Assessment of biatrial function in clinically well pediatric bicaval heart transplantation patients by three-dimensional echocardiography.

Atrial size and function are closely correlated with atrial contributions to cardiovascular performance. Therefore, in this study, we aimed to assess atrial size and function in pediatric heart transplantation (HTx) patients using three-dimensional echocardiography (3DE). We enrolled 33 clinically well pediatric HTx patients and 33 healthy controls with a similar distribution of sex and age to the HTx patients. All patients underwent two-dimensional echocardiography (2DE) and 3DE. 2DE- and 3DE-derived biatrial maximal volume (Vmax), minimal volume (Vmin), ejection volume (EV), ejection fraction (EF), volume before atrial contraciton (VpreA), passive EV, passive EF, active EV and active EF were obtained in all patients. The 3D left atrail (LA) Vmax, Vmin and VpreA increased significantly in HTx patients after being indexed by BSA, while 3D LAEV and passive EV decreased significantly (P < 0.05). Moreover, the 3D LAEF, LA passive EF, and LA active EF all decreased significantly in HTx patients (P < 0.05). The 3D right atrial (RA) Vmax, Vmin, and VpreA increased significantly in HTx patients (P < 0.05), while the 3D RAEF and RA passive EF decreased significantly in HTx patients (P < 0.05). 3DE-derived LAVmax, LAVpreA, LA passive EV, LAEF, and LA passive EF were all lower than the corresponding 2D parameters. 3DE-derived RAVpreA, RA passive EV and RAEF were all lower than the corresponding 2D parameters. Atrial sizes and function assessed by 3DE- and 2DE-derived parameters, yield significantly discordant results in pediatric HTx patients. 3DE confirms significantly enlarged atrial sizes and decreased atrial functions in pediatric HTx patients.

Mechanophysiologically active patch for closure of atrial septal defect.

Closure of atrial septal defects (ASDs) can be achieved by various methods right from direct closure to patch closure using various materials viz. pericardium, Dacron and Teflon, to device closure using percutaneous techniques. Although percutaneous techniques are the most commonly practised method in developed countries, a subset of patients will require surgical closure. Various patch materials have been used for long, but all of them have some complications and risks associated with them. We report a case of novel technique of ASD closure done using a pedicled, vascularised and contractile right atrial wall flap.

Over Ten Years of Experience with a Modified Right Atrial Anastomosis in Orthotopic Heart Transplantation: Follow-up and Comparison with the Biatrial and Bicaval Technique.

BACKGROUND: In 1997, a modified right atrial anastomosis (cavoatrial technique) for orthotopic heart transplantation (oHTx) was first developed in our institution. The purpose of this study is to report our long-term experience with this technique compared with biatrial and bicaval technique. METHODS: Retrospectively, 202 consecutive oHTx between 1997 and 2013 were analyzed. The applied transplantation techniques were biatrial (n = 108), bicaval (n = 22), and cavoatrial (n = 72). RESULTS: Demographic data were similar in all groups. The cardiopulmonary bypass and cross-clamp time were significantly shorter in the biatrial group. Follow-up echocardiographic examination showed excellent results in all groups with no relevant differences. After 1 year, occurrence of severe tricuspid regurgitation (biatrial 1.9% vs bicaval 0.0% vs cavoatrial 1.4%) was low in all groups. Rate of permanent pacemaker implantations was also low (12.0% vs 5.0% vs 11.1%). There were no significant differences in survival between the groups. CONCLUSION: The cavoatrial technique can be a safe and simple alternative for heart transplantation. Easy handling and similar reduced postoperative complications encourage the use of this technique.

Atrial function in heart transplant recipients operated with the bicaval technique.

OBJECTIVES: In heart transplantation (HTx) with the bicaval technique the whole right atrium (RA) is donor tissue while the left atrium (LA) consists of both donor and recipient tissue. The aims of the study were to describe atrial function in comparison with healthy controls and to identify determinants of dysfunction. DESIGN: Forty-three patients and 30 controls were retrospectively included. Echocardiography was performed within 24 h of right heart catheterization (RHC) (HTx recipients). RESULTS: The peak longitudinal atrial systolic strain (ɛ) described the atrial reservoir function. The LA and RA reservoir function were reduced versus controls (LA-ɛ 18 ± 8 versus 44 ± 10%; RA-ɛ 22 ± 10 versus 69 ± 17%, p < 0.001). There were moderate relationships between atrial-ɛ and ventricular filling pressure (r = -0.64 for LA-ɛ; r = -0.57 for RA-ɛ). In a multiple regression analysis the LA-ɛ was determined by pulmonary capillary wedge pressure (PCWP) and LA minimum volume index (r = -0.71) while RA-ɛ was dependent on the right ventricular ɛ (r = -0.77). CONCLUSIONS: Atrial reservoir function is markedly reduced in HTx recipients related to elevated PCWP and LA-enlargement in the LA and in the RA impaired longitudinal right ventricular function.

