subclavian artery to monitor the procedure. The customized stent graft was deployed by a transapical approach under fluoroscopic control. RESULTS: Median duration of stent graft modification was 21 minutes (range, 17-40 minutes). All attempts to deploy the homemade proximal scalloped stent graft by a transapical approach were successful. Completion angiography demonstrated patency of the supra-aortic trunks and of the coronary arteries in all cases. Macroscopic evaluation did not identify any deterioration of the customized stent graft. CONCLUSIONS: The use of physician-modified stent grafts is feasible for thoracic endovascular aortic repair of type A dissection by a transapical approach in this model.

Velocimetric ultrasound thermometry applied to myocardium protection monitoring.

Tissue temperature control during cardiac surgery is crucial for myocardial protection. To preserve the tissue, a hypothermic cardioplegia is applied in order to decrease the heart temperature down to around 10°C. The monitoring of the thermal evolution of the myocardium is then of importance to minimize deleterious effects on the heart. The present work aims at evaluating the potential of an ultrasonic velocimetric thermometry on the monitoring of in vitro tissues heating. An indentation process is first proposed to identify the experimental linear relationship linking, in myocardia, the speed of the ultrasonic longitudinal wave to the tissue temperature. An extension of this method based on the echo-tracking principle is then proposed to approach surgical conditions. Temperature changes are measured by monitoring the induced time delays of backscattered ultrasonic echoes. These results are compared to T-type thermocouple reference measurements. They are then discussed in terms of measurement precision and in situ applications.

[Description of the two surgical myocardial revascularisation techniques]. / Description des deux techniques de revascularisation myocardique chirurgicale.

A coronary artery bypass involves taking blood vessels from another part of the patient's body to bypass one or several major coronary stenoses. Coronary artery bypass using cardiopulmonary bypass and off-pump coronary artery bypass are the two methods used to revascularise the heart after a myocardial infarction.

Factors favoring retrograde aortic dissection after endovascular aortic arch repair.

OBJECTIVE: To assess factors predisposing patients to retrograde type A aortic dissection (RTAD) who have undergone hybrid aortic arch repair. METHODS: From 2001 to 2013, 32 patients underwent hybrid aortic arch repair in our department: 19 in zone 1 and 13 in zone 0. Among these patients, 6 experienced RTAD (18.7%): 3 in zone 0 (23%), 3 in zone 1 (15.8%). Preoperative computed tomography scans of these 32 patients were evaluated. A morphologic assessment of the aortic arch, ascending aorta, and aortic root was performed. Other potential risk factors were investigated. Binary logistic regression was performed to test for possible associations with RTAD. RESULTS: Five patients were successfully converted to open repair. Patients who had RTAD were similar to those who did not, across pertinent variables, including age, type of device, diameter of the ascending aorta, and presence of a bicuspid aortic valve (all P > .1). Incidence of RTAD was observed to be higher among women (P = .034), patients with stent-graft oversizing ≥10% (P = .018), and patients treated with a stent-graft of diameter >42 mm (P = .01). Aortic morphology analysis showed that an indexed aortic diameter of ≥20 mm/m(2) (P = .003); aortic root morphology, specifically loss of the sinotubular junction (P = .004); and presence of an aortic arch malformation (P = .03) were correlated with risk of RTAD. Two patients in the zone-0 group with severe angulation (>120°) between the ascending and the transverse aorta suffered RTAD. CONCLUSIONS: The occurrence of RTAD after hybrid aortic arch repair is common. To prevent this complication, preoperative screening of the aortic arch, ascending aorta, and aortic root morphology is critical.

Standardized approach to valve repair using an expansible aortic ring versus mechanical Bentall: early outcomes of the CAVIAAR multicentric prospective cohort study.

OBJECTIVE: The study objective was to compare the 30-day outcomes of a standardized aortic valve repair technique (REPAIR group) associating root remodeling with an expansible aortic ring annuloplasty versus mechanical composite valve and graft (CVG group) replacement in treating aortic root aneurysms. METHODS: A total of 261 consecutive patients with aortic root aneurysm were enrolled in this multicentric prospective cohort (131 in the CVG group, 130 in the REPAIR group) in 20 centers. The main end point is a composite criterion including mortality; reoperation; thromboembolic, hemorrhagic, or infectious events; and heart failure. Secondary end points were major adverse valve-related events. Crude and propensity score adjusted estimates are provided. RESULTS: The mean age was 56.1 years, and the valve was bicuspid in 115 patients (44.7%). The median (interquartile range) preoperative aortic insufficiency grade was 2.0 (1.0-3.0) in the REPAIR group and 3.0 (2.0-3.0) in the CVG group (P = .0002). Thirty-day mortality was 3.8% (n = 5) in both groups (P = 1.00). Despite a learning curve and longer crossclamp times for valve repair (147.7 vs 99.8 minutes, P < .0001), the 2 groups did not differ significantly for the main criterion (odds ratio, 1.31; 95% confidence interval, 0.72-2.40; P = .38) or 30-day mortality (odds ratio, 0.99; 95% confidence interval, 0.28-3053; P = .99), with a trend toward more frequent major adverse valve-related events in the CVG group (odds ratio, 2.52; 95% confidence interval, 0.86-7.40; P = .09). At discharge, 121 patients (96.8%) in the REPAIR group had grade 0 or 1 aortic insufficiency. CONCLUSIONS: A new standardized approach to valve repair, combining an expansible aortic annuloplasty ring with the remodeling technique, presented similar 30-day results to mechanical CVG with a trend toward reducing major adverse valve-related events. Analysis of late outcomes is in process for 3- and 10-year follow-ups.

