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R Quintavalla

Publications and source records attributed to R Quintavalla.

At least 19 recordsLinked to original sources
PubMed1999

Pre-operative plasma levels of soluble fibrin polymers correlate with the development of deep vein thrombosis after elective neurosurgery.

The role of blood tests in identifying patients at high risk for post-operative venous thromboembolism is undefined. The aim of this study was to evaluate the correlation between pre-operative plasma levels of soluble fibrin polymers (SFP), as determined by a recently developed enzyme-linked immunosorbent assay (ELISA) assay (TpP), and the incidence of deep vein thrombosis (DVT) after elective neurosurgery. Blood samples for SFP assay were withdrawn on the day before surgery from 157 consecutive patients undergoing elective neurosurgery for brain or spinal tumour. Patients were randomized to subcutaneous enoxaparin (40 mg once daily) or placebo given for at least 7 days. All patients wore compression stockings. DVT was assessed by bilateral venography, performed on day 8 +/- 1. Thirty-four patients (21.7%) were found to have a DVT, proximal in 11 (7%) and isolated distal in 23. Patients with and without DVT had a plasma pre-operative SFP levels of 6.2 +/- 4.6 and 1.9 +/- 1.5 mg/ml respectively (mean +/- SD) (P < 0.001). SFP levels in patients with proximal and isolated distal DVT were 7.6 +/- 5.1 and 5.5 +/- 4.4 microg/ml, respectively (P = 0.22). SFP cut-off levels categorized patients into three classes of DVT incidence. The incidence of DVT was 7.4% (6 of 81) for SFP levels < 2 microg/ml, 20.4% (11 of 54) for levels between 2 and 4.5 microg/ml, and 77.3% (17 of 22) for levels > 4.5 microg/ml (P= 0.001, Cochran-Mantel-Haenszel test). We conclude that pre-operative SFP levels correlate with post-operative DVT in elective neurosurgery patients. Further studies are required to define whether pre-operative SFP measurement could be useful in patient management.

Adult↗
PubMed1999

Risk of venous thromboembolism and clinical manifestations in carriers of antithrombin, protein C, protein S deficiency, or activated protein C resistance: a multicenter collaborative family study.

Deficiencies of antithrombin (AT), protein C (PC) or protein S (PS), and activated protein C resistance (APCR) are very well-established coagulation defects predisposing to venous thromboembolism (VTE). We performed a retrospective cohort family study to assess the risk for VTE in individuals with AT, PC, or PS deficiency, or APCR. Five hundred thirteen relatives from 9 Italian centers were selected from 233 families in which the proband had had at least 1 episode of VTE. We calculated the incidence of VTE in the whole cohort and in the subgroups after stratification by age, sex, and defect. The overall incidence of VTE (per 100 patient-years) in the group of relatives was 0.52. It was 1.07 for AT, 0.54 for PC, 0.50 for PS, 0.30 for APCR, and 0.67 in the group with a double defect. The incidence was associated with age, but not with sex. The mean age at onset was between 30 and 40 years for all the coagulation defects. Women had the peak of incidence in the age range of 21 to 40 years, earlier than men. The lifetime risk for VTE was 4.4 for AT versus APCR, 2.6 for AT versus PS, 2.2 for AT versus PC, 1.9 for PC versus APCR, and 1.6 for PS versus APCR. AT deficiency seems to have a higher risk for VTE than the other genetic defects. There is a relation between age and occurrence of thrombosis for both men and women. The latter had the peak of incidence earlier than the former.

Activated Protein C Resistance↗
PubMed1994

Low molecular weight heparin versus warfarin in the prevention of recurrences after deep vein thrombosis.

