Patients with antiphospholipid syndrome and a first venous or arterial thrombotic event: clinical characteristics, antibody profiles and estimate of the risk of recurrence.

OBJECTIVES: Thrombosis in antiphospholipid syndrome (APS) involves in most cases the venous circulation. Why in some patients thrombotic APS affects the arterial circulation and in particular cerebral circulation is unknown. In previous studies, both patient characteristics and antiphospholipid antibody types and titers have been associated with arterial thrombosis. Aim of this study was to compare the clinical characteristics and laboratory findings of venous and arterial thrombotic APS from a large series of patients. METHODS: Data were retrieved from the Start 2 antiphospholipid, a multicenter prospective register of long-term collected data from Thrombosis Centers in Italy. RESULTS: Of 167 patients with thrombotic APS, 114 (68 %) had a venous and 53 (32 %) had an arterial event as first clinical manifestation. Several clinical characteristics and risk factors were different among groups in univariate analysis. Using logistic regression analysis, reduced creatinine clearance and hyperlipidemia were independent variable for the occurrence of arterial APS. Notably, no difference in antiphospholipid antibody profiles and aß2-Glycoprotein I levels were found between groups. A higher adjusted global antiphospholipid syndrome score (aGAPSS) was found in arterial group indicating a possible high recurrence rate in arterial APS. CONCLUSIONS: These data have pathophysiological and clinical implication since associated conditions might predispose patients to arterial rather than venous events and call to a close monitoring and treatment of arterial APS due to their increased tendency to recurrence.

Statins under-treatment and mortality in patients with atrial fibrillation. Insights from the nationwide START registry.

BACKGROUND AND AIMS: Statins are mainstream drugs for cardiovascular (CV) prevention, but under-prescription is an important clinical challenge. Data on the use of single statins and on the rate of under-prescription in atrial fibrillation (AF) are lacking. We evaluated the association of statin underuse with mortality risk in a large AF cohort. METHODS AND RESULTS: As many as 5477 patients from the Italian nationwide START registry were included. The prevalence of different statins was reported and the association of under prescription with all-cause and CV mortality investigated. Mean age was 80.2 years, and 46.4% were women. Among 2899 patients with a clinical indication to statin, only 1578 (54.4%) were on treatment. In a mean follow-up of 22.5 ± 17.1 months, 491 (4.7%/year) deaths occurred (106 CV deaths, 1.0%/year). Atorvastatin and Simvastatin were inversely associated with all-cause (HR 0.692, 95% CI 0.519-0.923, p = 0.012 and HR 0.598, 95% CI 0.428-0.836, p = 0.003, respectively) and CV death (HR 0.372, 95% CI 0.178-0.776, p = 0.008 and HR 0.306, 95% CI 0.123-0.758, p = 0.010, respectively). The 1321 untreated patients were older, more frequently women and with a higher prevalence of diabetes, previous cerebrovascular disease, peripheral artery disease compared to those on treatment. Statin undertreatment was associated with higher risk of all-cause (HR 1.400, 95% CI 1.078-1.819, p = 0.012) and CV death (HR 2.057, 95% CI 1.188-3.561, p = 0.010). CONCLUSIONS: AF patients with an indication to statins but left untreated show a high risk of all-cause and CV mortality. Implementation of statin prescription in the AF population can help reducing the residual mortality risk.

Bleeding and mortality risk in patients implanted with mechanical prosthetic heart valves with and without thrombocytopenia. Insights from the nationwide PLECTRUM registry.

