Search

Objective: To determine the echocardiographic changes in the heart at 3 months and 1 year after pulmonary thromboendarterectomy (PTE) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Patients and Methods: Thirty-two adult patients who underwent PTE for CTEPH at the Mayo Clinic in Rochester, Minn, from 1997 to 2003 were included in the study. All underwent transthoracic echocardiography before surgery. Follow-up echocardiography was performed within 3 months of surgery in 28 patients and 1 year postoperatively in 17 patients. The results were compared with baseline data. Results: Within 3 months after PTE, the right ventricular end-diastolic area decreased from 38.4 +/- 12.8 cm2 to 32.5 +/- 10.4 cm2 (mean difference, 5.8 +/- 10.4 cm2; P = .02). The right ventricular end-systolic area decreased from 30.4 +/- 12.1 cm2 to 24.1 +/- 8.6 cm2 (mean difference, 6.3 +/- 10.1 cm2; P = .008). The right ventricular systolic pressure decreased significantly from 92.6 +/- 22.0 mm Hg to 55.0 +/- 19.8 mm Hg (mean difference, 40.0 +/- 24.8 mm Hg; P < .001). Tricuspid regurgitation (TR) improved from a mean grade of 2.5 +/- 1.2 to 1.2 +/- 1.1 (mean difference, 1.5 +/- 1.0; P < .001). At 12 months, the right ventricular end-diastolic area, right ventricular end-systolic area, right ventricular systolic pressure, and TR also were significantly lower than baseline values. Conclusion: In patients with CTEPH who undergo PTE, echocardiographic measurements of right ventricular size, systolic pressure, and TR show significant improvement immediately after surgery, which is sustained for up to 1 year after surgery. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To analyze the effect of adjuvant perfusion techniques of the distal aorta on the outcome of traumatic thoracic aortic transections. PATIENTS AND METHODS: From 1973 to 2004, 72 patients (mean age, 39 years) with thoracic aortic transections arrived alive at the emergency department. Nineteen patients arrived in extremis and underwent emergency operations, 42 patients were stable and underwent diagnostic evaluation before surgery (4 patients experienced aortic rupture during evaluation), and 11 patients presented more than 24 hours after the accident. Sixteen patients died before aortic repair could be performed. Operative repair was possible in 53 patients (46 stable and 7 in extremis). Interposition graft was performed in 47 patients, and primary repair was performed in 6 patients. Morbidity, mortality, and paraplegia rate were analyzed. RESULTS: Patients in extremis had a mortality rate of 84% (16 of 19), stable patients had a mortality rate of 11% (4 of 38), patients who experienced rupture during evaluation had a mortality rate of 100% (4 of 4), and patients who underwent delayed operation had a mortality rate of 0% (0 of 11). The paraplegia rate with and without adjuvant distal aortic perfusion techniques was 2% (1 of 41 patients) and 33% (4 of 12 patients), respectively (P=.007). Mortality and paraplegia rates were 4% and 4% for partial bypass (n=24), 42% and 33% for the clamp and sew technique (n=12), 0% and 0% for Gott shunt (n=10), and 29% and 0% for full cardiopulmonary bypass (n=7), respectively. CONCLUSIONS: Although thoracic aortic transections remain a highly lethal injury, hemodynamically stable patients have a low operative mortality. Spinal cord injury is decreased by the use of adjuvant perfusion techniques that maintain distal aortic perfusion during cross-clamping of the aorta. [ABSTRACT FROM AUTHOR]

Recent clinical xenotransplantation and human decedent studies demonstrate that clinical hyperacute rejection of genetically engineered porcine organs can be reliably avoided but that antibody mediated rejection (AMR) continues to limit graft survival. We previously identified porcine glycans and proteins which are immunogenic after cardiac xenotransplantation in non-human primates, but the clinical immune response to antigens present in glycan depleted triple knockout (TKO) donor pigs is poorly understood. In this study we use fluorescence barcoded human embryonic kidney cells (HEK) and HEK cell lines expressing porcine glycans (Gal and SDa) or proteins (tetraspanin-29 [CD9], membrane cofactor protein [CD46], protectin, membrane attack complex inhibition factor [CD59], endothelial cell protein C receptor, and Annexin A2) to screen antibody reactivity in human serum from 160 swine veterinarians, a serum source with potential occupational immune challenge from porcine tissues and pathogens. High levels of anti-Gal IgM were present in all samples and lower levels of anti-SDa IgM were present in 41% of samples. IgM binding to porcine proteins, primarily CD9 and CD46, previously identified as immunogenic in pig to non-human primate cardiac xenograft recipients, was detected in 28 of the 160 swine veterinarian samples. These results suggest that barcoded HEK cell lines expressing porcine protein antigens can be useful for screening human patient serum. A comprehensive analysis of sera from clinical xenotransplant recipients to define a panel of commonly immunogenic porcine antigens will likely be necessary to establish an array of porcine non-Gal antigens for effective monitoring of patient immune responses and allow earlier therapies to reverse AMR., (© 2024 The Author(s). Xenotransplantation published by John Wiley & Sons Ltd.)

