Population trends in prenatal detection of transposition of great arteries: impact of obstetric screening ultrasound guidelines.

OBJECTIVES: Dextro-transposition of the great arteries (d-TGA) is one of the most common critical neonatal heart defects, with a low detection rate antenatally. We sought to evaluate trends in the prenatal detection of d-TGA with or without ventricular septal defect (VSD) in Alberta over the past 13 years, examining the potential impact of ultrasound guidelines incorporating screening of cardiac outflow tracts, updated in 2009-2010 and in 2013, and factors affecting detection of the condition. METHODS: All fetuses and neonates with d-TGA, with or without VSD, encountered between 2003 and 2015 in the province of Alberta, were identified retrospectively. Clinical records including obstetric ultrasound reports were reviewed. Pregnancy outcome, common referral indications and associated maternal and fetal pathology in affected pregnancies were assessed. RESULTS: From 2003 to 2015, 127 cases with d-TGA were encountered in Alberta, of which 47 (37%) were detected prenatally. Prenatal detection improved over the study period, from 14% in 2003-2010, to 50% in 2011-2013, and to 77% in 2014-2015. Of the 47 fetuses with a prenatal diagnosis of d-TGA, an indication for fetal echocardiography included abnormal or poorly visualized cardiac outflows with normal four-chamber view in 46 (98%). Comorbidities were identified in 12 mothers, only five of which represented an additional reason for fetal echocardiography referral, and four fetuses had extracardiac pathology. CONCLUSION: Substantial improvement in the prenatal detection of d-TGA has been observed in Alberta over the past few years, owing to improved screening of cardiac outflow tracts on routine obstetric ultrasound examination in otherwise healthy pregnancies, and has been temporally associated with updated obstetric ultrasound guidelines suggesting that these contributed to optimized screening of affected pregnancies. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

New method to predict need for Rashkind procedure in fetuses with dextro-transposition of the great arteries.

OBJECTIVE: Prenatal congenital heart disease classification systems distinguish between critical dextro-transposition of the great arteries (d-TGA) with restriction of the foramen ovale (FO) (which requires a Rashkind procedure within the first 24 h following delivery) and d-TGA for which surgery is planned (after prostaglandin perfusion or Rashkind procedure later than 24 h after delivery). However, current prenatal diagnostic criteria for postnatal FO restriction in d-TGA are inadequate, resulting in a high false-negative rate. We aimed to identify echocardiographic features to predict the urgent need for Rashkind procedure. METHODS: We identified retrospectively 98 patients with singleton pregnancy diagnosed prenatally with fetal d-TGA at two European centers from 2006 to 2013. Two groups were compared: (1) those in whom the Rashkind procedure was performed within the first 24 h postnatally; and (2) those who did not undergo a Rashkind procedure before cardiac surgery. Exclusion criteria were: (1) no fetal echocardiography within 3 weeks prior to delivery (n = 18); (2) delivery before 37 weeks of gestation (n = 6); (3) improper or lack of measurement of pulmonary vein maximum flow velocity (n = 10); (4) lack of neonatal follow-up data (n = 9); (5) Rashkind procedure performed more than 24 h after delivery (n = 4). RESULTS: Fifty-one patients met the inclusion criteria: 29 who underwent the Rashkind procedure and 22 who did not. There were no differences between these two study groups in terms of maternal age, gestational age at time of fetal echocardiography, fetal biometric measurements, estimated fetal weight, rate of Cesarean delivery, newborn weight or Apgar score at 1 min. There were also no differences during prenatal life between the two groups in terms of fetal cardiac size (heart area/chest area ratio), rate of disproportion between left and right ventricle, FO diameter and maximum velocity of flow through the FO. However, the pulmonary vein maximum velocity was significantly higher in the group requiring a Rashkind procedure (47.62 ± 7.48 vs 32.21 ± 5.47 cm/s; P < 0.001). The cut-off value of 41 cm/s provided maximum specificity (100%) and positive predictive value (100%) at only a slight cost of sensitivity (82%) and NPV (86%). The prenatal appearance of the FO also differed between the groups, the FO valve being flat in 52% of those requiring a Rashkind procedure. CONCLUSIONS: In fetuses with d-TGA, prenatal sonographic findings of increased pulmonary venous blood flow and flattened FO valve were associated with the need for a Rashkind procedure within the first 24 h postnatally; these echocardiographic features could be used to predict prenatally a need for the procedure following delivery. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Anatomical Classifications of the Coronary Arteries in Complete Transposition of the Great Arteries and Double Outlet Right Ventricle with Subpulmonary Ventricular Septal Defect.

