Melduni, Rowlens M.

Objective Previous studies have postulated a causal role of patent foramen ovale (PFO) in the aetiology of embolic stroke in the general population. We hypothesised that the presence of concomitant PFO and atrial fibrillation (AF) will add incremental risk of ischaemic stroke to that linked to AF alone. Methods We analysed data on 3069 consecutive patients (mean age 69.4±12.2 years; 67.1% men) undergoing transoesophageal echocardiography-guided electrical cardioversion (ECV) for AF between May 2000 and March 2012. PFO was identified by colour Doppler and agitated saline contrast study. All patients were followed up after ECV for first documentation of ischaemic stroke. Outcomes were compared using Cox regression models. Results The prevalence of PFO was 20.0% and the shunt direction was left-to-right in the majority of patients (71.4%). Patients with PFO had a higher frequency of obstructive sleep apnoea (21.7% vs 17.1%, p=0.01) and higher mean peak left atrial appendage emptying velocity (38.3±21.8 vs 36.1±20.4 cm/s; p=0.04) compared with those without PFO. Otherwise, baseline characteristics were similar between groups. During a mean follow-up period of 7.3±4.6 years, 214 patients (7.0%) had ischaemic stroke. Multivariable analysis showed no significant association between PFO and ischaemic stroke (HR, 0.82 (95% CI 0.57 to 1.18)). PFO shunt direction was strongly associated with stroke: HR, 1.91 (95% CI 1.16 to 3.16) for right-to-left shunt and HR, 0.58 (95% CI 0.36 to 0.93) for left-to-right shunt. Conclusions The presence of concurrent PFO in this largely anticoagulated group of patients with AF was not associated with increased risk of ischaemic stroke.

AbstractWe describe a case of a mass‐like echocardiographic density on a mechanical prosthetic aortic valve. We initially suspected a thrombus vs vegetation on transthoracic echocardiography, but after transesophageal echocardiography, the density was subsequently determined to be cavitation by reviewing the initial images in slow motion.

BackgroundSurgical exclusion of the left atrial appendage (LAA) can be performed at the time of cardiac operation as a potential modality to decrease cardioembolic risk attributable to atrial fibrillation (AF), but it remains unclear if this decreases stroke incidence. Furthermore, it is not known whether LAA exclusion impacts the decision to discontinue anticoagulation impacting subsequent stroke risk.HypothesisLAA exclusion does not significantly alter subsequent anticoagulation use or stroke incidence.MethodsWe studied 124 patients from Olmsted County with prior history of AF who underwent cardiac surgery at our institution between 1993 and 2015. Patients were divided into two groups on the basis of LAA exclusion and matched (1:1) according to 16 pretreatment variables using propensity scores obtained from a logistic regression model. Outcome data collected through chart review for survival, stroke, and the presence and duration of anticoagulation were compared between groups.ResultsThe proportion of patients receiving anticoagulation at discharge and at 5 years was not significantly different between patients who underwent LAA exclusion and those who did not; 90% vs 81%, P = 0.156, 48% vs 49%, P = 0.722, respectively. On Kaplan‐Meier analysis there were no significant differences in time free from stroke between cases and controls. Patients discharged on oral anticoagulation (OAC) had significantly lower risk of stroke (HR = 0.19, 95% confidence interval [CI] = 0.06‐0.59, P = 0.004), independent of whether LAA closure was used.ConclusionLAA exclusion did not appear to reduce early or late stroke. Only OAC was associated with a reduction in stroke risk, underscoring the need for continued anticoagulation in high‐risk patients.

AbstractAimsvon Willebrand factor (VWF) is an independent risk factor for adverse events in patients with non‐valvular atrial fibrillation (NVAF). However, it is unclear if VWF level remains elevated and predictive of stroke during entire course of NVAF.Methods and ResultsIn order to determine if VWF is a time‐dependent blood variable, VWF antigen measured by latex immunoassay in 425 NVAF patients and 100 controls with normal sinus rhythm (NSR) was analyzed according to NVAF duration (<1 month: n = 76, 1‐12 months: n = 98, and >12 months: n = 251). The mean VWF antigen level in NVAF patients with <1‐month duration (167 ± 59%) was not different compared to those with 1‐12 months (157 ± 50%, P = .24) and >12 months duration (156 ± 54%, P = .11) but higher compared to NSR controls (143 ± 48%, P = .003). Higher VWF level correlated with higher CHADS2 scores and with progressing intensity of blood stasis in the left atrium and thrombus formation in all three time periods of atrial fibrillation duration. Patients not treated with warfarin had VWF 30% higher in the first month compared to following months.Conclusionsvon Willebrand Factor is steadily elevated throughout the course of dysrhythmia in NVAF patients treated with warfarin and in those with higher intensity of left atrium blood stasis.

Among patients undergoing cardioversion for atrial fibrillation, the presence of left ventricular thrombus is a relatively uncommon and challenging clinical dilemma. While left atrial appendage thrombus is a contraindication to cardioversion, there is paucity of data regarding the safety of cardioversion in with the presence of left ventricular apical thrombus. Also, thrombus characteristics such as protrusion and mobility on echocardiography are known risk factors for systemic embolism. In this article, we present a case highlighting the management of atrial fibrillation in the setting of left ventricular dysfunction, acute heart failure, and echocardiographic evidence of acute left ventricular apical thrombus.

Background: Prophylactic exclusion of the left atrial appendage (LAA) is often performed during cardiac surgery ostensibly to reduce the risk of stroke. However, the clinical impact of LAA closure in humans remains inconclusive. Methods: Of 10 633 adults who underwent coronary artery bypass grafting and valve surgery between January 2000 and December 2005, 9792 patients with complete baseline characteristics, surgery procedure, and follow-up data were included in this analysis. A propensity score–matching analysis based on 28 pretreatment covariates was performed and 461 matching pairs were derived and analyzed to estimate the association of LAA closure with early postoperative atrial fibrillation (POAF) (atrial fibrillation ≤30 days of surgery), ischemic stroke, and mortality. Results: In the propensity-matched cohort, the overall incidence of POAF was 53.9%. In this group, the rate of early POAF among the patients who underwent LAA closure was 68.6% versus 31.9% for those who did not undergo the procedure ( P <0.001). LAA closure was independently associated with an increased risk of early POAF (adjusted odds ratio, 3.88; 95% confidence interval, 2.89–5.20), but did not significantly influence the risk of stroke (adjusted hazard ratio, 1.07; 95% confidence interval, 0.72–1.58) or mortality (adjusted hazard ratio, 0.92; 95% confidence interval, 0.75–1.13). Conclusions: After adjustment for treatment allocation bias, LAA closure during routine cardiac surgery was significantly associated with an increased risk of early POAF, but it did not influence the risk of stroke or mortality. It remains uncertain whether prophylactic exclusion of the LAA is warranted for stroke prevention during non–atrial fibrillation-related cardiac surgery.