Stroke prophylaxis in high-risk patients with atrial fibrillation: rhythm vs. rate control strategy

"Rhythm" and "Rate" control strategies require partially different organization, and a different involvement of Specialists and General Practitioners; we verified whether the strategy assignment modified the approach to stroke prophylaxis.

Survey in general practice: 233 GPs identified all patients with codified atrial fibrillation (AF) diagnosis, checked the diagnosis (ECG/hospital discharge document), and filled a structured questionnaire on stroke risk-factors, prophylactic therapy, and reasons for warfarin non prescription in CHADS ≥2 patients. Data were collected as an "aggregate."

Population observed: 295,906 patients aged >14; 6,036 with confirmed AF; 5,888 with complete data about anti-thrombotic prophylaxis are analyzed here. In the "rhythm strategy" group 45.6% of the CHADS score ≥2 patients (594) were on warfarin, vs. 73.2% (1,741) in the "rate strategy" group (p<0.0001). Overall reasons for warfarin non-use were significantly different in the two groups: clinical contraindications (12.3% vs. 19.7%), side effects (5.5% vs. 8.5%), patients' refusal (12.2% vs. 15.2%), unreliable patient/care-giver (14.4% vs. 25.9%); reasons were unknown to the GP in 55.6% in rhythm control vs. 30.9% in rate control group.

Anti-thrombotic prophylaxis in CHADS ≥2 patients is different in subjects assigned to the Rhythm vs. the Rate control strategy, as well as reported reasons for warfarin non use. GPs do not know why warfarin is not used in a large percentage of cases, mainly in the rhythm control strategy group. Improving efforts should probably be differently tailored for patients assigned to the "rhythm" or the "rate" control strategy.