Impact of Annual Hospital Volume on Outcomes after Left Ventricular Assist Device (LVAD) Implantation in the Contemporary Era.

INTRODUCTION: There are few data in the literature regarding impact of annual hospital volume on outcomes such as mortality and length of stay (LOS) post-LVAD implantation. METHODS: We queried the nationwide inpatient sample from 2008 to 2011 using International Classification of Diseases, 9th Revision procedure code 37.66. We included patients ≥18 years without primary diagnosis of orthotopic heart transplant. Annual volume of LVAD implantation was computed for each hospital. Multivariable hierarchical mixed effect logistic regression models were used to determine predictors of in-hospital mortality and LOS. RESULTS: There were 1749 LVAD implants from 2008 to 2011; patients had a mean age of 55.4 years, and 23% were female. In-hospital mortality decreased from 20.9% in the first tertile (1-22 LVADs/y) to 13.7% in the third tertile (≥35 LVADs/y) of hospital volume. Median LOS decreased from 34 days in the first tertile to 28 days in third tertile of hospital volume. The adjusted odds ratios of the highest tertile of hospital volume in predicting in-hospital mortality and LOS were 0.41 (0.26-0.64, P < .001) and 0.41 (0.23-0.73, P = .003), respectively. Restricted cubic spline analysis showed that a volume threshold of >20 LVADs/year was associated with favorable mortality rates of <10%. CONCLUSIONS: High annual LVAD volume is associated with significantly decreased in-hospital mortality and LOS after LVAD implantation. Center experience is an important determinant of optimal patient outcomes.

Impact of Glycoprotein IIb/IIIa Inhibitors Use on Outcomes After Lower Extremity Endovascular Interventions From Nationwide Inpatient Sample (2006-2011).

OBJECTIVE: The aim of our study was to study the impact of glycoprotein IIb/IIIa inhibitors (GPI) on in-hospital outcomes. BACKGROUND: There is paucity of data regarding the impact of GPI on the outcomes following peripheral endovascular interventions. METHODS: The study cohort was derived from Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample (NIS) database between the years 2006 and 2011. Peripheral endovascular interventions and GPI utilization were identified using appropriate ICD-9 Diagnostic and procedural codes. Two-level hierarchical multivariate mixed models were created. The study outcomes were: primary (in-hospital mortality and amputation studied separately) and secondary (composite of in-hospital mortality and postprocedural complications). Hospitalization costs were also assessed. RESULTS: GPI utilization (OR, 95% CI, P-value) was independently predictive of lower amputation rates (0.36, 0.27-0.49, <0.001). There was no significant difference in terms of in-hospital mortality (0.59, 0.31-1.14, P 0.117), although GPI use predicted worse secondary outcomes (1.23, 1.03-1.47, 0.023). Following propensity matching, the amputation rate was lower (3.2% vs. 8%, P < 0.001), while hospitalization costs were higher in the cohort that received GPI ($21,091 ± 404 vs. 19,407 ± 133, P < 0.001). CONCLUSIONS: Multivariate analysis revealed GPI use in peripheral endovascular interventions to be suggestive of an increase in composite end-point of in-hospital mortality and postprocedural complications, no impact on in-hospital mortality alone, significantly lower rate of amputation, and increase in hospitalization costs. © 2016 Wiley Periodicals, Inc.

Variability in utilization of drug eluting stents in United States: Insights from nationwide inpatient sample.

OBJECTIVES: We studied the trends and predictors of drug eluting stent (DES) utilization from 2006 to 2011 to further expound the inter-hospital variability in their utilization. BACKGROUND: We queried the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample (NIS) between 2006 and 2011 using ICD-9-CM procedure code, 36.06 (bare metal stent) or 36.07 (drug eluting stents) for Percutaneous Coronary Intervention (PCI). Annual hospital volume was calculated using unique identification numbers and divided into quartiles for analysis. METHODS AND RESULTS: We built a hierarchical two level model adjusted for multiple confounding factors, with hospital ID incorporated as random effects in the model. About 665,804 procedures (weighted n = 3,277,884) were analyzed. Safety concerns arising in 2006 reduced utilization DES from 90% of all PCIs performed in 2006 to a nadir of 69% in 2008 followed by increase (76% of all stents in 2009) and plateau (75% in 2011). Significant between-hospital variation was noted in DES utilization irrespective of patient or hospital characteristics. Independent patient level predictors of DES were (OR, 95% CI, P-value) age (0.99, 0.98-0.99, <0.001), female(1.12, 1.09-1.15, <0.001), acute myocardial infarction(0.75, 0.71-0.79, <0.001), shock (0.53, 0.49-0.58, <0.001), Charlson Co-morbidity index (0.81,0.77-0.86, <0.001), private insurance/HMO (1.27, 1.20-1.34, <0.001), and elective admission (1.16, 1.05-1.29, <0.001). Highest quartile hospital (1.64, 1.25-2.16, <0.001) volume was associated with higher DES placement. CONCLUSION: There is significant between-hospital variation in DES utilization and a higher annual hospital volume is associated with higher utilization rate of DES. © 2015 Wiley Periodicals, Inc.

