Cardiac Laterality: Surgical Results of Right Atrial Isomerism

Right atrial isomerism (RAI) is a complex entity with varying diagnostic and treatment outcomes due to its rarity. Treatment options range from palliative to corrective surgeries, resulting in heterogeneous outcomes. The aim of this study was to analyze the results obtained after cardiac surgery in patients with RAI. A retrospective study was conducted, including patients diagnosed with RAI who underwent cardiac surgery. Their follow-up was from 1 January 2010 to 31 March 2020. Demographic characteristics and perioperative conditions were described. Thirty-eight patients were included, the median age was 4 years (IQR 2-9.2) and 57.9% were men. The main diagnoses were atrioventricular canal (63.2%) and pulmonary stenosis (55.3%). The most common surgical procedures were modified Blalock-Taussig shunt (65.8%) and total cavopulmonary connection with an extracardiac conduit fenestrated without cardiopulmonary bypass (15.9%). We did not find any factors associated with negative outcomes in these patients. The overall survival was 86.8%, with a better outcome in those who did not require reintubation (log rank, p < 0.01). The survival of RAI was similar to other centers. Individuals with RAI should be evaluated rigorously to determine an adequate repair strategy, considering high morbidity and mortality.

Cardiac surgery in patients with atrial isomerism: Long-term results and outcomes

PURPOSE

The aim of the study was to identify, determine, and analyze the clinical and surgical outcomes of patients with atrial isomerism (AI) undergoing cardiac surgery.

METHODS

A retrospective study was carried out. Patients with diagnosis of AI undergoing cardiac surgery at the National Institute of Cardiology Ignacio Chávez, from January 1, 2010 and March 31, 2020 were included; demographic characteristics and perioperative conditions of the patients were considered.

RESULTS

Sixty-five patients were included, with an average age of 6.4 ± 4.9 years, 50.8% males. Thirty-eight (58.5%) had right atrial isomerism (RAI) and 27 (41.5%) had left atrial isomerism (LAI); univentricular physiology (78.5%) predominated. Atrioventricular septal defect (AVSD) in RAI and septal defects in LAI were identified as the main associated defects. The most common surgical procedures performed were modified Blalock-Taussig shunt (MBTS) (27.6%), MBTS with total anomalous pulmonary venous connection (TAPVC) repair (15.3%) and total cavopulmonary connection (TCPC) with an extracardiac conduit fenestrated (10.8%); 100% RAI required a univentricular approach, while in LAI it was 48.1%. Overall survival was 92.3%, with 100% survival in LAI with biventricular physiology and 86.8% in RAI with univentricular physiology.

CONCLUSIONS

The survival of our institution is similar to that of other referral centers, where patients with LAI had a better evolution than RAI; in addition, the univentricular approach was required in all with RAI. Patients with AI must undergo a rigorous evaluation to determine an adequate repair strategy, considering univentricular RAI with a high possibility of morbidity and mortality.

The multisystem nature of isomerism: left isomerism complicated by Abernethy malformation and portopulmonary hypertension

Isomerism, also referred to as "heterotaxy" is a complex set of anatomic and functional perturbations. One of the most obvious manifestations of isomerism is the disturbance of organ arrangement, such that the thoracic organs are no longer asymmetric on the left and right. We report the case of a 14-year-old female in whom exercise-induced dyspnea led to a late diagnosis of left isomerism complicated by Abernethy malformation and portopulmonary hypertension. A comprehensive evaluation revealed two anatomic left lungs and hyparterial bronchi, bilateral left atria, an interrupted inferior caval vein with azygos continuation, multiple spleens, sinus node dysfunction, hepatic hypertrophy with focal nodular hyperplasia, and absence of the portal vein. Pulmonary vasodilator therapy was initiated resulting in clinical improvement. This case exhibits unique features including a late diagnosis of isomerism with Abernethy malformation and portopulmonary hypertension. The patient's presentation, medical workup, and future treatment emphasise the importance of multidisciplinary care in children with complex multisystem disease. We review the multiple cardiac and extracardiac manifestations of isomerism.

Surgical Decision Making in Preduodenal Portal Vein: Report of Two Cases in Neonates

Preduodenal portal vein (PDPV) is a rare anomaly that can cause duodenal obstruction. PDPV is associated with other congenital anomalies, mainly cardiac and gastrointestinal. Treatment usually consists of bypassing the obstruction by duodenoduodenostomy. We report two cases of PDPV in association with atrial isomerism and malrotation with different surgical management.

Outcome of prenatally diagnosed fetal heterotaxy: systematic review and meta-analysis

OBJECTIVES

The main aim of this systematic review was to evaluate the prevalence and type of associated anomalies in fetuses with heterotaxy diagnosed prenatally on ultrasound; the perinatal outcome of these fetuses was also studied.

