Venous and arterial thrombosis in patients with VEXAS syndrome

ABSTRACT

VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome, caused by somatic mutations in UBA1, is an autoinflammatory disorder with diverse systemic manifestations. Thrombosis is a prominent clinical feature of VEXAS syndrome. The risk factors and frequency of thrombosis in VEXAS syndrome are not well described, due to the disease's recent discovery and the paucity of large databases. We evaluated 119 patients with VEXAS syndrome for venous and arterial thrombosis and correlated their presence with clinical outcomes and survival. Thrombosis occurred in 49% of patients, mostly venous thromboembolism (VTE; 41%). Almost two-thirds of VTEs were unprovoked, 41% were recurrent, and 20% occurred despite anticoagulation. The cumulative incidence of VTE was 17% at 1 year from symptom onset and 40% by 5 years. Cardiac and pulmonary inflammatory manifestations were associated with time to VTE. M41L was positively associated specifically with pulmonary embolism by univariate (odds ratio [OR]: 4.58, confidence interval [CI] 1.28-16.21, P = .02) and multivariate (OR: 16.94, CI 1.99-144.3, P = .01) logistic regression. The cumulative incidence of arterial thrombosis was 6% at 1 year and 11% at 5 years. The overall survival of the entire patient cohort at median follow-up time of 4.8 years was 88%, and there was no difference in survival between patients with or without thrombosis (P = .8). Patients with VEXAS syndrome are at high risk of VTE; thromboprophylaxis should administered be in high-risk settings unless strongly contraindicated.

Pulmonary vein thrombosis: Clinical presentation and outcomes

BACKGROUND

Pulmonary vein thrombosis (PVT) is a rare thromboembolic disease with potential high-risk complications related to arterial embolization, but little is known regarding risk factors and outcomes.

OBJECTIVE

To describe the etiology, management, and clinical course of PVT.

METHODS

Institutional health records were queried (1/1/2001-12/30/2023) to identify patients ≥18 years of age diagnosed with PVT. Thrombosis, bleeding, respiratory failure, and all-cause mortality were analyzed. Suspected tumor thrombus cases were excluded.

RESULTS

72 patients with PVT were identified (median age 62 years, 50 % female), and PVT was overall rare at 3.1 diagnosed cases per year at our institution. PVT primarily affected a single vein (89 %), most commonly the left upper PV (40 %). Of these, 37 % occurred while on therapeutic anticoagulation. The most common risk factors included cancer (55 %) and related surgical lobectomy (21 %). Extrinsic vein compression (17 %) and recent surgery (19 %) were also common; 19 % were deemed idiopathic. Most patients (76 %) were treated with anticoagulation and frequently indefinite duration (80 %). During a median follow-up of 11.7 months (IQR 39.5 months), serial imaging (available for 68 %) revealed PVT resolution in 64 %. Four-year Kaplan-Meier probability of outcome included: left atrial thrombus (21 %), need for mechanical ventilation (14 %), pneumonia (9 %), and ischemic stroke (9 %). The mortality rate was 46 % with median survival 14 months after PVT diagnosis.

CONCLUSION

PVT is often associated with active malignancy, lobectomy, recent surgery, and extrinsic vein compression; 1 in 5 cases were idiopathic. Notable complications include left atrial thrombus with arterial embolism including stroke. With anticoagulation, most thrombi resolve over time. Mortality rates are high, reflecting the high the prevalence of cancer.

Calf rEF: Impact of Calf Muscle Pump Dysfunction With Reduced Ejection Fraction on All-Cause Mortality

OBJECTIVE

To evaluate mortality outcomes by varying degrees of reduced calf muscle pump (CMP) ejection fraction (EF).

PATIENTS AND METHODS

Consecutive adult patients who underwent venous air plethysmography testing at the Mayo Clinic Gonda Vascular Laboratory (January 1, 2012, through December 31, 2022) were divided into groups based on CMP EF for the assessment of all-cause mortality. Other venous physiology included measures of valvular incompetence and clinical venous disease (CEAP [clinical presentation, etiology, anatomy, and pathophysiology] score). Mortality rates were calculated using the Kaplan-Meier method.

RESULTS

During the study, 5913 patients met the inclusion criteria. During 2.84-year median follow-up, there were 431 deaths. Mortality rates increased with decreasing CMP EF. Compared with EF of 50% or higher, the hazard ratios (95% CIs) for mortality were as follows: EF of 40% to 49%, 1.4 (1.0 to 2.0); EF of 30% to 39%, 1.6 (1.2 to 2.4); EF of 20% to 29%, 1.7 (1.2 to 2.4); EF of 10% to 19%, 2.4 (1.7 to 3.3) (log-rank P≤.001). Although measures of venous valvular incompetence did not independently predict outcomes, venous disease severity assessed by CEAP score was predictive. After adjusting for several clinical covariates, both CMP EF and clinical venous disease severity assessed by CEAP score remained independent predictors of mortality.

CONCLUSION

Mortality rates are higher in patients with reduced CMP EF and seem to increase with each 10% decrement in CMP EF. The mortality mechanism does not seem to be impacted by venous valvular incompetence and may represent variables intrinsic to muscular physiology.

Reduced calf muscle pump function is not explained by handgrip strength measurements

OBJECTIVE

Reduced calf muscle pump function (CPF) is an independent risk factor for venous thromboembolism and mortality. We aimed to evaluate the relationship between handgrip strength (HGS) and CPF.

METHODS

Patients referred to the Gonda Vascular Laboratory for noninvasive venous studies were identified and consented. Patients underwent standard venous air plethysmography protocol. CPF (ejection fraction) was measured in each lower extremity of ambulatory patients by comparing refill volume after ankle flexes and passive refill volumes. The cutoff for reduced CPF (rCPF) was defined as an ejection fraction of <45%. Maximum HGS bilaterally was obtained (three trials per hand) using a dynamometer. HGS and CPF were compared (right hand to calf, left hand to calf) and the correlation between the measures was evaluated.

RESULTS

115 patients (mean age, 59.2 ± 17.4 years; 67 females, mean body mass index, 30.83 ± 6.46) were consented and assessed for HGS and CPF. rCPF was observed in 53 right legs (46%) and 67 left legs (58%). CPF was reduced bilaterally in 45 (39%) and unilaterally in 30 (26%) patients. HGS was reduced bilaterally in 74 (64.3%), unilaterally in 23 (20%), and normal in 18 (15.7%) patients. Comparing each hand/calf pair, no significant correlations were seen between HGS and CPF. The Spearman's rank correlation coefficients test yielded values of 0.16 for the right side and 0.10 for the left side.

CONCLUSIONS

There is no significant correlation between HGS and CPF, demonstrating that HGS measurements are not an acceptable surrogate for rCPF, indicating different pathophysiological mechanisms for each process.

Artificial intelligence of arterial Doppler waveforms to predict major adverse outcomes among patients with diabetes mellitus

OBJECTIVE

Patients with diabetes mellitus (DM) are at increased risk for peripheral artery disease (PAD) and its complications. Arterial calcification and non-compressibility may limit test interpretation in this population. Developing tools capable of identifying PAD and predicting major adverse cardiac event (MACE) and limb event (MALE) outcomes among patients with DM would be clinically useful. Deep neural network analysis of resting Doppler arterial waveforms was used to detect PAD among patients with DM and to identify those at greatest risk for major adverse outcome events.

METHODS

Consecutive patients with DM undergoing lower limb arterial testing (April 1, 2015-December 30, 2020) were randomly allocated to training, validation, and testing subsets (60%, 20%, and 20%). Deep neural networks were trained on resting posterior tibial arterial Doppler waveforms to predict all-cause mortality, MACE, and MALE at 5 years using quartiles based on the distribution of the prediction score.

RESULTS

Among 11,384 total patients, 4211 patients with DM met study criteria (mean age, 68.6 ± 11.9 years; 32.0% female). After allocating the training and validation subsets, the final test subset included 856 patients. During follow-up, there were 262 deaths, 319 MACE, and 99 MALE. Patients in the upper quartile of prediction based on deep neural network analysis of the posterior tibial artery waveform provided independent prediction of death (hazard ratio [HR], 3.58; 95% confidence interval [CI], 2.31-5.56), MACE (HR, 2.06; 95% CI, 1.49-2.91), and MALE (HR, 13.50; 95% CI, 5.83-31.27).

CONCLUSIONS

An artificial intelligence enabled analysis of a resting Doppler arterial waveform permits identification of major adverse outcomes including all-cause mortality, MACE, and MALE among patients with DM.

Artificial Intelligence of Arterial Doppler Waveforms to Predict Major Adverse Outcomes Among Patients Evaluated for Peripheral Artery Disease

BACKGROUND

Patients with peripheral artery disease are at increased risk for major adverse cardiac events, major adverse limb events, and all-cause death. Developing tools capable of identifying those patients with peripheral artery disease at greatest risk for major adverse events is the first step for outcome prevention. This study aimed to determine whether computer-assisted analysis of a resting Doppler waveform using deep neural networks can accurately identify patients with peripheral artery disease at greatest risk for adverse outcome events.

