Introduction Aortic Valve Replacement (AVR) is most commonly performed using Mechanical or Tissue Valves. Benefits of Mechanical Valve include their durability (freedom from long-term structural deterioration); however patients need life-long warfarin. Patients with tissue valves do not need warfarin, but are at risk of structural valve deterioration 8 to 12 years postoperatively; this may need repeat surgery. Surgeons therefore use age as the most important criteria to determine type of valve to implant. In general, patients <65 years of age receive mechanical valves, and patients >75 years of age receive tissue valves. In patients between 65 and 75 years of age, it is a matter of clinical judgement. The aim of this study was to identify differences in perioperative and medium-term mortality, warfarin use, incidence of bleeding complications, and Quality of Life between recipients of mechanical vs tissue valves.
Methods Six hundred and ninety eight patients underwent AVR (with or without concomitant CABG) between April 2002 and March 2006. Perioperative and immediate postoperative data were obtained from the departmental database. Current status (Alive/Dead) was obtained from the Scottish General Register's Office. All living patients were sent the SF36, and EuroQOL5D questionnaires, with additional questions regarding warfarin use, and bleeding complications.
Results Mean follow-up time was 5.02 years for tissue valves, and 5.12 years for mechanical valves. In patients <65 years, mechanical valve recipients had a significantly lower hospital mortality (0% vs 5%: p=0.01). In the 65 to 75 age group, patients with mechanical valves had a lower 5-year mortality (11% vs 21%; p=0.02) and better QOL (mental component) (p=0.03). Sixteen per cent of tissue valve recipients in the 65–75 year age group were on warfarin at 5-year follow-up. There was no difference in the incidence of hemorrhagic complications between the two groups at 5 years follow-up.
Conclusions In the 65 to 75 year age group, mechanical valve recipients had a better 5-year survival, and Quality of Life. There was no significant difference between the incidence of hemorrhagic complications in the two groups. This should be kept in mind during discussions regarding choice of prostheses.
- Aortic valve replacement
- medium-term follow-up