Intravital microscopy to study myocardial engraftment.

Tissue engineering and stem cell transplantation are promising novel therapies for myocardial repair. A major barrier to cell survival after transplantation involves inadequate vascularization. Continuous observation of cardiac tissue engraftment and angiogenesis could help understand these processes and allow for identification of the optimal conditions for these therapeutic interventions. We investigated the ability of a skin-fold chamber model to allow for engraftment of differentiated myocardial tissue in mice. Neonatal atrial and ventricular tissues were implanted in the in vivo chambers. All myocardial implants had a high rate of engraftment (86-95%). Tissue engraftment was preceded by a 'bleeding phase' in both the atrial and ventricular implants. This occurred earlier in ventricular compared with atrial implants. Spontaneous contractions were observed after an average of 13 days after implantation in all chambers but occurred earlier in ventricular compared with atrial implants. The host cells surrounded the myocardial implants circumferentially, but have limited infiltration into these grafts. This is the first report of successful ectopic engraftment of differentiated myocardium using a skin-fold chamber. This model is invaluable for real-time observation of early angiogenesis and tissue growth during in vivo myocardial engineering and myocardial regeneration.

Total venous inflow occlusion and pericardial auto-graft reconstruction for right atrial hemangiosarcoma resection in a dog.

A sizeable right atrial hemangiosarcoma in a 6-year-old Bordeaux dog, World Health Organization (WHO) stage 2, was excised using total venous inflow occlusion. The defect was restored with a non-vascularized pericardial auto-graft. The dog had a disease-free interval of 7 mo. The dog was euthanized 9 months later, at which time there were distant metastases but no indication of local recurrence.

Occlusion totale du remplissage veineux et reconstruction par autogreffe péricardique pour une résection d'un hémangiosarcome atrial droit chez un chien. Un hémangiosarcome atrial droit considérable chez un chien Dogue de Bordeaux âgé de 6 ans, stade 2 de l'Organisation mondiale de la santé (OMS), a été excisé en utilisant l'occlusion totale du remplissage veineux. Le défaut a été rétabli par une autogreffe péricardique non vascularisée. Le chien a connu une période de sept mois sans maladie. Le chien a été euthanasié 9 mois plus tard, lorsque des métastases distantes ont été décelées, mais sans indication d'une récurrence locale.(Traduit par Isabelle Vallières).

Impact of collagen type I turnover on the long-term response to cardiac resynchronization therapy.

AIMS: We investigated whether collagen type I turnover influences the long-term response to cardiac resynchronization therapy (CRT). METHODS AND RESULTS: Serum carboxy-terminal propeptide of procollagen type I or PICP (a marker of collagen type I synthesis) and carboxy-terminal telopeptide of collagen type I or CITP (a marker of collagen type I degradation) were measured in heart failure patients at baseline and after 1 year of CRT. Patients were categorized as responders or non-responders if they increased the distance walked in 6 min by > or <10%, respectively. At baseline, the PICP:CITP ratio, an index of the degree of coupling between collagen type I synthesis and degradation was higher (P = 0.006) in responders than in non-responders. Whereas the PICP:CITP ratio decreased (P= 0.000) after treatment in responders, it remained unchanged in non-responders. Thus, at 1-year, the PICP:CITP ratio was similar in the two groups of patients. A direct correlation (r = 0.289, P = 0.037) was found between the baseline PICP:CITP ratio and the change in the distance walked in 6 min in all patients. Receiver operating characteristics curves showed that a cut-off value of 14.4 for the PICP:CITP ratio provided 70% specificity and 63% sensitivity for the predicting response to CRT with a relative risk of 2.07 (95% confidence interval, 0.98-4.39). CONCLUSION: Collagen type I turnover influences the long-term response to CRT. In addition, the ability of CRT to restore the balance between collagen type I synthesis and degradation is associated with a beneficial response.

Biological pacemaker created by fetal cardiomyocyte transplantation.

BACKGROUND: The aim of this study was to investigate the feasibility of an alternative approach to electronic pacemaker by using spontaneously excitable cell grafts as a biological pacemaker in a large animal model of complete atrioventricular block. METHODS AND RESULTS: Dissociated male human atrial cardiomyocytes including sinus nodal cells were grafted into the free wall of the left ventricle in five female pigs. Three weeks after the injection of cell-grafted solution/control medium the pigs underwent catheter ablation of the atrioventricular node (AV-node). After complete AV block was created, the idioventricular beat rate was more rapid in cell-grafted pigs than that in control pigs (86+/-21 vs. 30+/-10 bpm; P<0.001). Administering of isoprenalin significantly increased idioventricular rate from 86+/-21 to 117+/-18 bpm in the cell-grafted animals (P<0.01). Electrophysiological mapping studies demonstrated that the idioventricular rhythm originated from the cell-injection site. Polymerase chain reaction verifying the existence of SRY DNA in the cell injection site indicated that the grafted male cells were survived. Furthermore, the connexin-43 and N-cadherin positive junctions between donor cardiomyocytes and host cells were identified. CONCLUSION: Xenografted fetal human atrial cardiomyocytes are able to survive and integrate into the host myocardium, and show a pacing function that can be modulated by autonomic agents.

