A case of truncus arteriosus with severe heart failure and pulmonary stenosis: bridge to transplant candidacy with surgical correction and a ventricular-assist device.

Ventricular-assist device therapy for small patients with congenital heart disease is challenging due to its complex anatomy and hemodynamics. We describe a 3-year-old patient with heart failure with truncus arteriosus in the palliative stage. The patient underwent palliative right ventricular outflow tract reconstruction following bilateral pulmonary artery banding. At 6 months of age, the patient developed severe truncal valve regurgitation and left ventricular dysfunction. Emergent truncal valve replacement with a mechanical valve was performed, but left ventricular dysfunction persisted. At 3 years of age, the patient developed acute progression of heart failure triggered by influenza infection. The patient was intubated and transferred to our center to determine the indication for heart transplantation. On the second day after admission, signs of multiorgan failure appeared. Emergent ventricular-assist device implantation for both ventricles was performed with truncal valve closure, ventricular septal defect closure, atrial septal defect closure, and re-right ventricular outflow tract reconstruction. The right ventricular-assist device was successfully removed on the seventh postoperative day. Due to the small pulmonary arteries, severe pulmonary stenosis persisted after ventricular-assist device implantation, but it gradually improved with multiple pulmonary angioplasties. The patient was registered in the Japanese organ transplant network and is awaiting a donor organ in a stable condition.

Impaired Relaxation in Induced Pluripotent Stem Cell-Derived Cardiomyocytes with Pathogenic TNNI3 Mutation of Pediatric Restrictive Cardiomyopathy.

BACKGROUND: Restrictive cardiomyopathy (RCM) is characterized by impaired diastolic function with preserved ventricular contraction. Several pathogenic variants in sarcomere genes, including TNNI3, are reported to cause Ca2+ hypersensitivity in cardiomyocytes in overexpression models; however, the pathophysiology of induced pluripotent stem cell (iPSC)-derived cardiomyocytes specific to a patient with RCM remains unknown. METHODS AND RESULTS: We established an iPSC line from a pediatric patient with RCM and a heterozygous TNNI3 missense variant, c.508C>T (p.Arg170Trp; R170W). We conducted genome editing via CRISPR/Cas9 technology to establish an isogenic correction line harboring wild type TNNI3 as well as a homozygous TNNI3-R170W. iPSCs were then differentiated to cardiomyocytes to compare their cellular physiological, structural, and transcriptomic features. Cardiomyocytes differentiated from heterozygous and homozygous TNNI3-R170W iPSC lines demonstrated impaired diastolic function in cell motion analyses as compared with that in cardiomyocytes derived from isogenic-corrected iPSCs and 3 independent healthy iPSC lines. The intracellular Ca2+ oscillation and immunocytochemistry of troponin I were not significantly affected in RCM-cardiomyocytes with either heterozygous or homozygous TNNI3-R170W. Electron microscopy showed that the myofibril and mitochondrial structures appeared to be unaffected. RNA sequencing revealed that pathways associated with cardiac muscle development and contraction, extracellular matrix-receptor interaction, and transforming growth factor-ß were altered in RCM-iPSC-derived cardiomyocytes. CONCLUSIONS: Patient-specific iPSC-derived cardiomyocytes could effectively represent the diastolic dysfunction of RCM. Myofibril structures including troponin I remained unaffected in the monolayer culture system, although gene expression profiles associated with cardiac muscle functions were altered.

Left ventricular assist device temporary explantation as a strategy for infection control in a pediatric patient.

We report a case of temporary Berlin Heart EXCOR® explantation in a pediatric patient with idiopathic dilated cardiomyopathy who suffered an uncontrollable inflow cannulation site infection while on bridge-to-transplantation. Despite failure to thrive and catheter-related infections, once free of the device, the patient was cured of infection using systemic antibiotics and surgical debridement. The patient underwent EXCOR® reimplantation after four months, and is awaiting heart transplantation in stable condition. A life-threatening ventricular assist device-related infection may require device explantation under conditions that may not fulfill conventional explantation criteria despite risks. Temporary explantation can be an effective strategy if isolated systolic dysfunction is managed carefully.

The usefulness of staged extra-anatomic bypass for coarctation of the aorta with arch hypoplasia, from premature neonate to adult.

Various surgical techniques have been developed for coarctation of the aorta. However, coarctation repair in neonates with arch hypoplasia remains challenging. We herein report a case in which a premature neonate under 1500 g with coarctation of the aorta and arch hypoplasia underwent an extra-anatomical bypass at 18 days old. A second extra-anatomical bypass was performed at 3 years of age, and a third extra-anatomic bypass for recurrent coarctation was performed in adulthood. By increasing the size of the graft as the patient grows, extra-anatomic bypass can be a useful surgical option for premature neonates with coarctation and arch hypoplasia.

