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PubMed1991

The effects of aprotinin on hemostatic function during cardiac surgery.

The mechanism of action by which large doses of aprotinin decrease blood loss during cardiac surgery is not completely understood. In a prospective, controlled study, 30 patients undergoing cardiac surgery were given high-dose aprotinin in accordance with a commonly used regimen. Twenty untreated but otherwise comparable patients served as the control group. The effects of aprotinin therapy during cardiopulmonary bypass on coagulation parameters, the kallikrein-kinin system, fibrinolysis, platelet stimulation, and the release of elastase from neutrophils were studied. The fibrinolysis parameters were the only measurements that showed clear and significant differences between the two groups. Aprotinin almost completely inhibited the formation of fibrin and fibrinogen degradation products. It is assumed that inhibition of systemic fibrinolysis and suppression of local fibrinolysis contribute to the hemostatic action of aprotinin. The study did not demonstrate a significant protective effect of aprotinin on platelets. In addition, the dose of aprotinin administered did not affect the kallikrein-kinin system of elastase. Therefore, these data suggest that the previously demonstrated hemostatic effects of aprotinin derive primarily from its antifibrinolytic action.

Aged↗
PubMed2006

Searching for hemostatic modifier genes affecting the phenotype of mice with very low levels of FVII.

FVII(tTA/-) mice are heterozygous for the FVII- null allele and a gene-targeted allele expressing very low levels of FVII. Approximately half the FVII(tTA/-) in a mixed C57Bl/6:129x1/SVJ background survive much longer than mice in a C57Bl/6 background, suggesting that genetic background affects the survival of mice expressing very low levels of FVII. A lineage of long-term surviving FVII(tTA/-) mice in a predominantly C57Bl/6 background was generated by selecting 16 weeks or older FVII(tTA/-) males and breeding them with C57Bl/6 FVII+/- females. It is postulated that these mice maintain 129x1/SVJ alleles at putative hemostatic modifier loci necessary for the survival of mice expressing very low levels of FVII. A SNP genomic scan was performed on DNA from long-term surviving FVII(tTA/-) mice. The scan identified 8 regions enriched for 129x1/SVJ sequences that might contain putative hemostatic modifier genes.

Animals↗
PubMed2005

Hemostatic defects in end stage liver disease.

End stage liver disease results in a complex and variably severe failure of hemostasis that predisposes to abnormal bleeding. The diverse spectrum of hemostatic defects includes impaired synthesis of clotting factors, excessive fibrinolysis, disseminated intravascular coagulation, thrombocytopenia, and platelet dysfunction. Hemostasis screening tests are used to assess disease severity and monitor the response to therapy. Correction of hemostatic defects is required in patients who are actively bleeding or require invasive procedures. Fresh frozen plasma, cryoprecipitate, and platelet transfusion remain the mainstays of therapy until larger trials confirm the safety and efficacy of recombinant factor VIIa in this population.

Blood Coagulation Disorders↗
PubMed2005

A 1-year study to compare the hemostatic effects of oral contraceptive containing 20 microg of ethinylestradiol and 100 microg of levonorgestrel with 30 microg of ethinylestradiol and 100 microg of levonorgestrel.

OBJECTIVES: To comparatively evaluate the impact of a balanced one-third dose-reduced oral contraceptive on hemostatic variables. METHODS: In an open-label, randomized study, a dose-reduced oral contraceptive containing 20 microg of ethinylestradiol (EE) and 100 microg of levonorgestrel (LNG) was compared with a reference preparation containing 30 microg of EE and 150 microg of LNG. One-year data were obtained from 48 volunteers. RESULTS: The direction and magnitude of the changes (increase or decrease) in most of the hemostatic variables were similar in both treatment groups. The majority of changes of all investigated variables remained within the reference ranges of variation. The procoagulatory variables increased to some extent from baseline to treatment cycle 13, while the anticoagulatory variables slightly decreased. In particular, thrombin turnover measured by prothrombin fragments 1+2 increased during treatment by 35% in the 20 microg of EE group and by 38% in the 30 microg of EE group. Statistically significant differences between the two treatment groups were found only for TAT. For the profibrinolytic variables, plasminogen was increased by 42% (20 microg of EE) and 49% (30 microg of EE). While the plasma levels of tPA antigen were reduced during treatment, the levels of its activity were increased by 54% (20 microg of EE) and 20% (30 microg of EE). For PAI, both antigen and activity were decreased, somewhat more pronounced with 20 microg of EE. D-Dimer remained virtually unchanged. Finally, the median FbDP levels were elevated by 30% (20 microg of EE) and 38% (30 microg of EE).