Objective To discuss the anatomical morphologies of the coronary arteries and frequencies of unusual coronary arteries in complete transposition of the great arteries and double outlet right ventricle (DORV) associated with a subpulmonic ventricular septal defect (VSD). Methods Between March 1999 and August 2012, 1,078 patients with complete transposition of the great arteries or DORV with subpulmonary VSD underwent arterial switch operations (ASOs) and were visually evaluated to classify their coronary artery morphology during open heart surgery. Results The coronary arteries could be classified into five patterns with several subtypes. Unusual coronary arteries were observed in 248 of the 1,078 cases, providing a frequency of 23.01%. The frequencies of the patients with transposition of the great arteries with intact ventricular septum (TGA/IVS), TGA/VSD, and DORV with subpulmonary VSD were 17.65, 23.28, and 31.84%, respectively. The most common morphologies were the right coronary artery (RCA) originating from sinus 1 and circumflex (CX) originating from sinus 2 (1R, AD; 2CX; 26.50%); the CX originating from sinus 2 (1AD; 2R, CX; 21.36%); the RCA, left anterior descending artery, and CX originating from single sinus 2 (2R, AD, CX; 13.24%). The in-hospital mortalities of the patients with or without unusual coronary arteries after ASO were 14.1 and 6.02%, respectively. Conclusion Patients with complete transposition of the great arteries or DORV with subpulmonary VSD have a high frequency of unusual coronary arteries, which might greatly impact on the mortality for ASO. Improving the preoperative diagnostic criteria for coronary artery morphology may significantly increase the success rate for ASOs.

[The segmentary classification of complex congenital heart disease or how the embryology simplified the study of these cardiopathies. The morphology of side by syde great arteries]. / La clasificación segmentaria de las cardiopatías complejas o cómo la embriología simplificó el estudio de estas cardiopatías. Las morfologías de grandes arterias lado a lado.

In the 60-70 years of last century began the systematic study of complex congenital heart disease. The group of Dr. de la Cruz at the National Heart Institute of Mexico, based the segmental analysis of these heart in experimental study of embryological development. We could include exceptions to the complex cadiopathies, adding to the segmental classification, atrial situs, ventricular loop pedicle of the great arteries, the infundibular analysis. This presentation describes for the first time as a separate entity in the segmental analysis cadiopathies with great arteries side by side as a group with a different developmental mechanism to transposition and normally related or crossed great arteries.

What Determines Whether the Great Arteries Are Normally or Abnormally Related?

The situs, or pattern of anatomic organization, of the subarterial infundibulum and of the great arteries and the degree of development of the subarterial infundibulum largely determine whether the great arteries are normally or abnormally related. There are 2 types of situs: solitus (normal) and inversus (a mirror image of solitus). Situs ambiguus means that the pattern of anatomic organization is uncertain or unknown. Infundibular development varies from absent, to atretic, to severely stenotic, to mildly or moderately stenotic; great arteries are solitus normally related or inversus normally related, respectively. When the situs of the subarterial infundibulum and the situs of the great arteries are discordant (different), then the great arteries are abnormally related. Equations indicating the situs of the infundibulum and the situs of the great arteries show whether infundibuloarterial (IA) situs concordance or discordance is present. Many types of IA anomalies typically have IA situs discordance, including transposition of the great arteries, double-outlet right ventricle, double-outlet left ventricle, and anatomically corrected malposition of the great arteries. However, tetralogy of Fallot and truncus arteriosus typically have IA situs concordance, with hypoplasia or atresia of the subpulmonary infundibulum. The relation between the great arteries in tetralogy of Fallot and in truncus arteriosus is almost normal. The IA equations demonstrate the infundibular situs, the great arterial situs, the IA situs concordance or discordance, and the degree of development of the infundibulum. The infundibular situs and the great arterial situs are the formulas or "recipes" for each of the abnormal types of conotruncal malformation.

