Effects of mitral valve disease etiology on the outcomes of mechanical and biological valve replacement: retrospective cohort study.

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.

Sex Differences in Epidemiological Distribution and Outcomes of Surgical Mitral Valve Disease.

BACKGROUND: Mitral valve (MV) disease is the most common form of valvular heart disease. Findings that indicate women have a higher risk for unfavorable outcomes than men remain controversial. This study aimed to determine the sex-based differences in epidemiological distributions and outcomes of surgery for MV disease.Methods and Results: Overall, 18,572 patients (45.3% women) who underwent MV surgery between 2001 and 2018 were included. Outcomes included in-hospital death and all-cause mortality during follow up. Subgroup analysis was conducted across different etiologies, including infective endocarditis (IE), degenerative, ischemic, and rheumatic mitral pathology. The overall MV repair rate was lower in women than in men (20.5% vs. 30.6%). After matching, 6,362 pairs (woman : man=1 : 1) of patients were analyzed. Women had a slightly higher risk for in-hospital death than men (10.8% vs. 9.8%; odds ratio [OR]: 1.11, 95% confidence interval [CI]: 0.99-1.24; P=0.075). Women tended to have a higher incidence of de novo dialysis (9.8% vs. 8.6%; P=0.022) and longer intensive care unit stay (8 days vs. 7.1 days; P<0.001). Women with IE had poorer in-hospital outcomes than men; however, there were no sex differences in terms of all-cause mortality. CONCLUSIONS: Sex-based differences of MV intervention still persist. Although long-term outcomes were comparable between sexes, women, especially those with IE, had worse perioperative outcomes than men.

Mitral Valve Repair vs. Replacement by Different Etiologies　- A Nationwide Population-Based Cohort Study.

BACKGROUND: When mitral valve (MV) surgery is indicated, repair is preferred over replacement; however, this preference is not supported by evidence from clinical trials. Furthermore, the benefits of MV repair may not be universal for all etiologies of MV disease.Methods and Results: This study identified a total of 18,428 patients who underwent MV repair (n=4,817) or MV replacement (n=13,611) during 2001-2018 from Taiwan's National Health Insurance Research Database. These patients were classified into 4 etiologies: infective endocarditis (IE, n=2,678), rheumatic heart disease (RHD, n=4,524), ischemic mitral regurgitation (IMR, n=3,893), and degenerative mitral regurgitation (DMR, n=7,333). After propensity matching, all-cause mortality during follow-up was lower among patients receiving MV repair than among patients receiving MV replacement in the IE, IMR, and DMR groups (hazard ratio [HR]=0.72, 95% confidence interval [CI]: 0.55-0.93; HR=0.82, 95% CI: 0.73-0.92; and HR 0.73, 95% CI: 0.64-0.84, respectively). However, in the RHD group, the MV reoperation rate was higher after MV repair than after MV replacement (subdistribution HR=1.91, 95% CI: 1.02-3.55). CONCLUSIONS: In comparison with MV replacement, MV repair was associated with a lower late mortality in patients with IE, IMR, and DMR, and a higher risk of reoperation in patients with RHD.

Mechanical Versus Bioprosthetic Aortic Valve Replacement in Patients Undergoing Bentall Procedure.

BACKGROUND: The widely used Bentall procedure is the criterion standard treatment for aortic root pathology. Studies comparing the long-term outcomes of bioprosthetic and mechanical valves in patients undergoing the Bentall procedure are limited. METHODS AND RESULTS: Patients who underwent the Bentall procedure with a bioprosthetic or mechanical valve between 2001 and 2018 were identified from Taiwan's National Health Insurance Research Database. The primary outcome of interest was all-cause mortality. Inverse probability of treatment weighting was performed to compare the 2 prosthetic types. In total, 1052 patients who underwent the Bentall procedure were identified. Among these patients, 351 (33.4%) and 701 (66.6%) chose bioprosthetic and mechanical valves, respectively. After inverse probability of treatment weighting, no significant differences in the in-hospital mortality (odds ratio, 0.96 [95% CI, 0.77-1.19]; P=0.716) and all-cause mortality (34.1% vs. 38.1%; hazard ratio, 0.90 [95% CI, 0.78-1.04]; P=0.154) were observed between the groups. The benefits of relative mortality associated with mechanical valves were apparent in younger patients and persisted until ≈50 years of age. CONCLUSIONS: No differences in survival benefits were observed between the valves in patients who underwent the Bentall procedure. Additionally, bioprosthetic valves may be a reasonable choice for patients aged >50 years when receiving the Bentall procedure in this valve-in-valve era.

Surgical volume and outcomes of surgical ablation for atrial fibrillation: a nationwide population-based cohort study.

