Frequency of in-hospital adverse outcomes and cost utilization associated with cardiac resynchronization therapy defibrillator implantation in the United States.

BACKGROUND: The utilization of cardiac resynchronization therapy defibrillator (CRT-D) has increased significantly, since its initial approval for use in selected patients with heart failure. Limited data exist as for current trends in implant-related in-hospital complications and cost utilization. The aim of our study was to examine in-hospital complication rates associated with CRT-D and their trends over the last decade. METHODS AND RESULTS: Using the Nationwide Inpatient Sample, we estimated 378 248 CRT-D procedures from 2003 to 2012. We investigated common complications, including mechanical, cardiovascular, pericardial complications (hemopericardium, cardiac tamponade, or pericardiocentesis), pneumothorax, stroke, vascular complications (consisting of hemorrhage/hematoma, incidents requiring surgical repair, and accidental arterial puncture), and in-hospital deaths described with CRT-D, defining them by the validated International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code. Mechanical complications (5.9%) were the commonest, followed by cardiovascular (3.6%), respiratory failure (2.4%), and pneumothorax (1.5%). Age (≥65 years), female gender (OR, 95% CI; P value) (1.08, 1.03-1.13; 0.001), and the Charlson score ≥3 (1.52, 1.45-1.60; <0.001) were significantly associated with increased mortality/complications. CONCLUSIONS: The overall complication rate in patients undergoing CRT-D has been increasing in the last decade. Age (≥65), female sex, and the Charlson score ≥3 were associated with higher complications. In patients who underwent CRT-D implantation, postoperative complications were associated with significant increases in cost.

Transcatheter aortic valve replacement versus surgical aortic valve replacement in patients with cirrhosis.

OBJECTIVES: To compare the in-hospital outcomes in cirrhosis patients undergoing transcatheter aortic valve replacement (TAVR) versus those undergoing surgical aortic valve replacement (SAVR). BACKGROUND: Over the last 10 years, TAVR has emerged as a therapeutic option for treating severe aortic stenosis in high-risk patients. Cirrhosis patients have a high risk of operative morbidity and mortality while undergoing cardiac surgery. This study's hypothesis was that TAVR is a safer alternative compared to SAVR in cirrhosis patients. METHODS: The study population was derived from the National Inpatient Sample (NIS) for the years 2011-2012 using ICD-9-CM procedure codes 35.21 and 35.22 for SAVR, and 35.05 and 35.06 for TAVR. Patients <50 years of age and those who concomitantly underwent other valvular procedures were excluded. ICD-9-CM diagnosis codes were used to identify patients with liver cirrhosis, portal hypertension, and esophageal varices. Using propensity score matching, two matched cohorts were derived in which the outcomes were compared using appropriate statistical tests. RESULTS: There were 30 patients in the SAVR and TAVR group each. Compared to the TAVR group, the patients in SAVR group had significantly higher rate of transfusion of whole blood or blood products (p = 0.037), longer mean postprocedural length of stay (p = 0.006), and nonsignificantly higher mean cost of hospitalization (p = 0.2), any complications rate (p = 0.09), and liver complications rate (p = 0.4). In-hospital mortality rate was same in the both the groups. No patients in the TAVR group required open-heart surgery or cardiopulmonary bypass. CONCLUSION: TAVR could be a viable option for aortic valve replacement in cirrhosis patients.

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.

Intravascular Ultrasound in Lower Extremity Peripheral Vascular Interventions: Variation in Utilization and Impact on In-Hospital Outcomes From the Nationwide Inpatient Sample (2006-2011).

PURPOSE: To examine the impact of intravascular ultrasound (IVUS) utilization during lower limb endovascular interventions as regards postprocedural complications and amputation. METHODS: The study cohort was derived from the Healthcare Cost and Utilization Project Nationwide Inpatient Sample database between the years 2006 and 2011. Peripheral endovascular interventions were identified using appropriate ICD-9 procedure codes. Two-level hierarchical multivariate mixed models were created. The co-primary outcomes were in-hospital mortality and amputation; the secondary outcome was postprocedural complications. Model results are given as the odds ratio (OR) and 95% confidence interval (CI). Hospitalization costs were also assessed. RESULTS: Overall, among the 92,714 patients extracted from the database during the observation period, IVUS was used in 1299 (1.4%) patients. IVUS utilization during lower extremity peripheral vascular procedures was independently predictive of a lower rate of postprocedural complications (OR 0.80, 95% CI 0.66 to 0.99, p=0.037) as well as lower amputation rates (OR 0.59, 95% CI 0.45 to 0.77, p<0.001) without any significant impact on in-hospital mortality. Multivariate analysis also revealed IVUS utilization to be predictive of a nonsignificant increase in hospitalization costs ($1333, 95% CI -$167 to +$2833, p=0.082). CONCLUSION: IVUS use during lower limb endovascular interventions is predictive of lower postprocedural complication and amputation rates with a nonsignificant increase in hospitalization costs.

