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1.
J Ultrasound ; 13(4): 158-63, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23397004

RESUMEN

INTRODUCTION: Liver metastases often exhibit a hypervascular halo during the arterial phase of contrast-enhanced ultrasonography (CEUS). This finding has no correlates on baseline gray-scale imaging, and it has never been characterized. The aim of this study was to identify the features of this halo and determine whether it should be included in the ablation volume during thermal ablation procedures. MATERIALS AND METHODS: We prospectively enrolled 25 patients referred to our department for thermal ablation of liver metastases. Before treatment all patients underwent CEUS, and the maximum diameter of the metastatic lesion was measured before administration of the ultrasound contrast agent and during the arterial and portal venous phases of the contrast contrast-enhanced study. Maximum diameters in the different vascular phases were compared with the Turkey-Kramer test. Two biopsies were obtained from each lesion with a 21-gauge needle: 1) one from the center of the metastasis to confirm the diagnosis and 2) one from the hypervascular peripheral halo identified in the arterial phase at CEUS. RESULTS: The mean (±standard deviation) maximum lesion diameter was 2.67 ± 1.2 cm before contrast agent injection, 3.50 ± 1.4 cm during the arterial phase, and 2.71 ± 1.2 cm during the venous phase. The difference between maximum diameters measured before contrast enhancement and in the arterial phase was highly significant (mean: 0.84 ± 0.45 cm, p < 0.0001). Histological examination of halo specimens revealed inflammatory infiltrates with no evidence of tumor infiltration in 24/25 (96%) cases and normal hepatic parenchymal tissue in the 25th specimen. DISCUSSION: The hypervascular halo surrounding liver metastases during the arterial phase of CEUS represents a chronic inflammatory infiltrate, not tumor infiltration. However, since chronic inflammation appears to promote neovascularization and the production of tumoral growth factors, it seems wise to include the hypervascular halo in the intended-to-treat volume when planning the ablation procedure.

2.
Clin Genet ; 73(2): 171-8, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18177470

RESUMEN

The aim of this study was to search for SLC40A1 mutations in iron overloaded patients, which tested negative for HFE mutations and other iron-related genes. After a careful differential diagnosis, we selected 56 patients with unexplained iron overload whose phenotype could suggest the ferroportin disease. Iron overload was assessed by liver biopsy or by superconducting quantum interference device. SLC40A1 exons and intron-exon boundaries were amplified by polymerase chain reaction and sequenced. We also evaluated the presence of the insulin-resistance hepatic iron overload and of non-alcoholic fatty liver disease. Iron status was assessed in 44 families. We identified two novel mutations (D157N and V72F) at the heterozygous state in two probands. Phenotype heterogeneity was observed in both families, suggesting variable penetrance and expression. Including the two affected ones, 25 of the 44 families (57%) available for the iron study had one or more relatives with increased serum iron indices. Our findings not only suggest that the presence of major alterations of serum iron parameters in probands' relatives is a main criteria to improve the power of the genetic testing for ferroportin disease but also indicate that a number of patients exists in which the etiology of iron overload remains still undefined.


Asunto(s)
Proteínas de Transporte de Catión/genética , Sobrecarga de Hierro/genética , Adulto , Anciano , Sustitución de Aminoácidos , Femenino , Ferritinas/sangre , Humanos , Hierro/sangre , Masculino , Persona de Mediana Edad , Linaje , Penetrancia , Transferrina/metabolismo
3.
Dig Liver Dis ; 35(7): 479-81, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12870733

