Persistent iASD Research Articles

Impact of Persistent Iatrogenic Atrial Septal Defect following MitraClip.

Prior studies have reported conflicting results of persistent iatrogenic atrial septal defect (iASD) and its impact following a transcatheter edge-to-edge repair (TEER) procedure. This study aims to evaluate the incidence of iASD and its clinical and hemodynamic impact after a TEER. Consecutive patients who underwent a TEER procedure from June 2014 to September 2020 at the Mayo Clinic were identified. The presence of iASD was retrospectively identified on post-procedure transthoracic echocardiography (TTE) to group patients into an iASD+ group and an iASD- group for comparison of prognosis and cardiac function. A total of 316 patients were included; the mean age was 79.1 ± 9.1 years, and 67.7% were male. Persistent iASD was diagnosed in 108 (34.2%) patients. There was no difference concerning all-cause mortality, heart failure hospitalization, and stroke/TIA between groups at follow-up (median follow-up of 9 months). Post-procedure TTE demonstrated no differences regarding right ventricle (RV) and left ventricle (LV) dimensions and function, including TAPSE (15.2 ± 4.6 vs. 15.4 ± 5.5 mm, p = 0.875), and LV ejection fraction (51.1 ± 14.0% vs. 51.3 ± 13.9%, p = 0.933). However, patients with iASD had higher RV systolic pressure (48.7 ± 14.4 vs. 45.5 ± 14.5 mmHg, p = 0.042) compared with patients without iASD. Notwithstanding higher RV pressures, patients with persistent iASD had no hemodynamic compromise and an equal prognosis compared with those without a residual atrial defect after a TEER procedure. These findings support the mid-term safety of procedures in which an interatrial defect needs to be created and would argue against the need for interventional closure.

931 EVALUATION OF IATROGENIC ATRIAL SEPTAL DEFECT CLOSURE AFTER TEER

Abstract Iatrogenic atrial septal defect (iASD) represents one of the main access-related cardiac complications after trancatheter edge to edge (TEER) mitral valve repair with Mitraclip system. Transesophageal echocardiography (TEE) guiding supports a controlled and safe transseptal puncture. The rate of persistent iASD is 57, 50, and 25% after 1, 6, and 12 months post procedure. An elevated left atrial pressure after clip positioning correlates with iASD persistence. Its clinical impact is controversially discussed: Post-TEER iASD has been associated with right heart volume overload, as well as increased rates of heart failure (HF) hospitalization and death in some studies. In contrast, other studies have shown an association between post-TEER iASD and improved hemodynamics. In theory, creation of an iASD can decompress an overloaded left atrium, mitigating heart failure. Some studies have demonstrated that iASD closure can reduce significantly both right and left heart failure symptoms. We did a retrospective study enrolling in the period 2012-2022 twenty-one patients with severe mitral regurgitation treated with TEER. Our aim was to evaluate the clinical outcomes (symptoms, signs of heart failure, NYHA functional class) and echocardiographic parameters (PAPs, TAPSE, Right Atrium Area) in two group of patients: Group A underwent iASD closure during the TEER and Group B after one month following the TEER. At 1-month follow-up all patients with repaired mitral regurgitation showed an improvement in the NYHA class (from IV-III to II-I) and no need for re-hospitalization with no significant differences between two groups. In the Group A there were two adverse events during the recovery (2 major bleeding); while there were no adverse events in patients undergoing iASD closure after wise. There was 1 death in the first month after the procedure in group A, while there wasn't any in group B. Statistical analysis showed no significant differences in terms of NYHA class improvement in the two groups (p=0.91). We observed a greater reduction in PAPs in patients going to encounter intraprocedural DIA closure which was found to be statistically significant (p=0.01). Regarding TAPSE, there was a difference in terms of improvement which was found to be greater in the group A. However, this finding was not found to be statistically significant. We also assessed the right atrium area: in group A, we registered a mean preprocedural value of 28 cmq and a postprocedural value of 34 cmq; in group B the values were 20 cmq and 24 cmq, respectively, with a nonstatistically significant difference in terms of atrial enlargement post device placement. In conclusion, we can assume that the improvements in symptomatology are not closely related to iASD closure. However, it must considered that patients in group A had more unfavorable echocardiographic values before the procedure than those in group B, and probably, if we had not closed the iASD immediately during the procedure, these patients would have had worse symptomatology. Therefore, targeted patient selection is essential.

