Clinical experience of reoperative right ventricular outflow tract reconstruction with valved conduits: risk factors for conduit failure in long-term follow-up.

Reconstruction of right ventricular outflow tract in patients with congenital heart disease in various age groups remains a controversial issue. Currently, a little is known about the fate of secondary and subsequent conduit. The aim of the study was to determine risk factors of conduit failure, evaluate long-term conduit survival, find out which type of conduit should be preferred in case of reoperations. We performed a retrospective analysis of a total of 249 records of valved conduit secondary and subsequent replacement in right ventricular outflow tract in 197 patients. Median follow-up was 5.7 years. The study endpoints were defined as conduit explants; balloon dilatation of the graft (excluding balloon dilatation of left/right pulmonary artery), transcatheter pulmonary valve implantation; heart transplantation or death of the patient. There were total of 21 deaths (11% mortality) among 197 patients during the follow-up, 2 patients underwent heart transplant, in 23 implanted conduits pulmonary angioplasty or/including transcatheter pulmonary valve implantation was afterwards performed due to graft failure, conduit had to be explanted in 46 cases. After 28 years follow-up, freedom from graft failure after 5 years was 77%, 48% after 10 years and 21% after 15 years. Reoperative right ventricular outflow tract reconstruction demonstrates good mid-term and acceptable long-term outcomes regardless of the type of conduit implanted. Worse long-term graft survival of secondary and further conduits is associated with younger age of the recipient at implantation, small size of the conduit, younger age of donor and male donor in case of allograft implantation.

Structural Integrity and Cellular Viability of Cryopreserved Allograft Heart Valves in Right Ventricular Outflow Tract Reconstruction: Correlation of Histopathological Changes with Donor Characteristics and Preservation Times

Abstract Introduction: Cryopreserved allograft heart valves (CAHV) show longer event-free survival compared to other types of protheses. However, all patients develop early and/or late allograft failure. Negative predictors are clinical, and there is a lack of evidence whether they correspond with the microscopic structure of CAHV. We assessed histopathological signs of structural degeneration, degree of cellular preservation, and presence of antigen-presenting cells (APC) in CAHV and correlated the changes with donor clinical characteristics, cryopreservation times, and CAHV types and diameters. Methods: Fifty-seven CAHV (48 pulmonary, nine aortic) used for transplantation between November/2017 and May/2019 were included. Donor variables were age, gender, blood group, height, weight, and body surface area (BSA). Types and diameters of CAHV, cold ischemia time, period from decontamination to cryopreservation, and cryopreservation time were recorded. During surgery, arterial wall (n=56) and valvar cusp (n=20) samples were obtained from the CAHV and subjected to microscopy. Microscopic structure was assessed using basic staining methods and immunohistochemistry (IHC). Results: Most of the samples showed signs of degeneration, usually of mild degree, and markedly reduced cellular preservation, more pronounced in aortic CAHV, correlating with arterial APC counts in both basic staining and IHC. There was also a correlation between the degree of degeneration of arterial samples and age, height, weight, and BSA of the donors. These findings were independent of preservation times. Conclusion: CAHV show markedly reduced cellular preservation negatively correlating with the numbers of APC. More preserved CAHV may be therefore prone to stronger immune rejection.

Predictors of mortality after atrial correction of transposition of the great arteries.

OBJECTIVES: To determine the long-term and transplantation-free survival of all patients after atrial correction of transposition of the great arteries (TGA) in the Czech and Slovak republics, including its preoperative and perioperative determinants. METHODS: Retrospective analysis of all 454 consecutive patients after atrial correction of TGA was performed. Of these, 126 (27.8%) were female, median age at operation was 7.4 months (Q1 5.3; Q3 13.3) and 164 (36.1%) underwent the Mustard procedure. The relationships between age, weight, the complexity of TGA, operative technique, additional surgical procedures, immediate postoperative presence of tricuspid regurgitation and revision procedures during follow-up to major composite outcome, as such defined as long-term and transplantation-free survival, were tested. RESULTS: Early 30-day mortality did not differ between the Mustard (9.76%) and Senning (8.97%) cohorts (p=0.866). The long-term and transplantation-free survival, which differed between the Mustard and Senning cohorts in favour of the Senning procedure (HR 0.43; 95% CI 0.21 to 0.87), was shorter in complex TGA (HR 2.4; 95% CI 1.59 to 3.78) and in complex surgical interventions (HR 3.51; 95% CI 2.31 to 5.56). The immediate presence of at least moderate tricuspid regurgitation after correction was associated with a shorter long-term and transplantation-free survival in the univariate but not in the multivariable model. CONCLUSIONS: The lower long-term survival of patients after an atrial switch operation of TGA in the Czech and Slovak republics is associated with greater complexity of TGA, complex surgical interventions and application of the the Mustard operative procedure.