Previous studies showed that mechanical prosthetic heart valve (MPHV) patients may develop thrombocytopenia, but its association with clinical outcomes has not been investigated. We enrolled 1,663 patients with available platelet count from the multicenter nationwide retrospective PLECTRUM registry to investigate the association of thrombocytopenia with all-cause mortality and major bleeding (MB) in patients implanted with MPHV. Thrombocytopenia was defined by platelet count <150 × 109/L. Overall, 44.9% of patients were women and the mean age was 56.7 years. At baseline, 184 (11.1%) patients had thrombocytopenia. Patients with thrombocytopenia were more frequently men and elderly. Platelet count showed an age-dependent decline in men but not in women. We found an increased risk of death in patients with age ≥ 65 years, with a low anticoagulation quality, concomitant arterial hypertension, heart failure, a higher INR range, or with thrombocytopenia (OR 1.739, 95%CI 1.048-2.886, p = .032). At multivariable logistic regression, patients with age ≥65 years, concomitant AF and thrombocytopenia (OR 1.907, 95%CI 1.219-2.983, p = .005) had an increased risk of MBs. In MPHV patients, thrombocytopenia is associated with an increased risk of death and MB. There is a growing need for a sex- and age-specific threshold to define platelet count in adult patients.

Sex-based difference in anticoagulated patients with mechanical prosthetic heart valves and long-term mortality risk.

BACKGROUND: Vitamin K antagonists (VKAs) reduce thromboembolism in patients with mechanical prosthetic heart valves (MPHV). It is unclear whether a sex-based difference in MPHV patients regarding valve site, anticoagulation quality, and mortality risk does exist. METHODS: We analysed 2111 MPHV patients from the nationwide PLECTRUM study promoted by the Italian Federation of Anticoagulation Clinics (FCSA). We analysed the site of MPHV, anticoagulation quality, as assessed by the time in therapeutic range (TiTR), and mortality risk in women and men. RESULTS: The mean age of the patients was 56.8 ± 12.3 years. Women were older with a lower prevalence of ischemic heart disease and smoking habit and a higher prevalence of atrial fibrillation at baseline. Aortic MPHV was more frequent in men (74.7% vs 43.3%, P < .001), whereas mitral (41.1% vs 17.6%, P < .001) and mitro-aortic (15.6% vs 7.7%, P < .001) MPVH in women. The association between female sex and mitral/mitro-aortic site remained at multivariable logistic regression analysis (Odds Ratio 3.623, 95% Confidence Interval [CI] 2.947-4.455, P < .001). Regarding anticoagulation quality, women showed lower mean TiTR (63.0 ± 19.4 vs 57.5 ± 19.2, P < .001), and a higher proportion of TiTR < 60% (54.9% vs 43.3%, P < .001). During a mean follow-up of 123 months (21 665 pt-years), 152 deaths occurred (0.7%/year); 83 in the aortic (0.63%/year) and 69 in the mitral/mitro-aortic (0.81%/year) group. At multivariable Cox proportional hazard regression analysis, female sex was not associated with mortality (HR 0.953, 95%CI 0.678 1.340, P = .783). CONCLUSIONS: Female sex is independently associated with mitral/mitro-aortic MPHV. Despite a lower TiTR in women, mortality risk did not differ between the two groups.

Comparison of Anticoagulation Quality between Acenocoumarol and Warfarin in Patients with Mechanical Prosthetic Heart Valves: Insights from the Nationwide PLECTRUM Study.

Vitamin K antagonists are indicated for the thromboprophylaxis in patients with mechanical prosthetic heart valves (MPHV). However, it is unclear whether some differences between acenocoumarol and warfarin in terms of anticoagulation quality do exist. We included 2111 MPHV patients included in the nationwide PLECTRUM registry. We evaluated anticoagulation quality by the time in therapeutic range (TiTR). Factors associated with acenocoumarol use and with low TiTR were investigated by multivariable logistic regression analysis. Mean age was 56.8 ± 12.3 years; 44.6% of patients were women and 395 patients were on acenocoumarol. A multivariable logistic regression analysis showed that patients on acenocoumarol had more comorbidities (i.e., ≥3, odds ratio (OR) 1.443, 95% confidence interval (CI) 1.081-1.927, p = 0.013). The mean TiTR was lower in the acenocoumarol than in the warfarin group (56.1 ± 19.2% vs. 61.6 ± 19.4%, p < 0.001). A higher prevalence of TiTR (<60%, <65%, or <70%) was found in acenocoumarol users than in warfarin ones (p < 0.001 for all comparisons). Acenocoumarol use was associated with low TiTR regardless of the cutoff used at multivariable analysis. A lower TiTR on acenocoumarol was found in all subgroups of patients analyzed according to sex, hypertension, diabetes, age, valve site, atrial fibrillation, and INR range. In conclusion, anticoagulation quality was consistently lower in MPHV patients on acenocoumarol compared to those on warfarin.

