Introduction: The choice of an artificial mitral valve (MV) is a crucial clinical decision that affects the long-term survival and quality of life of patients. However, current guidelines recommend selecting MV based on patient age and life expectancy at the time of mitral valve replacement (MVR), without considering the etiology of MV disease. This study aimed to investigate whether MV disease etiology should be considered when choosing a valve for MVR and to evaluate the impact of MV disease etiology on long-term patient survival. Methods: Using data (2002–2018) from Taiwan’s National Health Insurance Research Database, the authors conducted a nationwide retrospective cohort study to compare the biological and mechanical valves in terms of all-cause mortality as the primary outcome. The inverse probability of the treatment weighting method was used to reduce the effects of the confounding factors. The following etiologies were assessed: infective endocarditis, rheumatic heart disease, ischemic mitral regurgitation, and degenerative mitral regurgitation. Results: In patients aged below 70 years, it was observed that mechanical valves demonstrated an association with benefits compared to biological valves in the context of survival. In patients with infective endocarditis aged below 72 years, mechanical valves were associated with survival benefits, but not in those with stroke during hospitalization. These valves were also found to be linked with survival advantages for patients with rheumatic heart disease aged below 60 years and for those with degenerative mitral regurgitation aged below 72 years. However, no age-dependent effects of valve type on all-cause mortality were observed in patients with ischemic mitral regurgitation. Conclusion: The etiology of MV disease appears to be important in the selection of a suitable MV and determination of a cutoff age for mechanical and biological MVR.

Patients undergoing complex spine surgery present with multilevel spinal involvement, advanced age, and multiple comorbidities. Surgery is associated with significant blood loss and remarkable hemodynamic changes. The present study aimed to investigate the accuracy and trending ability of a non-invasive continuous method to monitor hemoglobin (SpHb) concentrations using a Radical-7™ Pulse CO-Oximeter in complex spine surgery. Forty-nine patients who underwent complex spine surgery were enrolled in this prospective observational study. Multiple time points were established for data collection throughout the operation. Simultaneous SpHb–total hemoglobin (tHb) paired data were recorded for analyses. Linear regression analysis, Bland–Altman plot, four-quadrant plot, and Critchley polar plot were used to assess the accuracy and trending ability of the monitor. A total of 272 pairs of SpHb-tHb data were available and were divided into two groups based on the perfusion index (PI): PI values ≥1.0 (n = 200) and PI values < 1.0 (n = 72). The correction coefficients (r) between SpHb and tHb were 0.6946 and 0.6861 in the groups with PI values ≥1.0 and < 1.0, respectively (P < 0000.1). In the ≥1.0 group, the mean bias was − 0.21 g/dL and the percentage error (PE) was 15.85%, whereas in the < 1.0 group, the mean bias was − 0.04 g/dL and the PE was 17.42%. Four-quadrant plot revealed a concordance rate of 85.11%, whereas the Critchley polar plot showed a concordance rate of 67.21%. The present study demonstrates the acceptable accuracy of the Radical-7™ Pulse CO-Oximeter even with a low PI. However, the trending ability was limited and unsatisfactory.