Isolated left-sided scimitar vein connecting all left pulmonary veins to the right inferior vena cava.

When the common pulmonary vein fails to develop, the embryonic connections of the pulmonary veins to one or more of the systemic veins almost always persist. Anomalous pulmonary venous connections to the inferior vena cava (IVC) are typically characterized by hypoplasia of the involved pulmonary veins and pulmonary artery, as well as abnormal parenchyma of the involved lung. Such cases have been described as "scimitar syndrome." We report the case of a young female patient in whom all the left pulmonary veins converged into a common vessel that drained into the IVC but who had a normal left pulmonary artery and left lung. Surgical intervention was successful, and our patient is still alive.

Biatrial or left atrial drainage of the right superior vena cava: anatomic, morphogenetic, and surgical considerations--report of three new cases and literature review.

Since the posterior wall of the right superior vena cava (RSVC) is contiguous with the anterior wall of the right upper pulmonary veins, a localized defect in this common wall may create a cavopulmonary venous confluence without eliminating the normal connection of the same right pulmonary veins with the left atrium (LA). Through this defect, blood of the unroofed right pulmonary veins will drain into the RSVC and right atrium (RA), and blood from the RSVC may shunt into the right pulmonary veins and LA. Hemodynamically, the RSVC will become biatrial. If the RSVC blood flows preferentially into the LA, its right atrial orifice will become stenotic or even atretic. If atretic, the normally positioned RSVC will drain entirely into the LA. In this report, we present the clinical and anatomical findings of two postmortem cases with biatrial drainage of the RSVC. We also document the clinical, echocardiographic, angiocardiographic, and surgical data of a living patient with left atrial drainage of the RSVC and tetralogy of Fallot with pulmonary atresia. The relevant literature and surgical treatment are reviewed, and the morphogenesis of the biatrial and left atrial RSVC is considered.

Surgical closure of apical ventricular septal defects through a right ventricular apical infundibulotomy.

BACKGROUND: We present a new understanding of the anatomic position of apical ventricular septal defects and its surgical relevance. These defects occur between the left ventricular apex and the infundibular apex, rather than between the left and right ventricular apices. Often a sizable apical recess, the infundibular apex lies anteriorly and inferiorly to the moderator band and is the most leftward part of the right ventricle. METHODS: Four patients (2 boys and 2 girls) with a mean age of 109 days (range, 48 to 217 days) underwent patch closure through an apical infundibulotomy, which allowed complete visualization of the muscular apical ventricular septal defect. RESULTS: There were no early or late deaths at operation. No significant residual shunt at ventricular level was detected by postoperative two-dimensional and Doppler echocardiography. Intraoperative comparison of right atrial and pulmonary arterial blood samples showed a difference of less than 5%. At a mean follow-up of 18 months, all the patients are asymptomatic and growing well. CONCLUSIONS: The successful outcome of these 4 patients indicates that surgical closure of apical ventricular septal defects can be achieved safely and completely in early infancy through a limited right ventricular apical infundibulotomy. Long-term follow-up of these and similar patients is needed to provide further evaluation of this approach.

Mitral and aortic atresia associated with hypoplastic right lung, crossover segment of right lower lobe, and anomalous scimitar-like right pulmonary venous connection with inferior vena cava: clinical, angiocardiographic, and autopsy findings in a rare case.

A newborn female infant was found to have a unique and previously unreported group of anomalies: (1) mitral and aortic atresia with a highly obstructive atrial septum; (2) hypoplasia of the right lung with a crossover segment involving the right lower lobe; (3) normally connected pulmonary veins, two from the left lung and one from the right; and (4) a large anomalous branch of the right pulmonary vein of scimitar configuration that anastomosed with the normally connected right pulmonary vein and with the inferior vena cava (IVC). The scimitar vein appeared obstructed at its junction with the right pulmonary vein and at its junction with the inferior vena cava within the hepatic parenchyma. To our knowledge, this is the first report of a scimitar-like vein coexisting with mitral and aortic atresia and connecting both with the right pulmonary vein and with the inferior vena cava. The highly obstructed left atrium was partially decompressed by retrograde blood flow via the normally connected right pulmonary vein to the anomalous scimitar venous pathway and thence to the inferior vena cava via a pulmonary-to-IVC collateral vein.

Interrupted inferior vena cava in asplenia syndrome and a review of the hereditary patterns of visceral situs abnormalities.

We present the clinical and postmortem findings of the first photographically documented case of asplenia and interrupted inferior vena cava and the anatomic findings of 5 previously reported cases. A brief review of the various hereditary patterns of visceral situs abnormalities suggests that, at least in some cases, the asplenia and polysplenia syndromes are etiologically and pathogenetically interrelated.

