Vanessa Roldán

Cessation of oral anticoagulation in relation to mortality and the risk of thrombotic events in patients with atrial fibrillation

Bleeding risk (often perceived, rather than actual) is a common reason for cessation of oral anticoagulation with Vitamin K antagonists (VKA). We investigate clinical outcomes in a consecutive population of VKA naïve atrial fibrillation (AF) patients, who initiated VKA therapy in our clinic. We included consecutive VKA-naïve patients with non valvular AF, initiated on VKA therapy in our anticoagulation outpatient clinic in 2009. During follow-up, adverse events [thrombotic/vascular events (stroke, acute coronary syndrome, acute heart failure and cardiac death), major bleeding and death], and VKA cessation were recorded. At the end of the follow-up, we determined time within therapeutic range (TTR), using a linear approximation (Rosendaal method). We studied 529 patients (49% male, median age 76), median follow-up 835 days (IQR 719-954). During this period 114 patients stopped VKA treatment. 63 patients suffered a thrombotic/cardiovascular event (5.17%/year, 27 thrombotic/ischaemic strokes), 51 major bleeding (4.19%/year) and 48 died (3.94%/year). Median TTR was 54% (34-57). On multivariate analysis (adjusted by CHA₂DS₂-VASc score), VKA cessation was associated with death [Hazard Ratio (HR) 3.43; p<0.001], stroke [4.21; p=0.001] and thrombotic/cardiovascular events [2.72; p<0.001]. Independent risk factors for major bleeding were age [1.08; p<0.001], previous stroke [1.85; p=0.049], and TTR [0.97; p=0.001], but not VKA cessation. In conclusion, in AF patients AF, VKA cessation is independently associated with mortality stroke and cardiovascular events. Specifically, VKA cessation independently increased the risk of stroke, even after adjusting for CHA₂DS₂-VASc score. TTR was an independent risk factor for major bleeding following initiation of VKA therapy.

Interleukin-6, endothelial activation and thrombogenesis in chronic atrial fibrillation

BACKGROUND A prothrombotic or hypercoagulable state has been described in AF, which could increase the risk of thromboembolism. As inflammation has been related to thrombogenesis and endothelial activation, we hypothesised that the prothrombotic state in AF (as assessed by an index of thrombogenesis, prothrombin fragment 1+2 [F1+2]) and endothelial activation (soluble E-selectin (sEsel)) could be related to an index of inflammation (interleukin-6 (IL-6)). PATIENTS AND METHODS We studied 191 consecutive patients (98 male; mean age 72.3+/-9.2 years) with chronic non-rheumatic AF who were not on anticoagulant therapy. Plasma IL-6, sEsel and F1+2 were measured by ELISA. Research indices were compared to 74 controls in sinus rhythm matched for age and sex. In 43 patients with AF, the effects of introducing anticoagulation (INR 2.0-3.0) were also studied. RESULTS Patients with AF had elevated levels of F1+2 (p<0.001) and IL-6 (p=0.045), but not sEsel. There was no significant correlation between F1+2 and IL-6. In multivariate analysis, only F1+2 levels were independently associated with the presence of AF (p=0.001). After oral anticoagulation, plasma levels of F1+2 and sEsel were significantly decreased (both p<0.01). CONCLUSION High levels of IL-6 in AF suggest an inflammatory state, which appears to be more related to clinical variables of the patients, rather than to the presence of AF per se. There was no association of inflammation with endothelial activation (sEsel) or the presence of abnormal thrombogenesis (high F1+2 levels) in AF. Moreover, no changes in IL-6 levels were found despite the reduction of the other markers by oral anticoagulant therapy.