To evaluate the role of low-molecular weight heparin (LMWH) as an alternative to oral anticoagulants in the prevention of recurrent venous thromboembolism, we compared in a randomized trial conventional warfarin treatment with a three-month course of enoxaparin 4000 anti-Xa units once a day subcutaneously. 187 patients with symptomatic deep-vein thrombosis (DVT), diagnosed by strain-gauge plethysmography plus D-dimer latex assay and confirmed by venography in most cases, were treated with full-dose subcutaneous heparin for ten days and then randomized to secondary prophylaxis. During the 3-month treatment period, 6 of the 93 patients who received LMWH (6%) and 4 of the 94 patients on warfarin (4%) had symptomatic recurrence of venous thromboembolism confirmed by objective testing (p = 0.5; 95% confidence interval [CI] for the difference, -3% to 7%). Four patients in the LMWH group had bleeding complications as compared with 12 in the warfarin group (p = 0.04; 95% CI for the difference, 4% to 14%). In the 9-month follow-up period, during which 34 patients on warfarin prolonged treatment for other 3 months and 14 up to one year, 10 patients in the enoxaparin group and 4 patients in the warfarin group suffered a documented recurrence of venous thromboembolism. Of these 14 late recurrences, just one occurred in patients with postoperative DVT. After one year there were 16 recurrences (17%) in the LMWH group and 8 (9%) in the warfarin group (p = 0.07; 95% CI for the difference, 1% to 16%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

A comparative study on the quality of oral anticoagulant therapy (warfarin versus acenocoumarol).

In our Center for the Surveillance of Anticoagulant Treatment, most of the 1700 patients followed-up are traditionally treated with acenocoumarol, while warfarin is administered nowadays to an increasing proportion of patients. To assess if the difference in the pharmacokinetics of these two drugs may determine a different laboratory quality of treatment, a retrospective study was performed on the computerized files of all 142 patients on treatment with warfarin for more than 100 days and on a control group of 142 patients treated with acenocoumarol, matched for age, sex, disease state and duration of oral anticoagulant therapy (OAT). The study considered 7071 assays for a total of 432 patient-years of treatment. The overall quality of treatment was significantly better in patients treated with warfarin (72% of controls within the therapeutic range versus 67% on acenocoumarol, p < 0.001). Also the individual quality of therapy, which was assessed as the percentage of patients with 75% or more assays in range, was in favour of warfarin (50.7% vs 34.5%, p < 0.05). Warfarin therapy was more stable and fewer assays were required for treatment monitoring. Confounding factors possibly influencing the treatment stability, such as interfering drugs, diagnostic or therapeutical procedures requiring withdrawal of anticoagulation, were evaluated and no significant difference between the two groups was found. The difference in the laboratory quality of OAT was marked in patients treated for prevention of arterial thromboembolism, while it was negligible in patients with venous thromboembolic disease, whose mean duration of OAT was considerably shorter. Since there is no evidence that acenocoumarol is more efficacious or safer than warfarin, the latter seems to be preferable for patients who are candidate to very prolonged OAT.

Acenocoumarol↗
PubMed1992

Variation in hemostatic parameters after intra-arterial and intravenous administration of iodinated contrast media.

RATIONALE AND OBJECTIVES: A few case reports have suggested a possible thrombogenic effect of nonionic contrast media. In vitro investigations have lead to conflicting results. The authors performed three ex vivo studies to evaluate the influence of an ionic, ioxaglate, and a nonionic, iopamidol, low-osmolality contrast medium on a series of clotting and fibrinolytic parameters, after intravenous or intra-arterial administration, during routine diagnostic procedures. METHODS: In the first study, iopamidol was given to 20 consecutive patients through an arterial catheter for digital subtraction arteriography (DSA). In the second study, iopamidol was compared with ioxaglate. The media were randomly and blindly administered intravenously to 21 consecutive patients undergoing brain computed tomography (CT). Finally, ioxaglate was administered intra-arterially to 20 consecutive patients, in a situation comparable with that of the first study. RESULTS: In the first study, a weak anticoagulant effect and an activation of fibrinolysis were found, associated with indirect markers of thrombin generation, such as increased plasma levels of fibrinopeptide A (FpA) and thrombin-antithrombin III complexes (TAT). In the second study, no significant changes were seen with either contrast medium, for thrombin or fibrinolysis activation parameters. In the third study, the intra-arterially administered contrast medium elicited a marked increase of FpA and TAT, together with an anticoagulant effect. CONCLUSION: Both ionic and nonionic contrast media are able to interfere with the clotting/fibrinolytic system in the general circulation when they are administered to patients at the usual dosages. Ioxaglate shows more marked anticoagulant and thrombin-generating effects than iopamidol. The procedure (ie, arterial catheter versus intravenous infusion) seems to be more important than the category of contrast medium in conditioning the magnitude of these effects.

