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.

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.

Reduced calf muscle pump function is a risk factor for venous thromboembolism: a population-based cohort study.

The calf muscle pump is a major determinate of venous return in the legs but has not been studied as a risk factor for venous thromboembolism (VTE). A population-based cohort study of Olmsted County, Minnesota residents was performed using calf pump function (CPF) measurements from venous plethysmography studies from 1998 to 2015. Patients with a history of VTE were excluded. Nursing validated VTE outcomes from the Rochester Epidemiology Project were identified after the index study date, and patients with reduced CPF (rCPF) were compared with patients with normal CPF. A total of 1532 patients with recorded CPF (28% air and 72% strain gauge plethysmography) were included; 591 (38.5%) had normal CPF, 353 (23.0%) had unilateral rCPF, and 588 (38.3%) had bilateral rCPF. Any VTE occurred in 87 patients (5.7%) after a median follow-up of 11.7 years (range, 0-22.0 years). Comparing patients with bilateral reduced to bilateral normal CPF, the unadjusted hazard ratio (HR) for incident VTE was 2.0 (95% confidence interval [CI], 1.2-3.4) and after adjusting for age, BMI, and Charlson Comorbidity Index, the HR was 1.68 (95% CI, 0.98-2.89). The adjusted HR for ipsilateral deep vein thrombosis was evaluated in 3064 legs comparing legs with reduced to normal CPF and was 1.71 (95% CI, 1.03-2.84). Mortality was significantly higher in both the bilateral (P < .001) and unilateral (P < .001) rCPF groups compared with normal CPF. Our results demonstrate that CPF is a risk factor for VTE in an otherwise low-risk ambulatory population and might be a useful component in risk stratification models.

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.

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.

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 (4/8/2015 - 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.

Popliteal cysts are not a risk factor for lower extremity deep vein thrombosis.

BACKGROUND: Popliteal cysts (PC) result from distension of the gastrocnemio-semimembranosous bursa. Published reports indicate coincident PC and deep vein thrombosis (DVT). Whether the presence of PC increase the risk of deep vein thrombosis (DVT) remains unclear. METHODS: Lower extremity venous Duplex ultrasound (DUS) reports were evaluated across the Mayo Clinic Enterprise (Rochester, Minnesota, Jacksonville, Florida, Scottsdale, Arizona, and the Mayo Clinic Health System) in patients ≥ 18 years of age. Natural language processing (NLP) algorithms were created and validated to identify acute lower extremity DVT and PC from these reports. To determine whether there is a link between PC and lower extremity DVT, the frequency of PC among cases (ultrasounds with acute DVT) were compared to controls (ultrasounds without acute DVT). RESULTS: A total of 357,703 lower extremities venous DUS were performed in 237,052 patients (mean age 63.3 ± 16.6, 54.4% were female) between 1992 and 2021. Acute DVT was identified in 32,572 (9.1%) DUS, and PC in 32,448 (9.1%). PC were seen in a lower frequency (8.0%) of ultrasounds with acute DVT than those without (9.2%) acute DVT (OR: 0.85, 95% CI: 0.82 to 0.89, p < 0.001). In a multivariate logistic regression model after adjusting for age, sex, and race, PCs were not positively associated with acute DVT (adjusted OR: 0.84, 95% CI: 0.81 to 0.88). CONCLUSIONS: PC are an incidental finding or an alternative diagnosis on lower extremity venous DUS, a finding that increases significantly with age. PC were not a risk factor in the development of lower extremity DVT.

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.

Effectiveness and safety of apixaban and rivaroxaban for acute venous thromboembolism therapy in patients with extremes in bodyweight.

OBJECTIVES: To investigate the association of extremes in bodyweight (EBW) and outcomes in patients with acute venous thromboembolism (VTE). Recurrent VTE, major bleeding, and clinically relevant non-major bleeding were compared between patients with bodyweight <60 kg, 60-120 kg, and >120 kg. METHODS: Consecutive patients enrolled in the Mayo Clinic VTE Registry (03/28/2013-8/31/2019) with acute VTE were followed prospectively. Patient status was assessed in person, by mailing a written questionnaire, or by a scripted phone interview. RESULTS: Among 2577 patients with weight ranging from 27.0 kg to 263.2 kg, 2123 (82%) had a bodyweight between 60 and 120 kg, 223 (8.7%) had bodyweight < 60 kg, and 230 (8.9%) had bodyweight >120 kg. Patients with bodyweight <60 kg treated with DOACs had higher 3- and 6-month incidence of major bleeding compared to the bodyweight 60-120kg group (4.4% vs 1.1%, P = .03, and 4.4% vs 1.4%, P = .05, respectively). Patients with bodyweight >120 kg and cancer on rivaroxaban had higher VTE recurrence compared to bodyweight 60-120kg group (P = .01). CONCLUSIONS: Treatment of acute VTE is associated with a higher incidence of bleeding in patients with bodyweight <60 kg. A higher VTE recurrence rate occurred only in cancer patients with bodyweight >120 kg on rivaroxaban.

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.

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.

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.

Resolution of acute lower extremity deep vein thrombosis with rivaroxaban compared to warfarin.

Thrombosis resolution is an important component of treatment for deep vein thrombosis (DVT) and multiple anticoagulants are now available. It is unknown whether rivaroxaban contributes to a higher degree of thrombus resolution compared to conventional anticoagulation with warfarin. Our objective was to compare thrombus resolution for rivaroxaban versus warfarin treated patients with acute lower extremity DVT. Consecutive patients treated for proximal or distal lower extremity DVT with rivaroxaban were identified from the Mayo Thrombophilia Clinic Anticoagulants Registry (November 2015-June 2016) and compared to patients treated with warfarin. Ultrasonography/Doppler images were analyzed by two independent radiologists blinded to anticoagulant and using a standardized assessment algorithm. A total of 111 patients with DVT were studied. Sixty-three rivaroxaban treated patients were compared to 48 warfarin treated patients over a median follow up of 92 and 97 days, respectively. Percentage of patients with total or partial resolution of thrombosis was similar in rivaroxaban and warfarin treated groups (95.2% vs. 91.7%, p = 0.46, respectively); also the proportion of patients with total thrombus resolution was not significantly different (38.1% vs. 29.2%, p = 0.42, respectively). There was no significant difference in the proportion of patients with no thrombus resolution between rivaroxaban and warfarin treated groups either (4.8% vs. 2.1%, p = 0.63). Thrombus propagation with warfarin therapy was observed in 6.3% of patients treated with warfarin and in none of the patients from the rivaroxaban group (p = 0.08). Resolution of acute lower extremity DVT in patients treated with rivaroxaban is similar to those treated with warfarin.

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.

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.

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.