Outcome of transcatheter atrial septal defect closure in a nationwide cohort.

BACKGROUND: Transcatheter (TC) atrial septal defect (ASD) closure has been the mainstay of therapy for secundum-type ASDs for over 20 years. AIMS: This nationwide cohort evaluated the long-term outcome of transcatheter-closed ASDs. METHODS: The study enrolled every transcatheter ASD closure performed in Finland from 1999 to 2019. Five age, sex, and municipality-matched controls per ASD patient were gathered from the general population. The median follow-up period was 5.9 years (range 0-20.8). We used the hospital discharge register to gather all hospital visits and diagnoses. Closure complications and echocardiographic changes were collected from the electronic health records. RESULTS: Transcatheter ASD closure was performed in 1000 patients (68.5% females) during the study period. The median (range) age at the time of the procedure was 37.9 (1.8-87.5) years. ASD patients had an increased risk for new-onset atrial fibrillation (RR 2.45, 95% CI: 1.84-3.25), migraine (RR 3.61, 95% CI: 2.54-5.14), ischemic heart disease (RR 1.73, 95% CI: 1.23-2.45), ventricular fibrillation/tachycardia (RR 3.54 (95% CI: 1.48-8.43) and AV conduction disorder (RR 3.60, 95% CI: 1.94-6.70) compared to the control cohort. Stroke risk was not increased (RR 1.36, 95% CI: 0.91-2.03). Adverse events occurred in 6.3% (n = 63) of the patients, including four erosions and ten device embolizations. CONCLUSION: After TC closure of ASD, patients had a higher risk of new-onset atrial fibrillation and migraine than controls without ASD. As novel findings, we found an increased risk for ischemic heart disease, AV conduction disorders, and ventricular fibrillation/tachycardia.Key messagesEven though patients have an excellent overall prognosis after percutaneous ASD closure, the increased incidence of major comorbidities like atrial fibrillation and heart failure prompts more thorough lifelong follow-up.This study's novel findings revealed the increased risk for ischemic heart disease, AV conduction disorders, or ventricular tachycardia/fibrillation during the follow-up.Major complications after the closure are rare; erosion is seen in 0.4% of the patients and embolization in 1.0% of the patients.

Headache after transcatheter closure of atrial septal defect: An attempt to explain its origin in the pediatric population.

BACKGROUND: Transcatheter closure of atrial septal defect (ASD) has become the treatment of choice for most patients. About 5% of them suffer from transient headache episodes (THE) after the procedure, whose etiology is unclear. AIMS: To evaluate risk factors for THE occurrence after transcatheter closure of ASD in the pediatric population. METHODS: Eight hundred and forty patients, after transcatheter ASD closure with nitinol devices, from a single center, were included in retrospective analysis. THE was defined as occurring up to 24 hours after the procedure. A logistic regression model including age, weight, ASD diameter, device size, presence of nitinol coating on the device, fluoroscopy time, application of balloon calibration, device oversizing, and residual shunt after 24 hours was created to evaluate risk factors for THE occurrence. RESULTS: There were 40 patients with THE (4.8%), 70% female and 30% male. The median age was 13 (7.35-16) years. In patients with headache, balloon calibration (BC) was performed more frequently (82.5% vs. 43.3%; P <0.001). The balloon waist median (interquartile range [IQR]), 19 (16-22) mm vs. 15 mm (12-18) mm (P <0.001), and device size median (IQR), 18 (13.5-22) mm vs. 14 (11-17) mm (P <0.001) were larger, and residual shunt after 24 hours (12.5% vs. 4.9%; P = 0.03) and a year (7.5 vs. 1.0%; P <0.001) were more frequent. ASD size and the prevalence of double/multiple ASD were similar in both groups. Age, BC application, no nickel release protection, duration of fluoroscopy, and device oversizing were predictors of THE (P <0.001). CONCLUSIONS: BC during percutaneous ASD closure and the lack of a protective layer against nickel release on the device are risk factors for headache occurrence in the early postprocedural period.

Iatrogenic Atrial Septal Defect Closure Through the Steerable Guide Catheter: Description of Technique and Single-Center Experience.