METHODS AND RESULTS

Consecutive patients (April 1, 2015, to December 31, 2020) undergoing ankle-brachial index testing were included. Patients were randomly allocated to training, validation, and testing subsets (60%/20%/20%). Deep neural networks were trained on resting posterior tibial arterial Doppler waveforms to predict major adverse cardiac events, major adverse limb events, and all-cause death at 5 years. Patients were then analyzed in groups based on the quartiles of each prediction score in the training set. Among 11 384 total patients, 10 437 patients met study inclusion criteria (mean age, 65.8±14.8 years; 40.6% women). The test subset included 2084 patients. During 5 years of follow-up, there were 447 deaths, 585 major adverse cardiac events, and 161 MALE events. After adjusting for age, sex, and Charlson comorbidity index, deep neural network analysis of the posterior tibial artery waveform provided independent prediction of death (hazard ratio [HR], 2.44 [95% CI, 1.78-3.34]), major adverse cardiac events (HR, 1.97 [95% CI, 1.49-2.61]), and major adverse limb events (HR, 11.03 [95% CI, 5.43-22.39]) at 5 years.

CONCLUSIONS

An artificial intelligence-enabled analysis of Doppler arterial waveforms enables identification of major adverse outcomes among patients with peripheral artery disease, which may promote early adoption and adherence of risk factor modification.

Risk Stratification and Management of Intermediate-Risk Acute Pulmonary Embolism

Pulmonary embolism (PE) is the third most common cause of cardiovascular death and necessitates prompt, accurate risk assessment at initial diagnosis to guide treatment and reduce associated mortality. Intermediate-risk PE, defined as the presence of right ventricular (RV) dysfunction in the absence of hemodynamic compromise, carries a significant risk for adverse clinical outcomes and represents a unique diagnostic challenge. While small clinical trials have evaluated advanced treatment strategies beyond standard anticoagulation, such as thrombolytic or endovascular therapy, there remains continued debate on the optimal care for this patient population. Here, we review the most recent risk stratification models, highlighting differences between prediction scores and their limitations, and discuss the utility of serologic biomarkers and imaging modalities to detect right ventricular dysfunction. Additionally, we examine current treatment recommendations including anticoagulation strategies, use of thrombolytics at full and reduced doses, and utilization of invasive treatment options. Current knowledge gaps and ongoing studies are highlighted.

Comparison of Venous Thromboembolism Outcomes after COVID-19 and Influenza Vaccinations

Background  Published data on the risk of venous thromboembolism (VTE) with coronavirus disease 2019 (COVID-19) vaccines are scarce and inconclusive, leading to an unmet need for further studies. Methods  A retrospective, multicentered study of adult patients vaccinated for one of the three approved COVID-19 vaccines in the United States of America and a pre-COVID-19 cohort of patients vaccinated for influenza at two institutions: Mayo Clinic Enterprise sites and the Medical College of Wisconsin, looking at rate of VTE over 90 days. VTE was identified by applying validated natural language processing algorithms to relevant imaging studies. Kaplan-Meier curves were used to evaluate rate of VTE and Cox proportional hazard models for incident VTE after vaccinations. Sensitivity analyses were performed for age, sex, outpatient versus inpatient status, and type of COVID-19 vaccine. Results  A total of 911,381 study subjects received COVID-19 vaccine (mean age: 56.8 [standard deviation, SD: 18.3] years, 55.3% females) and 442,612 received influenza vaccine (mean age: 56.5 [SD: 18.3] years, 58.7% females). VTE occurred within 90 days in 1,498 (0.11%) of the total 1,353,993 vaccinations: 882 (0.10%) in the COVID-19 and 616 (0.14%) in the influenza vaccination cohort. After adjusting for confounding variables, there was no difference in VTE event rate after COVID-19 vaccination compared with influenza vaccination (adjusted hazard ratio: 0.95 [95% confidence interval: 0.85-1.05]). No significant difference in VTE rates was observed between the two cohorts on sensitivity analyses. Conclusion  In this large cohort of COVID-19-vaccinated patients, risk of VTE at 90 days was low and no different than a pre-COVID-19 cohort of influenza-vaccinated patients.

Comparative Effectiveness of Anticoagulants in Patients With Cancer-Associated Thrombosis

Importance

Patterns of clinical utilization and comparative effectiveness of anticoagulants for cancer-associated thrombosis (CAT) remain largely unexplored.

Objectives

To assess patterns of and factors associated with anticoagulant use and to evaluate the comparative effectiveness of contemporary anticoagulants in patients with active cancer in a clinical setting.

Design, Setting, and Participants

This retrospective cohort study obtained deidentified OptumLabs electronic health record claims data from January 1, 2012, to September 30, 2019. Adult patients (≥18 years of age) with a primary cancer diagnosis (except skin cancer) during at least 1 inpatient or 2 outpatient visits within 6 months before the venous thromboembolism (VTE) date were included. Data were analyzed from April 2020 to September 2021.

Exposures

The patients were grouped according to the anticoagulant prescribed: (1) direct oral anticoagulants (DOACs), (2) low-molecular-weight heparin (LMWH), and (3) warfarin.

Main Outcomes and Measures

Odds ratios (ORs) were used to present the association between factors of interest and utilization of anticoagulants. Main efficacy outcomes included risk of VTE recurrence and all-cause mortality. Main safety outcomes included the risk of hospitalization due to major bleeding. Relative treatment effect estimates were expressed as hazard ratios (HRs) with 95% CIs.

Results

This study included 5100 patients (mean [SD] age, 66.3 [12.3] years; 2670 [52.4%] women; 799 [15.7%] Black, 389 [7.6%] Hispanic, and 3559 [69.8%] White individuals). Overall, 2512 (49.3%), 1488 (29.2%), and 1460 (28.6%) filled prescriptions for DOACs, LMWH, and warfarin, respectively. The median (IQR) treatment duration was 3.2 (1.0-6.5) months for DOACs, 3.1 (1.0-6.8) months for warfarin, and 1.8 (0.9-3.8) months for LWMH. Patients with lung (OR, 2.07; 95% CI, 1.12-3.65), urological (OR, 1.94; 95% CI,1.08-3.49), gynecological (OR, 4.25; 95% CI, 2.31-7.82), and colorectal (OR, 2.26; 95% CI, 1.20-4.32) cancer were associated with increased prescriptions for LMWH compared with DOACs. LMWH (HR, 1.47; 95% CI, 1.14-1.90) and warfarin (HR, 1.46; 95% CI, 1.13-1.87) were associated with an increased risk of VTE recurrences compared with DOACs. LMWH was associated with an increased risk of major bleeding (HR, 2.27; 95% CI, 1.62-3.20) and higher all-cause mortality (HR, 1.61; 95% CI, 1.15-2.25) compared with DOACs.

Conclusions and Relevance

In this comparative effectiveness study of claims-based data, patients with CAT received anticoagulation for a remarkably short duration in clinical settings. DOACs was associated with a lower risk of VTE recurrence, major bleeding, and mortality. Warfarin may still be considered for patients with contraindications to DOACs and those with poor persistence on LMWH.

Venous thromboembolism after COVID-19 vaccination in patients with thrombophilia

Patients with thrombophilia remain concerned about venous thromboembolism (VTE) risk with COVID-19 vaccinations. The aim of this study was to examine VTE outcomes in patients with inherited or acquired thrombophilia who were vaccinated for COVID-19. Vaccinated patients ≥18 years between November 1, 2020 and November 1, 2021 were analyzed using electronic medical records across the Mayo Clinic enterprise. The primary outcome was imaging confirmed acute VTE occurring 90 days before and after the date of the first vaccine dose. Thrombophilia patients were identified through laboratory testing results and ICD-10 codes. A total of 792 010 patients with at least one COVID-19 vaccination were identified. Six thousand sixty-seven of these patients were found to have a thrombophilia, among whom there was a total of 39 VTE events after compared to 51 VTE events before vaccination (0.64% vs. 0.84%, p = .20). In patients with Factor V Leiden or prothrombin gene mutation, VTE occurred in 27 patients before and in 29 patients after vaccination (0.61 vs. 0.65%, p = .79). In patients with antiphospholipid syndrome, VTE occurred in six patients before and four patients after vaccination (0.59% vs. 0.39%, p = .40). No difference was observed in the overall VTE rate when comparing the postvaccination 90 days to the prevaccination 90 days, adjusted hazard ratio 0.81 (95% confidence interval: 0.53-1.23). In this subgroup of COVID-19 vaccinated patients with thrombophilia, there was no increased risk for acute VTE postvaccination compared to the prevaccination timeframe. These results are consistent with prior studies and should offer additional reassurance to patients with inherited or acquired thrombophilia.

Influence of primary cancer site on clinical outcomes of anticoagulation for associated venous thromboembolism

INTRODUCTION

The outcome of anticoagulation for cancer-associated venous thromboembolism (Ca-VTE) differs according to cancer location, but data are limited and inconsistent.

MATERIALS AND METHODS

Patients with acute venous thromboembolism (VTE) enrolled between 03/01/2013 and 04/30/2021 were followed prospectively to assess VTE recurrence, major bleeding (MB), clinically relevant non-major bleeding (CRNMB), and death.