Determinants of low-quality warfarin anticoagulation in patients with mechanical prosthetic heart valves. The nationwide PLECTRUM study.

Quality of warfarin therapy in patients with a mechanical prosthetic heart valve (MPHV) has been barely investigated. We analysed determinants of low time in the therapeutic range (TiTR <60%) in 2111 patients with MPHVs from the nationwide PLECTRUM study by the Italian Federation of Anticoagulation Clinics. Overall, 48·5% of patients had a TiTR of < 60%. At logistic regression analysis, arterial hypertension (odds ratio [OR] 1·502, P < 0·001), diabetes (OR 1·732, P < 0·001), heart failure (OR 1·484, P = 0·004), mitral site (vs. aortic) (OR 1·399, P = 0·006), international normalised ratio (INR) ranges of 2·5-3·5 (OR 2·575, P < 0·001) and 3·0-4·0 (OR 8·215, P < 0·001) associated with TiTR < 60%. TiTR is substantially suboptimal in MPHV patients, particularly in higher INR ranges.

Duration of anticoagulation after isolated pulmonary embolism.

In the D-dimer and ULtrasonography in Combination Italian Study (DULCIS), serial D-dimer measurement in combination with assessment of residual thrombosis (in patients with deep vein thrombosis (DVT)) identified patients who safely discontinued anticoagulation after an unprovoked venous thromboembolism (VTE).In this subgroup analysis, the value of D-dimer tests was assessed in patients with isolated pulmonary embolism (PE) compared with those with DVT, with or without PE (DVT/PE). The DULCIS database was reanalysed in relation to this target.26.8% of the DULCIS patients had isolated PE as the index event; this was more prevalent in females (34.1%) than in males (21.1%; p<0.0001). The rate of positive D-dimer was similar in isolated PE and DVT/PE. The rate of recurrences was not different in isolated PE or DVT/PE patients (4.8% ppy versus 3.8% ppy; nonsignificant) who stopped anticoagulation for negative D-dimer, but it was markedly high (11.2% ppy; p<0.0001) in those with isolated PE who remained without anticoagulation despite positive D-dimer. Recurrences were more frequently new isolated PE in patients with isolated PE than with DVT/PE (six (46.2%) out of 13 versus two (7.4%) out of 27; p=0.0085).Serial D-dimer assessment can inform on the risk of recurrent VTE and help determine the duration of anticoagulation in patients with isolated PE.

D-dimer to guide the duration of anticoagulation in patients with venous thromboembolism: a management study.

The optimal duration of anticoagulation in patients with venous thromboembolism (VTE) is uncertain. We investigated whether persistently negative D-dimers in patients with vein recanalization or stable thrombotic burden can identify subjects at low recurrence risk. Outpatients with a first VTE (unprovoked or associated with weak risk factors) were eligible after at least 3 months (12 in those with residual thrombosis) of anticoagulation. They received serial D-dimer measurements using commercial assays with predefined age/sex-specific cutoffs and were followed for up to 2 years. Of 1010 patients, anticoagulation was stopped in 528 (52.3%) with persistently negative D-dimer who subsequently experienced 25 recurrences (3.0% pt-y; 95% confidence interval [CI], 2.0-4.4%). Of the remaining 482 patients, 373 resumed anticoagulation and 109 refused it. Recurrent VTE developed in 15 patients (8.8% pt-y; 95% CI, 5.0-14.1) of the latter group and in 4 of the former (0.7% pt-y; 95% CI, 0.2-1.7; hazard ratio = 2.92; 95% CI, 1.87-9.72; P = .0006). Major bleeding occurred in 14 patients (2.3% pt-y; 95% CI, 1.3-3.9) who resumed anticoagulation. Serial D-dimer measurement is suitable in clinical practice for the identification of VTE patients in whom anticoagulation can be safely discontinued. This study was registered at clinicaltrials.gov as #NCT00954395.

