Vallabhajosyula, Saraschandra

Background: The objective of this study was to characterize patients with hyponatremia at hospital admission into clusters using an unsupervised machine learning approach, and to evaluate the short- and long-term mortality risk among these distinct clusters. Methods: We performed consensus cluster analysis based on demographic information, principal diagnoses, comorbidities, and laboratory data among 11,099 hospitalized adult hyponatremia patients with an admission serum sodium below 135 mEq/L. The standardized mean difference was utilized to identify each cluster’s key features. We assessed the association of each hyponatremia cluster with hospital and one-year mortality using logistic and Cox proportional hazard analysis, respectively. Results: There were three distinct clusters of hyponatremia patients: 2033 (18%) in cluster 1, 3064 (28%) in cluster 2, and 6002 (54%) in cluster 3. Among these three distinct clusters, clusters 3 patients were the youngest, had lowest comorbidity burden, and highest kidney function. Cluster 1 patients were more likely to be admitted for genitourinary disease, and have diabetes and end-stage kidney disease. Cluster 1 patients had the lowest kidney function, serum bicarbonate, and hemoglobin, but highest serum potassium and prevalence of acute kidney injury. In contrast, cluster 2 patients were the oldest and were more likely to be admitted for respiratory disease, have coronary artery disease, congestive heart failure, stroke, and chronic obstructive pulmonary disease. Cluster 2 patients had lowest serum sodium and serum chloride, but highest serum bicarbonate. Cluster 1 patients had the highest hospital mortality and one-year mortality, followed by cluster 2 and cluster 3, respectively. Conclusion: We identified three clinically distinct phenotypes with differing mortality risks in a heterogeneous cohort of hospitalized hyponatremic patients using an unsupervised machine learning approach.

Acute myocardial infarction with cardiogenic shock (AMI-CS) is associated with high mortality and morbidity despite advancements in cardiovascular care. AMI-CS is associated with multiorgan failure of non-cardiac organ systems. Acute kidney injury (AKI) is frequently seen in patients with AMI-CS and is associated with worse mortality and outcomes compared to those without. The pathogenesis of AMI-CS associated with AKI may involve more factors than previously understood. Early use of renal replacement therapies, management of comorbid conditions and judicious fluid administration may help improve outcomes. In this review, we seek to address the etiology, pathophysiology, management, and outcomes of AKI complicating AMI-CS.

Summary Background Hospitalized patients with hyperkalemia are heterogeneous, and cluster approaches may identify specific homogenous groups. This study aimed to cluster patients with hyperkalemia on admission using unsupervised machine learning (ML) consensus clustering approach, and to compare characteristics and outcomes among these distinct clusters. Methods Consensus cluster analysis was performed in 5133 hospitalized adult patients with admission hyperkalemia, based on available clinical and laboratory data. The standardized mean difference was used to identify each cluster’s key clinical features. The association of hyperkalemia clusters with hospital and 1-year mortality was assessed using logistic and Cox proportional hazard regression. Results Three distinct clusters of hyperkalemia patients were identified using consensus cluster analysis: 1661 (32%) in cluster 1, 2455 (48%) in cluster 2 and 1017 (20%) in cluster 3. Cluster 1 was mainly characterized by older age, higher serum chloride and acute kidney injury (AKI), but lower estimated glomerular filtration rate (eGFR), serum bicarbonate and hemoglobin. Cluster 2 was mainly characterized by higher eGFR, serum bicarbonate and hemoglobin, but lower comorbidity burden, serum potassium and AKI. Cluster 3 was mainly characterized by higher comorbidity burden, particularly diabetes and end-stage kidney disease, AKI, serum potassium, anion gap, but lower eGFR, serum sodium, chloride and bicarbonate. Hospital and 1-year mortality risk was significantly different among the three identified clusters, with highest mortality in cluster 3, followed by cluster 1 and then cluster 2. Conclusion In a heterogeneous cohort of hyperkalemia patients, three distinct clusters were identified using unsupervised ML. These three clusters had different clinical characteristics and outcomes.