RESULTS

There were 1702 (45.3 %) patients with Ca-VTE including: gastrointestinal (n = 340), pancreatic (n = 223), hematologic (n = 188), genitourinary (n = 163), lung (n = 139), ovarian (n = 109), breast (n = 97), renal (n = 75), prostate (n = 73), hepatobiliary (n = 70), brain (n = 57), and other cancers (n = 168); 2057 VTE patients had no cancer (NoCa-VTE). Hepatobiliary cancer had the highest VTE recurrence (all rates 100 person-years) of all cancers and higher compared to NoCa-VTE (13.69, p = 0.01), while the MB rate, although numerically higher (15.91), was not different (p = 0.09). Another 3 cancers had higher VTE recurrence but similar MB rates compared to NoCa-VTE: genitourinary [(9.59, p = 0.01) and (7.03, p = 1.0)], pancreatic [(9.74, p < 0.001) and (5.47, p = 1.00)], and hematologic [(5.29, p = 0.05) and (3.59, p = 1.0)]. Renal cancer had the highest rate of MB among all cancers and was higher than that of NoCa-VTE (16.49; p < 0.001), with no difference in VTE recurrence (1.62; p = 1.0). VTE recurrence and MB rates were not significantly different between NoCa-VTE and gastrointestinal, lung, breast, prostate, and brain cancers. CRNMB rates were similar and mortality higher in Ca-VTE patients, except for prostate and breast cancer, compared to NoCa-VTE.

CONCLUSIONS

Significant differences in clinical outcomes indicate that anticoagulation strategies may need to be tailored to the primary cancer location.

Evaluation of Direct Oral Anticoagulant Reversal Agents in Intracranial Hemorrhage: A Systematic Review and Meta-analysis

IMPORTANCE

Direct oral anticoagulant (DOAC)-associated intracranial hemorrhage (ICH) has high morbidity and mortality. The safety and outcome data of DOAC reversal agents in ICH are limited.

OBJECTIVE

To evaluate the safety and outcomes of DOAC reversal agents among patients with ICH.

DATA SOURCES

PubMed, MEDLINE, The Cochrane Library, Embase, EBSCO, Web of Science, and CINAHL databases were searched from inception through April 29, 2022.

STUDY SELECTION

The eligibility criteria were (1) adult patients (age ≥18 years) with ICH receiving treatment with a DOAC, (2) reversal of DOAC, and (3) reported safety and anticoagulation reversal outcomes. All nonhuman studies and case reports, studies evaluating patients with ischemic stroke requiring anticoagulation reversal or different dosing regimens of DOAC reversal agents, and mixed study groups with DOAC and warfarin were excluded.

DATA EXTRACTION AND SYNTHESIS

Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were used for abstracting data and assessing data quality and validity. Two reviewers independently selected the studies and abstracted data. Data were pooled using the random-effects model.

MAIN OUTCOMES AND MEASURES

The primary outcome was proportion with anticoagulation reversed. The primary safety end points were all-cause mortality and thromboembolic events after the reversal agent.

RESULTS

A total of 36 studies met criteria for inclusion, with a total of 1832 patients (967 receiving 4-factor prothrombin complex concentrate [4F-PCC]; 525, andexanet alfa [AA]; 340, idarucizumab). The mean age was 76 (range, 68-83) years, and 57% were men. For 4F-PCC, anticoagulation reversal was 77% (95% CI, 72%-82%; I2 = 55%); all-cause mortality, 26% (95% CI, 20%-32%; I2 = 68%), and thromboembolic events, 8% (95% CI, 5%-12%; I2 = 41%). For AA, anticoagulation reversal was 75% (95% CI, 67%-81%; I2 = 48%); all-cause mortality, 24% (95% CI, 16%-34%; I2 = 73%), and thromboembolic events, 14% (95% CI, 10%-19%; I2 = 16%). Idarucizumab for reversal of dabigatran had an anticoagulation reversal rate of 82% (95% CI, 55%-95%; I2 = 41%), all-cause mortality, 11% (95% CI, 8%-15%, I2 = 0%), and thromboembolic events, 5% (95% CI, 3%-8%; I2 = 0%). A direct retrospective comparison of 4F-PCC and AA showed no differences in anticoagulation reversal, proportional mortality, or thromboembolic events.

CONCLUSIONS AND RELEVANCE

In the absence of randomized clinical comparison trials, the overall anticoagulation reversal, mortality, and thromboembolic event rates in this systematic review and meta-analysis appeared similar among available DOAC reversal agents for managing ICH. Cost, institutional formulary status, and availability may restrict reversal agent choice, particularly in small community hospitals.

Incidental pulmonary embolism in cancer and noncancer patients: Prospective cohort study

BACKGROUND

Clinical picture and outcome of incidental pulmonary embolism (iPE) compared to symptomatic pulmonary embolism (sPE) remain unclear.

METHODS

Demographics, recurrent venous thromboembolism (VTE), mortality, major bleeding, and clinically relevant nonmajor bleeding (CRNMB) were compared between iPE and sPE patients who were followed prospectively at Mayo Thrombophilia Clinic (March 1, 2013 to August 1, 2020).

RESULTS

Out of 3576 VTE patients, 1417 (39.6%) had PE: 562 (39.7%) iPE and 855 sPE. Patients with cancer were more likely to have iPE (400 iPE vs. 314 sPE) compared to those without cancer (162 iPE vs. 541 sPE). VTE recurrence rate (all per 100 person-years) was similar in all iPE and sPE patients (3.34 vs. 3.68, p = .50), with cancer (4.16 vs. 4.89, p = .370), and without cancer patients (0.89 vs. 2.80, p = .25). Higher mortality observed in all patients with iPE compared to sPE (46.45 vs. 23.47, p < .001) and with cancer (56.41 vs. 45.77, p = .03) became not significant after adjustment for age, antiplatelet therapy, metastases, and cancer location. Noncancer iPE patients had higher mortality (15.95 vs. 7.18, p = .006) even after adjustment (p = .05). The major bleeding rate was also higher in all patients iPE compared to sPE (7.10 vs. 3.68, p = .03), but not after adjustment (p = .974); higher major bleeding rate in noncancer patients (6.49 vs. 1.25, p = .007) remained significant after adjustment (.02). CRNMB rate was similar to iPE and sPE patients.

CONCLUSION

iPE represents a more serious clinical condition compared to sPE as indicated by the higher mortality and major bleeding but these differences reflect underlying comorbidities rather than the seriousness of the embolic event.

Risk of venous thromboembolism after COVID-19 vaccination

BACKGROUND

COVID-19 vaccinations in the United States are effective in preventing illness and hospitalization yet concern over post-vaccination venous thromboembolism (VTE) risk has led to vaccine hesitancy.

METHODS

The aim of this study was to compare VTE rates before and after COVID-19 vaccination. COVID-19 vaccinated patients ≥18 years between November 1, 2020 through November 1, 2021 were analyzed using electronic medical records across the Mayo Clinic enterprise. The primary outcome was imaging confirmed acute VTE (upper or lower deep vein thrombosis or pulmonary embolism) occurring 90 days before and after the date of first vaccine dose.

RESULTS

A total of 792 010 patients with at least one COVID-19 vaccination were identified (Pfizer, n = 452 950, Moderna, n = 290 607, and Janssen [Johnson & Johnson], n = 48 453). A total of 1565 VTE events occurred in the 90 days before (n = 772) and after (n = 793) COVID-19 vaccination. VTE post-vaccination occurred in 326 patients receiving Moderna (0.11%, incidence rate [IR] 4.58 per 1000p-years), 425 patients receiving Pfizer (0.09%, IR 3.84 per 1000p-years), and 42 receiving Janssen (0.09%, IR 3.56 per 1000p-years). Compared to the pre-vaccination timeframe, the adjusted hazard ratio (aHR) for VTE after the Janssen vaccination was 0.97 (95% confidence interval [CI] 0.63-1.50), aHR 1.02 (95% CI 0.87-1.19) for Moderna, and aHR 1.00 (95% CI 0.87-1.15) for Pfizer.

CONCLUSION

In this large cohort of COVID-19 vaccinated patients, no increased risk for acute VTE post-vaccination was identified for the authorized vaccines in the United States.

Real-world utilization and comparative effectiveness of treatment options in cancer-associated thrombosis: A propensity score weighed analysis

6589

Background: Real-world utilization and comparative effectiveness of direct oral anticoagulants (DOACs), low molecular weight heparin (LMWH) and warfarin for cancer-associated venous thromboembolism (VTE) treatment remains largely unexplored. Methods: De-identified administrative claims data (OptumLabs - Data Warehouse) for adult active cancer patients with acute VTE (1/1/2012-9/30/2019) were assessed for utilization patterns, recurrent VTE, and major bleeding differences between DOACs, LMWH, and warfarin. Patients were followed up till the end of treatment. Patients who crossed over to other anti-coagulants within the follow up period were excluded. Multinomial logistic regression was used to assess predictors of anticoagulant administration. Kaplan-Meier curves were used to evaluate the differences in time to medication discontinuation among the three groups. Propensity score (PS) and inverse probability of treatment weighting were used to balance baseline differences between groups. Standardized difference (SD) was used to assess the balance of covariates after weighting and SD < 10% was considered acceptable. Weighted Cox proportional hazards regression with a robust variance estimator was then used to assess outcomes in PS weighted groups. Results: A total of 5100 patients met the inclusion criteria; 49.3% filled DOACs (n = 2512), 29.2% LMWH (n = 1488), and 28.6% warfarin (n = 1460). Median treatment duration was around 3.2 months for DOACs and warfarin, and 1.8 months for LWMH ( P-value < 0.01). Multinomial regression analysis showed that younger patients were more likely to be prescribed LMWH (OR 0.97 95% CI: 0.97-0.98) as compared to DOACs. Patients with lung (OR 2.07 95% CI: 1.12-3.65; OR 1.87 95% CI: 1.04-3.37), urological (OR: 1.94 95% CI:1.08-3.49; OR: 2.04 95% CI: 1.12-3.73), gynecological (OR 4.25, 95% CI: 2.31-7.82; OR 2.31 95% CI: 1.22-4.39) and colorectal cancer (OR 2.26 95% CI: 1.20-4.32; OR 2.51; 95% CI: 1.32-4.79) were more likely to be prescribed LMWH or warfarin respectively, compared to DOACs. VTE recurrences were more frequent for patients receiving LMWH (HR: 1.47; 95% CI: 1.14-1.90) or warfarin (HR: 1.46; 95% CI: 1.13-1.87) compared to DOACs. LMWH, but not warfarin, was associated with greater major bleeding rates compared to DOACs (HR: 2.27; 95% CI: 1.62-3.20). All-cause mortality rates were also significantly higher for patients receiving LMWH, but not warfarin compared to DOACs (HR: 1.61; 95% CI: 1.15-2.25). Conclusions: Patients with cancer associated VTE remain on anti-coagulation for a remarkably short duration in real-world clinical practice. DOACs and warfarin may offer better compliance than LMWH. Patients receiving DOACs have a lower risk of VTE recurrence, less major bleeding, and improved mortality. Warfarin may still be considered for patients with contraindications to DOACs and non-compliant to LMWH.

