[Postoparative Management of the Norwood Procedure].

The Norwood procedure still has a high mortality rate of about 15%, and the surgery and its postoperative management require the meticulous care. Of particular importance is maintaining an appropriate balance between systemic and pulmonary blood flow in the face of ever-changing circulatory conditions, for which various parameters must be understood. These parameters include systolic blood pressure, diastolic blood pressure, mean blood pressure, central venous pressure, oxygen saturation, venous oxygen saturation, lactate, and urine output. I believe that one of the keys to improving outcomes is to make full use of these parameters and to administer appropriate drugs and procedures at the right time. In particular, the pulmonary to body blood flow ratio in the immediate postoperative state and in the stable postoperative state are different, and it is important to predict these while ultimately creating the best circulation for the patient.

[Congenital Heart Surgery in Patients with Coexisting Congenital Anomalies of Respiratory or Digestive System].

Congenital anomaly of respiratory or digestive system have a significant impact on the perioperative management of congenital heart disease. Therefore, it is important to make a long-term treatment strategy. It has been reported that 1-stage surgery is effective for pulmonary artery sling. Simultaneous repair is also useful if significant airway stenosis is present prior to cardiac surgery. In the case of congenital heart disease associated with gastrointestinal anomaly, gastrointestinal surgery precedes in more than 80% of cases. In recent years, though treatments of gastrointestinal atresia have a good outcome, the results of esophageal atresia are still bad. If we choice multi-stage surgery, there is a possibility that we cannot perform cardiac surgery at appropriate time due to postoperative mediastinitis. Therefore, we must consider the timing and method of operation individually. The important thing is to keep a good relationships with related departments and to provide close informed consent to the patient's parents.

Therapeutic targeting of mitochondrial ROS ameliorates murine model of volume overload cardiomyopathy.

Concomitant heart failure is associated with poor clinical outcome in dialysis patients. The arteriovenous shunt, created as vascular access for hemodialysis, increases ventricular volume-overload, predisposing patients to developing cardiac dysfunction. The integral function of mitochondrial respiration is critically important for the heart to cope with hemodynamic overload. The involvement, however, of mitochondrial activity or reactive oxygen species (ROS) in the pathogenesis of ventricular-overload-induced heart failure has not been fully elucidated. We herein report that disorganization of mitochondrial respiration increases mitochondrial ROS production in the volume-overloaded heart, leading to ventricular dysfunction. We adopted the murine arteriovenous fistula (AVF) model, which replicates the cardinal features of volume-overload-induced ventricular dysfunction. Enzymatic assays of cardiac mitochondria revealed that the activities of citrate synthase and NADH-quinone reductase (complex Ⅰ) were preserved in the AVF heart. In contrast, the activity of NADH oxidase supercomplex was significantly compromised, resulting in elevated ROS production. Importantly, the antioxidant N-acetylcysteine prevented the development of ventricular dilatation and cardiac dysfunction, suggesting a pathogenic role for ROS in dialysis-related cardiomyopathy. A cardioprotective effect was also observed in metformin-treated mice, illuminating its potential use in the management of heart failure complicating diabetic patients on dialysis.

Cardiac Rhythm Disturbances in Heterotaxy Syndrome.

OBJECTIVE: Heterotaxy syndrome is associated with complex cardiac malformations and cardiac conduction system abnormalities. Those with right atrial isomerism (RAI) have dual sinus nodes and dual atrioventricular nodes predisposing them to supraventricular tachycardia (SVT). Those with left atrial isomerism (LAI) lack a normal sinus node and are at risk of sinus node dysfunction (SND) and atrioventricular block (AV block). We report the occurrence and risk factors associated with arrhythmias in heterotaxy syndrome. METHODS: A retrospective review of all heterotaxy syndrome patients born and treated at our institution between 2000 and 2014 was performed. RESULTS: A total of 40 patients were identified; 16/40 (40%) with LAI and 24/40 (60%) with RAI. There were 12 deaths during follow-up [LAI 3/16 (19%), RAI 9/24 (38%); p = 0.30]. Twenty-one patients had arrhythmias during a mean follow-up period of 5.4 years; 14/16 (87%) in LAI and 7/24 (29%) in RAI (p < 0.001). Freedom from arrhythmia at 1,3,5 years of age was 75.0%, 37.9%, 22.7% in LAI, and 83.3%, 77.5%, 69.6% in RAI, respectively(p = 0.00261). LAI had a three-fold increase in developing arrhythmias. Left atrial isomerism was the only factor identified to be associated with arrhythmia occurrence. CONCLUSIONS: Arrhythmias were commonly seen in heterotaxy syndrome particularly in left isomerism with more than half of the patients having arrhythmias by 3 years of age. Atrial situs was the only risk factor identified to be associated with arrhythmias, and close follow-up is warranted in these patients.