The HAS-BLED Score Has Better Prediction Accuracy for Major Bleeding Than CHADS2 or CHA2DS2-VASc Scores in Anticoagulated Patients With Atrial Fibrillation

OBJECTIVES The aim of this study was to test the hypothesis that a specific bleeding risk score, HAS-BLED (hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile international normalized ratio, elderly, drugs/alcohol concomitantly), was better at predicting major bleeding compared with CHADS2 (congestive heart failure, hypertension, 75 years of age or older, diabetes mellitus, and previous stroke or transient ischemic attack) and CHA2DS2-VASc (congestive heart failure, hypertension, 75 years of age and older, diabetes mellitus, previous stroke or transient ischemic attack, vascular disease, 65 to 74 years of age, female) in anticoagulated atrial fibrillation (AF) patients. BACKGROUND The CHADS2 and CHA2DS2-VASc scores are well-validated stroke risk prediction scores for AF, but are also associated with increased bleeding and mortality. METHODS We recruited 1,370 consecutive AF patients (49% male; median age, 76 years) receiving oral anticoagulation therapy from our outpatient anticoagulation clinic, all of whom were receiving acenocoumarol and had an international normalized ratio between 2.0 and 3.0 during the preceding 6 months. During follow-up, major bleeding events were identified by the 2005 International Society on Thrombosis and Haemostasis criteria. Model performance was evaluated by calculating the C-statistic, and the improvement in predictive accuracy was evaluated by calculating the net reclassification improvement and integrated discrimination improvement. RESULTS After a median follow-up of 996 (range, 802 to 1,254) days, 114 patients (3.0%/year) presented with a major bleeding event; 31 of these events were intracranial hemorrhages (0.8%/year). Based on the C-statistic, HAS-BLED had a model performance superior to that of both CHADS2 and CHA2DS2-VASc (both p < 0.001). Both net reclassification improvement and integrated discrimination improvement analyses also show that HAS-BLED was more accurately associated with major bleeding compared with CHADS2 and CHA2DS2-VASc scores. CONCLUSIONS In anticoagulated AF patients, a validated specific bleeding risk score, HAS-BLED, should be used for assessing major bleeding. The practice of using CHADS2 and CHA2DS2-VASc as a measure of high bleeding risk should be discouraged, given its inferior predictive performance compared with the HAS-BLED score.

Plasma von Willebrand Factor Levels Are an Independent Risk Factor for Adverse Events Including Mortality and Major Bleeding in Anticoagulated Atrial Fibrillation Patients

OBJECTIVES The purpose of this study was to evaluate the prognostic value of plasma von Willebrand factor (vWF) levels and fibrin d-dimer in a large cohort of anticoagulated permanent atrial fibrillation (AF) patients. BACKGROUND In nonanticoagulated AF patients, plasma vWF levels have been related to stroke and vascular events. There are limited data on the prognostic role of biomarkers in anticoagulated AF patients in relation to adverse events (including thromboembolism), mortality, and major bleeding. METHODS We studied 829 patients (50% male; median age 76 years) with permanent AF who were stabilized (for at least 6 months) on oral anticoagulation therapy (international normalized ratio: 2.0 to 3.0). Plasma d-dimer and vWF levels were quantified by enzyme-linked immunosorbent assay. Patients were followed for 2 years, and adverse events (thrombotic and vascular events, mortality, and major bleeding) were recorded. RESULTS Patients were followed for a median of 828 days (range 18 to 1,085 days). On multivariate analysis, age 75 years and older, previous stroke, heart failure, and high plasma vWF levels (≥ 221 IU/dl) were associated with future adverse cardiovascular events (all p values <0.05). High plasma vWF levels, elderly patients, diabetes, hypercholesterolemia, and current smoking were associated with mortality (all p values <0.05). High plasma vWF levels were also an independent predictor of major bleeding (hazard ratio: 4.47, 95% confidence interval: 1.86 to 10.75; p < 0.001). High plasma vWF levels were able to refine clinical risk stratification schema for stroke (CHADS₂ [Congestive heart failure, Hypertension, Age ≥ 75, Diabetes mellitus, and prior Stroke or transient ischemic attack (doubled)], CHA₂DS₂-VASc [Congestive heart failure, Hypertension, Age ≥ 75 years, Diabetes mellitus, Stroke, Vascular disease, Age 65 to 74 years, Sex category]) and bleeding (HAS-BLED [Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile International Normalized Ratio, Elderly, Drugs/alcohol concomitantly]). d-dimer did not show any significant impact on adverse events. CONCLUSIONS High plasma vWF levels (≥221 IU/dl) are an independent risk factor for adverse events in anticoagulated permanent AF patients. This biomarker may potentially be used to refine stroke and bleeding clinical risk stratification in AF.

