Pulmonary Venous Gradients in Healthy Controls and Following the Repair of Total Anomalous Pulmonary Venous Return.

The percent of children who can achieve a normal and physiologic pulmonary venous gradient and flow following the repair of Total Anomalous Pulmonary Venous Return (TAPVR) is not known. Pulmonary venous confluence gradients from infants with supra-, infra-, or mixed TAPVR, repaired using a direct anastomotic connection were measured. Data from age, weight, and gender-matched controls established the normal pulmonary venous gradient range (0.30-0.94 mmHg). TAPVR subjects were divided into three groups: (I) pulmonary venous gradient < 2 × normal with multiphasic flow (II) pulmonary venous gradient > 2 × normal with multiphasic flow, and (III) pulmonary venous gradient > 2 × normal with monophasic flow. From 63 children following TAPVR repair and 63 matched controls, pulmonary venous gradients were significantly lower [0.5 mmHg (IQR:0.4, 0.6) vs 1.6 mmHg (IQR:1.0, 2.4); p < 0.001], and multiphasic flow more frequent (100 vs. 84.1%; p = 0.001) within the control group. There were 38 children (60.3%) in group I, 15 (23.8%) in group II, and 10 (15.8%) in group III. Children in Group I were significantly older at the time of repair, had shorter cardiopulmonary bypass times, and did not utilize deep hypothermic circulatory arrest (DHCA). Multivariate analysis confirmed that avoiding DHCA [Odds Ratio 0.931 (0.913,0.994; p = 0.002)] and shorter cardiopulmonary bypass times [Odds Ratio 0.962 (0.861,0.968; p = 0.02)] during repair were associated with the lowest pulmonary venous gradients and multiphasic flow. Following TAPVR repair with a direct anastomosis, the majority of children can achieve a gradient two times normal or less with multiphasic pulmonary venous flow.

A modified approach in the repair of type I and II truncus arteriosus to promote branch pulmonary arterial growth and limit early reoperation.

Objective: Maintaining adequate branch pulmonary arterial growth is critical in preventing early (<3 years) right ventricular outflow tract reoperation after the repair of truncus arteriosus. We hypothesized that a modified truncus arteriosus repair keeping the branch pulmonary arteries in situ would promote branch pulmonary arterial growth and limit early right ventricular outflow tract reoperation. Methods: For infants requiring repair for type I and II truncus arteriosus, the truncal root was septated through a hockey stick incision keeping the branch pulmonary arteries in situ, the ventricular septal defect was closed, and a short aortic homograft was used to reconstruct the right ventricular outflow tract. Echocardiograms measured preoperative and follow-up branch pulmonary artery diameter. Results: Between 1998 and 2020, 41 infants were repaired using the modified approach (type I, 28; type II, 13). With a median follow-up of 11.6 (interquartile range, 3.1-15.5) years, there was no significant change between preoperative left pulmonary artery and right pulmonary artery Z-scores and their corresponding follow-up measurement (left pulmonary artery: 0.97, interquartile range, 0.6-1.6 vs left pulmonary artery: 1.4, interquartile range, -0.3 to 1.9) (right pulmonary artery: 0.6, interquartile range, -0.4 to 1.7 vs right pulmonary artery: 0.3 interquartile range, 0.5-0.9). Only 7.3% (n = 2) of follow-up right pulmonary artery Z-scores were less than 2.5 Z-scores below preoperative measurements. Four children (9.8%) required early right ventricular outflow tract reoperation. On multivariable analysis, larger conduit Z-scores were associated with greater time to right ventricular outflow tract reoperation (hazard ratio, 0.55, confidence interval, 0.307-0.984; P = .043). Conclusions: Maintaining the branch pulmonary arteries in situ at initial truncus arteriosus repair allows for branch pulmonary arterial growth, limiting early right ventricular outflow tract reoperation.

Intraoperative Cortical Asynchrony Predicts Abnormal Postoperative Electroencephalogram.