Risk factors for atrial arrhythmia recurrence after atrial arrhythmia surgery with pulmonary valve replacement.

Objectives: Atrial arrhythmias are a significant cause of late morbidity and mortality in patients after tetralogy of Fallot repair. However, reports on their recurrence following atrial arrhythmia surgery are limited. We aimed to identify the risk factors for atrial arrhythmia recurrence after pulmonary valve replacement (PVR) and arrhythmia surgery. Methods: We reviewed 74 patients with repaired tetralogy of Fallot who underwent PVR for pulmonary insufficiency at our hospital between 2003 and 2021. Twenty-two patients (mean age, 39 years) underwent PVR and atrial arrhythmia surgery. A modified Cox-maze III was performed in 6 patients with chronic atrial fibrillation, and a right-sided maze was performed in 12 with paroxysmal atrial fibrillation, 3 with atrial flutter, and 1 with atrial tachycardia. Atrial arrhythmia recurrence was defined as any documented sustained atrial tachyarrhythmia requiring intervention. The influence of preoperative parameters on recurrence was assessed with the Cox proportional-hazards model. Results: The median follow-up period was 9.2 years (interquartile range, 4.5-12.4). Cardiac death and redo-PVR due to prosthetic valve dysfunction were not observed. Eleven patients had atrial arrhythmia recurrence after discharge. Atrial arrhythmia recurrence-free rates were 68% at 5 years and 51% at 10 years after PVR and arrhythmia surgery. Multivariable analysis revealed that right atrial volume index (hazard ratio, 1.04; 95% confidence interval, 1.01-1.08, P = .009) was a significant risk factor for atrial arrhythmia recurrence after arrhythmia surgery and PVR. Conclusions: Preoperative right atrial volume index was associated with atrial arrhythmia recurrence, which may assist in planning the timing of atrial arrhythmia surgery and PVR.

Pseudoaneurysm after aortopulmonary window repair and bilateral lung transplantation for eisenmenger syndrome: a case report.

BACKGROUND: Aortopulmonary window (APW) is a rare congenital cardiac anomaly characterized by communication between the main pulmonary artery and ascending aorta. There are various surgical techniques, and the short- and long-term results are excellent if the surgical repair is performed early in life. To our knowledge, there have been no reports of pseudoaneurysm after APW repair. Herein, we present a case of a 30-year-old woman with an ascending aortic pseudoaneurysm found at the site of APW repair nine months after the APW repair and bilateral lung transplantation. CASE PRESENTATIONS: A 30-year-old woman presented with APW and Eisenmenger syndrome. The patient underwent APW repair and bilateral lung transplantation. We transected the communication between the aorta and pulmonary artery and closed the aortic side directly with strips of felts. Nine months after the surgery, the patient complained of chest pain. Cardiac computed tomography revealed an ascending aortic pseudoaneurysm at the anastomotic site. Emergent graft replacement of the ascending aorta was performed and the postoperative course was uneventful. CONCLUSIONS: We have presented a case of a pseudoaneurysm at the anastomotic site after APW repair and bilateral lung transplantation. The choice of surgical technique should be based on the patient's background requiring lung transplantation, and in these cases close postoperative follow-up is required.

Novel surgical technique for anomalous origin of a left coronary artery from the right sinus of Valsalva with a single coronary orifice.

Anomalous origin of a left coronary artery from the right sinus of Valsalva with a single coronary orifice is a rare congenital anomaly, which has been associated with myocardial ischemia and sudden death. Surgical repair is recommended upon its detection. A 14-year-old boy was diagnosed with anomalous origin of a left coronary artery from the right sinus of valsalva with a single coronary orifice after a syncope attack. The patient underwent relocation of the left coronary orifice. The postoperative course was uneventful, with no ventricular arrhythmia or syncope. The patient did not develop cardiac ischemia or infarction on exercise Tc-99 m myocardial scintigraphy 8 months after the procedure.

Cardiomyocyte deoxyribonucleic acid damage and cardiac recovery in paediatric dilated cardiomyopathy.