Relation of the HAS-BLED bleeding risk score to major bleeding, cardiovascular events, and mortality in anticoagulated patients with atrial fibrillation.

Background— Stroke risk in atrial fibrillation (AF) using oral vitamin K antagonists is closely related to bleeding risk. The HAS-BLED (hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile INR [international normalized ratio], elderly, drugs/alcohol concomitantly) bleeding score has demonstrated usefulness in assessing major bleeding risk in patients with AF. However, risk factors for warfarin-associated bleeding also predict stroke risk in patients with AF. We tested the usefulness of the HAS-BLED score for predicting both major bleeding and cardiovascular events in a cohort of anticoagulated patients with AF. Methods and Results— We recruited 965 consecutive anticoagulated outpatients with permanent or paroxysmal AF who were stabilized for at least 6 months on oral anticoagulation (international normalized ratio, 2.0–3.0). Medical history and HAS-BLED score were assessed. Cox regression models were used to determine the association between clinical risk factors and bleeding episodes, adverse cardiovascular events, and mortality. The median HAS-BLED score was 2 (range, 0–6; 29% with a score ≥3 [ie, high risk]). Median follow-up was 861 days (range, 718–1016 days). Independent predictors for major bleeding were age ≥75 years (hazard ratio [HR], 1.74; 95% CI, 1.05–2.87; P=0.030), male sex (HR, 1.70; 95% CI, 1.03–2.80; P=0.036), renal impairment (HR, 2.12; 95% CI, 1.20–3.73; P=0.010), previous bleeding episode (HR, 6.00; 95% CI, 3.73–9.67; P<0.001), current alcohol consumption (HR, 2.28; 95% CI, 1.03–5.06; P=0.043), and concomitant malignant disease (HR, 2.17; 95% CI, 1.13–4.18; P=0.020). Independent predictors for adverse cardiovascular events were age >75 years (HR, 2.20; 95% CI, 1.40–3.46; P=0.001), heart failure (HR, 1.78; 95% CI, 1.20–2.86; P=0.001), and previous stroke (HR, 1.85; 95% CI, 1.20–2.86; P<0.001). The HAS-BLED score was highly predictive for major bleeding events (HR, 2.04; 95% CI, 1.68–2.49; P<0.001) and adverse cardiovascular events (HR, 1.51; 95% CI, 1.27–1.81; P<0.001). The incidence of both bleeding and adverse cardiovascular events was higher as HAS-BLED score increased, and crude bleeding rates only exceeded thrombotic events at a HAS-BLED score >3. The HAS-BLED score also predicted all-cause mortality (HR, 1.68; 95% CI, 1.40–2.01; P<0.001). Conclusions— The HAS-BLED score not only is useful in the assessment of bleeding risk, but also shows some predictive value for cardiovascular events and mortality in anticoagulated patients with AF, consistent with the relationship between thrombosis and bleeding. Nonetheless, the HAS-BLED score has been designed for predicting bleeding risk rather than thrombotic events per se, and specific risk scores for cardiovascular events and mortality should be applied for these events.

Is Thrombogenesis in Atrial Fibrillation Related to Matrix Metalloproteinase-1 and Its Inhibitor, TIMP-1?

Background and Purpose— Decreased matrix metalloproteinase-1 (MMP-1) and increased levels of its inhibitor, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), reflect impaired matrix degradation with an increase in fibrosis. A prothrombotic state has been described in atrial fibrillation (AF), increasing the risk of stroke and thromboembolism. Because structural abnormalities and remodeling of atria have been observed in AF, we hypothesized that the prothrombotic state in AF may be related to abnormal indexes of matrix degradation. Methods— We studied 48 consecutive patients (30 men; age, 70.5±9.0 years) with chronic nonrheumatic AF who were not on anticoagulation. Plasma levels of MMP-1, TIMP-1, and prothrombin fragment 1+2 (F1+2, an index of thrombogenesis) were measured by enzyme-linked immunosorbent assay. M-mode, 2-dimensional, and Doppler echocardiographic studies were performed in all patients. Research indexes were compared with data from 32 control subjects in sinus rhythm who were of similar age and sex. Results— Patients with AF had lower levels of MMP-1 (P =0.011) but increased levels of TIMP-1 (P =0.033) and F1+2 (P <0.001) and a higher ratio of TIMP-1 to MMP-1 (P =0.009) compared with control subjects. After adjustment for sex, age, hypertension, and diabetes, TIMP-1 levels and the ratio of TIMP-1 to MMP-1 correlated with F1+2 levels (r =0.24, P =0.038; and r =0.26, P =0.023, respectively). In multivariate analysis, there was no independent relationship between MMP-1, TIMP-1, or ratio of TIMP-1 to MMP-1 and the presence of AF. Conclusions— Patients with AF have evidence of impaired matrix degradation, but this was not independently associated with the presence of AF on multivariate analysis. However, an independent relationship was found between the MMP/TIMP system and prothrombotic state (assessed by F1+2 levels).