RESUMEN

BACKGROUND: In the Italian general population, prevalence of C282Y is lower than in Northern European countries. We hypothesised a higher prevalence of C282Y in Northern than in Central and Southern Italy. We previously identified a nonsense mutation (W169X) in haemochromatosis probands originating from a Northern Italian region (Brianza). AIM: To define the prevalence of HFE mutations in that region. Subjects and methods. A total of 1132 unrelated blood donors from the Blood Banks of Monza and Merate were investigated for C282Y, H63D, S65C and W169X mutations by PCR-restriction assays. A total of 300 were also tested for rare HFE and TFR2 mutations by reverse-hybridization test strips. RESULTS: Two C282Y homozygotes, eight C282Y/H63D compound heterozygotes, 27 H63D homozygotes and one W169X heterozygote were found. The allele frequencies of C282Y, H63D, S65C, and W169X were 3.2, 13.4, 1.3, and 0.04%, respectively. CONCLUSIONS: Our results confirm the existence of a decreasing frequency of C282Y allele from upper to lower Northern Italy. This difference is probably related to the larger Celtic component of upper Northern Italian populations in which screening studies for haemochromatosis may even be cost effective. W169X, due to its severity, should be looked for in all haemochromatosis patients of Northern ancestry with an incomplete HFE genotype.


Asunto(s)
Etnicidad/genética , Frecuencia de los Genes , Genética de Población , Antígenos de Histocompatibilidad Clase I/genética , Proteínas de la Membrana/genética , Mutación , Adulto , Anciano , Genotipo , Proteína de la Hemocromatosis , Humanos , Italia/epidemiología , Persona de Mediana Edad , Prevalencia
4.
Thromb Haemost ; 86(4): 991-4, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11686357

RESUMEN

Recent clinical trials have demonstrated a better ability of low-molecular-weight heparin, compared to unfractionated heparin, in reducing ischemic cardiac events in patients with acute coronary syndromes without ST-segment elevation. No data are available concerning the in-vivo comparison of enoxaparin and unfractionated heparin on thrombin generation in patients with unstable angina or non-Q-wave myocardial infarction. We measured the plasma levels of prothrombin fragment 1+2 (a marker of prothrombin activation) and thrombin/antithrombin complex (a marker of thrombin generation) in 45 patients with non ST-elevation acute coronary syndromes who were randomized to receive enoxaparin, 3000 IU anti-Xa as an i. v. bolus, followed by 70 IU anti-Xa/Kg every 8 h for 3 days (23 pts. Group 1) or a bolus of 100 IU/kg of unfractionated heparin followed by infusion for 3 days titrated to maintain the aPTT between 70 and 90 s (22 pts, Group 2). Plasma levels of prothrombin fragment 1+2 reduced significantly at 3rd h of treatment in both groups (-42% in Group 1 and -45% in Group 2), reached the lowest plasma concentration at the 24th h and exhibited a slight increase at the 72nd h; no differences were observed between the two groups at any time points. Plasma thrombin/antithrombin complex levels had a similar behaviour: reduced markedly in both groups at the 3rd h (-52% in Group 1 and -46% in Group 2), remained lower during the first two days and slightly rose at 72nd h. No differences between the two groups in plasma levels of this marker were apparent during drug infusion. In Group 1 the aPTT did not show significant changes: in Group 2 the mean value of aPTT doubled the basal value at any time point of determination. Both enoxaparin and unfractionated heparin produced a marked and similar reduction of thrombin generation. Other unknown mechanisms might explain the different clinical effects of the two heparins.


Asunto(s)
Angina Inestable/tratamiento farmacológico , Anticoagulantes/uso terapéutico , Trombosis Coronaria/tratamiento farmacológico , Enoxaparina/uso terapéutico , Heparina/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Trombina/biosíntesis , Enfermedad Aguda , Anciano , Angina Inestable/sangre , Anticoagulantes/farmacología , Antitrombina III/análisis , Biomarcadores , Fármacos Cardiovasculares/uso terapéutico , Comorbilidad , Trombosis Coronaria/sangre , Trombosis Coronaria/fisiopatología , Quimioterapia Combinada , Electrocardiografía , Enoxaparina/farmacología , Femenino , Heparina/farmacología , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Infarto del Miocardio/fisiopatología , Tiempo de Tromboplastina Parcial , Fragmentos de Péptidos/análisis , Péptido Hidrolasas/análisis , Protrombina/análisis , Factores de Riesgo , Resultado del Tratamiento
6.
Cardiologia ; 43(8): 825-32, 1998 Aug.
Artículo en Italiano | MEDLINE | ID: mdl-9808873