OBJECTIVES: The goal of this study was to identify the clinical significance of the deoxyribonucleic acid (DNA) damage response marker, phosphorylated H2A histone variant X, on the bridge to recovery in low-weight paediatric patients with dilated cardiomyopathy (DCM) after having a Berlin Heart EXCOR implanted. METHODS: Consecutive paediatric patients with DCM who had an EXCOR implanted for DCM at our hospital between 2013 and 2021 were reviewed. Patients were classified into 2 groups according to the degree of DNA damage in the left ventricular cardiomyocytes-the low DNA damage group and the high DNA damage group-using the median value as the threshold. We examined and compared the preoperative factors and histologic findings associated with cardiac functional recovery following the explant procedure in the 2 groups. RESULTS: Competing outcome analysis of 18 patients (median body weight, 6.1 kg) showed that the incidence of an EXCOR explant was 40% at 1 year after the implant procedure. Serial echocardiography revealed significant left ventricular functional recovery in the low DNA damage group 3 months after the implant. The univariable Cox proportional hazards model revealed that the percentage of phosphorylated H2A histone variant X-positive cardiomyocytes was the significant factor associated with cardiac recovery and the EXCOR explant (hazard ratio, 0.16; 95% confidence interval, 0.027-0.51; P = 0.0096). CONCLUSIONS: The degree of DNA damage response to the EXCOR implant may aid in predicting the bridge to recovery with EXCOR among low-weight paediatric patients with DCM.

Univentricular Conversion for Acquired Severe Right Ventricular Failure.

In a 14-year-old boy, prolonged right ventricular (RV) dysfunction due to postmyocarditis cardiomyopathy developed, whereas left ventricular function recovered with conservative treatment. On catheterization, the RV end-diastolic volume index was 184 mL/m2, and mean pulmonary artery pressure was 16 mm Hg. Despite one-and-a-half ventricle repair, RV dilation continued to worsen; therefore, 3 years after the operation, RV exclusion and extracardiac total cavopulmonary connection were performed. Postoperatively, left ventricular function was maintained, and no further RV dilation was observed. Univentricular conversion may be an effective procedure for the treatment of acquired severe isolated right-sided heart failure.

Trans-subclavian approach for Impella CP implantation using the chimney graft in a pediatric patient with fulminant myocarditis during extracorporeal support.

Impella is a device effective for the treatment of cardiogenic shock. However, among small children, its application has limitations due to left ventricle size and vasculature and the turning diameter of the aortic arch. Herein, we report an 11-year-old girl with fulminant myocarditis who was successfully managed with Impella CP implantation via the right subclavian artery using a polyethylene terephthalate chimney graft. Compared with insertion via the femoral artery, this method has several advantages. That is, it can address limitations in aortic arch diameter and facilitate equable fixation of the Impella device in small pediatric patients.

Successful bridge to transplantation with long-term support using Berlin heart EXCOR in a child with failing Fontan.

A 2-year-old girl underwent the Fontan operation for aortic valve stenosis, mitral valve stenosis, a hypo-plastic left ventricle, and a non-compacted right ventricle. The patient's cardiac function reduced gradually thereafter, mainly due to systemic ventricular dysfunction. A Berlin Heart EXCOR (BHE) ventricular assist device with a 10-mL pump was implanted at 4 years of age. After 465 days, BHE support without major complications, the patient underwent heart transplantation. A safe and long-term BHE support was achieved with proper case selection and repeated examinations.

Clinical significance of diastolic dysfunction on outcomes of pulmonary valve replacement for pulmonary insufficiency.

OBJECTIVES: According to the current guidelines of pulmonary valve replacement (PVR) for pulmonary insufficiency, the age at the time of PVR is becoming younger. However, recent studies have shown that the improvements in mortality have leveled off, making it important to suppress the cumulative lifetime risk of morbidity. In this study we aimed to identify the risk factors for morbidity late after PVR. METHODS: Sixty-three patients who underwent PVR for pulmonary insufficiency after intracardiac repair of tetralogy of Fallot or pulmonary atresia with ventricular septal defect at our hospital from 2003 to 2019 were included in this study. Morbidity of PVR included arrhythmia requiring treatment and hospitalization for heart failure. The influence of hemodynamic parameters before PVR was analyzed using the Cox proportional hazards model. RESULTS: The median postoperative follow-up period was 6.5 years. Cardiac death and redo PVR because of prosthetic valve dysfunction were not observed. Twenty-two patients suffered cardiovascular adverse events, including 16 supraventricular tachycardia, 3 sick sinus syndrome/atrioventricular block, 2 sustained ventricular tachycardia, and 1 heart failure hospitalization as first events. In the multivariable analysis, pulmonary end diastolic forward flow (hazard ratio [HR], 7.8; 95% CI, 2.6-23; P < .001), right atrial volume index (HR, 1.02; 95% CI, 1.01-1.04; P = .005), and right atrial pressure (HR, 1.2; 95% CI, 1.01-1.45; P = .042) were significant risk factors for adverse events late after PVR. CONCLUSIONS: End diastolic forward flow, large right atrial volume index, and high right atrial pressure before PVR, which are considered markers of diastolic dysfunction, were significant risk factors for cardiovascular adverse events after PVR.