Adult↗
PubMed2006

Hemostatic response to acute physical exercise in healthy adolescents.

The chronic and immediate post-exercise responses in the hemostatic and fibrinolytic systems have been shown to be variable and reflect differing adaptations with ageing and responses to exercise protocols. This study investigated the effects of acute and exhaustive exercise on the amplitude and duration of hemostatic and fibrinolytic responses in young adolescent males. The sample comprised 10 sedentary boys (13.2+/-0.5 years, 55.8+/-11.3kg, 165.7+/-7.4cm), who had not exercised or received any medication for at least 2 weeks before the experiments. The subjects performed exhaustive stepping exercise, consisting of 1s up and down cycles to fatigue. When the subjects were unable to maintain the required stepping rhythm, they were given a 30s recovery period. Following each 30s recovery participants recommenced the stepping cadence until fatigue prevented them continuing. Venous blood samples were drawn before and immediately, 1 and 24h after exercise to assess the following coagulation and fibrinolytic parameters: Platelet counts, activated partial thromboplastin time (aPTT), prothrombin time (PT), coagulation factor VIII (FVIII:C), von Willebrand factor (vWF), fibrinogen concentration, thrombin-antithrombin complex (TAT), D-dimer, plasminogen activator inhibitor (PAI-1), and tissue-type plasminogen activator (t-PA). Immediately following exercise, platelet counts, aPTT, FVIII, vWF and t-PA were significantly elevated in contrast to PAI-1, which decreased significantly until 1h after exercise. FVIII and platelet counts were elevated at 1 and 24h after exercise, respectively. Only the parameters FVIII and PAI-1 did not return to baseline values during the first hour after physical exercise. When compared to adults the results revealed different rates and ranges of coagulation and fibrinolysis parameters being activated by exhaustive exercise in this group of adolescents.

Adolescent↗
PubMed2005

Assessment of hemostatic activation during cardiopulmonary bypass for coronary artery bypass grafting with bivalirudin: results of a pilot study.

OBJECTIVE: Bivalirudin has been successfully used as a replacement for heparin during on-pump coronary artery bypass grafting. This study was conducted to assess the effects of the currently suggested protocol for bivalirudin on hemostatic activation during cardiopulmonary bypass with and without cardiotomy suction. METHODS: Ten patients scheduled for coronary artery bypass grafting were enrolled. Bivalirudin was given with a bolus of 50 mg in the priming solution and 1.0 mg/kg for the patient, followed by an infusion of 2.5 mg . kg(-1) . h(-1) until 15 minutes before the conclusion of cardiopulmonary bypass. Cardiopulmonary bypass was performed with a closed system in 5 patients with and in 5 patients without the use of cardiotomy suction. Blood samples were obtained before and after cardiopulmonary bypass. D-dimers, fibrinopeptide A, prothrombin 1 and 2 fragments, thrombin-antithrombin, and factor XIIa were determined. RESULTS: Values for factor XIIa remained almost unchanged in both groups, indicating a minor effect of contact activation. In patients without cardiotomy suction, post-cardiopulmonary bypass values for D-dimers, fibrinopeptide A, prothrombin 1 and 2 fragments, and thrombin-antithrombin were not significantly increased compared with pre-cardiopulmonary bypass values. In patients with cardiotomy suction, values obtained for these parameters had significantly increased compared with pre-cardiopulmonary bypass values and the values obtained in the group without cardiotomy suction after cardiopulmonary bypass. CONCLUSIONS: With this protocol, hemostatic activation during cardiopulmonary bypass was almost completely attenuated when cardiotomy suction was avoided. Cardiotomy suction results in considerable activation of the coagulation system and should therefore be restricted and replaced by cell saving whenever possible.

Aged↗
PubMed2005

Effects of four different regimens of hormone replacement therapy on hemostatic parameters: a prospective randomized study.