Angiography, Digital Subtraction↗
PubMed1990

Subcutaneous vs intravenous heparin in the treatment of deep venous thrombosis--a randomized clinical trial.

271 patients with acute symptomatic deep venous thrombosis of lower limbs, confirmed by strain-gauge plethysmography and/or venography, were randomly assigned to receive intermittent subcutaneous heparin calcium or heparin sodium by continuous intravenous infusion for 6-10 days. Heparin dosage was adjusted to maintain activated partial thromboplastin time values (Thrombofax reagent) at 1.3-1.9 times the basal ones. Strain-gauge plethysmography was repeated at the end of heparin treatment, and evaluation of therapy was performed by comparing the indexes of venous hemodynamics and by assessing the incidence of pulmonary embolism and of bleeding complications. In the intravenous group, Maximal Venous Outflow (MVO) increased from 20.8 +/- 12.8 to 28.4 +/- 17.5 ml/min per 100 ml of tissue and Venous Capacitance (VC) from 1.39 +/- 0.92 to 1.94 +/- 1.0 ml/100 ml of tissue (mean +/- SD). In the subcutaneous group, MVO increased from 21.0 +/- 12.7 to 27.5 +/- 18.1 and VC from 1.60 +/- 0.86 to 2.06 +/- 1.0. The median improvement of MVO and VC were 22% and 36% respectively in the IV group and 20% and 24% in the SC group. Clinical pulmonary embolism occurred in 2 patients in the intravenous group (1 fatal) and in 4 in the subcutaneous group (1 fatal). 9 major bleeding complications occurred in the intravenous group (1 fatal) and 5 in the subcutaneous group (1 fatal). The differences were not significant at the statistical analysis. The results suggest that subcutaneous intermittent heparin has a comparable efficacy to continuous intravenous heparin in the treatment of deep venous thrombosis. To the same conclusion points an overview of the seven randomized trials which compared these treatment modalities.

Adolescent↗
PubMed1990

[Ultrasonography in the diagnosis of deep venous thrombosis of the legs].

One hundred consecutive inpatients with clinically suspected deep venous thrombosis (DVT) were examined by US; the last 19 cases were studied also by means of color-Doppler US. In order to evaluate the method reliability, US results were compared with those obtained with contrast venography, which was performed on all patients. The studied region included the femoro-popliteal vein, while no attempt was made to image the calf veins, which are difficult to evaluate with US. In our series, venographic results were in substantial agreement with US findings, with 99% and 100% sensitivity and specificity, respectively. Diagnosis was based only on noncompressibility of the thrombotic vein, despite the absence of visible clots; pulsed Doppler information supported diagnosis by evaluating blood flow. Further diagnostic progress was provided by color-Doppler US, which allows flow lumen to be defined in color. US also allowed the detection of the conditions mimicking DVT, such as muscular ruptures, hematomas, popliteal cysts, or compressive tumors. In conclusion, US and color-Doppler US prove to be valid alternatives to contrast venography in the diagnosis of proximal DVT of the lower limbs.

Adolescent↗
PubMed1989

Thromboembolic manifestations and congenital factor V deficiency: a family study.

A case of congenital factor V deficiency is reported. Despite this defect in blood coagulation, the patient had experienced recurrent thrombophlebitis and was referred to us because of deep venous thrombosis of the lower limbs associated with pulmonary embolism. Both functional and immunological assays documented a deficiency of factor V (12 and less than 10%, respectively). The available family members were investigated and the same defect was found in 2 brothers of the propositus, who also suffered from thrombotic diseases (recurrent thrombophlebitis and myocardial infarction). The propositus has been treated with long-term oral anticoagulant therapy, no hemorrhagic complications or thrombotic recurrences being recorded in 2 years' time.

