Kumar, Varun

Introduction: Takotsubo cardiomyopathy (TTC) is diagnosed in 1-2% of the patients presenting with troponin positive suspected acute coronary syndromes(ACS). Rising trends of adverse events in patients with TTC, makes it imperative to explore causes and predictors of readmission in this patient population. Methods: National Readmission Data (NRD) 2013-14 was utilized to select study cohort. International Classification of Diseases, 9th Revision (ICD-9-CM) diagnostic code 429.83 was used to identify takotsubo cardiomyopathy. Admissions within 90 day of index admission were considered as early readmissions. Readmission etiologies were identified by ICD-9-CM code in primary diagnosis field of readmissions. Hierarchical multivariate models were used to evaluate predictors of early readmission. Results: A total of 12255 patients were identified during study period out of which 23.92% (n=2932 with 4224 readmissions) patients were readmitted within 90 days of discharge following index admission. Most common etiologies for readmission were cardiac (18.56%), respiratory (17.20%), GI renal (9.10%), infections (13.12%) and neurological complications (5.88%). Among cardiac complications acute heart failure was the most common etiology (7.48%). Highest number of readmissions happened on first day after discharge (n=125) and within 33 days after discharge, >50% of readmissions took place (n=2136). Conclusions: Patients with TTC are highly likely to be readmitted with first month after discharge, most likely secondary to cardiac or respiratory complications. These findings warrant close post discharge transition to reduce morbidity and improve health care outcomes.

Introduction: Catheter ablation is widely accepted intervention for atrial fibrillation (AF), but data is limited on contemporary trends in major complications and mortality due to the procedure. Methods: HCUP’s Nationwide inpatient sample (NIS) database was utilized from 2011-14 to identify the AF patients treated with Catheter Ablation using ICD-9- CM codes. χ 2 test was utilized to compare categorical variables, the student’s t-test for continuous variables and hierarchical mixed-effects logistic regression models for multivariate predictors of post-procedural complications. Results: In total 50,969 patients were identified undergoing AF ablation during the study period (37.6% female, 51.4 age ≥ 65). Overall complication rate was 5.5% with relative increase over study period (+56.4%, p < 0.001). In subgroup analysis of complication trends significant relative increase seen in respiratory (+352.7%, p < 0.001), neurological (+43.9%, p = 0.003) and vascular (+38.7%, p = 0.003) complications. While cardiac complications (+9.1%, p = 0.323) and In-hospital mortality (+ 60%, p = 0.173) showed insignificant change. On multivariate analysis of mortality and complication significant increased risk was associated with female gender (OR, 95% CI, p-value) (1.40, 1.17-1.68, p < 0.001), as well as higher comorbidity burden (CCI ≥ 1). While higher hospital volume (≥ 50 procedures) was associated with significantly decreased complication rates. Conclusions: Patients undergoing AF ablation showed an insignificant change in mortality, with increase trends of complication. Which was likely related to higher comorbidity burden over study period.

Introduction: Heart failure with preserved ejection fraction(HFpEF) is a syndromemwith limited treatment modalities. Our control over 30 day readmissions and readmission outcomes is limited. Methods: HCUP’s Nationwide Readmissions Database (NRD) from 2013-14 was used for HFpEF related hospitalizations using ICD-9- CM diagnostic code:428.3x in primary diagnosis field. 30-day readmissions were identified and classified into two groups: same-hospital readmissions and different-hospital readmissions. A comparative analysis was conducted focused on three metrics - mortality, length of stay (LOS) and cost of hospitalization. We used hierarchical two-level modeling and propensity score matching to adjust for confounders. Results: Of the 94,988 readmitted patients (age &gt;65 years: 79%, Females: 61.45%) - 76,665 (80.70%) to the same hospital and rest to different hospitals. After adjusting extensive list of confounders, same hospital readmission was associated with better outcomes including in hospital mortality (OR: 0.73, 95% CI: 0.66 - 0.80, p&lt;0.001), LOS (Days: -1.14, 95% CI: -1.31 - -0.97, p&lt;0.001), Cost of care ($: -4208, 95% CI: - 4681 - -3734, p&lt;0.001). For validation of our results, we ran propensity score matching, showed similar results - in hospital mortality (6.23% vs 8.07%), LOS (6.30 ± 0.08 vs 7.47 ± 0.095), Cost of care (14042.7 ± 215.7 vs 18685.4 ± 279.2). Post hoc high-risk subgroup analysis were conducted and showed similar results (Figure). Number needed to treat (for mortality) was 74 patients. Up to ~ 100 million dollars could have been saved over 2 years. Conclusions: Considering scale of problem and limited option to prevent worse outcomes, Simple interventions such as redirecting patient to same hospital as previous admission would be beneficial.

