Lower bone strength in young patients with Fontan circulation compared to controls.

OBJECTIVES: Previous reports indicate bone deficits in patients with Fontan circulation. However, the consequences of these deficits on bone strength and when these changes occur are unclear. AIM: To compare the tibial bone strength-strain index between young patients (6-19 years) with Fontan circulation and age- and sex-matched controls, and to determine strength-strain-index in subgroups of children (6-12 years) and adolescents (13-19 years) versus controls. METHOD: The tibia was examined with peripheral quantitative CT. Based on the assessed data, bone strength-strain index was calculated in the lateral and anterior-posterior directions. RESULTS: Twenty patients with Fontan and twenty controls (mean age 13.0 ± 4.4 years; 50% females) were examined. Patients had a lower strength-strain index in the lateral direction compared to controls (808.4 ± 416.8mm3 versus 1162.5 ± 552.1mm3, p = 0.043). Subgroup analyses showed no differences regarding strength-strain index in children (6-12 years) with Fontan circulation compared to controls. However, the adolescents (13-19 years) with Fontan circulation had lower strength-strain indexes in both the lateral and anterior-posterior directions compared to controls (1041.4 ± 299.8mm3 versus 1596.4 ± 239.6mm3, p < 0.001, and 771.7 ± 192.4mm3 versus 1084.9 ± 215.0mm3, p = 0.004). When adjusted for height, there were differences between patients (6-19 years) and controls in strength-strain indexes in both the lateral and anterior-posterior directions. In subgroup analyses, the results remained robust. CONCLUSION: Young patients (6-19 years) with Fontan circulation have a lower strength-strain index in the tibia compared to controls. Subgroup analyses show that this deficit is mainly driven by the differences in adolescents (13-19 years), which might suggest that bone strength decreases with age.

Acute Kidney Injury and Mid-term Outcomes After Extra-Cardiac Fontan Conversion.

The aim of this study was to investigate the association of postoperative acute kidney injury and unplanned re-admission rate due to heart failure at 2 years follow-up in patients who had extra-cardiac Fontan conversion. This was a retrospective single-center study of patients who underwent conversion from classic Fontan to extra-cardiac Fontan between January 2014 and December 2021. Acute kidney injury was defined using the Kidney Disease Improving Global Outcomes criteria. A total of 47 patients underwent Fontan conversion. Acute kidney injury occurred in 22 patients (46.8%) and 5 patients with acute kidney injury needed renal replacement therapy. Unplanned re-admission rate at 2-year follow-up was significantly higher in patients with acute kidney injury even when renal function returned to baseline (8 [36.4%] vs. 3 [12.0%], p = 0.026 by the log-rank test). In conclusion, postoperative acute kidney injury after extra-cardiac Fontan conversion was associated with unplanned re-admission due to heart failure at 2-year follow-up even though renal function was recovered.

Effects of intravenous treprostinil in high-risk patients after total cavo-pulmonary connection / 中国胸心血管外科临床杂志

@#Objective     To explore the effects of intravenous treprostinil in different doses on the hemodynamics and postoperative outcomes after high-risk total cavo-pulmonary connection (TCPC). Methods    From 2018 to 2021, among 189 patients who underwent TCPC in the Department of Pediatric Cardiac Surgery of Fuwai Hospital, 26 high-risk patients who received the intravenous treprostinil therapy were retrospectively analyzed. There were 12 males and 14 females, with an age of 4 (3, 6) years and a weight of 17.6±6.2 kg. The patients were divided into two groups: a high-dose group [15 patients, maintaining dose>10 ng/(kg·min)] and a low-dose group [11 patients, maintaining dose≤ 10 ng/(kg·min)]. The hemodynamics before treprostinil using and during the first 24 hours after reaching the maintaining dose of treprostinil, and postoperative outcomes of the two groups were investigated. Results    The incidence of heterotaxia was higher in the high-dose group (66.7% vs. 18.2%, P=0.021). During the observation period, the mean pulmonary artery pressure decreased from 11.9±3.6 mm Hg to 11.0±3.3 mm Hg in the low-dose group (P=0.013), and from 12.9±4.7 mm Hg to 10.2±3.4 mm Hg in the high-dose group (P=0.001). The decreasing effect in the high-dose group was better than that in the low-dose group (P=0.010). There was no statistical difference in the postoperative outcomes between the two groups (P>0.05). In terms of side effects, patients needed temporarily increased dosage of vasoactive drugs to maintain stable blood pressure during 6-12 h after treprostinil therapy in the high-dose group. Conclusion    In patients after high-risk TCPC, intravenous high-dose treprostinil has a better therapeutic effect on reducing pulmonary artery pressure. However, it should be noted that increased dosage of vasoactive agents may be required to maintain blood pressure stability in patients with high-dose treprostinil.

