Medical Optimization of Patients with Symptomatic Peripheral Arterial Disease

Peripheral artery disease (PAD) is a progressive disease associated with the occurrence of major adverse cardiovascular and limb events and elevated mortality rates. Symptoms of PAD, including claudication and chronic limb-threatening ischemia, impair functional capacity and lead to lower quality of life. The focus of current therapies is to minimize symptoms, improve quality of life, and reduce adverse cardiovascular and limb events. Among the medical therapies are antiplatelets, anticoagulants, antihypertensives, lipid lowering therapies, cilostazol and pentoxifylline, and novel blood sugar-lowering therapies, plus exercise therapy and smoking cessation. In this review, we discuss these evidence-based medical therapies that are available for patients with symptomatic PAD.

Perioperative outcomes of hypertrophic cardiomyopathy: An insight from the National Readmission Database

BACKGROUND

Data regarding hypertrophic obstructive cardiomyopathy (HOCM) patients undergoing noncardiac surgery is lacking. We sought to examine the perioperative outcomes of HOCM patients undergoing noncardiac surgery using a national database.

METHODS

We used the National readmission database from 2016 to 2019. We identified HOCM, heart undergoing noncardiac surgery using ICD 10 codes. We examined hospital outcomes as well as 90 days readmission outcomes.

RESULTS

We identified 16,098 HOCM patients and 21,895,699 non-HOCM patients undergoing noncardiac surgery. The HOCM group had more comorbidities at baseline. After adjustment for major clinical predictors, the HOCM group experienced more in-hospital death, odds ratio (OR) 1.33 (1.216-1.47), P < 0.001, acute myocardial infarction (AMI), OR 1.18 (1.077-1.292), P < 0.001, acute heart failure odds ratio OR 1.3 to (1.220-1.431), P < 0.001, 90 days readmission OR 1.237 (1.069-1.432), P < 0.01, cardiogenic shock OR 2.094 (1.855-2.363), P < 0.001. Cardiac arrhythmia was the most common cause of readmission, out of the arrhythmias atrial fibrillation was the most prevalent. Acute heart failure was the most common complication of readmission. There was no difference in major adverse cardiovascular events (MACE), and AMI between both groups and readmission.

CONCLUSION

HOCM patients undergoing noncardiac surgery may be at increased risk of in-hospital and readmission events. Acute heart failure was the most common complication during index admission, while cardiac arrhythmias were the most common complication during readmission. More research is needed to address this patient population further.

Trends and outcomes of lytic-based therapies for high-risk pulmonary embolism: A nationwide analysis

BACKGROUND

Systemic thrombolysis (ST) is the guideline-recommended treatment for high-risk pulmonary embolism (PE), although catheter-directed thrombolysis (CDT) may provide a treatment alternative associated with lower rates of bleeding. Furthermore, the treatment trends and outcomes among those with high-risk PE according to treatment assignments of no lytic therapy (NLT), ST, and CDT are underreported.

METHODS

Patients hospitalized for high-risk PE between 2016 and 2019 were identified by administrative claims codes from the National Readmission Database. Therapy assignment was similarly defined by administrative codes, then stratified into NLT, ST, and CDT cohorts to report patient characteristics, care settings, and clinical outcomes. The primary outcome was in-hospital mortality with rates adjusted for patient and hospital characteristics using multivariable logistic regression. Secondary outcomes included intracranial hemorrhage (ICH), gastrointestinal bleeding (GIB), and 90-day readmission. Over the years of interest, trends in lytic treatment along with concomitant use of mechanical or surgical thrombectomy were reported.

RESULTS

Among 74,516 patients with high-risk PE, 61,569 (82.6%) received NLT, 8445 (11.3%) received ST, and 4502 (6.04%) received CDT. The NLT subgroup, relative to ST and CDT, tended to be older (66.1 ± 15.4, 62.8 ± 15.3, and 63.4 ± 14.4; p < 0.001) and more frequently women (56.0%, 54.4%, and 51.3%; p < 0.001), respectively. The unadjusted in-hospital mortality rate was highest for ST (18.8%, 34.1%, and 18.3% for NLT, ST, and CDT, respectively; p < 0.001) and persisted after multivariable adjustment (adjusted odds ratio (aOR) 0.43; 95% CI 0.38-0.49; p < 0.0001) of in-hospital mortality for CDT relative to ST. The unadjusted rate of ICH or GIB was lowest for NLT (1.0%, 2.0%, and 0.6% for NLT, ST, and CDT, respectively; p < 0.001). CDT, relative to ST, was associated with reduced odds of ICH (aOR 0.32; 95% CI 0.18-0.55; p < 0.0001) and GIB (aOR 0.78; 95% CI 0.62-0.98; p < 0.0001). Readmissions were highest for NLT (21.7%, 9.6%, and 12.1% for NLT, ST, and CDT, respectively; p < 0.001). CDT was associated with a higher incidence of 90-day readmission relative to ST (aOR 1.32; 95% CI 1.10-1.57; p < 0.001). From 2016 to 2019, individual treatment trends were not significantly different, although NLT tended to be offered among smaller and rural hospitals. Rates of concomitant thrombectomy were low in all three treatment groups.