RESUMEN

Myocardial infarction and thrombolysis are proven to be associated with platelet activation. However, the time relationship of platelet activation with the onset of symptoms and with thrombolysis, and the response to aspirin are not well defined. In this study we measured platelet activity in the early phase of myocardial infarction treated with either streptokinase or recombinant tissue-type plasminogen activator (rt-PA) and evaluated whether and to what extent it may be counteracted by aspirin. Fourty-one patients (mean age 57 +/- 6 years) received thrombolytic therapy after coronary occlusion: 1.5 million units of streptokinase (Group 1; 21 patients) or 100 mg of rt-PA (Group 2; 20 patients). Ten randomly selected patients in either group were given 500 mg aspirin i.v. prior to infusion of the thrombolytic compound and, then, 325 mg/die of aspirin orally. Beta-thromboglobulin (BTG), a marker of platelet activity, was determined at admission, after thrombolysis and in the subsequent 48 hours. At admission, BTG plasma levels averaged 125 +/- 31 IU/ml in Group 1 and 134 +/- 35 IU/ml in Group 2 (NS). Thrombolysis produced a similar increase in platelet activity in both groups, and maximal values were reached at the third hour (196 +/- 43 IU/ml in Group 1 and 192 +/- 39 in Group 2, p < 0.001 vs baseline and NS between groups). Levels of BTG were higher in streptokinase-treated group starting from 24 hours (p < 0.05). Differences in BTG levels between aspirin-treated and aspirin-untreated patients became significant at 48 hours after thrombolysis in both groups. An inverse correlation was found between time elapsed from onset of symptoms and BTG value on admission (r = -0.86, p < 0.001); in patients admitted within 2 hours after the beginning of symptoms, and having the higher BTG levels, thrombolysis did not induce a significant increase in platelet activity; this, on the contrary, was observed in patients admitted later. Platelet activation is greater early after myocardial infarction and is differently influenced by thrombolytic treatment, depending on the delay of the patient's admission. Streptokinase and rt-PA induce a similar increase in platelet activity which is more persistent after streptokinase; cycloxygenase inhibition with aspirin seems to influence platelet activity only starting from the second day.


Asunto(s)
Plaquetas/fisiología , Infarto del Miocardio/tratamiento farmacológico , Terapia Trombolítica , beta-Tromboglobulina/análisis , Adulto , Anciano , Aspirina/farmacología , Aspirina/uso terapéutico , Plaquetas/efectos de los fármacos , Interpretación Estadística de Datos , Femenino , Fibrinolíticos/farmacología , Fibrinolíticos/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Activadores Plasminogénicos/farmacología , Activadores Plasminogénicos/uso terapéutico , Estreptoquinasa/farmacología , Estreptoquinasa/uso terapéutico , Factores de Tiempo , Activador de Tejido Plasminógeno/farmacología , Activador de Tejido Plasminógeno/uso terapéutico
7.
Am Heart J ; 135(3): 503-9, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9506337

RESUMEN

BACKGROUND: Mechanisms of restenosis after percutaneous transluminal coronary angioplasty (PTCA) have not been defined yet. Experimental studies have shown that thrombin, by stimulating platelet growth factor secretion and smooth muscle cell proliferation, can play a major role. METHODS AND RESULTS: In 34 patients with single-vessel coronary disease undergoing PTCA, thrombin activity was evaluated through serial fibrinopeptide A (FPA) plasma determinations. Samples were performed before PTCA, immediately after and 24 hours, 72 hours, and 6 months later. Patients were grouped according to the development (group 1, n = 13) or nondevelopment (group 2, n = 21 ) of restenosis at a 6-month angiographic control. No difference in the two groups was found concerning baseline FPA values. In patients in group 1, soon after PTCA higher FPA levels (27.3 +/- 13.7 ng/ml) than those in group 2 (9.2 +/- 5.6 ng/ml; p < 0.05 vs pre-PTCA, and p < 0.01 between the two groups) were observed. No differences in FPA levels were detected at the other steps between the two groups. CONCLUSION: Our data suggest that thrombin plays a role in the process of restenosis after PTCA; acute FPA response to the procedure seems to have a predictive value.


Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad Coronaria/fisiopatología , Enfermedad Coronaria/terapia , Trombina/fisiología , Anciano , Angina Inestable/fisiopatología , Angina Inestable/terapia , Angiografía Coronaria , Femenino , Fibrinopéptido A/análisis , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/fisiopatología , Isquemia Miocárdica/terapia , Recurrencia , Factores de Tiempo
8.
J Thromb Thrombolysis ; 5(1): 65-71, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-10608053

RESUMEN

Background. Platelet activation after myocardial infarction and thrombolytic treatment has been documented; but its relationship with the onset of symptoms and with thrombolysis, and the influence of aspirin in this setting is not well defined. In this study we measured platelet activity in the early phase of myocardial infarction treated with either streptokinase or rt-PA and evaluated influence of aspirin in this framework.Methods. 41 patients (age 57 +/- 6 years) were treated with thtombolytic therapy during myocardial infarction; 21 patients with 1,5 million units of streptokinase (Group 1) and 20 patients with 100 mg of rt-PA (Group 2); 10 randomly selected patients in each group were given 500 mg aspirin i.v. prior to infusion of thrombolytic drug and, subsequently, 325 mg aspirin a day orally. Consecutive samples of beta-thromboglobulin (BTG), a marker of platelet activity, were collected at admission and after thrombolysis for the following 48 hours. Results. At admission, BTG plasma levels averaged 125 +/- 31 IU/ml in Group I and 134 +/- 35 IU/ml in Group 2 (p = 0.81). Thrombolysis was followed by a similar increase of platelet activity with maximal values reached at the 3rd hour in both groups (196 +/- 43 IU/ml in Group 1 and 192 +/- 39 in Group 2: p < 001versus baseline and p NS between the groups). Higher levels of BTG were observed in streptakinase-treated group starting from the 24th hour (p < 0.05). Patients treated with aspirin showed lower levels of BTG only from the 48th hour after thrombolysis in both groups. An inverse correlation was found between time elapsed from onset of symptoms to admission and BTG value on admission (r = -0.86 p < 0,001); in patients admitted within two hours from the beginning of symptoms, with higher levels of BTG, thrombolysis not induced a significant increase of platelet activity; who was observed in patients admitted later.Conclusions. A marked platelet activation is more evident in the first hours of myocardial infarction and is differently influenced by thrombolytic treatment in relation with the delay of patient presentation. Both streptokinase and rt-PA induce a similar increase of platelet activity which is more persistent after streptokinase; cyclooxygenase inhibition seems to influence the platelet activity only from the second day.Condensed abstract. Influence of aspirin on platelet activity during myocardial infarction treated with thrombolytic therapy is not well defined. Twenty-one patients treated with streptokinase (Group 1) and 20 patients treated with rt-PA (Group 2) were randomly selected to give 500 mg of aspirin i.v. prior thrombolysis and subsequently 325 mg a day orally. Platelet activity was evaluated through determination of beta-thromboglobulin plasma levels. Thrombolysis was followed by a similar increase of platelet activity in both groups with maximal values reached at the 3rd hour; higher levels of beta-thromboglobulin were observed in streptokinase-treated group starting from 24th hour. Treatment with aspirin reduced beta-thromboglobulin plasma levels only at 48th hour in both groups.