BACKGROUND: Postoperative electroencephalograms (EEGs) can identify seizure activity and neurologic dysfunction in high-risk neonates requiring cardiac surgical procedures. Although intraoperative EEG monitoring is uncommon, variations in cerebral blood flow and temperature during antegrade cerebral perfusion (ACP) can manifest as cortical asynchrony during EEG monitoring. We hypothesized that intraoperative EEG cortical asynchrony would identify neonates at risk for abnormal postoperative EEG tracings. METHODS: Neonates requiring ACP for cardiac repair or palliation had continuous baseline, intraoperative, and postoperative hemodynamic and EEG monitoring. Synchronous and asynchronous cortical bursts were quantified during (1) cooling before ACP, (2) ACP, and (3) rewarming. Asynchronous bursts were defined as interhemispheric variations in electrical voltage or frequency. Neonates were divided into 2 groups, those with and without an abnormal postoperative EEG, which was defined as either persistent asynchrony for more than 2 hours or seizure activity on EEG. RESULTS: Among 40 neonates, 296 asynchronous bursts were noted, most commonly during rewarming. Eight (20%) neonates had an abnormal postoperative EEG (seizure activity, n = 3; persistent asynchrony, n = 5). Baseline demographics and intraoperative hemodynamics were similar between the groups. However, the total number of intraoperative asynchronous bursts was greater in neonates with an abnormal postoperative EEG (17 [11, IQR:24] vs 3 [IQR:1, 7]; P < .001). Multivariate analysis confirmed that the number of asynchronous bursts was independently associated with an abnormal postoperative EEG (odds ratio,1.35; confidence interval,:1.10, 1.65; P = .004). CONCLUSIONS: Neonates with a greater number of intraoperative asynchronous cortical bursts had an abnormal postoperative EEG.

Reassessment of the Location of the Conduction System in Atrioventricular Septal Defect Using Phase-Contrast Computed Tomography.

The location of the atrioventricular conduction axis in the setting of atrioventricular septal defect has previously been shown by histology and intraoperative recordings. We have now reassessed the arrangement using phase-contrast computed tomography, aiming to provide precise measurements so as to optimize future surgical repairs. We used the system based on an X-ray Talbot grating interferometer using the beamline BL20B2 in a SPring-8 synchrotron radiation facility available in Japan. We analyzed 18 specimens. The atrioventricular node was found within a nodal triangle 1.7 mm from the coronary sinus, with 95% confidence intervals from 1.45 to 2.0 millimeters. The depth of the node from the right atrial endocardium was 1.0 mm, with 95% confidence intervals from 0.73 to 1.34 mm. The overall length of the scooped-out ventricular septum was 30.8 mm, with 95% confidence intervals from 27.5 to 34.1 millimeters. The length from the inferior atrioventricular junction to the take-off of the right bundle branch was 12.8 mm, with 95% confidence intervals from 11.12 to 14.38 mm, giving a ratio of 0.43 for the extent of the axis along the inferior septum, with 95% confidence intervals of 0.38-0.48. The length of the non-branching bundle was 6.6 mm, with 95% confidence intervals from 5.57 to 7.7 mm. The proportion of septum occupied by the non-branching bundle was 0.22, with 95% confidence intervals from 0.18 to 0.26. Our findings confirm previous histological studies, extending them by providing precise measurements to guide placement of sutures during surgical repair.

Effect of Long-term Administration of Prostaglandin E1 on Morphologic Changes in Ductus Arteriosus.