Absent right superior vena cava in visceroatrial situs solitus.

Absence of the right superior vena cava (SVC) in visceroatrial situs solitus is rare (0.07% to 0.13% of congenital cardiovascular malformations), and little is known about the type and frequency of additional heart defects and arrhythmias. We reviewed previous publications and present 9 new cases. Based on 121 known cases, we found that this anomaly is typically characterized by: (1) persistence of the left SVC draining into the right atrium by way of the coronary sinus, and (2) left-sided azygos vein draining into the left SVC. Less constant features were: (3) additional cardiovascular malformations (46%), and (4) rhythm abnormalities (36%) that usually appeared related to the complications of old age. Since absence of the right SVC is clinically silent, its status should be assessed echocardiographically prior to invasive medical or surgical procedures. This is important to avoid various management difficulties during the following procedures: (1) implantation of a transvenous pacemaker, (2) placement of a pulmonary artery catheter for intraoperative or intensive care unit monitoring without fluoroscopy, (3) systemic venous cannulation for extracorporeal membrane oxygenation, (4) systemic venous cannulation for cardiopulmonary bypass, (5) partial or total cavopulmonary anastomoses; and (6) orthotopic heart transplantation and endomyocardial biopsies.

Aortic outflow obstruction in visceral heterotaxy: a study based on twenty postmortem cases.

Aortic outflow tract obstruction can complicate the clinical course and surgical management of patients with heterotaxy syndromes, but its anatomic basis has not been described in detail. In 20 postmortem cases with asplenia (n = 4) or polysplenia (n = 16), the anatomic causes of aortic outflow tract obstruction were absence of the subaortic conus in association with (1) narrowing of the subaortic outflow tract between the conal septum anteriorly and the common atrioventricular (AV) valve posteriorly in six (30%) patients; (2) aortic valvar atresia in four (25%), three with asplenia and one with polysplenia; (3) redundant AV valve leaflets in four (20%); (4) excessive AV valve fibrous tissue in four (20%); (5) marked hypoplasia of the mitral valve and left ventricle in two (10%); and (6) aneurysm of membranous septum in one (5%). One patient belonged to group (1) and (4). Aortic outflow tract obstruction was much more common with polysplenia (28%) than with asplenia (4%) (p < 0.001).

Juxtaposition of the morphologically right atrial appendage in solitus and inversus atria: a study of 35 postmortem cases.

Juxtaposition of the atrial appendages has previously been classified positionally, left sided being more frequent than right sided. In our study of 35 postmortem cases, juxtaposition was analyzed morphologically for the first time. Juxtaposition of the morphologically right atrial appendage (JRAA) was always left sided with solitus atria (34 cases) but was right sided with inversus atria (1 case), the latter patient being the first documented case of JRAA with atrial inversion. Thus in patients with JRAA, the sidedness of the juxtaposition depends on the type of atrial situs that coexists. Frequent associated malformations included tricuspid valve anomalies (21 [60%] of 30), hypoplasia of the right ventricular sinus (26 [74%] of 35), and an abnormal conus (subaortic or bilateral) in 100%. Hypoplasia of the right ventricular sinus, plus malformation of the conus, appears to be important in the morphogenesis of JRAA.

Juxtaposition of the morphologically left atrial appendage in solitus and inversus atria: a study of 18 postmortem cases.

Juxtaposition of the morphologically left atrial appendage (JLAA) was analyzed for the first time primarily morphologically, rather than primarily positionally. In a series of 18 postmortem cases, JLAA with solitus atria occurred in 16 (89%) cases, and JLAA with inversus atria was found in 2 (11%) cases. JLAA with solitus atria was always right-sided, whereas JLAA with inversus atria was left-sided. Thus the sidedness of the malposed (juxtaposed) LAA depended on the atrial situs, not on the type of ventricular loop (contrary to what was formerly thought). The anatomic features associated with JLAA are essentially the opposite of those with JRAA. JLAA was characterized by left atrial outlet obstruction (69%), left ventricular hypoplasia (67%), and aortic outflow tract obstruction (39%). JLAA usually has a hypoplastic left ventricle and normal conus, whereas JRAA typically has a hypoplastic right ventricle and abnormal conus.

Systemic and pulmonary venous connections in visceral heterotaxy with asplenia. Diagnostic and surgical considerations based on seventy-two autopsied cases.

