Real-time imaging for transcatheter closure of atrial septal defects

Phase contrast cardiac magnetic resonance imaging versus transoesophageal echocardiography for the evaluation of feasibility for transcatheter closure of atrial septal defects

Background

This prospective study was aimed at comparing phase contrast cardiac magnetic resonance imaging (PC-CMR) with 2D transoesophageal echocardiography (TEE) for determining potential candidature for transcatheter closure in ostium secundum ASD (OS-ASD) patients. We included consecutive adult patients with OS-ASD for the evaluation of feasibility for transcatheter closure using 2D-TEE and PC-CMR over a period of 2 years. Patients who fulfilled the conventional criteria for transcatheter closure, i.e. maximum ASD diameter ≤ 34 mm, adequate rims (≥ 5 mm, except for anterosuperior rim), and normal pulmonary venous drainage on both imaging modalities, were taken for device closure. In patients where there was discrepancy in the measurements of ASD diameter or rim size, making them eligible for device closure on one imaging modality and ineligible on the other hand, provisional device closure was attempted. All patients who underwent transcatheter closure were followed up to 6 months to rule out any complications.

Results

A total of 58 patients (mean age 35.93 ± 10.59 years) were enrolled in the study. Overall, there was significant positive correlation between 2D-TEE and CMR measurements of maximal ASD diameter and rim size (p < 0.001). However, TEE significantly underestimated maximal ASD diameter and posteroinferior rim size in comparison with CMR (p = 0.013 and p = 0.023, respectively). 46 (79.3%) patients were suitable for transcatheter closure on CMR, while 44 (75.9%) were eligible on TEE. Transcatheter closure was attempted in 48 patients based on imaging findings and was successful in 46 (95.8%) patients. Device closure was unsuccessful in 2 patients with defect size < 34 mm on TEE but > 34 mm on CMR. Among 7 patients with deficient posteroinferior rim on TEE, 5 had sufficient rim on CMR and underwent successful transcatheter closure. CMR detected anomalous pulmonary venous drainage in one patient which was missed on TEE, hence excluding the patient from transcatheter closure. Mean device size was 28.3 ± 7.4 mm and correlated more strongly with the defect dimensions on PC-CMR (r = 0.85, p < 0.001) compared to TEE (r = 0.71, p = 0.02).

Conclusions

PC-CMR may to be superior to 2D-TEE for the preprocedural planning and feasibility assessment for transcatheter closure in adult patients with ostium secundum ASD.

Clinical advantage of real-time three-dimensional transesophageal echocardiography for transcatheter closure of multiple atrial septal defects

This study sought to evaluate the usefulness of real-time three-dimensional (3D) transesophageal echocardiography (TEE) to guide the repair of multiple atrial septal defects (ASDs). Of 212 consecutive patients with secundum ASD who were scheduled for transcatheter closure of their ASDs, 27 had multiple ASDs. These patients underwent two-dimensional (2D) transthoracic echocardiography, 2D TEE, and 3D TEE. Overall, 18 patients had two defects, and 9 patients had three or more defects. The latter group included three patients with multi-fenestrated defects. Optimal 3D images were obtained in 93 % of the patients. In patients with two defects, information on the positional relation of the defects was obtained using 2D TEE and 3D TEE in 71 and 94 % of patients, respectively (P = 0.22). The positional relations of the defects could not be evaluated with 2D TEE in patients with three or more defects, whereas it could be evaluated with 3D TEE in all of these patients (0 vs. 100 %, P = 0.008). In all patients, 3D TEE proved superior to 2D TEE for providing sufficient information (96 vs. 48 %, P = 0.002). Procedural success was obtained in 26 patients (96.3 %), without complications. Transcatheter closure of multiple ASDs under 3D TEE guidance is effective and safe. Real-time 3D TEE can provide useful information regarding complex ASD morphology. It can thus contribute to developing a successful treatment strategy, especially in patients with three or more defects.