Artificial intelligence for the evaluation of peripheral artery disease using arterial Doppler waveforms to predict abnormal ankle-brachial index

BACKGROUND

Patients with peripheral artery disease (PAD) are at increased risk for major adverse limb and cardiac events including mortality. Developing screening tools capable of accurate PAD identification is a necessary first step for strategies of adverse outcome prevention. This study aimed to determine whether machine analysis of a resting Doppler waveform using deep neural networks can accurately identify patients with PAD.

METHODS

Consecutive patients (4/1/2015 - 12/31/2020) undergoing rest and postexercise ankle-brachial index (ABI) testing were included. Patients were randomly allocated to training, validation, and testing subsets (70%/15%/15%). Deep neural networks were trained on resting posterior tibial arterial Doppler waveforms to predict normal (> 0.9) or PAD (⩽ 0.9) using rest and postexercise ABI. A separate dataset of 151 patients who underwent testing during a period after the model had been created and validated (1/1/2021 - 3/31/2021) was used for secondary validation. Area under the receiver operating characteristic curves (AUC) were constructed to evaluate test performance.

RESULTS

Among 11,748 total patients, 3432 patients met study criteria: 1941 with PAD (mean age 69 ± 12 years) and 1491 without PAD (64 ± 14 years). The predictive model with highest performance identified PAD with an AUC 0.94 (CI = 0.92-0.96), sensitivity 0.83, specificity 0.88, accuracy 0.85, and positive predictive value (PPV) 0.90. Results were similar for the validation dataset: AUC 0.94 (CI = 0.91-0.98), sensitivity 0.91, specificity 0.85, accuracy 0.89, and PPV 0.89 (postexercise ABI comparison).

CONCLUSION

An artificial intelligence-enabled analysis of a resting Doppler arterial waveform permits identification of PAD at a clinically relevant performance level.

Evaluation of soluble fibrin monomer complex in patients in SARS-CoV-2 COVID-19 infection-associated coagulopathy

Hospitalized patients with COVID-19 infection frequently have coagulopathy resembling disseminated intravascular coagulation (DIC). An elevation of D-dimer level is associated with a poor prognosis; however, the role of other fibrin degradation products, such as soluble fibrin monomers (SFMC), is not known. The objective of the study was to investigate the frequency and prognostic role of elevated SFMC in patients with COVID-19. In this retrospective cohort study, patients hospitalized between April 1, 2020 and December 14, 2020 at Mayo Clinic with COVID-19 infection who underwent DIC panel testing were identified. Results of laboratory tests and outcomes (thrombosis and death) within 40 days of testing were obtained via medical record review. Of 108 patients, D-dimer was elevated in 82 (75.9%) patients. Of those with elevated D-dimer, SFMC was elevated in 19/82 (23%) patients. There were 16 thrombotic events and 16 deaths during the 40-day follow-up. The incidence of overt-DIC was 4.6%. In univariate analysis, D-dimer ≥5 x highest upper limit normal (ULN) and elevated SFMC were each associated with higher 40-day mortality. However, when used in combination with D-dimer ≥5 x highest ULN, an elevated SFMC provided no further mortality predictive value. Compared to 75.9% of patients with elevated D-dimers, of those tested, only 23% had elevated SFMC. These results support the hypothesis that elevated D-dimer in COVID-19 infection is a direct consequence of endothelial damage and not overt-DIC.

Pulmonary artery capacitance and pulmonary vascular resistance as prognostic indicators in acute pulmonary embolism

Aims

The non-invasive calculation of right ventricular (RV) haemodynamics as pulmonary artery (PA) capacitance (PAC) and pulmonary vascular resistance (PVR) have proved to be feasible, easy to perform, and of high prognostic value. We, therefore, evaluated whether baseline PAC and PVR could predict clinical outcomes for patients with acute pulmonary embolism (PE).

Methods and results

We prospectively followed 373 patients [mean (standard deviation) age, 64.1 (14.9) years; 58.4% were men, and 27.9% had cancer] who had acute PE and transthoracic echocardiography within 1 day of diagnosis from 1 March 2013 through 30 June 2020. Pulmonary artery capacitance was calculated as left ventricular stroke volume/(PA systolic pressure − PA diastolic pressure). Pulmonary vascular resistance was calculated as (tricuspid regurgitant velocity/RV outflow tract velocity time integral) × 10 + 0.16. These two variables were calculated retrospectively from the values obtained with transthoracic echocardiography. Pulmonary artery capacitance was acquired in 99 (27%) patients and PVR in 65 (17%) patients. Univariable and bivariable logistic regression analyses, and receiver operating characteristic curves were used to evaluate the ability of these haemodynamic measurements to predict mortality up to 6 months. After using bivariable models to adjust individually for age, cancer, and pulmonary hypertension. Pulmonary vascular resistance was associated with all-cause mortality at 3 months [area under the curve (AUC) 0.75, 95% confidence interval (CI) 0.61–0.86; P = 0.01], and 6 months (AUC 0.81; 95% CI 0.69–0.91; P≤ 0.03). Pulmonary artery capacitance was associated with all-cause mortality at 30 days (AUC 0.95; 95% CI 0.82–0.99; P &lt; 0.001) and 3 months (AUC 0.84; 95% CI 0.65–0.99; P = 0.003).

Conclusion

Non-invasive measurement of RV haemodynamics could provide prognostic information of patients with acute PE. Pulmonary artery capacitance and PVR are potentially important predictors of all-cause mortality in these patients and should be explored in future studies.

Single versus multiple and incidental versus symptomatic subsegmental pulmonary embolism: clinical characteristics and outcome

It remains unexplored if the clinical picture and outcome of subsegmental pulmonary embolism (SSPE) differ between single versus multiple, and incidental versus symptomatic embolism. Consecutive patients anticoagulated for SSPE at the Mayo Thrombophilia Clinic (03/01/2013-12/31/2020) were followed forward to assess venous thromboembolism (VTE) recurrence, mortality, major bleeding, and clinically relevant non-major bleeding (CRNMB); expressed as a rate per 100 person-years. Among 3878 VTE patients, 1541 had pulmonary embolism including 224 (14.6%) with SSPE either single (n = 139) or multiple (n = 85; 46 bilateral and 39 unilateral emboli); 134 had incidental and 90 symptomatic SSPE. Patients with single were less often symptomatic and less often had coexisting DVT than multiple SSPE. Patients with incidental had a two-fold higher frequency of cancer compared to symptomatic SSPE. During the study period, 1 patient with single and 2 with multiple SSPE had VTE recurrence (rate of 1.14 vs 3.63, p = 0.280). Single SSPE patients experienced 2 episodes of major bleeding (rate of 2.36) while the multiple SSPE group had no major bleeding. Seven patients in each group had CRNMB events (rate of 8.20 vs 13.58 for single and multiple SSPE, respectively, p = 0.282). Patients with single SSPE had a higher death rate compared to multiple SSPE (43.07 vs 22.22, p = 0.031) but no difference was noted after adjusting for cancer (p = 0.388). Also, incidental had similar clinical outcomes to symptomatic SSPE.Interpretation Anticoagulated SSPE patients with single and multiple as well as incidental and symptomatic have a different clinical profile but similar clinical outcomes.

Timing of venous thromboembolism diagnosis in hospitalized and non-hospitalized patients with COVID-19

BACKGROUND

The reported incidence of venous thromboembolism (VTE) in COVID-19 patients varies widely depending on patient populations sampled and has been predominately studied in hospitalized patients. The goal of this study was to assess the evolving burden of COVID-19 and the timing of associated VTE events in a systems-wide cohort.

METHODS

COVID-19 PCR positive hospitalized and non-hospitalized patients ≥18 years of age tested between 1/1/2020 through 12/31/2020 were retrospectively analyzed using electronic medical records from multiple states across the Mayo Clinic enterprise. Radiology reports within 90 days before and after confirmed COVID-19 diagnosis were examined for VTE outcomes using validated Natural Language Processing (NLP) algorithms.

RESULTS

A 29-fold increased rate of VTE compared to the pre-COVID-19 period was noted during the first week following the first positive COVID-19 test (RR: 29.39; 95% CI 21.77-40.03). The rate of VTE steadily decreased and returned to baseline by the 6th week. Among 366 VTE events, most occurred during (n = 243, 66.3%) or after (n = 111, 30.3%) initial hospitalization. Only 11 VTE events were identified in patients who did not require hospitalization (3.0% of total VTE events). VTE and mortality increased with advancing age with a pronounced increased each decade in older patients.