Hyperhomocysteinemia in patients with pulmonary embolism is associated with impaired plasma fibrinolytic capacity.

Hyperhomocysteinemia (HHcy) affects haemostasis and shifts its balance in favour of thrombosis. In vitro and in vivo studies suggested that HHcy may impair fibrinolysis either by influencing the plasma levels of fibrinolytic factors or by altering the fibrinogen structure. We investigated the influence of mild HHcy levels on plasma fibrinolytic potential by using clot lysis time (CLT) and fibrin susceptibility to plasmin-induced lysis in 94 patients with previous pulmonary embolism and no pulmonary hypertension. CLT was measured as lysis time of tissue factor induced clots exposed to exogenous tissue plasminogen activator (t-PA). The rate of in vitro plasmin-mediated cleavage of fibrin ß-chain was assessed over a 6-h period on fibrin clots, which were obtained by exposition to thrombin of purified fibrinogen. Homocysteine plasma levels were measured by Abbott Imx immunoassay and we considered as altered the values above 15 µmol/L according to the literature. In 68 patients homocysteine levels were below 15 µmol/L (NHcy) and in 26 they were above (HHcy). Significant differences were observed between the two groups regarding plasma fibrinolytic potential (p = 0.016), TAFIact (expressed as clot lysis ratio) (p = 0.02), t-PA (0.008) and PLG (0.037), but not for the other assessed components. The HHcy-patients had a threefold higher risk to have an impaired fibrinolysis. Instead, a multivariate logistic regression analysis adjusted for significances of univariate showed that HHcy (OR 5.2 95% CI 1.7-15.9; p = 0.003) and BMI (OR 5.0 95% CI 1.6-15.9; p = 0.006) resulted independently associated with impaired fibrinolytic activity. HHcy affects TAFI-mediated hypofibrinolysis but not fibrin(ogen) structure or function as documented by fibrin degradation analysis.

Renin-angiotensin-aldosterone system inhibitors and mortality risk in elderly patients with atrial fibrillation. Insights from the nationwide START registry.

BACKGROUND: Arterial hypertension is the most common cardiovascular comorbidity in atrial fibrillation (AF). Few studies investigated management strategies of hypertension in AF. MATERIALS AND METHODS: We included 5769 AF patients on oral anticoagulants from the nationwide ongoing Italian START registry. We investigated the prescription of antihypertensive drugs and mortality risk. Subgroup analyses according to sex and major cardiovascular comorbidities were performed. RESULTS: Mean age was 80.8 years, 46.1% were women; 80.3% of patients were hypertensive. Furosemide (30.1%) was the most frequent diuretic followed by hydrochlorothiazide (15.4%) and potassium canrenoate (7.9%). 61.1% received ß-blockers: 34.2% bisoprolol, 6.2% atenolol. Additionally, 36.9% were on angiotensin converting enzyme inhibitors (ACE-I): ramipril (20.9%), enalapril (5.3%) and perindopril (2.8%); 31.7% were on angiotensin receptors blockers (ARBs): valsartan (7.6%) and irbesartan (6.4%). Amlodipine and lercanidipine were prescribed in 14.0% and 2.3%, respectively. ACE-I (p < 0.001), α-blockers (p = 0.020) and Dihydropyridines calcium channel blockers (p = 0.004) were more common in men, while ARBs (p = 0.008), thiazide diuretics (p < 0.001) and ß-blockers (p < 0.001) in women. During 22.61 ± 17.1 months, 512 patients died. Multivariable Cox regression analysis showed that ACE-I (Hazard ratio [HR] 0.758, 95% Confidence Interval [95%CI] 0.612-0.940, p = 0.012) and ARBs (HR 0.623, 95%CI 0.487-0.796, p < 0.001) inversely associated with mortality. ACE-I/ARBs inversely associated with mortality in both sexes and in patients with diabetes. This associastion was evident for ACE-I in patients with previous cardiovascular disease, and for ARBs in HF. CONCLUSION: A lower mortality risk was found in AF patients on ACE-I/ARBs. Different prescription patterns of antihypertensive drugs between men and women do exist.