Closure of secundum atrial septal defect with autologous right atrial patch: case report.

BACKGROUND: Although various synthetic materials and pericardium have been used for atrial septal defect (ASD) closure, investigators are continuing to search for an ideal material for this procedure. We report and evaluate a case in which autologous right atrial wall tissue was used for ASD closure. CASE: In this case, we closed a secundum ASD of a 22-year-old woman who also had right atrial enlargement due to the defect. After establishing standard bicaval cannulation and total cardiopulmonary bypass, we opened the right atrium with an oblique incision in a superior position to a standard incision. After examining the secundum ASD, we created a flap on the inferior rim of the atrial wall. A stay suture was stitched between the tip of the flap and the superior rim of the defect, and suturing was continued in a clockwise direction thereafter. Considering the size and shape of the defect, we incised the inferior attachment of the flap, and suturing was completed. Remnants of the flap on the inferior rim were resected, and the right atrium was closed in a similar fashion. RESULTS: During an echocardiographic examination, neither a residual shunt nor perigraft thrombosis was seen on the interatrial septum. The patient was discharged with complete recovery. CONCLUSION: Autologous right atrial patch is an ideal material for ASD closure, especially in patients having a large right atrium. A complete coaptation was achieved because of the muscular nature of the right atrial tissue and its thickness, which is a closer match to the atrial septum than other materials.

Orthotopic cardiac transplantation: comparison of outcome using biatrial, bicaval, and total techniques.

BACKGROUND: For more than 35 years, the biatrial technique of performing orthotopic cardiac transplantation has been the gold standard, and involves anastomoses of donor and recipient atrial cuffs. More recently, however, bicaval and total techniques have been devised in an attempt to improve cardiac anatomy, physiology, and postoperative outcome. A bicaval approach preserves the donor atria and combines the standard left atrial anastomosis with a separate bicaval anastomosis. Total orthotopic heart transplantation involves complete excision of the recipient atria with separate bicaval end-to-end anastomoses, as well as pulmonary venous anastomoses. The aim of this study was to conduct a literature review of studies that compared the three surgical techniques (biatrial, bicaval, and total) for performing orthotopic cardiac transplantation. Numerous outcome variables were evaluated, and included post-transplant survival, atrial dimensions, atrioventricular valvular insufficiency, arrhythmias, pacing requirements, vasopressor requirements, and hospital stay. METHODS: We conducted a Medline (Pubmed) search using the terms "biatrial and cardiac transplantation,""bicaval and cardiac transplantation," and "total technique and cardiac transplantation," which yielded 192 entries: 39 of these were studies that compared surgical techniques and were included in the review. RESULTS: There was overwhelming evidence that the bicaval technique provided anatomic and functional advantages, with improvements in post-transplant survival, atrial geometry, and hemodynamics, as well as decreased valvular insufficiency, arrhythmias, pacing requirements, vasopressor requirements, and hospital stay. CONCLUSIONS: The bicaval technique was superior to both biatrial and total techniques for numerous outcome variables. To further elucidate this issue, a prospective randomized trial comparing the three techniques, with long-term follow-up, is warranted.

Avoiding potential complications in left atrial reduction: partial heart autotransplantation.

Left atrial reduction is a surgical procedure designed in order to eliminate the chronic atrial fibrillation caused by mitral valve disease. However, this surgical technique is not high-risk free. Since a mount of tissue is excised from the left atrium, misalignment of the left atrium can be present. Bleeding of the posterior suture line in this chamber, as well as injury of the circumflex coronary artery may be fatal complications of this technique. Partial heart autotransplantation offers a good solution allowing an excellent visual operative field. The circumflex coronary artery is under direct vision while performing the anastomosis of the left atrium, and the suture line becomes safer and easier.

Intraatrial rerouting by atrial flaps for partial anomalous pulmonary venous return.

We report a new surgical correction technique using an autologous atrial septal flap and anterolateral right atrial wall in a 3-year-old girl with partial anomalous pulmonary venous return and lower margin atrial septal defect. The patient recovered smoothly and is doing well 3 years after the operation.

Atrial transplantation for recurrent cardiac sarcoma.

Cardiac transplantation for sarcomas has met with little success and the surgical treatment remains controversial. We describe the case of a 56-year-old woman who was referred for transplantation after two procedures in which undifferentiated atrial sarcoma was locally excised successfully. The patient underwent atrial homograft transplantation, the first reported to date. Advantages of the procedure include wide atrial resection and no need for immune suppression.

