Atrial septum anatomy as a predictor of ischemic neurological episodes in patients with a patent foramen ovale.

BACKGROUND: The correlation between atrial septum anatomy and the risk of ischemic neurological events remains underexplored. AIMS: This study aimed to examine both the functional and anatomical attributes of the atrial septum and identify predictors of stroke and/or transient ischemic attack (TIA) in patients diagnosed with patent foramen ovale (PFO). METHODS: A total of 155 patients diagnosed with PFO, with a cardiological cause of neurological events, were enrolled. Transesophageal echocardiography was utilized to assess the anatomy of the PFO canal, size of the right-to-left shunt, thickness of the primary and secondary atrial septum, presence of atrial septum aneurysm, and anatomical structures of the right atrium. RESULTS: Regression analysis showed that factors such as female sex, hypercholesterolemia, PFO canal width, and a large right-to-left shunt were significantly associated with stroke and/or TIA. Receiver operating characteristic analysis indicated that the width of the PFO canal holds a relatively weak, although significant predictive, value for ischemic neurological episodes (area under the curve = 0.7; P = 0.002). A PFO canal width of 4 mm was associated with 70% sensitivity and 55% specificity for predicting stroke and/or TIA. CONCLUSIONS: The atrial septum's anatomy, especially the dimensions of the PFO canal and the magnitude of the right-to-left shunt, combined with specific demographic and clinical factors, are linked to ischemic neurological incidents in PFO patients.

Does Atrial Septal Anatomy Still Matter in the Etiological Evaluation of Ischemic Stroke Beyond the Age of 60?

BACKGROUND: Patent foramen ovale (PFO) is causally associated with stroke in some patients younger than 60 years, especially when it is large or associated with an atrial septal aneurysm (ASA). After 60 years of age, this association is less well understood. We assessed the relationships between detailed atrial septal anatomy and the cryptogenic nature of stroke in this population. METHODS AND RESULTS: We reviewed all patients aged 60 to 80 years admitted to our stroke center for ischemic stroke who underwent contrast echocardiography between 2016 and 2021. The atherosclerosis, small-vessel disease, cardiac pathology, other causes, and dissection (ASCOD) classification was used to reevaluate the etiological workup. Associations between cryptogenic stroke and (1) PFO presence or (2) categories of PFO anatomy (nonlarge PFO without ASA, nonlarge PFO with ASA, large PFO without ASA, and large PFO with ASA) were assessed using logistic regression. Among 533 patients (median National Institutes of Health Stroke Scale score=1), PFO was present in 152 (prevalence, 28.5% [95% CI, 24.9-32.5]). Compared with noncryptogenic stroke, cryptogenic stroke (n=218) was associated with PFO presence (44.5% versus 17.5%; P<0.0001). Among patients with a PFO, septal anatomy categories were associated with cryptogenic stroke (P=0.02), with a strong association for patients with both large PFO and ASA (38.1% versus 14.5%, P=0.002). CONCLUSIONS: PFO presence remains strongly associated with cryptogenic stroke between 60 and 80 years of age. Large PFO, ASA, and their association were strongly associated with cryptogenic stroke in this age group. Our results support performing contrast echocardiography even after 60 years of age, although the optimal secondary prevention therapy in this population remains to be determined in randomized trials.

Ignored Role of Paroxysmal Atrial Fibrillation in the Pathophysiology of Cryptogenic Stroke in Patients with Patent Foramen Ovale and Atrial Septal Aneurysm.

The association between cryptogenic stroke (CS) and patent foramen ovale (PFO) with or without atrial septal aneurysm (ASA) has been a debate for decades in terms of pathophysiologic processes and clinical courses. This issue has become more interesting and complex, because of the concerns associating the CS with so-called normal variant pathologies of interatrial septum, namely ASA and PFO. While there is an anatomical pathology in the interatrial septum, namely PFO and ASA, the embolic source of stroke is not clearly defined. Moreover, in patients with PFO and CS, the risk of recurrent stroke has also been associated with other PFOunrelated factors, such as hyperlipidemia, body mass index, diabetes mellitus, and hypertension, leading to the difficulty in understanding the pathophysiologic mechanism of CS in patients with PFO and/or ASA. Theoretically, the embolic source of cryptogenic stroke in which PFO and/or ASA has been involved can be categorized into three different anatomical locations, namely PFO tissue and/or ASA tissue itself, right or left atrial chambers, and venous vascular territory distal to the right atrium, i.e., inferior vena cava and lower extremity venous system. However, the possible role of paroxysmal atrial fibrillation associated with PFO and/or ASA as a source of cryptogenic stroke has never been mentioned clearly in the literature. This review aims to explain the association of cryptogenic stroke with PFO and/or ASA in a comprehensive manner, including anatomical, clinical, and mechanistic aspects. The potential role of paroxysmal atrial fibrillation and its contribution to clinical course have been also discussed in a hypothetical manner to elucidate the pathophysiology of CS and support further treatment modalities.