OBJECTIVE: To compare the effects of four different regimens including oral and transdermal formulations with or without progestins on the hemostatic system in a prospective randomized fashion. METHODS: Eighty-eight women were randomized to four groups receiving continuous transdermal estradiol 50 microg/day (tE2), oral conjugated equine estrogen 0.625 mg/day (CEE 0.625 mg), oral conjugated equine estrogen 0.625 mg/day plus medroxyprogesterone acetate 2.5 mg/day (CEE 0.625 mg/MPA 2.5 mg), or oral 2 mg 17-beta estradiol combined with 1 mg norethistrone acetate (E2/norethistrone). The hysterectomized patients received only estrogen, and the remaining women received the estrogen plus progesterone combination regimens. As a marker of hemostatic system fibrinogen, tissue plasminogen activator (tPA), and plasminogen activator inhibitor-1 (PAI-1) levels were measured initially, and after 1 and 6 months of therapy. RESULTS: The treatment groups were well matched for baseline characteristics including age, height, weight, body mass index, and systolic and diastolic blood pressures. During the study period fibrinogen levels were below the baseline values in all groups. However, the decrease was only statistically significant in patients treated with oral 0.625 mg/day CEE. tPA levels were decreased significantly by tE2, CEE 0.625 mg, and CEE 0.625 mg/MPA 2.5 mg. PAI-1 levels were decreased significantly by CEE 0.625 mg, and CEE 0.625 mg/MPA 2.5 mg. When the effects of the four different regimens were compared using percentage changes from the baseline, no significant difference was found among the treatment groups. CONCLUSION: One of the treatment regimens resulted in a more coagulable state. Oral therapy with CEE decreased the levels of all parameters, and MPA did not impair this beneficial effect, except for in fibrinogen. Transdermal therapy had a minimal effect. No significant difference was noted among the four regimens.

Administration, Cutaneous↗
PubMed2005

Severe blood loss during spinal reconstructive procedures: the potential usefulness of topical hemostatic agents.

Complex spinal reconstructive procedures are invariably associated with excessive intraoperative blood loss that significantly increases the risk of severe perioperative complications. In some cases, excessive hemorrhage is equivalent to estimated total blood volume. Unfortunately, widely exposed bony surfaces are not amenable to standard hemostatic maneuvers utilized during soft tissue surgery. This article evaluates the clinical effectiveness of several approaches to blood management in this setting, and hypothesizes that underappreciated topical hemostatic agents may provide benefit by reducing the need for autologous predonation, banked donor blood or antifibrinolytic agents. Topical agents combining collagen, thrombin and fibrin have demonstrated initial promise by inducing platelet aggregation and initiating the clotting cascade when applied directly to bleeding bony sites. Clinical studies are clearly warranted.

Administration, Topical↗
PubMed2006

Hemostatic effect of activated factor VII without promotion of thrombus growth in melagatran-anticoagulated primates.

INTRODUCTION: Pharmacological enhancement of coagulation using activated prothrombin complex concentrate (APCC) or activated factor VII (FVIIa) might be useful hemostatic approaches to bleeding emergencies during anticoagulant therapy. However, any such intervention should not increase thrombotic risk. We therefore investigated their hemostatic and prothrombotic potential during propagation of large arterial-type thrombin in anticoagulated baboons. MATERIALS AND METHODS: High dose melagatran, a competitive inhibitor of thrombin (0.6 mg/kg/h), or inactivated FVIIa (FVIIai), a competitive inhibitor of FVIIa (2 mg/kg) were used for anticoagulation. APCC or FVIIa were administered to melagatran-anticoagulated animals only. Primary hemostasis was assessed as template bleeding time (BT). Thrombus formation was quantified as fibrin deposition (FD) and platelet deposition (PLD) in synthetic vascular grafts that were deployed for 40 min into arteriovenous shunts. RESULTS: Melagatran (n=11) prolonged BT to 279% (95% CI +/-140%; P<0.019), reduced FD to 33% [+/-8%; P<0.001]; and PLD to 39% [+/-11%; P<0.001] of untreated controls. FVIIai (n=3) prolonged BT (222% [+/-51%; P<0.010]) without inhibiting thrombus propagation. APCC (n=10) reduced the antithrombotic effect of melagatran (FD 52% [+/-9%; P<0.002], PLD 61% [+/-17%; P=0.028] versus melagatran alone) at a dose (250 U/kg) that had no effect on the BT (327% [+/-150%; P=0.607]. Meanwhile, FVIIa (n=12) normalized the BT to 115% (+/-32%; P<0.05) at a dose (270 microg/kg) that was not yet prothrombotic (FD 26% [+/-4%; P<0.001], PLD 39% [+/-9%; P=0.970]). CONCLUSION: Administration of FVIIa during antithrombotic treatment with direct thrombin inhibitors might support hemostasis before promoting the intraluminal expansion of thrombi.

