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Many young adults require heart valve replacements. Current options for valve replacement in adults include mechanical valves, bioprosthetic valves, or the Ross procedure. Of these, mechanical and bioprosthetic valves are the most common options, although mechanical valve usage predominates in younger adults due to durability, while bioprosthetic valve usage predominates in older adults. Partial heart transplantation is a new method of valvular replacement that can deliver durable and self-repairing valves and allow adult patients freedom from anticoagulation therapy. This procedure involves transplantation of donor heart valves only, permitting expanded utilization of donor hearts as compared with orthotopic heart transplantation. In this review, we discuss the potential benefits of this procedure in adults who elect against the anticoagulation regimen required of mechanical valve replacements, although it has not yet been clinically established. Partial heart transplantation is a promising new therapy for the treatment of pediatric valvular dysfunction. This is a novel technique in the adult population with potential utility for valve replacement in young patients for whom anticoagulation therapy is problematic, such as women who wish to become pregnant, patients with bleeding disorders, and patients with active lifestyles.

Tourniquets have been modified and used for centuries to occlude blood flow to control hemorrhage. More recently, the occlusion of peripheral vessels has been linked to resultant increases in blood pressure, which may provide additional therapeutic potential, particularly during states of low cardiac output.The objective of this study was to investigate a causal relationship between tourniquet application and blood pressure in healthy adults.Healthy adult volunteers were recruited to participate in this IRB-approved study. Each participant met inclusion criteria and demonstrated baseline normotension. Brachial cuff blood pressure and heart rate were recorded pre- and post-tourniquet application to the bilateral legs.Twenty-seven adults aged 22 to 35 years participated and were included in analysis. The average systolic blood pressure was 122 ± 7 mmHg, diastolic blood pressure was 72 ± 9 mmHg, and heart rate was 70 ± 13 bpm. Following bilateral tourniquet application over the femoral vasculature, we observed a statistically significant increase in systolic (7 mmHg, p0.001) and diastolic (4 mmHg, p = 0.05) blood pressures with no significant change in heart rate (2 bpm, p0.05).The elevations in systolic and diastolic blood pressures establish a dependent relationship between tourniquet application to the lower extremities and blood pressure elevation. These results may support new indications for tourniquet-use or extremity vessel occlusion in settings of hemodynamic instability.

The treatment of babies with unrepairable heart valve dysfunction remains an unsolved problem because there are no growing heart valve implants. However, orthotopic heart transplants are known to grow with recipients.Partial heart transplantation is a new approach to delivering growing heart valve implants, which involves transplantation of the part of the heart containing the valves only. In this review, we discuss the benefits of this procedure in children with unrepairable valve dysfunction.Partial heart transplantation can be performed using donor hearts with poor ventricular function and slow progression to donation after cardiac death. This should ameliorate donor heart utilization and avoid both primary orthotopic heart transplantation in children with unrepairable heart valve dysfunction and progression of these children to end-stage heart failure.

Congenital heart disease (CHD) is the most commonly reported birth defect in newborns. Neonates with CHD are more likely to be born prematurely, and a higher proportion of preterm neonates have CHD than their term counterparts. The implications of preterm birth on the cardiac and noncardiac organ systems are vast and require special management considerations. The feasibility of surgical interventions in preterm neonates is frequently limited by patient size and delicacy of immature cardiac tissues. Thus, special care must be taken when considering the appropriate timing and type of cardiac intervention. Despite improvements in neonatal cardiac surgical outcomes, preterm and early term gestational ages and low birthweight remain important risk factors for in-hospital mortality. Understanding the risks of early delivery of neonates with prenatally diagnosed CHD may help guide perioperative management in neonates who are born preterm. In this review, we will describe the risks and benefits of early delivery, postnatal cardiac and noncardiac evaluation and management, surgical considerations, overall outcomes, and future directions regarding optimization of perinatal evaluation and management of fetuses and preterm and early term neonates with CHD.

Introduction Cardiac arrest is the leading cause of natural death in the United States, and most surviving patients suffer from neurological dysfunction. Although this is recognized as a problem, there have been very few changes to the cardiopulmonary resuscitation (CPR) procedure. Tourniquets have been recognized for their ability to increase truncal blood pressure and have been shown to improve CPR outcomes in animal models. However, the relationship between tourniquet application and blood pressure elevation has not been adequately explored in healthy human adults. Objectives The objective of this study is to demonstrate that bilateral, non-invasive, peripheral vascular occlusion in the thighs results in an increased proximal systolic blood pressure ≥ 10 mmHg. Methods This is a single-center, non-blinded clinical trial. Volunteers will be screened for eligibility at least 24 hours before the day of the trial. On the day of the trial, volunteers will undergo an informed consent process. If they choose to participate in the trial after informed consent, their baseline blood pressure will be measured. Volunteers will then have a Combat Application Tourniquet (CAT) applied to each thigh, and the windlasses will be tightened by IRB-approved personnel. Once no pulse can be felt in the lower extremity, blood pressure will be measured in the arm. This will be replicated three times, and the tourniquets will be loosened between trials to allow the volunteers to rest. Any complications that arise during the trial will be handled by the physician that is present. Analysis Changes in systolic blood pressure and diastolic blood pressure will be analyzed using a Shapiro-Wilk test. Then, a one-way repeated measures analysis of variance (ANOVA) will be performed with a Holm-Sidak post-hoc test to determine the mean differences. The significance level will be set to 5% for statistical significance. Registry and registration number Clinicaltrials.gov, NCT05324306.