Blood Coagulation Factors↗
PubMed1989

Acenocoumarol and pentoxifylline in intermittent claudication. A controlled clinical study. The APIC Study Group.

The efficacy and safety of pentoxifylline (400 mg tid orally) and acenocoumarol, administered singly or in combination, in the treatment of intermittent claudication associated with chronic occlusive arterial disease were evaluated in a multi-center, randomized, factorial, blind clinical trial involving 146 patients. The response to treatment was assessed by measuring pain-free walking time on the treadmill and by Doppler ankle/arm systolic pressure ratio at rest and after treadmill. Both pentoxifylline and acenocoumarol were significantly more effective than placebo in increasing the proportion of patients who improved their performance on the treadmill after one year of treatment. Benefit from active treatment was also apparent from the results of Doppler examinations performed after physical exercise. No significant differences were observed in comparing the effect of one active drug versus the other or versus the combined treatment. Five major hemorrhagic complications were registered in anticoagulated patients, two fatal cerebral hemorrhages and one gastrointestinal bleeding occurring in the group treated with both active drugs. The investigators conclude that (1) pentoxifylline is effective and safe in the treatment of patients with intermittent claudication (2) the benefits of oral anticoagulant therapy are outweighed by the risk of serious bleeding, and (3) the risk of bleeding is probably increased by the combined treatment with pentoxifylline.

Acenocoumarol↗
PubMed1983

[Arteriosclerosis obliterans of the lower limbs. Epidemiological study of the risk factors].

Chronic arterial occlusive disease of lower limbs is recognized as a typical multifactorial disease, but the role of some risk factors is still debated, because contrasting results have been obtained in epidemiological studies. We investigated the prevalence of hypercolesterolemia, hypertriglyceridemia, hypertension, smoking habits and diabetes in a population of 172 patients with peripheral arterial disease admitted to the III and V Medical Division of the "Ospedale Regionale" of Parma in the period January 1979 - April 1983, and in a control group of 174 subjects comparable for age and sex, free of clinical symptoms or signs of atherosclerosis. Statistically significant (p less than 0,005) increases in the prevalence of hypercolesterolemia, hypertriglyceridemia, smoking and hypertension were found in vascular patients compared with controls, the relative risk for the various considered factors being respectively: 6.40; 4.72; 4.03; 3.16.

Adult↗
PubMed1983

[Instrumental diagnosis of deep venous thrombosis. Prospective study with non-invasive methods].

The clinical diagnosis of deep vein thrombosis is unreliable and venography remains the best single method of investigation. In the last ten years several non-invasive procedures have been introduced in the vascular laboratories, sometime without adequate assessment of their reliability. We tested sensitivity and specificity of three different non-invasive procedures, namely phleboscintigraphy with 99Technetium, Doppler ultrasound technique and strain-gauge plethysmography in patients with clinically suspected deep vein thrombosis of lower limbs or pulmonary embolism. A total of 288 patients entered the study. Venography was used as the reference standard and was assessed independently, without knowledge of the results of non-invasive methods. In the first 36 patients phleboscintigraphy and Doppler ultrasound were evaluated: sensitivity and specificity of phleboscintigraphy resulted only a little more than 50%; the method was therefore considered unreliable and subsequently abandoned. Doppler ultrasound could be evaluated upon a total of 81 patients, showing an unsatisfactory sensitivity (63%), but a quite reliable specificity (86%). Best results were obtained with strain-gauge plethysmography, using maximal venous outflow and venous capacitance as diagnostic parameters. 209 patients entered this study, and a sensitivity of about 90% with a specificity of about 95% was observed. If we consider only acute proximal deep vein thrombosis, sensitivity approaches 97%, while it is only 60% in distal deep vein thrombosis.

Adolescent↗