Background The role of race and ethnicity in the outcomes of cardiac arrest (CA) complicating acute myocardial infarction (AMI) is incompletely understood. Methods and Results This was a retrospective cohort study of adult admissions with AMI‐CA from the National Inpatient Sample (2012–2017). Self‐reported race/ethnicity was classified as White, Black, and others (Hispanic, Asian or Pacific Islander, Native American, Other). Outcomes of interest included in‐hospital mortality, coronary angiography, percutaneous coronary intervention, palliative care consultation, do‐not‐resuscitate status use, hospitalization costs, hospital length of stay, and discharge disposition. Of the 3.5 million admissions with AMI, CA was noted in 182 750 (5.2%), with White, Black, and other races/ethnicities constituting 74.8%, 10.7%, and 14.5%, respectively. Black patients admitted with AMI‐CA were more likely to be female, with more comorbidities, higher rates of non–ST‐segment–elevation myocardial infarction, and higher neurological and renal failure. Admissions of patients of Black and other races/ethnicities underwent coronary angiography (61.9% versus 70.2% versus 73.1%) and percutaneous coronary intervention (44.6% versus 53.0% versus 58.1%) less frequently compared to patients of white race ( p <0.001). Admissions of patients with AMI‐CA had significantly higher unadjusted mortality (47.4% and 47.4%) as compared with White patients admitted (40.9%). In adjusted analyses, Black race was associated with lower in‐hospital mortality (odds ratio [OR], 0.95; 95% CI, 0.91–0.99; P =0.007) whereas other races had higher in‐hospital mortality (OR, 1.11; 95% CI, 1.08–1.15; P <0.001) compared with White race. Admissions of Black patients with AMI‐CA had longer length of hospital stay, higher rates of palliative care consultation, less frequent do‐not‐resuscitate status use, and fewer discharges to home (all P <0.001). Conclusions Racial and ethnic minorities received less frequent guideline‐directed procedures and had higher in‐hospital mortality and worse outcomes in AMI‐CA.

Background There are limited contemporary data on the use of emergent coronary artery bypass grafting (CABG) in acute myocardial infarction. Methods and Results Adult (aged >18 years) acute myocardial infarction admissions were identified using the National (Nationwide) Inpatient Sample (2000–2017) and classified by tertiles of admission year. Outcomes of interest included temporal trends of CABG use; age‐, sex‐, and race‐stratified trends in CABG use; in‐hospital mortality; hospitalization costs; and hospital length of stay. Of the 11 622 528 acute myocardial infarction admissions, emergent CABG was performed in 1 071 156 (9.2%). CABG utilization decreased overall (10.5% [2000] to 8.7% [2017]; adjusted odds ratio [OR], 0.98 [95% CI, 0.98–0.98]; P <0.001), in ST‐segment–elevation myocardial infarction (10.2% [2000] to 5.2% [2017]; adjusted OR, 0.95 [95% CI, 0.95–0.95]; P <0.001) and non–ST‐segment–elevation myocardial infarction (10.8% [2000] to 10.0% [2017]; adjusted OR, 0.99 [95% CI, 0.99–0.99]; P <0.001), with consistent age, sex, and race trends. In 2012 to 2017, compared with 2000 to 2005, admissions receiving emergent CABG were more likely to have non–ST‐segment–elevation myocardial infarction (80.5% versus 56.1%), higher rates of noncardiac multiorgan failure (26.1% versus 8.4%), cardiogenic shock (11.5% versus 6.4%), and use of mechanical circulatory support (19.8% versus 18.7%). In‐hospital mortality in CABG admissions decreased from 5.3% (2000) to 3.6% (2017) (adjusted OR, 0.89; 95% CI, 0.88–0.89 [ P <0.001]) in the overall cohort, with similar temporal trends in patients with ST‐segment–elevation myocardial infarction and non–ST‐segment–elevation myocardial infarction. An increase in lengths of hospital stay and hospitalization costs was seen over time. Conclusions Utilization of CABG has decreased substantially in acute myocardial infarction admissions, especially in patients with ST‐segment–elevation myocardial infarction. Despite an increase in acuity and multiorgan failure, in‐hospital mortality consistently decreased in this population.