Percutaneous Coronary Intervention: Relationship Between Procedural Volume and Outcomes.

Percutaneous coronary intervention (PCI) is an integral treatment modality for acute coronary syndromes (ACS) as well as chronic stable coronary artery disease (CAD) not responsive to optimal medical therapy. This coupled with studies on the feasibility and safety of performing PCI in centers without on-site surgical backup led to widespread growth of PCI centers. However, this has been accompanied by a recent steep decline in the volume of PCIs at both the operator and hospital level, which raises concerns regarding minimal procedural volumes required to maintain necessary skills and favorable clinical outcomes. The 2011 ACC/AHA/SCAI competency statement required PCI be performed by operators with a minimal procedural volume of >75 PCIs annually at high-volume centers with >400 PCIs per year, a number which was relaxed in the 2013 ACC/AHA/SCAI update to >50 PCIs/operator/year in hospitals with >200 PCIs annually to coincide with reduction in national PCI volume. Recent data suggests that many hospitals do not meet these thresholds. We review data on the importance of volume as a vital quality metric at both an operator and hospital level in determining procedural outcomes following PCI.

Influence of same-day admission on outcomes following transcatheter aortic valve replacement.

BACKGROUND: Since elective transcatheter aortic valve replacements (TAVRs) can be performed on the day of admission, i.e., Day 0, or on the next day of admission, i.e., Day 1, we sought to investigate if there is an advantage to either approach. METHODS: We performed a retrospective cohort study, using the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample database of 2012 and identified subjects undergoing endovascular (Transfemoral/Transaortic) TAVRs using the ICD-9-CM procedure code of 35.05. The cohort was divided based on the day of the TAVR performed, i.e., Day 0 or 1. The cost of the hospitalization and length of stay were the primary outcomes, with in-hospital mortality and procedural complications as the secondary outcomes. We identified a total of 843 TAVRs. Propensity matched models were created. The mean age of the study cohort was 82 years. RESULTS: In a propensity-matched dataset, TAVRs performed on Day 0 were associated with a lower cost ($51,126 ± 1184 vs $57,703 ± 1508, p < 0.0001) and length of stay (mean days, standard error: 5.87 ± 0.25 vs 7.20 ± 0.29, p < 0.001) compared to Day 1. In-hospital mortality plus complication rates were relatively similar with no difference between Days 0 and 1 (31.5% vs 34.1%, p = 0.47, respectively). CONCLUSIONS: Endovascular TAVRs performed on the same day of admission are associated with lower hospitalization costs and length of stay, and similar mortality and complication rates compared to those performed on the next day of admission.

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.

Utilization of catheter-directed thrombolysis in pulmonary embolism and outcome difference between systemic thrombolysis and catheter-directed thrombolysis.

OBJECTIVE: The aim of the study was to assess the utilization of catheter-directed thrombolysis (CDT) and its comparative effectiveness against systemic thrombolysis in acute pulmonary embolism (PE). BACKGROUND: Contemporary real world data regarding utilization and outcomes comparing systemic thrombolysis with CDT for PE is sparse. METHODS: We queried the Nationwide Inpatient Sample from 2010 to 2012 using the ICD-9-CM diagnosis code 415.11, 415.13, and 415.19 for acute PE. We used propensity score analysis to compare outcomes between systemic thrombolysis and CDT. Primary outcome was in-hospital mortality. Secondary outcome was combined in-hospital mortality and intracranial hemorrhage (ICH). RESULTS: Out of 110,731 patients hospitalized with PE, we identified 1,521 patients treated with thrombolysis, of which 1,169 patients received systemic thrombolysis and 352 patients received CDT. After propensity-matched comparison, primary and secondary outcomes were significantly lower in the CDT group compared to systemic thrombolysis (21.81% vs. 13.36%, OR 0.55, 95% CI 0.36-0.85, P value = 0.007) and (22.89% vs. 13.36%, OR 0.52, 95% CI 0.34-0.80, P value = 0.003), respectively. The median length of stay [7 days, interquartile range (IQR) (5-9 days) vs. 7 days, IQR (5-10 days), P = 0.17] was not significant between the two groups. The CDT group had higher cost of hospitalization [$17,218, IQR ($12,272-$23,906) vs. $23,799, IQR ($17,892-$35,338), P < 0.001]. Multivariate analysis identified increasing age, saddle PE, cardiopulmonary arrest, and Medicaid insurance as independent predictors of in-hospital mortality. CONCLUSIONS: CDT was associated with lower in-hospital mortality and combined in-hospital mortality and ICH.