Antithrombotic management in patients undergoing electrophysiological procedures: a European Heart Rhythm Association (EHRA) position document endorsed by the ESC Working Group Thrombosis, Heart Rhythm Society (HRS), and Asia Pacific Heart Rhythm Society (APHRS).

Since the advent of the non-vitamin K antagonist oral anticoagulant (NOAC) agents, which act as direct thrombin inhibitors or inhibitors of Factor Xa, clinicians are provided with valuable alternatives to vitamin K antagonists (VKAs). At the same time, electrophysiologists frequently perform more invasive procedures, increasingly involving the left chambers of the heart. Thus, they are constantly faced with the dilemma of balancing the risk for thromboembolic events and bleeding complications. These changes in the rapidly evolving field mandate an update of the European Heart Rhythm Association (EHRA) 2008 consensus document on this topic.1 The present document covers the antithrombotic management during different ablation procedures, implantation or exchange of cardiac implantable electronical devices (CIEDs), as well as the management of peri-interventional bleeding complications. The document is not a formal guideline and due to the lack of prospective randomized controlled trials (RCTs) for many of the clinical situations encountered, the recommendations are often ‘expert opinion’. The document strives to be practical for which reason we subdivided it in the three main topics: ablation procedure, CIED implantation or generator change, and issues of peri-interventional bleeding complications on concurrent antiplatelet therapy. For quick reference, every subchapter is followed by a short section on consensus recommendations. Many RCTs are ongoing in this field and it is hoped that this document will help to prompt further well-designed studies. ### Ablation of atrial fibrillation, left atrial arrhythmias and right sided atrial flutter In patients with symptomatic paroxysmal or even persistent atrial fibrillation (AF), catheter ablation is indicated when antiarrhythmic drugs have failed in controlling recurrences or even as a first-line therapy in selected patients.2–4 Patients with AF have an increased risk of thromboembolic events, which varies according to the presence of several risk factors.5,6 Apart from their intrinsic thromboembolic risks, ablation in these patients increases thromboembolic risk due to the introduction and manipulation …

Does chronic kidney disease improve the predictive value of the CHADS2 and CHA2DS2-VASc stroke stratification risk scores for atrial fibrillation?

Chronic Kidney Disease (CKD) constitutes an adverse risk factor in chronic anticoagulated atrial fibrillation (AF) patients, being related to adverse cardiovascular events, mortality and major bleeds. It is unclear if CKD adds independent prognostic information to stroke risk stratification schemes, as the risk factor components of the CHADS2 and CHA2DS2-VASc scores are themselves related to renal dysfunction. The aim of our study was to determine if CKD independently improves the predictive value of the CHADS2 and CHA2DS2-VASc stroke stratification scores in AF. We recruited consecutive patients (n=978) patients (49% male; median age 76) with permanent or paroxysmal AF on oral anticoagulants with acenocoumarol, from our out-patient anticoagulation clinic. After a median follow-up of 875 (IQR 706-1059) days, we recorded stroke/transient ischaemic attack (TIA), peripheral embolism, vascular events (acute coronary syndrome, acute heart failure and cardiac death) and all-cause mortality. During follow-up, 113 patients (4.82%/year) experienced an adverse cardiovascular event, of which 39 (1.66%/year) were strokes, 43 (1.83%/year) had an acute coronary syndrome and 32 (1.37%/year) had acute heart failure. Also, 102 patients (4.35%/year) died during the following up, 31 of them (1.32%/year) as a result of a thrombotic event. Based on c-statistics and the integrated discrimination improvement (IDI), CKD did not improve the prediction for stroke/systemic embolism, thrombotic events and all-cause mortality using the CHADS2 and CHA2DS2-VASc scores. In conclusion, evaluating renal function in AF patients is important as CKD would confer a poor overall prognosis in terms of thromboembolic events and all-cause mortality. Adding CKD to the CHADS2 and CHA2DS2-VASc stroke risk scores did not independently add predictive information.

