Exploring new frontiers: a rare case of catheter ablation for persistent atrial fibrillation in a patient with cor triatriatum sinister guided by intracardiac echocardiography.

BACKGROUND: Cor triatriatum sinister (CTS) is an uncommon congenital cardiac anomaly. Atrial fibrillation (AF) is commonly the initial symptom in patients with CTS, occurring in approximately 32% of the cases. The complexity of performing AF catheter ablation, particularly in cases with persistent AF, increases in patients with CTS due to its unique structural challenges. CASE PRESENTATION: We report the treatment course of a 60-year-old male patient diagnosed with CTS, who underwent catheter ablation of drug-refractory, persistent AF. The complex anatomical structure of the condition made catheter ablation of AF challenging. To navigate these challenges, we performed comprehensive assessments using transthoracic echocardiography and transesophageal echocardiography, along with cardiac computed tomography angiography, prior to treatment initiation. The intricate anatomy of CTS was further clarified during the procedure via intracardiac echocardiography (ICE). Additionally, the complexity of catheter manipulation was further reduced with the aid of the VIZIGO sheath and the vein of Marshall ethanol infusion to achieve effective mitral isthmus blockage, thereby circumventing the impact of the CTS membrane. CONCLUSIONS: This case underscores the complexity and potential of advanced ablation techniques in managing cardiac arrhythmias associated with unusual cardiac anatomies. During the procedure, ICE facilitated detailed modeling of the left atrium, including the membranous structure and its openings, thus providing a clearer understanding of CTS. It is noteworthy that the membrane within the CTS may serve as a potential substrate for arrhythmias, which warrants further validation through larger sample studies.

Labyrinthine cor triatriatum sinister in fetal hypoplastic left heart syndrome is associated with poor outcomes.

OBJECTIVES: A subset of hypoplastic-left-heart-syndrome (HLHS) fetuses have a complex cor-triatriatum sinister that we named "labyrinthine-cor (L-cor)". We sought to determine the prevalence of L-cor in HLHS fetuses and hypothesized that it is associated with increased mortality. METHODS: This single-center retrospective cohort study included all HLHS fetuses from January 2010-December 2020. Fetuses with other hypoplastic-left-heart variants, inadequate images, lack of follow-up and fetal atrial-septal interventions were excluded. RAS was defined as the ratio of pulmonary-vein forward-to-reverse velocity-time-integral (VTI) ≤ 5 and severe-RAS defined as VTI-ratio <3. Kaplan-Meier survival-analysis was performed for the primary outcome of transplant-free survival for 62 weeks after gestational-age of 30 weeks (∼1 year). RESULTS: Of the 156 consecutive fetuses with HLHS, 11 (7.7%) had L-cor and 8/11 (72.7%) of these had RAS. When compared to HLHS-RAS without L-cor, fetuses with HLHS-RAS and L-cor were less likely to survive to 28 days (87% vs. 62.5%, p = 0.017) and to 1 year (69.6% vs. 25%, p = 0.029). When comparing by survival analysis, fetuses with severe-RAS with L-cor had lower survival compared severe-RAS without L-cor (p = 0.020). CONCLUSION: L-cor in fetal HLHS is associated with increased mortality. Recognition of this finding is important for prognostication and atrial-septal-intervention planning.

Obstructed Supramitral Inflow: Cor Triatriatum Sinister Presentation in Adulthood.

Cor triatriatum is a rare congenital heart defect that occurs when a fibromuscular membrane divides the atrium into two chambers, which may impair blood flow to the ventricle. When it does, the symptoms usually manifest during infancy or early childhood. In this E-challenge, though, the case of a 40-year-old man is reviewed whose symptoms of shortness of breath progressed over the years and were attributed to the diminished mitral valve inflow due to the restricted cor triatriatum sinister associated with pulmonary hypertension, tachycardia-bradycardia syndrome, and atrial fibrillation. Despite routine preoperative evaluation, intraoperative transesophageal echocardiography was used to more accurately evaluate cor triatriatum sinister's morphology, hemodynamic significance, and associated anomalies.

An extreme case of cor triatriatum mimicking hypoplastic left heart syndrome and combined pulmonary vein stenosis.

