development-an-ex-vivo-mitral-valve-evaluation-model-using-pulsatile

Development of an <em>Ex Vivo</em> Mitral Valve Evaluation Model Using a Pulsatile Flow Simulator

Surgical mitral valve repair remains a challenging procedure. Although several repair techniques have been defined, data comparing their hemodynamic ...

Istanbul University-Cerrahpasa

Cardioplegic arrest is one of the most common myocardial protection strategies. A wide variety of cardioplegic solutions are routinely being used. There is an ongoing discussion about the relative effectiveness of these solutions considering myocardial protection. This study aims to investigate the hypothesis that the use of histidine-tryptophan-ketoglutarate (HTK) cardioplegia leads to decreased ischemic damage on myocardium compared with the use of conventional crystalloid cardioplegia. The study population was 32 patients operated on at Başkent University, Department of Cardiovascular Surgery for congenital heart diseases. The first group of 16 patients received conventional crystalloid cardioplegia (KK group) which is a modification of St. Thomas' solution, while the second group of 16 patients received HTK solution (HTK group). The echocardiographic measurements and the laboratory values of the patients were taken as the clinical variables. Right ventricular biopsies were taken from every patient before and after cardioplegic arrest. These biopsies were histopathologically examined for apoptosis using caspase-3 antigen and cell proliferation using Ki-67 antigen. The statistical analysis revealed no significant difference between the two groups regarding the clinical variables, apoptotic indices and proliferation indices. The apoptotic indices in the postcardioplegic arrest biopsies positively correlated with aortic clamp time in the KK group but not in the HTK group. Liver function tests on postoperative day 1 positively correlated with aortic clamp time in both groups. On postoperative day 2, this correlation was sustained in the KK group and ceased in HTK group. The difference in the correlation of apoptotic indices and liver function tests between the groups is accepted as a supportive finding for HTK solution. However, it can be postulated that when the aortic clamp times are similar to those in the present study, the clinical manifestation of the difference between the two solutions would not be significant.

The comparison of the effects of Bretschneider's histidine-tryptophan-ketoglutarate and conventional crystalloid cardioplegia on pediatric myocardium at tissue level.

Is Intrauterine Growth Restriction an Independent Risk Factor for Operations on Congenital Heart Conditions?

This study aims to investigate the incidence and risk factors for chylothorax and to evaluate the effect of chylothorax on the early postoperative outcomes following congenital cardiac surgery.

Risk factors and early outcomes of chylothorax following congenital cardiac surgery: A single-center experience.

In individuals with a single ventricle undergoing evaluation before Fontan surgery, the presence of excessive pulmonary blood flow can contribute to increased pulmonary artery pressure, notably in those who had a Glenn procedure with antegrade pulmonary flow. 28 patients who had previously undergone Glenn anastomosis with antegrade pulmonary blood flow (APBF) and with elevated mean pulmonary artery (mPAP) pressure > 15 mmHg in diagnostic catheter angiography were included in the study. After addressing other anatomical factors that could affect pulmonary artery pressure, APBF was occluded with semi-compliant, Wedge or sizing balloons to measure pulmonary artery pressure accurately. 23 patients (82% of the cohort) advanced to Fontan completion. In this group, median mPAP dropped from 20.5 (IQR 19-22) mmHg to 13 (IQR 12-14) mmHg post-test (p < 0.001). Median PVR post-test was 1.8 (IQR 1.5-2.1) WU m. SpO2 levels decreased from a median of 88% (IQR 86%-93%) pre-test to 80% (IQR 75%-84%) post-test (p < 0.001). In five patients, elevated mPAP post-test occlusion on diagnostic catheter angiography led to non-completion of Fontan circulation. In this group, median pre- and post-test mPAP were 23 mmHg (IQR 21.5-23.5) and 19 mmHg (IQR 18.5-20), respectively (p = 0.038). Median post-test PVR was 3.8 (IQR 3.6-4.5) WU m. SpO2 levels decreased from a median of 79% (IQR 76%-81%) pre-test to 77% (IQR 73.5%-80%) post-test (p = 0.039). Our study presents a specialized approach for patients initially deemed unsuitable for Fontan due to elevated pulmonary artery pressures. We were able to successfully complete the Fontan procedure in the majority of these high-risk cases after temporary balloon occlusion test.

Utility of Balloon Occlusion Testing in Determining Fontan Suitability Among Patients with Elevated Pulmonary Artery Pressure and Additional Antegrade Pulmonary Blood Flow.

Simultaneous Bentall Procedure and Partial Atrioventricular Septal Defect Repair in a 64-Year-Old Patient with Idiopathic Thrombocytopenic Purpura: A Case Report and Literature Review.

Despite advancements in postoperative outcomes after Fontan surgery, there remains a risk of suboptimal outcomes and significant morbidity in the early postoperative period. Anatomical obstructions in the Fontan pathway can lead to prolonged pleural effusion or ascites, cyanosis, and low cardiac output syndrome (LCOS). Transcatheter interventions offer an alternative to early re-surgery for treating these complications. Over a 13-year period, early catheter angiography, performed within 30 days post-index procedure, was administered to 41 patients, identifying anatomical issues that necessitated re-intervention in 39 cases. This led to transcatheter interventions in 37 (10.4%) of the 344 Fontan surgery patients. The median age was 4.8 years (IQR: 4-9.4), and the median weight was 16.5 kg (IQR: 15-25.2), with females comprising 51.4% (19/37) of this group. The primary indications for the procedures were persistent pleural effusion or ascites in 27 patients (66%), LCOS in 8 patients (20%), and cyanosis in 6 patients (14%). Among the 37 undergoing transcatheter intervention, 30 were treated solely with this method and discharged, three died in ICU follow-up, and four required early re-surgery. No procedural mortality was observed. Our findings demonstrate that transcatheter interventions, including stent implantation, balloon angioplasty, and fenestration dilation, are safe and effective in the early post-Fontan period. Therefore, they should be considered an integral part of the management strategy for this patient group.