Animals↗
PubMed2004

A simple and reliable hemostatic technique during partial nephrectomy.

INTRODUCTION: To report our experience with a refined technique for hemostasis that obviates the need for vascular control and closure of the collecting system in partial nephrectomy. TECHNICAL CONSIDERATIONS: Four to five sutures, 2 cm apart, are placed 0.5 cm from the anticipated parenchymal incision border, using a specially designed, blunt-tip, straight needle with folded 2-0 Vicryl thread. The needle is removed, leaving the Vicryl thread with the loop on one side of the kidney and two free ends on the other side. A 1.0-cm-wide Vicryl mesh strip is passed circumferentially through the loops and between the free ends on each side, tension is applied on the strip during knotting of the free ends of the thread, and the tissue is incised. No additional hemostatic sutures are necessary. No attempt is made to identify and close the open collecting system. Vascular clamping and surface cooling are avoided. Sixty-one patients have undergone this technique since 1987: initially, for complicated nephrolithiasis (n = 15), localized purulent kidney disease (n = 4), trauma (n = 3), congenital anomalies (n = 2), and resection of horseshoe kidney (n = 6) and, recently, for peripherally located renal tumor (n = 31). Upper pole resection was performed in 11 patients, lower pole resection in 45, and middle segment resection in 5. The blood loss was minimal, with only 1 patient developing gross hematuria that resolved after conservative treatment. No other complications occurred. CONCLUSIONS: A simple and easily performed hemostatic method suitable for peripherally located and, particularly, polar renal tumors is described. The Vicryl mesh strip prevents tears of the parenchymal sutures and ensures good hemostasis without closing the collecting system separately.

Hemostasis, Surgical↗
PubMed1997

Effects of hormone-replacement therapy on hemostatic factors, lipid factors, and endothelial function in women undergoing surgical menopause: implications for prevention of atherosclerosis.

Women with premature menopause are at high risk for vascular compications associated with thrombogenesis and atherogenesis. The use of hormone-replacement therapy (HRT), however, may protect against these complications. Hemostatic abnormalities and endothelial function are closely related to the processes of thrombogenesis and atherogenesis. The purpose of the study was to evaluate the effects of premature menopause on markers of hemostasis, platelet function, and endothelial function and the effects of starting HRT. This is a prospective longitudinal study of premenopausal women undergoing surgical menopause in whom estrogen HRT is started. We measured sequential changes in plasma levels of the hemostatic factors (fibrinogen, fibrin D-dimer, and plasminogen activiator inhibitor [PAI]), markers of platelet function (soluble leukocyte adhesion molecule P-selectin) and endothelial function (von Willebrand factor [vWf], soluble thrombomodulin [sTM], and tissue plasminogen activator [TPA]), and serum lipid levels, including lipoprotein A. Twenty-seven premenopausal women (mean age 43.6 +/- 6.5 years) undergoing hysterectomy and bilateral salpingo-oophrectomy were studied. In the postsurgical menopausal state (visit 2), there was a significant elevation in sTM levels (paired Wilcoxon test, p = 0.008). There was also a trend toward higher median soluble P-selectin, PAI, and mean TPA levels and lower vWf levels. After 6 weeks of HRT (visit 3), there was a significant reduction in mean vWf (paired Wilcoxon test, p = 0.0026), sTM (p = 0.039), and TPA levels (p = 0.02) compared with premenopausal levels. There were no significant changes in plasma fibrinogen, fibrin D-dimer, and PAI levels at visit 2 or visit 3 compared with premenopausal levels. There was a significant increase in serum lipoprotein A (paired Wilcoxon test, p = 0.008), cholesterol, and triglyceride levels after surgical menopause (paired t test, p < 0.01). Lipoprotein A and cholesterol levels after HRT (visit 3) were not significantly different from prehysterectomy levels, although triglyceride levels were increased further. HRT results in a significant reduction in vWf, sTM, and TPA levels, suggesting beneficial effects on endothelial function and atherogenesis. Although there was a significant increase in serum lipoprotein A and cholesterol levels after surgical menopause, lipoprotein A and cholesterol levels after HRT were not significantly different from presurgery levels. These observations are consistent with the beneficial effects of HRT in cardiovascular hemodynamics and cardiovascular disease.