Inferior-to-Superior Vena Cava Bypass for Baffle Stenosis After Atrial Switch.

An atrial switch operation was successfully performed in an 11-month-old patient with transposition of the great arteries. Good cardiac function was noted on regular follow-ups. A severe inferior vena cava baffle stenosis was detected after a ruptured hepatocellular carcinoma at the age of 39 years. Liver cirrhosis and hepatocellular carcinoma could have been associated with liver congestion resulting from the stenosis. After partial hepatectomy, inferior vena cava-to-superior vena cava bypass was performed without cardiopulmonary bypass. The patient's postoperative course was uneventful, liver enzyme levels decreased to normal limits, and distant recurrence of hepatocellular carcinoma has not been observed.

Risk factors of gynecological bleeding in female patients with left-ventricular assist device.

Women with implantable left-ventricular assist devices (LVADs) experience gynecological bleeding (GYN-bleeding). However, a few studies have investigated female-specific problems. Therefore, this study aimed to identify the risk factors for adverse GYN-bleeding after LVAD implantation. We retrospectively analyzed 59 women (mean age: 41 ± 15 years) with long-term implantable LVAD support (≥ 6 months) at our institution between 2005 and 2018. The history of GYN-bleeding before implantation was defined as abnormal utero-ovarian bleeding, excessive menstruation, uterine fibroids, and endometrial lesions. GYN-bleeding after implantation was defined as a requirement of emergency outpatient visits and/or hospitalization, blood transfusions, hormonal therapy, and/or surgery. Additionally, risk factors for GYN-bleeding were identified using the Cox regression model. Twenty-four GYN-bleeding cases were seen in 15 patients (two times: five patients, three times: two patients, 0.18 events per patient-year). The 1- and 2-year GYN-bleeding-free rates were 84% and 73%, respectively. Twelve patients (17 events) required RBC ≥ 4 units, and five patients (7 events) required FFP ≥ 4 units. Seven patients required pseudomenopausal treatment after blood transfusion, and four patients required surgical treatment. Fifteen patients with GYN-bleeding after implantation were significantly younger than the remaining 44 patients without GYN-bleeding (34 ± 12 years vs. 43 ± 16 years, P = 0.02). Multivariable risk analysis showed a history of GYN-bleeding before implantation was a significant risk factor (hazard ratio 3.7 [1.2-10.6], P = 0.004). Patients with a history of GYN-bleeding before LVAD implantation have a high risk of developing GYN-bleeding after implantation. We should identify the high-risk population and prepare for the management of GYN-bleeding.

Persistent end-diastolic forward flow after pulmonary valve replacement in patients with repaired tetralogy of Fallot.

OBJECTIVES: The clinical significance of persistent end-diastolic forward flow (EDFF) after pulmonary valve replacement (PVR) remains unclear in patients with repaired tetralogy of Fallot. This study aimed to identify the characteristics of these patients and the impact of persistent EDFF on outcomes. METHODS: Of 46 consecutive patients who underwent PVR for moderate to severe pulmonary regurgitation between 2003 and 2019, 23 (50%) did not show EDFF before PVR [group (-)]. In the remaining 23 patients with EDFF before PVR, EDFF was diminished after PVR in 13 (28%) [group (+, -)] and persisted in 10 (22%) [group (+, +)]. The following variables were compared between these 3 groups: (i) preoperative right ventricular (RV) and right atrial volumes measured by magnetic resonance imaging, haemodynamic parameters measured by cardiac catheterization and the degree of RV myocardial fibrosis measured by RV biopsy obtained at PVR and (ii) the post-PVR course, development of atrial arrhythmia and need for intervention. RESULTS: A high RV end-diastolic pressure, a greater right atrial volume index and a greater RV end-systolic volume index before PVR and a high degree of RV fibrosis were significantly associated with persistent EDFF 1 year after PVR. Persistent EDFF was a significant risk factor for postoperative atrial tachyarrhythmia, and catheter ablation and pacemaker implantation were required more frequently in these patients. CONCLUSIONS: Persistent EDFF after PVR could predict a worse prognosis, especially an increased risk of arrhythmia. Close follow-up is required in patients with persistent EDFF for early detection of arrhythmia and prompt reintervention if necessary. CLINICAL TRIAL REGISTRATION NUMBER: Institutional review board of Osaka University Hospital, number 16105.

External compression due to seroma of ventricular assist device outflow graft.

