Citations

Introduction: Right ventricle (RV) dysfunction linked with acute Pulmonary embolism (PE) is associated with significant mortality. Several studies have documented use of RV free wall strain (RVS) for assessing mortality, but RV free wall systolic (RVSRs) and early diastolic strain rate (RVSRe) have not been explored. Hypothesis: The study aims to assess the RV function in longitudinal domain of contractility using 2 D speckle tracking echocardiography and evaluate if it was able to predict all-cause mortality at 30 days. Methods: This is a single center prospective study done between November 2012 to June 2020. 293 adult patients with acute PE having echocardiogram performed within 24 hours were enrolled and baseline comorbidities were recorded. 2 D Speckle tracking echocardiography was performed offline. Multiple logistic regression analyses and ROC were performed to evaluate if RV Strain (RVS) and strain rate (systolic-SRs, early diastolic-SRe) were able to predict all-cause mortality at 30 days. Results: Mean age was 65 ± 15 years, 60.7 % males and 41% had coronary artery disease, 29% had cancer and 11% had COPD. Mean free wall (FW) RVS was -19.7±7.7%, FW RV SRs was -0.9±0.4 s -1 , FW RV SRe was 0.8±0.3 s -1 . (Figure A) All-cause mortality was present in 11 patients (3.8%) at 30 days, 17 (5.8%) at 3 months and 29 (9.9%) at 6 months. In the Univariate analysis, FW RVS and FW RVSRs were significantly associated with 30 days all-cause, but after adjusting for age, cancer, and COPD, only FW RVSRs remains significant (p=0.02) with an AUC to predict 30-day all-cause mortality of 0.73 (95% CI 0.54-0.88) a cut-off value of -0.7 had a sensitivity of 73% and specificity of 64% (Figure B) Conclusions: The study demonstrated that RV Free wall SRs measured by 2 D STE is a good prognostic indicator for 30 days all-cause mortality in patients with acute PE. This novel modality could be used for risk stratification in the setting of acute PE.

AbstractAimsThe 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 resultsWe 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 < 0.001) and 3 months (AUC 0.84; 95% CI 0.65–0.99; P = 0.003).ConclusionNon-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.

Abstract Objective Our objective was to evaluate the impact of various blood pressures (BPs) on coronary perfusion and valvular hemodynamics following aortic valve replacement (AVR). Background Lower systolic and diastolic (SBP/DBP) pressures from the recommended optimal target range of SBP < 120–130 mmHg and DBP < 80 mmHg after AVR have been independently associated with increased cardiovascular and all‐cause mortality. Methods The hemodynamic assessment of a 26 mm SAPIEN 3 transcatheter aortic valve (TAV), 29 mm Evolut R TAV, and 25 mm Magna Ease surgical aortic valve (SAV) was performed in a pulsed left heart simulator with varying SBP, DBP, and heart rate (HR) conditions (60 and 120 bpm) at 5 L/min cardiac output (CO). Average coronary flow (CF), effective orifice areas (EOAs), and valvulo‐arterial impedance (Zva) were calculated. Results At HR of 60 bpm, at SBP < 120 mmHg and DBP < 60 mmHg, CF decreased below the physiological lower limit with several different valves. Zva and EOA were found to increase and decrease respectively with increasing SBP and DBP. The same results were found with an HR of 120 bpm. The trends of CF variation with BP were similar in all valves however the drop below the lower physiological CF limit was valve dependent. Conclusion In a controlled in vitro system, with different aortic valve prostheses in place, CF decreased below the physiologic minimum when SBP and DBP were in the range targeted by blood pressure guidelines. Combined with recent observations from patients treated with AVR, these findings underscore the need for additional studies to identify the optimal BP in patients treated with AVR for AS.

AbstractHospitalized 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.

