Aplasia of semilunar valve leaflets: Two case reports and developmental aspects

Summary Two fetuses of approximately 11 weeks development with aplasia of the pulmonary as well as the aortic valve leaflets are reported. Both cases showed additional cardiac malformations. Case 1, with all leaflets missing, also had double-outlet right ventricle, hypplastic left ventricle, large ventricular septal defect, straddling tricuspid valve, and atretic mitral valve. Case 2, with only one hypoplastic aortic valve leaflet, showed hypoplasia of the mitral valve and the left ventricle, and a subaortic ventricular septal defect.The observations made and data in the literature suggest that aplasia of semilunar valve leaflets reflects an underdevelopment of the endocardial cushion swellings at the ventriculoarterial junction, rather than resulting primarily from a malseptation of the cardiac outflow tract.     

自体心包修复儿童主动脉瓣狭窄9例病例系列报告

目的：总结并分析以自体心包修复儿童先天性主动脉瓣狭窄的手术方法和早期预后。方法：纳入2013年7月至2015年6月在复旦大学附属儿科医院行自体心包主动脉瓣成形术的先天性主动脉瓣狭窄患儿,收集患儿的一般资料,围手术期情况,并发症,术前、术中、术后和随访时的超声心动图资料。结果：符合本文纳入标准的9例患儿进入本文分析,男6例,女3例,年龄4月龄至9岁。术前超声提示,三叶式和二叶式主动脉瓣分别为3例和6例;重度狭窄6例,中度狭窄1例,重度狭窄伴中度返流2例。9例均以自体心包再造或扩大主动脉瓣瓣叶。术后即刻与术前超声心动图比较：主动脉瓣最大跨瓣压差［（31.6±9.4）mm Hg vs（73.0±22.2）mm Hg, P=0.000］和主动脉瓣平均跨瓣压差［（15.8±18.3）mmHg vs （35.8±18.3）mmHg, P= 0.004］均下降。术后随访24～48（32±8）月,无死亡和再干预病例,未见严重不良事件,未见主动脉瓣重度狭窄或重度反流、升主动脉狭窄或扩张、主动脉瓣瓣环狭窄与扩张、瓣膜脱垂或瓣膜赘生物病例;3例患儿分别在随访18、24和12个月时出现瓣叶活动僵硬,瓣叶开放不完全。术后左室后壁厚径均呈下降趋势;末次随访时,8例患儿左室后壁厚径Z值（Z-LVPWd）均下降至正常水平（＜2）。结论：以自体心包修复主动脉瓣可改善先天性主动脉瓣狭窄患儿的血流动力学,手术风险低,术后早期疗效可,避免或延缓儿童主动脉瓣置换术,减少施行ROSS手术机会。     

Echocardiogram in mitral-aortic atresia: False identification of the ventricular septum and left ventricle

Summary M-mode echocardiograms were correlated with cardiac anatomy in six newborn infants who had autopsy-confirmed mitral-aortic atresia. Echoes from the mitral valve or the aortic valve were not identified. An echo resembling that from the ventricular septum was recorded posterior to the tricuspid valve in all six infants. This echo was separated from the posterior ventricular wall echo by a space that varied in width from 3 to 8 mm. In two infants, the echo was continuous with that from the posterior aspect of the aortic root area and in all six infants displayed an anterior systolic motion pattern. Autopsy demonstrated that in every case the left ventricle was minute and was located superiorly in the wall of the right ventricle; in life, the transducer beam would not have traversed the left ventricle. The right ventricle was enlarged in every case and had prominent trabeculations of the septal band that created large anatomic spaces within the right ventricle. This study suggests that echoes previously thought to represent the left ventricle and ventricular septum in infants with mitral-aortic atresia do not represent these structures and are possibly created by the unusual right ventricular anatomy. Recognition of this false-positive finding may be useful in the interpretation of echocardiograms of other lesions in which there are abnormalities of the aortic or mitral valve, especially if there is a dominant right ventricle. Supported by grant HL-07605 from the National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland     