Septal Ablation and Hypertrophic Obstructive Cardiomyopathy: 7 Years US Experience.

BACKGROUND: Septal ablation (SA) is a key modality for left ventricular outflow tract gradient reduction in hypertrophic obstructive cardiomyopathy (HOCM) patients with refractory symptoms. The primary objective of our study was to evaluate post-procedural mortality, complications, length of stay (LOS), and cost of hospitalization following SA. METHODS: We queried the Nationwide Inpatient Sample (NIS) between 2005 and 2011 using the ICD9 procedure code of 37.34 for ablation of heart tissue. Only adult patients with HOCM (ICD-9-CM: 425.1) were included. Patients with any arrhythmia diagnosis or open surgical ablation procedure code were excluded. Hierarchical mixed effects models were generated in order to identify the independent multivariate predictors of outcomes. RESULTS: A total of 358 SAs were available for analysis. There was no reported mortality during the study period; permanent pacemaker implantation rate was 8.7%. Highest hospital volume tertile (OR, 95%CI, P- value) predicted significantly lower post-procedural complications (0.51, 0.26-0.98, P = 0.04). Univariate analysis of highest versus lowest tertile of hospital volume showed significant decrease in LOS (2.6 days vs. 3.8 days, P<0.01) and non-significant decrease hospitalization costs (16,800$ vs. 19,500$, P = 0.29). CONCLUSIONS: SA is a safe procedure and associated with low peri- procedural mortality rate. A higher burden of baseline comorbidities is associated with worse outcomes while higher annual hospital volume is associated with lower rate of post-procedural complications, length of stay, and cost of care following SA.

Contemporary trends of hospitalization for atrial fibrillation in the United States, 2000 through 2010: implications for healthcare planning.

BACKGROUND: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. The associated morbidity and mortality make AF a major public health burden. Hospitalizations account for the majority of the economic cost burden associated with AF. The main objective of this study is to examine the trends of AF-related hospitalizations in the United States and to compare patient characteristics, outcomes, and comorbid diagnoses. METHODS AND RESULTS: With the use of the Nationwide Inpatient Sample from 2000 through 2010, we identified AF-related hospitalizations using International Classification of Diseases, 9th Revision, Clinical Modification code 427.31 as the principal discharge diagnosis. Overall AF hospitalizations increased by 23% from 2000 to 2010, particularly in patients ≥65 years of age. The most frequent coexisting conditions were hypertension (60.0%), diabetes mellitus (21.5%), and chronic pulmonary disease (20.0%). Overall in-hospital mortality was 1%. The mortality rate was highest in the group of patients ≥80 years of age (1.9%) and in the group of patients with concomitant heart failure (8.2%). In-hospital mortality rate decreased significantly from 1.2% in 2000 to 0.9% in 2010 (29.2% decrease; P<0.001). Although there was no significant change in mean length of stay, mean cost of AF hospitalization increased significantly from $6410 in 2001 to $8439 in 2010 (24.0% increase; P<0.001). CONCLUSIONS: Hospitalization rates for AF have increased exponentially among US adults from 2000 to 2010. The proportion of comorbid chronic diseases has also increased significantly. The last decade has witnessed an overall decline in hospital mortality; however, the hospitalization cost has significantly increased.

Impact of annual operator and institutional volume on percutaneous coronary intervention outcomes: a 5-year United States experience (2005-2009).