To facilitate the preoperative diagnosis and surgical management of visceral heterotaxy and asplenia, 72 postmortem cases were reviewed with particular attention focused on the systemic and pulmonary venous connections. The superior vena cava was bilateral in 51 cases (71%), but in 9 cases one of the superior venae cavae was partly or totally atretic. Patent bilateral superior venae cavae were found in 42 cases (58%) and the superior vena cava was unilateral in 21 (29%). Although the inferior vena cava was never interrupted, a prominent azygos vein was found in 6 cases (8%). Some hepatic veins drained separately from the inferior vena cava in 20 cases (28%). An intact coronary sinus was rare (2 cases, 3%). Anomalous pulmonary venous connection to a systemic vein was total in 42 (58%) of 72 and partial in 2 (3%) of 72, with obstruction in 24 (55%) of 44. Abnormal pulmonary artery branches (severe hypoplasia, localized stenosis, or discontinuity) were present in 21 (29%), and these obstructive arterial anomalies were associated with a significantly higher prevalence of anomalous pulmonary venous connection (p < 0.01) and of pulmonary venous obstruction (p < 0.01). Cardiac pulmonary venous connections were found in 28 (39%), with the pulmonary veins and the inferior vena cava entering the same atrium in 10 (36%) of 28.

Partial or total direct pulmonary venous drainage to right atrium due to malposition of septum primum. Anatomic and echocardiographic findings and surgical treatment: a study based on 36 cases.

The clinical and anatomic findings in 36 patients (21 postmortem cases and 15 living patients) with partially anomalous (16 [44%]) or totally anomalous (20 [56%]) pulmonary venous drainage directly to the right atrium constitute the material basis of this report. Displacement of septum primum--leftward in atrial situs solitus or rightward in atrial situs inversus--was present in all and appeared responsible for the anomalous pulmonary venous drainage. The pulmonary veins were connected with what normally constitutes the posterior wall of the left atrium, which became incorporated into the right atrium because of atrial septal displacement. This abnormality occurred predominantly in patients with visceral heterotaxy, usually with polysplenia, or rarely with asplenia or a normally formed spleen. Poor development or absence of septum secundum appeared responsible for the malposition of septum primum. Echocardiographic recognition of the displacement of septum primum facilitated surgical management.

Sinus venosus defects: unroofing of the right pulmonary veins--anatomic and echocardiographic findings and surgical treatment.

To clarify the nature of so-called sinus venosus atrial septal defects, the echocardiographic findings in 41 patients undergoing surgery at Children's Hospital, Boston, from March 1986 to October 1992 were reviewed, and four heart specimens with this anomaly were reassessed. Our conclusion, clearly demonstrated echocardiographically, is that sinus venosus defects result from a deficiency in the wall that normally separates the right pulmonary veins from the SVC and the RA. This deficiency unroofs the right pulmonary veins, permitting them to drain into the SVC or into the RA. An interatrial communication is almost always present and is posterior or posterosuperior to the fossa ovalis. This interatrial communication is the orifice of the unroofed right pulmonary veins rather than a defect in the atrial septum.

Total anomalous pulmonary venous drainage in newborns with visceral heterotaxy.

Children with visceral heterotaxy often present with total anomalous pulmonary venous drainage (TAPVD) associated with univentricular congenital heart disease. We reviewed our experience with the primary surgical management of this lesion under these circumstances. Over a recent 10-year span, 38 patients within the first 3 days of life were admitted to our institution and underwent primary palliation. Twenty-one of them had TAPVD, 18 to a systemic vein. Twelve (67%) of these 18 were seen with obstruction of the anomalous connection and underwent emergency operation. In 7 patients, repair of TAPVD was combined with a systemic-pulmonary artery shunt because of additional obstruction of the pulmonary blood supply, with two deaths. One patient had primary shunting and then repair of TAPVD. Four patients underwent repair of TAPVD alone. Two of them then showed signs of insufficient pulmonary blood flow, received a shunt in a second procedure, and subsequently died. Early mortality in the group with obstructed TAPVD was thus 4 (33%) of 12 patients. Statistical analysis of all 38 patients (univariate analysis, chi 2 testing) showed that neither the presence of TAPVD (p = 0.7) nor TAPVD repair alone (p = 0.8) or with shunting (p = 0.8) was a definite risk factor for early death. The performance of a shunt during the first operation, however, was associated with lower early mortality (p = 0.03). Total anomalous pulmonary venous drainage is a common finding in newborns with visceral heterotaxy. Its presence and its subsequent early repair (requiring cardiopulmonary bypass) do not increase the mortality risk. The need of a concomitant shunt in obstructed TAPVD can initially be underestimated.

Conal anatomy in 119 patients with d-loop transposition of the great arteries and ventricular septal defect: an echocardiographic and pathologic study.