CONCLUSIONS

Among a large, contemporary, US cohort with high-risk PE, over 80% of patients did not receive any form of thrombolysis. High-risk PE that did receive systemic thrombolysis was associated with the highest rates of in-hospital mortality, suggesting opportunities to study the implementation of lytic and nonlytic-based treatments to improve outcomes for those presenting with high-risk PE.

Safety and outcomes of hip and knee replacement surgery in liver transplant recipients

BACKGROUND

Liver transplant (LT) is becoming increasingly common with improved life expectancy. Joint replacement is usually a safe procedure; however, its safety in LT recipients remains understudied.

AIM

To evaluate the mortality, outcome, and 90-d readmission rate in LT patients undergoing hip and knee replacement surgery.

METHODS

Patients with history of LT who underwent hip and knee replacement surgery between 2016 and 2019 were identified using the National Readmission Database.

RESULTS

A total of 5046119 hip and knee replacement surgeries were identified. 3219 patients had prior LT. Mean age of patients with no history of LT was 67.51 [95% confidence interval (CI): 67.44-67.58], while it was 64.05 (95%CI: 63.55-64.54) in patients with LT. Patients with history of LT were more likely to have prolonged length of hospital stay (17.1% vs 8.4%, P < 0.001). The mortality rate for patients with no history of LT was 0.22%, while it was 0.24% for patients with LT (P = 0.792). Patients with history of LT were more likely to have re-admissions within 90 d of initial hospitalization: 11.4% as compared to 6.2% in patients without history of LT (P < 0.001). The mortality rate between both groups during readmission was not statistically different (1.9% vs 2%, P = 0.871) respectively.

CONCLUSION

Hip and knee replacements in patients with history of LT are not associated with increased mortality; increased re-admissions were more frequent in this cohort of patients. Chronic kidney disease and congestive heart failure appear to predict higher risk of readmission.

Site Variability in Cerebral Embolic Protection for Transcatheter Aortic Valve Implantation and Association With Outcomes

Background

The effectiveness of cerebral embolic protection devices (CEPD) in mitigating stroke after transcatheter aortic valve implantation (TAVI) remains uncertain, and therefore CEPD may be utilized differently across US hospitals. This study aims to characterize the hospital-level pattern of CEPD use during TAVI in the US and its association with outcomes.

Methods

Patients treated with nontransapical TAVI in the 2019 Nationwide Readmissions Database were included. Hospitals were categorized as CEPD non-users and CEPD users. The following outcomes were compared: the composite of in-hospital stroke or transient ischemic attack (TIA), in-hospital ischemic stroke, death, and cost of hospitalization. Logistic regression models were used for risk adjustment of clinical outcomes.

Results

Of 41,822 TAVI encounters, CEPD was used in 10.6% (n = 4422). Out of 392 hospitals, 65.8% were CEPD non-user hospitals and 34.2% were CEPD users. No difference was observed between CEPD non-users and CEPD users in the risk of in-hospital stroke or TIA (adjusted odds ratio (OR) = 0.99 [0.86-1.15]), ischemic stroke (adjusted OR = 1.00 [0.85-1.18]), or in-hospital death (adjusted OR = 0.86 [0.71-1.03]). The cost of hospitalization was lower in CEPD non-users.

Conclusions

Two-thirds of hospitals in the US do not use CEPD for TAVI, and no significant difference was observed in neurologic outcomes among patients treated at CEPD non-user and CEPD user hospitals.

Temporal trends in the utilization of advanced therapies among patients with acute pulmonary embolism: insights from a national database

There is a paucity of data regarding the contemporary temporal trends in the adoption of advanced pulmonary embolism (PE) therapies in the United States as well as the parallel trends in outcomes of patients with acute PE. Therefore, we queried the Nationwide Readmissions Database (years 2016-2020) to report the temporal trends in utilization of advanced PE therapies. Our final analysis included 920 770 hospitalizations with acute PE. We demonstrated an increase in the proportion of patients diagnosed with high-risk PE during the study years. Overall, there was an increase in the use of advanced PE therapies, which was mainly due to the increase in the utilization of systemic thrombolytics, and catheter-directed therapies. Also, extracorporeal membrane oxygenation cannulation showed an incremental increase over the study years. The use of inferior vena cava filter has declined, while the use of surgical embolectomy did not change during the study years. The use of advanced therapies has increased among urban teaching, but not among urban non-teaching hospitals. During the study years, there was no change in unadjusted or adjusted in-hospital mortality rates among patients with acute PE, while the 90-day unplanned readmission rate has declined.

Outcomes of Transcatheter Aortic Valve Implant Among Patients With A Previous Coronary Artery Bypass Graft: A Nationwide Analysis