CONCLUSION

We observed a profoundly increased risk of VTE within the first week after positive testing for COVID-19 that returned to baseline levels after 6 weeks. VTE events occurred almost exclusively in patients who were hospitalized, with the majority of VTE events identified within the first days of hospitalization.

Bleeding in Patients With Gastrointestinal Cancer Compared With Nongastrointestinal Cancer Treated With Apixaban, Rivaroxaban, or Enoxaparin for Acute Venous Thromboembolism

OBJECTIVE

To compare the bleeding risk in patients with gastrointestinal (GI) cancer with that in patients with non-GI cancer treated with anticoagulation for acute cancer-associated venous thromboembolism (Ca-VTE).

PATIENTS AND METHODS

Consecutive patients with Ca-VTE seen at the Mayo Thrombophilia Clinic between March 1, 2013, and April 20, 2020, were observed prospectively to assess major bleeding and clinically relevant nonmajor bleeding (CRNMB).

RESULTS

In the group of 1392 patients with Ca-VTE, 499 (35.8%) had GI cancer including 272 with luminal GI cancer (lower GI, 208; upper GI, 64), 176 with pancreatic cancer, and 51 with hepatobiliary cancer. The rate of major bleeding and CRNMB in patients with GI cancer was similar to that in 893 (64.2%) patients with non-GI cancer treated with apixaban, rivaroxaban, or enoxaparin. Apixaban had a higher rate of major bleeding in luminal GI cancer compared with the non-GI cancer group (15.59 vs 3.26 per 100 person-years; P=.004) and compared with enoxaparin in patients with luminal GI cancer (15.59 vs 3.17; P=.04). Apixaban had a lower rate of CRNMB compared with rivaroxaban in patients with GI cancer (3.83 vs 9.40 per 100 person-years; P=.03). Patients treated with rivaroxaban in the luminal GI cancer group had a major bleeding rate similar to that of patients with non-GI cancer (2.04 vs 4.91 per 100 person-years; P=.37).

CONCLUSION

Apixaban has a higher rate of major bleeding in patients with luminal GI cancer compared with patients with non-GI cancer and compared with enoxaparin in patients with luminal GI cancer. Rivaroxaban shows no increased risk of major bleeding in patients with GI cancer or luminal GI cancer compared with patients with non-GI cancer.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03504007.

Pulmonary artery capacitance a simple and novel prognostic variable in acute pulmonary embolism

Background

The non-invasive calculation of right ventricular hemodynamics such as the pulmonary artery capacitance (PAC) has proven to be feasible and easy to perform. The simplified pulmonary embolism severity index (sPESI) and pulmonary vascular resistance (PVR) are other prognostic tools that have been used in the past.

Purpose

To evaluate if baseline PAC can outperform PVR and sPESI to predict all-cause short-term mortality in patients with acute pulmonary embolism (PE).

Methods

373 patients with acute PE and a transthoracic echocardiogram performed within one day of diagnosis from March 2013 through June 2020 were followed prospectively. PAC was calculated as: Left ventricular stroke volume/ (Pulmonary artery systolic pressure – Pulmonary artery diastolic pressure). PVR was calculated as: Tricuspid regurgitant velocity / Right ventricular outflow tract velocity time integral x 10 + 0.16. The sPESI was used to evaluate prognosis by categorizing patients into low and high-risk categories. Multiple logistic regression analyses and receiver-operating characteristic curves were used to evaluate the ability of PAC, PVR, and sPESI to predict all-cause mortality up to six months. The Youden index was used to determine the cut-off value with the highest sensitivity and specificity. Kaplan–Meier curves were performed to determine event-free survival rate, differences between groups were assessed using the Wilcoxon Test.

Results

Mean age was 64±15 years (58% male, 28% cancer). PAC was associated with mortality at thirty days (p 0.0003), three months (p 0.003), and six months (p 0.011) (Table). PVR was associated with mortality at thirty days, three months, and six months (p 0.045, 0.012, and 0.031 respectively). The sPESI score ≥1 (high risk) was associated with all-cause mortality at three months and six months (p 0.0136 and &lt;0.0001 respectively). PAC was the strongest predictor of all-cause mortality with an AUC of 0.95 (CI 0.82- 0.99) at thirty days, 0.84 (CI 0.65–0.99) at three months, and 0.77 (CI 0.57–0.96) for six months. Corresponding Kaplan-Meier survival curve of PAC and thirty days all-cause mortality is presented in the Figure. PVR had an AUC of 0.75 (CI 0.48–0.95) at thirty days, 0.79 (CI 0.58–0.94) at three months, and 0.72 (CI 0.50–0.90) at six months. The sPESI had an AUC of 0.62 (CI 0.54–0.66) at three months and 0.64 (CI 0.59–0.67) at six months.

Conclusion

In patients with acute PE, PAC outperforms sPESI and PVR as a predictor of short-term all-cause mortality at thirty days, three months, and six months. These three variables should be explored head to head prospectively for their utility to predict short term all-cause mortality.

Funding Acknowledgement

Type of funding sources: None.

Peripheral Blood Cytopenia and Risk of Cardiovascular Disease and Mortality

Background

Individual blood cell count abnormalities have been associated with cardiovascular disease and increased mortality. In this study, we defined a “cytopenia phenotype,” reflecting bone marrow hypoproliferation, to determine if peripheral blood cytopenia is associated with increased cardiovascular disease and mortality risk.

Methods and Results

Study participants were derived from a biracial observational cohort study, REGARDS (Reasons for Geographic and Racial Differences in Stroke), that enrolled 30 239 Black and White participants aged ≥45 years between 2003 and 2007. Median follow up was ≈9 years. The current study included 19 864 participants from REGARDS study (37.9% men, 40% Black participants) who have complete blood count available at study enrollment. We defined a cytopenia phenotype based on age‐, sex‐, and race‐adjusted lowest fifth percentile of blood counts. Multivariable Cox proportional hazards models estimated the hazard ratios (HR) and 95% CI of cytopenia for mortality and incident cardiovascular disease in adjusted models. Mean age of the study participants was 64 years (SD:9.7). The prevalence of cytopenia was 1.9% (n=378). Cytopenia was associated with increased risk of all‐cause mortality (HR, 1.73; 95% CI, 1.34–2.22) and cardiovascular disease mortality (HR, 1.56; 95% CI, 1.11–2.29). Cytopenia was associated with stroke risk in Black but not White participants (HR, 1.96 versus 0.86; P‐interaction for race=0.08) and was not associated with coronary heart disease risk.

Conclusions

We defined a cytopenia phenotype with clinical implications for mortality and stroke risk in a large biracial and geographically diverse population. Whether generated through somatic mutations or decreased organ function, cytopenia was associated with mortality risk and was a race‐specific risk factor for stroke.

Evaluation of Changing Vena Cava Filter Use and Inpatient Hospital Mortality from 2016-2019: A Single-Institution Quality Improvement Project

Objective

To evaluate the changing trends of vena cava filter (VCF) insertion and determine whether changes in VCF use affected inpatient mortality.

Patients and Methods

A quality improvement project at Mayo Clinic, Rochester, Minnesota, tracks the type and reason for VCF insertions from January 1, 2016, through December 31, 2019, to facilitate appropriate retrieval. The rate of VCF insertions was compared with inpatient mortality rates, normalized for patient volumes using the number of hospital inpatient discharges.

Results

A total of 698 VCFs were placed in 695 patients: 2016 (n=243), 2017 (n=156), 2018 (n=156), and 2019 (n=120). The rate of VCF insertions (per 1000 inpatient discharges) was 4.02 in 2016, 2.91 in 2017, 2.54 in 2018, and 1.93 in 2019. Mean ± SD age at placement was 62±16.4 years and 59.2% (413/698) were men. Most VCFs were retrievable (85.1%; 594/698) and were placed for treatment (78.4%; 547/698) indications (acute venous thromboembolism within 3 months). The rate of VCF insertions was compared with the inpatient mortality rate (per 100 inpatient discharges) and remained stable (1.83 in 2016, 1.79 in 2017, 1.83 in 2018, and 1.76 in 2019) despite the significant decline in VCF use.

Conclusion

Data from this quality improvement study demonstrate a reduction of more than 50% in the use of VCFs from 2016 through 2019 at a large academic hospital. These changes are difficult to attribute to any single change in clinical use and there was no appreciable increase in the inpatient hospital mortality rate associated with this decrease in VCF filter use.

Macrovascular Thrombotic Events in a Mayo Clinic Enterprise-Wide Sample of Hospitalized COVID-19-Positive Compared With COVID-19-Negative Patients

OBJECTIVE

To determine the difference in the rate of thromboembolic complications between hospitalized coronavirus disease 2019 (COVID-19)-positive compared with COVID-19-negative patients.

PATIENTS AND METHODS

Adult patients hospitalized from January 1, 2020, through May 8, 2020, who had COVID-19 testing by polymerase chain reaction assay were identified through electronic health records across multiple hospitals in the Mayo Clinic enterprise. Thrombotic outcomes (venous and arterial) were identified from the hospital problem list.