BACKGROUND: The relationship between operator or institutional volume and outcomes among patients undergoing percutaneous coronary interventions (PCI) is unclear. METHODS AND RESULTS: Cross-sectional study based on the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample between 2005 to 2009. Subjects were identified by International Classification of Diseases, 9(th) Revision, Clinical Modification procedure code, 36.06 and 36.07. Annual operator and institutional volumes were calculated using unique identification numbers and then divided into quartiles. Three-level hierarchical multivariate mixed models were created. The primary outcome was in-hospital mortality; secondary outcome was a composite of in-hospital mortality and peri-procedural complications. A total of 457,498 PCIs were identified representing a total of 2,243,209 PCIs performed in the United States during the study period. In-hospital, all-cause mortality was 1.08%, and the overall complication rate was 7.10%. The primary and secondary outcomes of procedures performed by operators in 4(th) [annual procedural volume; primary and secondary outcomes] [>100; 0.59% and 5.51%], 3(rd) [45-100; 0.87% and 6.40%], and 2(nd) quartile [16-44; 1.15% and 7.75%] were significantly less (P<0.001) when compared with those by operators in the 1(st) quartile [≤15; 1.68% and 10.91%]. Spline analysis also showed significant operator and institutional volume outcome relationship. Similarly operators in the higher quartiles witnessed a significant reduction in length of hospital stay and cost of hospitalization (P<0.001). CONCLUSIONS: Overall in-hospital mortality after PCI was low. An increase in operator and institutional volume of PCI was found to be associated with a decrease in adverse outcomes, length of hospital stay, and cost of hospitalization.

Influence of hospital volume on outcomes of percutaneous atrial septal defect and patent foramen ovale closure: a 10-years US perspective.

BACKGROUND: Contemporary data regarding percutaneous closure of atrial septal defect/patent foramen ovale (ASD/PFO) are lacking. We evaluated the current trends in utilization of ASD/PFO closure in adults and investigated the effect of annual hospital volume on in-hospital outcomes. METHODS: We queried the Nationwide Inpatient Sample between the years 2001 and 2010 using the International Classification of Diseases (ICD-9-CM) procedure code for percutaneous closure of ASD/PFO with device. Hierarchical mixed effects models were generated to identify the independent multivariate predictors of outcomes. RESULTS: A total of 7,107 percutaneous ASD/PFO closure procedures (weighted n = 34,992) were available for analysis. A 4.7-fold increase in the utilization of this procedure from 3/million in 2001 to 14/million adults in 2010 in US (P < 0.001) was noted. Overall, percutaneous ASD/PFO closure was associated with 0.5% mortality and 12% in-hospital complications. The utilization of intracardiac echocardiography (ICE) increased 15 fold (P < 0.001) during the study period. The procedures performed at the high volume hospitals [2nd (14-37 procedures/year) and 3rd (>38 procedures/year) tertile] were associated with significant reduction in complications, length of stay and cost of hospitalization when compared to those performed at lowest volume centers (<13 procedures/year). Majority (70.5%) of the studied hospitals were found to be performing <10 procedures/year hence deviating from the ACC/AHA/SCAI clinical competency guidelines. CONCLUSIONS: Low hospital volume is associated with an increased composite (mortality and procedural complications) adverse outcome following ASD/PFO closure. In the interest of patient safety, implementation of the current guidelines for minimum required annual hospital volume to improve clinical outcomes is warranted.

In-hospital complications associated with catheter ablation of atrial fibrillation in the United States between 2000 and 2010: analysis of 93 801 procedures.

BACKGROUND: Atrial fibrillation ablation has made tremendous progress with respect to innovation, efficacy, and safety. However, limited data exist regarding the burden and trends in adverse outcomes arising from this procedure. The aim of our study was to examine the frequency of adverse events attributable to atrial fibrillation (AF) ablation and the influence of operator and hospital volume on outcomes. METHODS AND RESULTS: With the use of the Nationwide Inpatient Sample, we identified AF patients treated with catheter ablation. We investigated common complications including cardiac perforation and tamponade, pneumothorax, stroke, transient ischemic attack, vascular access complications (hemorrhage/hematoma, vascular complications requiring surgical repair, and accidental arterial puncture), and in-hospital death described with AF ablation, and we defined these complications by using validated International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes. An estimated 93,801 AF ablations were performed from 2000 to 2010. The overall frequency of complications was 6.29% with combined cardiac complications (2.54%) being the most frequent. Cardiac complications were followed by vascular complications (1.53%), respiratory complications (1.3%), and neurological complications (1.02%). The in-hospital mortality was 0.46%. Annual operator (<25 procedures) and hospital volume (<50 procedures) were significantly associated with adverse outcomes. There was a small (nonsignificant) rise in overall complication rates. CONCLUSIONS: The overall complication rate was 6.29% in patients undergoing AF ablation. There was a significant association between operator and hospital volume and adverse outcomes. This suggests a need for future research into identifying the safety measures in AF ablations and instituting appropriate interventions to improve overall AF ablation outcomes.