Adult↗
PubMed1997

Association of hemostatic factors with peripheral vascular disease.

Hemostatic risk factors have been well established in coronary artery disease but less well studied in peripheral vascular disease. The relationship of coagulation and fibrinolytic proteins to lower limb arterial occlusive disease and other vascular risk factors remains poorly defined. Fibrinogen, factor VII coagulant activity, von Willebrand factor (vWf) antigen, and plasminogen activator inhibitor-1 (PAI-1) activity were measured in 46 adult participants in the Arterial Disease Multiple Intervention Trial (ADMIT) and in 76 control subjects and related to ankle-brachial systolic pressure index (ABI), a measure of lower limb arterial stenosis. The primary inclusion criterion for the ADMIT study population was an average of two ABIs <0.85. Fibrinogen and PAI-1 in ADMIT subjects were significantly higher than in control subjects (331 +/- 52 mg/dl vs 273 +/- 46 mg/dl, p < 0.0001; 18.7 +/- 10 units/ml vs 13.5 +/- 8.9 units/ml, p < 0.04). There were significant correlations of fibrinogen with ABI, factor VII coagulant activity, and systolic and diastolic blood pressures; PAI-1 with body mass index and age; and factor VII coagulant activity with cholesterol levels. Logistic regression analysis, considering hemostatic variables and several known nonhemostatic risk factors of peripheral arterial disease, showed that fibrinogen and systolic blood pressure were independently associated with ABI status in this population. The results demonstrate a strong independent correlation between fibrinogen levels and the presence of lower limb arterial stenosis. PAI-1 levels were elevated in ADMIT participants, but multivariate analysis did not demonstrate an independent relationship between PAI-1 and ABI.

Aged↗
PubMed1998

Atherogenic, hemostatic, and other potential risk markers in subjects with previous isolated myocardial infarction compared with long-standing uncomplicated stable angina.

BACKGROUND: Several atherogenic, hemostatic, inflammatory, and genetic parameters and markers have been implicated as risk factors in coronary artery disease, although whether they are risk factors for acute as opposed to chronic coronary disease is unclear. METHODS AND RESULTS: Fifty subjects with an isolated myocardial infarction >3 months previously were compared with 50 subjects with a minimum 3-year history of stable angina, documented coronary artery disease, normal electrocardiogram and normal ventricular wall motion, and no episode suggesting infarction or unstable angina. Biologic variables analyzed included apolipoprotein B (apo B), lipoprotein (a), C-reactive protein (CRP), fibrinogen, factor VII, tissue plasminogen activator (TPA) and inhibitor (PAI-1), thrombin-antithrombin (TAT), fragment 1+2 (F1+2), von Willebrand factor (vWF), activated protein C resistance, homocyst(e)ine, anticardiolipin antibodies, blood group, and the angiotensin-converting enzyme insertion/deletion (I/D) and angiotensin II receptor gene polymorphisms. There were no significant differences between the 2 groups for any of the variables studied, although fibrinogen and F 1+2 tended to be slightly higher in the angina group (P = .09 for each). These significant correlations were present: age with fibrinogen, homocyst(e)ine, and vWF; factor VII with apo B, homocyst(e)ine, and TPA; apo B with TPA and CRP; CRP with fibrinogen, TPA, PAI-1, and factor VII; fibrinogen with vWF. CONCLUSIONS: Examination of atherogenic, hemostatic, inflammation, and genetic variables in the clinically quiescent state permitted no distinction between subjects with a previous isolated myocardial infarction in contrast to those with long-standing uncomplicated stable angina, favoring the notion that acute coronary events occur at random on a varying background of atherosclerosis. The multiple correlations found among these variables also underscore their complex interaction in the atherosclerotic process.

Adult↗
PubMed1999

Electrophysiologic procedures and activation of the hemostatic system.

