L. Fauchier (1), S. Taillandier (1), I. Lagrenade (1), C. Pellegrin (1), L. Gorin (1), A. Bernard (1), B. Rauzy (1), D. Babuty (1), GYL.

Transcription

1 Prognosis in patients with atrial fibrillation and CHA 2 DS 2 VASc score=0 in a real world community based cohort study: Loire Valley Atrial Fibrillation project L. Fauchier (1), S. Taillandier (1), I. Lagrenade (1), C. Pellegrin (1), L. Gorin (1), A. Bernard (1), B. Rauzy (1), D. Babuty (1), GYL. Lip (2) (1) Services de Cardiologie, Centre Hospitalier Universitaire Trousseau, Tours, France (2) City Hospital, Centre for Cardiovascular Sciences, Birmingham, United Kingdom

2 NO CONFLICT OF INTEREST TO DECLARE

3 Background Based on 2010 ESC guidelines, thromboprophylaxis for patients with atrial fibrillation (AF) without any risk factor (CHA 2 DS 2 -VASc score=0) may be aspirin or no antithrombotic therapy, Oral anticoagulation is the preferred therapy in all other patients with 1 risk factors.

4 CHA 2 DS 2 VASc (non valvular AF) AF - ESC Guidelines, EHJ 2010

5 Objectives The aims of our study were : To survey the prevalence of AF patients with a CHA 2 DS 2 -VASc score=0 in a real world community cohort study, To determine the rate of events in these AF patients during follow up. To evaluate the impact of antithrombotic management on prognosis in this setting

6 Methods - Data collection All patients with AF between 2000 and 2010 seen in the cardiology department in our public institution (academic hospital, 4 hospitals, all specialties, 3ary referral center) identified and followed until December Identification by search in the hospital discharge records. Computerized codification system filled in for each patient using the International Classification of Diseases (ICD-10) of the WHO Information on type of AF, 1ary diagnoses and coexisting conditions, performed procedures, medication at discharge and in-hospital events.

7 CHA 2 DS 2 VASc schema (non-valvular AF) Lip GYH et al, Chest AF - ESC Guidelines, EHJ 2010

8 Patient characteristics Among 8962 patients with AF, 616 (7%) had a CHA 2 DS 2 -VASc score = 0. Age 47±13 years 126 with permanent AF 490 with non permanent AF Oral anticoagulant prescribed in 273 patients (44%) Antiplatelet therapy alone in 145 patients (24%) No antithrombotic treatment in 198 patients (32%).

9

10 Baseline characteristics of patients with AF and a CHA2DS2VASc score = 0. Patients All (n=616) Treated with oral anticoagulant (n=273) Treated with antiplatelet agent (n=145) No antithrombotic treatment (n=198) P Age (years) (mean SD) < Smoking history 56 (9%) 26 (10%) 15 (10%) 15 (8%) 0.65 Dyslipidemia 40 (6%) 23 (8%) 9 (6%) 8 (4%) 0.23 Renal insufficiency 2 (0%) 0 (0%) 0 (0%) 2 (1%) 0.13 Pacemaker or ICD 38 (6%) 21 (8%) 6 (4%) 11 (6%) 0.28 Alcohol abuse 22 (4%) 10 (4%) 3 (2%) 9 (5%) 0.46 Thyroid disorder 14 (2%) 9 (3%) 2 (1%) 3 (2%) 0.29 AF pattern Paroxysmal AF 454 (74%) 159 (58%) 130 (90%) 165 (83%) < among Persistent AF 36 (6%) 24 (9%) 4 (3%) 8 (4%) the 3 groups Permanent AF 126 (20%) 90 (33%) 11 (7%) 25 (13%) for AF pattern HASBLED score Medication Class I AAA 321 (52%) 139 (51%) 97 (67%) 85 (43%) 0.12 Class III AAA 82 (13%) 49 (18%) 17 (12%) 16 (8%) ACE inhibitor or ARB 36 (6%) 16 (6%) 12 (8%) 8 (4%) 0.47 Digoxin 131 (21%) 60 (22%) 41 (28%) 30 (15%) 0.27 Diuretic 30 (5%) 16 (6%) 10 (7%) 4 (2%) 0.47 Beta blocker 249 (40%) 117 (43%) 67 (46%) 65 (33%) 0.37 Calcium channel blocker 29 (5%) 11 (4%) 10 (7%) 8 (4%) 0.68 Aspirin 142 (23%) 5 (2%) 136 (94%) 0 (0%) < Clopidogrel 9 (1%) 2 (1%) 7 (5%) 0 (0%) 0.06