There is a paucity of data regarding the temporal trends and outcomes of transcatheter aortic valve implant (TAVI) among patients with a previous coronary artery bypass graft (CABG) surgery. We queried the Nationwide Readmissions Database (2016 to 2019) for hospitalized patients who underwent TAVI using the appropriate International Classification of Diseases, Tenth Revision procedural codes. A multivariable regression analysis was used to adjust for the patients' and hospitals' characteristics in comparing the study groups. The primary outcome was in-hospital mortality. The final analysis included 237,829 patients who underwent TAVI, of whom 42,671 (17.9%) had a previous CABG. During the study period, there was a decrease in the proportion of patients with previous CABG who underwent TAVI (21.0% in 2016 vs 15.5% in 2019, ptrend = 0.01), although there was no change in their in-hospital mortality rate (1.08% in 2016 vs 1.25% in 2019, ptrend = 0.43). Patients with a previous CABG were younger and less likely to be women than those without a previous CABG. TAVI among those with a previous CABG was associated with lower in-hospital mortality (adjusted odds ratio [aOR] 0.79, 95% confidence interval [CI] 0.69 to 0.91), similar rate of ischemic stroke (aOR 0.81, 95% CI 0.71 to 0.93) and permanent pacemaker implant (aOR 1.00, 95% CI 0.93 to 1.05). Patients with a previous CABG had a lower all-cause 90-day readmission (odds ratio 0.95, 95% CI 0.94 to 1.06) but higher readmission for transient ischemic attack. Among those with a previous CABG, female gender and chronic kidney disease stage ≥3 were independently associated with a higher in-hospital mortality, whereas obesity was associated with a lower in-hospital mortality. In conclusion, there was a decrease in the proportion of patients with a previous CABG among those who underwent TAVI. TAVI among those with a previous CABG was not associated with increased in-hospital adverse events or 90-day all-cause readmissions.

A modern day perspective on smoking in peripheral artery disease

Peripheral artery disease (PAD) is associated with increased risk of cardiovascular morbidity and mortality, poor functional status, and lower quality of life. Cigarette smoking is a major preventable risk factor for PAD and is strongly associated with a higher risk of disease progression, worse post-procedural outcomes, and increased healthcare utilization. The arterial narrowing due to atherosclerotic lesions in PAD leads to decreased perfusion to the limbs and can ultimately cause arterial obstruction and limb ischemia. Endothelial cell dysfunction, oxidative stress, inflammation, and arterial stiffness are among the key events during the development of atherogenesis. In this review, we discuss the benefits of smoking cessation among patients with PAD and the use of smoking cessation methods including pharmacological treatment. Given that smoking cessation interventions remain underutilized, we highlight the importance of incorporating smoking cessation treatments as part of the medical management of patients with PAD. Regulatory approaches to reduce the uptake of tobacco product use and support smoking cessation have the potential to reduce the burden of PAD.

Outcomes in hypertrophic obstructive cardiomyopathy patients undergoing non-cardiac surgery-a nationwide analysis

Introduction

Patients with hypertrophic obstructive cardiomyopathy (HOCM) have a unique pathophysiological profile that increases their chances of having adverse events in the postoperative period following surgical procedures. Owing to the rarity of the disease, few studies are available for assessing readmission risk in HOCM patients undergoing noncardiac surgical procedures.

Purpose

Our study aimed to assess 30-day readmission rates and causes for readmissions among HOCM patients who had undergone noncardiac surgeries in hospitals across the United States (US).

Methods

We used appropriate International Classification of Diseases Code, 10th Revision Clinical Modification (ICD-10-CM) codes to identify patients who had been admitted for non-cardiac surgeries between January 2016 and December 2019 based on data from the National Readmissions Database (NRD). The NRD is a publicly available all-payer in-patient database sponsored by the Agency for Healthcare Research and Quality, containing discharge data from approximately 18 million discharges each year, accounting for 61.8% of the total US resident population. Patients were subdivided into two sub-groups based on the presence or absence of HOCM. 30-day readmission rates and causes of readmissions were compared between both groups. STATA version 17 (College Station,TX: StataCorp LLC) was used for statistical analyses.

Results

A total of 5,497,134 patients out of whom 2,089 had HOCM were identified and included for analysis. Patients with HOCM had statistically significant higher rates of readmissions for central nervous system related complications such as stroke or transient ischemic attack (TIA), cardiogenic shock, acute heart failure, unspecified iatrogenic cardiac complications, acute kidney injury, sepsis in addition to higher rates of post op respiratory failure, acute myocardial infarction and major adverse cardiovascular and cerebrovascular events (MACCE) during the index admission when compared to the other subgroup.

Conclusion

Our study, despite being retrospective in nature, is one of the largest to date assessing readmission risk in HOCM patients undergoing noncardiac surgeries. Similar to previous studies, HOCM patients have higher rates of readmissions and MACCE in the 30-day period following noncardiac surgical procedures. In light of these findings, shared medical decision making and appropriate counseling regarding complications in the postoperative period will be necessary for HOCM patients who undergo noncardiac surgical procedures.

Funding Acknowledgement

Type of funding sources: None.

Abstract 194: Impact Of Psoriasis On The Outcomes Of St-elevation Myocardial Infarction From The Nationwide Readmission Database

Background: Psoriasis is a chronic inflammatory disease which causes atherosclerosis. There is conflicting data regarding the association between psoriasis and the development of cerebrovascular diseases with increased mortality. There is also limited data about the outcomes of the psoriatic patients presenting with ST-elevation myocardial infarction (STEMI).

Methods: We queried the Nationwide Readmissions Database (years: 2016-2019) using ICD-10 codes for patients with a primary diagnosis of STEMI who underwent primary percutaneous coronary intervention (PCI). Patients were classified into two groups according to the presence of psoriasis. Outcomes included in-hospital mortality, index admission compilations, 90-day readmission rate, and causes of readmissions.