Introduction: Role of therapeutic hypothermia in out of hospital cardiac arrest is well studied but data is sparse for in-hospital cardiac arrest (IHCA). Methods: Nationwide Inpatient Sample (NIS) database from 2011-2014 was utilized to identify ICHA using the ICD-9-CM procedural codes 99.60(CPR) and 99.63(closed cardiac massage) in any procedural fields. Therapeutic hypothermia was identified by 99.81 in any procedural field. Patient with age<18 years and missing information on age, gender and mortality was removed. Primary outcome was hospitalization survival. We used Greedy’s algorithm for propensity score match (1:20) to adjust for extensive list of clinically important confounders. We used simple logistic regression to generate odds ratio on matched cohort. Results: 86,593 patients (Age>65 years: 58.48%, female: 44.12%) with In hospital cardiac arrest was identified,of which 1777 (2.05 %) received therapeutic hypothermia. Overall survival was 30%- with or without hypothermia. After propensity score matching (1:20) we identified 1537 matched pairs (32,277 patients) without any statically significant difference in baseline characteristics between two groups. C- index for the model was 0.714. Worse survival was observed in patients with hypothermia in matched cohort [Survival: (31.82% without hypothermia vs. 28.1% with hypothermia with p-value- 0.002) (OR:0.84, 95% CI:0.75-0.94, p-0.002)]. About a quarter of in-hospital cardiac arrest were Vfib/Vtach arrest and Subgroup propensity score match analysis in Vfib/Vtach arrest showed better survival without hypothermia, similar results were observed in PEA/asystole cardiac arrest. Conclusion: Worst survival was observed with hypothermia in hospital cardiac arrest patients. Risk of hypothermia complications outweighs the benefit of preserving brain in patients who received almost immediate resuscitation. Future clinical trials and prospective studies will be needed to concur our results.

Introduction: Risk stratification of the pregnant population is critical to improving outcomes associated with pregnancy-related Acute myocardial infarction (AMI). Methods: Pregnancy-related hospitalizations (antepartum as well as postpartum) and AMI were identified using appropriate International classification of disease-Ninth revision (ICD-9) codes from nationwide inpatient sample database (2005-2014). Simple logistic regression was used to calculate predictors of AMI during pregnancy. Results: We identified 3,786 cases of AMI from a total of 43,437,621 pregnancy related hospitalization during study period. Compared to pregnant women <20-year, we noted more than 10-fold risk of AMI among patients ≥ 40 years (OR 10.1, 95% CI 5.3-19.0, p<0.001). Other significant predictors of AMI during pregnancy were black race compared to white ( OR 1.6, 95% CI 1.3-1.9, p<0.001), co-existing comorbidities such as hypertension (OR 1.9, 95% CI 1.5-2.5, p<0.001),, thrombophilia (OR 4.8, 95% CI 2.7-8.5, p<0.001), diabetes milletus (OR 1.4, 95% CI 1.0-1.9, p<0.027),hyperlipidemia (OR 13.2, 95% CI 9.9-17.6, p<0.001),smoking (OR 3.3, 95% CI 2.3-4.6, p<0.001), substance abuse (OR 1.7, 95% CI 1.2-2.6, p=0.007), congestive heart failure (OR 26.0, 95% CI 20.3-33.2 p<0.001), deep venous thrombosis (OR 2.8, 95% CI 1.3-6.2, p=0.010) as well as obstetric condition including postpartum hemorrhage (OR 1.8, 95% CI 1.3-2.4, p<0.001),, transfusion during pregnancy (OR 3.2, 95% CI 2.4-4.2, p<0.001), postpartum infection (OR 2,7, 95% CI 1.9-3.9, p<0.001),, fluid and electrolyte imbalance (OR 5.2, 95% CI 4.2- 6.6, p<0.001), and postpartum depression (OR 1.4, 95% CI 1.1-1.9 p=0.013). Conclusions: We identified certain patient-level characteristics which correlated to high risk of AMI. This information can be utilized to decide resource allocation and the introduction of early multidisciplinary intervention among high-risk population