National Trends in Utilization, Mortality, Complications, and Cost of Care After Left Ventricular Assist Device Implantation From 2005 to 2011.

BACKGROUND: Left ventricular assist devices (LVADs) have shown survival benefit in end-stage heart failure patients. LVAD technology has evolved considerably with the development of continuous-flow devices. METHODS: The Nationwide Inpatient Sample was queried from 2005 to 2011 using International Classification of Diseases, 9th Edition procedure code 37.66, Insertion of Implantable Heart System, in any procedure field. Patients with primary diagnosis of orthotopic heart transplant or use of temporary mechanical circulatory support devices were excluded. Procedural complications were identified using International Classification of Diseases, 9th Edition codes and patient safety indicators. Cochran-Armitage and Cuzick tests for trend were used to identify time trends for categorical and continuous variables, respectively. RESULTS: There were 2,038 LVAD implantations from 2005 to 2011. LVAD use increased from 127 procedures in 2005 to 506 procedures in 2011, and in-hospital mortality declined from 47.2% to 12.7% (p < 0.001), with sharp inflection points in the year 2008. Average length of stay decreased from 44 days in the pulsatile-flow era (2005 to 2007) to 36 days in the continuous-flow era (2008 to 2011). Cost of hospitalization increased from $194,380 in 2005 to $234,808 in 2011 but remained constant from 2008 to 2011. There was a trend of increased incidence of major bleeding and thromboembolism and decreased incidence of infectious and iatrogenic cardiac complications in the continuous-flow era. CONCLUSIONS: LVAD use has increased and in-hospital mortality and LOS after LVAD implantation have declined. These changes coincide with United States Food and Drug Administration (FDA) approval of continuous-flow devices in 2008.

Vaccination Serology Status and Cardiovascular Mortality: Insight from NHANES III and Continuous NHANES.

OBJECTIVE: Prior studies have described a negative relationship between influenza vaccination and recurrence of cardiovascular (CV) events. However, due to lack of any prior studies, we evaluated and attempted to define the relationship between non-influenza vaccines and CV mortality. METHODS: We used the National Health and Nutrition Examination Survey III (NHANES III-1988-1994, n = 19,215) and Continuous NHANES (1999-2004, n > 17,000), which includes oral surveys and general examination. It was designed to assess the demographic, socioeconomic, dietary, and overall health status of a nationally representative sample in non-institutionalized patients from all 50 states in the USA. Cox proportional hazard regression modeling was used to calculate the hazard ratio of CV mortality, and multivariate models were built for the individual seropositive vaccination titers as well as after creating a combined vaccination variable. RESULTS: A total of >35,000 subjects (>18 years old) have been identified for analysis. Multivariate analysis from NHANES III and continuous NHANES did not show any influence of individual seroprotective titers of routine vaccinations on CV mortality. The combined effect of vaccination in NHANES III data did not show any protective effect of three or more positive vaccination titers (odds ratio = 0.94, p = 0.6) or all four positive vaccination titers (odds ratio = 0.93, p = 0.6) with two or less positive vaccination titers as the referent group. CONCLUSION: Effect on non-influenza vaccinations in preventing CV mortality seems to be unclear.

Impact of Hospital Volume on Outcomes of Endovascular Stenting for Adult Aortic Coarctation.