儿童先天性主动脉瓣畸形32例病理组织学特征

目的 探讨儿童先天性主动脉瓣畸形的病理组织学特征，为诊断提供依据。方法 对2003年1月至2005年12月因先天性主动脉瓣畸形、主动脉瓣功能障碍行外科手术切除的32例儿童主动脉瓣标本进行大体观察和组织学检查，复习病史并摘录相关资料，分析其病理组织学特征。诊断依据临床表现、术前超声心动图、术中所见及术后病理组织学检查，除外风湿性或退行性主动脉瓣病变、感染性心内膜炎及原发性结缔组织病变如Marfan综合征。结果 32例儿童先天性主动脉瓣畸形中，男性27例，女性5例，男：女=5.4：1，年龄6~18岁，平均年龄14.9岁。二叶型占37.5％（12例），三叶型59.4％（19例），四叶型3.1％（1例）。主动脉瓣狭窄（aortic stenosis，AS）5例（15.62%），主动脉瓣关闭不全（aortic insufficiency，AI）25例（78.13%），AS-AI 2例（6.25%），均不伴其他心脏瓣膜病变。20例伴其他先天性心脏病：室间隔缺损19例，动脉导管未闭2例，右室双腔心1例，主动脉右冠窦瘤3例。病理组织学改变为瓣叶增厚、大小不等、不规则（卷曲或脱垂）及坚度增加，部分伴钙化，光镜下示纤维组织增生，粘液样变性，胶原纤维溶解、断裂，弹性纤维破坏，偶见胶原纤维玻璃样变性、灶性钙化，无小血管增生及炎性细胞浸润。少数可见心内膜面局部破溃，内皮下毛细血管增生，纤维素性渗出，炎性细胞浸润，继发性钙质、脂质沉着和纤维化。结论 儿童先天性主动脉瓣畸形以男性为多见，二叶型、三叶型主动脉瓣常见，常伴有其他先天性心脏病，瓣膜功能障碍以AI为主，病理组织学改变主要为为瓣叶增厚、大小不等、不规则（卷曲或脱垂），光镜下示纤维组织增生，粘液样变性，胶原纤维溶解、断裂，弹性纤维破坏，无小血管增生及炎性细胞浸润，而纤维化、钙化少见。     

Interrupted aortic arch: Natural history and operative results

Summary The chances of survival for patients with interruption of the aortic arch depend mainly on early recognition and medical treatment before symptoms of cardiogenic shock appear, and specifically on early operative repair after the exact diagnosis has been established. Accurate angiography with visualization of the interrupted aortic arch and delineation of associated cardiac malformations is of prime importance for the surgical management and prognosis. Among our 36 patients with interrupted aortic arch, 27 were operated on. The operative mortality in 22 patients with associated ventricular septal defect (VSD) and persistent ductus arteriosus (PDA) was reduced from 43% (in seven patients seen up until 1979) to 7% (in 15 patients seen since 1980). One patient with interrupted aortic arch type C and another infant with associated truncus arteriosus were successfully corrected on day 9 and day 17 of life, respectively. In the patients with associated VSD and PDA as well as in the one patient with associated truncus arteriosus, the primary correction—direct anastomosis of the interrupted segments without prosthesis and VSD closure and in the case with truncus, the additional positioning of a valve-bearing allograft conduit from the right ventricle to the pulmonary artery—has been more successful than a two-step approach with initial pulmonary artery banding.     

Premature closure of the foramen ovale with levoatriocardinal vein

Two cases of the hypoplastic left heart syndrome with premature closure of the foramen ovale and levoatriocardinal veins are described and the literature is reviewed. One of the patients is the only case with both mitral and aortic valve atresia. The other is associated with the asplenia syndrome, double-outlet right ventricle without ventricular septal defect, and an anomalous connection of the left atrium to the right auricle.     