Fate of iatrogenic atrial septal defects following mitral transcatheter edge-to-edge repair – a subanalysis of the MITHRAS trial

Persisting iatrogenic atrial septal defects (iASD) after transcatheter mitral edge-to-edge repair (M-TEER) are associated with impaired outcomes. We investigated the natural history of relevant iASDs with left-to-right shunting post-M-TEER, predictors of spontaneous closure of iASD between 1 and 6 months post-M-TEER, and outcomes (heart failure [HF] hospitalization) in patients with spontaneous closure versus those with persistent iASD 6 months post-M-TEER. Patients with a relevant iASD 1-month post-M-TEER, who were treated conservatively in the randomized controlled MITHRAS trial, underwent clinical follow-up including transesophageal echocardiography 6 months post-M-TEER. Overall, 36 patients (median 77 [interquartile range 65–81] years; 36% women) completed the 6-months follow-up. Six (17%) patients had a spontaneous closure of the iASD. The eccentricity index of the iASD 1-month after M-TEER was the strongest predictor for spontaneous closure (Odds ratio 3.78; 95% confidence interval 1.26–11.33, p = 0.01) and an eccentricity index of < 1.9 provided a sensitivity of 77% at a specificity of 83% for iASD persistence (Area under the curve 0.83, p < 0.001) within 6-months post M-TEER.At follow-up, a numerical difference in the endpoint of HF hospitalization between the spontaneous closure and the residual shunt group (0% vs. 20%, p = 0.25) was observed. The eccentricity of the iASD was the strongest predictor for spontaneous closure at 1-months and an eccentricity index of < 1.9 is associated with a high persistence rate for 6 month after M-TEER. Clinical Trial Registration ClinicalTrials.gov https://clinicaltrials.gov/ct2/show/NCT03024268 Identifier: NCT03024268.Graphical a (red) is reflecting the mayor lengthwise dimension and b (blue) the mayor oblique dimension. The eccentricity index is calculated by dividing a through b. (Open circle) is depicting an example for a round iASD and (Open rhombus) an example for an eccentric iASD 1 month after M-TEER.

Iatrogenic atrial septal defects after transseptal puncture for percutaneous left atrial appendage occlusion and their hemodynamic effects.

Percutaneous left atrial appendage occlusion (LAAO) requires puncture of the interatrial septum. The immediate hemodynamic effects of iatrogenic atrial septal defects (iASD) after LAAO have not been examined so far. We aimed at evaluating these effects through invasive measurements of pressure and oxygen saturation. Moreover, we assessed the incidence of persistent iASD at three months. Forty-eight patients scheduled for percutaneous LAAO were prospectively included in the study. Pressure and oxygen saturation were measured (1) in the right atrium (RA) before transseptal puncture, (2) in the left atrium (LA) through the transseptal sheath after transseptal puncture, (3) in the LA after removal of introducer sheath, and (4) in the RA after removal of introducer sheath. Transesophageal echocardiography was performed at three months to detect iASD. Pressure in the RA increased significantly after removing the introducer sheath (P = 0.034), whereas no difference was found in oxygen saturation in the RA (P = 0.623). Pressure measurement in the LA showed no significant difference after removing the introducer sheath (P = 0.718). Oxygen saturation in the LA also showed no significant difference (P = 0.129). Follow-up transesophageal echocardiogram at 3 months revealed a persistent iASD in 4 patients (8.5 %). Our study suggests that iASD after percutaneous LAAO does not result in significant shunts directly after the procedure, although a significant increase of mean right atrial pressure can be observed. Persistent iASDs after percutaneous LAAO seem to be relatively rare at three months.

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

ObjectivesTo 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.BackgroundMV TEER requires transseptal puncture using a...

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 persistence after percutaneous mitral valve repair: a meta-analysis

Background Percutaneous mitral valve repair (PMVR) requires a puncture of the atrial septum, resulting in iatrogenic atrial septal defect (iASD), which usually causes a transient left-to-right shunt. However, the influencing risk factors for iASD persistence and functional consequences are not fully understood. This meta-analysis aimed to summarise available data on the persistence of iASD following PMVR. Methods The authors conducted a literature search in PubMed/MEDLINE and EMBASE databases to identify studies investigating iASD persistence in PMVR patients. Results Six observational studies (n = 361) met inclusion criteria for the final analysis. Prevalence of persistent iASD was documented with 28% after 12 months follow-up. iASD size increased over time with a diameter of 5.3 ± 0.76 mm after one month and 6.5 ± 0.21 mm after 12 months. Possible predictors of iASD persistence after PMVR appeared to be pre-existing AF (RR 1.24; p = .03), residual mitral regurgitation > II° (RR 2.06; p = .03) and prolonged fluoroscopic time (RR 8.27; p = .01). Patients with iASD persistence had a higher risk for development of right heart overload regarding the increased area of the right atrium (MD 5.24; p = .004) and enlarged diameter of the right ventricle (MD 3.33; p < .0001). Rehospitalization was more frequently reported in iASD patients (RR 9.52; p = .004). Conclusions This meta-analysis proved iASD persistence in 28% of PMVR after 12 months follow-up with a higher risk for right heart volume overload and more frequent rehospitalization compared to patients without iASD persistence. Since percutaneous catheter-based treatments with transseptal approaches are rising, further evidence about the hemodynamic impact of persistent iASD is warranted.