Bronchial artery revascularization (BAR) during lung transplantation has been hypothesized to improve early tracheal healing and delay the onset of bronchiolitis obliterans syndrome (BOS). We aimed to assess the outcomes of BAR after lung transplantation.Electronic search in Ovid Medline, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Scopus, and Cochrane Controlled Trials Register (CCTR) databases was performed to identify all relevant studies published about lung transplantation with BAR. Studies discussing lung transplantation utilizing BAR were included while those without outcome data such as BOS and survival were excluded. Cohort-level data were extracted and pooled for analysis. A binary outcome meta-analysis of proportions with logit transformation was conducted. Newcastle-Ottawa scale was used for risk of bias assessment.Seven studies were selected for the analysis comprising 143 patients. Mean patient age was 47 (95% CI: 40-55) years. Sixty-one percent (48-72%) were male. Seventy-three percent (65-79%) of patients underwent double lung transplant while 27% (21-25%) underwent single lung transplant. In patients with postoperative angiography, successful BAR was demonstrated in 93% (82-97%) of all assessed conduits. The 30-day/in-hospital mortality was 6% (3-11%). Seventy-nine percent (63-89%) of patients were free from rejection at three months. Eighty-three percent (29-98%) of patients were free from signs of airway ischemia at three and six months. Pooled survival at one year and five years was 87% (78-92%) and 71% (46-87%), respectively, with a mean follow-up time of 21 (3-38) months. Pooled freedom from bronchiolitis obliterans was 86% (77-91%) at two years.While this systematic review and meta-analysis is limited by the available surgeons, institutions, and papers discussing a highly specialized technique, it does show that BAR is a viable technique to minimize BOS and early anastomotic intervention following lung transplantation.

Prior studies have demonstrated deleterious outcomes for physician-patient racial discordance. We explored recipient-surgeon racial concordance and short-term postoperative survival in adults undergoing orthotopic heart transplantation (OHT).The United Network for Organ Sharing (UNOS) database was queried to identify White and Black adult (≥18 years) patients undergoing isolated OHT between 2000 and 2020. Surgeon race was obtained from publicly available images. All non-White and non-Black recipients and surgeons were excluded. Linear probability models were utilized to explore the relationship between recipient-surgeon racial concordance and 30-, 60-, and 90-day post-transplant mortality using a fixed effects approach.A total of 26,133 recipients were identified (mean age 52.79 years, 74.4% male) with 77.65% (n = 20,292) being White and 22.35% (n = 5841) being Black. A total of 662 White surgeons performed 25,946 (97.56%) OHTs during the study period while 17 Black surgeons performed 437 (1.67%) OHTs. Although some evidence of differences across groups was observed in cross-tabular specifications, these differences became insignificant after the inclusion of controls (i.e., comorbidities and fixed effects). This suggests that recipient race and physician race are not correlated with post-OHT survival at 30, 60, or 90 days.Recipient-surgeon racial concordance and discordance among adults undergoing OHT do not appear to impact post-transplant survival. Nor do we observe significant penalties accruing for Black patients overall once controls are accounted for. Given that worse outcomes have historically been demonstrated for Black patients undergoing OHT, further work will be necessary to improve understanding of racial disparities for patients with end-stage heart failure.

Separating wounded serosa by physical barriers is the only clinically approved adjunct for postoperative adhesion prevention. Since the optimal adhesion barrier has not been found, it is essential to improve our pathogenic understanding of adhesion formation and to compare the effects of different barrier materials on tissue and cells. Wistar rats underwent standardized peritoneal damage and were treated either with Seprafilm, Adept, Intercoat, Spraygel, SupraSeal or remained untreated as a control. 14 days postoperatively, the lesions were explanted and histomorphologically analyzed using the European ISO score to evaluate material implants. Striking differences between the material groups were present regarding the inflammation, fibrosis, and foreign body reaction. According to the ISO score, Intercoat and Spraygel were considered as nonirritating to tissue. Adept, Seprafilm, and SupraSeal were assessed as mild-irritating materials. Interestingly, the most effective material in adhesion prevention revealed moderate inflammation accompanied by minor fibrosis. The degree of inflammation to barrier materials does not predict the efficacy in the prevention of adhesions. Histopathological investigations are crucial to improve our understanding of the cellular mechanisms during adhesion formation and elucidate the tissue response to material approaches used in adhesion prevention. This will lead to improved antiadhesive strategies and the development of functional barrier biomaterials. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 598-609, 2018.