Use of transcatheter endovascular stenting has been increasing in the treatment of coarctation of aorta (CoA). The present study was undertaken on adults with CoA who underwent stent placement from 2000 to 2011 to analyze the relation of hospital volumes to the outcomes of stenting in adults with CoA. It was a retrospective study based on Healthcare Cost and Utilization Project's Nationwide Inpatient Sample (NIS) database from 2000 to 2011 and identified subjects using the International Classification of Diseases, Ninth Revision, Clinical Modification procedure code of 747.10 (CoA). 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 105 (weighted 521) subjects were identified with International Classification of Diseases, Ninth Revision, code of 39.90 (Endovascular stent). Hospital volumes were divided into tertiles. We compared the highest tertile (≥3 procedures annually) with other tertiles (<3 procedure annually). The composite outcomes of the analysis were procedure-related complications, length of stay (LOS), and cost in relation to the hospital volume. No inhospital death was reported in either group. Hospitals with ≥3 procedures annually had significantly lower incidence of complications (9.5% vs 23.0%) compared to the hospitals with <3 procedures annually (p-value 0.002). Similar results were obtained after multivariate regression analysis in relation to hospital volume. Shorter LOS and lower cost were observed with annual hospital volume of ≥3 procedures. In conclusion, stenting adults for CoA is remarkably safe, and the outcomes of the procedure have improved in centers with annual hospital volume of ≥3 procedures. There is also decreasing trend of procedure-related complications, shorter LOS, and lower costs compared to centers with annual volume <3 procedures.

Comparison of outcomes of balloon aortic valvuloplasty plus percutaneous coronary intervention versus percutaneous aortic balloon valvuloplasty alone during the same hospitalization in the United States.

The use of percutaneous aortic balloon balvotomy (PABV) in high surgical risk patients has resurged because of development of less invasive endovascular therapies. We compared outcomes of concomitant PABV and percutaneous coronary intervention (PCI) with PABV alone during same hospitalization using nation's largest hospitalization database. We identified patients and determined time trends using the International Classification of Diseases, Ninth Revision, Clinical Modification, procedure code for valvulotomy from Nationwide Inpatient Sample database 1998 to 2010. Only patients >60 years with aortic stenosis were included. Primary outcome included in-hospital mortality, and secondary outcomes included procedural complications, length of stay (LOS), and cost of hospitalization. Total 2,127 PABV procedures were identified, with 247 in PABV + PCI group and 1,880 in the PABV group. Utilization rate of concomitant PABV + PCI during same hospitalization increased by 225% from 5.1% in 1998 to 1999 to 16.6% in 2009 to 2010 (p <0.001). Overall in-hospital mortality rate and complication rates in PABV + PCI group were similar to that of PABV group (10.3% vs 10.5% and 23.4% vs 24.7%, respectively). PABV + PCI group had similar LOS but higher hospitalization cost (median [interquartile range] $30,089 [$21,925 to $48,267] versus $18,421 [$11,482 to $32,215], p <0.001) in comparison with the PABV group. Unstable condition, occurrence of any complication, and weekend admission were the main predictors of increased LOS and cost of hospital admission. Concomitant PCI and PABV during the same hospitalization are not associated with change in in-hospital mortality, complications rate, or LOS compared with PABV alone; however, it increases the cost of hospitalization.

Comparison of Inhospital Outcomes of Surgical Aortic Valve Replacement in Hospitals With and Without Availability of a Transcatheter Aortic Valve Implantation Program (from a Nationally Representative Database).

We hypothesized that the availability of a transcatheter aortic valve implantation (TAVI) program in hospitals impacts the overall management of patients with aortic valve disease and hence may also improve postprocedural outcomes of conventional surgical aortic valve replacement (SAVR). The aim of the present study was to compare the inhospital outcomes of SAVR in centers with versus without availability of a TAVI program in an unrestricted large nationwide patient population >50 years of age. SAVRs performed on patients aged >50 years were identified from the Nationwide Inpatient Sample (NIS) for the years 2011 and 2012 using the International Classification of Diseases, Ninth Revision, Clinical Modification procedure codes. SAVR cases were divided into 2 categories: those performed at hospitals with a TAVI program (SAVR-TAVI) and those without (SAVR-non-TAVI). A total of 9,674 SAVR procedures were identified: 4,526 (46.79%) in the SAVR-TAVI group and 5,148 (53.21%) in SAVR-non-TAVI group. The mean age of the study population was 70.2 ± 0.1 years with majority (53%) of the patients aged >70 years. The mean Charlson's co-morbidity score for patients in SAVR-TAVI group was greater (greater percentage of patients were aged >80 years, had hypertension, congestive heart failure, renal failure, and peripheral arterial disease) than that of patients in SAVR-non-TAVI group (1.6 vs 1.4, p <0.001). The propensity score matching analysis showed a statistically significant lower inhospital mortality (1.25% vs 1.72%, p = 0.001) and complications rate (35.6% vs 37.3%, p = 0.004) in SAVR-TAVI group compared to SAVR-non-TAVI group. The mean length of hospital stay was similar in the 2 groups the cost of hospitalization was higher in the SAVR-TAVI group ($43,894 ± 483 vs $41,032 ± 473, p <0.0001). Having a TAVI program was a significant predictor of reduced mortality and complications rate after SAVR in multivariate analysis. In conclusion, this largest direct comparative analysis demonstrates that SAVRs performed in centers with a TAVI program are associated with significantly lower mortality and complications rates compared to those performed in centers without a TAVI program.