Renal Impairment in a “Real-Life” Cohort of Anticoagulated Patients With Atrial Fibrillation (Implications for Thromboembolism and Bleeding)

Renal dysfunction is highly prevalent among patients with atrial fibrillation (AF) and confers an increased risk of thrombotic and bleeding complications. We evaluated the effect of renal function on prognosis in anticoagulated patients with AF and assessed the changes in renal function during a long-term follow-up period. We recruited 978 consecutive stable anticoagulated patients with AF from our outpatient anticoagulation clinic (international normalized ratio 2.0 to 3.0 within the previous 6 months). The estimated glomerular filtration rate (eGFR) was calculated using the Modification of Diet in Renal Disease equation at inclusion and 2 years of follow-up. Adverse events were recorded during follow-up (thrombotic/vascular events, major bleeding episodes, and mortality). Longitudinal changes in renal function were analyzed in 886 patients (90.6%). At baseline, the median eGFR using the Modification of Diet in Renal Disease equation was 70.24 ml/min/1.73 m(2) (interquartile range 46.79 to 72.52). During follow-up, a low eGFR was associated with thrombotic/vascular events, with every 30 ml/min/1.73 m(2) eGFR decrease (hazard ratio 1.42, 95% confidence interval [CI] 1.11 to 1.83, p = 0.006), bleeding (hazard ratio 1.44, 95% CI 1.08 to 1.94, p = 0.015), and mortality (hazard ratio 1.47, 95% CI 1.13 to 1.91, p = 0.004). After excluding patients with a baseline eGFR <30 ml/min/1.73 m(2), the mean eGFR in our cohort decreased >10 ml/min/1.73 m(2) in 181 patients (21%) during the follow-up period. The variables associated with severe renal impairment during follow-up were heart failure (odds ratio 3.58, 95% CI 1.36 to 9.42, p = 0.010), basal eGFR (odds ratio 6.34, 95% CI 2.44 to 16.50, p <0.001), and CHADS2 (Congestive heart failure, Hypertension, Age >75 years, Diabetes mellitus, and previous Stroke or transient ischemic attack [doubled]) score (odds ratio 1.63, 95% CI 1.19 to 2.23, p = 0.003). In conclusion, the presence of impaired renal function was closely related to thrombotic/vascular events, bleeding, and mortality in anticoagulated patients with AF. During follow-up, 1/5 of the patients had significant impairment in renal function. Importantly, normal or mild renal dysfunction at baseline did not exclude the subsequent development of severe renal dysfunction during the follow-up period.

Pharmacogenetic relevance of CYP4F2 V433M polymorphism on acenocoumarol therapy

VKORC1 and CYP2C9 polymorphisms are used to predict the safe dose of oral anticoagulant therapy. A new variant of CYP4F2 (V433M) has recently been related to the required warfarin dose. We evaluated its influence in earliest response to acenocoumarol in 100 selected men who started anticoagulation (3 mg for 3 consecutive days). V433M genotype exerted a gene dosage-dependent effect on the decrease of factors II, VII, IX, and X in the earliest response to acenocoumarol, with homozygous 433V subjects being the most sensitive. Similarly, after the initiation of therapy, international normalized ratio also experienced a gene dosage-dependent effect (P = .015), and 433V subjects needed 4 mg/week less than 433M carriers to achieve a steady anticoagulation (P = .043). Multivariate linear regression analysis revealed a significant contribution of V433M polymorphism to variability of both early international normalized ratio value (R(2) = 0.14) and dose requirements (R(2) = 0.19). Our data underline the relevant role of CYP4F2 V433M polymorphism in the pharmacogenetics of coumarin anticoagulants.