[Surgical Management of the Patients with Tetralogy of Fallot; Long-term after Initial Repair].

Almost 90% of children with congenital heart disease now reach adulthood due to the improved results of cardiac surgery and medical treatment. Among them, one of particular problems is pulmonary valve regurgitation after tetralogy of Fallot repair. About 20 years ago (1996), the mortality of tetralogy of Fallot has already been relatively good at about 5%, but now it is further reduced to about 2%. For this reason, it is conceivable that more and more adult patients with tetralogy of Fallot will increase in the future. Pulmonary valve regurgitation is often caused by the use of transannular patch repair. Surgical indications for pulmonary valve regurgitation include those with decreased exercise tolerance, right ventricular dysfunction, advanced right ventricular enlargement. We examined treatment strategies, valve selection and catheter valve implantation.

Current Surgical Outcomes of Congenital Heart Surgery for Patients With Down Syndrome in Japan.

BACKGROUND: Current surgical outcomes of congenital heart surgery for patients with Down syndrome are unclear.Methods and Results:Of 29,087 operations between 2008 and 2012 registered in the Japan Congenital Cardiovascular Surgery Database (JCCVSD), 2,651 were carried out for patients with Down syndrome (9%). Of those, 5 major biventricular repair procedures [ventricular septal defect repair (n=752), atrioventricular septal defect repair (n=452), patent ductus arteriosus closure (n=184), atrial septal defect repair (n=167), tetralogy of Fallot (TOF) repair (n=108)], as well as 2 major single ventricular palliations [bidirectional Glenn (n=21) and Fontan operation (n=25)] were selected and their outcomes were compared. The 90-day and in-hospital mortality rates for all 5 major biventricular repair procedures and bidirectional Glenn were similarly low in patients with Down syndrome compared with patients without Down syndrome. On the other hand, mortality after Fontan operation in patients with Down syndrome was significantly higher than in patients without Down syndrome (42/1,558=2.7% vs. 3/25=12.0%, P=0.005). CONCLUSIONS: Although intensive management of pulmonary hypertension is essential, analysis of the JCCVSD revealed favorable early prognostic outcomes after 5 major biventricular procedures and bidirectional Glenn in patients with Down syndrome. Indication of the Fontan operation for patients with Down syndrome should be carefully decided.

Long-Term Results of Bilateral Pulmonary Artery Banding Versus Primary Norwood Procedure.

Bilateral pulmonary artery banding (PAB) has emerged to be an attractive option as an initial procedure for the treatment of hypoplastic left heart syndrome (HLHS), and some centers report excellent survival. However, its usage is variable among institutions and its true efficacy is unknown due to reporting biases. We aimed to describe the results of bilateral PAB use, preoperative risk factors, and long-term outcomes compared with primary Norwood procedure, using a national database. Infants who underwent bilateral PAB or Norwood procedure as an initial palliation for HLHS between January 2008 and December 2012 listed in the Japan Congenital Cardiovascular Surgery Database (JCCVSD) were included. The total number of patients diagnosed with HLHS was 334. Bilateral PABs were performed for 256 patients and primary Norwood procedures for 78 patients, as an initial procedure. Actuarial 5-year survival was 59.0%. The primary Norwood procedure group had better 5-year survival [75.5%; 95% confidence interval (CI) 63.2-84.1] than the bilateral PAB group (75.5 vs. 54.0%, log-rank p < 0.001). However, the bilateral PAB group had more significant risk factors. When the risk-adjusted outcomes were evaluated, there was no significant difference between the primary Norwood group and the bilateral PAB group (76.4 vs. 78.1%, log-rank p = 0.87) in higher volume institutions. The primary Norwood group had better 5-year survival than the bilateral PAB group, but preoperative risk was higher in the bilateral PAB group. Because outcomes are comparable when performed at higher HLHS volume institutions, proper patient selection is important in achieving good long-term result.