9.
Cardiologia ; 42(12): 1277-83, 1997 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-9534323

RESUMEN

Renin-angiotensin system promotes sodium and chloride retention, participates in the defense response to hypovolemia and, in congestive heart failure, contributes to edema formation and progression of the disease. We investigated whether ACE-inhibitors interfere with the action of the renin-angiotensin system on the nephron, and therefore with water and urinary electrolytes excretion. The interaction among renin-angiotensin system, diuretic treatment and urinary electrolytes was evaluated both during chronic treatment and in response to acute renin-angiotensin system activation as that observed after extracorporeal ultrafiltration-induced transient hypovolemia. Plasma renin activity and aldosterone, body fluid balance and urinary sodium, chloride and potassium concentrations were evaluated in 30 patients with congestive heart failure in NYHA II-III functional class, grouped according to whether long-term therapy did not include (Group I, n = 15) or included (Group II, n = 18) ACE-inhibitors. All parameters were evaluated at baseline and after a single session of extracorporeal ultrafiltration. At baseline, urinary output and urinary sodium and chloride concentrations were similar in the two groups, while urinary potassium concentration was lower in patients assuming ACE-inhibitors (Group II). Plasma renin activity was higher and aldosterone was lower in Group II than in Group I. After removal of similar amounts of plasma water by extracorporeal ultrafiltration, body weight decreased in both groups but the decrease was maintained in the following days only in Group II patients. A transient reduction (48 hours) of both plasma volume and urinary output was observed after ultrafiltration in both groups. Despite plasma renin activity and aldosterone increase, urinary electrolytes response to ultrafiltration was different in the two groups: sodium and chloride were reduced, and potassium did not change in Group 1 while, in Group II, sodium and chloride did not change and potassium excretion was significantly increased. In conclusion, chronic treatment with ACE-inhibitors does not enhance the excretion of sodium in congestive heart failure but just mitigates potassium loss. The role of these drugs becomes particularly relevant during acute renin-angiotensin system activation due to hypovolemia; in this setting ACE-inhibitors counteract sodium and chloride retention resulting in a potential hazard due to interference with the defence mechanisms toward hypovolemia, and an amplification of extracorporeal ultrafiltration efficacy by preventing edema recovery after its mechanical removal.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Electrólitos/orina , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/fisiopatología , Anciano , Volumen Sanguíneo/fisiología , Femenino , Insuficiencia Cardíaca/orina , Humanos , Masculino , Persona de Mediana Edad
10.
Eur Heart J ; 17(2): 230-6, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8732376

RESUMEN

Procoagulant activity, thrombin and fibrinolytic system activation have been demonstrated in the first 24-48 h after acute myocardial infarction treated with thrombolytic therapy. Little is known about what happens in the subsequent days, during which the incidence of ischaemic recurrence is high. In 21 patients treated with streptokinase and in 20 patients treated with urokinase we evaluated, with multiple plasma determinations, D-dimer and fibrinogen plasma levels in the first week after myocardial infarction. From the 2nd hour after the beginning of thrombolysis to the 4th day, all patients received intravenous heparin in doses sufficient to raise the partial thromboplastin time to twice its normal level; subcutaneous calcium heparin (12,000 U/day) was subsequently substituted for the intravenous route. Coronary angiography was performed 7 days after infarction. From the basal values 2.22 +/- 1.44 nmol.1(-1) in the streptokinase group and 3.28 +/- 3.05 nmol.1(-1) in the urokinase group, D-dimer rose consistently in the 1st hour after thrombolysis 269.4 +/- 206.7 nmol.1(-1) and 44.5 +/- 35.5 nmol.1(-1) in the streptokinase and urokinase groups, respectively; P < 0.001. After the peak value, which in both groups was reached after 5 h, D-dimer slowly decreased during the study period. It reverted to normal values only in 10/21 patients in the streptokinase group; in the urokinase group normalization was attained in 14/20 patients between the 3rd and 6th days. After withdrawal of i.v. heparin in patients of both groups with TIMI 0 or 1 grade of coronary patency, D-dimer rose to levels four to seven times greater than normal; in patients of both groups with TIMI 2 or 3 grade coronary flow, D-dimer showed a monophasic pattern of progressive normalization (P < 0.05 and P < 0.01 at the 6th and 7th days, respectively, for differences between TIMI 0-1 and TIMI 2-3 groups). After myocardial infarction, thrombolysis is followed by active and persistent fibrin degradation more marked and lasting after streptokinase than after urokinase. When occurring sooner, it is a consequence of plasmin activation induced by thrombolytic agents; later it seems to be related to intracoronary substrate, as suggested by the relationship of plasma elevation of D-dimer with the presence of occluded or suboccluded infarction-related vessels.