A 65-day-old girl presented to the emergency room with lethargy, requiring emergency venoarterial extracorporeal membrane oxygenation for refractory cardiogenic shock. Initially, hypoplastic left heart syndrome was suspected. However, cor triatriatum with a pinpoint opening on the membrane was diagnosed based on a detailed echocardiographic examination. After membrane resection, the left heart size was restored. However, follow-up echocardiography performed 4 months later showed occlusion of both upper pulmonary veins and stenosis in both lower pulmonary veins. Hybrid balloon angioplasty was performed in all pulmonary veins, and stents were inserted into the right upper and lower pulmonary veins. Despite repeated balloon angioplasty, all pulmonary vein stenosis progressed over 6 months and the patient expired while waiting for a heart-lung transplant. Even after successful repair of cor triatriatum, short-term close follow-up is required for detecting the development of pulmonary vein stenosis.

Cor triatriatum sinister with dextrocardia in association with ostium secundum atrial septal defect, subpulmonary ventricular septal defect and bicuspid pulmonary valve in a pig.

Necropsy of a 52-day-old Camborough pig revealed numerous cardiac malformations. The positional relationship of the atria, ventricles and great vessels was a mirror image type (I, L and L): inverted arrangement of the atria, with a left-sided right atrium and right-sided left atrium (situs inversus); inverted arrangement of the ventricles, with a left-sided morphological right ventricle and right-sided morphological left ventricle (L-loop); and aortic valve to the front left relative to the pulmonary valve (L-malposed). The major malformations included an ostium secundum atrial septal defect, cor triatriatum sinister (CTS), a subpulmonary ventricular septal defect and a bicuspid pulmonary valve. Histological examination revealed myocyte hypertrophy, focal myocardial necrosis and calcification in the left morphological right ventricle of the heart. To the best of our knowledge, this is the first report of CTS in pigs. Although the individual malformations found in the present case are not unique, an unusual combination of these cardiac malformations has not been described in animals.

Hidden problems in a case of atrial fibrillation.

Atrial fibrillation (AF) is the most common cardiac arrhythmia. However, the relation between congenital heart defects and the predisposition to AF is not fully understood. A 65-year-old male was admitted into the emergency department due to progressive dyspnea, orthopnea, palpitations, and edema. Transthoracic echocardiogram showed bi-atrial enlargement and dysplasia of the mitral leaflets with severe mitral regurgitation. Also, a membrane was noted in the LA, dividing the chamber into two parts, suggestive of cor triatriatum sinister. Coronary computed tomography angiography demonstrated a soft tissue septum in the left atrium. Multimodal evaluation is of vital importance for a complete approach, since, detected in time, it has an excellent prognosis.

Corrected Transposition of Great Arteries with Cor Triatriatum and Atrial Septal Defect-Case Report.

A 37-year-old male patient with corrected transposition of great arteries (ccTGA) with cor triatriatum sinister (CTS), left superior vena cava, and atrial septal defects is reported in our case. None of these impacted the patient's growth or development, nor daily work until age 33. Later, the patient developed symptoms of obvious impaired heart function, which improved after medical treatment. However, the symptoms reappeared and gradually worsened two years later, and we decided to treat it with surgery. In this case, we selected tricuspid mechanical valve replacement, cor triatriatum correction, and atrial septal defect repair. During the follow-up of five years, the patient had no obvious symptoms, ECG did not change significantly from five years ago, and the cardiac color Doppler ultrasound showed RVEF 0.51.

Long-term palliation of right-sided congestive heart failure after stenting a recurrent cor triatriatum dexter in a 10½-year-old pug.

A 10½-year-old, male neutered, pug presented with increasing ascites over two months. Echocardiography revealed cor triatriatum dexter with no concurrent cardiovascular anomalies, subsequently confirmed by computed tomography angiography. Balloon dilation of the perforated intra-atrial membrane under fluoroscopic guidance resulted in the transient resolution of all clinical abnormalities, but six months later stenosis and ascites recurred. After repeated balloon dilation, a stent was placed across the membrane. The dog remains asymptomatic fourteen months after the second procedure. One noteworthy feature of this case is the onset of congestive heart failure due to a congenital defect only at more than 10 years of age.