Small aortic valve annulus in children with fixed subaortic stenosis

Summary Twenty-one hearts with fixed subaortic stenosis (FSAS) were examined pathologically. Thirty children with no hemodynamically significant heart disease, 31 children with valvar aortic stenosis, and 25 children with FSAS were studied by echo- and angiocardiography. The following conclusions were drawn: (1) Patients with FSAS often have abnormal aortic valve leaflets as well as small aortic valve annulus. (2) A small aortic annulus/descending aorta ratio is probably present at birth, and may decrease with increasing age. (3) In some patients with FSAS the aortic valve annulus is too small for simple resection of the fibroelastic tissue. A Konno operation is needed for these patients. (4) M-mode echocardiography has not been useful in identifying abnormally small aortic valve annulus in FSAS patients.     

Retrograde transfemoral catheterization of the left ventricle in children with aortic valve stenosis

Summary In 19 consecutive children with aortic valve stenosis, the left ventricle was entered retrogradely with a Gensini catheter guided by a tip-deflector guidewire which could produce any desirable degree of curvature at its tip. In all patients, the aortic valve was retrogradely traversed for measurement of the pressure gradient (mean gradient=53 mmHg, mean valve area=0.36 cm²), and left ventriculography. No complications were encountered. This technique is safe, simple, and effective in retrograde catheterization of the left ventricle in children with aortic stenosis.     

Corrected Transposition of the Great Arteries with Isolated Aortic Coarctation: In Utero Echocardiographic Diagnosis

Physiologically corrected transposition of the great arteries (cTGA), defined by discordant atrioventricular and ventriculoarterial connections, is an uncommon congenital cardiac malformation. It rarely exists without associated cardiac anomalies, the most common of which are ventricular septal defect, pulmonary outflow obstruction, tricuspid valve (systemic) deformity, and rhythm disturbances. Conversely, hypoplasia of the systemic ventricle and systemic inflow or outflow obstructions have seldom been reported, although their recognition may significantly influence surgical repair and the patient's prognosis. We report a case of cTGA with complete heart block, moderate hypoplasia of the systemic ventricle, and severe aortic coarctation that was echocardiographically diagnosed in utero at 30 weeks' gestation because of fetal growth retardation and persistent fetal bradycardia. After delivery the patient underwent epimyocardial pacemaker implantation and aortic coarctation repair at 2 weeks of age. Unfortunately, the patient died on the seventh postoperative day because of systemic ventricular hypertrophy. Although it is well known that fetal echocardiography may reliably diagnose uncommon congenital cardiac malformations, to the best of our knowledge, this paper represents the first reported case of antenatal diagnosis of this complex anomaly.     

Morphologic Features of the Hypoplastic Left Heart Syndrome-A Reappraisal

The report describes the morphologic features of 102 specimens with hypoplasia of the chambers of the left heart, all with either a concordant atrioventricular connection (66 cases) or absence of the left atrioventricular connection, the right atrium being connected to a dominant right ventricle (36 cases). Either the aorta was connected to the left ventricle, having a patent valve in 23 cases and an imperforate valve in 5, or else the aortic trunk was atretic (74 cases). It was not possible to determine with certainty the ventricular origin of the aorta when its trunk was atretic, but in all hearts but 1 it seemed to be connected to the left ventricle. The atrial septum was intact in 11 hearts and grossly restrictive in a further 8. Deviation of the atrial septum relative to the infolded atrial roof (septum secundum) was seen in 32 specimens. The ventricular septum was intact in 88 hearts. The length of the left ventricle compared to the right was greatest in the 14 hearts with a ventricular septal defect. The left ventricular length was also significantly greater in hearts with a patent aortic valve. The state of the atrial septum, in contrast, bore no relationship to the dimensions of the left ventricle. Aortic coarctation was found in 44 of the hearts, and in all but 2 the shelf lesion was preductal in location. Coarctation was significantly more frequent in those hearts in which the ascending aorta was less than 3 mm in diameter. The anatomic findings are discussed in relation to recent advances in the surgical palliation of these malformations.     

