Minimizing the gap between expectations and reality of mitral valve repair in infective endocarditis

Association between Volume and Outcomes of Infective Endocarditis Surgery: A Nationwide Cohort Study

BACKGROUND

To determine the relationship between hospital surgical volume and mortality risk and valve repair rate in infective endocarditis (IE) surgery.

METHODS

Using the Taiwan National Health Insurance Research Database (NHIRD), 3873 patients were identified who underwent surgery between 2000 and 2013. The cumulative hospital volume of valve surgery for IE was calculated, and patients were divided into 4 subgroups according to the quartile. Outcomes were mortality and valve repair rate and the cut point of referral excellence.

RESULTS

The distribution of IE surgery has been shifting to lower volume hospitals over the years. The global disease severity (Charlson's Comorbidity Index score [CCI score]) of patients was greater in the lowest volume hospital than in the highest volume hospital (2.4 vs. 2.0). The crude in-hospital mortality rate was 15.8% and 9.4% for the lowest and highest volume hospitals, respectively, with a significant difference (adjusted odds ratio: 1.86, 95% confidence interval: 1.22-2.85) after adjustment of baseline characteristics including the CCI score. The mitral valve (MV) repair rate increased with the increase in cumulative volume. During a mean follow-up period of 4.4 years, 324 (41.9%) and 254 (30.9%) patients died in the lowest and highest volume subgroups, respectively, and the difference was significant (adjusted hazard ratio: 1.59, 95% CI: 1.21-2.10).

CONCLUSIONS

A higher cumulative volume of IE surgery is associated with a lower risk of mortality and a higher likelihood of successful MV repair. Therefore, interfacility transfer to a high-volume hospital may improve outcomes of IE surgery.

Nationwide cohort study of tricuspid valve repair versus replacement for infective endocarditis

OBJECTIVES

The aim of this study was to compare the outcomes of tricuspid valve (TV) repair versus replacement for patients with infective endocarditis (IE).

METHODS

In this nationwide population-based cohort study, we identified 704 patients from Taiwan National Health Insurance Research Database who underwent TV surgery due to IE between 2000 and 2013. Of them, 412 (58.5%) underwent TV repair and 292 (41.5%) underwent TV replacement, and their perioperative and late outcomes were analysed. Confounding was reduced using the inverse probability of treatment weighting on propensity score.

RESULTS

After inverse probability of treatment weighting, the in-hospital mortality rate between the 2 groups was not significantly different. However, patients who received TV repair had lower rates of perioperative complications, including massive blood transfusion, de novo dialysis and deep wound infection; longer ICU and hospital stays; and higher hospital cost. Regarding late outcomes, TV repair was associated with lower risks of all-cause readmission [subdistribution hazard ratio (HR) 0.68, 95% confidence interval (CI) 0.60-0.78; P < 0.001], readmission for adverse liver outcomes (subdistribution HR 0.75, 95% CI 0.58-0.97; P = 0.025), new permanent pacemaker implantation (subdistribution HR 0.27, 95% CI 0.15-0.48; P < 0.001) and all-cause mortality (HR 0.60, 95% CI 0.51-0.71; P < 0.001) than TV replacement.

CONCLUSIONS

For IE, TV repair is associated with better early and late outcomes than TV replacement. A repair-first strategy is recommended for patients with IE for whom TV surgery is indicated.

Mitral valve repair versus replacement in patients with rheumatic heart disease

BACKGROUND

Rheumatic heart disease remains a major cause of cardiovascular death worldwide. Limited real-world nationwide data are available to compare the long-term outcomes between mitral valve repair and replacement in rheumatic heart disease.

METHODS

We identified adult patients with rheumatic heart disease who underwent mitral valve repair or replacement surgery between 2000 and 2013 from Taiwan's National Health Insurance Research Database. Outcomes of interest included operation-related complications, all-cause mortality, and mitral valve reoperation rate. Propensity score matching at a 1:1 ratio was conducted to mitigate possible confounding factors.

RESULTS

A total of 5086 patients with rheumatic heart disease who underwent mitral valve surgery were identified. Of those, 489 (9.6%) and 4597 (90.4%) underwent mitral valve repair and mitral valve replacement, respectively. After propensity score matching was applied, each group had 467 patients. No difference in risk of in-hospital mortality was observed between groups. With a mean follow-up of 6 years, the mitral valve repair group had comparable risks of all-cause mortality with the mitral valve replacement group (33.4% vs 32.5%; hazard ratio, 1.01; 95% confidence interval, 0.81-1.25). However, higher risks of mitral valve reoperation were observed in the mitral valve repair group (subdistribution hazard ratio, 4.32; 95% confidence interval, 2.02-9.23). Previous percutaneous transvenous mitral commissurotomy was identified as a risk factor of mitral valve reoperation in the repair group.

CONCLUSIONS

Among patients with rheumatic heart disease, mitral valve repair is not associated with superior long-term outcomes. Patients should be carefully selected for mitral valve repair because of its higher reoperation rate, particularly those with previous percutaneous transvenous mitral commissurotomy.