METHODS

An electronic search of MEDLINE, EMBASE and CINAHL databases was performed. Only studies reporting the prenatal diagnosis of isomerism were included. Outcomes observed included associated cardiac and extracardiac anomalies, fetal arrhythmia, abnormal karyotype, type of surgical repair and perinatal mortality. The analysis was stratified according to the type of heterotaxy syndrome (left (LAI) or right (RAI) atrial isomerism). Meta-analyses of proportions were used to combine data. Quality assessment of the included studies was performed using the Newcastle-Ottawa Scale for cohort studies.

RESULTS

Sixteen studies (647 fetuses) were included in the analysis. Atrioventricular septal defect was the most common associated major cardiac anomaly found both in fetuses with LAI (pooled proportion (PP), 59.3% (95% CI, 44.0-73.7%)), with obstructive lesions of the right outflow tract occurring in 35.5% of these cases, and in fetuses with RAI (PP, 72.9% (95% CI, 60.4-83.7%)). Fetal arrhythmias occurred in 36.7% (95% CI, 26.9-47.2%) of cases with LAI and were mainly represented by complete atrioventricular block, while this finding was uncommon in cases with RAI (PP, 1.3% (95% CI, 0.2-3.2%)). Abnormal stomach and liver position were found, respectively, in 59.4% (95% CI, 38.1-79.0%) and 32.5% (95% CI, 11.9-57.6%) of cases with LAI, and in 54.5% (95% CI, 38.5-70.1%) and 45.9% (95% CI, 11.3-83.0%) of cases with RAI, while intestinal malrotation was detected in 14.2% (95% CI, 2.5-33.1%) of LAI and 27.1% (95% CI, 7.9-52.0%) of RAI cases. Hydrops developed in 11.8% (95% CI, 2.9-25.6%) of fetuses diagnosed prenatally with LAI. Biventricular repair was accomplished in 78.2% (95% CI, 64.3-89.4%) of cases with LAI, while univentricular repair or palliation was needed in 17.0% (95% CI, 9.7-25.9%); death during or after surgery occurred in 26.8% (95% CI, 4.6-58.7%) of LAI cases. Most children with RAI had univentricular repair and 27.8% (95% CI, 15.5-42.1%) died during or after surgery.

CONCLUSIONS

Fetal heterotaxy is associated with a high prevalence of cardiac and extracardiac anomalies. Approximately one quarter of fetuses with heterotaxy died during or after surgery. Abnormal heart rhythm, especially heart block, is common in fetuses with LAI, while this finding is uncommon in RAI. Biventricular repair was common in LAI while univentricular repair was required in the majority of children affected by RAI. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

An alternative technique for Fontan completion in patients with widely separated connections of the inferior systemic veins to the atrial mass

Several surgical approaches for completion of a total cavopulmonary connection have been established for patients with anomalies of systemic venous connection in association with a functionally univentricular heart. We report an alternative technique designed to address the problem of widely separated inferior systemic veins, in which two extracardiac conduits were used. This technique was performed on three patients and yielded excellent short-term results, allowing us to operate on a beating heart with no need for cardioplegic arrest and aortic cross-clamping.

Ablation of Atrial Fibrillation in Patients with Congenital Heart Disease

With improved surgical techniques and medical management for patients with congenital heart diseases, more patients are living longer and well into adulthood. This improved survival comes with a price of increased morbidity, mainly secondary to increased risk of tachyarrhythmias. One of the major arrhythmias commonly encountered in this subset of cardiac patients is AF. Similar to the general population, the risk of AF increases with advancing age, and is mainly secondary to the abnormal anatomy, abnormal pressure and volume parameters in the hearts of these patients and to the increased scarring and inflammation seen in the left atrium following multiple surgical procedures. Catheter ablation for AF has been shown to be a very effective treatment modality in patients with refractory AF. However, data and guidelines regarding catheter ablation in patients with congenital heart disease are not well established. This review will shed light on the procedural techniques, success rates and complications of AF catheter ablation in patients with different types of CHD, including atrial septal defects, tetralogy of Fallot, persistent left superior vena cava, heterotaxy syndrome and atrial isomerism, and Ebstein anomaly.

Functionally Univentricular Heart With Right Atrial Isomerism and Mixed Total Anomalous Pulmonary Venous Drainage

Patients with right atrial isomerism and total anomalous pulmonary venous connection (TAPVC) in a functionally univentricular heart are a challenging subset with a high mortality rate. We present the case of a patient with univentricular heart who had right atrial isomerism and associated mixed TAPVC (supracardiac, cardiac, and infracardiac). The anatomy was delineated precisely, and the patient underwent first-stage univentricular palliation consisting of TAPVC repair and bilateral bidirectional superior cavopulmonary anastomosis.