OBJECTIVES: To introduce a novel method of direct iatrogenic atrial septal defect (iASD) closure through the MitraClip steerable guide catheter (SGC). BACKGROUND: MitraClip implantation requires transseptal puncture and the creation of an iASD. There are relatively rare instances, such as hemodynamically significant shunting or concerns for embolus, where iASD must be closed during index procedure. In these instances, it may be beneficial to not give up access to left atrium. METHODS: We retrospectively reviewed all iASD closures during MitraClip implantation at our institution from 2015 to 2020. Cases where an ASD occluder was deployed directly through SGC were included. RESULTS: Eleven patients had immediate iASD closure through the SGC. Indications for using this method included concern for paradoxical embolus, large defect size and/or significant shunting. Closure device sizes ranged from 8 to 22 mm. Mean time from removal of clip delivery system to occlusion of iASD was 14.6 minutes. There were no procedural complications related to iASD closure using this method. CONCLUSION: Closure of iASD intra-procedurally directly through transseptal guide sheath via the method described was safe and allowed for continuous left atrium access.

Safety and Efficacy of the Amplatzer Septal Occluder: A Systematic Review and Meta-Analysis.

OBJECTIVES: To assess the safety and efficacy of the Amplatzer Septal Occluder in the closure of secundum type atrial septal defects. BACKGROUND: The Amplatzer Septal Occluder (ASO; Abbott, St. Paul, MN) is an FDA-approved device for percutaneous closure of secundum type atrial septal defects (ASD). Previous small cohort trials have shown a favorable safety and technical efficacy profile. METHODS: We conducted a systemic review and meta-analysis of all prospective case series and controlled trials that evaluated the ASO's safety and implant efficacy. The primary endpoint was the technical success rate of implantations. Secondary outcomes included proportions of arrhythmias and embolism specific-adverse events. RESULTS: We included a total of 12 studies with 2972 patients. The ratio of device implantation was 2:1 by sex [female: male]. Pooled technical success rate of implantation was 98% (95% CI: 0.968-0.990, P < 0.01). The cumulative adverse event rate was 5.1% (95% CI: 0.035-0.068, P < 0.01), which included arrhythmia and embolism specific adverse event rates of 1.8% (95% CI: 0.007-0.032, P < 0.01) and 0.7% (95% CI: 0.002-0.013, P < 0.01), respectively. Sensitivity analysis did not significantly affect pooled outcomes for success rate and adverse events; both forest plot and Begg's and Egger's regression tests supported symmetricity. CONCLUSION: A high likelihood of technical success can be expected when implanting the ASO in secundum type ASDs. Adverse event rates are expected for one in twenty patients, and thus, our results support the safe use of ASO in secundum type ASDs closure. CONDENSED ABSTRACT: The AMPLATZER Septal Occluder is an FDA-approved device for percutaneous closure of secundum type atrial septal defects (ASD). We conducted a systemic review and meta-analysis of all prospective case series and controlled trials that evaluated the ASO's safety and implant efficacy. We included a total of 12 studies with 2972 patients. Pooled technical success rate of implantation was 98% (P < 0.01). The cumulative adverse event rate was 5.1% (P < 0.01), 1.8% (P < 0.01) rate of arrhythmias, and 0.7% (P < 0.01) rate of embolisms. A high likelihood of technical success can be expected with a low rate of adverse events.

Prevalence of iatrogenic atrial septal defects (iASD) after mitral valve (MV) transcatheter edge-to-edge repair (TEER) in the long-term follow-up.

OBJECTIVES: To investigate prevalence of iatrogenic atrial septal defects (iASDs) after mitral valve (MV) transcatheter edge-to-edge repair (TEER) with the MitraClip in the long-term follow-up. BACKGROUND: MV TEER requires transseptal puncture using a large 22 F sheath. Prevalence, impact and haemodynamic effects of these iASDs remain unknown in the long-term follow-up. METHODS: This prospective study enrolled patients who had undergone first-time TEER at our university hospital between January 2017 and June 2018 for a clinical long-term follow-up study. Prevalence of iASD was investigated 12 months post-TEER using transoesophageal echocardiography (TEE). Study protocol further consisted of transthoracic echocardiography (TTE) and exercise testing. Incidence of all-cause death was compared 12 months post-TEE follow-up. This study was approved by local ethics committee. RESULTS: 48 patients participated in clinical follow-up examinations. Median time between TEER and clinical follow-up examination (TEE, TTE, exercise testing) was 19.5 (IQR: 7.0) months after TEER. Persistent iASD was found in 41.7% of patients. TEER was found to be equally effective in reducing MR and clinical symptoms in both groups at baseline as well as follow-up. Procedural fluoroscopy and device times were significantly longer in the iASD group. MR reduction and functional status (New York Heart Association Class, 6 Minute Walking Test distance) were similar in both groups. Nevertheless, a significant decrease in systolic pulmonary artery pressure (sPAP) and significantly smaller atrial diameters were observed in patients with iASD at follow-up. CONCLUSION: Prevalence of iASDs after TEER in long-term follow-up was about 41%. Although a significant reduction of sPAP and better left atrial reverse remodelling were accomplished in patients with iASD, clinical impact appears low. Manipulation at the atrial septum might play a key role in creating persisting iASD.

