Mean CHADS2 Research Articles

CHADS2 SCORE PREDICTS THE OCCURRENCE OF DEATH, STROKE AND HEART FAILURE IN PATIENTS WITH ATRIAL FIBRILLATION: A SINGLE-CENTER COHORT STUDY

Methods: 541 patients with an ECG-documented AF were consecutively included in our Department and followed-up for a mean of 1.76 ± 1.43 years. Results: Mean CHADS2 risk score was 1.69 ± 1.30: 116 (21.4%) patients had a score 0, 136 (25.2%) a score 1 and 289 (53.4%) a score ≥ 2. HF occurs at follow-up with different figures according to the CHADS2 risk score: 3 (2.6%) for score 0, 11 (8.1%) for score 1 and 62 (21.5%) for a score ≥ 2. Treatment at discharge included warfarin in 366 patients (67.7%), aspirin in 170 (32.3%). At follow-up, 97 patients (17.9%) died, 22 (4.1%) had stroke and 76 (14.1%) had at least one episode of HF. Based on unadjusted Kaplan-Meier plots, representing patients with a score of 0, 1 and ≥ 2 , those with a CHADS2 = 2 had the worst prognosis (figure, Lograng, p<0.001). The multivariate analysis showed that the following clinical parameters were significant predictors of the occurrence of the composite endpoint: permanent AF (OR 2.07, p=0.0004), age (OR 1.03, p=0.0032), warfarin at discharge (OR 0.59, p=0.0455) and antiplatelet agents at discharge (OR 0.56, p=0.0366). Conclusion: Our study suggests the ability of CHADS2 scoring system for thromboembolism to identify AF patients at high-risk of cardiovascular events including heart failure. However, refinements are mandatory to implement this widely used clinical approach.

Atrial fibrillation in Africa: clinical characteristics, prognosis, and adherence to guidelines in Cameroon

The purpose of this prospective study was to characterize the clinical profile of patients with atrial fibrillation (AF) in the urban population of a sub-Saharan African country and to assess how successfully current guidelines are applied in that context. This prospective study involved 10 cardiologists in Cameroon. Enrolment started on 1 June 2006 and ended on 30 June 2007. Consecutive patients were included if they were >18 years and AF was documented on an ECG during the index office visit. In this survey, 172 patients were enrolled (75 males and 97 females; mean age 65.8 +/- 13 years). The prevalence of paroxysmal, persistent, and permanent AF was 22.7, 21.5, and 55.8%, respectively. Underlying cardiac disorders, present in 156/172 patients (90.7%), included hypertensive heart disease (47.7%), valvular heart disease (25.6%), dilated cardiomyopathy (15.7%), and coronary artery disease (6%). A rate-control strategy was chosen in 83.7% of patients (144 of 172) and drugs most commonly used were digoxin and amiodarone. The mean CHADS(2) score was 1.9 +/- 1.1 and 158 of 172 patients (91.9%) had a CHADS(2) score > or =1. Among patients with an indication for oral anticoagulation (OAC), only 34.2% (54 of 158) actually received it. During a follow-up of 318 +/- 124 days, 26 of 88 patients died (29.5%), essentially from a cardiovascular cause (15 of 26). Ten patients (16.1%) had a non-lethal embolic stroke and 23 (26.1%) had symptoms of severe congestive heart failure. Clinical presentation of AF in Cameroon is much more severe than in developed countries. A rate-control strategy is predominant in Cameroon and OAC is prescribed in only 34.2% of eligible patients, despite a high CHADS(2) score at inclusion. Death and stroke rate at 1 year are very high in Cameroon possibly because of a lower use of OAC, and a higher prevalence of rheumatic mitral disease and of more severe co-morbidities.

Percutaneous closure of left atrial appendage to prevent embolic events in high‐risk patients with chronic atrial fibrillation

Percutaneous closure of the left atrial appendage (LAA) is a novel alternative for the treatment of patients with atrial fibrillation (AF) and with a high risk of stroke who are not eligible for long-term anticoagulation therapy. The aim of this study was to asses the safety, feasibility, and long-term efficacy of this procedure. From July 2004 to June 2007, 20 patients (13 male, mean age 69 +/- 8 years) with non-valvular AF (NV-AF) underwent LAA percutaneous closure using the PLAATO system, implanted through a transeptal access. All patients had contraindications to anticoagulant therapy and were at high risk for cardioembolic stroke (mean CHADS(2) score 3 +/- 1.2). A trans-thoracic echocardiogram was performed at 1, 3, and every 6 months after the procedure, whereas a trans-oesophageal echocardiogram (TOE) was scheduled at 6 months. After 24 months, a phone interview was obtained. All procedures were successfully performed in 18 patients. In two patients, LAA closure was not feasible for the presence of a multilobed LAA. Two patients underwent percutaneous closure of patent foramen ovale in the same session. In one patient, the procedure was complicated by cardiac perforation with pericardial effusion, treated with pericardiocentesis. At a mean follow up of 40 +/- 10 months, no embolic events occurred. One patient died, after 36 months, for gastric cancer. TOE examination showed the complete exclusion of the LAA in all patients. Percutaneous closure of LAA is safe and efficacious to prevent stroke in patients with NV-AF at high risk for cardioembolic events, with contraindications to anticoagulant therapy.