RESULTS

We identified 3790 hospitalized patients with COVID-19 testing across 19 hospitals, 102 of whom had positive test results. The median age was lower in the COVID-positive patients (62 vs 67 years; P=.03). The median duration of hospitalization was longer in COVID-positive patients (8.5 vs 4 days; P<.001) and more required intensive care unit care (56.9% [58 of 102] vs 26.8% [987 of 3688]; P<.001). Comorbidities, including atrial fibrillation/flutter, heart failure, chronic kidney disease, and malignancy, were observed less frequently with COVID-positive admissions. Any venous thromboembolism was identified in 2.9% of COVID-positive patients (3 of 102) and 4.6% of COVID-negative patients (168 of 3688). The frequency of venous and arterial events was not different between the groups. The unadjusted odds ratio (OR) for COVID-positive-patients for any venous thromboembolism was 0.63 (95% CI, 0.19 to 2.02). A multivariable logistic regression model evaluated death within 30 days of hospital discharge; neither COVID positivity (adjusted OR, 1.12; 95% CI, 0.54 to 2.34) nor thromboembolism (adjusted OR, 0.90; 95% CI, 0.60 to 1.32) was associated with death.

CONCLUSION

Early experience in patients with COVID-19 across multiple academic and regional hospitals representing different US regions demonstrates a lower than previously reported incidence of thrombotic events. This incidence was not higher than a contemporary COVID-negative hospitalized comparator.

Delayed anticoagulation in venous thromboembolism: Reasons and associated outcomes

Objective

We assessed the number of cases with delayed anticoagulation initiation, explored the reasons for the delay, and its impact on outcome in patients with acute venous thromboembolism (VTE) treated in an organized setting of treatment initiation and continuous, prospective follow‐up.

Methods

Patients with anticoagulation initiation delay >24 hours were identified within the cohort of patients with acute VTE enrolled in the Mayo Clinic Venous Thromboembolism Registry between 2013 and 2020. The reasons for treatment delay were explored by reviewing the electronic database. VTE recurrence, all‐cause mortality, major bleeding, and clinically relevant nonmajor bleeding (CRNMB) were compared to those with no anticoagulation delay.

Results

Of 2378 patients with acute VTE, 100 (4.2%) experienced an anticoagulation delay. We identified seven reasons for treatment delays: deferring anticoagulation initiation to specialists (n = 38), thrombocytopenia (n = 10), planned or recent procedure (n = 16), active or recent bleeding (n = 12), missed diagnosis (n = 7), logistics (n = 6), and patient decision (n = 4). In seven cases, no reason was identified. We identified modifiable reasons for anticoagulation delay in 55%. At 90‐day follow‐up, patients with anticoagulation delay had a higher rate of mortality and major bleeding. VTE recurrence and CRNMB were not statistically different compared to those without anticoagulation delay. After adjustment for age, weight, and cancer, hazard ratios (HRs) for VTE recurrence and major bleeding remained elevated but not to a statistically significant level.

Conclusion

In the setting of a highly organized system of anticoagulation initiation, the incidence of treatment delay is low. Yet most delays could be avoided. A low number of cases provide insufficient power to evaluate the clinical consequences of anticoagulation initiation delay; however, elevated HR for VTE recurrence and major bleeding suggest association and need for further investigation.

Treatment of catheter-related thrombosis in patients with hematologic malignancies: A Venous thromboEmbolism Network U.S. retrospective cohort study

INTRODUCTION

Optimal treatment of catheter-related thrombosis (CRT) is uncertain in patients with hematologic malignancy. We aimed to evaluate the treatment strategies, outcomes, and predictors of recurrent venous thromboembolism (VTE) associated with catheter-related thrombosis (CRT) in patients with hematologic malignancy.

METHODS

We performed a multicenter retrospective cohort study of eight institutions through the Venous thromboEmbolism Network US. Patients with hematologic malignancies with documented CRT were identified using ICD-9 and ICD-10 diagnostic codes. Semi-competing risks proportional hazard regression models were created.

RESULTS AND CONCLUSIONS

Of the 663 patients in the cohort, 124 (19%) were treated with anticoagulation alone, 388 (58%) were treated with anticoagulation and catheter removal, 119 (18%) treated with catheter removal only, and 32 (5%) had neither catheter removal nor anticoagulation. 100 (15%) patients experienced a recurrent VTE event. In the 579 patients who had catheter removal, the most common reason for catheter removal was the CRT [392 (68%)]. For subjects who received any anticoagulation (n = 512), total anticoagulation duration was not associated with VTE recurrence [1.000 (0.999-1.002)]. After adjustment patients treated with catheter removal only had an increased risk of VTE recurrence [2.50 (1.24-5.07)] and death [4.96 (2.47-9.97)]. Patients with no treatment had increased risk of death [16.81 (6.22-45.38)] and death after VTE recurrence [27.29 (3.13-238.13)]. In this large, multicenter retrospective cohort, we found significant variability in the treatment of CRT in patients with hematologic malignancy. Treatment without anticoagulation was associated with recurrent VTE.

Prophylactic placement of inferior vena cava filters and the risk of death or venous thromboembolism in severe trauma patients: a retrospective study comparing two hospitals with different approaches

Background

Prophylactic use of inferior vena cava filters to prevent pulmonary embolism in trauma is controversial. The practice varies between hospitals and countries, in part due to conflicting evidence and guidelines.

Purpose

To compare the effects of pulmonary embolism, deep venous thrombosis and mortality in two hospitals using prophylactic inferior vena cava filter placement or prophylactic anticoagulation alone.

Material and Methods

Patients presenting with severe trauma were recruited from two level-1 trauma centres between January 2008 and December 2013. Recruited patients from an US hospital having prophylactic inferior vena cava filter inserted were compared to a Scandinavian hospital using prophylactic anticoagulation alone. Inclusion criteria were age >15 years, Injury Severity Score >15 and survival >24 h after hospital admission. Patients with venous thromboembolism diagnosed prior to inferior vena cava filter placement were excluded. A Cox proportional hazard regression model was used with adjustment for immortal time bias and predictor variables.

Results

In total, 951 patients were reviewed, 282 from an US hospital having inferior vena cava filters placed and 669 from a Scandinavian hospital without inferior vena cava filters. The mean age was 45.9 vs. 47.4 years and the mean Injury Severity Score was 29.8 vs. 25.9, respectively. Inferior vena cava filter placement was not associated with the hazard of pulmonary embolism (Hazard ratio=0.43; 95% confidence interval (CI) 0.12, 1.45; P=0.17) or mortality (Hazard ratio=1.16; 95% CI 0.70, 1.95; P=0.56). However, an increased rate of deep venous thrombosis was observed with inferior vena cava filters in place (Hazard ratio=3.75; 95% CI 1.68, 8.36; P=0.001).

Conclusion

In severely injured trauma patients, prophylactic inferior vena cava filter placement was not associated with pulmonary embolism or mortality. However, inferior vena cava filters were associated with increased rate of deep venous thrombosis.

Thromboinflammatory Biomarkers in COVID-19: Systematic Review and Meta-analysis of 17,052 Patients

Objective

To evaluate differences in thromboinflammatory biomarkers between patients with severe coronavirus disease 2019 (COVID-19) infection/death and mild infection.

Patients and Methods

MEDLINE, Cochrane Central Register of Controlled Trials, EMBASE, EBSCO, Web of Science, and CINAHL databases were searched for studies comparing thromboinflammatory biomarkers in COVID-19 among patients with severe COVID-19 disease or death (severe/nonsurvivors) and those with nonsevere disease or survivors (nonsevere/survivors) from January 1, 2020, through July 11, 2020. Inclusion criteria were (1) hospitalized patients 18 years or older comparing severe/nonsurvivors vs nonsevere/survivors and (2) biomarkers of inflammation and/or thrombosis. A random-effects model was used to estimate the weighted mean difference (WMD) between the 2 groups of COVID-19 severity.

Results

We included 75 studies with 17,052 patients. The severe/nonsurvivor group was older, had a greater proportion of men, and had a higher prevalence of hypertension, diabetes, cardiac or cerebrovascular disease, chronic kidney disease, malignancy, and chronic obstructive pulmonary disease. Thromboinflammatory biomarkers were significantly higher in patients with severe disease, including D-dimer (WMD, 0.60; 95% CI, 0.49 to 0.71; I²=83.85%), fibrinogen (WMD, 0.42; 95% CI, 0.18 to 0.67; I²=61.88%; P<.001), C-reactive protein (CRP) (WMD, 35.74; 95% CI, 30.16 to 41.31; I²=85.27%), high-sensitivity CRP (WMD, 62.68; 95% CI, 45.27 to 80.09; I²=0%), interleukin 6 (WMD, 22.81; 95% CI, 17.90 to 27.72; I²=90.42%), and ferritin (WMD, 506.15; 95% CI, 356.24 to 656.06; I²=52.02%). Moderate to significant heterogeneity was observed for all parameters (I² > 25%). Subanalysis based on disease severity, mortality, and geographic region of the studies revealed similar inferences.

Conclusion

Thromboinflammatory biomarkers (D-dimer, fibrinogen, CRP, high-sensitivity CRP, ferritin, and interleukin 6) and marker of end-organ damage (high-sensitivity troponin I) are associated with increased severity and mortality in COVID-19 infection.

Does prophylactic inferior vena cava filter reduce the hazard of pulmonary embolism and mortality in severe trauma? A single center retrospective comparative study

•

Severely injured trauma patients are at high risk of venous thromboembolism.

•

Use of IVC filters in trauma patients without recent history of venous thromboembolism is controversial.

•

IVC filter placement did not reduce the hazard of pulmonary embolism or mortality but may pose an increased hazard of deep venous thrombosis.