BACKGROUND: To improve survival of patients with hypoplastic left heart syndrome, combination therapy with bilateral pulmonary artery banding and prostaglandin E1 (PGE1)-mediated ductal patency was developed as an alternative for high-risk neonates in Japan. However, the effect of long-term PGE1 administration on ductus arteriosus remains unclear. Synchrotron radiation-based X-ray phase-contrast tomography (XPCT) enables clear visualization of soft tissues at an approximate spatial resolution of 12.5 µm. We aimed to investigate morphologic changes in ductus arteriosus after long-term PGE1 infusion using XPCT. METHODS: Seventeen ductus arteriosus tissue samples from patients with hypoplastic left heart syndrome were obtained during the Norwood procedure. The median duration of lipo-prostaglandin E1 (lipo-PGE1) administration was 48 days (range, 3 to 123). Structural analysis of ductus arteriosus was performed and compared with conventional histologic analysis. RESULTS: The XPCT was successfully applied to quantitative measurements of ductal media. Significant correlation was found between the duration of lipo-PGE1 infusion and mass density of ductal media (R = 0.723, P = .001). The duration of lipo-PGE1 administration was positively correlated with elastic fiber staining (R = 0.799, P < .001) and negatively correlated with smooth muscle formation (R = -0.83, P < .001). No significant increase in intimal cushion formation was found after long-term lipo-PGE1 administration. Expression of ductus arteriosus dominant PGE2-receptor EP4 almost disappeared in specimens when lipo-PGE1 was administered over 3 days. CONCLUSIONS: Disorganized elastogenesis and little intimal cushion formation after long-term lipo-PGE1 administration suggest that ductus arteriosus remodeled to the elastic artery phenotype. Because EP4 was downregulated and ductus arteriosus exhibited elastic characteristics, the dosage of lipo-PGE1 might be decreased after a definite administration period.

Visualization and quantification of the atrioventricular conduction axis in hearts with ventricular septal defect using phase contrast computed tomography.

OBJECTIVE: To visualize and quantify the atrioventricular conduction axis in the setting of ventricular septal defect using phase contrast computed tomography. METHODS: We used the SPring-8 synchrotron radiation facility in Hyogo prefecture in Japan, processing and reconstructing the data with 3-dimensional software. RESULTS: We studied 8 hearts obtained from patients known to have had ventricular septal defects, aged from 6 to 150 days, with a median of 24.5 days. None of the individuals, however, had undergone corrective surgery. The penetrating bundle was found at a median of 1.43 mm from the septal crest, with a range of 0.99 to 1.54 mm. The distance to the nonbranching bundle to the right ventricular endocardium was 1.10 mm, with a range from 0.49 to 2.49 mm, to the origin of the left bundle branch was 2.46 mm, with a range from 1.7 to 3.18 mm, and to the origin of the right bundle branch was 2.34 mm, with a range from 0.50 to 2.59 mm. The median distance from the edge of the caudal limb of the septomarginal trabeculation to the right bundle branch was 1.04 mm, with a range from 0.81 to 1.16 mm. CONCLUSIONS: We were able to show the precise location of the axis, with our findings suggesting that longitudinal sutures placed along the posteroinferior rim should be effective in avoiding iatrogenic injury, but sutures should not be placed in the valley between the limbs of the septomarginal trabeculation.

Successful Truncal Valve Replacement With a Mechanical Valve After Bilateral Pulmonary Artery Banding.

Surgical management of truncus arteriosus, or common arterial trunk, has expanded over the past three decades to include earlier surgical intervention, initially during infancy and now chiefly in the neonatal period. Many studies have shown that preoperative truncal valve insufficiency is an independent risk factor for mortality. We herein present the case of a five-month-old boy with severe truncal valve insufficiency who underwent repair of common arterial trunk and prosthetic replacement of the truncal valve with associated annular enlargement after initial stabilization in the newborn period via palliative bilateral pulmonary artery banding. We believe that initial bilateral pulmonary artery banding represents a viable option for some cases of common arterial trunk involving truncal valve insufficiency.

Single-center experience of the bridge-to-bridge strategy using the Nipro paracorporeal ventricular assist device.

