Anticoagulation Control and Major Adverse Clinical Events in Patients with Operated Valvular Heart Disease with and without Atrial Fibrillation Receiving Vitamin K Antagonists.

BACKGROUND

Good quality anticoagulation among patients with operated valvular heart disease is needed to reduce ischaemic and thromboembolic complications. There is limited evidence regarding factors that affect anticoagulation control in patients implanted with mechanical or tissue prosthetic valve(s).

AIM

To examine the quality of and factors that affect anticoagulation control, major adverse clinical events and all-cause death in operated valvular heart disease patients with and without atrial fibrillation who are receiving a vitamin K antagonist.

METHODS

Quality of anticoagulation were retrospectively assessed among 456 operated valvular heart disease patients [164 (36%) with AF and 290 (64%) without AF] via time in therapeutic range (TTR) (Rosendaal method) and percentage of INRs in range (PINRR) over a median of 6.2 (3.3-8.5) years. VHD was defined by the presence of a mechanical or tissue prosthetic valve at the mitral, aortic, or both sites.

RESULTS

Mean age 51 (14.7), 64.5% men. Most (96.1%) had a mechanical prosthesis and 64% had aortic valve replacement. Overall, mean TTR was 58.5% (14.6) and PINRR was 50.1% (13.8). Operated valvular heart disease patients with AF had significantly lower mean TTR and PINRR (TTR: 55.7% (14.2) vs. 60.1% (14.6); = 0.002, respectively, PINRR: 47.4% (13.5) vs. 51.6% (13.7); = 0.002, respectively), and a lower proportion of TTR ≥ 70%, despite a similar number of INR tests compared to those without AF. Predictors of TTR < 70% were female sex, AF and anaemia/bleeding history. Significantly higher proportions of operated valvular heart disease patients with AF died (20.7% vs. 5.8%; < 0.001), but ≥1 MACE rates were similar between the two groups.

CONCLUSIONS

Operated valvular heart disease patients with AF at baseline have poorer anticoagulation control compared to those without AF. The presence of concomitant AF, anaemia/bleeding history and female sex independently predicted poor TTR. Stringent INR monitoring is needed to improve anticoagulation control and prevent major adverse clinical events in patients with operated valvular heart disease.