Acute hemodynamic effects of iatrogenic inter-atrial shunts after percutaneous edge-to-edge mitral valve repair

Abstract Background Implantable interatrial shunt devices improve pulmonary vascular function in patients with heart failure by transferring richly oxygenated blood to the right heart. Whether iatrogenic atrial septum defects (iASDs) after percutaneous edge-to-edge mitral valve repair (pMVR) are also associated with beneficial hemodynamic effects has not been investigated. Methods We consecutively enrolled patients with relevant functional (FMR) and degenerative mitral regurgitation (DMR) scheduled for pMVR. Invasive hemodynamic assessments were performed prior to and immediately after the procedure. Results 97 consecutive patients (75.4±9.1 years; 58% female) were prospectively included, 65 (66%) presented with relevant FMR. At baseline when compared to the DMR group, FMR was associated with worse left ventricular (LV) function (LV ejection fraction: 39 vs. 49%; p=0.001), higher NT-proBNP levels (7404 vs. 5214 pg/mL; p=0.023), worse renal function (serum creatinine: 1.7 vs. 1.3 mg/dL; p=0.019), and higher usage of spironolactone (68 vs. 42%; p=0.018) and sacubitril/valsartan (33 vs. 0%; p&amp;lt;0.001). Following pMVR, cardiac output (CO) and systemic blood flow (Qs) increased significantly (CO: 4.6 to 5.5 L/min; p&amp;lt;0.001; Qs: 4.9 to 5.8 L/min; p=0.002), with more pronounced changes in the FMR subgroup (ΔCO: 1.0 vs. 0.6 L/min; Figure 1A; ΔQs: 1.2 vs. 0.1 L/min), when compared to DMR. Pulmonary blood flow (Qp) increased by 26% (4.3 to 5.4 L/min; p=0.008), accompanied by a raise in pulmonary artery (PA) oxygen (O2) saturation from 73 to 77% (p&amp;lt;0.001). Arterial O2 saturation levels remained unchanged (98.3 to 98.7%; p=0.165), confirming no significant changes in systemic oxygenation. These changes were associated with a slight decline in pulmonary vascular resistance (PVR: 250 to 225 dynes*sec/cm5; p=0.369, Figure 1B), and a tendency towards improvement of pulmonary compliance (PAC: 3.6 to 4.0 mL/mmHg; p=0.414). Conclusions Invasively measured CO, Qs, Qp, and mixed-venous PA O2 saturation increased immediately after pMVR, alongside with potentially beneficial effects on pulmonary vasculature with marked improvements in PVR and PAC. These changes were more pronounced in the FMR subgroup. Further studies are required to assess long-term hemodynamic effects and underlying mechanisms of persistent iASDs on pulmonary vascular function. Figure 1. Invasive hemodynamics Funding Acknowledgement Type of funding source: None

P1857Risk calculator for prediction of iatrogenic atrial septal defect persistence following percutaneous mitral valve repair