Structural Integrity and Cellular Viability of Cryopreserved Allograft Heart Valves in Right Ventricular Outflow Tract Reconstruction: Correlation of Histopathological Changes with Donor Characteristics and Preservation Times.

INTRODUCTION: Cryopreserved allograft heart valves (CAHV) show longer event-free survival compared to other types of protheses. However, all patients develop early and/or late allograft failure. Negative predictors are clinical, and there is a lack of evidence whether they correspond with the microscopic structure of CAHV. We assessed histopathological signs of structural degeneration, degree of cellular preservation, and presence of antigen-presenting cells (APC) in CAHV and correlated the changes with donor clinical characteristics, cryopreservation times, and CAHV types and diameters. METHODS: Fifty-seven CAHV (48 pulmonary, nine aortic) used for transplantation between November/2017 and May/2019 were included. Donor variables were age, gender, blood group, height, weight, and body surface area (BSA). Types and diameters of CAHV, cold ischemia time, period from decontamination to cryopreservation, and cryopreservation time were recorded. During surgery, arterial wall (n=56) and valvar cusp (n=20) samples were obtained from the CAHV and subjected to microscopy. Microscopic structure was assessed using basic staining methods and immunohistochemistry (IHC). RESULTS: Most of the samples showed signs of degeneration, usually of mild degree, and markedly reduced cellular preservation, more pronounced in aortic CAHV, correlating with arterial APC counts in both basic staining and IHC. There was also a correlation between the degree of degeneration of arterial samples and age, height, weight, and BSA of the donors. These findings were independent of preservation times. CONCLUSION: CAHV show markedly reduced cellular preservation negatively correlating with the numbers of APC. More preserved CAHV may be therefore prone to stronger immune rejection.

Spectrum of postmortem autopsy findings in native and surgically corrected hearts with congenital malformations: a 10-year single-center experience.

OBJECTIVES: We reviewed a spectrum of congenital heart defects assessed in our center between 1/2010 and 4/2020, evaluated their gross anatomy, assessed the age distribution, evaluated performed surgical procedures, and correlated gross and ultrasound findings. METHODS: All necroptic cases and explanted hearts that underwent specialized cardiac autopsy were included in this study. Autopsy findings including gross description of congenital heart defects together with echocardiographic findings were retrospectively assessed. In surgically corrected hearts, the operation records were included as well. All congenital heart defects and surgical procedures were subclassified into main and additional category. RESULTS: The study included 92 necroptic cases of live-born children, 7 stillbirths, 2 cases of young adults, 50 induced abortions, and 5 explanted hearts, with median age 36 weeks. The most frequently encountered leading congenital heart defects were hypoplastic left heart syndrome, aortic stenosis, septal defects, or persistent arterial trunk. Fifty-one patients underwent surgical repair represented mainly by valvuloplasties, aortoplasty, and procedures leading to univentricular circulation. In the native hearts, 4 postnatal and 16 abortion/stillbirth cases showed discordance between gross and sonographic findings, mainly attributed to missed ventricular septal defect. Gestational age of the discordant group was significantly lower compared to the concordant group (P= .007). CONCLUSIONS: Autopsy continues to provide essential information about the morphology of congenital heart defects. However, the encountered congenital heart defects were usually complex, often surgically corrected or evaluated as a result of induced abortion or still birth. Cardiac autopsy therefore places high demands on pathologists with regards to proper gross heart assessment. It is also an invaluable part of quality control in prenatal cardiology.