Incidence and clinical relevance of persistent iatrogenic atrial septal defect after percutaneous mitral valve repair.

Percutaneous mitral valve repair (PMVR) requires transseptal puncture and results in iatrogenic atrial septal defect (iASD). The impact of persistent iASD was previously investigated. However, data were diverse and inconclusive. 53 patients who underwent MITRACLIP were retrospectively included. Based on the presence of iASD in transesophageal echocardiography (TEE) after 6 months, patients were divided in two groups (iASD group vs. non-iASD group). Impact of iASD on outcome at 6 months and at two years was evaluated. Persistent iASD was detected in 62% of patients. Independent predictors for persistent iASD were female gender and reduced left ventricular ejection fraction. At 6-month follow-up, there was no difference in reduction of NYHA class (ΔNYHA = 1.3 ± 1 in iASD group vs. 0.9 ± 1 in non-iASD group, p = 0.171). There was a significant difference in right ventricular end diastolic diameter (RVEDd) (42 ± 8 mm in iASD-group vs. 39 ± 4 mm in non-iASD group, p = 0.047). However, right ventricular systolic function (TAPSE) (14 ± 7 mm in iASD group vs. 16 ± 8 mm in non-iASD group, p = 0.176) and right ventricular systolic pressure (RVSP) (40 ± 12 mmHg in iASD group vs. 35 ± 10 mmHg in non-iASD group, p = 0.136) were still comparable between both groups. At 2 years follow-up, there was no significant difference regarding rate of rehospitalization (24% vs 15%, p = 0.425) or mortality (12% vs 10%, p = 0.941) between both groups. Incidence of persistent iASD after MITRACLIP is markedly high. Despite the increase in right ventricular diameter in patients with persistent iASD, these patients were not clinically compromised compared to patients without persistent iASD.

Iatrogenic Atrial Septal Defect After Percutaneous Mitral Valve Repair With MitraClip: Should We Consider Closing Them Routinely?

Percutaneous MitraClip intervention for treatment of severe mitral regurgitation in high surgical risk patients requires large-diameter transseptal sheaths that can result in iatrogenic atrial septal defect (iASD), and its prevalence is higher compared with non-MitraClip procedures. This iASD is not routinely closed because the possible consequences are still not fully understood. However, we believe it is important to identify patients who may benefit from its closure immediately after the procedure to prevent hemodynamic deterioration and long-term negative clinical outcomes. We describe our experience with 2 patients who required iASD closure after MitraClip procedure due to right-to-left shunt resulting from increase in right heart pressures.

Right-to-Left Shunt Through Iatrogenic Atrial Septal Defect After MitraClip Procedure.

OBJECTIVES: The aim of this study was to investigate the incidence, characteristics, hemodynamic conditions, and clinical significance of right-to-left (R-L) shunt through an iatrogenic atrial septal defect (iASD) after the MitraClip procedure. BACKGROUND: R-L shunt through an iASD after the MitraClip procedure has not been well investigated. METHODS: From 2014 to 2017, 385 consecutive patients with mitral regurgitation underwent the MitraClip procedure. iASD was assessed using intraprocedural transesophageal echocardiography. Right and left heart catheterization was used to assess the hemodynamic status of patients. All patients provided written informed consent for the procedure. All data for this study were collected from an established interventional cardiology laboratory database approved by the Cedars-Sinai Medical Center Institutional Review Board. RESULTS: R-L shunt was observed in 20 patients (5%). In 7 of these patients (35%), R-L shunt was accompanied by acute deoxygenation. Prevalence of severe tricuspid regurgitation (55% vs. 20%; p = 0.001), serum B-type natriuretic peptide (664 pg/ml [434 to 1,169 pg/ml] vs. 400 pg/ml [195 to 699 pg/ml]; p = 0.006), mean pulmonary artery pressure (38 mm Hg [34 to 45 mm Hg] vs. 29 mm Hg [22 to 37 mm Hg]; p < 0.001), and right atrial pressure (19 mm Hg [13 to 20 mm Hg] vs. 10 mm Hg [7 to 14 mm Hg]; p < 0.001) were significantly higher in patients with R-L shunt than in those with left-to-right shunt. Patients with R-L shunt also showed a more prominent reduction in the left atrial V-wave and mean pressure from baseline to post-procedure compared with those with left-to-right shunt (-22.8 ± 2.6 mm Hg vs. -11.8 ± 0.9 mm Hg [p = 0.002] and -7.9 ± 0.8 mm Hg vs. -4.0 ± 0.4 mm Hg [p = 0.003], respectively). CONCLUSIONS: R-L shunt through an iASD was observed in 5% of patients who underwent the MitraClip procedure and in one-third of patients with R-L shunt presented acute deoxygenation. Elevated right atrial pressure concomitant with pulmonary hypertension and significant reduction in left atrial pressure after MitraClip deployment were associated with R-L shunt.