The Lifesaving Impact of Transcatheter Interventions in the Early Post-Fontan Palliation Period.

Borderline left ventricle cases present considerable difficulties in determining the most effective surgical approaches. The evolution of approaches in the field has shifted from classical systemic pulmonary shunts to orthodox univentricular palliation and has subsequently seen the emergence of biventricular repair concepts. The concept of biventricular repair for borderline left heart conditions has developed through studies that aim to establish predictive scoring systems for identifying appropriate candidates. Despite continuous efforts, a definitive scoring system for guiding this decision is still difficult to find. There is a growing trend to provide neonatal patients with borderline ventricles with options other than univentricular palliation. Several centres have developed personalized strategies, including hybrid and staged ventricular recruitment approaches. These strategies provide sufficient time for personalized decision-making, taking into account the individual circumstances of each patient. This article presents an overview of the changing approaches to borderline left ventricular cases. It discusses the use of predictive scoring systems and emphasizes the advancements in staged strategies that improve the likelihood of successful biventricular repairs.

Contemporary management of borderline left ventricle.

Postoperative junctional ectopic tachycardia (JET) is usually a self-limiting condition; however, when combined with atrioventricular dissociation and postoperative ventricular dysfunction, it may increase morbidity and mortality. This study aimed to determine the overall incidence of JET following congenital heart surgery, to identify patient and procedure-related risk factors, and to evaluate the clinical impact of JET on outcomes.

Junctional Ectopic Tachycardia After Congenital Heart Surgery: Incidence, Risk Factors, and Outcomes.

 In this study, we present our early and mid-term results using two different types of handmade polytetrafluoroethylene (PTFE) valved conduits in patients who require right ventricular outflow reconstruction.  Between March 2021 and May 2024, 72 patients (30 males and 42 females; median age: 69 (IQR: 26-123) months) who underwent implantation of a handmade bicuspid or tricuspid valve PTFE conduit for right ventricular outflow reconstruction were retrospectively analyzed. Preoperative, postoperative, and follow-up echocardiograms were also evaluated.  The first postoperative echocardiography revealed that 11 (36.7%) patients had mild regurgitation, and 3 (10%) patients had moderate regurgitation in the bicuspid group initially, while only 7 (16.7%) of the patients in the tricuspid group had mild regurgitation ( = 0.004). None of the patients required reintervention in the early postoperative period because of conduit dysfunction. In the mid-term follow-up, the mean follow-up duration was 22.4 ± 11 months. PTFE-valved conduit dysfunction was observed in three patients in the bicuspid group, while no dysfunction was observed in the tricuspid group ( = 0.049). Even if the median peak gradient was found to be slightly higher in the tricuspid group [15 (IQR: 0-25) vs. 0 (IQR: 0-15)] ( = 0.032), no conduit dysfunction was reported during follow-up. Kaplan-Meier analysis demonstrated that the tricuspid conduit group maintained 100% freedom from dysfunction during the 24-month follow-up period. In contrast, the bicuspid group had rates of 90%, 87%, and 83% at 6, 12, and 24 months, respectively (log-rank  = 0.016).  The ePTFE valved conduits provide significant advantages in terms of durability, biocompatibility, cost-effectiveness, and hemodynamic performance for right ventricular outflow tract reconstruction in pediatric cardiac surgery. The findings of our study suggest that tricuspid valve design offers better potential for preventing conduit dysfunction.

Article	Year
The comparison of the effects of Bretschneider's histidine-tryptophan-ketoglutarate and conventional crystalloid cardioplegia on pediatric myocardium at tissue level. Artificial organs\| PubMed ID: 23305576	2013
Is Intrauterine Growth Restriction an Independent Risk Factor for Operations on Congenital Heart Conditions? The Annals of thoracic surgery\| PubMed ID: 26777952	2016
Risk factors and early outcomes of chylothorax following congenital cardiac surgery: A single-center experience. Turk gogus kalp damar cerrahisi dergisi\| PubMed ID: 37664767	2023
Utility of Balloon Occlusion Testing in Determining Fontan Suitability Among Patients with Elevated Pulmonary Artery Pressure and Additional Antegrade Pulmonary Blood Flow. Pediatric cardiology\| PubMed ID: 38182891	2024
Simultaneous Bentall Procedure and Partial Atrioventricular Septal Defect Repair in a 64-Year-Old Patient with Idiopathic Thrombocytopenic Purpura: A Case Report and Literature Review. Anatolian journal of cardiology\| PubMed ID: 38234167	2024
The Lifesaving Impact of Transcatheter Interventions in the Early Post-Fontan Palliation Period. Pediatric cardiology\| PubMed ID: 38509208	2024
Contemporary management of borderline left ventricle. European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery\| PubMed ID: 38913849	2024
Junctional Ectopic Tachycardia After Congenital Heart Surgery: Incidence, Risk Factors, and Outcomes. Turk Kardiyoloji Dernegi arsivi : Turk Kardiyoloji Derneginin yayin organidir\| PubMed ID: 39620296	2024
Comparison of Bicuspid and Tricuspid Handmade Polytetrafluoroethylene Valved Conduits: Early and Mid-Term Results. Journal of clinical medicine\| PubMed ID: 40142765	2025

Oktay Korun

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