Background: Heart valve implantation in juvenile sheep to demonstrate biocompatibility and physiologic performance is the accepted model for regulatory approval of new biological heart valves (BHVs). However, this standard model does not detect the immunologic incompatibility between the major xenogeneic antigen, galactose-α-1,3-galactose (Gal), which is present in all current commercial BHVs, and patients who universally produce anti-Gal antibody. This clinical discordance leads to induced anti-Gal antibody in BHV recipients, promoting tissue calcification and premature structural valve degeneration, especially in young patients. The objective of the present study was to develop genetically engineered sheep that, like humans, produce anti-Gal antibody and mirror current clinical immune discordance., Methods: Guide RNA for CRISPR Cas9 nuclease was transfected into sheep fetal fibroblasts, creating a biallelic frame shift mutation in exon 4 of the ovine α-galactosyltransferase gene (GGTA1). Somatic cell nuclear transfer was performed, and cloned embryos were transferred to synchronized recipients. Cloned offspring were analyzed for expression of Gal antigen and spontaneous production of anti-Gal antibody., Results: Two of 4 surviving sheep survived long-term. One of the 2 was devoid of the Gal antigen (GalKO) and expressed cytotoxic anti-Gal antibody by age 2 to 3 months, which increased to clinically relevant levels by 6 months., Conclusions: GalKO sheep represent a new, clinically relevant advanced standard for preclinical testing of BHVs (surgical or transcatheter) by accounting for the first time for human immune responses to residual Gal antigen that persists after current BHV tissue processing. This will identify the consequences of immune disparity preclinically and avoid unexpected past clinical sequelae., (Copyright © 2023 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

There are limited data regarding the surgical management of primary pulmonary artery sarcomas (PPAS) because of their rarity and complicated diagnostic history. The objective of this study was to analyze our institution's long-term surgical management outcomes for PPAS in the absence of a care pathway. From May 1997 to June 2013, 8 patients (mean age 60.6 ± 11.8 years; range, 40-73 years; 5 women and 3 men) underwent surgical intervention for PPAS at our institution. The most common computed tomography finding was a luminal filling defect obstructing the pulmonary artery (PA), without evidence of extraluminal extension. Three patients underwent debulking/pulmonary endarterectomy alone and 5 patients underwent a more radical resection with PA patch angioplasty, PA resection and reconstruction, pulmonary valve replacement, and unilateral pneumonectomy. The mean postoperative survival in this series was 3.8 ± 3.6 years (range, 1-11.9 years), with 2 radical surgical resection patients alive at 4.9 and 11.9 years, respectively. For those patients with incomplete resection, 3-dimensional (3D) models were created to demonstrate the advantage of a preoperative guide for a more complete resection and what it would entail. Six patients had local recurrences with mean disease-free interval of 14 ± 10.9 months (range, 2 months-2.5 years), and 2 patients with re-resections had an overall postoperative survival of 2.8 and 11.9 years, respectively. In our small cohort of PPAS, patients treated with radical surgical resection had better survival. The small number of PPAS cases in this series makes proving this association unlikely but warrants consideration.

Background: Hypertrophic cardiomyopathy (HCM) is characterized by a complex phenotype that is only partly explained by the biological effects of individual genetic variants. The aim of this study was to use proteomic analysis of myocardial tissue to explore the postgenomic phenotype., Methods: Label-free proteomic analysis was used initially to compare protein profiles in myocardial samples from 11 patients with HCM undergoing surgical myectomy with control samples from 6 healthy unused donor hearts. Differentially expressed proteins of interest were validated in myocardial samples from 65 unrelated individuals (HCM [n=51], controls [n=7], and aortic stenosis [n=7]) by the development and use of targeted multiple reaction monitoring-based triple quadrupole mass spectrometry., Results: In this exploratory study, 1586 proteins were identified with 151 proteins differentially expressed in HCM samples compared with controls ( P<0.05). Protein expression profiling showed that many proteins identified in the initial discovery study were associated with metabolism, muscle contraction, calcium regulation, and oxidative stress. Proteins downregulated in HCM versus controls included creatine kinase M-type, fructose-bisphosphate aldolase A, and phosphoglycerate mutase ( P<0.001). Proteins upregulated in HCM included lumican, carbonic anhydrase 3, desmin, α-actin skeletal, and FHL1 (four and a half LIM domain protein 1; P<0.01). Myocardial lumican concentration correlated with the left atrial area (ρ=0.34, P=0.015), late gadolinium enhancement on cardiac magnetic resonance imaging ( P=0.03) and the presence of a pathogenic sarcomere mutation ( P=0.04)., Conclusions: The myocardial proteome of HCM provides supporting evidence for dysregulation of metabolic and structural proteins. The finding that lumican is raised in HCM hearts provides insight into the myocardial fibrosis that characterizes this disease.