Abstract Background: The precise anatomic location and extent of most venous thromboembolism (VTE) is not captured through diagnostic codes and is a major limitation to research. Correctly identifying the specific site of thrombosis, whether proximal or distal deep vein thrombosis (DVT) or superficial vein thrombosis (SVT) is critical.An accurate natural language processing (NLP) tool would make analysis of large datasets from electronic medical records possible and could be an significant improvement compared to analyses using the International Classification of Diseases codes. Using an open-source NLP tool, we evaluated existing algorithms and then created and validated new NLP algorithms to classify lower extremity thrombosis as not only a DVT or SVT, but also to identify more precise anatomic locations. Methods: A random sample of deidentified ultrasound reports were extracted from electronic medical records, manually reviewed, and classified as either positive or negative for a DVT or SVT (any chronicity). Reports with DVT were further classified into proximal (popliteal, femoral, deep femoral, common femoral, iliac veins, or vena cava) and distal (posterior tibial, anterior tibial, peroneal, soleal, or gastrocnemius veins) DVT. SVT was further classified into greater saphenous vein, small saphenous vein, or other site. Thrombosis near the junction of deep and superficial veins was only designated as involving specific vein segments if there was intraluminal thrombosis at that site. Initial sets of 100 ultrasound reports were used for derivation and reiterative testing of the algorithm, consisting of 50 that were positive for DVT/SVT and 50 that were negative for DVT/SVT. Text from radiology reports underwent cleaning to remove extraneous punctuation, text outside of the "findings" and "impression" section, and all text matches for "superficial femoral vein" were replaced with "femoral vein". Using target phrases, the simple NLP tool either classified the reports as present or absent, signifying either positive or negative for thrombosis at the site of interest. After maximizing accuracy in the derivation cohorts, each NLP algorithm was tested in the complete, manually reviewed dataset. Sensitivity (Sn) and specificity (Sp) were calculated and confidence intervals were determined by the binomial exact method. Results: A total of 1206 ultrasounds were reviewed, among which there was 687 positives for DVT (503 had proximal DVT and 378 had distal DVT involvement). A total of 176 had SVT, 114 with involvement of the great saphenous vein (GSV) and 65 with involvement of the small saphenous vein (SSV). The previously published NLP (designed to identify DVT) had a poor Sn 45.0%, but reasonable Sp (91.0%) for DVT. Among the incorrect positive determinations (n=47), 33 were incorrectly positive due to presence of SVT (in the absence of DVT). Our newly developed NLP algorithm correctly identified DVT at any site (Sn: 96.2% 95% CI 94.5-97.5; 661/687 and Sp: 93.8% 95% CI 91.4-95.7; 487/519). Among ultrasounds positive for DVT, the NLP algorithm to determine proximal DVT site had a 96.0% Sn (95% CI 93.9-97.6; 483/503) and a 97.8% Sp (95% CI 94.5-99.4; 179/183). The algorithm for distal DVT had a 96.8% Sn (95% CI 94.5-98.4; 366/378) and a 96.1% Sp (95% CI 93.3-98.0; 296/308). The algorithm to identify SVT was also highly accurate (Sn 97.7%, 95% CI 94.3-99.4; 172/176 and Sp 95.5%, 95% CI 94.1-96.7; 984/1030). Among ultrasounds positive for SVT, the Sn to determine GSV site was 94.7% (95% CI 88.9-98.0; 108/114) and Sp was 95.1% (95% CI 86.3-99.0; 58/61). The algorithm to identify SSV site had a Sn of 98.5% (95% CI 91.7-99.9; 64/65) and a Sp of 100% (95% CI 96.7-100.0; 110/110). Conclusion: Using a previously published, open source, simple NLP program, we have improved the sensitivity and specificity for identification of DVT and created an algorithm to accurately identify SVT. Using a multifaceted analysis approach, we were able to accurately further subclassify the anatomic location of thrombosis on ultrasound reports. This tool and the developed algorithms will allow analysis of large data sets with minimal effort and great accuracy, capitalizing on the power of large electronic datasets to offer new insights on pathophysiology and clinical prognosis. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

Abstract Background: Reduced or low-dose direct oral anticoagulants (DOACs) have been studied in randomized control trials for the extended prevention of venous thromboembolism (VTE) after 6 months of treatment at the therapeutic doses. The real-world effectiveness as well as utilization of this approach in clinical practice compared to continuing at therapeutic doses is unknown. Aims: Evaluate the efficacy of reduced-dose DOACs compared to standard therapeutic anticoagulation in patients with extended anticoagulation. Methods: Consecutive patients with VTE were identified using the Mayo Clinic VTE Registry from March 1st , 2013 to December 31st, 2020. Patients were followed prospectively for outcomes of VTE recurrence, death, major bleeding and clinically relevant non major bleeding (CRNMB) either in person or by survey. Type of anticoagulation and dose changes were recorded, and progressing to a low dose was treated as an endpoint. In the models relating it to the outcome, it was treated as a time-dependent covariate in the cox models. After completing standard anticoagulation treatment for 3 months with any anticoagulant, patients continuing anticoagulation were divided into two groups: standard therapeutic anticoagulation (any drug) vs those who transitioned to rivaroxaban 10 mg daily or apixaban 2.5mg twice daily any time after 3 months. Patients with recurrent VTE, major or CRNMB during the first 3 months were excluded from further analysis. Results: 219 patients (153 on Apixaban and 66 on Rivaroxaban) were identified in the low dose DOAC and 2521 in the standard anticoagulation group. The mean age was 60.7 years, mean weight was 93.2 Kg and 55.9% were males (Table 1). Patients on low dose DOACs were about the same age and weight compared to standard anticoagulation group. Among all diagnosis categories, patients with active cancer were less likely to be prescribed low dose DOACs (HR 0.56; 95%CI 0.42-0.73; P&lt;0.001), while low dose DOACs prescription was more likely in patients with pulmonary embolism (HR 1.45; 95%CI 1.11-1.89; P=0.007). The median months to start a low dose DOAC after completing the 3 months was 3.1 months with standard deviation of 6.6 months and interquartile range 2.8 months. There was no statistically significant association in the likelihood of going to a low dose group in relation to VTE recurrence (HR 1.36; 95%CI 0.42-4.45; P=0.61) or major bleeding (HR 0.59; 95%CI 0.08-4.37; P=0.61). However, transitioning to low dose DOAC was associated with reduced mortality (HR 0.53; 95%CI 0.35-0.80; P=0.003). Also, patients on low dose DOACs were more likely to have a CRNMB (HR 2.76; 95%CI 1.15-6.62; P=0.02). Conclusion: In this study of patients continuing anticoagulation past 3 months for an initial acute venous thromboembolic event, transitioning to low dose DOACs was not associated with any statistically significant association with VTE recurrence or major bleeding. However, mortality was lower and CRNMB was higher in this unadjusted analysis. Our results show that physicians are not always waiting until 6 months to transition to low doses and low doses are being utilized in cancer patients. Further research is needed to better understand the higher risk for CRNMB identified in this group. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