Currently, we use the Nipro paracorporeal VAD (p-VAD) for initial short-term ventricular support, as a bridge to decision (BTD) or a bridge to candidacy (BTC) treatment, in Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) levels 1 and 2 patients. However, it is possible that compared to patients with primary implantable-VADs (P-iVAD), the bridge-to-bridge (BTB) patients are more likely to develop complications. This retrospective study used data from 24 consecutive BTB patients who were initially implanted with Nipro p-VAD as BTD or BTC treatments between April 2011 and March 2016, and subsequently underwent conversion to an i-VAD. The data from 72 patients who underwent a primary i-VAD (P-iVAD) procedure were used for comparison. Between the two groups, there was no significant difference in the incidence of infectious events (p = 0.72) or stroke (p = 0.44). Orthotropic heart transplantation was performed in 6 of the 24 patients in the BTB group and in 21 of the 72 patients in the P-iVAD group. The 1- and 2-year survival rates were 95.8% and 95.8% in the BTB group and 91% and 85.8% in the P-iVAD group; these values were not significantly different between groups (p = 0.91). Based on these results we conclude that BTB using Nipro p-VAD is a reasonable strategy for treating patients with severe decompensated end-stage heart failure.

Novel driveline route for prevention from driveline infection: Triple tunnel method.

BACKGROUND: The most prevalent and serious infection related to left ventricular assist devices (LVADs) is driveline infection (DLI). From 2014, we employed a revised surgical technique (triple tunnel method), which deployed a longer subfascial driveline (DL) route. METHODS AND PATIENTS: We retrospectively analyzed 34 patients fitted with either of the two types of axial pumps: HeartMate II (n=23) and Jarvik 2000 (n=11). Prior to 2014, the DL proceeded from the pump pocket just above the posterior sheath of the rectus muscle toward a vertical skin incision at the right lateral border of the rectus muscle. Then, DL was turned leftward into the subcutaneous tissue to redirect its exit to the left side [subcutaneous tissue group (Group S): n=14]. From 2014, we made an additional skin incision below the umbilicus with the aim of lengthening the subfascial DL route [muscle group (Group M): n=20]. RESULTS: DLI occurred in 10 patients (71.4%) in Group S and in 1 patient (5%) in Group M (p<0.05, Chi-square test). The freedom rate from re-admission at 1 year due to DLI was 64% in Group S and 95% in Group M, respectively (p=0.021, log-rank test). Furthermore, logistic regression analysis revealed that DL route was significantly associated with DLI (odds ratio, 10.1; 95% confidence interval, 1.15-275.3). CONCLUSION: Although a longer follow-up period will be needed, the triple tunnel method may be beneficial in the prevention of DLI.

Sternal semi-closure using a bioresorbable osteosynthesis device: a new method for delayed sternal closure.

PURPOSE: To evaluate the safety and efficacy of our new delayed sternal closure (DSC) method, involving sternal semi-closure using a bioresorbable osteosynthesis device and complete skin closure. METHODS: Between 2013 and 2017, 36 patients underwent DCS at our hospital. The patients were divided into two groups based on the method used for DSC. The later conventional DSC group consisted of 18 patients undergoing late complete sternal closure following fixation of pulmonary and hemodynamic instability, and the new DSC group consisted of 18 patients undergoing early sternal semi-closure a few days after surgery. In the new DSC group, the sternum was fixed with Super Fixsorb MX40, followed by complete skin closure. RESULTS: Respiratory and hemodynamic conditions, such as systolic blood pressure, cardiac index, tidal volume, and regional oxygen saturation, were significantly more stable in the new DCS group than in the conventional DSC group. The hospital stay was also significantly shorter in the new DSC group. Although there were no serious complications, one patient from the new DCS group suffered deformity of the sternum, which was managed successfully. CONCLUSION: The sternal semi-closure method decreases pulmonary and cardiac instability during DSC, making early DSC possible.

Non-invasive measurement of cardiac output using AESCULON® mini after Fontan operation.