Percutaneous Atrial Septal Defect Closure in Adult Ebstein's Anomaly with Exertional Hypoxemia.

In Ebstein's anomaly, percutaneous atrial septal defect (ASD) closure for the treatment of hypoxemia due to a right-to-left interatrial shunt remains controversial. We report the case of a 40-year-old woman with Ebstein's anomaly who developed cyanosis and shortness of breath on exercise. Her symptoms improved after percutaneous ASD closure and her clinical course has been good during follow-up. The balloon ASD occlusion test, combined with dobutamine stimulation before the procedure, is useful to confirm treatment indication. A prior electrophysiological evaluation is also important because Ebstein's anomaly is often complicated by atrioventricular recurrent tachycardia.

Low incidence of atrial septal defects in nonmammalian vertebrates.

The atrial septum enables efficient oxygen transport by separating the systemic and pulmonary venous blood returning to the heart. Only in placental mammals will the atrial septum form by the coming-together of the septum primum and the septum secundum. In up to one of four placental mammals, this complex morphogenesis is incomplete and yields patent foramen ovale. The incidence of incomplete atrial septum is unknown for groups with the septum primum only, such as birds and reptiles. We found a low incidence of incomplete atrial septum in 11 species of bird (0% of specimens) and 13 species of reptiles (3% of specimens). In reptiles, there was a trabecular interface between the atrial septum and the atrial epicardium which was without a clear boundary between left and right atrial cavities. In developing reptiles (four squamates and one crocodylian), the septum primum initiated as a sheet that acquired perforations and the trabecular interface developed late. We conclude that atrial septation from the septum primum only results in a low incidence of incompleteness. In reptiles, the atrial septum and atrial wall develop a trabecular interface, but previous studies on atrial hemodynamics suggest this interface has a very limited capacity for shunting.

Prospective evaluation of iatrogenic atrial septal defect after cryoballoon or radiofrequency catheter ablation of atrial fibrillation-"EVITA" study.

PURPOSE: Iatrogenic atrial septal defect (IASD) after catheter ablation (CA) for atrial fibrillation (AF) due to transseptal puncture (TSP) can occur. The aim of this prospective study was to describe the incidence of IASD and to detect any cerebrovascular accident (CVA) after radiofrequency (RF) and cryoballoon (CB) CA. METHODS: Between July 2014 and September 2016, 94 patients (pts) (RF; 48, CB; 46, 30 (31.9%) women, mean age = 60 ± 9.7 years) with paroxysmal AF were enrolled who underwent CA procedure for the first time. During RF ablation a single (n = 30, 62.5%) or double (n = 18, 37.5%) TSP was performed. Transoesophageal echocardiography before the procedure and at the 3-month and 12-month follow-up (FU) was accomplished. During the FU period, we evaluated the occurrence of any postprocedural CVA. RESULTS: At the 3-month FU, IASD was detected in 17/94 (18.1%) pts; in 9/48 (18.8%) pts in the RF while in 8/46 (17.4%) pts in the CB group (p = 0.866), all of them with left-to-right shunt. In the RF group, 6/30 (20%) pts with a single TSP while 3/18 (16.7%) pts in the double TSP group had IASD (p = 0.780). 14/17 (82.4%) IASDs showed high spontaneous closure rate at the 12-month FU. None of the pts died or suffered from CVA. CONCLUSION: Persistent IASD can occur rather frequently following AF CA. No significant difference was observed between the RF and CB techniques concerning the presence of IASD at 3-month. IASDs showed a high spontaneous closure rate. No cerebral thromboembolic event was observed in the 12-month FU period.

