Catheter ablation of supraventricular tachycardia in patients with dextrocardia and situs inversus.

BACKGROUND: Dextrocardia with situs inversus is a rare cardiac positional anomaly. Catheter ablation procedures performed in this set of patients have not been sufficiently reported. METHODS: A total of 10 patients with dextrocardia and situs inversus who received catheter ablation for supraventricular tachycardia (SVT) were included from a cohort of over 20 000 cases of catheter ablation for SVT in three centers from 2005 to 2016. All patients underwent electrophysiologic study and catheter ablation of SVT. Ablation targets were selected based on different tachycardia mechanisms with the primary endpoint of noninduction of tachycardia. RESULTS: The average age was 32.4 ± 5.6 years. Congenitally corrected transposition of great arteries (TGA) with situs inversus and D-looping of the ventricles and aorta (congenitally corrected TGA {I,D,D}) was found in four patients, while the other six patients exhibited mirror-image dextrocardia {I,L,L}. The mechanisms of SVT were atrioventricular nodal reentrant tachycardia in four patients, atrioventricular reentrant tachycardia in three, typical atrial flutter in one, intra-atrial reentrant tachycardia in one, and focal atrial tachycardia in one. Immediate procedural success was achieved in 9 out of 10 patients with no procedural complications. During a follow-up period of 6.3 ± 3.5 years on average, all patients remained free from recurrent tachycardia. CONCLUSIONS: For patients with dextrocardia and situs inversus, catheter ablation of SVT is safe and feasible. Differences in catheter maneuver and fluroscopy projection, along with difficulties in distorted anatomy are major obstacles for successful ablation.

Atrioventricular Canal and Dextrocardia: A Case Report with Implications for Community-Based Providers.

Congenital heart defects (CHD) are the most common congenital malformation reported in the literature, with a global incidence of eight per every 1,000 live births. In the United States approximately 40,000 infants are born each year with a CHD. Of the infants diagnosed with a CHD, one in every four heart defects are life threatening in origin. Early identification and treatment of congenital heart lesions, beginning with a comprehensive physical assessment after birth, are critical. For infants delivered at community-based hospitals, the importance of the physical assessment, timing of diagnostic strategies, anticipatory planning, and interprofessional collaboration among referring and accepting centers cannot be understated. This article presents a rare case of an infant with atrioventricular canal complicated by dextrocardia. Embryology, pathophysiology, epidemiology, symptomology, cardiac assessment, diagnostics, treatment, and nursing strategies for facilitating transfer of care from community-based hospitals to tertiary medical centers are discussed.

Successful percutaneous coronary intervention for an in-stent chronic total occlusion in a patient with dextrocardia: a case report.

BACKGROUND: Percutaneous coronary interventions of chronic total occlusion represent one of the most challenging issues in interventional cardiology. A Caucasian patient with dextrocardia presented with an in-stent chronic total occluded right coronary artery, a constellation which has not been described previously in the literature. CASE PRESENTATION: A 69-year-old man with pre-known situs inversus totalis and a long history of coronary artery disease with multiple interventions and stent-implantations presented to our department suffering from episodes of chest pain under exercise. A coronary angiogram showed a completely occluded right coronary artery in the area of a drug-eluting stent which had been implanted eight years before. We found collaterals from the left coronary artery system and signs of calcification, so the lesion was classified as chronic total occlusion and the recanalization using an antegrade wire escalation technique successfully performed. CONCLUSION: This is the first reported case of an in-stent chronic total occlusion in situs inversus with dextrocardia. Our experience in this case demonstrates the feasibility of recanalization of in-stent chronic total occlusions even in the rare setting of this congenital cardiac malposition combined with severe coronary artery disease.

Comparing levocardia and dextrocardia in fetuses with heterotaxy syndrome: prenatal features, clinical significance and outcomes.

BACKGROUND: To investigate the differences in cardiovascular disease, extracardiac anomalies and outcomes between fetuses with levocardia and dextrocardia. METHODS: Clinical demographics, prenatal features, postnatal characteristics and the outcomes of fetuses with levocardia or dextrocardia were recorded and analyzed. RESULTS: Sixty-five fetuses with dextrocardia and thirty-eight fetuses with levocardia were enrolled. Right ventricle outlet obstruction, atrioventricular septal defect and intestinal malrotation were common in both groups. Univentricular physiology, transposition of the great arteries and esophageal atresia were more frequent in fetuses with levocardia, whereas abnormal pulmonary venous connection, double outlet of right ventricle, left ventricle outlet obstruction and brain abnormalities were more frequent in the dextrocardia group. The accuracy of evaluating cardiac malformations was high, but the sensitivity in assessing extracardiac abnormalities was low. CONCLUSIONS: Although the disorders have certain overlapping features, there are several differences between fetuses with levocardia and dextrocardia. These findings might improve patient counseling and perinatal management.

Dextrocardia in Adults with Congenital Heart Disease.

