Risk Factors and Long-Term Prognosis for Chylothorax After Total Cavopulmonary Connection in Children: A Retrospective Study From a Single Center

Background: Chylothorax is a severe complication after total cavopulmonary connection (TCPC) in children. This study was performed to evaluate the incidence, risk factors, and short- and long-term prognosis for chylothorax.Methods: We retrospectively reviewed the electronic records of patients who underwent TCPC between January 2008 and December 2020 in Fuwai Hospital. Patients were divided into two groups based on the occurrence of post-operative chylothorax. Univariate and multivariate analyses were performed to identify risk factors, and long-term survival was estimated by the Kaplan–Meier method.Results: Of 386 patients included in our study, chylothorax occurred in 60 patients (15.5%). Compared with the non-chylothorax group, the prevalence of prolonged intensive care unit (ICU) stay (p = 0.000) and post-operative hospital stay (p = 0.000) were greater in patients with chylothorax. Post-operative adverse events in terms of infection (p = 0.002), ascites (p = 0.001), prolonged pleural effusion (p = 0.000), and diaphragmatic paralysis (p = 0.026) were more frequent in chylothorax patients. The median follow-up duration was 4.0 (2.0, 6.8) years. The chylothorax group had significantly lower survival rates at 1 year (92.4 vs. 99.3%, p < 0.001) and 10 years (84.6 vs. 91.6%, p < 0.001), respectively. Having a right dominant ventricle [odds ratio (OR) = 2.711, 95% confidence interval (CI) = 1.285–5.721, p = 0.009] and a higher peak central venous pressure (CVP) on post-operative day (POD) 0 (OR = 1.116, 95% CI = 1.011–1.233, p = 0.030) were the risk factors for the development of chylothorax after TCPC operation.Conclusion: The incidence of chylothorax in patients undergoing TCPC is lower than previously reported but is associated with poor early- and long-term survival. Having a right dominant ventricle and a higher peak CVP on POD 0 are the risk factors for chylothorax after TCPC operation.

Reappraisal of lung manifestations in the setting of Fontan circulation

Fontan circulation is a well-established palliation in patients with functional single ventricles. Absence of a sub-pulmonary pumping chamber creates a unique physiology in which blood flow is mainly guided by negative intrathoracic and elevated central venous pressures. Various pulmonary anatomic or pathophysiologic changes can jeopardize optimal Fontan circulation. Long-term survival of patients who have undergone the contemporary total cavopulmonary connection is satisfactory. Thorough literature review in conjunction with accumulated clinical experience can lead clinicians to extract conclusions regarding Fontan and lung interactions indicating the purpose of this review.

Multi-institution Assessment of the Accuracy of Cardiac Computed Tomography in Preparation for Superior Cavopulmonary Connection

Background Patients with single ventricle (SV) congenital heart disease (CHD) undergo several interventions in the first years of life. Advanced diagnostics are required for interstage assessment of anatomy, but are associated with significant diagnostic risk. We sought to evaluate image quality, risk, and accuracy of cardiac computed tomography (CCT) for evaluation of anatomy prior to superior cavopulmonary connection (SCPC) compared to surgical findings across 2 institutions. Methods A retrospective evaluation of image quality, risk, and accuracy of pre-SCPC CCT was performed at 2 institutions between January 1, 2010 and September 30, 2016. Results CCT was performed in 90 SV CHD patients with a median age of 4.03 months (interquartile range [IQR] 3.36, 5.33) prior to SCPC. Image quality was optimal (84%) or good (16%) in all patients, without significant discrepancy compared to surgical findings. 7 patients (8%) required interventional cardiac catheterization subsequent to CCT and before surgical intervention. 49% of scans were performed without sedation, 43% of scans were performed with mild to moderate sedation, and 8% of scans were performed with general anesthesia. The median total procedural dose-length product (DLP) was 18 (IQR 14, 26) mGy*cm, estimating an age adjusted radiation dose of 1.4 millisievert (mSv). One minor (1%) adverse event was reported within 24 h of the CCT. Surgical complications were unrelated to the presurgical findings. Conclusions CCT for pre-SCPC evaluation is safe, with excellent accuracy for anatomy at the time of surgical intervention across 2 institutions. In select patients, noninvasive evaluation with CCT may be indicated.

Analysis and regulation of the cardiovascular system of univentricular heart with different configurations of the total cavopulmonary connection

The cardiovascular system (CVS) is a complex mechanism capable of reacting and regulating various changes in external and internal parameters. A particular problem is the study of CVS with univentricular heart. We studied the hemodynamic response of the CVS to the use of various configurations of bypassing the right side of the heart. During our research, we selected three different configurations of the total cavopulmonary connection. All configurations were made from Clear Flex 50 and tested in an experimental workbench. According to the research results, the TCPC-3 configuration is the most optimal. It has symmetrical output values of flows and pressures and there is no significant increase in inlet pressure. The results of this study can be used to optimize the control of the parameters of the ventricular assist device and the total artificial heart.

