The Impact of a Prior Norwood Procedure on Cardiac Transplantation in Failed Fontan Physiology

Objective:The objective of this study was to compare cardiac transplant operative and postoperative courses of patients with failed Fontan physiology who were initially palliated with a Norwood(FFN)to those without a prior Norwood(FF).Methods:A single-institution retrospective review of all patients with Fontan failure who under-went cardiac transplantation from 2003–2021 was completed-22 underwent prior Norwood(FFN)and 11 did not(FF).Descriptive and inferential statistics were calculated for operative course and patient outcomes.Results:The operative course of the FFN cohort appeared to be more complex(not statistically significant,but clinically relevant)-this group exclusively experienced sternal re-entry events(3 of 22 patients)and concomitant neo-aor-tic reconstruction(6 patients),had a longer duration of surgery(median of 682 min vs.575.5 min),more time on circulatory arrest(median of 25.5 min vs.12.5 min),and more frequent use of open sternal management[50%of patients(11/22)vs.27.3%of patients(3/11)].Postoperatively,these patients underwent more mediastinal explora-tions[other than sternal closure;40.9%of patients(9/22)vs.18.2%of patients(2/11)],spent more time on mechanical ventilation(median of 5 days vs.2 days),had a longer length of stay(median of 30 days vs.19 days),and required more catheter-based re-interventions[22.7%of patients(5/22)vs.9.1%of patients(1/11)].Conclu-sion:Although underpowered,our results suggest that the operative course of FFN patients is more challenging,based mostly on neo-aortic arch issues.In turn,this likely leads to a more complex postoperative course.We are currently collaborating with other institutions to increase the cohort size and power of the study.

Fontan循环的新时代——远期淋巴系统并发症研究进展

全腔静脉-肺动脉连接术(Fontan姑息手术)挽救了大量单心室结构患儿的生命。然而,术后远期淋巴系统并发症严重影响着患者的预后。现回顾既往相关文献,总结Fontan术后患者淋巴系统并发症的自然病程、病理生理、临床表现、诊断和治疗管理。

Fontan手术的微创化发展及研究进展

Fontan手术是目前功能性单心室患者的首选治疗方法,但传统手术多次开胸带来的众多并发症仍难以避免。随着介入技术的飞速发展,外科手术和介入手段混合使用的Hybrid Fontan手术开始被尝试用于替代分期外科手术以建立Fontan循环,为Fontan手术的微创化提供了新的可能。该文介绍Fontan手术微创化的发展过程、常见Hybrid Fontan手术方法及相关研究进展。

Fontan术后的抗凝管理策略及并发症的预防和治疗

Fontan手术是将静脉血流直接引入肺动脉,降低单一心室的容量负荷,提高体循环氧合浓度的一类手术方式的总称。该术式自开展以来经过多次改良被广泛用于治疗功能性单心室的复杂紫绀型先天性心脏病患儿。血栓栓塞是Fontan术后的重要并发症之一,也是影响患者远期预后的主要问题。Fontan患者术后血栓形成和栓塞的发生率高,临床危害大,但针对该情况的预防、检查及治疗策略等仍存在争议,尚未达成共识。本文将Fontan术后血栓栓塞并发症的成因、预防、检查及治疗策略作一综述,旨在为提高Fontan患者的远期生存质量提供治疗参考。

Comparison of 2D and 4D Flow MRI Measurements for Hemodynamic Evaluation of the Fontan Palliation

Background:The assessment of Fontan circuit’sflow is traditionally evaluated by multiple through-plane phase-contrast MRI acquisitions(2Dflow),while recently,a single volumetric 4D-flow MRI acquisition is emerging as a comprehensive tool for the hemodynamic evaluation in congenital heart diseases.Purpose:To compare 2D and 4D-flow MRI measurements in patients after Fontan palliation and to evaluate parameters affecting potential dis-agreement.Methods:39 patients after Fontan palliation(23 males,age 22±11 years)who underwent cardiac MRI with 2D and 4D-flow MRI acquisition were included in the study.In all patients,bloodflow quantification in the Fontan circuit and aorta by 2Dflow and by 4Dflow MRI acquisition blinding to the 2D results was per-formed.The agreement between 2D and 4D-flow MRI was calculated as the intraclass correlation coefficient(ICC).The mean absolute differences between 4D and 2Dflows were analyzed using linear regression models.Results:4D-flow MRI acquisition time was slightly lower than 2D(7.6±1.8 min vs.9.4±3.3 min,p=0.03).Flow was slightly predominant in the right pulmonary artery(58%of total pulmonaryflow).Conduit/tunnel-pul-monary arteriesflow accounted for 60%of the Fontan circuit.Agreement between 2D and 4D was overall good-to-excellent from ICC:0.81795%CI:0.637–0.907 to 0.93295%CI:0.866–0.965.There was no significant influ-ence of evaluated parameters on the agreement on 4D and 2Dflow.Conclusions:4D-flow MRI represents a valid tool in Fontan’sflow quantification.Further larger studies are needed to confirm our results and to evaluate the impact of advanced 4D-flow MRI parameters on the prognostic stratification in patients after Fontan palliation.