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.

Percutaneous Coronary Interventions and Hemodynamic Support in the USA: A 5 Year Experience.

OBJECTIVES: To compare the utilization and outcomes in patients who had percutaneous coronary interventions (PCIs) performed with intra-aortic balloon pump (IABP) versus percutaneous ventricular assist devices (PVADs) such as Impella and TandemHeart and identify a sub-group of patient population who may derive the most benefit from the use of PVADs over IABP. BACKGROUND: Despite the lack of clear benefit, the use of PVADs has increased substantially in the last decade when compared to IABP. METHODS: We performed a cross sectional study including using the Nationwide Inpatient Sample. Procedures performed with hemodynamic support were identified through appropriate ICD-9-CM codes. RESULTS: We identified 18,094 PCIs performed with hemodynamic support. IABP was the most commonly utilized hemodynamic support device (93%, n = 16, 803) whereas 6% (n = 1069) were performed with PVADs and 1% (n = 222) utilized both IABP and PVAD. Patients in the PVAD group were older in age and had greater burden of co-morbidities whereas IABP group had higher percentage of patients with cardiac arrest. On multivariable analysis, the use of PVAD was a significant predictor of reduced mortality (OR 0.55, 0.36-0.83, P = 0.004). This was particularly evident in sub-group of patients without acute MI or cardiogenic shock. The propensity score matched analysis also showed a significantly lower mortality (9.9% vs 15.1%; OR 0.62, 0.55-0.71, P < 0.001) rate associated with PVADs when compared to IABP. CONCLUSION: This largest and the most contemporary study on the use of hemodynamic support demonstrates significantly reduced mortality with PVADs when compared to IABP in patients undergoing PCI. The results are largely driven by the improved outcomes in non-AMI and non-cardiogenic shock patients.

Effect of Hospital Volume on Outcomes of Transcatheter Mitral Valve Repair: An Early US Experience.

BACKGROUND: Transcatheter mitral valve repair (TMVR) is a complex procedure for patients with mitral regurgitation who cannot get surgery. However, there is a lack of data on how hospital volumes affect these outcomes. METHODS: We performed a cross sectional study based on Healthcare Cost and Utilization Project's Nationwide Inpatient Sample database of 2012 and identified subjects using the ICD-9-CM procedure code of 35.97, which was introduced in October 2010 for percutaneous mitral valve repair if present in the primary or secondary procedure field. Hospital volumes were divided into tertiles. The primary outcome was a composite of in-hospital mortality and peri-procedural complications. Length of stay and hospitalization cost were also assessed. RESULTS: A total of 95 (weighted n = 475) TMVR procedures were identified. The mean age of the overall cohort was 70 years; 43.2% were female and 63.2% had a significant baseline burden of co-morbidities. The composite of in-hospital mortality and peri-procedural complications decreased with increasing TMVR hospital volume: 48.7% in the first tertile, 17.4% in the second tertile, and 9.1% in the third tertile. Additionally, we saw a decrease in the length of stay and a trend in decrease in the hospitalization cost. CONCLUSION: In hospitals performing TMVR, higher hospital volumes are associated with a reduction in a composite of in-hospital mortality and post-procedural complications, in addition to the shorter length of stay.

Complications and Mortality in Patients Undergoing Transcatheter Aortic Valve Replacement With Edwards SAPIEN & SAPIEN XT Valves: A Meta-Analysis of World-Wide Studies and Registries Comparing the Transapical and Transfemoral Accesses.

INTRODUCTION: Both transfemoral (TF) and transapical (TA) routes are utilized for Transcatheter Aortic Valve Replacement (TAVR) using Edwards SAPIEN & SAPIEN XT valves. We intended to perform a meta-analysis comparing the complication rates between these two approaches in studies published before and after the standardized Valve Academic Research Consortium (VARC) definitions. METHODS: We performed a comprehensive electronic database search for studies published until January 2014 comparing TF and TA approaches using the Edwards SAPIEN/SAPIEN XT aortic valve. Studies were analyzed based on the following endpoints: 1-year mortality, 30-day mortality, stroke, new pacemaker implantation, bleeding, and acute kidney injury. RESULTS: Seventeen studies were included in the meta-analysis. Patients undergoing TA TAVR had a significantly higher logistic EuroSCORE (24.6 ± 12.9 vs. 21.3 ± 12.0; P < 0.001). The cumulative risks for 30-day mortality (RR 0.61; 95%CI 0.46-0.81; P = 0.001), 1-year mortality (RR 0.68; 95%CI 0.55-0.84; P < 0.001), and acute kidney injury (RR 0.53; 95%CI 0.38-0.73; P < 0.001) were significantly lower for patients undergoing TF as compared to TA approach. Both approaches had a similar incidence of 30-day stroke, pacemaker implantation, and major or life-threatening bleeding. Studies utilizing the VARC definitions and those pre-dating VARC yielded similar results. CONCLUSION: This meta-analysis demonstrates a decreased 30-day and 1-year mortality in TF TAVR as compared to TA TAVR. Post-procedure acute kidney injury and the need for renal replacement therapy are also significantly lower in the TF group. These differences hold true even after utilizing the standardized Valve Academic Research Consortium criteria.