Uni-ventricular palliation vs. bi-ventricular repair: differential inflammatory response.

BACKGROUND: To examine whether uni-ventricular palliation (UVP) and bi-ventricular repair (BVR) result in a different pattern of systemic inflammatory response to pediatric cardiac surgery with extra-corporeal circulation (ECC). METHODS: In 20 children (median age 39.5 months) undergoing either UVP (n = 12) or BVR (n = 8), plasma levels of the inflammatory cytokines TNF-α, IL-6, IL-10, and IL-12 and of procalcitonin (PCT), were measured before, during and after open cardiac surgery up to postoperative day (POD) 10. RESULTS: Epidemiologic, operative- and outcome variables were similar in both groups but post-operative central venous pressure that was higher in UVP. In the whole cohort, the inflammatory response was characterized by an early important, significant and parallel increase of IL-6 and IL-10 that reached their peak values either at the end of ECC (IL-10) or 4 h postoperatively (IL-6), respectively and by a significant and parallel decrease of TNF-α and IL-12 levels after connection to ECC, followed by a bi-phasic significant increase with a first peak 4 h after ECC and a second at POD 10, respectively. Patients after UVP showed a shift of the cytokine balance with lower IL-6- (p = 0.01) after connection to ECC, lower early post-operative TNF-α - (p = 0.02) and IL-12- (p = 0.04) concentrations and lower TNF-α/IL-10-ratio (p = 0.03) as compared with patients with BVR. Levels of PCT were similar in both groups. CONCLUSIONS: UVP is associated with an anti-inflammatory shift of the inflammatory response to cardiac surgery that might be related to the particular hemodynamic situation of patients with UVP.

Bovine jugular vein valved xenograft for extracardiac total cavo-pulmonary connection: The risk of thrombosis and the potential liver protection effect.

BACKGROUND: Currently, non-valved conduits are preferred for extracardiac total cavo-pulmonary connection (TCPC). However, previous work has failed to provide objective data comparing the postoperative outcome between non-valved TCPCs and bovine jugular vein valved xenograft (BJV) TCPCs. Hence, the objective of this study is to compare the postoperative outcomes in extracardiac TCPC patients who received BJV vs synthetic non-valved conduits and evaluate the effect of BJV on liver fibrosis. METHODS: Of 206 patients who had extracardiac TCPC from 2002 to 2017 were divided into three groups. Group A (n = 66) received BJV, group B (n = 37) received PET conduits and group C (n = 103) received polytetrafluoroethylene (PTFE) tube. Study endpoints were hospital outcomes, conduits thrombosis, reinterventions, and survival. Liver stiffness and fibrosis were assessed in eight patients with BJV. RESULTS: Preoperative parameters were comparable among groups. Thrombosis was significantly lower in group C (P < .0003) but no difference between groups A and B (P = .951). Reinterventions did not differ significantly among groups (Log-rank P = .598). Hospital deaths occurred in seven patients (3.4%). There was no difference in survival between groups (Log-rank P = .221). The median liver stiffness score was 18.65 kPa and the eight patients had advanced liver fibrosis (grade F3-4) in group A. CONCLUSION: PTFE is the recommended conduit for TCPC with a lower risk of thrombosis compared to BJV and PET. BJV conduits in TCPC circuits may not protect against liver fibrosis. BJV should not be considered as an option for TCPC.

