Atrial Fibrillation After Patent Foramen Ovale Closure: Incidence, Pathophysiology, and Management

This comprehensive review explores the incidence, pathophysiology, and management of atrial fibrillation (AF) following percutaneous closure of patent foramen ovale (PFO). Although AF is considered a common adverse event post PFO closure, its incidence, estimated at <5%, varies based on monitoring methods. The review delves into the challenging task of precisely estimating AF incidence, given subclinical AF and diverse diagnostic approaches. Notably, a temporal pattern emerges, with peak incidence around the 14th day after closure and a subsequent decline after the 45th day, mimicking general population AF trends. The pathophysiological mechanisms behind post PFO closure AF remain elusive, with proposed factors including local irritation, device-related interference, tissue stretch, and nickel hypersensitivity. Management considerations encompass rhythm control, with flecainide showing promise, and anticoagulation tailored to individual risk profiles. The authors advocate for a personalized approach, weighing factors like age, comorbidities, and device characteristics. Notably, postclosure AF is generally considered benign, often resolving spontaneously within 45 days, minimizing thromboembolic risks. Further studies are required to refine understanding and provide evidence-based guidelines.

TAVI for low-flow, low-gradient severe aortic stenosis: impact on outcome

Background

Several factors have been identified as predictors of events after transcatheter aortic valve implantation (TAVI) but the impact of transaortic flow (F) and mean transaortic gradient (MG) upon outcomes is controversial. This study aimed to clarify the prognostic role of low FL and low MG after TAVI.

Methods

Patients with severe and symptomatic aortic stenosis [effective orifice area (EOA) ≤1cm2], referred for TAVR at our institution were consecutively enrolled. Given the aim of this analysis, patients were divided according to F and MG into four groups: 1) LF-LG Patients with low flow (SVi &lt;35ml/m2) and low mean gradient (MG &lt;40mmHg), 2) NF-LG Patients with normal flow (SVi ≥35ml/m2) and low mean gradient (MG &lt;40mmHg), 3) LF-HG Patients with low flow (SVi &lt;35ml/m2) and high mean gradient (MG ≥40mmHg) and 4) NF-HG patients with normal flow (SVi ≥35ml/m2) and high mean gradient (MG ≥40mmHg). Prospectively collected demographic, laboratory and echocardiographic data were retrospectively analyzed. One-year outcomes were compared between the 4 groups of patients. Primary clinical endpoint was all-cause mortality at long term follow up, as defined by the criteria proposed by the Valve Academic Research Consortium2.

Results

In total 255 patients undergoing TAVI at our institution were included in our study: 35 (13.7%) patients with LF-LG, 17 (6.7%) with NF-LG, 108 (42.4%) with LF-HG and 95 (37.3%) with NF-HG. There was a statistically significant difference in gender distribution between the groups with most females being represented in the NF-HG group (64.2%) vs the LF-LG (31.4%), the NF-LG (47.1%) or the LF-HG group (50.9%) (p=0.008). Moreover, LF-LG patients were younger than NF-LG, LF-HG or NF-HG patients (ANOVA, p=0.037). There was a greater prevalence of prior myocardial infarction (MI) in the LF-LG group (34.5%) vs 20% in the NF-LG, 16.1% in the LF-HG and 20.2% in the NF-HG group (p=0.005). At 1 year follow up there were no statistically significant differences in major vascular complication, major bleeding complication or permanent pacemaker implantation rates between the groups, (all p&gt;0.05). At a median follow up of 36 months IQR (17, 56) all-cause mortality was significantly higher in the LF-LG group as opposed to the NF-LG, LF-HG and NF-HG groups (77.41% vs 60% vs 55.67% vs 46.15% respectively, p=0.005). These results were confirmed by multivariate logistic regression analysis, as the combination of low flow and low mean gradient emerged as the strongest long term all cause mortality predictor (HR: 5.39, 95% confidence intervals: 1.72–16.83; p=0.004)

Conclusion

Combination of low flow and low mean transaortic gradient portends a worse prognosis after TAVI.

Funding Acknowledgement

Type of funding sources: None.

Impact of significant preprocedural mitral regurgitation on mortality after transcatheter aortic valve implantation

Background

Mitral regurgitation (MR) is commonly encountered in patients with severe aortic stenosis scheduled for transcatheter aortic valve implantation (TAVI). The presence of significant pre-procedural MR, however, has not been accounted in pivotal trials of TAVI and data regarding its independent impact on outcome are contradictory.

