Self management of oral anticoagulant therapy after heart valve replacement

• Published in: European journal of cardio-thoracic surgery 1997-05, Vol.11 (5), p.935-942
• Main Authors: HASENKAM, J. M, KIMOSE, H. H, KNUDSEN, L, GRØNNESBY, H, HALBORG, J, CHRISTENSEN, T. D, ATTERMANN, J, PILEGAARD, H. K
• Format: Article
• Language: English
• Subjects: Administration, Oral; Adult; Aged; Anticoagulants - administration & dosage; Anticoagulants - therapeutic use; Biological and medical sciences; Blood Coagulation Tests - methods; Blood Specimen Collection; Blood. Blood coagulation. Reticuloendothelial system; Case-Control Studies; Feasibility Studies; Female; Follow-Up Studies; Heart Valve Prosthesis; Humans; Male; Medical sciences; Middle Aged; Pharmacology. Drug treatments; Postoperative Care; Self Administration; Self Care; Time Factors
• ISSN: 1010-7940; 1873-734X
• DOI: 10.1016/S1010-7940(97)01204-9

OBJECTIVE: Patients with mechanical heart valves require lifelong oralanticoagulant treatment which entails frequent blood sampling and dosageadjustment. The purpose of this study was to investigate the feasibility ofletting heart valve operated patients manage blood specimen analysis anddosage adjustment themselves. METHODS: A total of 21 patients were enrolledin the study and followed for at least 9 months postoperatively.Immediately after the heart valve operation they were trained in operatinga CoaguChek international normal ratio (INR) monitor to analyze capillarywhole blood samples. Subsequently training in dosage adjustment wasaccomplished and all patients were considered fully capable of selfmanagement after 30 weeks. In the training period, parallel laboratory INRmeasurements were made at 3-4 week intervals for reference. A control groupof 20 patients was matched, respectively, to the study group. The INRtarget range was 2.0- 3.0. RESULTS: Out of the 21 study patients 19continued self management beyond 9 months. The median INR value obtainedwith the monitor was within therapeutic target range for all study patientsand only 15 out of 20 control patients were within this range. The meansystematic deviation between laboratory and CoaguChek INR was 7.8% but eachpatient had a constant characteristic deviation from -11 to +21%. The studypatients were within therapeutic target range 77% of the time compared with53% for the control patients. CONCLUSIONS: Self management of oralanticoagulation is feasible for selected patients and constitutes asignificant service improvement compared with conventional management. TheCoaguChek monitor seems sufficiently accurate and reliable for self testingand the treatment quality is comparable or even better than conventionalmanagement. Assessment of the rate of bleeding and thrombo-embolic eventsshall be settled in studies comprising larger number of patients.