Case Report: An Anomalous Left Hepatic Venous Connection in a Patient With Unexpected Cyanosis

An anomalous left hepatic venous (LHV) connection is an extremely rare cardiac malformation, and left hepatic venous route abnormalities not associated with other cardiac lesions do not require surgical treatment because they are physiologically benign. However, when venous route abnormalities exist with associated cardiac lesions, the conduct of the cardiac surgical repair must accommodate the abnormal venous anatomy, especially in total cavopulmonary connection patients. Herein, we present a rare case of a 7-year-old Chinese boy about 1 year post bilateral superior vena cava pulmonary anastomosis who presented with severe cyanosis and was referred to our department. However, the patient showed an unexpected gradual decrease in blood oxygen saturation to 60–70% after the extracardiac total cavopulmonary connection (ETCPC) operation. Emergency echocardiography and computed tomography confirmed that the LHV entered the right atrium. Subsequently, the patient undergone completion of a staged TCPC with intra-atrial tunnel technique. This illustrative report highlights the essence of improving the preoperative accurate diagnosis to avoid unplanned reoperation in China, especially for the remote rural areas of eastern countries where the level of health care and services is relatively backward. Failure to identify anomalous LHV connection, in this case, will delay effective treatment past the optimal treatment time.

Catheter ablation of macroreentrant atrial tachycardias following transconduit puncture access in a patient after total cavopulmonary connection with an extracardiac conduit

We present the case of a 23-year-old male diagnosed with a complex congenital heart disease (with single ventricle physiology) which necessitated many surgical interventions including total cavopulmonary connection. The patient presents with recurrent (almost daily) highly symptomatic atrial tachycardia with rapid ventricular rate and poor haemodynamic tolerance. Due to failure of antiarrhythmic drug therapy the patient was referred for catheter ablation. Atrial access was provided following transconduit puncture with a standard transseptal set. Crossing to the atrium with the transseptal introducer was not successful due to resistance from the conduit and the atrial wall. Therefore, balloon dilation of the puncture using a cutting balloon was carried out which resulted in easy crossing to the atrium with a steerable transseptal introducer. Several atrial tachyarrhythmias were induced two of which allowed mapping demonstrating a macroreentrant tachycardia dependent on the cavoannular isthmus as well as a complex fi gure-of-eight circuit involving right pulmonary veins and the right atrial appendage. Linear lesions transecting the critical isthmuses of the two circuits were delivered which rendered the patient noninducible. During a 9-month follow-up period the patient remained arrhythmia free.

Myocardial Perfusion in Hypoplastic Left Heart Syndrome: Risk Factors for the Right Ventricular Microcirculation

Background: The status of the systemic right ventricular coronary microcirculation in hypoplastic left heart syndrome (HLHS) is largely unknown. It is presumed that the systemic right ventricle’s coronary microcirculation exhibits unique pathophysiological characteristics of HLHS in Fontan circulation. The present study sought to quantify myocardial blood flow by cardiac magnetic resonance imaging and evaluate the determinants of microvascular coronary dysfunction and myocardial ischemia in HLHS. Methods: One hundred nineteen HLHS patients (median age, 4.80 years) and 34 healthy volunteers (median age, 5.50 years) underwent follow-up cardiac magnetic resonance imaging ≈1.8 years after total cavopulmonary connection. Right ventricle volumes and function, myocardial perfusion, diffuse fibrosis, and late gadolinium enhancement were assessed in 4 anatomic HLHS subtypes. Myocardial blood flow (MBF) was quantified at rest and during adenosine-induced hyperemia. Coronary conductance was estimated from MBF at rest and catheter-based measurements of mean aortic pressure (n=99). Results: Hyperemic MBF in the systemic ventricle was lower in HLHS compared with controls (1.89±0.57 versus 2.70±0.84 mL/g per min; P <0.001), while MBF at rest normalized by the rate-pressure product, was similar (1.25±0.36 versus 1.19±0.33; P =0.446). Independent risk factors for a reduced hyperemic MBF were an HLHS subtype with mitral stenosis and aortic atresia ( P =0.017), late gadolinium enhancement ( P =0.042), right ventricular diastolic dysfunction ( P =0.005), and increasing age at total cavopulmonary connection ( P =0.022). The coronary conductance correlated negatively with systemic blood oxygen saturation (r, −0.29; P =0.02). The frequency of late gadolinium enhancement increased with age at total cavopulmonary connection ( P =0.014). Conclusions: The coronary microcirculation of the systemic ventricle in young HLHS patients shows significant differences compared with controls. These hypothesis-generating findings on HLHS-specific risk factors for microvascular dysfunction suggest a potential benefit from early relief of frank cyanosis by total cavopulmonary connection.