Anatomic variability in coronary arterial distribution with regard to the arterial switch procedure.

BACKGROUND: We investigated the coronary arterial origins and course and the position of the great arteries in hearts with discordant ventriculoarterial connections. At the same time, we sought to evaluate the practicality of alphanumeric classifications in accounting for surgically relevant features of the coronary arteries. METHODS AND RESULTS: We studied 200 postmortem hearts, noting the patterns of coronary arterial branching, the vertical and horizontal location of the arterial orifices within the aortic sinuses, the course of the proximal coronary arteries in relation to the aortic wall, and the relations of the great arteries and their respective commissures. All hearts examined had concordant atrioventricular and discordant ventriculoarterial connections. We found 7 of the 8 predicted patterns for sinusal origin of the 3 major coronary arteries and identified 5 different positions of the arterial trunks relative to each other. A correlation was found between less frequent relationships of the arterial trunks and unusual patterns of coronary arterial branching, as well as with mismatch between the valvar commissures. CONCLUSIONS: The surgically relevant features of the coronary arteries in hearts with discordant ventriculoarterial connections are best described rather than classified. Correlations exist between certain, less frequent relations of the great arteries and unusual patterns of branching of the coronary arteries. The presence of unusual great arterial positions should alert the surgeon to potentially complicated arrangements of the origin and distribution of the coronary arteries.

Evolution of coronary artery pattern according to short-axis aortopulmonary rotation: a new categorization for complete transposition of the great arteries.

OBJECTIVES: We studied the correlation between coronary artery pattern and aortopulmonary rotation in complete transposition of the great arteries. BACKGROUND: Classifications of the coronary arteries in complete transposition are puzzling and incomplete. METHODS: Coronary artery anatomy and relation of the great arteries were identified at angiography, echocardiography, surgical intervention or autopsy in 76 patients with complete transposition from 1988 to 1993. Five main types (type 0 and Shaher types 1,2,4 and 9) and their similar variants of epicardial configuration were categorized into five patterns (O, I, II, IV and IX). In addition, data from 568 cases from published reports were collected for analysis. RESULTS: As the aorta rotated from a left anterior to a directly anterior location relative to the pulmonary trunk, the left anterior descending coronary artery arose from the left-hand sinus together with the right coronary artery (type 0, one case decreased to no cases); then it gradually shifted to the left to have the same origin as the left circumflex coronary artery from the right-hand sinus (type 1, 10 cases increased to 146, p < 0.0003). When the aorta rotated farther clockwise from directly anterior to right anterior (type 1, 146 cases increased to 235; type 2, 9 cases increased to 50, p < 0.0006) or from right anterior to right lateral (type 1, 235 cases decreased to 6 cases; type 2, 50 cases decreased to 20, p < 0.00000), the left circumflex coronary artery tended to move retropulmonically and originated from the left-hand sinus with the right coronary artery (type 2). When the aorta moved from right anterior to right lateral (type 2, 50 cases decreased to 20; type 4, 13 cases increased to 14, p < 0.031) or from right lateral to right posterior (type 2, 20 cases decreased to 1; type 4, 14 cases increased to 16, p < 0.0003), the right coronary artery shifted to the right-hand sinus anteaortically to join the left anterior descending coronary artery (type 4). Finally, the left anterior descending coronary artery combined with the left circumflex coronary artery (type 9, 12 cases increased to 21, p = 0.407) to become the usual pattern for normally related great arteries. Eta-square analysis showed that the evolution from pattern O to IX was dependent on clockwise aortopulmonary rotation. CONCLUSIONS: The coronary arteries in complete transposition of the great arteries can be classified into five patterns and their evolution deduced on the basis of aortopulmonary rotation. Dependence of coronary artery type on aortopulmonary rotation made it possible to anticipate the coronary pattern from the relation of the great arteries in transposition.

Anatomy of the ventricular septal defect in outflow tract defects: similarities and differences.

