ABC | Volume 112, Nº3, March 2019

Original Article Kiyose et al A systematic review for valvular prostheses Arq Bras Cardiol. 2019; 112(3):292-301 Figure 3 – Forest plots showing the effects of biological versus mechanical prostheses on a need for reoperation (A) and risk of bleeding (B). 13.3% 14.6% 17.1% 44.9% 11.4% 6.8% 46.2% 64.4% 10.1% 1.6% 20.1% 31.8% 3.8% 3.8% 100.0% 19.4% 1.9% 20.3% 41.7% 13.4% 13.4% 100.0% 7.59 [3.26, 17.71] 3.74 [1.71, 8.20] 2.90 [1.47, 5.71] 4.17 [2.41, 7.21] 5.79 [3.19, 10.50] 1.89 [0.12, 29.46] 2.00 [1.14, 3.52] 3.21 [1.30, 7.92] 2.93 [1.26, 6.80] 2.93 [1.26, 6.80] 3.60 [2.44, 5.32] 0.69 [0.38, 1.28] 0.49 [0.22, 1.08] 0.59 [0.43, 0.80] 0.59 [0.46, 0.77] 0.70 [0.37, 1.34] 0.95 [0.18, 4.94] 0.58 [0.37, 0.93] 0.63 [0.44, 0.91] 2.01 [0.70, 5.80] 2.01 [0.70, 5.80] 0.64 [0.52, 0.78] 1.5.1 Aortic valve Edinburgh 2003 Stassano 2009 Veterans Affairs 2000 Subtotal (95% CI) Test for overall effect: Z = 5.09 (p < 0.00001) Heterogeneity: Tau 2 = 0.08; Chi 2 = 3.09, df = 2 (p = 0.21); I 2 = 35% 1.5.2 Mitral valve Edinburgh 2003 Vallejo 1981 Veterans Affairs 2000 Subtotal (95% CI) Test for overall effect: Z = 2.53 (p = 0.01) Heterogeneity: Tau 2 = 0.38; Chi 2 = 6.60, df = 2 (p = 0.04); I 2 = 70% 1.5.3 Mitral + aortic valve Edinburgh 2003 Subtotal (95% CI) Test for overall effect: Z = 2.50 (p = 0.01) Heterogeneity: Not applicable 1.2.3 Mitral + aortic valve Edinburgh 2003 Subtotal (95% CI) Test for overall effect: Z = 1.29 (p = 0.20) Heterogeneity: Not applicable Total (95 CI) Test for overall effect: Z = 6.46 (p = 0.00001) Test for subgroup differences: Chi 2 = 0.56, df = 2 (p = 0.76); I 2 = 0% Heterogeneity: Tau 2 = 0.11; Chi 2 = 10.41, df = 6 (p = 0.11); I 2 = 42% Total (95 CI) Test for overall effect: Z = 4.32 (p < 0.0001) Test for subgroup differences: Chi 2 = 4.82, df = 2 (p = 0.09); I 2 = 58.5% Heterogeneity: Tau 2 = 0.00; Chi 2 = 5.74, df = 6 (p = 0.45); I 2 = 0% 1.2.1 Aortic valve Edinburgh 2003 Stassano 2009 Veterans Affairs 2000 Subtotal (95% CI) Test for overall effect: Z = 3.98 (p < 0.0001) Heterogeneity: Tau 2 = 0.00; Chi 2 = 0.48, df = 2 (p = 0.79); I 2 = 0% 1.2.2 Mitral valve Edinburgh 2003 Vallejo 1981 Veterans Affairs 2000 Subtotal (95% CI) Test for overall effect: Z = 2.44 (p = 0.01) Heterogeneity: Tau 2 = 0.00; Chi 2 = 0.44, df = 2 (p = 0.80); I 2 = 0% 0.1 0.2 0.5 1 2 5 10 Favours biological Favours mechanical 0.1 0.2 0.5 1 2 5 10 Favours biological Favours mechanical A Need for Reoperation B Bleeding Study or Subgroup Weight Risk Ratio Risk Ratio IV, Random, 95% CI IV, Random, 95% CI Study or Subgroup Weight Risk Ratio Risk Ratio IV, Random, 95% CI IV, Random, 95% CI to have access to high-quality data to inform decisions regarding the use of health technologies. Therefore, more and better trials comparing technologies for patients with valvular heart disease are needed and feasible. Funding for those trials might be provided by the prosthesis industry had the regulatory environment enforced formal comparative testing, as is currently done with drugs. Alternatively, public funding agencies might support these trials. Evidence Applicability Bleeding was more common in the mechanical prosthesis group than in the biological prosthesis group. However, the studies included in the present review were conducted at a time predating the International Normalised Ratio (INR) and the International Sensitivity Index (ISI). The INR was introduced in the 1980s, and the ISI was introduced in the 1990s. It is possible that with the improved anticoagulation 297