Low platelet count at admission has an adverse impact on outcome in patients with acute coronary syndromes: from the START Antiplatelet registry.

Some previous observations suggest that a low platelet count is associated with an increased risk of adverse outcomes in patients with acute coronary syndromes (ACS). However, most of the data come from post-hoc analyses of randomized controlled trials and from studies including thrombocytopenia developed during hospital stay. Our aim was to assess the impact of low platelet count at admission on cardiovascular outcomes and treatment approach in patients hospitalized for ACS in a current real-life setting in Italy. Patients admitted to Italian coronary care units for ACS were enrolled in the START-ANTIPLATELET registry. Baseline clinical characteristics and treatment at discharge were recorded. Patients were followed-up at 6 months, 1 year and yearly thereafter. Low platelet count was defined as a count at admission < 150 > 100 k/µl or < 100 k/µL. Among 1894 enrolled patients, 157 (8.3%) had a platelet count < 150 > 100 k/µl and 30 (1.6%) < 100 k/µl. The median follow-up was 12.3 months (0.4-50.1). patients with low platelets were older (72 ± 10.4 vs 66 ± 12.4 years, p = 0.006), more frequently males (82.9 vs 72.1%, p = 0.001), hypertensive (90.0% vs 70.4%, p = 0.03), with non-valvular atrial fibrillation (NVAF) (17.1 vs 8.6%, p = 0.02), and peripheral arterial disease (11.5 vs 6.2% p = 0.01) and/or had a previous myocardial infarction (40 vs 18.7%, p = 0.008) and/or a PCI (14.6 vs 7.8%, p = 0.001) than patients with normal platelets. A slightly, but significantly, lower percentage of thrombocytopenic patients were treated with primary PCI (78.1 vs 84.4%, p = 0.04) and they were more frequently discharged on aspirin plus clopidogrel rather than aspirin plus newer P2Y12 antagonists (51.9 vs 65.4%, p = 0.01). MACE-free survival was significantly shorter in thrombocytopenic patients compared to patients with normal platelets (< 150 > 100 k/µl: 37.6 vs 41.8 months, p = 0.002; HR = 2.7, 95% CIs 1.4-5.2; < 100 k/µl: 31.7 vs 41.8 months, p = 0.01; HR = 6.5, 95% CIs 1.5-29.1). At multivariate analysis, low platelet count, age at enrollment, low glomerular filtration rate, low ejection fraction, a previous ischemic stroke and NVAF were independent predictors of MACE. A low platelet count at admission identifies a subgroup of ACS patients with a significantly increased risk of MACE and these patients should be managed with special care to prevent excess adverse outcomes.

Machine learning approach for prediction of outcomes in anticoagulated patients with atrial fibrillation.

BACKGROUND: The accuracy of available prediction tools for clinical outcomes in patients with atrial fibrillation (AF) remains modest. Machine Learning (ML) has been used to predict outcomes in the AF population, but not in a population entirely on anticoagulant therapy. METHODS AND AIMS: Different supervised ML models were applied to predict all-cause death, cardiovascular (CV) death, major bleeding and stroke in anticoagulated patients with AF, processing data from the multicenter START-2 Register. RESULTS: 11078 AF patients (male n = 6029, 54.3%) were enrolled with a median follow-up period of 1.5 years [IQR 1.0-2.6]. Patients on Vitamin K Antagonists (VKA) were 5135 (46.4%) and 5943 (53.6%) were on Direct Oral Anticoagulants (DOAC). Using Multi-Gate Mixture of Experts, a cross-validated AUC of 0.779 ± 0.016 and 0.745 ± 0.022 were obtained, respectively, for the prediction of all-cause death and CV-death in the overall population. The best ML model outperformed CHA2DSVA2SC and HAS-BLED for all-cause death prediction (p < 0.001 for both). When compared to HAS-BLED, Gradient Boosting improved major bleeding prediction in DOACs patients (0.711 vs. 0.586, p < 0.001). A very low number of events during follow-up (52) resulted in a suboptimal ischemic stroke prediction (best AUC of 0.606 ± 0.117 in overall population). Body mass index, age, renal function, platelet count and hemoglobin levels resulted the most important variables for ML prediction. CONCLUSIONS: In AF patients, ML models showed good discriminative ability to predict all-cause death, regardless of the type of anticoagulation strategy, and major bleeding on DOAC therapy, outperforming CHA2DS2VASC and the HAS-BLED scores for risk prediction in these populations.

