Warfarin Initiation in Mechanical Mitral Valve Replacement Patients

Inpatients of The Cardiovascular hospital who had undergone mitral heart valve replacement with a mechanical prosthesis and commencing warfarin were eligible for inclusion. Patients were included after they had newly undergone elective surgery for implantation of mechanical mitral heart valves, had commenced on warfarin, received enoxaparin as a bridging agent and had INR monitored for a minimum of 4 consecutive days after warfarin initiation. A total of 50 consecutive MVR patients were recruited. Each was assigned to either the group I (25 patients) or the group II (25 patients) group. All patients received the conventional postoperative treatment including: Diuretics, beta-blockers, digoxin or heart rate-regulating calcium channel blockers and anticoagulation bridging therapy using LMWH according to the European Society of Cardiology (ESC) Guidelines for the management of MVR and antibiotic for 48hour after surgery according to the investigator's hospital's antibiotic protocol. Baseline evaluation included demographics and history taking. After obtaining the informed consent, information including age, weight, height, smoking state, and other diseases e.g. hypertension, diabetes, hyperlipidemias, etc. were documented for each patient. Medication history in details, as well as the background cardiovascular treatment was considered. Blood samples were withdrawn from patients for evaluation of INR. Complete blood count, kidney and liver function tests were performed as part of the routine admission care. All patients were followed up daily post operative till reaching an in range INR value. All patients were observed daily for INR values and dose adjusted accordingly and also estimation of incidence and severity of bleeding complications was done.