MWNAF trial

Exclusion criteria comprised the following: (1) inability to obtain informed consent; (2) uncontrolled systolic hypertension (>180 mm Hg); (3) chronic renal failure (serum creatinine >3 mg/dl); (4) chronic liver failure (basal International Normalized Ratio [INR] >1.5); (5) chronic alcoholism or a psychiatric disorder; (6) major bleeding in the preceding 6 months; (7)heart failure (New York Heart Association classes III to IV); (8) if the patient was receiving antiplatelet therapy > or =1 week before; (9) life expectancy of <12 months; (10) planned cardioversion; (11) previous cerebral ischemia; (12) recent (<1 month) myocardial infarction; and (13) treatment with barbiturate or carbamazepine. Moreover, patients were excluded if they had mitral stenosis, moderate or severe mitral incompetence, dilated cardiomyopathy, or intracardiac thrombus.

Baseline characteristics

age(mean)	74.14
male(%)	45.04
hypertension(%)	60.03
diabete mellitus(%)	13.01

Method and design

Randomized effectives	150 / 153 (studied vs. control)
Design	Parallel groups
Blinding	Open
Follow-up duration	14.5 months
Lost to follow-up	0.9%
Number of centre	nr but multicentric
Geographic area	Italy
Hypothesis	non inferiority
Primary endpoint	thromboembolic event,cerebral or fatal bleeding and vascular death
Remarks	Withdrawal from study treatment is reported here only unrelated to primary or secondary endpoints.
Withdrawals (T1/T0)	16% / 15%

Results

Endpoint Studied treat.
n/N Control treat.
n/N Graph RR [95% CI]

Cardiovascular death

5 / 150
3 / 153
classic 1,70 [0,41;6,99]

thrombo-embolic event (cerebral or systemic)

5 / 150
0 / 153
classic 21,42 [0,39;1�176,44]

TE event or ischemic stroke or systemic embolism

5 / 150
0 / 153
classic 21,42 [0,39;1�176,44]

ischemic stroke

5 / 150
0 / 153
classic 21,42 [0,39;1�176,44]

MI (fatal and non fatal)

1 / 150
0 / 153
classic 5,10 [0,07;371,47]

Haemmorhagic stroke

0 / 150
1 / 153
classic 0,20 [0,00;14,86]

Major bleeding

1 / 150
4 / 153
classic 0,26 [0,03;2,26] 0 2 1.0

Endpoint	Events (%)		Relative Risk	95% CI	Endpoint definition in the trial	Ref
Relative risks
Endpoint	Studied treat.	Control treat.	Relative Risk	95% CI	Endpoint definition in the trial	Ref
Cardiovascular death	5 / 150 (3,3%)	3 / 153 (2,0%)	1,70	[0,41;6,99]	death in which a non vacsular cause was not clearly documented
thrombo-embolic event (cerebral or systemic)	5 / 150 (3,3%)	0 / 153 (0,3%)	10,20	[0,56;185,08]
TE event or ischemic stroke or systemic embolism	5 / 150 (3,3%)	0 / 153 (0,3%)	10,20	[0,56;185,08]	thrombo-embolic event, ischemic stroke or systemic embolism
ischemic stroke	5 / 150 (3,3%)	0 / 153 (0,3%)	10,20	[0,56;185,08]	sudden neurologic deficit lasting more than 24 hours in the absence of cerebral hemorrhage at neuroimaging
MI (fatal and non fatal)	1 / 150 (0,7%)	0 / 153 (0,3%)	2,04	[0,07;60,36]	typical chest pain,ECG changes,significant increase in cardiac enzymes
Haemmorhagic stroke	0 / 150 (0,3%)	1 / 153 (0,7%)	0,51	[0,02;15,09]	documented at neuroimaging
Major bleeding	1 / 150 (0,7%)	4 / 153 (2,6%)	0,26	[0,03;2,26]	fatal ;intracranial ,ocular,articular or retroperitoneal; requiring surgery or angiographic intervention; Hb reduction of 2 g/dL and/or need for transfusion of 2 blood units
The primary endpoint (if exists) appears in blod characters
Reference(s) used for data extraction:

Endpoint	Events rate		Absolute risk reduction (ARR)
Absolute risk reduction
Endpoint	Studied treat.	Control treat.	Absolute risk reduction (ARR)
Cardiovascular death	3,33%	1,96%	1,4%
Major bleeding	6,67‰	2,61%	-19,5‰

Meta-analysis of all similar trials:

antithrombotics in atrial fibrillation for primary prevention of thromboembolic events

Reference(s)

Trials register #

Pengo V, Zasso A, Barbero F, Banzato A, Nante G, Parissenti L, John N, Noventa F, Dalla Volta S. Effectiveness of fixed minidose warfarin in the prevention of thromboembolism and vascular death in nonrheumatic atrial fibrillation.. Am J Cardiol 1998 Aug 15;82:433-7
Pubmed | Hubmed | Fulltext

MWNAF study, 1998

Treatments

Patients

Method and design

Results

Reference(s)