Inappropriate Underdosing of Direct Oral Anticoagulants in Atrial Fibrillation Patients: Results from the START2-AF Registry.

Background: Direct oral anticoagulants (DOACs) are recommended for stroke prevention in non-valvular atrial fibrillation (NVAF) patients. We aimed to describe the prevalence of inappropriate DOACs dose prescription in the START2-AF Registry, the outcomes according to the appropriateness of the dosage, and the factors associated with inappropriate dose prescription. Methods: Patients' demographics and clinical data were prospectively collected as electronic files in an anonymous form on the website of the START2-Registry; DOACs dosage was determined to be appropriate when prescribed according to the European Heart Rhythm Association Guidelines. Results: We included 5943 NVAF patients on DOACs; 2572 (46.3%) were female patients. The standard dose (SD) was prescribed to 56.9% of patients and the low dose (LD) was prescribed to 43.1% of patients; 38.9% of all NVAF patients received an inappropriate LD DOAC and 0.3% received inappropriate SD. Patients treated with LD DOAC had a significantly higher rate of all bleedings (RR 1.5; 95% CI 1.2-2.0), major bleedings (RR 1.8; 95% CI 1.3-1.7), and mortality (RR 2.8; 95% CI 1.9-4.1) with respect to patients treated with SD DOAC. No difference was found among patients treated with appropriate and inappropriate LD regarding bleeding, thrombotic, and mortality rates. Age, body weight <60 kg, and renal failure were significantly associated with inappropriate LD DOAC prescription. Conclusions: Inappropriate LD DOACs in NVAF patients is not associated with a reduction in bleeding risk, nor with an increased thrombotic risk. Instead, it is associated with higher mortality rate, suggesting that, in clinical practice, underdosing is preferred for patients at particularly high risk for adverse events.

Long-Term Outcomes in Two-Year Follow-Up after Primary Treatment in Patients with a Prior Venous Thromboembolic Event: A Prospective, Observational, Real-Life Study.

BACKGROUND: Patients with acute venous thromboembolism (VTE) need anticoagulation (AC) therapy for at least 3/6 months (primary treatment); after that period, they should receive a decision on the duration of therapy. METHODS: This study examined the complications occurring during two years of follow-up (FU) in patients with a first VTE who were recruited in 20 clinical centers and had discontinued or prolonged AC. They were included in the START2-POST-VTE prospective observational study. RESULTS: A total of 720 patients (53.5% males) who, after the completion of primary treatment, had received the decision to continue (n = 281, 39%; 76.1% with a DOAC) or discontinue (n = 439, 61%) AC were followed up for 2 years (total FU = 1318 years). The decision to prolong or suspend AC was made in similar proportions in patients with unprovoked or provoked index events. Courses of sulodexide treatment or Aspirin (100 mg daily) were prescribed to 20.3% and 4.5%, respectively, of the patients who discontinued AC. The bleeding rate was significantly higher in patients who extended AC (1.6% pt/y) than in those who stopped AC (0.1% pt/y; p = 0.001) and was higher in patients using standard-dose DOACs (3.1% pt/y) than in those using reduced-dose DOACs (0.4% pt/y). The recurrent VTE rates were similar between the two groups (2.2% pt/y during AC vs. 3% pt/y off AC). CONCLUSION: Physicians' decisions about AC duration were independent of the unprovoked/provoked nature of the index event. The bleeding rate was higher in patients who continued AC using standard-dose DOACs. Surprisingly, the rate of thrombotic recurrence was not different between those who continued or discontinued AC. Randomized studies comparing different procedures to decide on the duration of AC after a first VTE are needed.

Thrombotic events associated with low baseline direct oral anticoagulant levels in atrial fibrillation: the MAS study.