BACKGROUND: Electrical velocimetry correlates well with established methods of measuring cardiac output (CO) such as thermodilution and echocardiography. In this study, we compared the cardiac function of children with single right ventricle (SRV) and single left ventricle (SLV) on non-invasive postoperative measurement of hemodynamic parameters using AESCULON® mini. METHODS: Demographic, preoperative, and perioperative data were obtained from medical records. We retrospectively reviewed the AESCULON mini data of 21 patients with single ventricle who underwent Fontan operation. The patients were divided into two groups according to morphologic diagnosis: SRV (n = 9) and SLV (n = 12). The following hemodynamic parameters were analyzed: stroke volume (SV); CO; cardiac index (CI); stroke volume variation (SVV); and ventricular ejection time (VET). RESULTS: Hemodynamic parameters were as follows (SRV vs SLV): heart rate (HR), 140.5 beats/min versus 121 beats/min; SV, 14.5 mL vs 19.9 mL; CO, 2 L/min vs 2.3 L/min; CI, 4.3 L/min/m2 versus 4.4 L/min/m2 ; SVV, 15.5% versus 13.9%; and VET, 167.7 s versus 197.7 s. HR and VET were statistically different between the two groups. CONCLUSIONS: CI does not differ with laterality of the single ventricle. SRV VET, however, was significantly shorter than SLV VET in the acute postoperative period. Conversely, SRV HR was higher than SLV HR, which may mean that SRV compensates for lower VET by increasing HR.

Successful management of apical abscess after Nipro left ventricular assisted device explantation by removal of apical cuff and omentopexy.

Nipro-Toyobo-paracorporeal pulsatile flow VAD (Nipro VAD; Nipro, Osaka, Japan) has been used most commonly as a paracorporeal VAD (p-VAD) in Japan. There are few reports describing clinical course of post LVAD explantation and its complication. We herein present two cases of apical abscess after the explantation of the device. SSI is a main risk factor of formation of the apical abscess at the time of LVAD explantation. It is mandatory to perform sufficient debridement and closure of the layers including abdominal muscle and anterior abdominal fascia at exit sites in the explantation surgery. Omentopexy is also helpful for prevention from infection. Routine removal of apical cuff and outflow graft could be considered as one of the options when LVAD is explanted as bridge to recovery.

A successful management of infection of the left ventricular assist device by pump exchange: conversion from DuraHeart to Jarvik 2000.

We successfully controlled infection of a left ventricular assist device by performing pump exchange. A 53-year-old man was implanted with DuraHeart for ischemic cardiomyopathy as a bridge to transplantation. Two years later, he was hospitalized with the diagnosis of driveline infection. The blood cultures detected Pseudomonas aeruginosa. During the admission, he developed brain hemorrhage perhaps due to septic emboli. The chest computed tomography scan revealed a small defect inside the outflow graft of the DuraHeart, which was highly suspected of vegetation. He underwent pump exchange, from DuraHeart to Jarvik 2000 with concomitant omentopexy. His postoperative course was uneventful, and he was discharged with no sequela of the brain hemorrhage. Four months after the pump exchange, he successfully underwent heart transplantation. No infectious tissue was observed in the pericardial space at the time of heart transplantation. Pump exchange is an effective way to manage refractory left ventricular assist device infection, and the timing of surgical intervention is of great importance.

Randomized Study of a New Noninvasive Skin Closure Device for Use After Congenital Heart Operations.

BACKGROUND: We report a new, noninvasive Zip surgical skin closure device (ZipLine Medical, Campbell, CA). This device is considered to have good cosmetic outcomes after operations and reduces surgical time. In this study, skin closure using the Zip device was compared with subcuticular sutures and the usefulness and safety of this new device was evaluated. METHODS: This was a prospective, randomized study of 214 patients who underwent cardiac operations through a median sternotomy from June 2014 to December 2015. In 136 patients, this was a first operation group of which 71 patients underwent Zip surgical skin closure (Zip group), and 65 patients underwent subcuticular sutures (suture group). In 78 patients, this was a reoperation group, of which 42 patients were in the Zip group and 36 patients were in the suture group. Cosmetic results using the Vancouver Scar Scale were evaluated separately in the first operation group and reoperation group. RESULTS: There were significant differences in the total Vancouver Scar Scale score between the first operation group (p < 0.001) and reoperation group (p = 0.007). The skin closure time was significantly shorter in the Zip group than in the suture group (113.0 ± 9.1 seconds vs 375.9 ± 60.2 seconds, p < 0.001). No significant differences were found regarding the rate of surgical site infection between the groups. Complications peculiar to this device included skin discoloration (0.9%), epidermolysis (0.9%), and exfoliation of the device (1.8%); however, no serious complications developed. CONCLUSIONS: In congenital heart operations through a median sternotomy, the Zip surgical skin closure device was an excellent choice for improving the cosmetic appearance and reducing the wound closure time. In addition, it proved to be a device that could be used safely.