Objectives

Use of inferior vena cava (IVC) filters in patients following severe trauma without recent history of venous thromboembolism (VTE) is controversial. Our objective was to determine if IVC filter placement in the setting of severe trauma effects the hazard of in-hospital pulmonary embolism (PE), deep venous thrombosis (DVT) and mortality.

Methods

This retrospective study recruited patients from a single Level I Trauma Center between 1/2008 and 12/2013. Inclusion criteria were age>15 years, Injury Severity Score (ISS)>15 and survival>24 h after hospital admission. Patients with VTE diagnosed prior to IVC filter placement were excluded. A Cox proportional hazards regression model was used, adjusting for immortal time bias with landmark analysis at predefined time after injury. Differences between IVC filter and non-IVC filter groups were adjusted using propensity score.

Results

In total 1451 patients were reviewed; 282 patients received an IVC filter and 1169 patients had no IVC filter placed. The mean age was 45.9 vs. 56.9 years and the mean ISS was 29.8 vs. 22.6 in the IVC filter and the non-IVC filter group, respectively. IVC filter placement was not associated with the hazard of PE (HR = 0.46; 95 % CI, 0.12,1.70; P = 0.24) or mortality (HR = 1.02; 95 % CI 0.60,1.75; P = 0.93). However, IVC filter placement was associated with the hazard of DVT (HR = 2.73; 95 % CI, 1.28,5.85; P = 0.01).

Conclusions

In patients with severe trauma, those with prophylactic IVC filter placement did not have a reduced hazard of PE or mortality, but an increased hazard of DVT was observed.

Anticoagulation in COVID-19: A Systematic Review, Meta-analysis, and Rapid Guidance From Mayo Clinic

A higher risk of thrombosis has been described as a prominent feature of coronavirus disease 2019 (COVID-19). This systematic review synthesizes current data on thrombosis risk, prognostic implications, and anticoagulation effects in COVID-19. We included 37 studies from 4070 unique citations. Meta-analysis was performed when feasible. Coagulopathy and thrombotic events were frequent among patients with COVID-19 and further increased in those with more severe forms of the disease. We also present guidance on the prevention and management of thrombosis from a multidisciplinary panel of specialists from Mayo Clinic. The current certainty of evidence is generally very low and continues to evolve.

Calf muscle pump function as a predictor of all-cause mortality

Calf muscle pump (CMP) promotes venous return from the lower extremity and contributes to preload and cardiac output. Impaired CMP function may reflect a measure of frailty or cumulative disease burden or may impede cardiac function. The study objective was to test the hypothesis that impaired CMP negatively impacts survival. Consecutive adult patients who underwent venous strain gauge plethysmography at the Mayo Clinic Gonda Vascular Laboratory (January 1, 1998 - December 31, 2011) were assessed for overall survival. Patients with venous incompetence, venous obstruction or unilateral calf pump dysfunction were excluded. Risk of mortality was assessed with Cox proportional hazard ratios and after adjusting for Charlson Comorbidity Index variables. Over the study period, 2728 patients were included in the analysis. Compared to patients with normal CMP, those with impaired CMP were older (p < 0.001), predominantly female (p = 0.01) and had higher mean Charlson scores (p < 0.001). Patients with impaired CMP had a higher mortality rate at 5 (8.9% vs 2.4%), 10 (17.5% vs 5.9%), and 15 years (22.8% vs 8.3%) compared to those with normal CMP (p < 0.001 for each comparison). Of patients with heart failure, those with impaired CMP had worse survival at each 5-year increment compared to those with normal CMP (p < 0.05 at each increment). In conclusion, impaired CMP appears to be an independent predictor of poor outcomes after adjusting for variables within the Charlson Comorbidity Index. The association between impaired CMP, heart failure, and mortality may represent a negative impact on circulatory function or a surrogate measure of frailty.

Calf Vein Thrombosis Comparison of Outcomes for Axial and Muscular Venous Thrombosis

BACKGROUND

 The objective of this study was to characterize clinical features and outcomes among patients with calf deep vein thrombosis (DVT) limited to the muscular veins compared with axial veins.

METHODS

 Consecutive patients with ultrasound confirmed acute DVT involving the calf veins (January 1, 2016-August 1, 2018) were identified from the Gonda Vascular Center ultrasound database. Patients were divided into axial or muscular groups based on thrombus location. Demographics, management, and outcomes were compared.

RESULTS

 Over the study period, there were 647 patients with calf DVT equally distributed between axial (n = 321) and muscular (n = 326) locations. Within these groups, peroneal and soleal veins were most commonly involved. Nearly all cases were provoked (97%). Synchronous pulmonary embolism (PE) were more common for axial (30.8%) compared to muscular groups (20.2%; p = 0.001); nearly one-third had no pulmonary symptoms. Anticoagulation for a median of 3 months was initiated for 85.5% of both groups. Venous thromboembolism (VTE) recurrence was more common in the axial group (15.9% vs. 7.1%, p = 0.0015) including more frequent DVT propagation (9.4% vs. 3.1%; p = 0.0017) and PE (3.4% vs. 0.6%; p = 0.0168). Major bleeding, clinically relevant nonmajor bleeding, and mortality rates did not differ between groups. Withholding anticoagulation led to more frequent thrombus propagation in the axial group (3.4% vs. 0.9%; p = 0.029).

CONCLUSION

 Several important features distinguish muscular from axial DVT. Axial DVT are more likely to have an associated PE and are more likely to experience recurrent VTE, particularly if anticoagulation is withheld.

Inference from longitudinal laboratory tests characterizes temporal evolution of COVID-19-associated coagulopathy (CAC)

Temporal inference from laboratory testing results and triangulation with clinical outcomes extracted from unstructured electronic health record (EHR) provider notes is integral to advancing precision medicine. Here, we studied 246 SARS-CoV-2 PCR-positive (COVID_pos) patients and propensity-matched 2460 SARS-CoV-2 PCR-negative (COVID_neg) patients subjected to around 700,000 lab tests cumulatively across 194 assays. Compared to COVID_neg patients at the time of diagnostic testing, COVID_pos patients tended to have higher plasma fibrinogen levels and lower platelet counts. However, as the infection evolves, COVID_pos patients distinctively show declining fibrinogen, increasing platelet counts, and lower white blood cell counts. Augmented curation of EHRs suggests that only a minority of COVID_pos patients develop thromboembolism, and rarely, disseminated intravascular coagulopathy (DIC), with patients generally not displaying platelet reductions typical of consumptive coagulopathies. These temporal trends provide fine-grained resolution into COVID-19 associated coagulopathy (CAC) and set the stage for personalizing thromboprophylaxis.

Treatment of upper extremity deep vein thrombosis with apixaban and rivaroxaban

Randomized controlled trials leading to the approval of apixaban and rivaroxaban for venous thromboembolism (VTE) did not include patients with upper extremity deep vein thrombosis (UE-DVT). We sought to evaluate the safety and effectiveness of rivaroxaban and apixaban for the treatment of acute UE-DVT. Consecutive patients with VTE enrolled into the Mayo Clinic VTE Registry, between March 1, 2013 and December 31, 2019, were followed prospectively. Clinical, demographic and imaging data were collected at the time of study recruitment. Patients with a diagnosis of acute UE-DVT who received rivaroxaban, apixaban, LMWH or warfarin were included. Recurrent VTE, major bleeding, clinical-relevant non-major bleeding (CRNMB), and death were assessed at 3-month intervals. During the study period, 210 patients with acute UE-DVT were included; 63 were treated with apixaban, 39 with rivaroxaban, and 108 with LWMH and/or warfarin. Overall 51% had catheter-associated UE-DVT, 60% had a diagnosis of malignancy, and 14% had concurrent pulmonary embolism. Malignancy was more common in patients treated with LMWH/warfarin (67% vs 52%, P = .03). At 3 months of follow up, one (0.9%) recurrent VTE occurred in a patient treated with LMWH/warfarin and one (1.0%) patient treated with apixaban or rivaroxaban (P = .97). Major bleeding occurred in three patients treated with LMWH/warfarin, and in none of those treated with apixaban or rivaroxaban (P = .09). Clinical-relevant non-major bleeding occurred in one patient (0.9%) treated with LWMH/warfarin and two patients (2.0%) treated with apixaban or rivaroxaban (P = .53). Treatment of UE-DVT with apixaban or rivaroxaban appears to be as safe and effective as LMWH/warfarin.

Hemoglobin levels and coronary heart disease risk by age, race, and sex in the reasons for geographic and racial differences in stroke study (REGARDS)

Higher and lower hemoglobin concentrations are associated with coronary heart disease (CHD), but whether this risk is consistent across age, sex, and race is unclear. The Reasons for Geographic And Racial Differences in Stroke (REGARDS) study is an observational cohort study of 30 239 black, and white, adults aged 45 and older recruited 2003-7. Participants were included if they had hemoglobin measures, were CHD-free at baseline, and had all baseline variables. The primary outcome was incident CHD. Multivariable Cox proportional hazards models were used to estimate the hazard ratios (HR) and 95% confidence intervals (CI) for incident CHD by hemoglobin concentration. This was expressed as a continuous variable and divided into age-, sex-, and race-specific quintiles. The 16 332 participants were included, contributing 114 362 person-years of follow-up and 915 incident CHD events. The mean age was 63 years, 35% were male, 41% were black, and the mean baseline hemoglobin was 13.6 g/dL (SD 1.4). A significant non-linear association between hemoglobin and CHD was identified (P < .001). This association differed significantly by race (P = .025) but not by sex or age. In whites, the risk for incident CHD was higher in the lowest (HR 2.28, 95% CI 1.61, 3.33) and highest (HR 1.94, 95% CI 1.35, 2.79) hemoglobin quintiles relative to the third quintile. For blacks, only those in the lowest hemoglobin quintile had an increased risk for incident CHD events (HR 1.70, 95% CI 1.20, 2.41). Hemoglobin is an independent risk factor for CHD in whites and blacks but with different hemoglobin concentrations conferring different risks.