Radionuclide cardiac stress testing.

PURPOSE OF REVIEW: To briefly review the field of radionuclide stress imaging, including recent technologic advances and clinical applications. RECENT FINDINGS: ECG gating and attenuation correction help increase specificity and accuracy of myocardial single-photon emission computed tomography (SPECT) imaging. Furthermore, advances in camera hardware and software enable more rapid image acquisition and/or radiation dose reduction. Position emission tomography (PET) and hybrid imaging with computer tomography (CT) are emerging technologies which provide improved image resolution and complementary anatomical data. Nuclear cardiology also demonstrates a wide variety of prognostic applications for a diverse group of patient subgroups. More judicious use of SPECT technology using application of the recently updated appropriateness criteria is encouraged. SUMMARY: Radionuclide stress imaging provides essential clinical information and has clear impact on patient assessment and management.

Pharmacotherapy of atrial fibrillation: a pathophysiological perspective and review.

Atrial fibrillation (AF) is one of the most common arrhythmia encountered in clinical practice. Although AF is due to the structural and electrophysiological alterations in the atria, its sustainability is multifactorial, and the actual mechanisms are still not clear. Despite the recent advances in catheter ablation technology and techniques, pharmacotherapy still remains the first-line therapy for the management of AF. Current pharmacotherapy targets ion channel alterations that in fact represent only one aspect of the management of this complex arrhythmia. Successful pharmacological treatment of AF and restoration of sinus rhythm is limited and is in part due to its potential deleterious side effects. Newer agents having diverse mechanisms acting on the recently uncovered pathophysiological processes are on the horizon. These include atrial repolarization delaying agents, newer class III agents, Na(+)-Ca(2+) channel blockers, stretch receptor blockers, I(KACH) blockers, gap junction modifiers, upstream therapies, and agents targeting ischemia-induced AF. Gene- and cell-specific therapies including 'tailored nanopharmacy,' newer rate control medications with minimal side effects and the emergence of novel drugs targeting multiple areas of AF arrhythmogenesis in tandem with electrical therapy may be the future direction in the management of AF.

Preserved or slightly depressed ejection fraction and outcomes after myocardial infarction.

BACKGROUND Left ventricular ejection fraction (EF) in post-myocardial infarction (MI) patients is a strong predictor of adverse cardiovascular events. Although resting EF as measured by transthoracic echocardiography (TTE), contrast ventriculography (CNV), and radionuclide angiography (RNA) exhibit high correlation, there is only modest agreement between these modalities. This study sought to explore whether modality of EF assessment influences prognostication of post-MI patients with normal or slightly reduced EF. METHODS AND RESULTS The National Heart, Lung, and Blood Institute (NHLBI) limited access dataset of the Prevention of Events with Angiotensin Converting Enzyme Inhibition (PEACE) Trial (1996-2003, n=8290) comparing trandolapril versus placebo was used. The cohort was partitioned into TTE (n=2582), RNA (n=816), and CNV (n=1155) groups based on modality of EF assessment. EF was a significant predictor of cardiovascular mortality (HR 0.97, 95% CI 0.95 to 0.98; p<0.005) and all cause mortality (HR 0.98, 95% CI 0.97 to 0.99; p=0.0002) on multivariate analysis in this population with preserved or mildly depressed EF. Although CNV, TTE, and RNA groups differed significantly in terms of baseline variables, no appreciable differences were noted between RNA (HR 1.13, 95% CI 0.85 to 1.50; ns) and CNV (HR 1.13, 95% CI 0.99 to 1.27; ns) groups, compared with TTE for all cause mortality. Similarly, no significant differences were observed for cardiovascular mortality between RNA (HR 1.23, 95% CI 0.82 to 1.84; p=0.31) and CNV (HR 1.14, 95% CI 0.78 to 1.67, p=0.49) versus TTE. CONCLUSION EF is a significant predictor of all-cause mortality and cardiovascular mortality in patients with preserved or mildly depressed EF. Modalities of EF measurement are interchangeable and do not play a significant role in prognostication in a post-MI population.