Comparison of inhospital mortality, length of hospitalization, costs, and vascular complications of percutaneous coronary interventions guided by ultrasound versus angiography.

Despite the valuable role of intravascular ultrasound (IVUS) guidance in percutaneous coronary interventions (PCIs), its impact on clinical outcomes remains debatable. The aim of the present study was to compare the outcomes of PCIs guided by IVUS versus angiography in the contemporary era on inhospital outcomes in an unrestricted large, nationwide patient population. Data were obtained from the Nationwide Inpatient Sample from 2008 to 2011. Hierarchical mixed-effects logistic regression models were used for categorical dependent variables like inhospital mortality, and hierarchical mixed-effects linear regression models were used for continuous dependent variables like length of hospital stay and cost of hospitalization. A total of 401,571 PCIs were identified, of which 377,096 were angiography guided and 24,475 (weighted n = 119,102) used IVUS. In a multivariate model, significant predictors of higher mortality were increasing age, female gender, higher baseline co-morbidity burden, presence of acute myocardial infarction, shock, weekend and emergent admission, or occurrence of any complication during hospitalization. Significant predictors of reduced mortality were the use of IVUS guidance (odds ratio 0.65, 95% confidence interval 0.52 to 0.83; p <0.001) for PCI and higher hospital volumes (third and fourth quartiles). The use of IVUS was also associated with reduced inhospital mortality in subgroup of patients with acute myocardial infarction and/or shock and those with a higher co-morbidity burden (Charlson's co-morbidity index ≥2). In one of the largest studies on IVUS-guided PCIs in the drug-eluting stent era, we demonstrate that IVUS guidance is associated with reduced inhospital mortality, similar length of hospital stay, and increased cost of care and vascular complications compared with conventional angiography-guided PCIs.

Trends of Hospitalizations in the United States from 2000 to 2012 of Patients >60 Years With Aortic Valve Disease.

In recent years, there has been an increased emphasis on the diagnosis and treatment of valvular heart disease and, in particular, aortic stenosis. This has been driven in part by the development of innovative therapeutic options and by an aging patient population. We hypothesized an increase in the number of hospitalizations and the economic burden associated with aortic valve disease (AVD). Using Nationwide Inpatient Sample from 2000 to 2012, AVD-related hospitalizations were identified using International Classification of Diseases, Ninth Revision, Clinical Modification, code 424.1, as the principal discharge diagnosis. Overall AVD hospitalizations increased by 59% from 2000 to 2012. This increase was most significant in patients >80 years and those with higher burden of co-morbidities. The most frequent coexisting conditions were hypertension, heart failure, renal failure, anemia, and diabetes. Overall inhospital mortality of patients hospitalized for AVD was 3.8%, which significantly decreased from 4.5% in 2000 to 3.5% in 2012 (p <0.001). The largest decrease in mortality was seen in the subgroup of patients who had heart failure (62% reduction), higher burden of co-morbidities (58% reduction), and who were >80 years (53% reduction). There was a substantial increase in the cost of hospitalization in the last decade from $31,909 to $38,172 (p <0.001). The total annual cost for AVD hospitalization in the United States increased from $1.3 billion in 2001 to $2.1 billion in 2011 and is expected to increase to nearly 3 billion by 2020. The last decade has witnessed a significant increase in hospitalizations for AVD in the United States. The associated decrease in inhospital mortality and increase in the cost of hospitalization have considerably increased the economic burden on the public health system.

Effect of Hospital Volume on Outcomes of Transcatheter Aortic Valve Implantation.