Regular Treatment Strategy with a Large Amount of Carvedilol for Heart Failure Improves Biventricular Systolic Failure in a Patient with Repaired Tetralogy of Fallot.

It is widely known that ß-blockers exert beneficial effects on non-ischemic and ischemic systolic heart failure (sHF) in nonstructural hearts. However, whether ß-blockers exert similar effects on sHF associated with congenital heart disease (CHD), particularly in an anatomical right ventricle, remains under debate.Here we report the case of an adult man with repaired tetralogy of Fallot suffering from biventricular heart failure. Treatment with carvedilol directly improved the systolic function of the right and left ventricles. This case report strongly suggests there is potential for carvedilol to exert a beneficial effect on heart failure in CHD. The appropriate titration of carvedilol and patient follow-up for long-term effects are important when treating adult patients with CHD with ß-blockers.

Combined Surgical and Medical Therapy for Candida Prosthetic Endocarditis in a Patient with Repaired Tetralogy of Fallot.

Candida prosthetic endocarditis (CPE) is an uncommon and fatal complication in adults with congenital heart disease. The current guidelines for the management of fungal endocarditis recommend a combination of surgical and medical therapy. However, it still remains uncertain when surgical management in CPE patients should be performed. Therefore, the prognosis of CPE patients is very poor. Here we report a case of CPE in a 31-year-old woman who had undergone surgical repair for tetralogy of Fallot during childhood and pulmonary valve replacement at the age of 21 years. She underwent re-pulmonary valve replacement after being sufficiently sterilized with a 5-week course of antifungal medical therapy, leading to clinical improvement. In CPE patients, it is necessary to perform surgical therapy while suppressing the activity of fungi as much as possible.

Arrhythmias After Fontan Operation with Intra-atrial Lateral Tunnel Versus Extra-cardiac Conduit: A Systematic Review and Meta-analysis.

Current studies on the incidence of arrhythmias after the intra-atrial lateral tunnel (ILT) Fontan operation and the extra-cardiac conduit (ECC) Fontan operation are limited, with controversial results. This systematic review aimed to compare the prevalence of arrhythmias in patients who underwent ECC or ILT Fontan. Relevant studies comparing the incidence of arrhythmias and pacemaker implantation in ILT with ECC were identified through a literature search using MEDLINE, EMBASE, and the cochrane central register of controlled trials. The outcome measures included baseline characteristics, early (≤30 days) and late (>30 days) arrhythmias and pacemaker implantation. 16 publications involving 3499 patients were included. In the meta-analysis, although the overall risk of early arrhythmias was lower for the ILT group, statistically, no significant difference was observed (odds ratio [OR] 0.78; 95% confidence interval [CI] 0.61-1.01; p = 0.06). Similarly, there was no significant difference between the two cohorts in the incidence of postoperative permanent pacemaker therapy (OR 1.36; 95% CI 0.86-2.14; p = 0.19). However, we found significantly increased incidence of late arrhythmias in ILT group compared with ECC group (OR 1.96; 95% CI 1.64-2.35; p < 0.01). Although our systematic review and meta-analysis suggested that there was no significant difference in early arrhythmias and in pacemaker implantation between the ILT and ECC groups, ECC procedure could significantly lower the risk of late arrhythmias after Fontan surgery. Given that some limitations cannot be overcome, well-designed randomized controlled trials are needed to confirm our findings.

Modified Single-Patch Technique Versus Two-Patch Technique for the Repair of Complete Atrioventricular Septal Defect: A Meta-Analysis.

