Risk stratification and outcomes in hemodynamically stable patients with acute pulmonary embolism: a prospective, multicentre, cohort study with three months of follow-up.

BACKGROUND: The role of risk stratification in normotensive patients with acute pulmonary embolism (PE) is still unclear. OBJECTIVES: We evaluated, in these patients, the usefulness of six prognostic markers for predicting in-hospital adverse events related to PE and 3-month mortality. PATIENTS/METHODS: Two hundred and one consecutive patients with confirmed acute PE and normal blood pressure, who were administered conventional anticoagulation, were recruited in a multicentre prospective cohort study with 3 months of follow-up. At baseline, they received a comprehensive risk-evaluation including echocardiographic assessment of right ventricular dysfunction, determination of troponin I, brain natriuretic peptide and D-dimer, arterial blood gas analysis and a clinical score. Primary outcome of the study was PE-related in-hospital death or clinical deterioration. Secondary outcomes were in-hospital and 3-month all-cause mortality. RESULTS: The primary outcome occurred in one patient (0.5%), who died from PE during hospitalization. The in-hospital and 3-month all-cause mortality were 2% and 9%, respectively. None of the prognostic markers was predictive of the primary outcome. Clinical score, troponin I and hypoxemia predicted in-hospital all-cause mortality (P = 0.02, 0.01 and < 0.01, respectively). Clinical score (HR, 4.7; 95% CI, 1.9-12.0), D-dimer (4.8; 1.4-16.3), hypoxemia (5.7; 2.1-15.1) and troponin I (7.5; 2.5-22.7) were predictors of 3-month all-cause mortality on univariate analysis. On multivariate analysis clinical score and troponin I remained independently predictive. CONCLUSIONS: We did not find prognostic markers useful as predictors of in-hospital PE-related adverse events. Clinical score, troponin I and hypoxemia predicted in-hospital all-cause mortality. Clinical score and troponin I independently predicted 3-month all-cause mortality.

Transcriptional up-regulation of PHLDA1 by 17beta-estradiol in MCF-7 breast cancer cells.

Most breast cancer risk factors are associated with prolonged exposure of the mammary gland to high levels of estrogens. The actions of estrogens are predominantly mediated by two receptors, ERalpha and ERbeta, which act as transcription factors binding with high affinity to estrogen response elements in the promoter region of target genes. However, most target genes do not contain the consensus estrogen response elements, but rather degenerated palindromic sequences showing one or more mutations and other ER-binding sites such as AP-1 and SP-1. Using the differential display reverse transcription-polymerase chain reaction technique, our group identified several genes differentially expressed in normal tissue and in ER-positive and ER-negative primary breast tumors. One of the genes shown to be down-regulated in breast tumors compared to normal breast tissue was the PHLDA1 (Pleckstrin homology-like domain, family A, member 1). In the present study, we investigated the potential of PHLDA1 to be regulated by estrogen via ER in MCF-7 breast cancer cells. The promoter region of PHLDA1 shows an imperfect palindrome, an AP-1- and three SP-1-binding sites potentially regulated by estrogens. We also assessed the effects of 17beta-estradiol on PHLDA1 mRNA expression in MCF-7 breast cancer cells. MCF-7 cells exposed to 10 nM 17beta-estradiol showed more than 2-fold increased expression of the PHLDA1 transcripts compared to control cells (P = 0.05). The anti-estrogen ICI 182,780 (1 microM) inhibited PHLDA1 mRNA expression and completely abolished the effect of 10 nM 17beta-estradiol on PHLDA1 expression (P < 0.05), suggesting that PHLDA1 is regulated by estrogen via ER.

Transcriptional up-regulation of PHLDA1 by 17â-estradiol in MCF-7 breast cancer cells