Transcatheter aortic valve implantation (TAVI) is associated with a significant learning curve. There is paucity of data regarding the effect of hospital volume on outcomes after TAVI. This is a cross-sectional study based on Healthcare Cost and Utilization Project's Nationwide Inpatient Sample database of 2012. Subjects were identified by International Classification of Diseases, Ninth Revision, Clinical Modification procedure codes, 35.05 (Trans-femoral/Trans-aortic Replacement of Aortic Valve) and 35.06 (Trans-apical Replacement of Aortic Valve). Annual hospital TAVI volumes were calculated using unique identification numbers and then divided into quartiles. Multivariate logistic regression models were created. The primary outcome was inhospital mortality; secondary outcome was a composite of inhospital mortality and periprocedural complications. Length of stay (LOS) and cost of hospitalization were assessed. The study included 1,481 TAVIs (weighted n = 7,405). Overall inhospital mortality rate was 5.1%, postprocedural complication rate was 43.4%, median LOS was 6 days, and median cost of hospitalization was $51,975. Inhospital mortality rates decreased with increasing hospital TAVI volume with a rate of 6.4% for lowest volume hospitals (first quartile), 5.9% (second quartile), 5.2% (third quartile), and 2.8% for the highest volume TAVI hospitals (fourth quartile). Complication rates were significantly higher in hospitals with the lowest volume quartile (48.5%) compared to hospitals in the second (44.2%), third (39.7%), and fourth (41.5%) quartiles (p <0.001). Increasing hospital volume was independently predictive of shorter LOS and lower hospitalization costs. In conclusion, higher annual hospital volumes are significantly predictive of reduced postprocedural mortality, complications, shorter LOS, and lower hospitalization costs after TAVI.

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.

Comparison of Inhospital Outcomes and Hospitalization Costs of Peripheral Angioplasty and Endovascular Stenting.

The comparative data for angioplasty and stenting for treatment of peripheral arterial disease are largely limited to technical factors such as patency rates with sparse data on clinical outcomes like mortality, postprocedural complications, and amputation. The study cohort was derived from the Healthcare Cost and Utilization Project Nationwide Inpatient Sample database from 2006 to 2011. Peripheral endovascular interventions were identified using appropriate International Classification of Diseases, Ninth Revision (ICD-9) Diagnostic and procedural codes. Two-level hierarchical multivariate mixed models were created. The primary outcome includes inhospital mortality, and secondary outcome was a composite of inhospital mortality and postprocedural complications. Amputation was a separate outcome. Hospitalization costs were also assessed. Endovascular stenting (odds ratio, 95% confidence interval, p value) was independently predictive of lower composite end point of inhospital mortality and postprocedural complications compared with angioplasty alone (0.96, 0.91 to 0.99, 0.025) and lower amputation rates (0.56, 0.53 to 0.60, <0.001) with no significant difference in terms of inhospital mortality alone. Multivariate analysis also revealed stenting to be predictive of higher hospitalization costs ($1,516, 95% confidence interval 1,082 to 1,950, p <0.001) compared with angioplasty. In conclusion, endovascular stenting is associated with a lower rate of postprocedural complications, lower amputation rates, and only minimal increase in hospitalization costs compared with angioplasty alone.

Optimal blood pressure in patients with atrial fibrillation (from the AFFIRM Trial).

Many medications used to treat atrial fibrillation (AF) also reduce blood pressure (BP). The relation between BP and mortality is unclear in patients with AF. We performed a post hoc analysis of 3,947 participants from the Atrial Fibrillation Follow-Up Investigation of Rhythm Management trial. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) at baseline and follow-up were categorized by 10-mm Hg increments. The end points were all-cause mortality (ACM) and secondary outcome (combination of ACM, ventricular tachycardia and/or fibrillation, pulseless electrical activity, significant bradycardia, stroke, major bleeding, myocardial infarction, and pulmonary embolism). SBP and DBP followed a "U-shaped" curve with respect to primary and secondary outcomes after multivariate analysis. A nonlinear Cox proportional hazards model showed that the incidence of ACM was lowest at 140/78 mm Hg. Subgroup analyses revealed similar U-shaped curves. There was an increased ACM observed with BP <110/60 mm Hg (hazard ratio 2.4, p <0.01, respectively, for SBP and DBP). In conclusion, in patients with AF, U-shaped relation existed between BP and ACM. These data suggest that the optimal BP target in patients with AF may be greater than the general population and that pharmacologic therapy to treat AF may be associated with ACM or adverse events if BP is reduced to <110/60 mm Hg.