Abstract Introduction: Patients with coronavirus disease 2019 (COVID-19) have an increased risk for venous thromboembolic events. Thrombotic events contribute to the morbidity and mortality associated with COVID-19 infection, and have prompted investigation into strategies for mitigating thrombosis risk in patients hospitalized with COVID-19 infection. Our team reviewed the charts of patients hospitalized with COVID-19 pneumonia at a tertiary hospital in metropolitan Phoenix Arizona between 2020-2021, to assess frequency and efficacy of utilizing a VTE prophylaxis algorithm designed to prevent thrombosis in patients infected with COVID-19. Methods: A total of 846 patients were retrospectively evaluated to determine if they were treated with guideline-appropriate anticoagulation while hospitalized with COVID-19, as well as if they developed venous or arterial thrombotic events, or major or minor bleeds. 317 patients were excluded for taking therapeutic anticoagulation prior to admission, or for having a COVID-19 diagnosis &gt;7 days after admission. Appropriate anticoagulation was determined by an institutionally designed COVID-19 thromboprophylaxis algorithm, based on platelet count, d-dimer, bleeding risk, and level of medical care required. Regimen options included: no anticoagulation, prophylactic enoxaparin (40 mg SQ daily) or heparin in the setting of kidney dysfunction, weight-based dosing of enoxaparin (40 mg SQ BID if BMI&gt;40), intermediate intensity enoxaparin without thrombus (30 mg BID if BMI&lt;40, or 40 mg BID if BMI&gt;40), and therapeutic anticoagulation (for example enoxaparin 1 mg/kg BID) with thrombus. Demographics: Demographic data and clinical characteristics were collected for 529 patients. Average age was 59 years old, and the majority were men (58.4%). Most patients were White (58.3%), followed by Hispanic (17.8%), or Native American (15.7%). Fewer patients had a normal BMI (21.3%; BMI 18.5 - 24.9) compared to those who were overweight (31.2%; BMI 25-29.9) or obese (43.1% BMI &gt; 30). Other comorbidities included Type 1 or Type 2 diabetes mellitus (N= 172, 32.5%), hypertension (N = 271, 51.2%), and hyperlipidemia (N = 176, 33.3%). Results: A total of 42 patients (8%), were diagnosed with a venous thrombosis during hospitalization. Patients admitted to the ICU were significantly more likely to have a thrombotic event of any type compared to non-ICU patients (21.6% to 5.7%; p &lt; 0.001). Specifically, critically ill patients had higher incidences of deep vein thrombosis (9.5% to 0.7%), pulmonary emboli (8.1% to 4.8%), and superficial thrombi (2.7% to 0.2%). Only 1.1% of patients (6/529) experienced any bleeding, of which 3 were classified as a major bleed. Discussion: Among patients hospitalized at our institution with COVID-19, the majority were anticoagulated appropriately according to the COVID-19 thromboprophylaxis algorithm. Overall incidence of thrombosis in the study population was 8%. A significantly higher percent of critically ill patients had thrombi, supporting reports of correlation between severity of illness and thrombosis risk. The two regimens of anticoagulation least adhered to were weight-based and intermediate-based dosing, likely reflecting a departure from the hospital's thromboprophylaxis regimens prior to COVID-19 pandemic. Further studies are needed to characterize whether identifiable risk factors correlate with the incidence of thrombosis, and whether treatment with lower than recommended doses of anticoagulation, based on the COVID-19 thromboprophylaxis algorithm, were associated with thrombosis. Disclosures No relevant conflicts of interest to declare.