Ventricular Arrhythmia in the Fontan Circulation:Prevalence,Risk Factors and Clinical Implications

Objective:Sudden cardiac death(SCD)and malignant ventricular arrhythmia(VA)are increasingly recognized as important issues for people living with a Fontan circulation,but data are lacking.We sought to characterize the cohort who had sudden cardiac death,most likely related to VA and/or documented VA in the Australia and New Zealand Fontan Registry including risk factors and clinical outcomes.Methods:A retrospective cohort study was performed.Inclusion criteria were documented non-sustained ventricular tachycardia,sustained ventricular tachycardia,ventricular fibrillation,resuscitated cardiac arrest or SCD>30 days post-Fontan completion.Results:Of 1611 patients,20(1.2%)had VA;14(1.0%)had VA without SCD and 6(<1%)had SCD(6%of all deaths recorded in Registry;5 of those had documented VA at the time of arrest and 1 was presumed to be VA-associated).The median age at first VA was 20.5(14–32)years,10(50%)were females,and the median age at Fontan operation was 8(4–17)years.On univariable analysis,hypoplastic left heart syndrome(p=0.03)and older age Fontan operation(p<0.001)were associated with VA.Earlier Fontan era(p<0.003),atriopulmonary Fontan(p<0.001),pre-Fontan atrioventricular valve repair(p=0.013)pre-or post-Fontan atrial arrhythmia(p=0.010)were associated with SCD.Patients with VA had a 3 times higher risk of death or heart transplant(HR 3.27(1.19,8.98),p=0.02).Conclusions:A proportion of people living with a Fontan circulation have malignant VA.Routine VA screening in this cohort is essential.More data are needed to aid risk stratification.

Hemodynamic Profiling Using a Cardiac Index–Systemic Vascular Resistance Plot in Patients with Fontan Circulation

Background: Elevated Fontan pressure (FP) alone cannot fully predict clinical outcomes. We hypothesized thathemodynamic profiling using a cardiac index (CI)-systemic vascular resistance (SVR) plot could characterize clinicalfeatures and predict the prognosis of post-Fontan patients. Methods: We included post-Fontan patients whounderwent cardiac catheterization at age < 10 years. Patients were classified into four categories: A, CI ≥ 3, SVRindex (SVRI) ≥ 20;B, CI < 3, SVRI ≥ 20;C, CI ≥ 3, SVRI < 20;and D, CI < 3, SVRI < 20. The primary outcome wasfreedom from the combined endpoint: new onset of protein-losing enteropathy or plastic bronchitis, heart transplant,and death. Clinical and hemodynamic variables and freedom from the endpoint were compared betweenthe hemodynamic categories and outcome predictors were evaluated. Results: Eighty-three patients wereincluded. Median follow-up was 5.3 years. Category A/B/C/D consisted of 4/15/53/11 patients, respectively. Allthe patients in category A were New York Heart Association I/II and had a significantly lower pulmonary vascularresistance index (PVRI). Patients in category C had lower pulmonary/systemic blood flow. Patients in category Dhad a higher PVRI and had the poorest freedom from the endpoint (44% at 5 years). Elevated FP and category Dwere outcome predictors. Conclusions: CI-SVR plots was a novel adjunctive method for Fontan hemodynamicprofiling.

