Income, Geography, and Etiology as Factors Associated with Valve Replacement Outcomes: A Nationwide Cohort of 63,426 Patients in a Middle-Income Country.

The overall in-hospital mortality rate after valve replacement surgery in Brazil's public health system was 8.6% and the five-year mortality was 30.1%.

• The cohort included 63,426 patients with a mean age of 56.9 ± 15.2 years.
• Median follow-up was 1,023 days.
• The study covered valve replacement surgeries performed between January 2015 and December 2024.
• These mortality rates are described as substantially worse than those reported in wealthier countries.

Higher income was significantly associated with lower post-surgical mortality compared to the lowest income quartile.

• The highest income quartile had a hazard ratio of 0.82 (95% CI 0.76–0.89; p < 0.001) compared to the lowest income quartile in the adjusted Cox model.
• The association between income and survival was assessed after adjustment for other covariates.
• Income was operationalized using the IVS Atlas social vulnerability index linked to individual patient records.

Geographic location was significantly associated with in-hospital mortality, with mortality exceeding 25% in low-volume municipalities in the North region of Brazil.

• In-hospital mortality exceeded 25% in low-volume municipalities located in Brazil's North region.
• Geography was identified as a significant independent factor associated with survival.
• Patients living in regions with fewer surgical centers faced higher mortality.
• The study used Brazil's universal health system data to capture nationwide geographic variation.

Reoperation was associated with significantly worse survival compared to primary valve replacement surgery.

• Reoperation had a hazard ratio of 1.48 (95% CI 1.37–1.58; p < 0.001) in the adjusted Cox model.
• The association was statistically significant and clinically meaningful in magnitude.
• Reoperation was identified as a valve-specific risk factor in the multivariable survival analysis.

Valve lesion subtype predicted outcomes differentially across time horizons.

• Disease etiology was identified as an important factor associated with survival after valve replacement.
• Rheumatic heart disease remains a major etiology in Brazil and other low- and middle-income countries.
• The differential predictive value of valve lesion subtype varied depending on the time horizon examined (early vs. late mortality).
• The study notes that cardiac surgical capacity in LMICs covers less than 2% of estimated need.

Five Brazilian public health databases were successfully linked to create an individual-level longitudinal cohort, with a proof-of-life algorithm applied to correct right-censoring bias.

• Databases linked included outpatient care (SIA), hospital admissions (SIH), mortality records (SIM), the cancer registry (RHC), and the social vulnerability index (IVS Atlas).
• A proof-of-life algorithm was implemented specifically to correct right-censoring bias in survival analyses.
• The resulting cohort of 63,426 patients represents a nationwide population-level dataset.
• The authors describe this linkage framework as 'a scalable model for cardiovascular outcome surveillance in resource-constrained settings.'

Population-level outcome data after valve surgery in low- and middle-income countries (LMICs) are described as virtually absent prior to this study.

• Heart valve disease is characterized as a growing cause of mortality and disability worldwide, disproportionately burdening LMICs.
• Rheumatic heart disease remains a major etiology in LMICs.
• Cardiac surgical capacity in LMICs covers less than 2% of the estimated need.
• The authors position Brazil's universal health system as enabling this otherwise unavailable population-level analysis.