Results: A total of 52,796 patients with STEMI underwent PCI including 308 with psoriasis and 52,488 with no psoriasis. Mean age and gender were similar between both groups. Psoriasis patients had more prevalence of obesity, diabetes mellitus (DM) obstructive sleep apnea (OSA) and depression. In-hospital mortality rate was not significantly different between the two groups. The length of stay and the total charges were higher in the psoriasis group (Table 1). During the index admission, the most common complications were not different. However, hemorrhagic anemia was higher in the psoriatic group. There were 6,896 (13.1%) readmission in the non-psoriasis group compared to 28 (9.1%).

Conclusion: Patients with psoriasis had higher prevalence of cardiovascular risk factors including obesity, OSA, and DM, without a significant increase in the in-hospital mortality and the 90-day readmission rate.

Abstract 179: Impact Of Age On Catheter Ablation For Atrial Fibrillation In Octogenarians

Introduction: Patients undergoing catheter ablation for atrial fibrillation (CA-AF) often have significant co-morbidities. Although multiple comorbidities increase with age, outcomes of CA-AF), particularly, in older patients has been conflicting.

Methods: The International Classification of Diseases Code, 10 th Revision Clinical Modification (ICD-10) was used to identify patients hospitalized for CA-AF between 2016-2019 from the National Readmission database (NRD). Patients were classified into two groups, those younger than 80 years and older than 80 years. Ninety-day readmission rates and causes of readmission were compared. Adjusted multivariate regression analysis was used to identify factors associated with readmissions.

Results: We identified 40,174 patients who underwent CA-AF from this cohort, 5875 (14.6%) patients were above the age of 80 years and these patients were more likely to have congestive heart failure (72.8% vs 42.6 %), valvular disease (39.3% vs 20.4), pulmonary vascular disorders (18.5% vs 7.4%), chronic pulmonary disease (29.9% vs 23%) and renal failure (35.7% vs 16.6%). In addition, patients >80 years had longer hospital length of stay, higher rates of major adverse cardiovascular events (6.4% vs 3.5%; p<0.0001), acute heart failure and sepsis during their index admission when compared with patients < 80 years. A total of 1201 (20.4%) patients above age for 80 years were readmitted within 90 days as compared to 4295 (12.5%) below the age of 80 years ( p<0.001). Acute heart failure, AF and acute kidney injury were the most common causes for readmission. The following factors were associated with higher risk of readmission in multivariate regression analysis: length of stay > 4 days (OR 1.36 95% CI 1.17-1.91, P<0.0001), chronic pulmonary disease (OR 1.35 95%1.17-1.55, P<0.0001) and renal failure (OR 1.25 95% CI 1.006-1.55, p=0.04).

Conclusion: Age > 80 years is associated with increased risk of complications and higher readmission post CA-AF in patients with OSA . Shared medical decision making for octogenarians with AF should consider these data and alternative treatment strategies when appropriate.

Abstract 188: Ischemic Heart Disease Burden On Clinical Outcomes After Percutaneous Left Atrial Appendage Closure In Patients With Atrial Fibrillation In The United States

Background: Percutaneous left atrial appendage closure (PLAAC) is an alternative to anticoagulants for atrial fibrillation patients with elevated stroke risk and contraindication to anticoagulation. We examined the burden of IHD on clinical outcomes after PLAAC.

Methods: We identified patients from the Nationwide Readmission Database who underwent PLAAC with a Watchman device between 2014-2018 using ICD-9 and 10 codes. Patients were classified into 2 groups based on the presence of IHD. Outcomes were all-cause and cause-specific 30-day readmissions and mortality rate during readmission. Multivariable regression was conducted for 30 days readmission adjusting for patient demographics,hospital characteristics, and Elixhauser Comorbidity Index.

Results: A total of 18,348 Watchman recipients were identified, of which 8,504 had IHD while 9,844 had no ischemic heart disease (NIHD). Length of stay and cost were not different between groups. However, significant differences were noted in terms of the number of frequent index admission complications between the IHD vs. NIHD group, including transient ischemic attack/Stroke (3.5% Vs. 1.6%, P<0.0001) (Table 1). Although the 30 days readmission rate was higher in the IHD group (7.5% Vs. 6%, P=0.003), there was no difference in mortality. Most frequent causes of readmissions for IHD Vs. NIHD were Acute Kidney Injury (AKI) (26% Vs. 17.3%, P=0.009) and acute heart failure (HF) (24.1% Vs. 17%, P=0.015) (Table 1). In multivariate analysis, ICM PLAAC recipients had higher odds of 30-day readmission compared to NICM (OR=3.7, P=0.4). Renal failure patients have higher odds of 30-day readmission compared to non-renal failure ( OR=1.4, P=0.001).

Conclusion: Thirty-day readmission rate in patients who underwent PLAAC was higher in the IHD group. However, no difference was noted in mortality between both groups. AKI and acute HF were significant causes of readmission in patients with IHD who underwent PLAAC. Further studies exploring these differences may help to prevent these readmissions.

Abstract 201: Weekend Effect On Pulmonary Embolism: Real World Data

Background: Pulmonary embolism (PE) is associated with high morbidity and mortality, there is paucity of data regarding the outcomes of patients with acute high-risk PE presenting on weekends, weekend Effect stems from reductions in staff availability, lack of highly trained endovascular subspecialists to conduct timely therapeutic procedures or inadequate intensive care facilities.