11 Antithrombotic treatment in patients with a CHA2DS2VASc score = 0 according to the type of AF.

12

13 Stroke/thromboembolic events in AF and a CHA2DS2VASc score = 0 in relation to AF pattern and antithrombotic treatment

14 CHA 2 DS 2 VASc Validation in a nationwide cohort study All patients with AF in Denmark, no VKA, period n=73,538 prevalence,% 8% 12% 80% C statistics at 10 years follow-up : CHADS 2 = 0.81 CHA 2 DS 2 -VASc = 0.89 Olesen, Lip, Hansen et al, BMJ 2011

15 FU: mortality, stroke/thromboembolism and bleeding Follow-up : median=244 days, interquartile range= days 10 strokes or systemic thromboembolism 5 ischemic strokes, 4 haemorrhagic strokes, 1 systemic embolism Stroke/TE event rate = 0.67 % / year (0.64% / year in untreated patients) None of these patients had a change in antithrombotic ttt during FU 17 deaths 5 cardiovascular deaths (1 in a pat. with Duchenne MD who developed HF, 1 sudden death with suspicion of Brugada syndrome, 1 hemorrhagic stroke, 1 PE, 1 acute respiratory distress in a pat. who developed CAD) 12 non-cardiovascular deaths (10 cancers, 2 sepsis) Death rate = 1.14% / year (1.05% / year in untreated patients) 19 bleeding complications Rate of bleeding events = 1.05% / year in untreated patients

16

17

18 Hazard ratio of events during FU in AF with a CHA2DS2-VASc score = 0 Anticoagulation vs no anticoagulation Hazard Ratio (95% Confidence Interval) p Antiplatelet agent vs no antiplatelet agent Hazard Ratio (95% Confidence Interval) p Anticoagulation or antiplatelet agent vs no antithrombotic therapy Hazard Ratio (95% Confidence Interval) p All Deaths (n=17) 0.78 ( ) ( ) ( ) 0.87 Non cardiovascular death (n=12) 0.80 ( ) ( ) ( ) 0.87 Stroke (ischemic or hemorrhagic) (n=9) Stroke or systemic thromboembolism (n=10) 0.91 ( ) ( ) ( ) ( ) ( ) ( ) 0.84 Bleeding events (n=19) 1.22 ( ) ( ) ( ) 0.75 Net clinical benefit (n=34) 0.98 ( ) ( ) ( ) 0.53

19 Study limitations It was not a randomized trial but an observational real life study. All data was obtained retrospectively from a search in hospital discharge records with limitations of diagnostic coding and case ascertainment. We did not have access to data on some events occurring outside our area and out-of-hospital. Antithrombotic treatment was determined at baseline, and we were not able to adjust for all possible changes in treatment status during FU.

20 Conclusion In this real life cohort study, patients with CHA 2 DS 2 VASc score = 0 (7% of all patients with AF) had a low risk of stroke or systemic embolism (yearly rate 0.67%) without differences in patients who received an oral anticoagulant, an antiplatelet agent, or no antithrombotic treatment. Antithrombotic treatment in patients with AF and a CHA 2 DS 2 VASc score = 0 is not significantly associated with any clinical benefit. This supports current guideline recommendations for no antithrombotic therapy in these truly low risk patients.

21

22 Statistical analysis Observed survival was estimated using the Kaplan- Meier method. To identify independent characteristics associated with events during FU, a logistic regression model was used with adjustment on potential confounders. The association of antithrombotic at discharge with events during FU was also developed using a Cox proportional hazards model.