Endothelial Dysfunction in Paroxysmal Atrial Fibrillation as a Prothrombotic State

Abstract

Aim: Atrial fibrillation (AF), regardless of subtype, is associated with a prothrombotic state, which is related to endothelial dysfunction (ED). We hypothesized that paroxysmal atrial fibrillation (PAF) patients have endothelial dysfunction, and this may partially explain the high thromboembolic risk and poorer outcome in this category of patients. Methods: The study population consisted of 100 consecutive outpatients with AF (mean age 65.9 7.9 years; 68 (68%) male) and 21 characteristics and comorbidity matched control subjects (mean age 64.8 7.0 years; 13 (61.9%) male). AF patients were divided into the PAF group (n 50) and permanent/persistent AF (PeAF) group (n 50). Reactive hyperemia pulse amplitude tonometry index (RHI) was measured to evaluate endothelial function. Results: RHI was significantly lower in the PAF (1.67 0.30) and PeAF (1.63 0.28) groups in comparison with control subjects (2.12 0.40, both P 0.001). There was no significant difference in RHI between the PAF and PeAF groups (P 0.88). On linear regression analysis, both PeAF and PAF are significant independent predictors of RHI. Conclusions: In conclusion, ED in PAF patients was comparable to PeAF patients, and the presence of PAF itself is a contributing factor for ED independent of other coexisting comorbidities. This may provide a mechanism explaining why the risk of thromboembolism in PAF is comparable with PeAF patients.J Atheroscler Thromb, 2011; 18:298-304.

Flow-mediated dilation is associated with cardiovascular events in non-valvular atrial fibrillation patients

“…Only few studies demonstrated impaired artery dilatation in AF patients [19,20,29]. FMD was significantly reduced in permanent AF patients compared to healthy subjects, concomitantly with enhanced levels of soluble Eselectin and von Willebrand factor [21], and improved by restoration of sinus rhythm [22] suggesting that implementation of rhythm control may prevent the impairment of FMD and its complication.…”

“…Few studies demonstrated the presence of endothelial dysfunction in AF [19,20]. FMD was significantly impaired in 40 permanent AF patients compared to healthy controls, concomitantly with an enhanced level of soluble E-selectin and von Willebrand factor [21] and was improved by restoration of sinus rhythm [22].…”

Atrial Fibrillation and the Risk of Myocardial Infarction

“…An AF-induced increase in peripheral prothrombotic risk through systemic platelet activation, thrombin generation, and endothelial dysfunction as well as inflammation have been shown in several studies. [36][37][38][39][40][41][42][43][44][45][46][47][48] Coronary thromboembolism with subsequent MI could be another potential explanation for the increased risk of MI in patients with AF. Although the actual incidence of coronary embolism is unknown, it is generally considered rare.…”

Short-term effect of pitavastatin on the reactive hyperemic index in post-menopausal women with high levels in serum LDL-cholesterol

“…The reactive hyperemic index (RHI) is calculated as the ratio of the digital pulse volume during RH divided by that at baseline, using an Endo-PAT 2000 (Itamar Medical Ltd, Israel). Using this test, digital fingertip endothelial function is significantly impaired in postmenopausal women with coronary artery diseases [14] and/or in subjects with atrial fibrillation [15].To determine the short-term effects of pitavastatin on the digital fingertip endothelial function in post-menopausal women with high levels in serum LDL-cholesterol, we examined the effects of the treatment with or without pitavastatin (2 mg/day) for 4 weeks on the RHI using an Endo-PAT 2000 (Itamar Medical Ltd, Israel), serum LDL cholesterol, HDL cholesterol, triglycerides, high sensitive CRP (hs-CRP), and the body mass index (BMI) in non-diabetic Japanese women with LDL cholesterol N 140 mg/dl and RHI b 1.82. The RHI of 1.82 had 81% sensitivity and 80% specificity as an indicator of endothelial dysfunction in Japanese women [14].…”

“…A new method to evaluate endothelial dysfunction called reactive hyperemia peripheral arterial tonometry (RH-PAT) has thus been developed [13][14][15]. Digital pulse amplitude augmentation in response to hyperemia is a novel measure of peripheral vasodilator function that partially depends on endothelium-derived NO [13].…”