BACKGROUND/OBJECTIVES: Dextrocardia is rare in the general population, and may be associated with significant additional cardiac malformations. We aimed to identify the prevalence and patterns of additional cardiac defects, as well as the associated long-term morbidity and mortality, in adult patients with dextrocardia, in a specialised Adult Congenital Heart Disease (ACHD) service. METHODS: A retrospective study of patients with dextrocardia managed by our tertiary ACHD service, since January 2000, was performed. Medical records were reviewed and the National Death Index was consulted to confirm survival status. RESULTS: Of 3698 adults in our ACHD Service, 19 (0.5%) had dextrocardia. Mean follow-up duration was 7±7.5 years. The mean age at last review was 36.8±10.5 years (range 20-63 years). Situs was solitus in 14 (74%) and inversus in five (26%). Eleven patients (58%) had functional single ventricles, of whom five had atrioventricular (AV)-ventriculoarterial (VA) discordance and two had VA discordance only. Four patients with two ventricles had AV-VA discordance. All patients had at least one additional cardiac malformation. Fourteen patients (74%) required surgical intervention. Eleven patients (58%) underwent a Fontan-type operation. Five patients (26%) required ablation procedures for arrhythmia. One patient had infective endocarditis and two deaths occurred, both in patients who also had AV-VA discordance. CONCLUSION: Dextrocardia remains a rare finding in adults, even in a highly select group of patients with known congenital heart disease. Those with associated congenital heart abnormalities are likely to have complex lesions, which may require multiple surgical and medical interventions. Despite this, our series demonstrated that patients surviving to adulthood and then managed in an ACHD centre may have good medium-term survival.

CLINICAL CASE OF THE MONTH: A Review of Situs Inversus and Dextrocardia.

A 21-year-old woman at 25 weeks gestation presented to the emergency department with chief complaints of decreased appetite for one week, fever, runny and stuffy nose, and generalized muscle pains.

Transhepatic approach to create stent fenestration in the extracardiac Fontan conduit in a child with dextrocardia and interrupted inferior vena cava with azygos continuation.

Plastic bronchitis is a rare life-threatening complication of Fontan operation. When medical treatment is ineffective in the setting of high systemic venous pressures, Fontan fenestration may be considered to decompress venous pressures and improve cardiac output by creation of the right-to-left shunting. However, transcatheter approach can be difficult in patients with complex venous anatomy. We report a 4-year-old girl born with hypoplastic left ventricle and heterotaxy syndrome, who developed plastic bronchitis following extracardiac Fontan procedure. Her venous anatomy was complex with dextrocardia and interrupted inferior vena cava with azygos continuation. Stent fenestration was successfully performed via transhepatic approach, which was selected based on the anatomical relationship (between extracardiac conduit, left atrium, and hepatic veins) delineated by pre-catheterization cardiac MRI. Simultaneous transesophageal echocardiography guided the intervention. Her plastic bronchitis improved significantly in 3 months but slowly progressed after the stent fenestration. At her 8-month follow-up, stent fenestration remains open and she is currently under heart transplantation evaluation due to persistent plastic bronchitis. Treatment of plastic bronchitis can be undertaken with Fontan fenestration, with pre-procedural MRI playing an essential role in patients with complex venous anatomy.

Atrial tachycardia originating from the atrial septum in a patient with dextrocardia and complex structural heart disease.

We report a case with dextrocardia, corrected transposition of the great arteries. He also had an atrial septum defect (ASD) with patch repair. Activation map showed a centrifugal activation from a focal origin on the systemic lower left atrial ASD patch. Ablation of the origin can terminate the atrial tachycardia.

A mouse model of conduction system patterning abnormalities in heterotaxy syndrome.

Duplication or absence of parts of the specialized cardiac conduction system in patients with heterotaxy syndrome causes significant clinical disease, but the mechanistic basis by which embryonic disruption of left-right patterning alters conduction system patterning in these patients is not well understood. We sought to determine whether a mouse model of X-linked human heterotaxy recapitulates conduction system abnormalities identified in patients with heterotaxy. Cardiac structure and conduction system patterning were evaluated in Zic3 null embryos from e9.5 to e16.5 using genetic and molecular methods. Severe structural abnormalities involving atrial, ventricular, and conotruncal development were associated with a spectrum of disorganized and ambiguous arrangements throughout the conduction system, including the appearance of duplicated structures. The severity and location of conduction system abnormalities correlated with the severity and location of associated structural heart disease and were identifiable at the earliest stages examined. The Zic3 mouse model provides a novel tool to dissect the mechanistic underpinnings of conduction system patterning and dysfunction and its relationship to cardiovascular malformations, making it a promising model to improve understanding and risk assessment in the clinical arena.

A case report of late-onset symptoms of erythrocytosis in univentricular dextrocardia.