Morphologic features of the hypoplastic left heart syndrome--a reappraisal

The report describes the morphologic features of 102 specimens with hypoplasia of the chambers of the left heart, all with either a concordant atrioventricular connection (66 cases) or absence of the left atrioventricular connection, the right atrium being connected to a dominant right ventricle (36 cases). Either the aorta was connected to the left ventricle, having a patent valve in 23 cases and an imperforate valve in 5, or else the aortic trunk was atretic (74 cases). It was not possible to determine with certainty the ventricular origin of the aorta when its trunk was atretic, but in all hearts but 1 it seemed to be connected to the left ventricle. The atrial septum was intact in 11 hearts and grossly restrictive in a further 8. Deviation of the atrial septum relative to the infolded atrial roof (septum secundum) was seen in 32 specimens. The ventricular septum was intact in 88 hearts. The length of the left ventricle compared to the right was greatest in the 14 hearts with a ventricular septal defect. The left ventricular length was also significantly greater in hearts with a patent aortic valve. The state of the atrial septum, in contrast, bore no relationship to the dimensions of the left ventricle. Aortic coarctation was found in 44 of the hearts, and in all but 2 the shelf lesion was preductal in location. Coarctation was significantly more frequent in those hearts in which the ascending aorta was less than 3 mm in diameter. The anatomic findings are discussed in relation to recent advances in the surgical palliation of these malformations.     

Persistent truncus arteriosus: Pathologic anatomy in 54 cases

Summary Fifty-four specimens of heart with persistent truncus arteriosus (PTA) were reviewed anatomically. According to the Collett-Edwards classification [11] there were 28 examples of type I and 26 type II. The sex distribution was equal. The number of the truncal cusps ranged from one to four (42% tricuspid, 30% bicuspid, 24% quadricuspid, and 4% unicommissural). A unicommissural truncal valve has not been previously reported. In 72% of cases, the truncal valve leaflets were thickened or dysplastic. Two valves were stenotic. The truncus arteriosus originated from both ventricles equally in 42% of the cases, predominantly from the right ventricle in 42%, and predominantly from the left ventricle in 16% of the cases. In unoperated cases of PTA originating predominantly from the right ventricle, it appeared to us that usual operative correction might result in left ventricular outflow obstruction. Variations in coronary arterial origins and patterns were present in nearly half of the cases. A single coronary artery was observed in ten cases (18.5%). Stenosis of the ostium of one coronary artery was seen in each of four cases (7%). High posterior origin of the left coronary artery was observed in ten cases (18.5%). Among the associated cardiovascular anomalies, the most common were right aortic arch (36%) and interruption of the aortic arch (11%). Three cases with the latter condition exhibited crossed pulmonary arteries. Isolated cases with tricuspid atresia, vascular sling (left pulmonary artery arising from right pulmonary artery), and persistent common atrioventricular canal were encountered.     

Outflow Tract Abnormalities in Atrioventricular Canal Malformations

Atrioventricular canal malformations are commonly regarded as being arrests of development of normal cardiac septation since their morphology strongly resembles the normal heart of Carnegie stages 14 through 18. Similarly, the spectrum of outflow tract abnormalities, which includes truncus arteriosus, transposition of the great arteries, double outlet right ventricle, and tetralogy of Fallot, has been interpreted as a developmental arrest because these malformations resemble the normal embryonic outflow tract in Carnegie stages 14 through 18, respectively. The causes of the developmental arrests in these two classes of malformations are unknown. Observation of an unusual autopsy case with features of both atrioventricular canal defect and tetralogy of Fallot prompted us to review the outflow tract morphology in 38 hearts with an atrioventricular canal malformation and two semilunar valves to determine if there was evidence to support the idea that both conditions may have the same pathogenesis. In all 38 hearts there was fibrous continuity between an anterior mitral leaflet and an aortic valve, which by anatomic definition means that no case had truncus arteriosus, transposition of the great arteries, or double outlet right ventricle. There were three cases with coarctation of the aorta, a lesion which arises when blood flow in the pulmonary trunk exceeds aortic flow during early development. There were four cases with pulmonary to aortic valve caliber ratios similar to those found in tetralogy of Fallot but the aortic-to-pulmonary valve angle relative to the heart base ranged over the full spectrum of angles seen in normal hearts and those with tetralogy of Fallot. Furthermore, this angle showed the same range of values for partial and complete canal defects, and did not correlate with patient age or ratio of pulmonary to aortic valve caliber. We conclude that the pathogenesis of the spectrum of outflow tract developmental arrests is different from that of atrioventricular canal malformations.     