Technical selection for surgical repair of complete atrioventricular septal defect (CAVSD) still remains controversial. This meta-analysis aimed to compare the modified single-patch (MP) technique with the two-patch (TP) technique for patients with CAVSD. Relevant studies comparing the MP technique with the TP technique were identified through a literature search using MEDLINE, EMBASE, Google Scholar, Cochrane Library, and the China National Knowledge Infrastructure databases. The variables were ventricular septal defect (VSD) size, cardiopulmonary bypass (CBP) time, aortic cross-clamp (ACC) time, intensive care unit stay, hospital stay, and other outcomes involving mortality, left ventricular outflow tract obstruction, atrioventricular valve regurgitation, residual septal shunt, atrioventricular block, and reoperation. A random-effect/fixed-effect model was used to summarize the estimates of mean difference/odds ratio with 95% confidence interval. Subgroup analysis stratified by region was performed. Fifteen publications involving 1034 patients were included. This meta-analysis demonstrated that (1) VSD size in the MP group was significantly smaller; (2) CBP time, ACC time, and hospital stay in the MP group experienced improvement; (3) Other postoperative outcomes showed no significant differences between two groups; and (4) The trends in China and other countries were close. The MP and TP techniques had comparable outcomes; however, the MP technique was performed with significantly shorter CBP and ACC times in patients with smaller VSDs. Given this limitation of data, the results of comparison of the two techniques in patients with larger VSDs remain unknown. Further studies are needed.

Tacrolimus-Induced Reversible Cerebral Vasoconstriction Syndrome with Delayed Multi-Segmental Vasoconstriction.

Reversible cerebral vasoconstriction syndrome (RCVS) is a cerebrovascular syndrome characterized by multi-segmental constrictions of the cerebral arteries that resolves spontaneously within 3 months. Although RCVS is considered to be due to transient dysregulation of vascular tone, the exact pathomechanism remains unclear. We describe the case of a 15-year-old girl with RCVS induced by tacrolimus, who developed generalized seizure during the postoperative course of orthotropic heart transplantation. Magnetic resonance imaging at symptom onset showed a few vasoconstrictions accompanying brain edema and convexity subarachnoid hemorrhage. Although her neurological conditions rapidly improved after discontinuing tacrolimus, a repeat magnetic resonance angiogram demonstrated delayed progression of the multi-segmental vasoconstrictions followed by subsequent resolution. Our case demonstrates that cautious observation of the cerebral arteries using magnetic resonance angiography and careful management of vasoconstrictions with vasodilators are necessary for delayed vasoconstrictions even when the clinical symptoms improve.

Experiences With Aggressive Cardiac Rehabilitation in Pediatric Patients Receiving Mechanical Circulatory Supports.

Although some patients with fulminant myocarditis can be rescued owing to the improvements in mechanical circulatory support therapy, there are few reports providing evidence of cardiac rehabilitation during mechanical circulatory supports, particularly among pediatric patients. We treated two pediatric patients who underwent aggressive cardiac rehabilitation during mechanical support. Five days after the initiation of extracorporeal membrane oxygenation therapy aggressive cardiac rehabilitation was started in a 10-year-old girl with fulminant myocarditis. After explantation of the device, she was discharged on postoperative day 23. A 6-year-old girl with fulminant myocarditis started receiving cardiac rehabilitation two days after the initiation of an extracorporeal left ventricular assist device, despite having hemiplegia due to a recent broad stroke. She achieved an exercise capacity of supported walking for 280 meters after 127 days of cardiac rehabilitation and then went abroad to undergo heart transplantation when she was in the best physical condition possible. Early initiation of cardiac rehabilitation may be safe and effective for successful pediatric mechanical circulatory support therapy; this acts as a bridge to explantation or heart transplantation.

Total anomalous pulmonary venous connection with ccTGA and VSD: Can pulmonary artery banding avert pulmonary venous obstruction?

We describe a rare case of infracardiac total anomalous pulmonary venous connection (TAPVC), associated with congenitally corrected transposition of the great arteries (ccTGA) and ventricular septal defect, in which the patient had undergone pulmonary artery banding (PAB) at 16 days of age. She began to have episodes of severe cyanosis while crying, 2 weeks after PAB. Cardiac catheterization at 34 days of age showed severe pulmonary hypertension and a transhepatic pressure gradient of 7 mmHg. The infant underwent TAPVC repair and conventional repair for ccTGA at 35 days of age. Although PAB might have the provisional effect of delaying the manifestation of pulmonary venous obstruction (PVO), it is unable to prevent the development of PVO due to the high resistance of the hepatic sinusoids. Signs of PVO should be closely monitored so that TAPVC can be repaired in a timely fashion.

[Acute Mitral Regurgitation in Infant].