ABSTRACT: Although effective and safe, treatment with direct oral anticoagulants (DOAC) in atrial fibrillation (AF) is still associated with thrombotic complications. Whether the measurement of DOAC levels may improve treatment efficacy is an open issue. We carried out the observational, prospective, multicenter Measure and See (MAS) study. Blood was collected 15 to 30 days after starting DOAC treatment in patients with AF who were followed-up for 1 year. Plasma samples were centralized for DOAC level measurement. Patients' DOAC levels were converted into drug/dosage standardized values to allow a pooled analysis in a time-dependent, competitive-risk model. The measured values were transformed into standardized values (representing the distance of each value from the overall mean) by subtracting the DOAC-specific mean value from the original values and dividing by the standard deviation. Trough and peak DOAC levels were assessed in 1657 and 1303 patients, respectively. In total, 21 thrombotic complications were recorded during 1606 years of follow-up (incidence of 1.31% of patients per year). Of 21 thrombotic events, 17 occurred in patients whose standardized activity levels were below the mean of each DOAC (0); the incidence was the highest (4.82% of patients per year) in patients whose standardized values were in the lowest class (-1.00 or less). Early measurement of DOAC levels in patients with AF allowed us to identify most of the patients who, having low baseline DOAC levels, subsequently developed thrombotic complications. Further studies are warranted to assess whether thrombotic complications may be reduced by measuring baseline DOAC levels and modifying treatment when indicated. This trial was registered at www.ClinicalTrials.gov as #NCT03803579.

MORE EARLY BLEEDS ASSOCIATED WITH HIGH BASELINE DIRECT ORAL ANTICOAGULANT LEVELS IN ATRIAL FIBRILLATION: THE MAS STUDY.

Treatment with direct oral anticoagulants (DOAC) in atrial fibrillation (AF) patients is effective and safe. However, bleeding complications still occur. Whether the measurement of DOAC levels may further improve treatment efficacy and safety is still an open issue. In the "Measure and See" (MAS) Study (#NCT03803579) venous blood was collected 15-30 days after DOAC initiation in AF patients who were then followed for one year to record the occurrence of major and clinically relevant non-major bleeding. DOAC plasma levels were measured in one laboratory, and results were kept blind to patients and treating doctors. Trough DOAC levels were assessed in 1657 patients [957 (57.7%) and 700 treated with standard and low-dose, respectively]. Fifty bleeding events were recorded during 1606 years of follow-up (3.11% pt/yrs). Fifteen bleeding events (4.97% pt/yrs) occurred in patients with C-trough standardized values in the highest activity class (> 0.50); whereas 35 events (2.69% pt/yrs) occurred in those with values in the two lower classes ( 0.50, p= 0.0401). Increasing DOAC levels and low-dose DOAC use were associated with increased bleeding risk in the first three months of treatment. 19% of patients receiving low doses had standardized activity values in the highest class. More bleeding occurred in patients treated with low (4.3% pt/yrs) than standard (2.2% pt/yrs; p= 0.0160) dose DOAC. Early measurement of DOAC levels in AF patients identified many subjects with high activity levels despite the low doses use and had more bleeding risk during the first 3 months of treatment.

DOACs use in extreme body-weighted patients: results from the prospective START-register.

BACKGROUND: Direct oral anticoagulants (DOACs) are widely used for the treatment of venous thromboembolism (VTE) and for stroke prevention in atrial fibrillation (AF). However, evidence in obese and underweight patients is limited. We assessed the safety and effectiveness of DOACs and vitamin K antagonists (VKAs) in patients ≥ 120 kg or ≤ 50 kg enrolled in an observational prospective cohort study, the START-Register. METHODS: Adult patients started on anticoagulant therapy were followed up for a median of 1.5 years (IQR 0.6-2.8). Primary efficacy outcome was the occurrence of VTE recurrence, stroke and systemic embolism. Primary safety outcome was major bleeding (MB). RESULTS: 10,080 AF and VTE patients were enrolled between March 2011 and June 2021, 295 patients weighted ≤ 50 kg and 82 patients ≥ 120 kg. Obese patients were significantly younger than underweight patients. Rates of thrombotic events were low and similar between DOACs and VKAs in underweight patients (1 event on DOACs therapy [0.9% 95% CI 0.11-5.39] and 2 on VKAs [1.1% 95% CI 0.01-47.68]) and in overweight patients (0 events on DOACs, 1 on VKAs [1.6%, 95% CI 0.11-5.79]. Two MB events occurred on DOACs (1.9%, 95% CI 0.38-6.00) and 3 on VKAs (1.6%, 95% CI 0.04-22.06) in the underweight group; 1 MB on DOACs (5.3% 95% CI 0.33-16.68) and 2 on VKAs (3.3%, 95% CI 0.02-130.77) in the overweight group. CONCLUSIONS: DOACs seem to be effective and safe also for the treatment of patients with extreme body weights, both underweight and overweight. Further prospective studies are needed to support these findings.