Impact of rhBNP infusion on early postoperative recovery after total cavo-pulmonary connection surgery / 中华胸心血管外科杂志

Objective To compare the effects of rhBNP on the discharge time and pleural effusion in children with total cavo-pulmonary connection, and to provide a more reasonable method for the clinical treatment of postoperative children. Meth-ods Retrospective analysis of Jan 2016 to Jan 2017 during the hospital 40 cases of complex congenital heart disease in children with total cavo-pulmonary connection clinical data, of which 5 cases due to postoperative thrombosis or postoperative venous pressure was too high and had a second Fontan surgery, the patients excluded from the inclusion criteria. 9 cases of children re-turned to the ward after surgery, such as cardiac, diuretic and other conventional treatment based on the application of unequal dose of rhBNP(3-11 days) for the rhBNP group, 26 cases of conventional treatment of children with conventional treatment group. By comparing the early postoperative survival rate, the number of days of hospital stay and the retention time of the tho-racic drainage between the two groups. Results There were no significant differences in the time of cardiopulmonary bypass, postoperative ventilator use time, ICU time and positive inotropic drug scores in all the two groups. All the patients underwent preoperative examination with total cavo-pulmonary connection were alive and healthy discharge. The median hospital stay was 18 days in the rhBNP group(11-33 days, mean 19. 2 days), and the median length of hospital stay was 28 days in the routine treatment group(9 to 95 days, mean 34. 4 days). The difference of hospitalization days between the two groups was statistically significant(P=0. 038). In the retention time of the thoracic drainage tube, the median thoracic drainage tube retention time was 14 days(9-27 days, mean 15. 6 days) in the rhBNP group and 23 days in the conventional treatment group(7-91 days, mean 30. 9(P=0. 046). All the patients had no adverse effects such as excessive fluid load, intractable hypotension and liver or kidney function injury. Conclusion RhBNP can be used safely in pediatric cardiac surgery. Compared with the convention-al treatment group, rhBNP has advantages in the early discharge time and the time of thoracic drainage tube removal in children with total cavo-pulmonary connection.

What range of extra-cardiac conduit flow velocity is detectable intraoperatively following the completion of a total cavo-pulmonary connection?

BACKGROUND: Very few studies have investigated the blood flow velocity from the inferior vena cava (IVC) to the pulmonary artery following the Fontan operation using an extra-cardiac conduit (ECC). No studies at all have investigated the velocity immediately after the circulation is established. The purpose of this retrospective study was to find an acceptable flow velocity at the ECC following the completion of a total cavo-pulmonary connection (TCPC) via transesophageal echocardiography. FINDINGS: We measured the mean velocity (m-V) of the blood flow proximal to the anastomosis between the IVC and ECC in eight patients and compared the results with theoretically predicted values based on assumptions regarding the cardiac output, the ratio of the IVC flow to the superior vena cava flow, and the cross-sectional form of the ECC. Mean velocities ranging from about 15 to 60 cm/s were detected in the absence of any observable stenosis. The measured m-V was significantly faster than the predicted value in our study, both collectively and in every patient individually. The shrinking and compression of the ECC might account for the faster velocities measured in our cases. CONCLUSION: The observed range of m-V at the ECC, about 15-60cm/s, may be acceptable for the establishment of TCPC circulation.

Fontan Operation: Indications, Short and Long Term Outcomes.

Fontan operation, since its original description, has undergone a number of modifications so that it is now a staged, total cavo-pulmonary connection with fenestration. Stage I is palliation, depending upon the pathophysiology of the defect complex in early life, Stage II is bidirectional Glenn at about the age of 6 mo and Stage III is transfer of inferior vena caval blood to the pulmonary circuit along with fenestration between 2 to 4 y. Any patient that has only one functioning ventricle is a candidate for Fontan surgery. The morbidity and mortality have remarkably improved since the institution of staged, total cavo-pulmonary connection with fenestration. Complications during follow up continue to occur, though diminished with the newer modifications, and should be promptly addressed.