The acute mitral regurgitation of the infants are believed to be very rare until recently. However, there have been increasing number of reports of acute massive mitral regurgitation attributable to rupture of the chordae tendaniae escecially in Japan. If undiagnosed or the optimal treatment including surgery is delayed, it may cause cardiogenic shock and death in infants. Thus pediatricians, pediatric cardiologists and pediatric caridiac surgeons should consider this diagnosis when previously healthy infant suddenly develop cardiorespiratory collapse. It is very important to diagnose early and if there is over moderate mitral regurgitation, the 1st choice will be the mitral valve repair if possible. Pediatric cardiac suregon should be skilled at the mitral valve repair and mitral valve replacement. There are several techniques which are different from the adult operation, so pediatric cardiac surgeon also has to be prepared for these techniques including supraannular mitral valve replacement.

A leadless pacemaker implantation for a patient with systemic right ventricle under ventricular assist device support.

Patients with congenitally corrected transposition of the great arteries (ccTGA) often develop complete atrioventricular block and heart failure due to the abnormal disposition of atrioventricular node and disadvantage of systemic right ventricle. These issues are managed with a pacing system and a ventricular assist device (VAD), respectively. While technological advances offer new treatment strategies, the simultaneous deployment of a leadless pacemaker and a VAD in cases of ccTGA remains unexplored. Here, we present a case of leadless pacemaker implantation for a VAD-supported ccTGA patient. The safety of a leadless pacemaker for a subpulmonary left ventricle and electromagnetic interference between devices are major concerns when implanting a leadless pacemaker; however, the current case overcomes these obstacles. There were no perioperative complications, and both devices were functioning without problems during a one-year follow up. We expect that, even in patients with cardiac complexity such as systemic right ventricle under VAD support, a leadless pacemaker could become the treatment of choice if the indication is appropriate, although careful and close follow up is needed. Learning objective: Technological advances expand treatment strategies and provide significant benefits to patients with adult congenital heart disease (ACHD). However, discussion of the combination of a leadless pacemaker and a ventricular assist device (VAD) is rare. We demonstrated the efficacy of a leadless pacemaker for a subpulmonary left ventricle in a patient with systemic right ventricle on VAD. This approach could be an option even for ACHD patients.

Effect of procedural volume on the outcomes of congenital heart surgery in Japan.

OBJECTIVES: The present study developed a new risk model for congenital heart surgery in Japan and determined the relationship between hospital procedural volume and mortality using the developed model. METHODS: We analyzed 47,164 operations performed between 2013 and 2018 registered in the Japan Cardiovascular Surgery Database-Congenital and created a new risk model to predict the 90-day/in-hospital mortality using the Japanese congenital heart surgery mortality categories and patient characteristics. The observed/expected ratios of mortality were compared among 4 groups based on annual hospital procedural volume (group A [5539 procedures performed in 90 hospitals]: ≤50, group B [9322 procedures in 24 hospitals]: 51-100, group C [13,331 procedures in 21 hospitals]: 101-150, group D [18,972 procedures in 15 hospitals]: ≥151). RESULTS: The overall mortality rate was 2.64%. The new risk model using the surgical mortality category, age-weight categories, urgency, and preoperative mechanical ventilation and inotropic use achieved a c-index of 0.81. The observed/expected ratios based on the new risk model were 1.37 (95% confidence interval, 1.18-1.58), 1.21 (1.08-1.33), 1.04 (0.94-1.14), and 0.78 (0.71-0.86) in groups A, B, C, and D, respectively. In the per-procedure analysis, the observed/expected ratios of the Rastelli, coarctation complex repair, and arterial switch procedures in group A were all more than 3.0. CONCLUSIONS: The risk-adjusted mortality rate for low-volume hospitals was high for not only high-risk but also medium-risk procedures. Although the overall mortality rate for congenital heart surgeries is low in Japan, the observed volume-mortality relationship suggests potential for improvement in surgical outcomes.

Aortic and bronchial perforation caused by a vascular clip 3 years after its placement.

Vascular clips are currently acknowledged as a safe and efficient tool for vessel ligation in every surgical field. Here, we describe a case of massive haemoptysis due to perforation of both the aorta and bronchus, caused by a titanium clip that was placed between them 3 years ago. The present case highlights the rare but life-threatening complications that clips can cause in the mediastinum, especially when placed between a fixed structure and a large blood vessel or respiratory tract.