Remodeling of the aortic root combined to an expansible aortic ring annuloplasty.

Aortic root aneurysms are characterized by dilation of both functional aortic annulus diameters (aortic annular base and sino-tubular junction), preventing coaptation of otherwise pliable valves often associated with cusp prolapse. Multiple techniques of aortic valve sparing procedures try to restore the complex interplay of aortic valve and root function in order to improve durability of the repair. Ideally, procedures should treat dilatation of the aortic annular base, while preserving dynamics of the aortic root with vortices (neosinuses of Valsalva) and root expansibility (interleaflet triangles). We describe a standardized approach, combining the advantages of both the remodeling and reimplantation technique by adding an external subvalvular ring annuloplasty to the physiological remodeling of the aortic root. To address the need for a dedicated aortic annuloplasty device, a new expansible aortic ring was designed in order to achieve a complete and calibrated annuloplasty in diastole, while maintaining systolic expansibility of the aortic root.

Preoperative evaluation in aortic endocarditis: findings on cardiac CT.

OBJECTIVE: The purpose of this study was to study the feasibility and diagnostic capability of preoperative cardiac CT for depicting aortic valvular pseudoaneurysms and vegetations in patients referred for aortic endocarditis requiring surgical intervention. MATERIALS AND METHODS: Consecutive patients presenting with active aortic endocarditis requiring surgical intervention were included. CT scan examinations were performed for assessing coronary artery status. Aortic valves were retrospectively analyzed. Contrast-enhanced CT scans were retrospectively gated to the ECG and obtained without the administration of a beta-blocker. The CT and intraoperative findings were systematically compared. RESULTS: During a 4-year period, 19 consecutive patients (18 men and one woman) were included (mean age +/- SD, 55 +/- 13 years). Results are expressed on a per-patient basis. The sensitivity, specificity, positive predictive value, and negative predictive value of MDCT in depicting aortic valve pseudoaneurysms were 100%, 87.5%, 91.7%, and 100%, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value of the MDCT in depicting the extension of the aortic valve pseudoaneurysms into the intervalvular fibrous body were each 100%. The sensitivity, specificity, positive predictive value, and negative predictive value of MDCT in depicting aortic valve vegetations were 71.4%, 100%, 100%, and 55.5%, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value of MDCT for depicting aortic valve vegetations larger than 1 cm were all 100%. CONCLUSION: Our study shows the feasibility of preoperative CT in aortic infective endocarditis for providing relevant data about the presence and relationships of aortic valvular pseudoaneurysms. A larger prospective study including a systematic comparison with transesophageal echocardiography should be performed to determine the respective value of each technique.

Supravalvular aortic stenosis of the diffuse type: 29 years follow-up after aortic endarterectomy and symmetric enlargement of the ascending aorta and of the three coronary sinuses.

Supravalvular aortic stenosis is a rare congenital anomaly characterized by variable amounts of left ventricular outflow tract obstruction distal to the aortic valve. Macroscopically, it is categorized into three morphologic subtypes: membranous, hourglass, and diffuse. The diffuse type is the most rare, and its surgical repair is the most challenging due to variable length of ascending aorta hypoplasia. Surgical treatment options of supravalvular aortic stenosis are well established for the membranous and hourglass type, whereas they are challenging and less well defined for the diffuse type. We present a case of long-term follow-up (29 years) after a very complex surgical repair of supravalvular aortic stenosis of the diffuse type, with focus on technical aspects. To our knowledge, the present case represents one of the longest follow-up routines in the English language literature of surgical treatment of supravalvular aortic stenosis.

Reconstructive surgery of postinfarction left ventricular aneurysms: techniques and unsolved problems.

The progress in the surgical treatment of postinfarction left ventricular (LV) aneurysm surgery has reduced the operative mortality considerably, while the selection of the optimal LV repair technique remains unclear. Any of the surgical techniques presented in this review has its own advantages and disadvantages. The main goal of this study was to perform a selective literature review of LV aneurysm repair techniques, the most widespread being the linear repair and patch ventriculoplasty.

Early postoperative assessment of coronary artery bypass graft patency and anatomy: value of contrast-enhanced 16-MDCT with retrospectively ECG-gated reconstructions.

OBJECTIVE: The objective of our study was to assess early postoperative patency and anatomy of off-pump coronary artery bypass grafts (CABGs) using retrospectively ECG-gated MDCT. CONCLUSION: Retrospectively ECG-gated MDCT is a promising noninvasive technique with which to assess early postoperative patency and anatomy of CABGs.