Minor Pressure Differences within the Fontan-Anastomosis in Patients with Total Cavopulmonary Connection by 4D-Flow Magnetic Resonance Imaging

Background: Pressure measurement in total cavopulmonary connection (TCPC) patients is a domain of cardiaccatheterization. 4D velocity encoded cardiovascular magnetic resonance (4D–flow MRI) offers an alternative forassessment of even minor pressure differences. The scope of this study was to measure even minor pressure differencesin the anastomosis of TCPC patients, who are clinically uncompromised. Methods: Twenty-four patients(median 15 years [8;34]) with TCPC were studied prospectively by 4D-flow MRI. Pressure differences betweensuperior vena cava (SVC) and extracardiac conduit (C) to both right pulmonary artery (RPA) and left pulmonaryartery (LPA) were assessed. Small fluid obstructions as vortices within the anastomosis were detected by flowpathlines from 4D-flow MRI. In two patients pressure differences were calculated also by computational flowdynamics (CFD) as a plausibility check for the order of magnitude. Results: Median values of pressure differencesin the anastomosis between SVC and RPA were 0.63 (0.21–2.1) mmHg, between C and RPA 0.67 (0.3–2.2)mmHg, between SVC and LPA 0.8 (0.3–2.4) mmHg and between C and LPA 0.7 (0.2–1.9) mmHg. Patients withpotential flow obstruction (stents, occluder, vortices) had significantly higher gradients at the anastomosis (p <0.05) than patients without potential obstructions, although the absolute values were small. CFD- and measurement-based pressure difference showed good agreement. Conclusion: 4D-flow MRI is able to detect minor pressuredifferences within the Fontan circuit even in patients with apparently satisfactory TCPC. Slightly higherpressure differences are due to the presence of small flow obstruction.

Preliminary Evaluation of Hemodynamic Effects of Fontan Palliation on Renal Artery Using Computational Fluid Dynamics

Background:The assessment of renal function is important to the prognosis of patients needing Fontan palliation due to the reconstructed compromised circulation.To know the relationship between the kidney perfusion and hemodynamic characteristics during surgical design could reduce the risk of acute kidney injury(AKI)and the postoperative complications.However,the issue is still unsolved because the current clinical evaluation methods are unable to predict the hemodynamic changes in renal artery(RA).Methods:We reconstructed a three-dimensional(3D)vascular model of a patient requiring Fontan palliation.The technique of computational fluid dynamics(CFD)was utilized to explore the changes of RA hemodynamics under different possible blood flow rates.The relationship between the kidney perfusion and hemodynamic characteristics was investigated.Results:The calculated results indicated the declined tendency of the pressure and pressure drop as the flow rate decreased.When the flow rate decreased to two-thirds of its baseline,both the pressure of left renal artery(LRA)and the pressure of right renal artery(RRA)dipped below 50%,and the pressure of RRA fell more quickly than that of LRA.Uneven distribution of WSS was observed on the trunk of RA,and the lowest WSS was found at the distal of RA.The average WSS in RA dropped to around 50%as the flow rate reached one-third of its baseline.Conclusions:As a promising approach,CFD can be utilized to quantitatively evaluate the hemodynamic characteristics of RA and contribute to offsetting the drawbacks of clinical assessments of renal function,to help realize better prognosis for the patients with Fontan palliation.

改良Fontan手术治疗复杂先天性心脏病

目的 总结改良Fontan手术治疗复杂先天性心脏病的临床经验.方法 1996年11月～2005年5月,采用改良Fontan手术纠治124例复杂先天性心脏病（病种包括三尖瓣闭锁、单心室、右心室双出口、大动脉错位、肺动脉闭锁、矫正型大动脉转位、右心室发育不良等）患者,手术年龄7.6±5.5岁.常温非体外循环下手术19例,体外循环下手术105例.右心房-肺动脉连接17例,右心房-右心室连接19例,全腔静脉-肺动脉连接术（TCPC）88例.23例行分期手术.结果 术后早期（术后30d）死亡17例（13.7%）,其中行右心房-肺动脉连接者死亡率为23.5%（4/17）,行右心房-右心室连接者死亡率为 15.8%（3/19）,行TCPC者死亡率为11.4%（10/88）,同期预留或术后开窗手术死亡率为14.6%（6/41）,分期手术患者死亡率为 8.7%（2/23）.死亡原因：低心排血量、多器官功能衰竭和心室颤动等.术后早期并发症发生率为16.9%（21/124）,主要为胸腔积液、心律失常、心包积液和低心排血量综合征等.术后随访89例,随访时间6～65个月.远期再住院率6.5%,再手术率0.9%.3例出现再发性胸腔积液,3例出现心包积液,1例出现下腔静脉梗阻,均经相应的治疗后治愈.其余患者心功能恢复好.结论 改良Fontan手术是治疗复杂先天性心脏病中功能性单心室的最佳手术方案;房间隔开窗可明显提高术后早期疗效,减少渗出.