Venous Thromboembolism in Women of Childbearing Age: Insights from the START Registry.

BACKGROUND: Women of childbearing age are exposed to venous thromboembolic risk mainly for pregnancy and use of oral contraceptives. The impact of risk factors (RF) on venous thromboembolism (VTE) in these circumstances is still unclear. AIM: In the context of START registry, we aimed to investigate the weight of a series of RF on the occurrence of pregnancy- or combined oral contraceptive (COC)-associated VTE. MATERIALS AND METHODS: We selected all women included in the START for VTE occurred between 18-42 years and compared those with a first or recurrent pregnancy/postpartum- (group A) or COC-VTE (group B) with those who had VTE outside these circumstances (group C). Final analysis included a cohort of 532 women. Follow-up data showed that there were no significant differences between the groups in terms of thrombotic and haemorrhagic complications. As for pregnancy-associated VTE, the overall outcome was good in terms of both maternal and fetal prognosis. RESULTS: In a binary model of logistic regression, correcting for potential confounders, VTE family history conferred a significant and independent higher risk of COC-VTE compared with group C. Similarly, comparison between group A and C documented that family history significantly affected the risk of pregnancy-associated VTE. VTE in the group C was significantly associated with older age. Lastly, smoke was a significant risk factor for pregnancy/postpartum VTE when group A and group B were compared. CONCLUSION: Present data suggest that in the setting of fertile women, family history of VTE has a greater role in predicting COC- and pregnancy/postpartum- VTE than outside these circumstances.

Venous thromboembolism secondary to hospitalization for COVID-19: patient management and long-term outcomes.

Background: Venous thromboembolism (VTE) is a complication of COVID-19 in hospitalized patients. Little information is available on long-term outcomes of VTE in this population. Objectives: We aimed to compare the characteristics, management strategies, and long-term clinical outcomes between patients with COVID-19-associated VTE and patients with VTE provoked by hospitalization for other acute medical illnesses. Methods: This is an observational cohort study, with a prospective cohort of 278 patients with COVID-19-associated VTE enrolled between 2020 and 2021 and a comparison cohort of 300 patients without COVID-19 enrolled in the ongoing START2-Register between 2018 and 2020. Exclusion criteria included age <18 years, other indications to anticoagulant treatment, active cancer, recent (<3 months) major surgery, trauma, pregnancy, and participation in interventional studies. All patients were followed up for a minimum of 12 months after treatment discontinuation. Primary end point was the occurrence of venous and arterial thrombotic events. Results: Patients with VTE secondary to COVID-19 had more frequent pulmonary embolism without deep vein thrombosis than controls (83.1% vs 46.2%, P <.001), lower prevalence of chronic inflammatory disease (1.4% and 16.3%, P <.001), and history of VTE (5.0% and 19.0%, P <.001). The median duration of anticoagulant treatment (194 and 225 days, P = 0.9) and the proportion of patients who discontinued anticoagulation (78.0% and 75.0%, P = 0.4) were similar between the 2 groups. Thrombotic event rates after discontinuation were 1.5 and 2.6 per 100 patient-years, respectively (P = 0.4). Conclusion: The risk of recurrent thrombotic events in patients with COVID-19-associated VTE is low and similar to the risk observed in patients with VTE secondary to hospitalization for other medical diseases.