Atrial fibrillation management by practice cardiologists: a prospective survey on the adherence to guidelines in the real world

The purpose of this prospective study was to characterize the clinical profile of patients with atrial fibrillation (AF) in cardiology practice and to assess how successfully guidelines have been implemented in real-world practice. This prospective study involved 23 cardiologists established in office practice in Geneva. Enrollment started on 1 January 2005 and ended on 31 December 2005. Consecutive patients were included if they were >18 years and had AF documented on an ECG during the index office visit or during the preceding month. In this survey, 622 ambulatory patients were enrolled (390 males and 232 females; mean age 69.8 +/- 11.8 years). The prevalence of paroxysmal, persistent, and permanent AF was 35, 18, and 47%, respectively. Underlying cardiac disorders present in 513 patients (82%) included hypertensive heart disease (30%), valvular heart disease (27%), coronary artery disease (18%), and myocardial disease (11%). A rate-control strategy was chosen in 53% of the patients (331/622). The mean CHADS(2) score was 1.43 +/- 1.24, and 458/622 patients (73.6%) had a CHADS(2) score >or=1. Among patients with an indication to oral anticoagulant therapy (OAT), 88% (403/458) effectively received it. The rate of OAT was closely correlated with an increasing CHADS(2) score, particularly with patients age (72, 81, and 87% for patients <65, 65-75, and >75 years of age, respectively). True contraindication for OAT was present in 4% (18/458). In the low-risk group (CHADS(2) score = 0), 58% were prescribed OAT, but in 37% of them only for a short period of time (cardioversion/ablation). After a follow-up of 396 +/- 109 days, 72% of the study group (410/570) was still treated by OAT. During follow-up, 23/570 patients died (4%), essentially from a cardiovascular cause (15/23), 15 had a non-lethal embolic stroke (2.7%), and 8 had significant bleeding complications (1.5%). This study shows one of the highest OAT prescription rates for AF reported until now and demonstrates how successfully guidelines can be applied in the real world. A definite overinterpretation of current guidelines is observed in low-risk patients with AF. True contraindication for OAT (4%) and significant bleeding during OAT (1.5%) were rare.

Clinical and echocardiographic measures governing thromboembolism destination in atrial fibrillation

Although infrequent, embolic occlusion to non-cerebral arteries may result in limb loss, organ failure, and death. The aim of this study was to define clinical and echocardiographic characteristics determining thromboembolism destination in non-valvular atrial fibrillation. An inception cohort of individuals (n=72) were identified with incident peripheral embolism in the setting of non-valvular atrial fibrillation (1995-2005). A randomly selected group of atrial fibrillation related stroke patients (n=100) were identified for comparison. Arteries of the extremities were the most common site of embolism (85%); lower extremity involvement was twice as common compared with the upper extremity. Clinical features distinguishing peripheral embolism from stroke included age>75, heart failure and hypertension. Severe left ventricular dysfunction, spontaneous echo contrast and left atrial thrombus were 2-3 fold more common in peripheral embolism patients. Mean CHADS-2 scores were low and comparable for both groups. By multivariate analysis, age>5 years (hazard ratio [HR] 2.3, 95% confidence interval [CI] 1.3-3.9; p=0.05) was predictive of peripheral embolism. After adjustment for age>75 years, severe left atrial enlargement (HR 1.8, 95% CI 0.99-3.1; p=0.055) and CHADS score (HR 1.2, 95% CI 0.99-1.6; p=0.06) were of borderline significance. In conclusion, several clinical and echocardiographic measures distinguish the clinical presentation of thromboembolism in non-valvular atrial fibrillation. Small emboli are destined to lodge in the cerebral circulation as a result of hydrodynamic, anatomic, and physical factors. Advanced age, atrial enlargement and other co-morbidities may increase the propensity for the formation of larger thrombi which may bypass the carotid orifice merely as a function of size.

The Hyperventilation Syndrome

The direct factor-Xa inhibitor apixaban is approved e.g. for the prevention of stroke in patients with atrial fibrillation (AF). Although routine monitoring of apixaban therapy is currently not recommended, selective monitoring could be useful to optimize efficacy and safety in certain clinical situations. We studied the exposure and effect of apixaban using different laboratory methods in a clinical setting with a well-defined cohort of AF patients.Seventy AF patients (72 ± 7.4 years, 64 % men, mean CHADS2 score 1.7) treated with apixaban 2.5 (n = 10) or 5 mg BID (n = 60). Trough plasma apixaban concentrations determined by liquid chromatography-tandem mass-spectrometry (LC-MS/MS) were compared to the coagulation assays Anti-factor Xa, PT-INR and aPTT.The apixaban plasma concentration determined by LC-MS/MS varied more than 10-fold overall. The range was between 15-83 and 29-186 ng/mL for the 2.5 mg BID and 5 mg BID respectively, with patients receiving 5 mg BID having significantly higher apixaban concentrations (p < 0.001). A strong correlation between LC-MS/MS and anti-FXa-assay was found (p < 0.001), while aPTT and PT-INR were not sensitive enough. There were no significant correlations between gender, creatinine clearance, body weight or age and apixaban exposure.Anti-FXa-assay performed well upon apixaban concentrations in a normal exposure range. Still LC-MS/MS remains the “gold standard” method, covering also low concentrations. Compared to clinical trials, we observed relatively lower apixaban exposure and a more pronounced difference between high and low dose. Additional information regarding apixaban exposure and benefit-risk profile is needed in order to individualize treatment.