Methods

Patients with severe and symptomatic aortic stenosis [effective orifice area (EOA) ≤1cm2] referred for TAVI at our institution were consecutively enrolled. Prospectively collected demographic, laboratory and echocardiographic data were retrospectively analysed. Patients were stratified into two groups according to MR severity: ≤ grade 1 were defined as non-significant and ≥ grade 2 as significant. Change in MR was determined by comparison between baseline and 30-day echocardiogram. Primary clinical endpoint was all-cause mortality, as defined by the criteria proposed by the Valve Academic Research Consortium2.

Results

A total of 331 consecutive patients were enrolled in the study: 247 (74.6%) had non-significant MR and 84 (25.4%) patients had significant MR at baseline. Patients with significant pre-procedural MR had lower baseline ejection fraction (47.7±10.4% versus 51.2±8.4%, p=0.002), higher pulmonary artery systolic pressure (52±14.3mmHg versus 42.5±11.1mmHg, p&lt;0.0001) and higher rates of moderate or severe tricuspid regurgitation (TR) (50% versus 19.4%) compared to patients with non-significant MR. Of all patients, mitral regurgitation improved in 9.5%, remained the same in 83.9%, and worsened in 6.6% 30 days after TAVR. In a multivariable analysis, pre-procedural TR severity was predictor of improved mitral regurgitation [OR 3.003,(95% CI 1.216–7.417, p=0.017)].

The primary clinical end point occurred in 44.7% of all patients during a follow-up period of 36.6.±25.9 months. Patients with significant pre-procedural MR had significantly higher rates of all-cause mortality compared to patients with non-significant (54.7% and 41.3%, respectively; log rank p=0.015). Performing a multivariable analysis demonstrated that preprocedural MR severity could independently predict cumulative mortality [OR 0.480, (95% CI 0.247–0.932, p=0.03)].

Conclusion

Significant pre-procedural MR is common in patients undergoing TAVI and is associated with increased all-cause mortality. TAVI is associated with a significant improvement in MR, especially in severe types. These data provide new insights in the crucial role of mitral regurgitation in the risk assessment of TAVI candidates.

Funding Acknowledgement

Type of funding sources: None.

Effect of concomitant atrioventricular valve regurgitation on the outcome after transcatheter aortic-valve implantation

Background

Many patients undergoing transcatheter aortic valve implantation (TAVI) have concomitant mitral regurgitation (MR) of moderate grade or more. The impact of coexistent tricuspid regurgitation (TR) remains to be determined.

Methods

Patients with severe and symptomatic aortic stenosis [effective orifice area (EOA)≤1cm2] referred for TAVI at our institution were consecutively enrolled. Prospectively collected demographic, laboratory and echocardiographic data were retrospectively analysed. Patients were divided into 4 groups according to MR and TR severity pre-procedurally: no/mild MR and TR, moderate/severe MR, moderate/severe TR, moderate/severe MR and TR. Primary clinical endpoint was all-cause mortality, as defined by the criteria proposed by the Valve Academic Research Consortium2.

Results

A total of 244 consecutive patients were enrolled in the study: 148 (60.7%) patients no/mild MR and TR, 32 (13.1%) moderate/severe MR, 35 (14.3%) moderate/severe TR, 29 (11.9%) moderate/severe MR and TR pre-procedurally. There was significant difference in pre-procedural pulmonary artery systolic pressure (PASP) among groups (no/mild MR and TR: 40.8±10 mmHg, moderate/severe MR: 46.6±11.2 mmHg, moderate/severe TR: 49.9±13mmHg, moderate/severe MR and TR: 59.8±15.2mmHg, p&lt;0.0001). The Kaplan–Meier curves for 2 year mortality showed that the severity of TR was associated with poor survival. Interestingly, patients with moderate/severe MR and TR had the worse survival (no/mild MR and TR (91.2%), moderate/severe MR (78.1%), moderate/severe TR (62.9%), moderate/severe MR and TR (62.1%), p&lt;0.0001).

Conclusion

The presence of concomitant moderate or severe mitral and tricuspid valve regurgitation was associated with the higher mortality. This suggests that a thorough evaluation of the mechanisms underlying concomitant mitral and tricuspid valve regurgitation should be performed to determine the best strategy for avoiding TAVI-related futility.

Funding Acknowledgement

Type of funding sources: None.