Methods: We queried the Nationwide Readmissions Database (2016-2019) using ICD-10 codes for patients presenting with acute PE as primary diagnosis, we classified the patients into 2 groups based on whether patients were admitted on weekends or weekdays. We performed a subgroup analysis of patients presenting with high risk PE (shock or cardiac arrest) during the index admission. Outcomes were in-hospital death, stroke (composite of ischemic, hemorrhagic strokes &TIA), intracranial bleed (IC), gastrointestinal (GI) bleed, and 90-day readmission rates.

Results: 167,522, and 55352 patients were admitted on weekends and weekdays, in hospital-mortality was higher for patients presenting on weekends (3.2% vs 2.9%, p<0.0001). Length of stay and total charges were similar between both groups. Weekends’ group had higher readmission rate within 90 days (14.0 vs. 13.6%, p=0.03). Causes of readmissions were also similar (table1). 5,889 and 17,532 patients were admitted on weekends and weekdays with high-risk PE (shock or cardiac arrest). In-hospital mortality rate was not different between groups 45.2% vs. 44.0%, P=0.4, respectively.

Conclusion: PE patients admitted on weekends have higher mortality rates compared to patients admitted on weekdays. Of those surviving index admissions, weekend patients were also more likely to be readmitted at 90 days. Strategies to mitigate this Weekend Effect should be further explored to reduce mortality and complications.

Abstract 14581: Impact of Heart Failure on 30-day Readmissions After Transcatheter Left Atrial Appendage Occlusion With the Watchman Device

Background: The Watchman device reduces the risk of stroke in select patients with atrial fibrillation (AF). AF commonly coexists with heart failure (HF) and these conditions harbor interrelated pathophysiological mechanisms and treatment strategies., the impact of comorbid heart failure on outcomes in patients with AF undergoing Watchman device implantation remains unclear.

Methods: We identified patients from the Nationwide Readmission Database who underwent Watchman device placement between 2014-2018 using ICD-9 and 10 codes. Patients were classified into 2 groups based on the presence of HF. Outcomes were all-cause and cause-specific 30-day readmissions and mortality rate during readmission. Kaplan-Meier analysis was used to assess the association of HF with 30-day hospital readmission.

Results: We identified 18,349 recipients, 13,180 had no heart failure (NHF) while 5169 had HF. Mean age was similar between both groups. A total of 789 (5.9%) were readmitted within 30 days in the NHF compared to 439 (8.5%) in the non HF (NHF) group, The 30-day readmission rate was higher and Length of the stay was slightly longer in HF group. Prior stroke was more prevalent in the NHF group. Coronary artery disease, smoking, prior ICD, and obesity were more prevalent among HF group as demonstrated in table 1. The most common causes of readmissions for NHF vs HF were (acute heart failure: 15 vs 30%, p<0.001), (GI bleed: 19 vs 23%, P=0.16), and (AKI: 19 vs 27%, P<0.002). No difference in mortality or time-to readmission observed between both groups (Fig.1).

Conclusion: In this analysis, post-Watchman 30-day readmission frequency was higher in patients with HF compared with NHF, though the time-to readmission was similar. Interestingly, 1 in 7 patients with NHF at baseline was readmitted with acute HF. Additional studies are now needed to identify which triggers are responsible for these readmissions so that effective preventive efforts can be instituted to reduce these readmissions.

Efficacy and safety of direct oral anticoagulants in morbidly obese patients with non-valvular atrial fibrillation: a systematic review and meta-analysis

Introduction

Atrial fibrillation (AF) is the most common arrhythmia, with an estimated prevalence between 1–4%. On the other hand, obesity continued to be a prevalent health issue worldwide. Direct oral anticoagulants (DOACs) have been increasingly preferred over warfarin; however, The International Society of Thrombosis and Hemostasis (ISTH) recommended avoiding the use of DOACs in patients with a BMI &gt;40 or weight &gt;120 kg because of limited clinical data in these patients. In this meta-analysis, we aimed to evaluate the efficacy and safety of DOACs in morbidly obese patients with non-valvular AF.

Method

We performed a comprehensive literature search using multiple databases from database inception through January 2021, for all the studies that evaluated the efficacy and safety of DOACs in morbidly obese patients with non-valvular AF. The primary outcome of interest was stroke or systemic embolism (SSE) rate. The secondary outcome was major bleeding (MB). All meta-analyses were conducted using a random-effect model.

Results

A total of 10 studies including 89,494 morbidly obese patients (BMI &gt;40 or weight &gt;120 kg) with non-valvular AF on oral anticoagulation therapy (45427 on DOACs vs. 44067 on warfarin) were included in the final analysis. One included study was a randomized controlled trial (RCT), another study was a post hoc analysis of an RCT and the rest were retrospective cohort studies. The mean follow-up period was 1.8 years (range 8 months to 3.1 years). The SSE rate was significantly lower in DOACs group compared to warfarin group (odds ratio (OR): 0.71; 95% confidence interval (CI): 0.62, 0.81; p&lt;0.0001; I2=0%). MB rate was also significantly lower in DOACs group compared to the warfarin group (OR 0.60, 95% CI 0.46–0.78, P&lt;0.0001, I2=86%). Subgroup analysis in the rivaroxaban and apixaban AF cohort showed a statistically significant difference in SSE and MB event rates favoring both over warfarin therapy. Dabigatran showed non-inferiority to warfarin in SSE rate but superiority in the safety outcome.

