Left atrial pressure is associated with iatrogenic atrial septal defect after mitral valve clip

Abstract

ObjectivesMitral valve (MV) clip procedure requires interatrial trans-septal puncture to access the left atrium (LA). Iatrogenic atrial septal defect (iASD) is not uncommon and may remain for a while. However, haemodynamic and echocardiographic determinants of persistent iASD are not well investigated. We sought to find haemodynamic and echocardiographic determinants of iASD after MV clip.MethodsA total of 131 patients with grades 3 to 4+ mitral regurgitation who underwent MitraClip and completed invasive haemodynamic measurement, baseline, 1 month and approximately 12 months of transthoracic echocardiography (TTE) follow-up were retrospectively reviewed.ResultsTTE at 1 month showed persistent iASD in 57% (1M-iASD). Mean LA pressure after clip was significantly higher in patients with 1M-iASD than patients without 1M-iASD (17±6 mm Hg vs 15±5 mm Hg, p=0.01). Among patients with 1M-iASD, 24 patients (35%) had persistent iASD at 12 months (12M-iASD). Mean LA pressure after clip was significantly higher in patients with 12M-iASD than patients without 12M-iASD (19±6 mm Hg vs 16±6 mm Hg, p=0.04). Patients with 12M-iASD did not significantly differ from patients without 12M-iASD in terms of right heart enlargement, estimated systolic pulmonary artery pressure, New York Heart Association functional class and brain natriuretic peptide at 12 months. Logistic regression analysis, however, showed that mean LA pressure after clip was significantly associated with persistent iASD at 12 months in patients with 1M-iASD even after adjustment for cardiac index after clip and the prevalence of mitral regurgitation ≥3+ at 12 months (OR 1.10 per 1 mm Hg, 95% CI 1.01 to 1.21, p=0.04).ConclusionsElevated LA pressure after MV clip was associated with persistent iASD.

Iatrogenic atrial septal defect following the MitraClip procedure: A state‐of‐the‐art review

“…Patients who had completed baseline, 1 and 12 months of TTE follow‐up were included. At 1 month, TTE showed persistent iASDs in 57% of patients and 19% at 12 months 11 . Similarly, in a separate study of 96 patients that underwent the MitraClip procedure, 24% of cases were found to have persistent iASDs at 12 months as evidence by TTE imaging 12 .…”

“…However, no difference in right heart enlargement, estimated pulmonary artery systolic pressure, New York Heart Class (NYHA), and brain natriuretic peptide (BNP) levels at 12 months was noted between the two groups. Elevated LA pressure after MitraClip was associated with persistent iASDs but no clinical impact was established 11 …”

“…At 30 days, up to 82% of patients were noted to have residual iASDs using TEE, decreasing to 50% at 6 months. At 12 months follow‐up, all available studies used TTE imaging which showed residual iASD in 10–27% of patients 7,10‐12,14 . Table 1 illustrates the retrospective studies identified that assess the prevalence and outcomes related to iASDs following the MitraClip procedure.…”

“…Smith et al suggest that high LA pressure likely contributes to the patency of the iASD 10 . Similarly, Ikenaga et al found that patients with persistent iASDs at 12 months had a significantly higher mean LA pressure than patients without the iASDs 11 . Saitoh et al did not assess for hemodynamics but the authors report that the larger iASDs did not close 14 .…”

Heartbeat: Diagnosis of subclinical atrial fibrillation by physicians and patients

“…Other interesting papers in this issue include the study by Ikenaga and colleagues6 showing that, in patients with mitral regurgitation undergoing transcatheter edge-to-edge mitral valve repair, persistence at 12 months of the iatrogenic atrial septal defect (from the procedural transeptal puncture) is related to elevated left atrial pressure, even after adjustment for cardiac index and residual mitral regurgitation.…”