OBJECTIVE: The study objective was to analyze the anatomy of the ventricular septal defect found in various phenotypes of outflow tract defects. METHODS: We reviewed 277 heart specimens with isolated outlet ventricular septal defect without subpulmonary stenosis (isolated outlet ventricular septal defect, 19); tetralogy of Fallot (71); tetralogy of Fallot with pulmonary atresia (51); common arterial trunk (54); double outlet right ventricle (65) with subaortic, doubly committed, or subpulmonary ventricular septal defect; and interrupted aortic arch type B (17). Special attention was paid to the rims of the ventricular septal defect viewed from the right ventricular side and the relationships between the tricuspid and aortic valves. RESULTS: The ventricular septal defect was always located in the outlet of the right ventricle, between the 2 limbs of the septal band. There was a fibrous continuity between the tricuspid and aortic valves in 74% of specimens with isolated outlet ventricular septal defect, 66% of specimens with tetralogy of Fallot, 39% of specimens with tetralogy of Fallot with pulmonary atresia, 4.6% of specimens with double outlet right ventricle, 1.8% of specimens with common arterial trunk, and zero of specimens with interrupted aortic arch type B (P < .005). When present, this continuity always involved the anterior tricuspid leaflet. CONCLUSIONS: The ventricular septal defect in outflow tract defects is always an outlet ventricular septal defect, cradled between the 2 limbs of the septal band. However, there are some differences regarding the posteroinferior and superior rims of the ventricular septal defect. These differences suggest an anatomic continuum from the isolated outlet ventricular septal defect to the interrupted aortic arch type B rather than distinct physiologic phenotypes, related to various degrees of abnormal rotation of the outflow tract during heart development: minimal in isolated outlet ventricular septal defect; incomplete in tetralogy of Fallot, tetralogy of Fallot with pulmonary atresia, and double outlet right ventricle; absent in common arterial trunk; and excessive in interrupted aortic arch type B.

Coronary arteries in transposition of the great arteries.

The topic of coronary arteries in transposition of the great arteries (TGA) is complex and confusing despite having been the subject of several recently published reports. One hundred thirty-three autopsy specimens of uncomplicated TGA were studied, with special attention to methodologic issues in anatomic description and classification. Uncomplicated TGA was defined as congenital anomaly involving origin of the aorta from the right ventricle and of the pulmonary artery from the left ventricle. Three types of transposition were recognized ("anterior aorta," "side-by-side," and "posterior aorta") depending on the aortopulmonary relations, which were intrinsically defined by the relation of the valvular orifices of the great arteries with respect to the atrioventricular orifices. The frequency of distribution of individual coronary patterns differs substantially in the first 2 types of TGA. As in normal hearts, coronary arteries in TGA tend to originate from the facing sinuses (adjacent to the pulmonary valve); in TGA, however, variations in further distal anatomy are much more frequent. It is suggested that individual coronary patterns be described in terms of number of ostia, exact ostial location within or outside the aortic sinuses, and proximal course and distribution. The use of strict, simplified classifications of coronary patterns is discouraging because of the relevance of each individual anatomic parameter to clinical aims. Because of the aortopulmonary switch repair for TGA, this study emphasizes the surgical implications of the different coronary features.

Comparison of equilibrium radionuclide ventriculography with cardiovascular magnetic resonance for assessing the systemic right ventricle after Mustard or Senning procedures for complete transposition of the great arteries.

We assessed the utility of equilibrium radionuclide ventriculography for assessing function of the systemic right ventricle by comparing it with cardiovascular magnetic resonance (CMR) in subjects who had undergone the Mustard or Senning operations for complete transposition of the great arteries. The 95% limits of agreement for right ventricular ejection fraction by the 2 techniques were 15.8% to -16.0%, demonstrating that equilibrium radionuclide ventriculography has good agreement with CMR and provides a good alternative in cases in which CMR is not available or appropriate.

Anatomic repair of anomalies of ventriculoarterial connection associated with ventricular septal defect. I. Criteria of surgical decision.