Stent Implantation Across the Atrial Flow Regulator Device.

The Atrial Flow Regulator (AFR) is a self-expandable double-disc device with a central fenestration, intended to maintain a calibrated communication across the interatrial septum. We reported for the first time a stent implantation across an AFR device in an adolescent born with complex congenital heart disease with duct-dependent systemic circulation and severe combined pulmonary hypertension.

Papillary fibroelastoma originating from the atrial septum touching the mitral valve leading to infective endocarditis: a case report.

BACKGROUND: Cardiac papillary fibroelastoma is a rare benign tumor, which is often mistaken for a vegetation. Predominantly asymptomatic, it can cause life-threatening complications. Although rare, mobile papillary fibroelastoma movement between affected valves may hamper valve closure and damage the valve, leading to valvular regurgitation. Endothelial damage increases the risk of developing infective endocarditis. We report a rare case of a highly mobile papillary fibroelastoma originating from the atrial septum touching the mitral valve, leading to mitral regurgitation and, eventually, infective endocarditis. CASE PRESENTATION: A 26-year-old woman with suspected infective endocarditis was referred to us from a previous hospital after having experienced intermittent fever for a month. Before the fever, she had been experiencing exertional dyspnea. In addition, she had undergone a cesarean section two weeks before this admission. A transthoracic echocardiogram showed a mobile mass originating from the atrial septum touching the mitral valve with severe mitral regurgitation. Computed tomography revealed an occluded right profunda femoris artery with an embolus. Infective endocarditis associated with a mobile vegetation with high embolic risk was diagnosed, and urgent surgery was performed. Following the surgery, examinations revealed papillary fibroelastoma originating from the atrial septum and infective endocarditis of the mitral valve. The histopathological examination confirmed that a mass initially thought to be a mobile vegetation was a papillary fibroelastoma. The postoperative course was uneventful except for pericarditis. There has been no recurrence of infective endocarditis or papillary fibroelastoma. CONCLUSIONS: The highly mobile papillary fibroelastoma was thought to have caused both chronic mitral regurgitation and infective endocarditis. Mobile papillary fibroelastomas can cause endothelial damage to nearby valves and predispose patients to infective endocarditis.

Video assisted thorascopic assisted correction of left partial anomalous pulmonary venous connection: one case report.

INTRODUCTION: The left partial anomalous pulmonary vein connection is a rare congenital heart disease, especially with intact atrial septum. Now we reported a case of the left superior pulmonary vein drainage to left innominate vein through a vertical vein, and corrected with video assisted thoracoscopy. CASE PRESENTATION: A-59-years old man diagnosed left anomalous partial pulmonary vein connection with presentation of short breathiness and palpation, and diagnosed with computer tomography pulmonary angiography. The operation was carried out under video assisted thoracoscopy with one manipulation incision and one observational incision, the vertical vein was dissected and anastomosis with left atrial appendage. The patients recovered smoothly and postoperative CTPA showed anastomosis ostium was unobstructed. CONCLUSION: The left lateral thoracotomy and video assisted thoracoscopic surgery is a feasible for correction of left PAPVC with intact interatrial septum without using CPB.

Interatrial Septum Stenting for Hypoplastic Left Heart Syndrome in Ex Utero Intrapartum Therapy.

Patients with hypoplastic left heart syndrome (HLHS) with intact atrial septum have an increased mortality rate. This presentation occurs in 6% to 10% of cases. We present a patient with fetal diagnosis of HLHS with restrictive atrial septum. We performed a cesarean section at 37 weeks of gestation, and under ex utero intrapartum treatment proceeded with a median sternotomy and transatrial stenting for left atrial decompression due to findings of intact atrial septum on the fetal echocardiogram performed during the procedure. Subsequently, the patient underwent hybrid stage I palliation followed by a comprehensive stage II procedure at five months of age, but unfortunately died from postoperative complications.