Triatriatum sinistrum em adulto assintomático: relato de caso / Cor triatriatum sinistrum in an asymptomatic adult: a case report

Cor triatriatum é um anomalia cardíaca congênita rara frequentemente diagnosticada na primeira infância. Este estudo de caso apresenta um adulto com um achado acidental de cor triatriatum sinistrum. Com base na apresentação clínica, o paciente foi tratado de forma conservadora. São apresentados achados de imagens ecocardiográficas de cor triatriatum sinistrum deste paciente juntamente de revisão narrativa da literatura sobre essa doença.(AU)

Cor triatriatum is a rare congenital heart anomaly often diagnosed in early childhood. This case study features an adult with an incidental finding of cor triatriatum sinistrum. Based on the clinical presentation, the patient was treated conservatively. Cor triatriatum sinistrum echocardiographic image findings of this patient are presented along with a narrative review of the literature about this disease. (AU)

Catheter ablation of atrial fibrillation in patients with cor triatriatum sinister; case series and review of literature.

INTRODUCTION: Cor triatriatum sinister (CTS) is a rare congenital heart defect characterized by fibromuscular septation of the left atrium associated with atrial fibrillation (AF). The incidence of hemodynamically insignificant CTS in the AF ablation population and effect on ablation success are not known. Furthermore, little is known about the potential effect of CTS on arrhythmogenic substrate. OBJECTIVE: We define the incidence of hemodynamically insignificant CTS in patients undergoing AF ablation with RF and cryoballoon ablation, the technical challenges created by the left atrial partitioning, and the potentially arrhythmogenic effects of the membrane. We also review the literature of CA in patients with CTS. METHODS: First-time AF ablation cases at our institution over a 10-year period were screened to identify patients with CTS. Retrospective review was performed to obtain clinical characteristics and ablation data. RESULTS: Of the 3953 consecutive patients undergoing initial AF ablation during the study period, four patients (0.10%) had CTS. Ablation was successful acutely in all patients. One patient had recurrent AF and required repeat ablation for a single procedure success rate of 75% and multi-procedure success rate of 100%. The CTS membrane was associated with low voltage zones in the two patients in whom it was measured and with substrate for macro-reentrant atrial tachycardia in one of these patients. CONCLUSION: The incidence of hemodynamically insignificant CTS in patients undergoing CA for AF is very low, but does not serve as a significant barrier to successful ablation as long as directed access to the superoposterior chamber is obtained.

Shear Stress Causing Hemolytic Anemia and Congestive Heart Failure as an Initial Presentation of Cor Triatriatum in an Infant.

Among congenital cardiac defects, cor triatriatum sinistrum is a rare formation of 3 distinct atrial chambers in the heart. Depending on the size of the defect in the membranous septum, the symptoms can range from asymptomatic to severe pulmonary hypertension. Individuals can go years, sometimes to the second and third decades of life, before presenting with symptoms. Although it is well known to be associated with pulmonary veno-occlusive disease, the association with hemolytic anemia is much less well known. Identifying the subtle signs and symptoms of cor triatriatum in the emergency department can save a life. Here, we present the case of a 6-month-old infant with hemolytic anemia in the setting of right-sided congestive heart failure leading to the diagnosis of cor triatriatum. Anemia developed secondary to shearing stress caused by the heart defect itself. Complete resolution of symptoms occurred status post septectomy and repair of the defect.

Cor Triatriatum Sinistrum: A rare disease with a common presentation.

Cor triatriatum sinistrum (CTS) is a rare congenital cardiac anomaly characterised by an abnormal septum within the left atrium impairing blood flow to the left ventricle. We report the case of a two-month-old male infant who presented with symptoms of heart failure since the age of two weeks. He was admitted to a local hospital and was managed with antibiotics because of the impression of pneumonia. Due to persistent unresolved tachypnoea and tachycardia, he was referred to Sultan Qaboos University Hospital, Muscat, Oman, in 2019 for cardiac evaluation which confirmed a diagnosis of isolated CTS with severe stenosis and pulmonary hypertension. He underwent an urgent surgical excision of the membrane with uneventful recovery.

