Patent foramen Ovale-related paradoxical embolism after noncardiac surgery

Patent foramen ovale (PFO) is a remnant of the fetal circulation that remains in a significant portion of the adult population, predisposing to a higher risk of stroke. This risk is further elevated in the postoperative hypercoagulative period. Here we present a case where a patient underwent a total knee arthroplasty and presented with right-sided hemiparesis on post-operative day 2. Subsequently, the patient underwent percutaneous PFO closure with a 25-mm Amplatzer PFO Occluder (Abbott; Chicago, IL, USA). The patient has not had a stroke since the PFO closure. Recent randomized trials have demonstrated superiority of percutaneous PFO closure over standard-of-care medical therapy for secondary prevention of PFO-associated stroke. Since post-operative PFO-associated stroke is under-recognized in clinical practice, further large-cohort studies are needed to evaluate whether PFO screening and device closure would decrease post-operative stroke risk for noncardiac surgeries.

Learning Objective

Patent foramen ovale (PFO) is a remnant of the fetal circulation commonly found in the adult population, which can increase the risk of stroke. Stroke is a complication of PFO, yet closure of this remnant only occurs on a specific case-by-case basis. Further research in this area is required to determine whether a larger population would benefit from PFO closure.

Effects and clinical implications of sacubitril/valsartan on left ventricular reverse remodeling in patients affected by chronic heart failure: A 24-month follow-up

Background

Compared to angiotensin inhibition, angiotensin-neprilysin "blockade" improves mortality and reduces hospitalizations in patients with heart failure (HF) with reduced ejection fraction (EF). Sacubitril/valsartan is known to influence left ventricular (LV) reverse remodeling with systolic function improvement, although underlying mechanisms remain partially unclear. Our objectives were to evaluate whether sacubitril/valsartan promotes LV remodeling and improves LV ejection fraction (LVEF) (above the 35% threshold by echocardiographic evaluation) and to identify predictors of reverse remodeling in a real-world setting.

Methods

New York Heart Association (NYHA) class II-III patients with EF ≤ 35% were consecutively enrolled. All patients were on optimal medical therapy on the initiation of sacubitril/valsartan therapy. Full clinical and multi-parametric echocardiographic evaluation, electrocardiogram, and laboratory tests were performed at baseline and after 3, 6, 12, and 24 months.

Results

In total, 69 patients were recruited from July 2016 to August 2018. Reverse remodeling was observed in 57.7% (30/52) of patients, occurring within 3, 6, 12, and 24 months in 2, 11, 13, and 4 patients, respectively. Twenty-four (46%) patients showed LVEF improvement above the threshold of 35% during follow-up, occurring in 1, 10, 9, and 4 patients within 3, 6, 12, and 24 months, respectively. Primitive dilated cardiomyopathy and female gender were identified as significant predictors of reverse remodeling. NYHA class was improved in both remodeling and non-remodeling patients.

Conclusion

Sacubitril/valsartan promotes favorable cardiac remodeling and significantly improves LVEF in a significant proportion of HF patients within 24 months, both in NYHA class II and III patients with HF.

Left atrial, pulmonary vein, and left atrial appendage anatomy in Indigenous individuals: Implications for atrial fibrillation

Background

Indigenous Australians experience a greater burden of AF. Whether this is in-part due to differences in arrhythmogenic structures that appear to contribute to AF differences amongst other ethnicities is not known.

Methods

We studied forty individuals matched for ethnicity and other AF risk factors. Computed tomography imaging was used to characterise left atrial (LA), pulmonary vein (PV), and left atrial appendage (LAA) anatomy.

Results

There were no significant differences in LA diameters or volumes between Indigenous and non-Indigenous Australians. Similarly, we could not detect any consistent differences in PV number, morphology, diameters, or ostial characteristics according to ethnicity. LAA analyses suggested that Indigenous Australians may have a greater proportion of non chickenwing LAA type, and a tendency for eccentric, oval-shaped LAA ostia; however, there were no other differences seen with regards to LAA volume or depth. Indexed values for LA, PV and LAA anatomy corrected for body size were broadly similar.

Conclusions

In a cohort of individuals matched for AF risk factors, we could find no strong evidence of ethnic differences in LA, PV, and LAA characteristics that may explain a predisposition of Indigenous Australians for atrial arrhythmogenesis. These findings, in conjunction with our previous data showing highly prevalent cardiometabolic risk factors in Indigenous Australians with AF, suggest that it is these conditions that are more likely responsible for the AF substrate in these individuals. Continued efforts should therefore be directed towards risk factor management in an attempt to prevent and minimise the effects of AF in Indigenous Australians.

Efficacy of ablation at the anteroseptal line for the treatment of perimitral flutter

Background

Left atrial flutter following atrial fibrillation (AF) ablation is increasingly common and difficult to treat. We evaluated the safety and efficacy of ablation of the anteroseptal line connecting the right superior pulmonary vein (RSPV) to the anteroseptal mitral annulus (MA) for the treatment of perimitral flutter (PMF).

Methods

We systematically studied patients who were previously treated with AF ablation and who presented to the electrophysiology laboratory with atrial tachyarrhythmias between January 2000 and July 2010. The diagnosis of PMF was confirmed by activation mapping and/or entrainment. After re-isolation of any recovered pulmonary vein, a linear radiofrequency (RF) ablation was performed on the line that connected the RSPV to the anteroseptal MA. In this analysis, we included only patients who were treated with an anteroseptal line for their PMF.

Results

Ablation was performed at the anteroseptal line in 27 PMF patients (63±13 years; 9 women) who had undergone prior ablation for paroxysmal (n=3) or persistent (n=24) AF, using electroanatomic activation mapping (70% CARTO, 30% NavX). The anteroseptal ablation line was effective in 22/27 (81.5%) patients in the acute-care setting. Termination of AF to sinus rhythm occurred in 15/22 (68.2%) patients, and 7/22 (31.8%) patients׳ AF converted to another right or left atrial flutter. At the 6-month follow-up, 20% of patients demonstrated recurrent left atrial tachyarrhythmia. Only one patient required repeat ablation, and the remaining patients׳ condition was controlled with antiarrhythmic medications. No major procedural complications or heart block occurred.

Conclusion

Ablation at the left atrial anteroseptal line is safe and efficacious for the treatment of PMF. Unlike ablation at the traditional mitral isthmus line, ablation at the left atrial anteroseptal line does not require ablation in the coronary sinus.