Aortic stenosis

Valvular aortic stenosis in pediatric age group is mostly congenital in origin. The aortic valve may be unicuspid, bicuspid, tricuspid or rarely quadricuspid. Left ventricle undergoes concentric hypertrophy secondary to obstruction to its outflow tract. In neonatal aortic stenosis, left ventricle may be hypoplastic. The pathophysiology and clinical presentation vary with the age of onset and severity of obstruction. Echocardiography and Doppler are indispensible for the diagnosis of aortic stenosis and its severity. Cardiac catheterization is not necessary for the diagnosis, however it is performed as a part of balloon aortic valvuloplasty in severe cases. Balloon valvuloplasty is an effective alternative to surgery in pédiatrie age group. Some of these patients require surgical valve repair or replacement on follow-up. Neonates and young infants with critical aortic stenosis present with cardiogenic shock and need aggressive treatment with prostaglandin E1 infusion along with inotropic support. In experienced hands, balloon valvuloplasty is a safe procedure in neonates and infants with critical stenosis. Patients with mild and moderate aortic stenosis may be left on medical follow-up.     

Reconstruction of the right ventricular outflow tract with a conduit in congenital heart disease.

A series of five patients with complex cyanotic congenital cardiac malformations underwent surgical reconstruction of the right ventricular outflow tract using a Dacron conduit with a porcine aortic valve. All patients survived and all have shown clinical improvement. At cardiac catheterization postoperatively, a pressure gradient of between 20 and 50 mm Hg across the conduit was found in all patients. This surgical approach to patients necessitating reconstruction of the right ventricular outflow tract is effective and appears to have the best long-term results.     

Coronary Artery Dilatation and Aortic Outflow Tract Enlargement in Children with Unicommissural Aortic Valves

We evaluated the aortic outflow tract (AOT) and coronary artery dimensions in pediatric patients with unicommissural aortic valves. A retrospective review of an echocardiographic database identified 37 patients with unicommissural aortic valves. A total of 115 echocardiograms were reviewed, and the right coronary artery (RCA), left main coronary artery (LM), left anterior descending coronary artery aortic valve annulus, aortic root, sinotubular junction (STJ), and ascending aorta were measured and z scores determined. The aortic stenosis peak gradient and the amount of aortic regurgitation (AR) were also measured. The RCA diameter (z score, 1.85 ± 1.8, p = 0.03) and LM diameter (z score, 1.74 ± 1.47, p = 0.04) are significantly dilated, as are all the AOT measurements: aortic annulus (2.02 ± 1.9, p = 0.02), aortic root (2.25 ± 1.9, p = 0.02), STJ (2.22 ± 1.74, p = 0.01), and ascending aorta (4.38 ± 2.03, p < 0.001). Longitudinal follow-up showed that there was no significant variation over time in any variable. The AOT measurements were significantly correlated with each other. A trend was found in which an increasing amount of AR gave an increase in AOT measurements. The aortic gradient was not significantly associated with any measurement. Our study population demonstrated significant dilatation of the RCA and LM as well as the AOT. The dilatation of the AOT structures is likely caused by the same mechanism that accounts for the AOT dilatation in patients with bicommissural aortic valves. Dilatation of the coronary arteries may represent an intrinsic abnormality in the vessel wall. Further studies are needed to define possible changes. Work was performed at Johns Hopkins Hospital, Baltimore, MD 21287, USA.     