应用系列改良Fontan手术治疗复杂先天性心脏病

目的探讨系列改良Fontan手术的特点和治疗复杂先天性心脏病的效果,进一步提高对其临床应用的认识。方法回顾性分析1992年9月～2006年6月期间77例复杂先天性心脏病患者行改良Fontan手术治疗的临床资料,其中行右心房-肺动脉吻合术21例,心房内板障或管道全腔静脉-肺动脉连接术28例,心外人工管道全腔静脉-肺动脉连接术24例,自体右房壁管道全腔静脉-肺动脉连接术2例,自体带蒂心包心外管道全腔静脉-肺动脉连接术1例,主肺动脉与下腔静脉吻合全腔静脉-肺动脉连接术1例。结果术后早期死亡5例,其中死于心力衰竭3例,突发心律失常1例,脑出血1例。再次手术1例,术后早期生存率93.5%(72/77),手术成功率92.0%。左心室舒张期末内径(LVEDD)较术前减小(52.5±7.8mmvs.62.5±11.0mm,P=0.013),左心室射血分数(LVEF)较术前增加(68.5%±4.0%vs.62.0%±4.5%,P=0.032)。随访63例,随访率87.5%(63/72),随访时间1～15年。随访期间死亡4例,远期再次手术1例,远期生存率88.3%,手术成功率86.0%。结论在复杂先天性心脏病的治疗中,改良Fontan手术有良好的疗效;同时根据具体解剖结构可选择不同的手术方式。

二期Fontan术术前HGB、HCT和SpO_2与肺血管阻力的相关性

目的分析二期Fontan术术前肺血管阻力(PVR)与血红蛋白浓度(HGB)、红细胞比容(HCT)及经皮氧饱和度(SpO2)的关系,建立无创评价PVR的方法。方法选择35例准备施行二期Fontan手术的患儿,测定静脉血HGB、HCT和安静时不吸氧状态下的SpO2,同时行心导管检查,测定和计算PVR。分别将HGB、HCT和SpO2作为自变量,PVR作为因变量,进行直线相关分析,并分别计算HGB、HCT和SpO2与PVR的直线回归方程。结果35例患儿术前HGB和HCT与SpO2均呈显著的负相关(r=-0.685,P<0.01;r=-0.634,P<0.01);HGB、HCT和SpO2与PVR也存在显著的相关性(r=0.562,P<0.01;r=0.579,P<0.01;r=-0.392,P<0.05)。HGB、HCT和SpO2与PVR的直线回归方程分别为y=0.268x-2.093,y=0.108x-2.976和y=11.951-0.117x。结论二期Fontan术术前HGB、HCT和SpO2与PVR均高度相关,可根据计算的直线回归方程,由术前测得的HGB、HCT和SpO2值计算PVR估计值,用以评价肺血管阻力。

心外管道Fontan手术治疗复杂先天性心脏病

目的探讨心外管道Fontan手术方法治疗小儿复杂先天性心脏病的早期效果。方法9例复杂性先天性心脏病，男5例．女4例，年龄3～9岁。其中单心室5例，三尖瓣闭缩、右室双出口各2例。均在体外循环心脏不停跳下行心外管道Fontan手术。结果全组患儿无死亡，经皮血氧饱和度〉95％，无心律失常．但均有明显胸腔积液表现。

改良侧通道Fontan手术在小儿复杂先天性心脏病中的应用

目的总结改良侧通道Fontan手术纠治小儿危重复杂先天性心脏病的经验,探讨该手术方法的优越性。方法自1999年3月至2008年8月我院共对86例复杂型心内畸形患者施行心内板障侧通道Fontan手术,男47例,女39例;年龄1.9～11.5岁,平均年龄4.7岁;体重8.6～52.0kg,平均体重17.0kg。病种为无脾综合征33例,多脾综合征17例,三尖瓣闭锁(TA)11例,房室连接不一致的右心室双出口(DORV)11例,完全性大动脉错位(D-TGA)合并肺动脉狭窄8例,矫正性大动脉错位(cTGA)5例,Ebstein’畸形1例。术前分别行单侧双向上腔静脉肺动脉吻合术(BSCPA),双侧双向上腔静脉肺动脉吻合术和半-Fontan手术(hemi-Fontan opertiong);二次手术时间间隔0.7～7.8年(3.6±2.9年)。术中采用心内板障侧通道Fontan手术(LT组,47例)和改良心内板障侧通道Fontan手术(M-LT组,39例)方法连接下腔静脉的血引流入右肺动脉,部分完成二期改良Fontan手术。结果两组共死亡7例(9%),LT组死亡5例,M-LT组死亡2例,差异无统计学意义(χ2=0.865,P=0.448)。在分期改良Fontan手术中,M-LT组患者术前行BSCPA术明显多于LT组。术后仍有22例患者发生低心排血量综合征,其中肾功能受损导致无尿而行腹膜透析13例,透析2～5d后尿量恢复。术后LT组的心律失常患者明显多于M-LT组(χ2=8.763,P=0.003),置胸腔引流管时间LT组明显长于M-LT组(t=2.970,P=0.003)。门诊随访3个月～8年,无1例死亡。M-LT组随访33例(85%),LT组随访39例(83%),均未出现严重的并发症,患者活动能力明显改善。结论改良侧通道Fontan手术有一定的优越性,不失为一种提高手术成功率、减少术后并发症的改良方法。