Apixaban and dalteparin in active malignancy-associated venous thromboembolism: The ADAM VTE trial

BACKGROUND

Low-molecular-weight heparin is the guideline-endorsed treatment for cancer-associated venous thromboembolism (VTE). While apixaban is approved for the treatment of acute VTE, limited data support its use in cancer patients.

OBJECTIVES

The primary outcome was major bleeding. Secondary outcomes included VTE recurrence and a composite of major plus clinically relevant non-major bleeding (CRNMB).

PATIENTS/METHODS

Patients with cancer-associated VTE were randomly assigned to receive either apixaban 10 mg twice daily for seven days followed by 5 mg twice daily for six months or subcutaneous dalteparin (200 IU/kg for one month followed by 150 IU/kg once daily).

RESULTS

Of 300 patients randomized, 287 were included in the primary analysis. Metastatic disease was present in 66% of subjects; 74% were receiving concurrent chemotherapy. Major bleeding occurred in 0% of 145 patients receiving apixaban, compared with 1.4% of 142 patients receiving dalteparin [P = .138; hazard ratio (HR) not estimable because of 0 bleeding event in apixaban group]. Recurrent VTE occurred in 0.7% of apixaban, compared to 6.3% of dalteparin patients [HR 0.099, 95% confidence interval [CI], 0.013-0.780, P = .0281). Major bleeding or CRNMB rates were 6% for both groups.

CONCLUSIONS

Oral apixaban was associated with low major bleeding and VTE recurrence rates for the treatment of VTE in cancer patients.

Comparison of apixaban to rivaroxaban and enoxaparin in acute cancer-associated venous thromboembolism

To provide direct comparison between apixaban and rivaroxaban in patients with acute cancer-associated venous thromboembolism (Ca-VTE), consecutive patients treated with apixaban, rivaroxaban, or enoxaparin at Mayo Thrombophilia Clinic (March 1, 2013 to January 31, 2018)) were followed prospectively. The primary effectiveness outcome was venous thromboembolism (VTE) recurrence, and the secondary was mortality. The primary safety outcome was major bleeding, the secondary clinically relevant safety outcome was non-major bleeding (CRNMB), and the third a composite of major and CRNMB. There were 750 patients treated for acute Ca-VTE with apixaban (n = 224), rivaroxaban (n = 163), and enoxaparin (n = 363) within 14 days of diagnosis and for at least 3 months, or until study event. Recurrent VTE was diagnosed in 11 receiving apixaban, 7 receiving rivaroxaban (apixaban vs rivaroxaban hazard ratio (HR) 1.31, 95% confidence interval (95% CI) 0.51-3.36) and 17 in the enoxaparin receiving group (apixaban vs enoxaparin HR 1.14, 95% CI: 0.54, 2.42 and rivaroxaban vs enoxaparin HR 0.85, 95% Cl: 0.36, 2.06). There were 82 deaths in apixaban, 74 rivaroxaban (apixaban vs rivaroxaban HR 1.67, 95% Cl: 1.20, 2.33) and 171 in enoxaparin group (rivaroxaban vs enoxaparin HR 0.73, 95% Cl: 0.56, 0.96). Major bleeding occurred in 11 apixaban, 12 rivaroxaban (apixaban vs rivaroxaban HR 0.73, 95% Cl: 0.32, 1.66) and 21 enoxaparin group (apixaban vs enoxaparin HR 0.89, 95% Cl: 0.43, 1.84 and rivaroxaban vs enoxaparin HR 1.23, 95% Cl: 0.61, 2.50). The CRNMB rate was higher in rivaroxaban compared to apixaban (P = .03) and LMWH (P = .01) groups. Recurrence of VTE and major bleeding were similar in apixaban, rivaroxaban, and enoxaparin groups. Rivaroxaban was associated with higher CRNMB but lower mortality compared to apixaban and enoxaparin.

Apixaban and Rivaroxaban in Patients With Acute Venous Thromboembolism

OBJECTIVE

To compare the clinical efficacy and safety of apixaban with those of rivaroxaban for the treatment of acute venous thromboembolism (VTE).

PATIENTS AND METHODS

Consecutive patients enrolled in the Mayo Thrombophilia Clinic Registry (between March 1, 2013, and January 30, 2018) and treated with apixaban or rivaroxaban for acute VTE were followed forward in time. The primary efficacy outcome was VTE recurrence. The primary safety outcome was major bleeding; the second safety outcome was clinically relevant nonmajor bleeding (CRNMB); and the third was a composite of major bleeding or CRNMB.

RESULTS

Within the group of 1696 patients with VTE enrolled, 600 (38%) were treated either with apixaban (n=302, 50%) or rivaroxaban (n=298, 50%) within the first 14 days of VTE diagnosis and who completed at least 3 months of therapy or had a study event. Recurrent VTE was diagnosed in 7 patients (2.3%) treated with apixaban and in 6 (2%) treated with rivaroxaban (adjusted hazard ratio [aHR], 1.4; 95% CI, 0.5-3.8). Major bleeding occurred in 11 patients (3.6%) receiving apixaban and in 9 patients (3.0%) receiving rivaroxaban (aHR, 1.2; 95% CI, 0.5-3.2). Clinically relevant nonmajor bleeding was diagnosed in 7 patients (2.3%) receiving apixaban and in 20 (6.7%) receiving rivaroxaban (aHR, 0.4; 95% CI, 0.2-0.9). The rates of composite major bleeding or CRNMB were similar (aHR, 0.6; 95% CI, 0.3-1.2). Most study events occurred in patients with cancer.

CONCLUSION

In the setting of a standardized, guideline-directed, patient-oriented clinical practice, the efficacy and safety of apixaban and rivaroxaban for the treatment of acute VTE were comparable.

Testosterone therapy and venous thromboembolism: A systematic review and meta-analysis

BACKGROUND

Testosterone prescribing for men has dramatically increased, and there have been concerns about inappropriate use and adverse events. While regulatory bodies have warned about increased risk of venous thromboembolism (VTE), published clinical data supporting an increased risk for VTE are limited.

OBJECTIVE

To conduct a systematic review of studies examining the association between testosterone therapy in men and VTE.

METHODS

Comprehensive searches of multiple databases were performed from inception through October 3rd, 2018. Randomized control trials (RCTs) and observational studies examining the association between exogenous testosterone (any route) and VTE. Study selection and data extraction were performed by two independent investigators. Random-effect model meta-analyses were used to estimate pooled odds ratios (OR) and 95% confidence intervals (CIs). Heterogeneity among studies was evaluated using the I2 statistic. Risk of bias was assessed using the Cochrane and Newcastle-Ottawa tools.

RESULTS

Six RCTs (n = 2236) and 5 observational studies (n = 1,249,640) were included. Five RCTs were performed in men with documented hypogonadism. The observational studies included: 2 case-control studies, 2 retrospective cohorts, and 1 retrospective cohort with a nested case-control study. There was no evidence of a statistically significant association between VTE and testosterone (OR 1.41, 95%CI 0.96-2.07). Heterogeneity was high (I-squared = 84.4%). The association remained nonsignificant when the analysis was stratified by study design: RCTs (2.05, 95% CI 0.78-5.39); cohort (1.06, 95% CI 0.85-1.33); and case-control (1.34, 95% CI 0.78-2.28). The overall risk of bias was moderate.

CONCLUSIONS

The current evidence is of low certainty but does not support an association between testosterone use and VTE in men.

Thrombosis of atypical location: how to treat patients in the era of direct oral anticoagulants?

In 4% of cases, venous thromboembolism (VTE) involves organ‑related venous territories such as splanchnic, renal, gonadal, and cerebral venous segments, and is often called venous thromboembolism of atypical location (VTE‑AL). Recommendations regarding the method, intensity, and duration of anticoagulant therapy for VTE‑AL are not well established. Direct oral anticoagulants (DOACs) have been a promising alternative to vitamin K antagonists in the treatment of acute VTE. However, all major clinical trials on DOACs excluded patients with VTE‑AL. Therefore, data on the use of DOACs in patients with VTE‑AL are still limited to case reports and small clinical series, with a relative predominance of publications on splanchnic vein thrombosis including mesenteric, splenic, portal, and hepatic vein thrombosis. The only randomized clinical trial comparing a clinical outcome of patients with acute portal vein thrombosis randomized to either rivaroxaban or warfarin treatment yielded significantly impaired results due to the use of an atypical rivaroxaban dose. A prospective registration of clinical outcome for DOACs used in patients with VTE‑AL, in those with VTE of typical location, and in those with VTE‑AL treated with enoxaparin showed similar VTE recurrence and major bleeding rates in all 3 groups. High cancer prevalence, typical for VTE‑AL, significantly impacted survival as well as VTE recurrence rates and major bleeding outcomes in this study. In general, although still limited, the results for DOAC use in VTE‑AL are encouraging and we do not hesitate to use DOACs, particularly rivaroxaban or apixaban, in selected patients with VTE‑AL.