A 45-year-old woman with repaired complex congenital heart disease, who underwent placement of Jarvik 2000, a ventricular assist device (VAD) for 4 years, experienced abdominal pain due to outflow graft compression caused by seroma formation between the outflow graft and ringed Gore-Tex graft. We exchanged the pump of Jarvik 2000 and punched several small holes in the new ringed Gore-Tex graft. Seroma formation between the two grafts should be considered as a cause of outflow graft obstruction in patients with the long-term support of VAD, and additional surgical interventions to the ringed Gore-Tex graft may prevent this complication.

Pediatric patient with restrictive cardiomyopathy on staged biventricular assist device support with Berlin Heart EXCOR® underwent heart transplantation successfully: the first case in Japan.

Pure restrictive cardiomyopathy is a strong risk factor for poor outcomes in children with cardiomyopathy on ventricular assist devices. Owing to concomitant right heart failure, children with end-staged restrictive cardiomyopathy who are supported with a ventricular assist device often require a biventricular assist device, which is another risk factor for waitlist mortality in heart transplantation candidates. Herein, we report the case of a 3-year-old boy with pure restrictive cardiomyopathy who successfully underwent heart transplantation after 12 months of support with staged biventricular assist devices. Owing to the progression of diastolic dysfunction, the left ventricular assist device could not provide adequate circulation support. Despite the provision of biventricular assist device support, the patient required a complex management strategy that involved balancing the left and right ventricular assist device supports. We were able to stabilize the patient by careful synchronization of the supports and proceeded to heart transplantation. TRIAL REGISTRATION: Clinical Registration No.: Institutional Review Board of Osaka University Hospital, approval no. 16105.

Contained rupture of right ventricular outflow tract after Rastelli-type operation.

This report describes a 3-year-old infant with post-operative mediastinitis complicated by a contained rupture of the right ventricle. A contained rupture is recognised as the huge pulsating prominence of the anterior chest wall. CT confirmed blood communication between the right ventricular outflow tract and the cavity surrounded by the pectoral major musculocutaneous flap. This is a significant case in which severe adhesion between the right ventricle and the musculocutaneous flap could maintain her stable haemodynamics with a pulsating prominence.

Long-term results after palliative intra-cardiac repair for tetralogy of Fallot and diminutive pulmonary arteries.

BACKGROUND: In patients with tetralogy of Fallot with the diminutive pulmonary arteries, we sometimes have to give up the complete intra-cardiac repair due to insufficient growth of the pulmonary arteries. We have carried out palliative intra-cardiac repair using a fenestrated patch. METHODS: Of all 202 patients with tetralogy of Fallot in our centre since 1996, five patients (2.5%) with the diminutive pulmonary arteries underwent palliative intra-cardiac repair using a fenestrated patch. Mean operative age was 1.8 years. Previous operation was Blalock-Taussig shunt in 4. At operation, the ventricular septal defect was closed using a fenestrated patch and the right ventricular outflow tract was enlarged. Follow-up period was 9.8 ± 2.6 years. RESULTS: There were no operative and late deaths. Fenestration closed spontaneously on its own in four patients 2.7 ± 2.1 years after the intra-cardiac repair with a stable haemodynamics; however, the last patient with the smallest pulmonary artery index had supra-systemic pressure of the right ventricle post-operatively. The fenestration was emergently enlarged. Systemic arterial oxygen saturation was significantly and dramatically increased from 83.5 to 94% after the palliative intra-cardiac repair, and to 98% at the long term. A ratio of systolic pressure of the right ventricle to the left was significantly decreased to 0.76 ± 0.12 at the long term. Now all five patients were Ross classification class I. CONCLUSION: Although frequent catheter and surgical interventions were needed after the palliative intra-cardiac repair, this repair might be a choice improving quality of life with good results in patients with tetralogy of Fallot associated with the diminutive pulmonary arteries.

Successful Truncal Valve Replacement After Truncal Valve Repairs.

The surgical management of severe truncal valvular dysfunction is still challenging in neonates with persistent truncus arteriosus. This report describes a 14-day-old neonate with severe truncal valve insufficiency successfully undergoing truncal valve repairs, and followed by valve replacement at the age of 4 years. The truncal valve was quadricuspid with two large and two small leaflets, and all leaflets had severe dysplastic and myxomatous changes. We performed leaflet extension and bicuspidization valvuloplasty for this valve. This patient obtained somatic growth for 4 years without heart failure symptoms, and safely underwent prosthetic valve replacement. This technique would be effective for truncal valve dysfunction in neonates as the life-saving and the bridging procedure to valve replacement.