There is a scarcity of externally valid data that investigate the utility of operative time, a common clinical parameter, as a predictor of free flap failures. Our aim was to assess whether prolonged operative time correlates with early flap failure following free tissue transfer in the acute care setting using the American College of Surgeons National Surgical Quality Improvement Program database.The 2005-2011 American College of Surgeons National Surgical Quality Improvement Program databases were reviewed for encounters that entailed a free tissue transfer via a CPT algorithm. Patients identified as having a flap loss were compared with people who did not with regards to operative time and patient comorbidities. Patients were subdivided into the following cohort groups with regards to operative time:6 hours, 6-12 hours, and12 hours. Secondary outcome was association between increasing operative time and postoperative complications.Of the 2,008 patients identified, 62 (3.1%) had early flap failure. After multivariable analysis, it was found that progressive operative time was associated with an increased risk of flap failure; 6-12 hours odds ratio was 4.64 and12 hours odds ratio was 5.65 (P = 0.0140). Higher American Society of Anesthesiologists class (P = 0.0042) was also shown to be significantly associated with flap failure. On secondary analysis, increasing operative time was correlated with the following complications: pneumonia, blood transfusions, prolonged ventilation, wound dehiscence, and wound complications.Our results, one of the largest series in the literature, revealed that prolonged operative time was associated with a stepwise increase in the likelihood of early flap failure as well certain postoperative complications. © 2014 Wiley Periodicals, Inc. Microsurgery 37:12-20, 2017.

The postoperative course after major surgical procedures such as cardiothoracic operations is often accompanied by acute metabolic abnormalities due to large volume and temperature shifts. In general, those intervention-induced trauma might cause the use of catecholamines to stabilize hemodynamics. Within the cardiac community, there are still controversial discussions about standardized medical therapy to treat postoperative acidosis, for example, buffering versus nonbuffering for improving catecholaminergic response of myocardial contractility. The aim of this study was to investigate the influence of mild (and thus clinically relevant) acidosis on myocardial contractility and catecholamine response in explanted trabeculae of ovine hearts. Intact trabeculae (n = 24) were isolated from the right ventricle of healthy sheep hearts. Two different groups (group 1: pH = 7.40, n = 9 and group 2: pH = 7.20, n = 13) were investigated, and force amplitudes were measured at frequencies between 30 and 180 beats per minute and increasing catecholamine concentrations (isoprenaline 0-3 × 10(-6) mM). Force-frequency relation experiments in the presence of a physiological and/or mild acidotic pH solution showed no significant differences. Mean force amplitudes normalized to the lowest frequency showing no significant differences in force development between 0.5 and 3 Hz (n = 9 vs. 13, P = n.s.) (0.5 Hz absolute values 3.1 ± 2.6 for pH = 7.40 vs. 3.8 ± 2.6 mN/mm(2) for pH = 7.20, P = n.s.). Moreover, there was no significant difference in relaxation kinetics between the two groups. Furthermore, the experiments showed similar catecholamine responses in both groups. Force amplitudes normalized to baseline and maximum force showed no significant differences in force development between baseline and maximum isoprenaline concentrations (n = 6 vs. 9, P = n.s.) (baseline absolute values 4.3 ± 4.0 for pH = 7.40 vs. 3.9 ± 1.2 mN/mm(2) for pH = 7.20, P = n.s.). Additionally, relaxation kinetics did not show differences after catecholamine stimulation. The presented experiments revealed no significant negative inotropic effects on isometrically contracting ovine trabeculae with mild metabolic acidosis (pH = 7.2) compared with physiological pH (7.4). Additionally, similar catecholamine responses were seen in both groups. Further investigations (e.g., in vivo and/or in failing hearts with reduced compensatory reserves) will be necessary to examine optimal medical treatment for metabolic abnormalities after cardiac surgery.