Conclusions

Our meta-analysis demonstrated that DOACs are effective and safe when compared to warfarin in morbidly obese patients. However, more large scale randomized clinical trials are needed to further evaluate the efficacy and safety of DOACs compared to warfarin in this cohort of patients.

Funding Acknowledgement

Type of funding sources: None. Stroke and systemic embolism eventsMajor bleeding events

Impact of kidney disease on left ventricular assisted device outcomes: insight from National Readmission Database

Introduction

Improvements in device technology, appropriate patient selection and timing of left ventricular assist device (LVAD) implantation have allowed this technique as the preferred destination therapy for advanced end-stage heart failure (HF) patients whom are not candidates for heart transplantation. Unfortunately, up to a third of these patients still experience poor outcomes following LVAD implantation. Although some clinical factors have been identified as potential risk factors for these poor outcomes, there is paucity of data regarding the impact of baseline kidney disease following LVAD implantation.

Methods

We used the Nationwide Readmission Database (NRD), identifying patients who underwent implantable LVAD placement 2010–2017 using ICD-9 and 10 codes. Patients were stratified into 3 mutually exclusive groups based on presence and severity of chronic kidney disease (CKD) during the LVAD placement hospitalization: non-CKD, CKD and end stage renal disease requiring dialysis (CKD-D). Outcomes were all-cause and cause-specific 30-day readmissions as well as 90-day readmission.

Result

Within 30 days after discharge 28.5% of patients were readmitted. Of those without CKD, 27.8% were readmitted, compared to 29% of those with CKD and 31% of those with CKD-D. Compared to non-CKD (adjusted for demographics, index hospitalization and chronic comorbidity factors, and year), odds of 30-day readmission were 1.542 [95% CI 1.028–2.313] times higher for those with CKD-D, whereas those with CKD had similar 30-day readmission risk (OR 1.074 [95% CI 0.951–1.213]). Those with CKD and CKD-D had higher risk of 30-day readmission for acute (HF), bleeding and transfusion need.

Within 90 days after discharge 48.88% of patients were readmitted. Of those without CKD, 46.2% were readmitted, compared to 50%of those with CKD and 45% of those with CKD-D. Odds of 90-day readmission were 1.203 (95% CI 1.088–1.330) times higher for those with CKD than non-CKD group, Also those with CKD-D requiring dialysis had higher 90-day readmission risk (OR 1.287 [95% CI 0.954–1.736]) when compared to non-CKD. Those with CKD had higher risk of 90-day readmission for acute (HF), gastrointestinal bleeding and arrhythmia while those with CKD-D had higher risk of 90-day readmission for DVT and anemia. There was no difference in 30-day and 90-day readmission between all groups for stroke, device related thrombosis or infection.

Conclusion

It appears, based on our analysis, that although having CKD does not confer additional risk for either 30 or 90-days readmissions; these post LVAD patients have a greater risk of acute HF exacerbation, bleeding and arrhythmias. We believe that these results are very important and should be included into future risk models when deciding on LVAD implantation.

Funding Acknowledgement

Type of funding sources: None.

The association between tonsillectomy and Hodgkin’s lymphoma: A systematic review and meta-analysis

e20015

Background: Several observational studies have evaluated tonsillectomy as a predisposing factor for developing Hodgkin’s lymphoma (HL) with contradicting results. The true association is unknown. We sought to systematically review the literature and perform the first meta-analysis to study the association between a history of tonsillectomy and the development of HL. Methods: A systematic review was conducted in Pubmed, and Cochrane databases from inception through January 2020 to identify the studies which explored the association between history of tonsillectomy and HL. Effect estimates from the individual studies were extracted and combined using the random effect, generic inverse variance method of DerSimonian and Laird and a pooled odds ratio (OR) was calculated. A forest plot was generated, and publication bias was assessed for using conventional techniques. Results: Twenty studies with a total of 17931 patients were included in our analysis. 6231 of the patients were diagnosed with HL. The pooled OR for the development of HL in patients with history of tonsillectomy was 1.237 (CI 1.075-1.424, P = 0.003, I2= 45.073%) compared to patients without a history of tonsillectomy. Conclusions: Our analysis shows a statistically significant association between a history of tonsillectomy and the development of HL. As all the studies included in our meta-analysis were observational, we need prospective studies to better understand this important association.