Successful radiofrequency catheter ablation of sinoatrial nodal reentrant tachycardia after a total cavo-pulmonary connection procedure with an extra-cardiac conduit.

We report a tachyarrhythmia case of a 32-year-old female with a single ventricle and heterotaxy syndrome. She had surgery involving a total cavo-pulmonary connection procedure using an extra-cardiac conduit (EC) at the age of 17 years. A tachycardia was repetitively induced with single atrial extrastimuli. An activation map was created revealing a centrifugal propagation pattern from the high atrial wall adjacent to the EC. At that site, a structure resembling the crista terminalis was recognized with intracardiac echocardiography. Therefore, high output energy was required to eliminate the tachycardia. It was thought to be a sinoatrial nodal reentrant tachycardia. .

Medico-Surgical Cooperative Treatment of Pulmonary Atresia with Intact Ventricular Septum

PURPOSE: The actual clinical examples of co-appliance of catheter intervention with surgical procedures in the treatment of pulmonary atresia with an intact ventricular septum(PA/IVS) which we have experienced in our institution are here shown, and the anatomical and hemodynamical profiles between each method is compared. METHODS: Medical records of 33 patients with PA/IVS who underwent various treatment from January, 1995 to December, 2000 were reviewed for a retrograde study. RESULTS: In three out of 10 patients who underwent percutaneous balloon pulmonary valvotomy (PPV), residual pulmonary stenosis were observed in their out patient department(OPD) follow-ups, eventually necessitatig balloon pulmonary valvuloplasty(BPV). One out of three patients exhibited deterioration of tricuspid regurgitation after BPV, requiring surgical tricuspid annuloplasty(TAP). Two out of the seven patients who received primarily surgical right ventricle outlet tract(RVOT) repair without any systemic-pulmonary shunt or intervention needed additional intervention employing cardiac catheterization after operation. Two patients received interventional catheterization before surgical RVOT repair. In five out of 11 cases of Fontan type operation, coil embolization of collateral circulation was done before total cavo-pulmonary connection(TCPC), and in three cases, interventional catheterization was needed after TCPC. CONCLUSION: Both medical and surgical treatment modalities are widely used in management of PA/IVS patients, and recent results prove that medico-surgical cooperative treatment is essential.

Conversion of Total Atrio-pulmonary Connection to Total Cavo-pulmonary Connection-Review of Indications and Hemodynamic Characteristics-

PURPOSE: Since the successful application of total atrio-pulmonary connection(TAPC) to patients with various types of physiologic single ventricles in 1971, post-operative survival rates have reached more than 90%. However some patients have been shown to present with late complications such as right atrial thrombosis, atrial fibrillation and protein losing enteropathy eventually leading to re-operation to control the long-term complications. The aim of this study is to review the results of total cavo-pulmonary connection(TCPC) in cases with late complications after TAPC. METHODS: Between Jan. 1995 and Dec. 2000, 6 patients(5 males and 1 female) underwent cardiac catheterization 11+/-3 months after conversion of previous TAPC to TCPC. We compared the hemodynamic and morphologic parameters before and after TCPC and also assessed the clinical outcomes. The indications for TAPC were tricuspid atresia in 4 cases and complex double-outlet right ventricle with single ventricle physiology in 2 cases. RESULTS: There was no peri-operative mortality and all patients were clinically and hemodynamically improved at a mean follow-up of 11 months(range: 4 to 13). However, protein losing enteropathy recurred in 2 patients; this was were successfully treated with subcutaneous administration of heparin. Right atrial pressure before TCPC was 18.0+/-3.6 mmHg, but baffle pressure, corresponding to right atrial pressure decreased to 14.8+/-3.6 mmHg after TCPC. The size of the pulmonary arteries did not regress after TCPC. CONCLUSION: The conversion of TAPC to TCPC improves clinical and hemodynamic status by decreasing the right atrial pressure and by providing a laminar cavo-pulmonary flow which enhances the effective pulmonary circulation in the so-called Fontan circulation.