Background: The CryoMaze procedure is usually limited to endocardial ablation under cardio-pulmonary bypass. Epicardial ablation is considered inferior as endocardial islets of atrial tissue could theoretically remain viable, protected from cryoinjury by epicardial fat and endocardial circulating warm blood. Novel argon-powered cryoprobes with lower ablation temperatures have recently become available. It is unclear if these instruments can reliably induce transmural atrial fibrosis by epicardial cryoablation on the beating heart. Methods: Ten sheep were divided into two equal groups. CryoMaze ablations were applied using an argon-powered cryoprobe with an ablation temperature of −185°C. In the control group, standardized ablations (n = 50) were applied endocardially under cardiopulmonary bypass. In the experimental group, corresponding ablations (n = 50) were applied epicardially on the beating heart. Postoperatively the animals were monitored for 30 days. At necropsy, the lesions were explanted and analyzed histologically for evidence of transmural fibrosis. Results: Two animals in the control group and one animal in the experimental group died prematurely. Autopsy of the remaining animals showed that all lesions (n = 70) had retained their structural integrity. In the control group, histology demonstrated transmural fibrosis in 94% (28/30) of the endocardially applied lesions. In the experimental group, histology demonstrated transmural fibrosis in 95% (38/40) of the epicardially applied lesions. Statistical analysis revealed no significant difference between the two groups (p = 0.96). Conclusion: Argon-powered epicardial cryoablation on the beating heart is as efficient in inducing transmural fibrosis as the traditional technique of endocardial ablation under cardio-pulmonary bypass. (J Card Surg 2011;26:240-243)

Heart failure is one of the fastest-growing epidemics worldwide in health care today. Although a wide variety of animal models exist to create chronic heart failure, there are few truly successful, reproducible models with ischemic dilation and mitral regurgitation. Six healthy sheep (36 ± 5 kg) underwent multiple, strategic coronary artery ligations on the left ventricle (LV). Six to eight ligations were performed transmurally on three of four segments of the LV: anterior, lateral, and posterior. Side branches of the left anterior descending and circumflex arteries were ligated to create multiple, patchy areas of myocardial infarction. Cardiac global and regional systolic function was assessed by echocardiography and cardiac magnetic resonance imaging (MRI). The extent, the characteristics, and the location of the myocardial infarction were qualitatively and quantitatively assessed by late gadolinium enhancement imaging. The overall mortality rate was 16.7% (1/6 animals). Animals who survived showed a significantly reduced ejection fraction (mean 60 ± 5% to 28 ± 7%; P < 0.05); additionally, two out of the remaining five (40%) animals developed mild to moderate mitral regurgitation quantified by cardiac MRI. Furthermore, each animal developed clinical signs of heart failure (tachycardia, dyspnea, and tachypnea) consistent with global, dilated cardiomyopathy noted on MRI. Creating and reproducing a model of global, ischemic cardiomyopathy with functional mitral regurgitation is an arduous task. We have developed a promising model of ischemic heart failure using multiple ligations, which mimics the sequelae of human cardiomyopathy. Our proposed model is highly effective, reproducible, and may be used for experimental research on heart failure (cardiac assist devices, heart transplant, etc.).

We established a stable and reproducible animal model of chronic heart failure (CHF) in sheep to investigate biomolecular changes. Therefore, two biomarkers, adenosine monophosphate-activated protein kinase (AMPK) and vascular endothelial growth factor-A (VEGF-A) were examined to reveal their role during chronic ischemic conditions of the heart. AMPK was studied because it plays an important role in cellular energy homeostasis and its upregulation is associated with myocardial ischemia, whereas VEGF-A was studied because it acts as an important signaling protein for neoangiogenesis. We examined 15 juvenile sheep (mean weight, 78±4kg; control, n=3; ShamOP, n=2; coronary microembolization [CME], n=10). CHF was induced under fluoroscopic guidance by multiple sequential microembolizations (MEs) through bolus injection of polysterol microspheres (90µm, n=25.000) into the left main coronary artery. CME was repeated up to three times at 2- to 3-week intervals until animals started to develop stable signs of CHF. All animals were followed for 3 months. Phosphorylation of AMPK, marking the activated protein form, was detected by Western blotting. VEGF-A and vascular endothelial growth factor-receptor 2 (VEGF-R2) mRNA were detected by real-time polymerase chain reaction. Glyceraldehyde-3-phosphate-dehydrogenase (GAPDH) was used as a reference housekeeping gene. All 10 CHF animals developed clinical signs of CHF as indicated by a significant decrease of cardiac output, decreased ejection fraction, as well as occurrence of tachycardia and tachypnoea. Western blots showed significant phosphorylation of AMPK in CME animals compared to the control group (phospho-adenosine monophosphate-activated protein kinase α) (GAPDH control: 0.0, CME left ventricle [LV]: 0.39±0.20, CME right ventricle [RV]: 0.53±0.30; P0.05). VEGF-A and VEGF-R2 expression in CME animal myocardium was within the range of the control group, but this data did not reach statistical significance due to the small size of this group. While microinjection was performed into the left main coronary artery, phosphorylation of AMPK and expression of VEGF-A and VEGF-R2 were significantly higher in the RV than in the LV. Multiple sequential intracoronary MEs can effectively induce myocardial dysfunction with clinical and biomolecular signs of chronic ischemic cardiomyopathy. Quantitative analysis of biomolecular markers showed a significantly higher phosphorylation of AMPK in CHF animals compared with control myocardium.