Most breast cancer risk factors are associated with prolonged exposure of the mammary gland to high levels of estrogens. The actions of estrogens are predominantly mediated by two receptors, ERá and ERâ, which act as transcription factors binding with high affinity to estrogen response elements in the promoter region of target genes. However, most target genes do not contain the consensus estrogen response elements, but rather degenerated palindromic sequences showing one or more mutations and other ER-binding sites such as AP-1 and SP-1. Using the differential display reverse transcription-polymerase chain reaction technique, our group identified several genes differentially expressed in normal tissue and in ER-positive and ER-negative primary breast tumors. One of the genes shown to be down-regulated in breast tumors compared to normal breast tissue was the PHLDA1 (Pleckstrin homology-like domain, family A, member 1). In the present study, we investigated the potential of PHLDA1 to be regulated by estrogen via ER in MCF-7 breast cancer cells. The promoter region of PHLDA1 shows an imperfect palindrome, an AP-1- and three SP-1-binding sites potentially regulated by estrogens. We also assessed the effects of 17â-estradiol on PHLDA1 mRNA expression in MCF-7 breast cancer cells. MCF-7 cells exposed to 10 nM 17â-estradiol showed more than 2-fold increased expression of the PHLDA1 transcripts compared to control cells (P = 0.05). The anti-estrogen ICI 182,780 (1 µM) inhibited PHLDA1 mRNA expression and completely abolished the effect of 10 nM 17â-estradiol on PHLDA1 expression (P < 0.05), suggesting that PHLDA1 is regulated by estrogen via ER.

Relation between quality of anticoagulant treatment and the development of the postthrombotic syndrome.

BACKGROUND: About 30% of patients with an episode of adequately treated deep venous thrombosis (DVT) develop the postthrombotic syndrome (PTS) within 2 years. During treatment with vitamin K antagonists (VKA) patients spend only 60% of time between an International Normalized Ratio (INR) of 2.0 and 3.0. We hypothesized that patients who spend a large amount of their time beneath this range will have an increased risk of the PTS. OBJECTIVE: To investigate the relation between the quality of anticoagulant therapy with VKA and the risk of the development of the PTS. METHODS: The time spent beneath the therapeutic range was calculated for patients with a first episode of DVT, who were treated with VKA for at least 3 months. At follow-up assessments for a maximum of 5 years, presence and severity of signs and symptoms of PTS were recorded. RESULTS: A total of 244 patients, with a median duration of follow-up of 4.9 years were included for analysis. Of these, 81 patients (33%) developed the PTS. The multivariate model showed that patients who spend more than 50% of their time beneath an INR level of 2.0 are at higher risk for PTS [odds ratio (OR): 2.71, 95% CI: 1.44-5.10]. CONCLUSIONS: Low quality treatment with VKA, which is a common condition, is related to the occurrence of the PTS in patients with DVT. Strategies aimed at improving the quality of long-term anticoagulation might have the potential to reduce the incidence of this complication.

The optimal treatment of venous thrombosis: current status and future perspectives.

Acute deep venous thrombosis (DVT) of the lower extremities is a serious and potentially fatal disorder, which often complicates the course of hospitalized patients but may also affect ambulatory and otherwise healthy people. Venous thrombosis is uncommon in young individuals and becomes more frequent with advancing age. The clinically important problems associated with venous thrombosis are death from pulmonary embolism, morbidity resulting from the acute event, recurrent venous thromboembolic events, the post-thrombotic syndrome, and the inconvenience and side-effects of investigations and treatment. The main objectives of treatment of DVT are prevention of (both fatal and nonfatal) pulmonary embolism and thrombus extension in the acute phase of the disease, prevention of recurrences of venous thromboembolism in the months following the acute episode, and prevention of late sequelae (post-thrombotic syndrome). These objectives are satisfactorily achieved with anticoagulant drugs (heparin and vitamin K antagonists), which therefore are the mainstays of DVT treatment. Other therapeutic options have a more limited application.

Upper extremity deep vein thrombosis: risk factors, diagnosis, and management.

Upper extremity deep vein thrombosis (UEDVT) should no longer be regarded as an uncommon and benign disease, as previously reported. It is usually associated with risk factors, as central venous lines, malignancy, and coagulation defects; however, up to 20% of UEDVTs are apparently spontaneous. The clinical picture is characterized by swelling, pain, and functional impairment, albeit UEDVT may be completely asymptomatic. Objective testing is mandatory prior to instituting anticoagulation because the prevalence of UEDVT is less than 50% in symptomatic subjects, and compression ultrasound or color Doppler represents the preferred diagnostic methods. Up to 36% of the patients develop pulmonary embolism, which may be fatal; postthrombotic sequelae and recurrent thromboembolism are also frequent complications. Unfractionated or low-molecular-weight heparin followed by oral anticoagulation should be regarded as the treatment of choice; thrombolysis and surgery may be indicated in selected cases. Prophylaxis with low-dose heparin or low-dose warfarin is necessary whenever central venous catheters are positioned.

Congenital deficiencies and abnormalities of prothrombin.