Background: Ranolazine has the potential to prevent atrial fibrillation (AF) and plays a role in rhythm control strategy for atrial fibrillation in various clinical settings. However, data on the use of ranolazine in patients with left ventricular (LV) systolic dysfunction are limited. The aims of this meta-analysis of randomized clinical trials are to investigate the efficacy and safety of ranolazine in AF patients with LV systolic dysfunction. PubMed and the Cochrane Database of Systematic Reviews were searched until July 2020. The efficacy outcomes included the incidence of new-onset AF, the rate of sinus rhythm restoration, and the time until sinus rhythm restoration. Safety endpoints were at death, and any adverse events were reported in the enrolled studies. We initially identified 204 studies and finally retrieved 5 RCTs. Three studies were analyzed in the meta-analysis. Among AF patients with LV systolic dysfunction, our meta-analysis showed that the combination of ranolazine to amiodarone significantly increased the sinus rhythm restoration rate compared to amiodarone alone (risk ratio (RR) 2.87, 95% confidence interval (CI) 2.48–3.32). Moreover, the time to sinus rhythm restoration was 2.46 h shorter in the ranolazine added to amiodarone group (95% CI: 2.27–2.64). No significant adverse events and proarrhythmias in the ranolazine group were identified. In conclusion, in AF patients with LV systolic dysfunction, ranolazine as an add-on therapy to amiodarone potentiates and accelerates the conversion of AF to sinus rhythm. Moreover, ranolazine shows good safety profiles. Further studies to investigate the effectiveness of ranolazine in the prevention of new-onset AF among patients with LV systolic dysfunction are needed.

Abstract Aims This study aims to evaluate the impact of the combination of cardiogenic shock (CS) and cardiac arrest (CA) complicating non-ST-segment elevation myocardial infarction (NSTEMI). Methods and results Adult (&gt;18 years) NSTEMI admissions using the National Inpatient Sample database (2000 to 2017) were stratified by the presence of CA and/or CS. Outcomes of interest included in-hospital mortality, early coronary angiography, hospitalization costs, and length of stay. Of the 7 302 447 hospitalizations due to NSTEMI, 147 795 (2.0%) had CS only, 155 522 (2.1%) had CA only, and 41 360 (0.6%) had both CS and CA. Compared with 2000, the adjusted odds ratios (ORs) and 95% confidence interval (CIs) for CS, CA, and both CS and CA in 2017 were 3.75 (3.58–3.92), 1.46 (1.42–1.50), and 4.52 (4.16–4.87), respectively (all P &lt; 0.001). The CS + CA (61.2%) cohort had higher multiorgan failure than CS (42.3%) and CA only (32.0%) cohorts, P &lt; 0.001. The CA only cohort had lower rates of overall (52% vs. 59–60%) and early (17% vs. 18–27%) angiography compared with the other groups (all P &lt; 0.001). CS + CA admissions had higher in-hospital mortality compared with those with CS alone (aOR 4.12 [95% CI 4.00–4.24]), CA alone (aOR 1.69 [95% CI 1.65–1.74]), or without CS/CA (aOR 22.66 [95% CI 22.06–23.27]). The presence of CS, either alone or with CA, was associated with higher hospitalization costs and longer hospital length of stay. Conclusions The combination of CS and CA is associated with higher rates of acute non-cardiac organ failure and in-hospital mortality in NSTEMI admissions as compared with those with either CS or CA alone.

Racial disparities in utilization and outcomes of mechanical circulatory support (MCS) in patients with acute myocardial infarction-cardiogenic shock (AMI-CS) are infrequently studied. This study sought to evaluate racial disparities in the outcomes of MCS in AMI-CS. The National Inpatient Sample (2012–2017) was used to identify adult AMI-CS admissions receiving MCS support. MCS devices were classified as intra-aortic balloon pump (IABP), percutaneous left ventricular assist device (pLVAD) or extracorporeal membrane oxygenation (ECMO). Self-reported race was classified as white, black and others. Outcomes included in-hospital mortality, hospital length of stay and discharge disposition. During this period, 90,071 admissions were included with white, black and other races constituting 73.6%, 8.3% and 18.1%, respectively. Compared to white and other races, black race admissions were on average younger, female, with greater comorbidities, and non-cardiac organ failure (all p < 0.001). Compared to the white race (31.3%), in-hospital mortality was comparable in black (31.4%; adjusted odds ratio (aOR) 0.98 (95% confidence interval (CI) 0.93–1.05); p = 0.60) and other (30.2%; aOR 0.96 (95% CI 0.92–1.01); p = 0.10). Higher in-hospital mortality was noted in non-white races with concomitant cardiac arrest, and those receiving ECMO support. Black admissions had longer lengths of hospital stay (12.1 ± 14.2, 10.3 ± 11.2, 10.9 ± 1.2 days) and transferred less often (12.6%, 14.2%, 13.9%) compared to white and other races (both p < 0.001). In conclusion, this study of AMI-CS admissions receiving MCS devices did not identify racial disparities in in-hospital mortality. Black admissions had longer hospital stay and were transferred less often. Further evaluation with granular data including angiographic and hemodynamic parameters is essential to rule out racial differences.