Objectives: Surgical strategies to treat drug refractory left ventricular outflow tract obstruction (LVOTO) in hypertrophic cardiomyopathy include septal myectomy (SM) and, less frequently, mitral valve (MV) repair or replacement. The primary aim of this study was to report the surgical technique and management outcomes in a consecutive group of patients with variable phenotypes of hypertrophic cardiomyopathy in a broad national specialist practice., Methods: A total of 203 consecutive patients, 132 men (mean age 48.6 ± 14.6 years) underwent surgery for the management of LVOTO. Surgical approaches included SM (n = 159), SM with MV repair (n = 25), SM with MV replacement (n = 9) and MV replacement alone (n = 10). Specific surgical approaches were performed based on the underlying mechanism of obstruction. Eleven (5.4%) patients had previous alcohol septal ablation for the management of LVOTO. Concomitant non-mitral cardiac procedures were carried out in 22 (10.8%) patients., Results: Operative survival rate was 99.0% with 2 deaths within 30 days. The mean bypass time was 92.9 ± 47.8 min, with a mean length of hospital stay of 10.5 ± 7.8 days. Surgical complications included 3 ventricular septal defects requiring repair (1.5%), 1 Gerbode defect surgically repaired, 2 aortic valve repairs (1.0%), 2 transient ischaemic attacks (1.0%) and 4 strokes (2.0%). Thirty-nine (19.2%) patients had perioperative new-onset atrial fibrillation and 8 (3.9%) patients had unexpected atrioventricular block requiring a permanent pacemaker. Mean resting left ventricular outflow tract gradient improved from 70.6 ± 40.3 mmHg preoperatively to 11.0 ± 10.5 mmHg at 1 year postoperatively (P < 0.001). Mean New York Heart Association class improved from 2.6 ± 0.5 preoperatively to 1.6 ± 0.6 at 1 year after the procedure., Conclusions: In variable phenotypes of LVOTO in hypertrophic cardiomyopathy, an individualized surgical approach provided effective reductions in left ventricular outflow tract gradients and good symptomatic relief with acceptable mortality and morbidity.

Aims: Surgical intervention is used to treat dynamic left ventricular outflow tract obstruction (LVOTO) in hypertrophic cardiomyopathy. This study assesses the effect of different surgical strategies on long-term mortality and morbidity., Methods and Results: In total, 347 patients underwent surgical intervention for LVOTO (1988-2015). Group A (n = 272) underwent septal myectomy; Group B (n = 33), septal myectomy and mitral valve (MV) repair; Group C (n = 22), myectomy and MV replacement; and Group D (n = 20), MV replacement alone. Median follow-up was 5.2 years (interquartile range 1.9-7.9). The mean resting LVOT gradient improved post-operatively from 71.9 ± 39.6 mmHg to 13.4 ± 18.5 mmHg (P < 0.05). Overall, 72.4% of patients improved by >1 New York Heart Association (NYHA) class; 58.9% of patients undergoing MV replacement alone did not improve their NYHA class. There were 5 perioperative deaths and 20 late deaths (>30 days). Survival rates at 1, 5 and 10 years respectively were 98.4, 96.9, 91.9% in Group A; 97.0, 92.4, 61.6% in Group B; 100.0, 100.0, 55.6% in Group C; and 94.7, 85.3, 85.3% in Group D (log-rank, P < 0.05). Long-term (>30 days) complications included atrial fibrillation (29.6%), transient ischaemic attack/stroke (2.4%) and heart failure hospitalisation (3.2%). There were 16 repeat surgical interventions at 3.0 years., Conclusion: Septal myectomy is a safe procedure resulting in symptomatic improvement in the majority of patients. The annual incidence of non-fatal disease-related complications after surgical treatment of LVOTO is relatively high. Patients who underwent MV replacements had poorer outcomes with less symptomatic benefit in spite of a similar reduction in LVOT gradients., (© 2017 The Authors. European Journal of Heart Failure © 2017 European Society of Cardiology.)

