Right-to-left shunt via iatrogenic atrial septal defect requiring emergency surgical repair following cryoballoon atrial fibrillation ablation in a patient with arrhythmogenic right ventricular cardiomyopathy

An 81-year-old woman with arrhythmogenic right ventricular cardiomyopathy underwent catheter ablation for atrial fibrillation and atrial flutter. Hypoxemia refractory to the administration of oxygen was seen after transseptal puncture. Transthoracic echocardiography revealed right to left shunt via an iatrogenic atrial septal defect (IASD) that was increased by tricuspid regurgitation flow. Her hypoxemia improved after IASD occlusion with the inflation of a venogram balloon catheter. Emergent surgical IASD closure was successfully performed. IASD after transseptal puncture for atrial fibrillation ablation infrequently causes severe complications that require emergent repair.

Learning objective

Some cases requiring iatrogenic atrial septal defect (IASD) closure after atrial fibrillation (AF) ablation have been reported. We describe the case of an arrhythmogenic right ventricular cardiomyopathy patient with right to left shunt via an IASD which required emergent surgical repair after AF ablation. Right to left shunt after trans-septal puncture is rare, however it can be an emergent life-threatening complication. IASD occlusion with venogram balloon catheter is helpful for the diagnosis and the short-term solution.

Iatrogenic Atrial Septal Defect Requiring Transcatheter Closure Following Transcatheter Mitral Valve Repair

BACKGROUND

Transcatheter mitral valve repair with the MitraClip system has been established in selected high-risk patients. The MitraClip procedure results in a relatively large iatrogenic atrial septal defect (iASD). This study aimed to investigate the prevalence and clinical course of iASD requiring transcatheter closure following the MitraClip procedure.Methods and Results: This study was conducted at all 59 institutions that perform transcatheter mitral valve repair with the MitraClip system in Japan. The data of patients on whom transcatheter iASD closure was performed were collected. Of the 2,722 patients who underwent the MitraClip procedure, 30 (1%) required transcatheter iASD closure. The maximum iASD size was 9±4 mm (range, 3-18 mm). The common clinical course of transcatheter iASD closure was hypoxemia with right-to-left shunt or right-sided heart failure with left-to-right shunt. Of the 30 patients, 22 (73%) required transcatheter closure within 24 h following the MitraClip procedure, including 12 with hypoxemia and 5 with right-sided heart failure complicated with cardiogenic shock. Of the 5 patients, 2 required mechanical circulatory support devices. Twenty-one patients immediately underwent transcatheter iASD closure, and hemodynamic deteriorations were resolved; however, 1 patient died without having undergone transcatheter closure.

CONCLUSIONS

Transcatheter iASD closure was required in 1% of patients who underwent the MitraClip procedure. Many of these patients immediately underwent transcatheter iASD closure because of hypoxemia with right-to-left shunt or right-sided heart failure with left-to-right shunt.

Heart failure caused by iatrogenic atrial septal defect after cryoballoon ablation for atrial fibrillation

An 83-year-old man with no structural heart disease underwent pulmonary vein isolation (PVI) for symptomatic paroxysmal atrial fibrillation (AF). The PVI was successfully performed by cryoballoon ablation with a single transseptal puncture. A 12Fr deflectable sheath and an 8.5Fr long sheath crossed the interatrial septum via the same puncture site. Five months after PVI, the patient was readmitted because of heart failure and recurrence of AF. The echocardiogram showed a large (10.7 × 5.8 mm) iatrogenic atrial septal defect (IASD) at the previous puncture site. Both right-to-left and left-to-right shunts were observed during systole and diastole, respectively. Despite the initiation of optimal medical therapy for heart failure, symptoms were not completely controlled and IASD remained 11 months after PVI. Eventually, he received multiple additional PVI for recurrence of AF and percutaneous transcatheter closure (13 mm disc for 10.9 × 8.9 mm- IASD), then heart failure was controlled with the improvement of the right atrial and ventricular size. Although the induction of heart failure by IASD after PVI is rare, it should be noted as one of the causes, especially after cryoballoon ablation with simultaneous mapping catheter insertion via a single transseptal puncture. <Learning objective: Pulmonary vein isolation (PVI) is the established therapy for atrial fibrillation; however, it may cause several complications including iatrogenic atrial septal defect (IASD). IASD is less apparent than other complications, therefore it may be underrecognized. Although the induction of heart failure by IASD after PVI is rare, it should be noted as one of the causes, especially after cryoballoon ablation with simultaneous circular mapping catheter insertion via a single transseptal puncture.>.

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 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.

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.

Transcatheter closure of a complex atrial septal defect after occluder device embolization

Percutaneous closure is nowadays considered the treatment of choice of ostium secundum atrial septal defects (ASD). However, transcatheter closure can be highly challenging when we face an ASD with complex morphological features. The combination of different imaging modalities can be very helpful. This case shows the great value of using both intracardiac and real time 3D transesophageal echocardiography for the percutaneous closure of a complex iatrogenic ASD after device embolization.

Haemodynamic and functional consequences of the iatrogenic atrial septal defect following Mitraclip therapy

Percutaneous MitraClip placement for treatment of severe mitral regurgitation in high surgical risk patients is a commonly performed procedure and requires a transseptal puncture to reach the left atrium. The resulting iatrogenic atrial septal defect (iASD) is not routinely closed, yet the haemodynamic and functional consequences of a persisting defect are not fully understood. Despite positive effects such as acute left atrial pressure relief, persisting iASDs are associated with negative consequences, namely significant bidirectional shunting and subsequent worse clinical outcome. Percutaneous closure of the iASD may therefore be desirable in selected cases. In this review we discuss the available literature on this matter.