Two Cases of Ventriculocoronary Connection From the Left Ventricle in Hypoplastic Left Heart Syndrome.

Advanced surgical technique and comprehensive postoperative management have improved remarkably early and late outcomes of hypoplastic left heart syndrome. However, recent reports have focused on the poor outcome in a series of cases with mitral stenosis and aortic atresia subtype, and ventriculocoronary connections. We consider treatment strategies by reviewing 2 cases of ventriculocoronary connection, both of which had poor outcomes.

Surgical treatment of tetralogy of Fallot with absent pulmonary valve syndrome.

The patient was a 3-month-old girl weighting 3.6 kg, diagnosed with tetralogy of Fallot and absent pulmonary valve syndrome. We surgically repaired the tetralogy of Fallot by patch closure of the ventricular septal defect, right ventricular outflow tract reconstruction using an expanded polytetrafluoroethylene monocusp patch with a bulging sinus, and removal of the bronchial obstruction by anterior translocation of the pulmonary artery using the Lecompte maneuver.

Simple and Useful Method to Minimize Tracheal Compression Resulting From Concave Sternum During Congenital Heart Surgery.

A 12-month-old boy weighing 5.2 kg underwent surgical repair for a ventricular septal defect (VSD) combined with airway obstruction resulting from pectus excavatum. His right atrium and left main bronchus were extremely compressed by the sternum. To repair the VSD, we performed a sternal closure for pectus excavatum that used a mesh-shaped bioresorbable device (Super Fixsorb MX40; Takiron Co, Ltd, Osaka, Japan) made of hydroxyapatite/poly-L-lactide composites. After the operation, the cardiac and tracheal compression caused by the sternum was alleviated.

Rare combination of congenital heart disease and pulmonary alveolar proteinosis.

Here, we describe a case of total anomalous pulmonary venous return with coarctation of the aorta that was diagnosed as pulmonary alveolar proteinosis at autopsy in a male infant. Surgical repair was performed at 1 day of age, but the infant died on postoperative day 51 due to respiratory insufficiency without any evidence of pulmonary venous obstruction. He had been unexpectedly diagnosed with pulmonary alveolar proteinosis and pulmonary hypoplasia on autopsy. Congenital pulmonary alveolar proteinosis is a serious condition with a high mortality rate, which should be considered in the differential diagnosis in patients with a clinical picture of pulmonary venous obstruction, because most patients are unable to survive without proper treatment. In this report, we address specific issues that should be discussed in such cases based on our recent experience.

Fontan completion following flow adjustable bilateral pulmonary artery banding.

We have performed bilateral pulmonary artery banding operations combined with planned percutaneous balloon dilatation at banding sites for patients with hypoplastic left heart syndrome and related anomalies. Here, we report a case of Fontan completion in a patient who underwent aortic arch repair and a bidirectional Glenn procedure following flowadjustable bilateral pulmonary artery banding. The patient had a double-inlet left ventricle, a hypoplastic right ventricle, a hypoplastic aortic arch, and coarctation of the aorta. She underwent banding at 9 days of age and balloon dilatation at 2 months. The Damus-Kaye-Stansel anastomosis, aortic arch repair, and bidirectional Glenn procedure were performed at 5 months of age, and the extracardiac Fontan procedure was performed at 1.5 years.