The feasibility of anatomic repair (defined as the reconstruction of normal ventriculoarterial connection) was investigated in 104 patients who underwent an operation for anomalies of ventriculoarterial connection associated with ventricular septal defect. Three types of anatomic repair were used: intraventricular rerouting, REV (association of intraventricular rerouting with translocation of the pulmonary arterial trunk on the right ventricle), and arterial switch associated with closure of the ventricular septal defect. Intraventricular repair was considered to be the best and simplest method when possible. In the other cases, REV was indicated if pulmonary outflow tract obstruction was present, and arterial switch was performed when the tract was patent. The feasibility of intraventricular repair was related to the distances between the tricuspid valve and the semilunar valves. Preoperative measurement of these distances is an essential criterion to choose the appropriate repair of anomalies of ventriculoarterial connection associated with ventricular septal defect.

Double-outlet right ventricle. A collective review with a surgical viewpoint.

Double-outlet right ventricle (DORV) should be classified according to its various subsets. Van Praagh's symbolic terminology provides an appropriate mechanism for doing that. Each of these subsets is described in terms of its pathology, clinical characteristics, cardiac catheterization findings, and operative repair. The operative repair for each is different. The presence or absence of continuity between the semilunar and atrioventricular valves is unimportant from the standpoint of operation and should not be a criterion for classification.

Is there an anatomic basis for subvalvular right ventricular outflow tract obstruction after an arterial switch repair for complete transposition? A morphometric study and review.

The study was initiated by reports on right ventricular outflow tract obstruction in complete transposition of the great arteries after an arterial switch repair. We investigated 39 heart specimens with native, unoperated transposition of the great arteries. Of these, 14 hearts had a ventricular septal defect; 25 had an intact ventricular septum. In each heart specimen the narrowest site of the subaortic outflow tract was measured and compared with the circumference of the aortic orifice. Obstruction was considered to be present if the outflow tract circumference was less than that of the aortic orifice. In addition, the diameter of the ascending aorta immediately above the level of the valve orifices was measured and compared with that of the pulmonary trunk. An obstruction was present in the subaortic right ventricular outflow tract of two hearts (5.1%): one of the obstructions, in a neonatal heart with intact ventricular septum, was caused by a prominent supraventricular crest and anterior trabeculations; the other obstruction was an additional extensive muscular hypertrophy, in the heart of a 13-year-old patient with a similar anatomy, and a septal defect. A mismatch between the diameters of the ascending aorta and the pulmonary trunk was present in 15 of 32 hearts measured. Our observations and a review of the literature confirm that subvalvular right ventricular outflow tract obstruction in hearts with native transposition of the great arteries is infrequent. Nevertheless, the anatomic characteristics of the right ventricular outflow tract are such that the tract is intrinsically narrow and muscular hypertrophy may easily lead to obstruction. After an arterial switch operation, subvalvular obstruction could be caused by dynamic processes analogous to those observed after relief of isolated pulmonary valve stenosis. Anatomic subvalvular obstruction could be due to either an obstruction that was not identified before operation or (a purely speculative hypothesis) subtle degrees of mismatch in size between the proximal aorta and the pulmonary trunk, which may be considered irrelevant at time of operation but may also set into pace a process of ongoing adaptive infundibular hypertrophy.

Coronary artery anatomy in complete transposition of the great arteries.

Knowledge of the variations in coronary artery pattern is important in the arterial switch operation for complete transposition of the great arteries (TGA). As autopsy specimens provide the most definitive means of identifying the coronary anatomy, 255 hearts with complete TGA were reviewed by a single pathologist. The age of the patients ranged from 1 day to 34 years (mean, 2.9 years). The origin of the coronary arteries was defined as seen by an observer looking from the pulmonary artery toward the aorta. The usual pattern with the right coronary artery originating from the right hand sinus and the left coronary artery from the left hand sinus (184 cases) and the circumflex coronary artery arising from the right coronary artery (46 cases) accounted for 90% of the cases. Eleven other patterns were identified. The usual coronary artery pattern was more prevalent in TGA with the aorta in a right anterior or anterior position (74.8%) than in TGA with a side-by-side relationship of the great arteries (38.9%). In only 2 cases (0.8%) was an aortic intramural course of the left coronary artery identified. The latter 2 cases confirm our belief that an aortic intramural course of the left coronary artery or the left anterior descending coronary artery must be assumed when the vessel has an aberrant origin from the right sinus or when it is in intimate relationship with the commissure between the right and left sinuses and courses between the great arteries. In the vast majority of specimens a favorable coronary artery pattern with regard to feasibility of the arterial switch operation was encountered.

