Utilization and adverse outcomes of percutaneous left atrial appendage closure for stroke prevention in atrial fibrillation in the United States: influence of hospital volume

BACKGROUND

Safety data on percutaneous left atrial appendage closure arises from centers with considerable expertise in the procedure or from clinical trial, which might not be reproducible in clinical practice. We sought to estimate the frequency and predictors of adverse outcomes and costs of percutaneous left atrial appendage closure procedure in the US.

METHODS AND RESULTS

The data were obtained from the Nationwide Inpatient Sample from the years 2006 to 2010. The Nationwide Inpatient Sample is the largest all-payer inpatient data set in the US. Complications were calculated using patient safety indicators and International Classification of Diseases-Ninth Revision, Clinical Modification codes. Annual hospital volume was calculated using unique hospital identifiers. Weights provided by the Nationwide Inpatient Sample were used to generate national estimates. A total of 268 (weighted=1288) procedures were analyzed. The overall composite rate of mortality or any adverse event was 24.3% (65), with 3.4% patients required open cardiac surgery after procedure. Average length of stay was 4.61±1.05 days and cost of care was 26,024±34,651. Annual hospital procedural volume was significantly associated with reduced complications and mortality (every unit increase: odds ratio, 0.89; 95% confidence interval, 0.85-0.94; P<0.001), decrease in length of stay (every unit increase: hazard ratio, 0.95; 95% confidence interval, 0.92-0.98; P<0.001) and cost of care (every unit increase: hazard ratio, 0.96; 95% confidence interval, 0.93-0.98; P<0.001).

CONCLUSIONS

Our study demonstrates that the frequency of inhospital adverse outcomes associated with percutaneous left atrial appendage closure is higher in the real-world population than in clinical trials. We also demonstrate that higher annual hospital volume is associated with safer procedures, with lower length of stay and cost.

Balloon mitral valvuloplasty in the United States: a 13-year perspective

BACKGROUND

Incidence and prevalence of mitral stenosis is declining in the US. We performed this study to determine recent trends in utilization, complications, mortality, length of stay, and cost associated with balloon mitral valvuloplasty.

METHODS

Utilizing the nationwide inpatient sample database from 1998 to 2010, we identified patients using the International Classification of Diseases, 9th Revision, Clinical Modification procedure code for "percutaneous valvuloplasty." Patients ≥18 years of age with mitral stenosis were included. Patients with concomitant aortic, tricuspid, or pulmonic stenosis were excluded. Primary outcome included death and procedural complications.

RESULTS

A total of 1308 balloon mitral valvuloplasties (weighted n = 6540) were analyzed. There was a 7.5% decrease in utilization of the procedure from 24.6 procedures/10 million population in 1998-2001 to 22.7 procedures/10 million population in 2008-2010 (P for trend = .098). We observed a 15.9% overall procedural complication rate and 1.7% mortality rate. The procedural complication rates have increased in recent years (P = .001), corresponding to increasing age and burden of comorbidities in patients. The mean cost per admission for balloon mitral valvuloplasty has gone up significantly over the 10 years, from $11,668 ± 1046 in 2001 to $23,651 ± 301 in 2010 (P <.001).

CONCLUSIONS

In a large cross-sectional study of balloon mitral valvuloplasty in the US, we have reported trends of decreasing overall utilization and increasing procedural complication rates and cost over a period of 13 years.

Results of ventricular septal myectomy and hypertrophic cardiomyopathy (from Nationwide Inpatient Sample [1998-2010])

Ventricular septal myomectomy (VSM) is the primary modality for left ventricular outflow tract gradient reduction in patients with obstructive hypertrophic cardiomyopathy with refractory symptoms. Comprehensive postprocedural data for VSM from a large multicenter registry are sparse. The primary objective of this study was to evaluate postprocedural mortality, complications, length of stay (LOS), and cost of hospitalization after VSM and to further appraise the multivariate predictors of these outcomes. The Healthcare Cost and Utilization Project's Nationwide Inpatient Sample was queried from 1998 through 2010 using International Classification of Diseases, Ninth Revision, procedure codes 37.33 for VSM and 425.1 for hypertrophic cardiomyopathy. The severity of co-morbidities was defined using the Charlson co-morbidity index. Hierarchical mixed-effects models were generated to identify independent multivariate predictors of in-hospital mortality, procedural complications, LOS, and cost of hospitalization. The overall mortality was 5.9%. Almost 9% (8.7%) of patients had postprocedural complete heart block requiring pacemakers. Increasing Charlson co-morbidity index was associated with a higher rate of complications and mortality (odds ratio 2.41, 95% confidence interval 1.17 to 4.98, p = 0.02). The mean cost of hospitalization was $41,715 ± $1,611, while the average LOS was 8.89 ± 0.35 days. Occurrence of any postoperative complication was associated with increased cost of hospitalization (+$33,870, p <0.001) and LOS (+6.08 days, p <0.001). In conclusion, the postoperative mortality rate for VSM was 5.9%; cardiac complications were most common, specifically complete heart block. Age and increasing severity of co-morbidities were predictive of poorer outcomes, while a higher burden of postoperative complications was associated with a higher cost of hospitalization and LOS.