Iatrogenic Arteriovenous Fistula and Atrial Septal Defect Following Cryoballoon Ablation for Atrial Fibrillation - Two Correctable Causes of Right Heart Failure.

BACKGROUND Catheter ablation for atrial fibrillation is an important therapeutic intervention. One of the most frequent complications of this procedure is vascular issues including arteriovenous fistula. Iatrogenic atrial septal defect (IASD) has been reported as a complication of transseptal puncture; however, no data are available demonstrating any coexistent of arteriovenous fistula with IASD. CASE REPORT A 61-year-old female patient was admitted to our center for catheter ablation for persistent atrial fibrillation. Her past medical history was significant for cryoballoon ablation for atrial fibrillation in 2015, which was subsequently complicated by hematoma and arteriovenous fistula at puncture site. After general surgery consultation, the patient was qualified for conservative treatment. To exclude left atrial thrombus before redo procedure, transesophageal echocardiography was performed which visualized the presence of 9-mm atrial septal defect with left-to-right shunting, detecting right-to-left shunting using Valsalva maneuver. No significant valvular abnormalities were identified. The next day, pulmonary vein isolation for atrial fibrillation was performed. One month later, a control transthoracic echocardiogram (TTE) revealed hemodynamic significant left-to-right shunting with Qp/Qs 2.0 and high probability of pulmonary hypertension. Vascular surgery for arteriovenous fistula was successfully performed in October 2018. Subsequent TTE, performed a month later, confirmed no left-to-right shunting and no signs of pulmonary hypertension or diminishment of the right atrium. CONCLUSIONS Vascular access during catheter ablation for atrial fibrillation may result in arteriovenous fistula. This condition might affect right atrium pressure leading to increased diameter of previous puncture site at the interatrial septum, causing IASD with significant shunting. In this group of patients, arteriovenous fistula should be treated as soon as possible.

A Very Long-term Longitudinal Study on the Evolution and Clinical Outcomes of Persistent Iatrogenic Atrial Septal Defect After Cryoballoon Ablation.

BACKGROUND: Persistent iatrogenic atrial septal defect (iASD) is a common but poorly characterized complication after cryoballoon (CB) pulmonary vein isolation (PVI) procedures. We therefore investigate its prevalence, evolution, risk factors, and clinical outcomes in a prospective longitudinal study. METHODS: A total of 108 patients (41 women, mean age 57 ± 11.3) underwent CB PVI for AF. Serial transesophageal echocardiography (TEE) was performed 9 months and then annually until 6 years after the procedure to study the characteristics of persistent iASD. RESULTS: Persistent iASD occurred in 33 (30.6%) patients 9 months after CB PVI. Spontaneous closure of iASD was found in 6 (22.2%) and 3 (15.8%) patients 2 and 3 years after the procedures, respectively. No spontaneous closure was observed on 4, 5, and 6-year TEE follow-up. The projected long-term persistence rate of iASD after CB PVI was therefore 20% (30.6% × 0.778 × 0.842). Using multivariate logistic regression, a higher number of cryoapplications (≥ 2 minutes) was the only independent predictor of persistent iASD 9 months after CB PVI (odds ratio [OR] 1.207; 95% confidence interval [CI], 1.033-1.411, P = 0.018). Two (1.9%) patients with significantly larger iASD size than the others (long diameter 12.6 ± 0.8 vs 3.7 ± 1.5 mm, P < 0.001; short diameter 10.9 ± 0.2 vs 3 ± 1.1 mm, P < 0.001) required percutaneous closure because of exertional dyspnea and right ventricular enlargement. Over 129.7 patient-years follow-up, during which iASD persisted, there was no occurrence of neurologic events. CONCLUSIONS: Approximately one fifth of patients undergoing CB PVI will have permanently persistent iASD. Patients with defect sizes of greater than 10 mm may need percutaneous closure due to significant left-to-right shunting.

Interatrial Septal Dissection Complicating a MitraClip Procedure.

Left atrial dissection is an exceedingly rare complication of cardiac surgery, with an incidence of 0.16%-0.84%. We report the first case of interatrial dissection and hematoma in association with the MitraClip procedure. Hemodynamically stable patients can be managed conservatively, with echocardiographic imaging, often with resolution of the dissection over the course of weeks. Our patient remained hemodynamically stable and asymptomatic post operation; at 1-month follow-up, echocardiogram showed resolution of the interatrial septal dissection.