Prothrombin (factor II) deficiency was first described in 1947 by Quick et al., although the first prothrombin abnormality was reported in 1969 by Shapiro et al. The condition is still considered very rare. In spite of its rarity, the defect has allowed important improvements in our understanding of both congenital and acquired prothrombin deficiencies. The diagnosis of prothrombin deficiency or abnormality can be made using a combination of clotting, chromogenic and immunological assays. In cases of true deficiency, a parallel decrease in all these assays is observed, regardless of the activating agent. If discrepancies among the clotting assays are noted, particularly using viper venoms, a dysprothrombinemia should be suspected. Usually, activity levels less than 10% of normal are found in homozygotes, and between 40 and 60% in heterozygotes. Factor II levels in congenital dysprothrombinemias are more variable since one may encounter homozygotes, heterozygotes and compound heterozygotes between a heterozygous abnormality and heterozygous 'true' deficiency or between two distinct abnormalities. Usually the levels of factor II vary between 1 and 50% of normal. Antigen levels in congenital dysprothrombinemias will be normal, near normal or slightly decreased but always higher than the clotting counterpart. Cases with a parallel decrease in prothrombin activity and antigen should not be considered as examples of hypoprothrombinemia. The gene involved in the synthesis of prothrombin is located in chromosome 11. It is composed of 10 exons and 8 introns. Molecular biology studies have discovered several point mutations in some of the dysprothrombinemias. Bleeding manifestations may be severe in homozygous 'true' deficiency and may be more variable in dysprothrombinemias. Heterozygotes are usually asymptomatic. Prognosis is variable and generally in agreement with the prothrombin activity level. In homozygous true deficiency, hemarthroses and intracranial bleeding have been described. Substitution therapy is based on the administration of prothrombin complex concentrates or of plasma. The long half-life of prothrombin injected, about 70 h, allows the achievement of hemostatically effective levels (about 50% of normal) without difficulty.

Use of an algorithm for administering subcutaneous heparin in the treatment of deep venous thrombosis.

BACKGROUND: Despite the widespread use of subcutaneous heparin in the initial treatment of deep venous thrombosis, there are no guidelines for achieving adequate anticoagulation with this drug. OBJECTIVE: To implement a weight-based algorithm for the administration of subcutaneous unfractionated heparin after an intravenous loading dose. DESIGN: Prospective cohort study. SETTING: University hospital. PARTICIPANTS: 70 outpatients with proximal venous thrombosis. INTERVENTION: An intravenous bolus of heparin followed by a subcutaneous injection of heparin in doses adjusted for body weight. Subsequent adjustments of the subcutaneous heparin dose were scheduled twice daily according to the algorithm; the activated partial thromboplastin time (aPTT) was measured in the mid-interval (target range, 50 to 90 seconds). RESULTS: The therapeutic threshold aPTT (> or = 50 seconds) was achieved in 61 patients (87%) within 24 hours and in 69 patients (99%) within 48 hours. In 7 patients (10%), a supratherapeutic aPTT lasted more than 12 hours. No major bleeding episodes or cases of heparin-induced thrombocytopenia were seen. Three patients (4.3% [95% CI, 0.9% to 12.0%]) had recurrent thromboembolism during 3 months of follow-up. CONCLUSION: The administration of subcutaneous heparin according to a weight-based algorithm allows the rapid achievement of effective and safe anticoagulation in patients with deep venous thrombosis.

Hemorrhagic and thrombotic disorders due to factor V deficiencies and abnormalities: an updated classification.

The recent description of a factor V abnormality (factor V Leiden) associated with an increased incidence of thrombosis has considerably increased interest in this clotting factor. The discovery of this new clinical entity indicated the need for an updated classification of factor V defects. These should be divided into hemorrhagic and thrombotic disorders. A proper classification of hemorrhagic disorders should include: 1) homozygous and heterozygous 'true' factor V deficiency; and 2) combined factor V and factor VIII deficiencies. The latter should be subdivided in Type I (association type) and Type II (common defect). A suitable classification of the thrombotic factor V defects should include: 1) homozygous and heterozygous factor V Leiden; and 2) combined heterozygous factor V Leiden and heterozygous 'true' factor V deficiency. The presence of thrombosis in these latter patients, often as severe as those seen in homozygous patients with activated protein C (APC) resistance, allows important considerations on the functions of factor V. It would seem that half the normal level of factor V activity and antigen is unable to protect against thrombosis in patients with heterozygous APC resistance. An accurate evaluation of factor V activity and antigen is indicated in all patients with suspected factor V defects. The first suspicion may be obtained by the presence of a mild prolongation of prothrombin time and of partial thromboplastin time. The suspicion should then be immediately confirmed by specific factor V activity and antigen assays. This approach is of great importance even for the presumptive diagnosis of pseudohomozygosis for APC resistance. In fact, in these cases, factor V activity is about 50% of normal, whereas factor V antigen is 100% of normal. In heterozygous 'true' factor V deficiency both activity and antigen are about 50% of normal.