High-resolution mapping of the circuit of typical atrioventricular nodal reentrant tachycardia.

BACKGROUND: Recent anatomic and electrophysiologic evidence has provided new insight into the anatomic substrate. Previous reports on electroanatomic mapping (EAM) of the circuit of atrioventricular nodal reentrant tachycardia (AVNRT) have been limited by mapping only the triangle of Koch on the right side of the septum and by the use of conventional mapping tools. The objectives are to obtain comprehensive high-resolution mapping of typical AVNRT and to investigate the role of the atrioventricular ring tissues in the circuit. METHODS: We employed EAM with the use of novel modules and algorithms for studying typical AVNRT from the right and the left sides of the septum. RESULTS: We performed extensive mapping of both the atrial septum and the septal vestibule of the tricuspid valve during typical AVNRT in 9 (6 females) patients, aged 49.6 ± 12.1 years. In two of these, left septal mapping was also obtained through the aorta. The earliest initial activation was variable, emanating from the superior or medial septum. The impulse consistently appeared below the orifice of the coronary sinus, at the site where its inferoanterior margin merged with the septal vestibule of the tricuspid valve at its entrance to the right atrium. It then returned to the initial activation site, presumably through the septal vestibular myocardium. The left septal activation area corresponded to that recorded on the right side. CONCLUSIONS: Typical AVNRT uses a circuit confined within the pyramid of Koch from the AV node to the septal isthmus, involving the myocardial walls of the pyramidal space.

Low-cost prototyping of nitinol wires/frames using polymeric cores and sacrificial fixtures with application in individualized frames anchoring through the atrial septum.

Self-expanding frames for minimally invasive implants are typically made from nitinol wires and are heat treated to maintain the desired shapes. In the process of heat treatment, nitinol structures are placed in a high-temperature oven, while they are confined by a fixture. During this process, nitinol exerts a high amount of force. Accordingly, a fixture requires high mechanical strength and temperature resistance; this is why fixtures are typically made from metals. The use of metal fixture also increases the turnaround time and cost. However, accelerating this process is beneficial in many applications, such as rapid development of medical implants that are patient-specific. Inspired by the use of sacrificial layers in microfabrication technology, here we propose a novel method for shape setting nitinol wires using a sacrificial metal fixture. In this process, the nitinol wires are first aligned inside copper hypotubes. Next, the forming process is done using hand-held tools to shape complex geometrical structures, annealing the nitinol reinforced by copper, and then selectively etching copper hypotubes in ammonium persulfate solutions. In this process, other sacrificial cores, which are 3D printed or cast from low-cost polymers, are also used. This combination of polymeric cores and minimal use of metals enables reducing the cost and the turnaround time. As a proof of concept, we showed that this process was capable of fabricating springs with mm or sub-mm diameters. The result showed a change of less than 5% in the intended diameter of the nitinol spring with diameters ranging from ~ 0.7 to 1.9 mm, which confirms copper as a suitable sacrificial fixture to obtain the desired complex geometry for nitinol. A metric, based on the elastic strain stored in copper is suggested to predict the possible variation of the intended dimensions in this process. Finally, to demonstrate the potential of this method, as proof of concept, we fabricated NiTi wire frames designed for anchoring through the atrial septum. These frames demonstrated septal defect occluders that were designed based on a patient's cardiac image available in the public domain. This low-cost rapid fabrication technique is highly beneficial for a variety of applications in engineering and medicine with specific applications in rapid prototyping of medical implants.

Assessment of degradability and endothelialization of modified poly L-lactic acid (PLLA) atrial septal defect (ASD) occluders over time in vivo.

OBJECTIVE: To evaluate the fiber-degradation and endothelialization of a modified poly L-lactic acid (PLLA) atrial septal defect (ASD) occluder for a long time in vivo. METHODS: A total of 57 New Zealand rabbits were selected to establish the vasculature implantation model, which would be used to characterize the mechanical properties and pathological reaction of PLLA filaments (a raw polymer of ASD occluder). In total, 27 Experimental piglets were used to create the ASD model for the catheter implantation of PLLA ASD occluders. Then, X-ray imaging, transthoracic echocardiography, histopathology, and scanning electron microscope (SEM) were performed in the experimental animals at 3, 6, 12, and 24 months after implantation. RESULTS: In the rabbit models, the fibrocystic grade was 0 and the inflammatory response was grade 2 at 6 months after vasculature implantation of the PLLA filaments. The mass loss of PLLA filaments increased appreciably with the increasing duration of implantation, but their mechanical strength was decreased without broken. In the porcine models, the cardiac gross anatomy showed that all PLLA ASD occluders were stable in the interatrial septum without any vegetation or thrombus formation. At 24 months, the occluders had been embedded into endogenous host tissue nearly. Pathological observations suggested that the occluders degraded gradually without complications at different periods. SEM showed that the occluders were endothelialized completely and essentially became an integral part of the body over time. CONCLUSION: In the animal model, the modified PLLA ASD occluders exhibited good degradability and endothelialization in this long-term follow-up study.