Morphologic Analysis of Common Atrioventricular Valves in Patients with Right Atrial Isomerism

The objective of the study was to examine the relation between the morphology of the common atrioventricular valve and regurgitation of the valve in patients with right atrial isomerism. We examined seven consecutive patients with documented right atrial isomerism who subsequently underwent postmortem examination during a 10-year period. The degree of regurgitation and the diameters of the common valve were evaluated via cineangiography, and the site of regurgitation was evaluated by echocardiography. The morphology of the common atrioventricular valve was assessed further at autopsy. Cineangiography revealed valve diameters ranging from 14.8 to 27.8 mm (mean 20.9 mm). Valvar regurgitation was revealed within 2 months of birth in all patients. Regurgitation abruptly worsened in three patients after placement of a Blalock–Taussig shunt or a central shunt and postintubation. Autopsies revealed that the common atrioventricular valve consisted of four leaflets in five patients, and three leaflets in two. The anterior leaflets were large and protruding in all patients, and the lateral leaflets were thickened in six. All patients had a mass consisting of the left lateral leaflets and chordae with direct attachment of the chordae to the ventricular muscle (the right lateral leaflet was attached to the ventricular muscle and immobile in one patient). The lateral leaflets clung to the ventricular wall and exhibited poor movement in six patients. Leaflets with poor mobility corresponded to the regurgitant valvar site as assessed by echocardiography in six patients; and the regurgitation in three patients with acute deterioration occurred at the valvar side with poor mobility. It is concluded that the common atrioventricular valve in patients with right atrial isomerism has morphologic characteristics that may be associated with valvar regurgitation and malignant potential for abrupt deterioration after replacement of systemic–pulmonary shunting.     

Congenitally corrected transposition of the great arteries: the systemic right ventricle

L-Transposition of the great arteries (L-TGA) is characterized by atrioventricular and ventriculoarterial discordance such that the morphologic right ventricle and tricuspid valve directly provide systemic cardiac output. The ability of the right ventricle to support the systemic circulation is often complicated by associated cardiac defects which provide numerous potential mechanisms for the development of ventricular dysfunction. Theoretical risk factors for right ventricular failure include volume overload, systemic afterload, conduction and rhythm disturbances, associated left ventricular pressure and geometry, coronary artery anomalies, surgical injury, pregnancy, hypoxemia, and advancing patient age. The high prevalence of associated lesions including anomalies of the conduction system and tricuspid valve predispose these patients to systemic right ventricular failure which is likely to alter survival in this uncommon form of congenital heart disease.     

Surgical Strategy for Severe Aortic Hypoplasia and Aortic Stenosis With Ventricular Septal Defect and Normal Left Ventricle

At our institution, the strategy for patients with bicuspid aortic valve, aortic valve stenosis (<5 mm), and aortic hypoplasia [hypoplastic aortic arch, coarctation of the aorta (CoA), or interrupted aortic arch (IAA)] with ventricular septal defects (VSDs) as well as normal left ventricular (LV) volume and mitral valve size consists of two parts. The Norwood operation is applied as the first palliation for this group of patients. Second, the decision whether the patients are to undergo the Rastelli operation or a univentricular repair is made depending on the size of the right ventricle after the Norwood operation. This study aimed to examine whether the aforementioned surgical strategy for this group of patients is adequate or not. Seven patients undergoing the Norwood operation as the first palliation for bicuspid aortic valve, aortic valve stenosis (<5 mm), and aortic hypoplasia with VSDs as well as normal LV volume and mitral valve size between February 2005 and March 2010 at Kitasato University Hospital and the Gunma Children’s Medical Center were reviewed. Postoperative serum B-type natriuretic peptide (BNP) and central venous pressure (CVP) were measured in the patients undergoing the staged Norwood–Rastelli operation to assess whether the authors’ right ventricular end-diastolic volume index (RVEDVI) cutoff (80 % of normal) is adequate. At this writing, all seven patients are alive after a mean follow-up period of 58.8 ± 17.8 months. They all had aortic valve stenosis of <5 mm and a bicuspid aortic valve. Four patients had a diagnosis of CoA with VSD, and three patients had IAA with VSD. Six patients underwent biventricular repair, and one patient had univentricular repair due to the small RVEDVI (74 % of normal). The patients with 80–90 % of normal RVEDVI had higher BNP and higher CVP than those with more than 90 % of normal RVEDVI after the Rastelli operation, whereas the patient undergoing the Fontan operation had a low BNP level. In conclusion, the described strategy for patients with severe aortic hypoplasia and aortic stenosis with VSD as well as normal LV and mitral valve size is reasonable.