The clinical course of deep-vein thrombosis. Prospective long-term follow-up of 528 symptomatic patients.

BACKGROUND AND OBJECTIVE: In contrast to the extensive documentation on the short-term outcome of patients with acute deep vein thrombosis (DVT) of the lower extremities, little is known about the long-term clinical course of this disease. To determine the clinical course of patients with a first episode of symptomatic DVTn over an 8-year follow-up period. The primary aims were to assess the long-term incidence of recurrent venous thromboembolism and that of the post-thrombotic syndrome. In addition, we determined mortality and evaluated potential risk factors for all these outcomes. METHODS: This was designed as a prospective cohort follow-up study. Consecutive symptomatic outpatients with a first episode of venography proven DVT were treated with an initial course of full-dose (low molecular weight) heparin, followed by at least three months of oral anticoagulants. After discharge, they were instructed to wear compression elastic stockings for at least two years. Follow-up assessments were scheduled at three and six months, and then every six months up to eight years. Diagnosis of recurrent venous thromboembolism was made according to standard criteria. The presence of post-thrombotic syndrome was evaluated using a standardized scale. RESULTS: A total of 528 consecutive patients with a first episode of venography confirmed DVT were included in the study. The cumulative incidence of recurrent venous thromboembolism after two, five and eight years was 17.2, 24.3 and 29.7%, respectively. Malignancy and impaired coagulation inhibition increased the risk of recurrent venous thromboembolism (RR = 1.48 and 2.0, respectively). In contrast, surgery and recent trauma or fracture were associated with a diminished risk of recurrent venous thromboembolism (RR = 0.65 and 0.39, respectively). The cumulative incidence of post-thrombotic syndrome after two, five and eight years was 24.5, 29.6 and 29.8%, respectively. The development of ipsilateral recurrent DVT was strongly associated with the risk for post-thrombotic syndrome (risk ratio, 2.4). Survival after eight years was 69%. The presence of malignancy increased the risk of death remarkably (risk ratio, 7.1). INTERPRETATION AND CONCLUSIONS: Symptomatic DVT carries a high risk for recurrent venous thromboembolism that persists for many years, especially in patients without transient risk factors for DVT. The post-thrombotic syndrome occurs in almost one-third of patients and is strongly related to recurrent ipsilateral DVT. Our findings challenge the widely adopted short course of anticoagulation in patients with symptomatic DVT.

A novel dysfunctional protein C (protein C Padua 2) associated with a thrombotic tendency: substitution of Cys for Arg-1 results in a strongly reduced affinity for binding of Ca++.

A dysfunctional protein C (PC) molecule (Protein C Padua 2) was found in a 40-year-old man presenting with recurrent deep vein thrombosis/pulmonary embolism and a family history of thrombotic disease. The patient exhibited a normal PC antigen level, normal chromogenic activity (using Protac as PC activator) but markedly reduced coagulometric activity. After adsorption of patient plasma onto Al(OH)3, between 30% and 45% PC antigen/chromogenic activity but no coagulometric activity was detectable in the supernatant. The dysfunctional molecule exhibited reduced affinity for a Ca++ dependent anti-protein C monoclonal antibody as detected by specific ELISA assay. Immunoblotting experiments showed that PC Padua 2 had an increased MW (95 kD v 65 kD for normal PC). The lesion responsible was determined by PCR/direct sequencing to be a heterozygous CGT/TGT transition in exon 3 of the protein C gene resulting in the substitution of Arg by Cys at residue--1 in the pro-peptide leader sequence. The presence of a high MW PC was consistent with the fact that (part of) the propeptide (at least Cys-1) still was attached to the protein C molecule. This finding could also explain the strongly reduced affinity of PC Padua 2 for the Ca++ dependent anti-protein C monoclonals.