Background: This report studies the early and medium-term clinical and echocardiographic outcomes of the Alfieri edge-to-edge mitral valve repair, as adjunctive therapy, to prevent and treat systolic anterior motion (SAM) at the time of septal myectomy (SM) for left ventricular outflow tract obstruction in hypertrophic cardiomyopathy., Methods: From 2009-2015, 11 consecutive patients had a trans-atrial Alfieri repair, to prevent (n = 7) or treat (n = 4) SAM at the time of SM., Results: No patients were lost to follow-up. There were no perioperative or late deaths. Pre-bypass, the mean left ventricular outflow tract gradient, measured directly by simultaneous needle insertion, was 40.7 ± 19.9 mmHg at rest and 115.8 ± 30.4 mmHg on provocation with Isoproterenol, which reduced after SM and Alfieri repair and discontinuation of bypass, to a mean gradient of 8.3 ± 9.8 mmHg at rest and 25.8 ± 9.2 mmHg on provocation. One patient who required mitral valve replacement on day 4, was hospitalized at 2.7 years with heart failure requiring diuresis and remains well at 6 years. One patient developed postoperative atrial fibrillation. There were no other early or late complications. At a median follow-up of 6.6 years (international quartile range 1.2-7.4), clinical and echocardiographic data demonstrated maintained improvement in mean New York Heart Association class from 2.6 ± 0.9 preoperatively to 1.7 ± 0.4 and reduction in mean grade of mitral regurgitation from 2.7 ± 0.8 preoperatively to 0.7 ± 0.6., Conclusions: The Alfieri repair, as adjunctive therapy, for the prevention or treatment of SAM at the time of SM demonstrates satisfactory early and medium-term clinical and echocardiographic outcomes supporting the ongoing utility of this approach., (© 2017 Wiley Periodicals, Inc.)

Cardiac xenotransplantation (CXTx) is a promising solution to the chronic shortage of donor hearts. Recent advancements in immune suppression have greatly improved the survival of heterotopic CXTx, now extended beyond 2 years, and life-supporting kidney XTx. Advances in donor genetic modification (B4GALNT2 and CMAH mutations) with proven Gal-deficient donors expressing human complement regulatory protein(s) have also accelerated, reducing donor pig organ antigenicity. These advances can now be combined and tested in life-supporting orthotopic preclinical studies in nonhuman primates and immunologically appropriate models confirming their efficacy and safety for a clinical CXTx program. Preclinical studies should also allow for organ rejection to develop xenospecific assays and therapies to reverse rejection. The complexity of future clinical CXTx presents a substantial and unique set of regulatory challenges which must be addressed to avoid delay; however, dependent on these prospective life-supporting preclinical studies in NHPs, it appears that the scientific path forward is well defined and the era of clinical CXTx is approaching.

Genetic engineering of donor pigs to eliminate expression of the dominant xenogeneic antigen galactose α1,3 galactose (Gal) has created a sea change in the immunobiology of xenograft rejection. Antibody mediated xenograft rejection of GGTA-1 α-galactosyltransferase (GTKO) deficient organs is now directed to a combination of non-Gal pig protein and carbohydrate antigens. Glycan analysis of GTKO tissues identified no new neo-antigens but detected high levels of N-acetylneuraminic acid (Neu5Gc) modified glycoproteins and glycolipids. Humans produce anti-Neu5Gc antibody and in very limited clinical studies sometimes show an induced anti-Neu5Gc antibody response after challenge with pig tissue. The pathogenicity of anti-Neu5Gc antibody in xenotransplantation is not clear however as non-human transplant models, critical for modelling anti-Gal immunity, do not produce anti-Neu5Gc antibody. Antibody induced after xenotransplantation in non-human primates is directed to an array of pig endothelial cells proteins and to a glycan produced by the pig B4GALNT2 gene. We anticipate that immune suppression will significantly affect the T-cell dependent and independent specificity of an induced antibody response and that donor pigs deficient in synthesis of multiple xenogeneic glycans will be important to future studies., (Copyright © 2015 IJS Publishing Group Limited. Published by Elsevier Ltd. All rights reserved.)

Significant progress in understanding and overcoming cardiac xenograft rejection using a clinically relevant large animal pig-to-baboon model has accelerated in recent years. This advancement is based on improved immune suppression, which attained more effective regulation of B lymphocytes and possibly newer donor genetics. These improvements have enhanced heterotopic cardiac xenograft survival from a few weeks to over 2 years, achieved intrathoracic heterotopic cardiac xenograft survival of 50 days and orthotopic survival of 57 days. This encouraging progress has rekindled interest in xenotransplantation research and refocused efforts on preclinical orthotopic cardiac xenotransplantation., (Copyright © 2015 IJS Publishing Group Limited. All rights reserved.)