Biventricular repair in heterotaxy patients

BACKGROUND

Heterotaxy patients' hearts may or may not be suitable for biventricular repair depending on anatomy. Even in the subset that are amenable to surgical septation, cardiac anatomy may present multiple difficulties in achieving a satisfactory repair. However, it is also well known that heterotaxy patients are not ideal candidates for univentricular repair.

METHODS

From 2007 until 2012, a total of 20 patients (11 male) with heterotaxy syndrome underwent biventricular repair (left atrial isomerism: 10 and right atrial isomerism: 10) in our center. Their median age at surgery was 40 (range: 3-108) months. Ten patients had dextrocardia. Eleven patients presented with bilateral superior vena cava, three with inferior vena cava (IVC) draining into left atrium, and six with IVC interruption with azygos or hemiazygos continuation. Anomalous pulmonary venous drainage was present in eight patients. One had a common atrium. Atrioventricular septal defect (AVSD) occurred in nine (complete AVSD in seven) patients. Eight patients had double outlet right ventricle (DORV), one had d-transposition of great arteries (d-TGA), and two had congenitally corrected transposition of the great arteries (CC-TGA). Prior palliative procedures included pulmonary artery banding in three patients and left modified Blalock-Taussig shunt in one patient. Complex intra-atrial baffle constructions were required in all patients to direct pulmonary and systemic venous inflow to the appropriate ventricle. Complete AVSDs were corrected using two-patch technique. Intraventricular tunnel repair was done for DORV. Combined atrial and arterial switch was required to rectify abnormal connections in a child with congenitally corrected transposition with normal pulmonary valve, while a Rastelli + Senning was needed in two children with CC-TGA with pulmonary atresia (n = 1) and double outlet of the right ventricle (n = 1).

RESULTS

Major early postoperative complications included intestinal gangrene in four patients for which they underwent bowel resection. Two of these patients could not be salvaged. One patient required coiling of aortopulmonary collateral for early postoperative pulmonary hemorrhage. Two patients needed a tracheostomy for prolonged mechanical ventilatory support. Five patients had a pacemaker implanted for complete heart block. There were no instances of atrial baffle stenosis. Median follow-up was 27 (range: 2-46) months. There was one late death secondary to pneumonia.

CONCLUSIONS

Satisfactory survival outcomes can be achieved in heterotaxy patients who undergo hemodynamically acceptable biventricular repair. Borderline ventricular hypoplasia and trivial atrioventricular valve regurgitation should not be considered as discouraging factors in anatomically suitable heterotaxy patients as it is possible to adopt a two-stage repair in such patients to achieve biventricular repair at a later stage. Anticipating a higher incidence of conduction problems and gut malrotation preemptively can help reduce the morbidity.

Defects in laterality with emphasis on heterotaxy syndromes with asplenia and polysplenia: an autopsy case series at a single institution

Heterotaxy is a rare disease with high morbidity and mortality. Controversy exists over how to classify these syndromes with most cases stratified into asplenia/polysplenia syndromes or right/left isomerism. In an effort to review comprehensively specific pheonotypes associated with heterotaxy syndromes, we reviewed published cases series, adopted a classification scheme based on spleen status, and evaluated autopsy cases retrospectively with abnormal laterality at our institution. We categorized 116 cases as situs inversus totalis, polysplenia, asplenia, and single right-sided spleen. Cardiovascular abnormalities occurred in 87.1% of polysplenia, 90.5% of asplenia, and all cases of single right-sided spleen. For polysplenia, 48.9% had bilateral bilobed lungs, 87% had right-sided stomach, 58.1% had midline symmetric liver, and 60.4% had malrotated intestines. For asplenia, 51.9% had bilateral trilobed lungs, 86.7% had right-sided stomach, 45.8% had symmetric liver, and 65.5% had malrotated intestines. Atrioventricular septal defects occurred in 91.2% of asplenia compared to 56.8% of polysplenia cases. Eight percent had pulmonary/aortic stenosis or atresia. Double outlet right ventricle was more common in polysplenia (32.6%) compared to asplenia (21.4%). Total anomalous systemic venous return was described in 55.6% of polysplenia and total anomalous pulmonary venous connections in 81% of asplenia cases. Greater than half of the cases had no heterotaxy diagnosis. Although, we found similar heterotaxy-associated characteristics, the frequencies differed from previous studies. We found great variation in how heterotaxy-associated defects were described, diagnosed, and reported. Although there are known associated characteristics with the polysplenia/asplenia syndromes, correct identification requires a standardized approach for diagnosis and reporting.