Direct reconstruction of the pulmonary artery during the arterial switch operation: an interesting surgical option with excellent hemodynamic results.

BACKGROUND: In transposition of the great arteries, reconstruction of the neo-pulmonary artery is a challenging surgical detail during the arterial switch procedure. We present early and midterm clinical and hemodynamic results of a direct reconstruction of the pulmonary artery avoiding prosthetic and autologous material. METHODS: Between 1990 and June 1996, a total of 189 patients underwent the arterial switch procedure because of D-transposition of the great vessels. Of them, 47 underwent direct pulmonary artery reconstruction. Mean age at operation was 5.2+/-4.1 days and mean weight was 3.75+/-0.85 kg. Simple transposition of the great arteries was present in 13, transposition of the great arteries plus ventricular septal defect in 27, and more complex forms of transposition of the great arteries in 7 patients. The great vessels were side-by-side in 4 patients and in the anteroposterior position in 43 patients. The technique of direct pulmonary reconstruction includes extensive mobilization of both pulmonary artery branches into the hilum, posterior incision of the mean pulmonary artery into the bifurcation, and resuspension of the posterior commissure of the neo-pulmonary valve. A large anastomosis without any tension is then performed, using the anterior remnant aortic sinus of Valsalva to fit out the expected size of the neo-pulmonary artery. RESULTS: Early mortality was 8.5% (4/47) in this particular group of patients. Postoperative echocardiography was performed before hospital discharge, 3 to 6 months postoperatively, and after a mean follow-up of 24 months. Of the 43 survivors, 37 patients had a pressure gradient across the pulmonary valve of less than 15 mm Hg. Mild pulmonary stenosis (pressure gradient of 15 to 30 mm Hg) was present in 4 and more severe supravalvar stenosis (pressure gradient > 30 mm Hg) in 2 patients. After a mean follow-up of 36 months, there was one redo operation to enlarge the right ventricular outflow tract. CONCLUSIONS: Direct reconstruction of the neo-pulmonary artery-avoiding autologous pericardium and prosthetic material-may represent an interesting option during the arterial switch operation when the great vessels lie in the anteroposterior position. This technique is simple, and the hemodynamic midterm results are very favorable. The incidence of postoperative supravalvar pulmonary stenosis is low, and there may be considerable potential for unlimited tissue growth.

Classification of hearts with overriding aortic and pulmonary valves.

Despite the clarity of the sequential segmential segmental approach to complex congenital heart malformations, the classification of hearts with overriding arterial valves remains contentious. A series of 67 hearts, all with overriding arterial valves, has therefore been studied in an attempt to provide clear and unambiguous criteria for their classification. There were 51 hearts with an overriding aortic valve, 13 hearts with an overriding pulmonary valve and 3 specimens with overriding of both valves. In each of these categories the degree of override and the underlying morphology varied considerably. The options to classify these hearts are limited. Using the "50 per cent rule" as a device to catalogue the type of connexion - irrespective of the morphology - all hearts were described in unambiguous fashion. A comparison with synonyms, as frequently used for purposes of classification, revealed that the latter are often insufficient properly to classify the basic abnormality. By classifying the type of connexion and describing the morphology separately, no basic problem remains in distinguishing between hearts with double outlet right ventricle and subpulmonary ventricular septal defect and hearts with the morphology of Fallot's tetralogy with an aorta almost exclusively arising from the right ventricle. Similarly, the classification of hearts with complete transposition and subpulmonary defect in the setting of the so-called Taussig-Bing heart is brought back to its proper perspective. Proper and consistent application of the sequential segmental approach leaves no room for ambiguity, even in complicated hearts with overriding arterial valves.

[Transposition of great arteries. Understanding its pathogenesis]. / Trasposizione delle grandi arterie. Qualche spiraglio nell'inquadramento patogenetico.