In a Phase 1a escalating clinical trial, autologous mesenchymal stem cell infusion for renovascular disease increases blood flow and the glomerular filtration rate while reducing inflammatory biomarkers and blood pressure

Atherosclerotic renovascular disease (ARVD) reduces tissue perfusion and eventually leads to loss of kidney function with limited therapeutic options. Here we describe results of Phase 1a escalating dose clinical trial of autologous mesenchymal stem cell infusion for ARVD. Thirty-nine patients with ARVD were studied on two occasions separated by three months. Autologous adipose-derived mesenchymal stem cells were infused through the renal artery in 21 patients at three different dose levels (1, 2.5 and 5.0 × 105 cells/kg) in seven patients each. We measured renal blood flow, glomerular filtration rate (GFR) (iothalamate and estimated GFR), renal vein cytokine levels, blood pressure, and tissue oxygenation before and three months after stem cell delivery. These indices were compared to those of 18 patients with ARVD matched for age, kidney function and blood pressure receiving medical therapy alone that underwent an identical study protocol. Cultured mesenchymal stem cells were also studied in vitro. For the entire stem cell treated-cohort, mean renal blood flow in the treated stenotic kidney significantly increased after stem cell infusion from (164 to 190 ml/min). Hypoxia, renal vein inflammatory cytokines, and angiogenic biomarkers significantly decreased following stem cell infusion. Mean systolic blood pressure significantly fell (144 to 136 mmHg) and the mean two-kidney GFR (Iothalamate) modestly but significantly increased from (53 to 56 ml/min). Changes in GFR and blood pressure were largest in the high dose stem cell treated individuals. No such changes were observed in the cohort receiving medical treatment alone. Thus, our data demonstrate the potential for autologous mesenchymal stem cell to increase blood flow, GFR and attenuate inflammatory injury in post-stenotic kidneys. The observation that some effects are dose-dependent and related to in-vitro properties of mesenchymal stem cell may direct efforts to maximize potential therapeutic efficacy.

A modified two-compartment model for measurement of renal function using dynamic contrast-enhanced computed tomography

Objectives

To validate and adapt a modified two-compartment model, originally developed for magnetic resonance imaging, for measuring human single-kidney glomerular filtration rate (GFR) and perfusion using dynamic contrast-enhanced computed tomography (DCE-CT).

Methods

This prospective study was approved by the institutional review board, and written informed consent was obtained from all patients. Thirty-eight patients with essential hypertension (EH, n = 13) or atherosclerotic renal artery stenosis (ARAS, n = 25) underwent renal DCE-CT for GFR and perfusion measurement using a modified two-compartment model. Iothalamate clearance was used to measure reference total GFR, which was apportioned into single-kidney GFR by renal blood flow. Renal perfusion was also calculated using a conventional deconvolution algorithm. Validation of GFR and perfusion and inter-observer reproducibility, were conducted by using the Pearson correlation and Bland-Altman analysis.

Results

Both the two-compartment model and iothalamate clearance detected in ARAS patients lower GFR in the stenotic compared to the contralateral and EH kidneys. GFRs measured by DCE-CT and iothalamate clearance showed a close match (r = 0.94, P<0.001, and mean difference 2.5±12.2mL/min). Inter-observer bias and variation in model-derived GFR (r = 0.97, P<0.001; mean difference, 0.3±7.7mL/min) were minimal. Renal perfusion by deconvolution agreed well with that by the compartment model when the blood transit delay from abdominal aorta to kidney was negligible.

Conclusion

The proposed two-compartment model faithfully depicts contrast dynamics using DCE-CT and may provide a reliable tool for measuring human single-kidney GFR and perfusion.

Urinary mitochondrial DNA copy number identifies renal mitochondrial injury in renovascular hypertensive patients undergoing renal revascularization: A Pilot Study

AIMS

Patients with renovascular hypertension (RVH) exhibit elevated urinary mtDNA copy numbers, considered to constitute surrogate markers of renal mitochondrial injury. The modest success of percutaneous transluminal renal angioplasty (PTRA) in restoring renal function in RVH has been postulated to be partly attributable to acute reperfusion injury. We hypothesized that mitoprotection during revascularization would ameliorate PTRA-induced renal mitochondrial injury, reflected in elevated urinary mtDNA copy numbers and improve blood pressure and functional outcomes 3 months later.

METHODS

We prospectively measured urinary copy number of the mtDNA genes COX3 and ND1 using qPCR in RVH patients before and 24 hrs after PTRA, performed during IV infusion of vehicle (n = 8) or the mitoprotective drug elamipretide (ELAM, 0.05 mg/kg/h, n = 6). Five healthy volunteers (HV) served as controls. Urinary mtDNA levels were also assessed in RVH and normal pigs (n = 7 each), in which renal mitochondrial structure and density were studied ex-vivo.

RESULTS

Baseline urinary mtDNA levels were elevated in all RVH patients vs HV and directly correlated with serum creatinine levels. An increase in urinary mtDNA 24 hours after PTRA was blunted in PTRA+ELAM vs PTRA+Placebo. Furthermore, 3-months after PTRA, systolic blood pressure decreased and estimated glomerular filtration rate increased only in ELAM-treated subjects. In RVH pigs, mitochondrial damage was observed using electron microscopy in tubular cells and elevated urinary mtDNA levels correlated inversely with renal mitochondrial density.

CONCLUSIONS

PTRA leads to an acute rise in urinary mtDNA, reflecting renal mitochondrial injury that in turn inhibits renal recovery. Mitoprotection might minimize PTRA-associated mitochondrial injury and improve renal outcomes after revascularization.