肝静脉直接入心房的(功能)单心室患者的改良Fontan术式及早中期疗效

目的:总结肝静脉直接入心房(SHV)的(功能)单心室患者的改良Fontan术式及早中期临床结果。方法:回顾性分析2009-01至2015-12阜外医院对39例SHV的(功能)单心室患者施行改良Fontan术的临床资料。男26例(66.7%),平均年龄(6.98±3.62)岁,平均体重(20.79±9.66)kg,术前平均肺动脉压(m PAP)9.77±2.51(4~15)mm Hg(1mm Hg=0.133k Pa)。依据SHV患者是否合并下腔静脉与心尖同侧(ACJ),分为SHV组(n=29)和SHV+ACJ组(n=10)。对术后早期(术后3个月)及中期(5年)进行临床结果分析。结果 :两组患儿的临床资料比较差异无统计学意义(P>0.05)。39例患者中,一期手术20例,二期手术19例(18例为Glenn术后,1例为B-T术后)。选择的改良Fontan术式主要采取外管道—共同开口术式(30例,76.9%)。19例患者建立体外循环并阻断主动脉,体外转流时间72~446 min,平均(189.74±84.96)min,主动脉阻断26~171min,平均(89.05±43.96)min;另19例患儿并行循环,体外转流时间60~209 min,平均(109.99±98.86)min。术后早期因并发症再次手术10例。术后院内死亡3例,死亡率7.7%。36例患儿平均随访时间3.90(0.83~7.17)年,35例心功能为Ⅰ级,1例为Ⅱ级,5年生存率100%。结论 :SHV的(功能)单心室患者行改良Fontan术后早中期随访结果良好。而改良Fontan术式的选择应依据下腔静脉与肝静脉间的距离以及是否合并ACJ。

Fontan手术后儿童的血栓弹力图

Fontan手术（Fontan procedure）是治疗复杂先天性心脏病的重要术式，主要用于功能性单心室。Fontan手术几经改良，目前主要应用的是全腔肺动脉连接术。栓塞是Fontan手术后重要的并发症之一，发生率达3％～33％，因此，Fontan手术后患者常被冠以“高凝血症”[1]。血栓弹力图（thmmboelastography，TEG）能反映凝血过程全貌[2]。本研究对Fontan手术后的儿童做血栓弹力图检测，以期发现Fontan手术后儿童血栓弹力图的规律。

先天性心脏病患儿Fontan手术围术期抗肝素血小板因子4抗体的变化及其影响因素

目的研究先天性心脏病（先心病）患儿Fontan手术围术期抗肝素血小板因子4（PF4）抗体的变化规律及其影响因素。方法随机选取Fontan手术患儿98例，美国麻醉医师学会（ASA）分级Ⅱ-Ⅲ级。所有患儿于开胸手术前、术后第5、10天分别采集股静脉血1ml，应用双抗原夹心法测定标本中人血小板第4因子IgG抗体水平。分别在术前和术后第1、3、5、7、10天检测患儿血小板计数。结果术后第5天Fontan手术患儿存活93例，抗肝素PF4抗体IgG阳性率为33．3％（31例）；术后第10天Fontan手术患儿存活91例，抗体IgG阳性率为41．8％（38例）。98例先心病患儿中有4例（4．1％）发生肝素诱导性血小板减少症，其中肝素诱导性血小板减少症伴血栓形成3例。结论先心病Fontan手术患儿因手术次数和术前心导管检查等因素增加与肝素接触的机会，会影响术后抗肝素PF4抗体IgG血清转化率。

Glenn术、Fontan术及改良Fontan术

改良 Fontan手术是近 30年来外科治疗复杂性先天性心脏病常用的一种手术方法 ,本文对改良 Fontan手术进行了较全面的综述 ,旨在系统地介绍这一复杂的心外科手术的血流动力学基础、手术设计及其演变的过程 ,使读者对这种高难度手术的不同术式、手术指征。