OBJECTIVES: We sought to study the range of conal morphology in transposition of the great arteries with ventricular septal defect and their embryologic and surgical implications. BACKGROUND: Conal anatomy in transposition of the great arteries and ventricular septal defect is variable and might affect surgical repair. METHODS: Conal anatomy was explored using two-dimensional echocardiography in 119 patients with transposition of the great arteries and a large ventricular septal defect who presented between 1984 and 1991. The influence of conal anatomy on surgical technique was determined by review of the operative reports. Specimens of transposition of the great arteries with unusual conal anatomy were selected from the Cardiac Registry for comparison with the echocardiograms. RESULTS: One hundred five patients (88.2%) had subaortic conus only with no subpulmonary conus (Group 1). Subarterial conus was present bilaterally in eight patients (6.7%) (Group 2). Four patients (3.4%) had only subpulmonary conus with no (or minimal) subaortic conus (Group 3). Among these four patients, the aorta was posterior to the pulmonary artery in one patient, side by side relative to the pulmonary artery in two patients and slightly anterior in the fourth patient. Subarterial conus was absent bilaterally in two patients (1.7%) (Group 4); the aorta was slightly posterior in one and side by side with the pulmonary artery in the other. CONCLUSIONS: This variability of conal anatomy in transposition of the great arteries with ventricular septal defect implies four mechanisms by which transposition can occur. The conal anatomy appeared to affect surgical repair in Groups 1 and 2 insofar as it influenced ventricular outflow tract obstruction. In Groups 3 and 4, an arterial switch operation was performed in four of the six patients. The posterior location of the aorta obviated the need for the Lecompte maneuver in two of these four patients. In the remaining two cases in Groups 3 and 4, the condition was repaired by directing the left ventricular outflow across the ventricular septal defect to the aorta using a patch, with or without placement of a conduit from the right ventricle to the pulmonary artery.

Characteristics of structural heart defects in trisomy 9 and their relationship to those in trisomy 13, 18, and 21.

The hearts from two live-born full-term infants with nonmosaic trisomy 9 (one complete trisomy 9, one partial trisomy 9) were studied after death. Both demonstrated conal and valvular anomalies associated with ventricular septal defects. These specific malformations are discussed in relation to published cases of trisomy 9 and the cardiac defects of other autosomal trisomies (13, 18, and 21).

Predicting aneuploidy in fetuses with cardiac anomalies: significance of visceral situs and noncardiac anomalies.

To determine whether the risk of aneuploidy in fetuses with cardiac anomalies is affected by abnormal visceral situs or coexisting noncardiac anomalies (NCA), were reviewed 125 cases in which a structural cardiac anomaly was detected by prenatal sonography. Forty-three of the 125 fetuses (34%) had an abnormal karyotype (31 autosomal trisomies, 12 other). None of the 13 fetuses with abnormal visceral situs had an abnormal karyotype, whereas an abnormal karyotype was present in 43 of 112 with normal visceral situs (P < 0.01, Fisher's exact test). The karyotype was abnormal in 33 of 52 (63%) with coexisting NCA and in only 10 of 73 (14%) without coexisting NCA (P < 0.001, chi-square). Therefore, among fetuses with structural cardiac anomalies, abnormal visceral situs is strongly predictive (100% in our series) of normal karyotype, whereas the presence of coexisting NCA significantly increases the risk of aneuploidy. These findings can help guide recommendations concerning prenatal karyotyping.

Mitral atresia with a large left ventricle and an underdeveloped or absent right ventricular sinus: clinical profile, anatomic data and surgical considerations.

In mitral atresia with a large left ventricle, the tricuspid valve is either straddling and biventricular or entirely left ventricular. To learn how to assess the identity of the tricuspid valve in such cases 15 heart specimens were examined as well as the echocardiograms of 10 living patients. When the right ventricular sinus was underdeveloped (11 cases), a straddling tricuspid valve was present; when it was absent (14 cases), the tricuspid valve was entirely left ventricular. Regardless of biventricular or exclusively left ventricular attachments, the tricuspid valve was tricommissural (at postmortem examination or on echocardiography) in 22 cases (88%). Its chordal attachments showed considerable variations but were usually paraseptal or on the ventricular septal crest or conal septum. When biventricular, the tricuspid valve straddled through an inlet ventricular septal defect. Clinical or anatomic evidence, or both, of tricuspid regurgitation was present in 14 cases (56%). It is concluded that 1) the identity of the atrioventricular valves is reflected in their chordal attachments more accurately than in their leaflet morphology and depends primarily on the type of ventricular loop present; 2) as a rule, the tricuspid valve is right-sided in D-looped and left-sided in L-looped ventricles; 3) valve identity expressed as the number and position of the papillary muscle attachments is generally recognizable echocardiographically and can be used to diagnose the type of ventricular loop that is present; and 4) the presence and degree of tricuspid regurgitation deserve attention when choosing optimal palliative surgery.