The Cox maze iii procedure: parallel normalization of sinus node dysfunction, improvement of atrial function, and recovery of the cardiac autonomic nervous system.

OBJECTIVE: The Cox maze III procedure includes isolation of the pulmonary veins and multiple incisions in both atria in what corresponds to partial autotransplantation and partial denervation of the heart. The aim of this prospective longitudinal study was to identify physiologic effects of reinnervation on changes in heart rate at rest and in response to various stimulations and on atrial function after the Cox maze III procedure. PATIENTS AND METHODS: Power spectral analysis of heart rate variability, exercise testing, 24-hour Holter monitoring, electrocardiography, and transthoracic and transesophageal echocardiography were performed in 30 adult patients after the combined Cox maze III procedure and mitral valve surgery (maze group). They were prospectively followed up at 1, 3, 6, and 12 months after the operation. The results were compared with those of 15 heart transplant recipients (transplant group) and normal probands (healthy adults, n = 12). RESULTS: The physiologic effects of denervation with no differences in cardiac autonomic activity between the groups were seen early after the operation. Later, evidence of autonomic reinnervation was observed only in the maze group but not in the transplant group. Inappropriate heart rate responses during physical exercise were clearly evident in both groups after 1 and 3 months, with progressive improvement seen between 6 and 12 months only in the maze group. Left atrial function after the Cox maze procedure improved parallel to the recovery of sinus node function. CONCLUSION: Progressive improvement of sinus node function and atrial contractions with significant functional normalization 1 year after the Cox maze procedure corresponded to functional reinnervation and recovery of the autonomic nervous system.

A prospective randomized trial of complete atrioventricular transplantation versus ventricular transplantation with atrioplasty.

BACKGROUND: The standard technique of ventricular transplantation with atrioplasty (SOHT) distorts atrial anatomy. This may compromise diastolic ventricular function, impair atrioventricular valve competence and elevate resting ANP secretion. In contrast, complete atrioventricular anastomosis (CAVT) preserves atrial geometry. METHODS: We evaluated long term outcome in a prospective randomized trial of CAVT vs. SOHT. The primary outcome measures were peak oxygen uptake, atrioventricular valve regurgitation and ANP secretion. RESULTS: 58 recipients (median age 49 years; range 21-64) were consecutively randomized (29 CAVT; 29 SOHT). There were no differences in total ischaemic time, cardiopulmonary bypass time, postoperative bleeding or immunosuppression. Cardiopulmonary exercise tolerance testing was performed by 29 recipients at 742 to 1825 days. Pulmonary function was equivalent. Peak oxygen consumption expressed as a percentage of predicted maximum was 53.5% with CAVT and 63.8% with SOHT (p = 0.14). Echocardiography was performed on 41 recipients at 944 to 1665 days. There was less tricuspid regurgitation with CAVT (3/22 [13.6%] CAVT vs. 10/19 [52.6%] SOHT; p = 0.019). The incidence of mitral regurgitation was similar (5/22 [22.7%] CAVT vs. 4/19 [21.1%] SOHT; p = 0.803). Resting ANP secretion was assessed in 17 recipients at 1013 to 1812 days. All were hemodynamically stable and none had concurrent rejection. Resting ANP secretion was less with CAVT (CAVT: 283 pg/ml; SOHT: 521.4; p = 0.041). CONCLUSIONS: Peak oxygen consumption was not influenced by implantation technique. However, CAVT reduced the incidence of tricuspid regurgitation and attenuated the elevation in resting ANP secretion.

Modification of the Senning repair in a case of transposition of the great arteries with juxtaposition of the atrial appendages.

A further modification of the Senning operation is described in a case of transposition of the great vessels with juxtaposition of the atrial appendages in which the right atrial appendage was excised and used as a free graft in the construction of the venous pathways.

[The ultrastructural characteristics of the reactive changes in the cardiomyocytes of adult rats when cultured in vivo]. / Ul'trastrukturnye osobennosti reaktivnykh izmenenii kardiomiotsitov vzroslykh krys pri kul'tivirovanii in vivo.

60 implantes of the left atrium myocardium were studied on the 1st, 3rd and 6th days of in vivo culture according to F. M. Lazarenko method (outbred laboratory male rats of 200-250g. body weight were used both as donors and recipients). Reactive changes of the cultured cardiomyocytes were assessed by methods of light and electron microscopy. Polymorphic nature of the cardiomyocyte reactive changes with the preservation of its tissue pecific determination was established. Myocardium implant did not form myosymplastic elements, cellular characteristics of organization remained in its implanted pieces. Data concerning degenerating and surviving cardiomyocytes are presented as well as those on cellular forms, identification of which is difficult on the ultrastructural level.