Loss of Renal Peritubular Capillaries in Hypertensive Patients Is Detectable by Urinary Endothelial Microparticle Levels

Hypertension, an important cause of chronic kidney disease, is characterized by peritubular capillary (PTC) loss. Circulating levels of endothelial microparticles (EMPs) reflect systemic endothelial injury. We hypothesized that systemic and urinary PTC-EMPs levels would reflect renal microvascular injury in hypertensive patients. We prospectively measured by flow cytometry renal vein, inferior vena cava, and urinary levels of EMPs in essential (n=14) and renovascular (RVH; n=24) hypertensive patients and compared them with peripheral blood and urinary levels in healthy volunteers (n=14). PTC-EMPs were identified as urinary exosomes positive for the PTC marker plasmalemmal-vesicle-associated protein. In 7 RVH patients, PTC and fibrosis were also quantified in renal biopsy, and in 18 RVH patients, PTC-EMPs were measured again 3 months after continued medical therapy with or without stenting (n=9 each). Renal vein and systemic PTC-EMPs levels were not different among the groups, whereas their urinary levels were elevated in both RVH and essential hypertension versus healthy volunteers (56.8%±12.7% and 62.8%±10.7% versus 34.0%±17.8%; both P≤0.001). Urinary PTC-EMPs levels correlated directly with blood pressure and inversely with estimated glomerular filtration rate. Furthermore, in RVH, urinary PTC-EMPs levels correlated directly with stenotic kidney hypoxia, histological PTC count, and fibrosis and inversely with cortical perfusion. Three months after treatment, the change in urinary PTC-EMPs levels correlated inversely with a change in renal function ( r=-0.582; P=0.011). Therefore, urinary PTC-EMPs levels are increased in hypertensive patients and may reflect renal microcirculation injury, whereas systemic PTC-EMPs levels are unchanged. Urinary PTC-EMPs may be useful as novel biomarkers of intrarenal capillary loss.

Tissue hypoxia, inflammation, and loss of glomerular filtration rate in human atherosclerotic renovascular disease

The relationships between renal blood flow (RBF), tissue oxygenation, and inflammatory injury in atherosclerotic renovascular disease (ARVD) are poorly understood. We sought to correlate RBF and tissue hypoxia with glomerular filtration rate (GFR) in 48 kidneys from patients with ARVD stratified by single kidney iothalamate GFR (sGFR). Oxygenation was assessed by blood oxygenation level dependent magnetic resonance imaging (BOLD MRI), which provides an index for the levels of deoxyhemoglobin within a defined volume of tissue (R2*). sGFR correlated with RBF and with the severity of vascular stenosis as estimated by duplex velocities. Higher cortical R2* and fractional hypoxia and higher levels of renal vein neutrophil-gelatinase-associated-lipocalin (NGAL) and monocyte-chemoattractant protein-1 (MCP-1) were observed at lower GFR, with an abrupt inflection below 20 ml/min. Renal vein MCP-1 levels correlated with cortical R2* and with fractional hypoxia. Correlations between cortical R2* and RBF in the highest sGFR stratum (mean sGFR 51 ± 12 ml/min; R = -0.8) were degraded in the lowest sGFR stratum (mean sGFR 8 ± 3 ml/min; R = -0.1). Changes in fractional hypoxia after furosemide were also absent in the lowest sGFR stratum. These data demonstrate relative stability of renal oxygenation with moderate reductions in RBF and GFR but identify a transition to overt hypoxia and inflammatory cytokine release with severely reduced GFR. Tissue oxygenation and RBF were less correlated in the setting of reduced sGFR, consistent with variable oxygen consumption or a shift to alternative mechanisms of tissue injury. Identifying transitions in tissue oxygenation may facilitate targeted therapy in ARVD.

Intrarenal fat deposition does not interfere with the measurement of single-kidney perfusion in obese swine using multi-detector computed tomography

BACKGROUND

Altered vascular structure or function in several diseases may impair renal perfusion. Multi-detector computed tomography (MDCT) is a non-invasive tool to assess single-kidney perfusion and function based on dynamic changes in tissue attenuation during contrast media transit. However, changes in basal tissue attenuation might hamper these assessments, despite background subtraction. Evaluation of iodine concentration using the dual-energy (DECT) MDCT mode allows excluding effects of basal values on dynamic changes in tissue attenuation. We tested whether decreased basal kidney attenuation secondary to intrarenal fat deposition in swine obesity interferes with assessment of renal perfusion using MDCT.

METHODS

Domestic pigs were fed a standard (lean) or a high-cholesterol/carbohydrate (obese) diet (n = 5 each) for 16 weeks, and both kidneys were then imaged using MDCT/DECT after iodinated contrast injection. DECT images were post-processed to generate iodine and virtual-non-contrast (VNC) datasets, and the MDCT kidney/aorta CT number (following background subtraction) and DECT iodine ratios calculated during the peak vascular phase as surrogates of renal perfusion. Intrarenal fat was subsequently assessed with Oil-Red-O staining.

RESULTS

VNC maps in obese pigs revealed decreased basal cortical attenuation, and histology confirmed increased renal tissue fat deposition. Nevertheless, the kidney/aorta attenuation and iodine ratios remained similar, and unchanged compared to lean pigs.

CONCLUSIONS

Despite decreased basal attenuation secondary to renal adiposity, background subtraction allows adequate assessment of kidney perfusion in obese pigs using MDCT. These observations support the feasibility of renal perfusion assessment in obese subjects using MDCT.