Double-inlet single left ventricle: echocardiographic anatomy with emphasis on the morphology of the atrioventricular valves and ventricular septal defect.

The echocardiographic anatomy of double-inlet single left ventricle was studied in 57 patients, aged 1 day to 27 years (mean 6 years); the variables examined included morphology, size and function of the atrioventricular (AV) valves and ventricular septal defect and their relation to pulmonary stenosis, aortic stenosis and aortic arch obstruction. The visceroatrial situs was solitus and the heart was in the left side of the chest in all 57 patients. A d-loop ventricle was present in 21 patients and an l-loop ventricle in 36. The great arteries were normally related (Holmes heart) in 8 patients and transposed in 49. In all hearts, the right AV valve was anterior to the left AV valve. In 53 patients, the tricuspid valve (right valve in d-loop and left valve in l-loop) was closer to and had attachments on the septum. The tricuspid valve straddled the outflow chamber in eight patients. No significant difference was noted in the mean AV valve diameter when comparing mitral and tricuspid valves within the same group or between the groups with a d- or l-loop ventricle. The right AV valve diameter had a significant direct correlation with the aortic valve diameter and the size of the ventricular septal defect regardless of ventricular loop. Both AV valves were functionally normal in 34 patients. Among patients with AV valve dysfunction, the tricuspid valve tended to be stenotic in patients with an l-loop ventricle and regurgitant in patients with a d-loop ventricle. Mitral valve dysfunction was uncommon. The ventricular septal defect (46 patients) was separated from the semilunar valves in 24 patients (muscular defect) and adjacent to the anterior semilunar valve as a result of hypoplasia or malalignment, or both, of the infundibular septum (subaortic defect) in 19 patients. Multiple defects were present in three patients. The defect was unrestrictive in 26 patients, restrictive in 23 and could not be evaluated in 8. Pulmonary artery banding had been performed in 8 of the 26 patients with an unrestrictive defect and in 10 of the 23 patients with a restrictive defect. Only 4 of 19 subaortic defects compared with 16 of 24 muscular defects were restrictive. The size of the defect was significantly correlated with the measured pressure gradient. Among patients with transposition, only 2 of 13 with pulmonary stenosis had a restrictive ventricular septal defect compared with 15 of 30 without pulmonary stenosis. In patients with transposition, the defect size was significantly smaller when coarctation was present.

Straddling mitral valve with hypoplastic right ventricle, crisscross atrioventricular relations, double outlet right ventricle and dextrocardia: morphologic, diagnostic and surgical considerations.

The clinical, surgical and morphologic findings in five cases of a rare form of straddling mitral valve are presented. Three patients were diagnosed by two-dimensional echocardiography, cardiac catheterization and angiocardiography and two had diagnostic confirmation at autopsy. All five cases shared a distinctive and consistent combination of anomalies: 1) dextrocardia; 2) visceroatrial situs solitus, concordant ventricular D-loop and double outlet right ventricle with the aorta positioned to the left of and anterior to the pulmonary artery; 3) hypoplasia of right ventricular inflow (sinus) with tricuspid valve stenosis or hypoplasia; 4) large right ventricular infundibulum (outflow); 5) malalignment conoventricular septal defect; 6) straddling mitral valve with chordal attachments to the left ventricle and right ventricular infundibulum; 7) severe subpulmonary stenosis with well developed pulmonary arteries; and 8) superoinferior ventricles with crisscross atrioventricular (AV) relations. The degree of malalignment between the atrial and ventricular septa was studied quantitatively by measuring the AV septal angle projected on the frontal plane. The AV septal angle in the two postmortem cases was 150 degrees, reflecting marked malalignment of the ventricles relative to the atria. This AV malalignment appears to play an important role in the morphogenesis of straddling mitral valve. As judged by a companion study of seven postmortem cases, the more common form of straddling mitral valve with a hypertrophied and enlarged right ventricular sinus had less severe ventricular malposition than did the five rare study cases with hypoplastic right ventricular sinus. A competent mitral valve, low pulmonary vascular resistance and low left ventricular end-diastolic pressure were found at cardiac catheterization in the three living patients who underwent a modified Fontan procedure and are doing well 2.2 to 5.8 years postoperatively.