Introduction: Acute myocardial infarction (AMI) during pregnancy is a rare but fatal complication. Recent trends in incidence of pregnancy-related AMI and associated outcomes are unclear. Methods: Nationwide inpatient sample (NIS) database was utilized for years 2005-2014. International classification of disease-Ninth revision (ICD-9) was used to identify pregnancy-related (antepartum as well as postpartum) admissions and acute myocardial infarction (AMI). The primary outcome was incidence and trend of AMI related to pregnancy during the study period. Secondary outcomes were trends in mortality and resource utilization. P-values for trends were generated by Cochrane-Armitage test for categorical variables and simple linear regression for continuous variables. Results: We identified a total of 43,437,621 pregnancy-related hospitalization and 3,786 cases of AMI (86% antepartum and 14% post-partum) were noted during the study period. The incidence of AMI during the study period was 8.7 per 100,000 pregnancies with an overall increase in incidence during study period (relative increase of 18.9%, p <0.001) and concomitant decrease in mortality (relative decrease of 40.05%, p <0.001), cost of care (relative decrease of 8.70%, p<0.001) and length of stay (relative decrease of 13.53%, p<0.001). Conclusions: Incidence of AMI during the period is on the rise in recent years with concomitant improvement in mortality and resource utilization. This reflects improved diagnostic capability and a better understanding of non-atherosclerotic mechanisms of AMI during pregnancy such as spontaneous coronary artery dissection, coronary spasm, and coronary thrombus.

Introduction: Recent trials have suggested potential benefits of performing multivessel percutaneous coronary intervention (MVPCI) on non-infarct related artery (non-IRA) in ST-segment elevation myocardial infarction (STEMI) patients with multivessel disease. Methods: National Readmissions Database (NRD) 2010-14 was utilized to select study cohort. Appropriate International Classification of Diseases, 9th Revision (ICD-9-CM) diagnostic and procedural codes were utilized to identify STEMI patients undergoing multivessel PCI and infarct-related artery only PCI (IRA-PCI). Propensity score matched cohorts using greedy matching algorithm were generated for comparison of outcomes. Results: We identified 116592 IRA-PCI (83.97%) and 22257 MVPCI (16.03%) cases. With 1:3 propensity matched cohorts accounting for confounders such as age, gender, race and comorbidities, in comparison to IRA-PCI, MVPCI patients have higher 30-day readmission rate (10.40% vs 9.40%, p=0.001), in-hospital mortality (1.96% vs 1.57%,p<0.001), mechanical circulatory support utilization (4.27 vs 2.44%,p<0.001) as well as higher complication including vascular (0.51% vs 0.28%, p<0.001), cardiac (5.97% vs 3.97%, p<0.001), respiratory (4.89% vs 4.02%,p<0.001), neurologic complications (0.77% vs 0.58%,p=0.003), major bleeding (1.01% vs 0.79%, p=0.002) and cardiac arrest(3.48% vs 3.17%, p=0.027). We also noted higher cost of care ($27100 vs $20900, p<0.001) and length of stay (3.8 days vs 3.4 days, p<0.001) in MVPCI group compared to IRA-PCI group. Conclusions: We noted higher 30- day readmission rate, in-hospital mortality, complications and resource utilization with MVPCI compared to IRA-PCI approach among STEMI patients which further demands large-scale randomized control trials to determine the utility of MVPCI in the “real world”.