Transposition of the great arteries (TGA) is a frequent and severe cardiac defect. In patients with this malformation, diagnostic and surgical results and the long-term prognosis significantly improved in the last years. From the embryological point of view there are two main theories: 1) the anomalous infundibular rotation, and 2) the anomaly of the aortico-pulmonary septum. Both of them still present important limits. Moreover, TGA is difficult to reproduce by animal experiments, but interesting data, using retinoid acid in pregnant rats, are nowadays available, as well as there are interesting data from the epidemiologic studies on human teratologic agents. TGA is rarely associated with genetic syndromes and with additional extracardiac anomalies. A few cases are in relation with DiGeorge syndrome with deletion of chromosome 22q11. On the contrary TGA is significantly prevalent, in association with other cardiac and extracardiac anomalies, in children with lateralization defects, heterotaxy and asplenia syndrome (right isomerism). However in patients with heterotaxy and polysplenia syndrome (left isomerism) TGA is significantly more rare. In mice with mutation of Smad2 and NODAL, two genes involved in the lateralization process, some cases of TGA, with or without right isomerism of the lungs, were reported. Moreover, in families with heterotaxy some cases with congenitally corrected TGA were reported and a new gene associated with heterotaxy, CRYPTIC, can present mutations in patients with "isolated" TGA. A recent study on familiar recurrence of TGA shows in the same family some cases of TGA and of corrected TGA so that a monogenic inheritance (autosomic dominant or recessive) with variable phenotypic expression can be suggested. The normal righthand spiralization of the heart is genetically determined in cases of situs solitus and d-loop of the ventricles. This pattern is not present in cases of TGA presenting a parallel position of the great arteries. On the basis of these observations and according to new epidemiologic and genetic data some cases of TGA should be classified in the group of the anomalies of lateralization and ventricular loop. The mystery is still present but perhaps some gleams of light are appearing.

Great vessel and coronary artery anatomy in transposition and other coronary anomalies: a universal descriptive and alphanumerical sequential classification.

In patients with transposition of the great arteries, the identification of coronary anatomy is fundamental to optimal surgical outcome. A number of classifications describing the coronary vessels' origin and course in transposition of the great arteries have been published. However, all are limited to operative or pathological case series. They are often alphanumeric classifications that do not lend themselves to clinical practice; they do not consider certain important anatomical variations that may increase surgical morbidity and mortality, nor do they fully delineate coronary anatomy or define the relationship to adjacent structures seen with cardiovascular computed tomography. Using cardiovascular computed tomography for illustrative purposes, we propose and validate a universal sequential descriptive classification and an associated alphanumeric classification that may be used for all coronary anomalies with or without associated congenital heart disease.

Coronary artery anatomy in anatomically corrected malposition of the great arteries and their surgical implications.

OBJECTIVES: Coronary artery (CA) anatomy of anatomically corrected malposition of the great arteries (ACM) has not been well elucidated. We studied the CA pattern and their association with the aortopulmonary rotation (APR). METHODS: CA anatomy and APR of ACM were identified by image or surgical intervention. The degree of APR was defined by the pattern of the aortic sinus of Valsalva on the lateral angiogram or computed tomography (CT). RESULTS: Four CA types were presented in 10 patients and literatures. Six patients had the same CA type as the usual pattern in transposition of the great arteries (type 1); and two had left anterior descending (LAD) from the left-hand facing sinus that also gave rise to the right CA (RCA) (type 0). One patient had LAD from the left-hand facing sinus while RCA and circumflex artery from the right-hand facing sinus (type 10); and single CA from the anterior left-hand sinus (type 3c) was identified in another. APR was left anterior in type 1 and more lateral in types 0 and 3c; and left posterior in type 10 (p=0.001). The usual pulmonary trans-annular incision can only be performed in case of type 10 CA after posterior APR (10%, 1/10). In the majority (90%, 9/10 with the CA type 1, 0, and 3c), the RCA is in front of the pulmonary annulus, and the atrioventricular groove patch plasty posterior to the RCA had to be adopted for a trans-annular patch. CONCLUSIONS: The observed CA pattern was correlated with APR. APR identified by the aortic sinus pattern could implicate the CA patterns and the surgical options in ACM.