BACKGROUND: Atrial fibrillation is the most common cardiac arrythmia and causes many complications. Sinus rhythm restoration could reduce late mortality of atrial fibrillation patients. The Maze procedure is the gold standard for surgical ablation of atrial fibrillation. Higher surgical volume has been documented with favorable outcomes of various cardiac procedures such as mitral valve surgery and aortic valve replacement. We aimed to determine the volume-outcome relationship (i.e., association between surgical volume and outcomes) for the concomitant Maze procedure during major cardiac surgeries. METHODS: This nationwide population-based cohort study retrieved data from the Taiwan National Health Insurance Research Database. Adult patients undergoing concomitant Maze procedures during 2010-2017 were identified; consequently, 2666 patients were classified into four subgroups based on hospital cumulative surgery volumes. In-hospital outcomes and late outcomes during follow-up were analyzed. Logistic regression and Cox proportional hazards model were used to analyze the volume-outcome relationship. RESULTS: Patients undergoing Maze procedures at lower-volume hospitals tended to be frailer and had higher comorbidity scores. Patients in the highest-volume hospitals had a lower risk of in-hospital mortality than those in the lowest-volume hospitals [adjusted odds ratio, 0.30; 95% confidence interval (CI), 0.15-0.61; P < 0.001]. Patients in the highest-volume hospitals had lower rates of late mortality than those in the lowest-volume hospitals, including all-cause mortality [adjusted hazard ratio (aHR) 0.53; 95% CI 0.40-0.68; P < 0.001] and all-cause mortality after discharge (aHR 0.60; 95% CI 0.44-0.80; P < 0.001). CONCLUSIONS: A positive hospital volume-outcome relationship for concomitant Maze procedures was demonstrated for in-hospital and late follow-up mortality. The consequence may be attributed to physician skill/experience, experienced multidisciplinary teams, and comprehensive care processes. We suggest referring patients with frailty or those requiring complicated cardiac surgeries to high-volume hospitals to improve clinical outcomes. TRIAL REGISTRATION: the institutional review board of Chang Gung Memorial Hospital approved all data usage and the study protocol (registration number: 202100151B0C502).

Sex differences in risks of in-hospital and late outcomes after cardiac surgery: a nationwide population-based cohort study.

OBJECTIVES: Outcomes of sex differences in major cardiac surgery remain controversial. A comprehensive understanding of sex differences in major adult cardiac surgery could provide better knowledge of risk factors, management strategy and short-term or long-term outcomes. The present study aimed to investigate sex differences in the risks of outcomes of major cardiac surgeries and subgroup analyses of different valve types. DESIGN: Population-based nationwide cohort study. SETTING: Data were obtained from National Health Insurance Research Database (NHIRD) in Taiwan. PARTICIPANTS: A total of 66 326 adult patients (age ≥20 years; 30.3% women) who underwent a first major cardiac surgery (isolated coronary artery bypass graft (CABG), isolated valve or concomitant bypass/valve) from 2000 to 2013 were identified via Taiwan NHIRD. MAIN OUTCOME MEASURES: Outcomes of primary interest were in-hospital death and all-cause mortality during follow-up period. Propensity score matching was conducted as a secondary analysis for the sensitivity test. RESULTS: Women who underwent isolated CABG tended to have greater risks of both in-hospital (OR 1.37; 95% CI 1.26 to 1.49) and late outcomes (HR 1.26; 95% CI 1.22 to 1.31). Women after concomitant CABG/valve also had a greater in-hospital (OR 1.19; 95% CI 1.01 to 1.40) and long-term mortality (HR 1.14; 95% CI 1.05 to 1.24). Women after isolated mitral valve repair have a non-favourable outcome of in-hospital mortality (OR 1.70; 95% CI 1.01 to 2.87). Women who did not receive an isolated aortic valve replacement had more favourable all-cause mortality outcome (HR 0.90; 95% CI 0.84 to 0.96). Secondary analysis in the propensity score-matching cohort demonstrated results similar to the primary analysis. CONCLUSIONS: Female patients who underwent procedures involving CABG (with or without concurrent valvular intervention) had generally worse outcomes. However, the results of isolated valve surgery were variable on the basis of the type of intervened valve.

Increased FIO2 influences SvO2 interpretation and accuracy of Fick-based cardiac output assessment in cardiac surgery patients: A prospective randomized study.

INTRODUCTION: The study aimed to reveal how the fraction of inspired oxygen (FIO2) affected the value of mixed venous oxygen saturation (SvO2) and the accuracy of Fick-equation-based cardiac output (Fick-CO). METHODS: Forty two adult patients who underwent elective cardiac surgery were enrolled and randomly divided into 2 groups: FIO2 < 0.7 or >0.85. Under stable general anesthesia, thermodilution-derived cardiac output (TD-CO), SvO2, venous partial pressure of oxygen, hemoglobin, arterial oxygen saturation, arterial partial pressure of oxygen, and blood pH levels were recorded before surgical incision. RESULTS: Significant differences in FIO2 values were observed between the 2 groups (0.56 ±â€Š0.08 in the <70% group and 0.92 ±â€Š0.03 in the >0.85 group; P < .001). The increasing FIO2 values lead to increases in SvO2, venous partial pressure of oxygen, and arterial partial pressure of oxygen, with little effects on cardiac output and hemoglobin levels. When comparing to TD-CO, the calculated Fick-CO in both groups had moderate Pearson correlations and similar linear regression results. Although the FIO2 <0.7 group presented a less mean bias and a smaller limits of agreement, neither group met the percentage error criteria of <30% in Bland-Altman analysis. CONCLUSION: Increased FIO2 may influence the interpretation of SvO2 and the exacerbation of Fick-CO estimation, which could affect clinical management. TRIAL REGISTRATION: ClinicalTrials.gov ID number: NCT04265924, retrospectively registered (Date of registration: February 9, 2020).

Validity of accuracy and trending ability of non-invasive continuous total hemoglobin measurement in complex spine surgery: a prospective cohort study.

BACKGROUND: 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. METHODS: 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. RESULTS: 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%. CONCLUSIONS: 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.