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.

Complications Following MitraClip Implantation

Purpose of Review To provide a detailed overview of complications associated with MitraClip therapy and its development over time with the aim to alert physicians for early recognition of complications and to offer treatment strategies for each complication, if possible. Recent Findings The MitraClip system (MC) is the leading transcatheter technique to treat mitral regurgitation (MR) and has been established as a safe procedure with very low adverse event rates compared to mitral surgery at intermediate to high risk or in secondary MR. Lately, the fourth MC generation has been launched with novel technical features to facilitate device handling, decrease complication rates, and allow the treatment of even complex lesions. Summary Although the complication rate is low, adverse events are associated with increased morbidity and mortality. The most common complications are bleeding, acute kidney failure, procedure-induced mitral stenosis, and an iatrogenic atrial septal defect with unknown clinical impact.

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.