BACKGROUND: Thromboembolism occurs in 0.4% to 2% of the subjects undergoing radiofrequency ablation (RFA), but its mechanisms remain unclear. Our aim was to evaluate several parameters of the hemostatic system in relation to the electrophysiologic procedure. METHODS: Thirty consecutive patients were enrolled in the study. Fifteen underwent electrophysiologic study and 15 underwent radiofrequency ablation. Before the ablation procedure, all subjects were given an intravenous heparin bolus (2500 IU). Blood samples were drawn immediately before, at the end of, and 24 hours after the procedures. Spontaneous platelet aggregation in whole blood and in platelet-rich plasma, markers of clotting activation (prothrombin fragment 1+2 and the thrombin-antithrombin complex) and the fibrinolytic system (plasminogen activator inhibitor and D-dimer) levels were evaluated. RESULTS: At the end of the procedure, spontaneous platelet aggregation in whole blood, prothrombin fragment 1+2, thrombin-antithrombin complex, and D-dimer levels increased significantly in all patients. The hemostatic changes were more marked after RFA than after electrophysiology. Spontaneous aggregation in whole blood, prothrombin fragment 1+2, and thrombin-antithrombin complex levels at 24 hours after the procedure were similar to those observed before the procedure in both groups; D -dimer levels were still elevated with respect to preprocedure levels, with a trend toward higher levels in patients undergoing RFA rather than electrophysiology. A significantly more marked activation of coagulation (prothrombin fragment 1+2, P <.005) was found in patients in whom the mean duration of energy application was higher than 23.5 seconds. CONCLUSIONS: Our data suggest that antithrombotic prevention with a prolonged administration of heparin and/or the association of antiplatelet agents should be considered in patients undergoing RFA.

Adult↗
PubMed2003

Relation of levels of hemostatic factors and inflammatory markers to the ankle brachial index.

Associations between hemostatic and inflammatory markers relative to the ankle brachial index (ABI), an indicator of the presence and severity of peripheral arterial disease (PAD), are not fully understood. We studied relations among selected hemostatic factors, inflammatory markers, and the ankle brachial index (ABI) in patients with and without peripheral arterial disease (PAD). Participants were 370 men and women with ABI <0.90 and 231 patients with ABI 0.90 to 1.50 identified from noninvasive vascular laboratories and general medicine practice. Blood factors were D-dimer, prothrombin 1.2, tissue plasminogen activator (t-PA) antigen, plasminogen activator inhibitor-1 (PAI-1), and inflammatory markers (high-sensitivity C-reactive protein [CRP], fibrinogen, and serum amyloid A [SAA]). Among patients without a history of cardiac or cerebrovascular disease, the ABI was significantly inversely associated with log D-dimer (p <0.001), log prothrombin 1.2 (p = 0.001), log CRP (p <0.001), and log fibrinogen (p = 0.005) in unadjusted analyses. In multivariable regression analyses adjusting for all blood factors as well as potential confounders, D-dimer was associated independently with ABI in participants with a history of cardiac or cerebrovascular disease (p = 0.003) and in participants without a history of cardiac or cerebrovascular disease (p = 0.017). In these analyses, CRP was associated independently with ABI among participants with a history of cardiac or cerebrovascular disease (p = 0.026). CRP was not associated independently with ABI in participants without a history of cardiac or cerebrovascular disease. We conclude that D-dimer levels may be more sensitive than other blood markers for measuring the extent of atherosclerosis in lower extremity arteries.

Aged↗
PubMed2000

Immediate effect of balloon valvuloplasty on hemostatic changes in mitral stenosis.