Iatrogenic atrial septal defect post mitral valve in valve implantation.

A 75 year-old female with symptomatic severe mitral regurgitation of a bio-prosthetic valve secondary to valve leaflet perforation due to endocarditis underwent a mitral valve in valve replacement in an existing Hancock 27 mm valve using a trans-femoral/trans-septal approach. The procedure was complicated by an iatrogenic atrial septal defect post trans-septal puncture causing a severe right-to-left shunt due, possibly, to the combination of severe pulmonary hypertension and moderate tricuspid regurgitation the patient had suffered from at base line. Once the sheath was removed an immediate desaturation was observed which required emergent closure with an AMPLATZER ASD Occluder device (St. Jude Medical/Abbott Structural, St. Paul, Minnesota, MN). This stabilized the patient and returned her blood oxygen levels to normal. The case brings forth a rare but important complication that may occur during trans-septal procedures especially when using large sheaths. It emphasizes the importance of proper echocardiographic and hemodynamic evaluation prior to such procedures in order to be prepared for such complications.

High rate of persistent iatrogenic atrial septal defect after single transseptal puncture for cryoballoon pulmonary vein isolation.

PURPOSE: Congenital atrial septal defect (ASD) is associated with increased morbidity, whereas little is known about the rate of spontaneous closure, associated clinical and echocardiographic parameters, or complications of iatrogenic atrial septal defect (iASD) beyond 1 year of follow-up. Persistent iASD after transseptal puncture for PVI has been described in up to 38% of small cohorts of patients in short-term follow-up after transseptal puncture. We sought to investigate the course of iASD after single transseptal puncture for first pulmonary vein isolation (PVI) with cryoballoon, along with possible risk factors for persistent iASD. METHODS: After a first PVI with cryoballoon, 102 patients (64 ± 10 years, 64% male) underwent long-term clinical follow-up and comprehensive transthoracic and transesophageal echocardiographic study. RESULTS: Prevalence of iASD after PVI was 37% after 2.9 (1.6-4.9) years. No clinical complications or deterioration of echocardiographic parameters were associated with iASD. Lower left atrial appendage flow velocity was associated with higher risk of persistence of iASD (3.5% for every 1 cm/s decrease, p = 0.002). CONCLUSIONS: Despite a high rate of iASD after cryoballoon PVI in long-term follow-up, this was not associated with increased clinical complications. Lower LAA velocity was associated with higher risk of persistent iASD. Repeated routine echocardiographic follow-up may not be necessary in these patients.

Persistence of an iatrogenic atrial septal defect after a second-generation cryoballoon ablation of atrial fibrillation.

Persistent iatrogenic atrial septal defects (iASDs) can be observed after intervention requiring a left atria (LA) access, including pulmonary vein isolation (PVI) of atrial fibrillation (AF). We investigated the incidence of iASDs post-second-generation cryoballoon ablation and the pre-procedural predictors. Eighty-three paroxysmal AF patients underwent PVI using second-generation cryoballoons. The LA was accessed with single 15-Fr steerable sheaths following a radiofrequency transseptal puncture, and the iASD was evaluated with transthoracic echocardiography (TTE), a median of 9.3 (7.1-13.3) months post-procedure. All patients underwent pre-procedural contrast-enhanced multi-detector computed tomography (CT) to evaluate the LA and PV anatomy. iASDs were detected by TTE in 7 (8.4%) patients, a median of 15.5 (6.8-17.3) months post-procedure. Patients with iASDs had significantly larger LA volumes and smaller atrial septal angles, defined as the angle between the atrial septum and sagittal line on the horizontal section at the height of the fossa ovalis, which could be the transseptal puncture site measured on CT, and more likely hypertension than those without. Multivariate analyses revealed that the atrial septal angle was the sole predictor of iASDs [odds ratio 0.764, 95% confidence interval (CI) 0.624-0.935, p = 0.009], and the optimal cut-off value was 57.5° (sensitivity 85.7%, specificity 88.2%, 95% CI 0.873-0.995, p < 0.0001). Patients with iASDs were asymptomatic and had no adverse clinical events during a 17.7 (14.4-25.8) month median follow-up. iASDs were still detectable in 8.4% of patients a median of 15.5 months after the second-generation CB ablation, and the atrial septal angle might aid in predicting persistent iASDs.