Abstract Background The rising number of new percutaneous interventions for left-sided heart disease leads to increased occurrence of iatrogenic atrial septal defect (iASD). The percutaneous mitral valve repair (PMVR) for severe, symptomatic mitral regurgitation (MR) also requires intraprocedural puncture of the interatrial septum. In some cases iASD is persisting and becomes haemodynamically relevant with enhanced right heart overload due to significant left-to-right-shunting. Purpose This study aimed to evaluate pre- and periprocedural factors that may favour persistence and haemodynamic relevance of iASD in patients after PMVR. Methods In 2015, 75 consecutive patients with severe MR (age 74.8±10.5y) and following PMVR were enrolled. After 12 months, 57 patients completed their follow up (FU) including clinical conditions, transthoracic echocardiography (TTE), and cardiovascular magnetic resonance (CMR) whenever feasible. We evaluated the impact of comorbidities as well as intraprocedural, haemodynamic and functional characteristics that may favour persistence of iASD by multivariate analysis. Haemodynamic relevance of iASD was defined as right heart overload with predominantly significant enlargement of the right atrium (RA), impairment of right heart function as defined by fractional area shortening (FAC), and ratio of pulmonary to systemic blood flow (Qp/Qs&gt;1) when available. Results 18 out of 57 patients (32%) showed a persistent iASD (+iASD), being associated with a specific combination of comorbidities as well as pre-procedural and periprocedural factors that can be summarised by a multifactorial iASD risk calculator (+iASD vs. -iASD: 6.3±2.9 vs. 3.9±2.7; p=0.0058). 11 iASD (61%) became haemodynamically relevant (+hd iASD) with a significant right heart overload (RA area +hd iASD vs. -hd iASD: baseline 23.1±4.1 vs. 23.2±4.3; FU 30.7±6.3 vs. 20.1±4.6; p&lt;0.0001), reduced RV function (FAC +hd iASD vs. -hd iASD: baseline 41.0±10.3 vs. 29.9±7.2; FU 25.3±7.2 vs. 29.1±13.2; p&lt;0.0156) and left-to-right shunting (Qp/Qs -iASD vs. +hd iASD vs. -hd iASD: 1.0±0.3 vs. 1.7±0.4 vs. 0.8±0.1 L/min; p=0.0011). Conclusion This study shows for the first time, that persistence of iASD can be predicted by pre- and periprocedural factors using a risk calculator that may additionally guide careful follow up imaging and therapeutic action after PMVR to avoid development of progressive heart failure.

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

BackgroundPersistent 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. MethodsA 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. ResultsPersistent 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. ConclusionsApproximately 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.

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

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 1year 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. After a first PVI with cryoballoon, 102 patients (64 ± 10years, 64% male) underwent long-term clinical follow-up and comprehensive transthoracic and transesophageal echocardiographic study. 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 1cm/s decrease, p = 0.002). 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 15.5months after the second-generation CB ablation, and the atrial septal angle might aid in predicting persistent iASDs.

Persistence of iatrogenic atrial septal defect after interventional mitral valve repair with the MitraClip system: a note of caution.

The purpose of this study was to investigate the persistence rates of iatrogenic atrial septal defect (iASD) after interventional edge-to-edge repair with serial transesophageal echocardiography examinations and close clinical follow-up (FU). Transcatheter mitral valve repair (TMVR) with the MitraClip system (Abbott Vascular, Abbott Park, Illinois) is a therapeutic alternative to surgery in selected high-risk patients. Clip placement requires interatrial transseptal puncture and meticulous manipulation of the steerable sheath. The persistence of iASD after MitraClip procedures and its clinical relevance is unknown. A total of 66 patients (76.7% male, mean age 77.1 ± 7.9 years) with symptomatic mitral regurgitation (MR) at prohibitive surgical risk (EuroSCORE II 10.1 ± 6.1%) underwent MitraClip procedures and completed 6 months of FU. Transesophageal echocardiography after FU showed persistent iASD in 50% of cases. Patients with iASD did not significantly differ from patients without ASD concerning baseline characteristics, New York Heart Association functional class, severity of MR, and acute procedural success rates (p > 0.05). When comparing procedural details and hemodynamic measures between groups, MitraClip procedures took longer in patients without iASD (82.4 ± 39.7 min vs. 68.9 ± 45.5 min; p = 0.05), and echocardiography after FU showed less decrease of systolic pulmonary artery pressures in the iASD group (-1.6 ± 14.1 mm Hg vs. 9.3 ± 17.4 mm Hg; p = 0.02). Clinically, patients with iASD presented more often with New York Heart Association functional classes >II after FU (57% vs. 30%; p = 0.04), showed higher levels of N-terminal pro-brain natriuretic peptide (6,667.3 ± 7,363.9 ng/dl vs. 4,835.9 ± 6,681.7 ng/dl; p = 0.05), and had less improvement in 6-min walking distances (20.8 ± 107.4 m vs. 114.6 ± 116.4 m; p = 0.001). Patients with iASD showed higher death rates during 6 months (16.6% vs. 3.3%; p = 0.05). Cox regression analysis found that only persistence of iASD (p = 0.04) was associated with 6-month survival. The persistence rate of 50% iASD after MitraClip procedures is considerably high. Persistent interatrial shunting was associated with worse clinical outcomes and increased mortality. Further studies are warranted to investigate if persistent interatrial shunting is the mediator or marker of advanced disease in these patients.