This study was conducted to assess right and left atrial hemostatic function in patients with mitral stenosis (MS) and to investigate the immediate effect of balloon mitral valvuloplasty (BMV) on hemostatic function. BMV was performed in 28 patients with MS (age 29 +/- 8 years) who had sinus rhythm and no left atrial (LA) thrombus. Right and left atrial biochemical markers of platelet activity (platelet factor 4 [PF4] and B thromboglobulin [BTG]), coagulation (thrombin-antithrombin III complex [TAT]), and fibrinolytic activity (D-dimer) were measured before and 30 minutes after BMV. Right atrial levels of these markers were also measured in 20 control subjects. Compared with control subjects, patients with MS had higher right atrial levels of PF4 (30 +/- 15 vs 5 +/- 2 IU/ml), BTG (231 +/- 53 vs 30 +/- 8 IU/ml), TAT (7 +/- 4 vs 2 +/- 0.3 microg/L), and D-dimer (380 +/- 145 vs 160 +/- 35 ng/ml, p < 0.0001 in all). TAT levels were higher in the left atrium than in the right atrium of patients before BMV (8 +/- 4 vs 7 +/- 4 microg/L, p < 0.0001). BMV was successful (final mitral valve area > or = 1.5 cm2 and > or = 50% increase of the initial valve area) in all patients. There was a significant reduction of LA levels of PF4 (35 +/- 8 to 26 +/- 9 IU/ml, p < 0.0001), BTG (225 +/- 41 to 196 +/- 28 IU/ml, p < 0.001), and TAT (10 +/- 5 to 7 +/- 1 microg/L, p < 0.05) in the 16 patients with LA pressure < 10 mm Hg after BMV, whereas these markers were not reduced in the 12 patients with left atrial pressure > or = 10 mm Hg after BMV. These data indicate that platelet function, coagulation status, and fibrinolytic activity are increased regionally in the left atrium and in the systemic circulation in patients with MS and sinus rhythm in the absence of LA thrombus. Successful BMV induces a significant reduction of prethrombotic status in patients with low LA pressure after the procedure. Patients with high LA pressure after BMV maintain a high prethrombotic state and may be considered at an increased risk of thromboembolism after the procedure.

Adolescent↗
PubMed1999

The effects of a low-dose monophasic preparation of levonorgestrel and ethinyl estradiol on coagulation and other hemostatic factors.

OBJECTIVE: This study was undertaken to evaluate the effects on hemostatic factors of a low-dose preparation of levonorgestrel and ethinyl estradiol in a 12-cycle study. STUDY DESIGN: Thirty healthy women began taking 100 microg levonorgestrel and 20 microg ethinyl estradiol on the first day of the menstrual cycle, continued to take the preparation for the next 21 days, and then took placebo for 7 days. Mean changes in prothrombin time, partial thromboplastin time, and levels of factors VII and X, antithrombin, plasminogen, fibrinogen, protein S, thrombin-antithrombin complexes, and D-dimer were analyzed at baseline and at cycles 3, 6, and 12 with paired Student t tests. RESULTS: Factor X, plasminogen antigen and activity, and D-dimer levels were significantly increased (P </=.01) during all 3 cycle periods. Antithrombin antigen and protein S total antigen levels were significantly (P </=.001 ) decreased at cycles 3, 6, and 12, whereas factor VII and protein S activity levels were significantly (P </=.05) decreased at cycle 3 and at cycles 3 and 6, respectively. CONCLUSION: The effects on hemostatic factors in healthy women of a monophasic preparation of 100 microg levonorgestrel and 20 microg ethinyl estradiol were similar to those of other low-dose oral contraceptives.

Adult↗
PubMed1999

High prevalence of hemostatic abnormalities in women with a history of severe preeclampsia.

OBJECTIVE: In patients with a history of severe preeclampsia, an increased frequency of hemostatic abnormalities has recently been suggested in small studies without control groups. Our purpose was to investigate the prevalence of such abnormalities in a large patient group with a history of severe hypertensive disorder in pregnancy, in comparison with an appropriate control group. STUDY DESIGN: A total of 345 patients with a history of severe preeclampsia were investigated at a minimum of 10 weeks post partum for the presence of activated protein C resistance, the associated factor V mutation, hyperhomocysteinemia and anticardiolipin antibodies. The control group consisted of 67 healthy women with a history of uncomplicated pregnancies only. Blood was obtained during the second half of a normal menstrual cycle, and none of the patients or control subjects used oral contraceptives. RESULTS: Of all patients, 11.3% had activated protein C resistance (control subjects 1.5%, P =.025). Only half of these patients had the factor V mutation. Hyperhomocysteinemia was present in 12.1% of all patients, in comparison with 4.5% in the control group (P =.115). Anticardiolipin antibodies were observed in 20.9% of the patients, whereas these antibodies were found in 7.5% of the control subjects (P =.016). In general, the prevalence of these abnormalities was 1.5 to 2 times higher in patients who were delivered before 28 weeks, in comparison with patients who were delivered after 28 weeks. CONCLUSIONS: Hemostatic abnormalities, associated with an increased risk of thrombosis, are present in approximately 40% of patients with a history of severe preeclampsia, which is almost 4 times higher than in control subjects. These findings might suggest a cause of preeclampsia and could have implications in subsequent pregnancies and general health.

Antibodies, Anticardiolipin↗