RATIONALE: Univentricular dextrocardia is a rare congenital heart disease that usually presents cyanotic manifestations from childhood. Due to the sustained dysfunction of blood oxygenation, it is very difficult to keep an asymptomatic survival. Herein, we described an interesting case of univentricular dextrocardia who suffered from initial symptoms in his middle age. PATIENT CONCERNS: A 54-year-old male patient with numbness and tingling of limbs was admitted to hospital due to the secondary manifestations of congenital heart disease. DIAGNOSIS: The patient was diagnosed as univentricular dextrocardia with pulmonary hypertension and secondary erythrocytosis based on computed tomography (CT) scan, echocardiography, and laboratory examinations. INTERVENTIONS: Intravenous hydration therapy with normal saline successfully eliminated his hyperviscosity associated symptoms. In view of socio-economic reasons, this patient refused surgical evaluation and further medical interventions. OUTCOMES: During 18-month follow up, he received no drug except for regular water intake. Fortunately, his life quality was satisfactory, and no other symptoms emerged except for mild numbness of limbs. LESSONS: In univentricular dextrocardia, it is possible to keep a long-term asymptomatic period due to the slow progress of pathophysiology. In this population, regular cardiac function evaluation and avoiding dehydration may help improve the quality of life.

Transvenous cardiac resynchronization therapy in complex congenital heart diseases: dextrocardia with transposition of the great arteries after Mustard operation.

Cardiac resynchronization therapy revealed first promising results in patients with a congenital heart disease and a systemic right ventricle. Contrast-enhanced magnetic resonance imaging showed accessibility of the coronary sinus in an 18-year-old male patient with mirror dextrocardia, d-transposition of the great arteries and ventricular septal defect (VSD) after Mustard operation and VSD patch closure. In literatures, transvenous lead placement is discussed in this anatomical setting, with opposed position of the ventricular leads and reliable lead characteristics.

Focal atrial fibrillation in dextrocardia.

A 49-year-old woman with dextrocardia and situs inversus underwent catheter ablation of paroxysmal atrial fibrillation (AF). During the electrophysiologic study, AF triggered by frequent premature atrial contractions (PACs) with a short coupling interval exhibiting a "P on T" pattern occurred. Pulmonary vein mapping revealed that those PACs originated from right-sided (anatomic left) or left-sided (anatomic right) pulmonary veins. In this case with mirror-image dextrocardia, the P-wave morphologies in leads I and aVL and the II/III ratio of the P-wave amplitude were helpful for predicting a right- or left-sided pulmonary vein origin.

A retrospective review of right-sided hearts at a South African tertiary hospital.

BACKGROUND: A right-sided heart (RSH) has three main causes: dextrocardia, dextroposition and dextroversion. It may be associated with cardiac malformation, extra-cardiac abnormalities and adverse patient outcomes. The aim of this study was to determine the prevalence, demographics, associated cardiac malformations (ACM) and outcome of paediatric patients diagnosed with a RSH at a South African tertiary hospital. METHODS: A retrospective review was performed over a 22-year period. RESULTS: RSH comprised 1% of the paediatric cardiology referrals. Dextrocardia was the most frequent cause (58.1%) and the majority of these patients had ACM (81.5%). More than a third (40.9%) were diagnosed with dextroposition, secondary to extra-cardiac factors. Dextroversion was the least common cause (1.1%). Over a quarter of all patients were confirmed dead at the time of the study; most had been diagnosed with dextrocardia. Two-thirds of the patients were lost to follow up. CONCLUSIONS: A RSH is an unusual occurrence. Dextrocardia, the most common cause, is frequently associated with ACM and extra-cardiac abnormalities. It is therefore important to timeously elucidate the cause of a RSH.

Partition of Common Atrioventricular Valve in a Patient With Dextrocardia and Univentricular Circulation.

Long-term outcomes in children with atrioventricular septal defect (AVSD) and univentricular palliation are of concern, with <60% survival at 25 years.1 Common atrioventricular valves (AVV) often become insufficient in patients with univentricular physiology, leading to heart failure.1,2 We have recently observed that outcomes of children with AVSD who reach Fontan circulation are not as bad as previously thought, provided that the AVV remains competent.1 Common AVV surgery is associated with substantial mortality and reoperation rates.3 Although successful AVV repair is associated with better survival and freedom from reoperation, good quality repair is difficult to achieve in univentricular circulation,3 especially in patients with dextrocardia.4 Herein, we report a patient with unbalanced AVSD and dextrocardia who underwent AVV repair using the "polytetrafluoroethylene (Gore-Tex, W.L. Gore & Associates, Flagstaff, AZ) bridge" technique5 with excellent early outcome.

Quantitation in Dextrocardia on myocardial perfusion imaging: how to perform quantitative analysis using Cedars-Sinai software.

Dextrocardia, although a rare cardiac abnormality, carries the same risk for cardiac events as other people. SPECT Myocardial perfusion imaging is a potentially helpful diagnostic tool in patients with dextrocardia. Because of swapping of lateral and septal walls on SPECT slices, although visual analysis is possible, quantitation is substantially limited. Here, we introduce a simple practical method to make quantitative analysis feasible and accurate.

Severe aortic stenosis in dextrocardia with situs invertus and anomalous single coronary ostium treated with transcatheter aortic valve replacement.

Dextrocardia with situs inversus presents a unique anatomy with right-sided vascular system that may be associated with a number of additional cardiac and vascular malformations. A rare association is the presence of a single coronary artery ostium. To our knowledge, this is the first reported case of transcatheter aortic valve replacement using Edwards SAPIEN S3 valve in Dextrocardia patient with single coronary artery take off.