AbstractBackgroundUtilization of catheter ablation of ventricular tachycardia (VT) has steadily increased in recent years. Exploring short‐term outcomes is vital in health care planning and resource allocation.MethodsThe Nationwide Readmissions Database from 2010 to 2014 was queried using the ICD‐9 codes for VT (427.1) and catheter ablation (37.34) to identify study population. Incidence, causes of 30‐day readmission, in‐hospital complications as well as predictors of 30‐day readmissions, complications, and cost of care were analyzed.ResultsAmong 11 725 patients who survived to discharge after index admission for VT ablation, 1911 (16.3%) were readmitted within 30 days. Paroxysmal VT was the most common cause of 30‐day readmission (39.51%). Dyslipidemia, chronic kidney disease (CKD), previous CABG, congestive heart failure (CHF), chronic pulmonary disease, and anemia predicted increased risk of 30‐day readmissions. The overall in‐hospital complication rate was 8.2% with vascular and cardiac complications being the most common. Co‐existing CKD and CHF and the need for mechanical circulatory support (MCS) predicted higher complication rates. Similarly increasing age, CKD, CHF, anemia, in‐hospital use of MCS or left heart catheterization, teaching hospital, and disposition to nursing facilities predicted higher cost.ConclusionApproximately one in six patients was readmitted after VT ablation, with paroxysmal VT being the most common cause of the readmission. A complication rate of 8.2% was noted. We also identified a predictive model for increased risk of readmission, complication, and factors influencing the cost of care that can be utilized to improve the outcomes related to VT ablation.

Background Atrial fibrillation is the most common arrhythmia worldwide. Data regarding 30‐day readmission rates after discharge for atrial fibrillation remain poorly reported. Methods and Results The Nationwide Readmission Database (2010–2014) was queried using the International Classification of Diseases, Ninth Revision ( ICD‐9 ) codes to identify study population. Incidence, etiologies of 30‐day readmission and predictors of 30‐day readmissions, and cost of care were analyzed. Among 1 723 378 patients who survived to discharge, 249 343 (14.4%) patients were readmitted within 30 days. Compared with the readmitted group, the nonreadmitted group had higher utilization of electrical cardioversion and catheter ablation. Atrial fibrillation was the most common cause of readmission (24.1%). Median time to 30‐day readmission was 13 days. Advancing age, female sex, and longer stay during index hospitalization predicted higher 30‐day readmissions, whereas private insurance, electrical cardioversion, catheter ablation, higher income, and elective admissions correlated with lower 30‐day readmission. Comorbidities such as heart failure, neurological disorder, chronic obstructive pulmonary disease, diabetes mellitus, chronic kidney disease, chronic liver failure, coagulopathy, anemia, peripheral vascular disease, and electrolyte disturbance, correlated with increased 30‐day readmissions and cost burden. Trend analysis showed a progressive decline in 30‐day readmission rates from 14.7% in 2010 to 14.3% in 2014 ( P trend, <0.001). Conclusions Approximately 1 in 7 patients were readmitted within 30 days of discharge, with symptomatic atrial fibrillation being the most common cause. We identified a predictive model for increased risk of readmissions and treatment expense. Electrical cardioversion during index admission was associated with a significant reduction in 30‐day readmissions and service charges. The 30‐day readmissions correlated with a substantial rise in the cost of care.

AbstractBackgroundHypertrophic cardiomyopathy (HCM) accounts for significant morbidity and mortality worldwide. Arrhythmias are considered the main cause of mortality, however, there is paucity of data relating to trends of arrhythmia and associated outcomes in HCM patients.MethodsNationwide Inpatient Sample from 2003 to 2014 was analyzed. HCM related hospitalizations were identified using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD9‐CM) code 425.1 and 425.11 in all diagnosis fields.ResultsOverall, there was an increase in number of hospitalizations related to arrhythmias among HCM patients from 7784 in 2003 to 8380 in 2014 (relative increase 10.5%, P < 0.001). The increase was most significant in patients ≥ 80 years and those with higher comorbidity burden. Atrial fibrillation (AF) was the most frequently occurring arrhythmia however atrial flutter (AFL) witnessed the highest rise during the study period. In general, there was a down trend in mortality with the greatest reduction occurring in patients with ventricular fibrillation/flutter (VF/VFL). The mean length of stay was higher if patients had arrhythmia, which led to increased cost of care from $16105 in 2003 to $19310 in 2014 (relative increase 22.9%, P < 0.001).ConclusionThere is overall decline in HCM related hospitalizations but rise in hospitalization among HCM patients with arrhythmias. HCM with arrhythmia accounts for significant inpatient mortality coupled with prolonged hospital stay and increased cost of care. However, there is an encouraging downtrend in the mortality most likely because of improved clinical practice, cardiac screening and primary and secondary prevention strategies.