Biological versus mechanical prosthesis in 3279 patients from the Swedish in-patients register

Abstract

Objectives. To compare valve-related morbidity among patients aged <70 and ≥70 years, receiving either a mechanical or a biological prosthesis in a population-based setting. Design. In total, 3279 patients (21 644 patient-years) were followed up through the Swedish National In-Patients Register, which registers all hospital admissions. Death, thromboembolism, bleeding, endocarditis, valve thrombosis and reoperations were all captured. Results. Survival was lower among patients aged <70 years with a bioprosthesis compared to a mechanical prosthesis (p < 0.0001), but equal among older patients. A mechanical prosthesis indicated a lower risk (p < 0.001) of thromboembolism (1.5% per patient year, ppy), than bioprosthesis (2.6% ppy), irrespective of age. Bleeding was increased (p = 0.002) with a mechanical prosthesis (1.7% ppy) compared to a bioprosthesis (1.1% ppy); the risk of bleeding increased early (<5 years) whereas thromboembolism increased late (>5 years). Event-free survival was higher in younger patients with a mechanical prosthesis compared to bioprosthesis recipients (p < 0.001), but equal among older patients. Conclusions. Survival was comparable in older patients irrespective of prosthesis type. Bleeding was increased with a mechanical prosthesis, especially in the elderly. The risk of thromboembolism was higher in patients with a bioprosthesis.

Key words::

• Heart valve surgery
• mechanical prosthesis
• biological prosthesis
• in-patients register
• valve-related morbidity
• valve prosthesis

Acknowledgements

Financial support for this study was provided by the Swedish Heart Lung Foundation. The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.