RIGHT HEART FAILURE FROM PERSISTENT IATROGENIC ATRIAL SEPTAL DEFECT FOLLOWING ATRIAL FIBRILLATION ABLATION

Persistent iatrogenic atrial septal defect (iASD) has been reported in patients with a transseptal puncture performed for access to the left atrium. Majority of these resolve spontaneously and their clinical significance remains unknown. Here, we report a rare case of a symptomatic, persistent iASD

Prevalence and echocardiographic features of iatrogenic atrial septal defect after catheter‐based mitral valve repair with the mitraclip system

Review the prevalence, echocardiographic features and potential predictors of iatrogenic ASD (iASD) created with the MitraClip guiding catheter. Catheter-based repair of mitral regurgitation (MR) with the MitraClip device (Abbott Vascular, Menlo Park, CA), is performed through a 22-French transseptal guiding catheter. The echocardiographic prevalence of iASDs after the MitraClip procedure has not been reported. Thirty subjects undergoing MitraClip repair during the roll-in phase of the EVEREST II randomized trial who had baseline, 30 day, 6 and 12 month transthoracic echocardiograms (TTEs) available for review were included. Patients who underwent surgery for MR within the first 12 months were excluded. Residual iASD size, right ventricular (RV) size, left atrial (LA) volume, and tricuspid/MR grade were quantified. iASDs were found at 12 months in 8 patients (27%) with a mean diameter of 6.6 ± 3.1 mm. Subjects with iASD at 12 months had more residual MR, increased TR and a trend toward larger LA volumes than non-iASD patients. 83% of non-ASD patients were free from MR > 2+ at 12 mos. vs. 38% of those with iASD (p=0.016). There were no other significant associations between clinical and echocardiographic variables and the persistence of iASD. After MitraClip repair, persistent iASDs occur at a rate comparable to reports after other transseptal interventional procedures and do not appear hemodynamically significant. Patients with persistent iASDs had less MR reduction at 12-months and a trend toward larger LA volumes, suggesting that increased LA pressure may be a mechanism for persistent iASD.

Iatrogenic atrial septal defect after catheter ablation of atrial fibrillation: do we have to worry?

Catheter ablation for treatment of atrial fibrillation has become a more and more important curative treatment option over the past decade. Several randomized studies have shown that catheter ablation is clearly superior to antiarrhythmic drug treatment in patients with paroxysmal and persistent atrial fibrillation.1–3 However, the procedure is highly invasive and is associated with relatively infrequent, but at times severe procedural complications.4–6 Among these complications, thromboembolic events may occur peri-procedurally or post-interventionally.6 Although never explicitly assessed, persistent iatrogenic atrial septal defects (iASD) after transseptal access may provide a cause for such thromboembolic events during long-term follow-up through the route of paradoxic embolism. Is there a rationale for this concern? Yes, we believe there is a rationale. Clearly, the amount of damage to the interatrial septum and the risk of persistent iASD differ and depend on the tools, technologies, and approaches used for catheter ablation. In general, for simultaneous multiple left atrial access, two main techniques have to be distinguished. First, a double puncture, double transseptal technique, where two sheaths are being advanced over the interatrial septum through two distinctly different puncture sites. Second, a single puncture, double transseptal technique where two sheaths are advanced over the interatrial septum through a single dilated puncture site. There is interesting data on … *Corresponding author. Email: philipp.sommer{at}herzzentrum-leipzig.de

Persistent iatrogenic atrial septal defect after a single-puncture, double-transseptal approach for pulmonary vein isolation using a remote robotic navigation system: results from a prospective study

Persistent iatrogenic atrial septal defect (iASD) after transseptal puncture for pulmonary vein isolation (PVI) has been described recently as a complication of PVI. No data exists evaluating systematically the incidence and clinical implications of iASDs after PVI using a remote robotic navigation system (RNS) with sheaths with a distinct larger outer diameter. In this prospective study, 40 patients with either paroxysmal (n = 22, 55%) or persistent symptomatic atrial fibrillation were treated with circumferential PVI using an RNS. In all patients, a single-puncture, double-transseptal approach was used to access the left atrium. Transoesophageal echocardiography was performed before and the day after PVI as well as after a 3 and 6 months follow-up (FU). The day after ablation an iASD was detected in 38 of 40 (95%) patients with a mean diameter of 3.45 +/- 1.5 mm. At 6-month FU, the iASDs were closed in 30 of 39 (78.9%) patients. During the 6-month FU period, no patient died or suffered from cerebral or cardiac embolism. After a single-puncture, double-transseptal approach for PVI using the RNS, iASDs show a high spontaneous closure rate of 78.9% after a 6-month FU period. Persistent iASDs following PVI with the RNS are not associated with an increased rate of paradoxical embolism or with relevant shunting.