Atrial septal hematogenous cyst with calcification mimicking myxoma: A rare case.

A 61-year-old female presented with right atrial mass during physical examination. Contrast-enhanced left heart echocardiography revealed a mass with the size of 32*23 mm in the right atrium, attached to the atrial septum; there was a certain degree of activity and deformation. MRI showed a mass of about 35*22 mm in the right atrium adjacent to the atrial septum, which was diagnosed with right atrial myxoma. Intraoperative TEE showed that the mass was located in the atrial septum close to the inferior vena cava and spontaneous echo contrast with hyperechoic images within the mass. The lesion was resected under cardiopulmonary bypass. Pathological examination revealed that the filling defect was an atrial septal hematogenous cyst with calcification.

Long-Term Outcomes of Unrepaired Isolated Partial Anomalous Pulmonary Venous Connection With an Intact Atrial Septum.

The natural history of an unrepaired isolated partial anomalous pulmonary venous connection(s) (PAPVC) and the absence of other congenital anomalies remains unclear. This study aimed to expand the understanding of the clinical outcomes in this population. Isolated PAPVC with an intact atrial septum is a relatively uncommon condition. There is the perception that patients with isolated PAPVC are usually asymptomatic, that the lesion generally has a limited hemodynamic impact, and that surgical repair is rarely justified. For this retrospective study, we reviewed our institutional database to identify patients with either 1 or 2 anomalous pulmonary veins that drain a portion of but not the complete ipsilateral lung. Patients with previous surgical cardiac repair, coexistence of other congenital cardiac anomalies that would result in either pretricuspid or post-tricuspid loading of the right ventricle (RV), or scimitar syndrome were excluded. We reviewed their clinical course over the follow-up period. We identified 53 patients; 41 with a single and 12 with 2 anomalous PAPVC. A total of 30 patients (57%) were men, with a mean age at the latest clinic visit of 47 ± 19 years (18 to 84 years). Turner syndrome (6 of 53, 11.3%), bicuspid aortic valve (6 of 53, 11.3%), and coarctation of the aorta (5 of 53, 9.4%) were commonly associated anomalies. A single anomalous left upper lobe vein was the most commonly identified variation. More than half of the patients were asymptomatic. Cardiopulmonary exercise test demonstrated a maximal oxygen consumption of 73 ± 20% expected (36 to 120). Transthoracic echocardiography demonstrated a mean RV basal diameter of 4.4 ± 0.8 cm, RV systolic pressure of 38 ± 13 (16 to 84) mm Hg. A total of 8 patients (14.8%) had ≥moderate tricuspid regurgitation. Cardiac magnetic resonance in 42 patients demonstrated a mean RV end-diastolic volume index of 122 ±3 0 ml/m2 (66 to 188 ml/m2), of which in 8 (14.8%), it was >150 ml/m2. Magnetic resonance imaging-based Qp:Qs was 1.6 ± 0.3. A total of 5 patients (9.3%) had established pulmonary hypertension (mean pulmonary artery pressure ≥25 mm Hg). In conclusion, isolated single or dual anomalous pulmonary venous connection is not necessarily a benign congenital anomaly because a proportion of patients develop pulmonary hypertension and/or RV dilation. Regular follow-up and on-going patient surveillance with cardiac imaging is advised.

Novel operative technique for Scimitar syndrome: Posterior flap technique.

Various surgical techniques have been reported for Scimitar syndrome, because of the heterogenous anatomy of the disease. We developed a novel surgical method to repair Scimitar syndrome, in which, a new pulmonary venous route is constructed behind the inferior vena cava using autologous flaps of the inferior vena cava and the interatrial septum. An adult case of Scimitar syndrome was repaired by this method with good results.