Adult Obstructive Cor Triatriatum with Severe Mitral Regurgitation: A Case Report.

Adult cor triatriatum sinister associated with severe mitral regurgitation is extremely rare. As these obstructive cor triatriatum feature hemodynamics that mimic mitral stenosis, a pressure load is theoretically generated only on the left atrial proximal chamber, and therefore the left ventricle is less likely to suffer volume loading. Here, we report a surgical case with such rare hemodynamics. A 22-year-old man with obstructive cor triatriatum and severe mitral regurgitation received an anomalous membrane excision and mitral annuloplasty. An abnormal membrane with an orifice 7 mm in size was completely resected while a grossly dilated mitral annulus was repaired via annuloplasty ring. Mitral regurgitation was controlled well, and the postoperative course was uneventful. Even with obstructive cor triatriatum, severe mitral annular dilatation and subsequent left ventricular dilatation may occur, causing the progressive heart failure encountered in this case.

Successful radiofrequency perforation and balloon decompression of cor triatriatum sinister using novel technique, a case series.

Cor triatriatum sinister (CTS) is a rare congenital cardiac anomaly representing <0.1% of all congenital cardiac malformations. It is characterized by the presence of a left atrial (LA) membrane that leads to left ventricular inflow obstruction. Uncorrected, obstructed CTS may have significant sequelae such as pulmonary hypertension or arrhythmias. Transcatheter balloon decompression has been described as a successful alternative to surgical resection of the obstructing membrane. Our review of the literature revealed no reported cases utilizing radiofrequency (RF) energy to perforate the CTS membrane prior to balloon decompression. This manuscript describes two patients with CTS who were treated successfully with a transcatheter technique using RF energy to perforate the obstructing membrane prior to balloon angioplasty and decompression of the LA.

Cor Triatriatum Can Coexist With Common Pulmonary Venous Atresia.

Surgical treatment was very urgently carried out in an extremely cyanotic newborn with common pulmonary venous atresia. The diagnosis was confirmed during the procedure, and the common venous chamber was anastomosed to the left atrium through a transverse incision onto the right and the left atria. Unfortunately, pulmonary hypertension persisted during the postoperative course and even got worse gradually. Computed tomography eventually illustrated residual cor triatriatum. The initial atriotomy had been entirely above the diaphragm within the left atrium. Consequently, the abnormal structure had been overlooked. The patient is doing well 1 month after the surgical revision. Pulmonary hypertension disappeared.

Psuedo-Cor Triatriatum in an Elderly Patient With Dyspnea of Exertion: An Undescribed Condition Characterized by 3-Dimensional Transesophageal Echocardiography.

A 66-year-old gentleman with no prior cardiac history presented with dyspnea on exertion and chest pain for 1 month. His workup included a transthoracic echocardiogram, which demonstrated findings suggestive of cor triatriatum (C-TAT) with uncertain degree of hemodynamic obstruction. In addition, mild left ventricular systolic dysfunction and segmental wall motion abnormalities suggestive of coronary artery disease were noted. The patient then underwent transesophageal echocardiography (TEE) to define better the structural characteristics and hemodynamic significance of the C-TAT, left and right heart catheterization to assess pressure gradients between the upper and lower left atrial chambers by simultaneous measurement of pulmonary capillary wedge and left ventricular end-diastolic pressures, and coronary angiography. Multiplane 2-dimensional TEE demonstrated an atrial membrane extending from the inferior portion of the interatrial septum to the superior aspect of the lateral atrial wall. This membrane exhibited a medial large oval opening with bidirectional flow and a ≤2 mm Hg gradient. Three-dimensional TEE imaging re-demonstrated this obliquely oriented membrane; however, of most importance, it revealed that the membrane divided the atria into a medial funnel and C-shaped cavity with a large distal oval shape opening and an even larger lateral atrial cavity. These findings were inconsistent with a true C-TAT and rather demonstrated what we defined as a pseudo-C-TAT membrane. Simultaneous right and left heart catheterization confirmed a minimal gradient of 3 to 5 mm Hg and coronary angiography demonstrated severe 3-vessel coronary disease as the primary cause of the patient's clinical syndrome.