Asunto(s)
Fibrinólisis/fisiología , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/fisiopatología , Terapia Trombolítica , Anciano , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Fibrinógeno/análisis , Fibrinolíticos/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Activadores Plasminogénicos/uso terapéutico , Estreptoquinasa/uso terapéutico , Factores de Tiempo , Activador de Plasminógeno de Tipo Uroquinasa/uso terapéutico
11.
Cardiologia ; 40(1): 15-22, 1995 Jan.
Artículo en Italiano | MEDLINE | ID: mdl-8529234

RESUMEN

Hypovolemia stimulates the sympathoadrenal and renin systems and water retention. In congestive heart failure (CHF) reduced cardiac output and blood pressure have been suggested to be perceived as a volume deficit, which, if persistent, would perpetuate humoral activation and fluid retention. In the aim of probing this hypothesis, we monitored in patients with CHF the neurohumoral response to reduction of the body fluid obtained by ultrafiltration. In 22 patients with advanced CHF and fluid retention, ultrafiltration was performed with a diafilter, which was part of an external venous circuit, whose flow was regulated to produce 500 ml/hour of ultrafiltrate (average total amount 3,122 +/- 1,199 ml) until right atrial pressure was reduced to 50% of baseline. Hemodynamics, plasma renin activity, norepinephrine and aldosterone were measured before and in the 48 hours after ultrafiltration. Soon after the procedure, associated with a 20% reduction of plasma volume and a moderate decrease of cardiac output and blood pressure (consistent with a diminished degree of filling of the arterial compartment), there was an obvious fall of norepinephrine, plasma renin activity and aldosterone. In the next 48 hours we recorded an increasing neurohumoral axis depression, in spite of recovery of plasma volume, cardiac output and blood pressure and a striking enhancement in urinary output. Changes in norepinephrine, plasma renin activity or aldosterone were not related to the combination of changes in plasma volume, cardiac output and blood pressure (variations in the state of arterial filling) and significantly correlated with the increase in urinary output and sodium excretion.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Diuresis , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/terapia , Norepinefrina/fisiología , Volumen Plasmático , Adulto , Aldosterona/sangre , Presión Sanguínea , Gasto Cardíaco Bajo , Retroalimentación/fisiología , Femenino , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico , Norepinefrina/sangre , Renina/sangre , Factores de Tiempo , Ultrafiltración
12.
Circulation ; 90(6): 2666-70, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7994806

RESUMEN

BACKGROUND: We have previously shown that treatment with streptokinase induces abrupt complement activation and transient neutropenia in patients with acute myocardial infarction (AMI). The purpose of this study was to compare the effects of two different thrombolytic agents--streptokinase (SK) and recombinant tissue-type plasminogen activator (rTPA)--on activation of the complement and kinin systems in plasma of patients with AMI. METHODS AND RESULTS: Forty-one patients with AMI who were eligible for thrombolytic therapy were studied. Twenty-three patients were treated with streptokinase (1.5 million IU IV over 60 minutes) and 18 were treated with rTPA (8 with bolus of 10 mg IV, followed by 50 mg infused over 60 minutes and then 40 mg infused over 120 minutes; 10 patients were administered rTPA and heparin according to the accelerated infusion protocol indicated by the GUSTO study). C4a and C3a were measured by radioimmunoassay, soluble terminal complement components (SC5b-9) and anti-SK IgG antibodies were measured by ELISA. Cleaved high molecular weight kininogen (HK) was quantitated in plasma by SDS-PAGE and immunoblotting analysis. C4a levels were significantly and similarly increased in both groups, whereas the levels of C3a and SC5b-9 after rTPA infusion were only slightly elevated and were significantly lower than after SK. No differences were observed between patients treated with slow or accelerated rTPA regimens. The titer of antibodies to SK was highly correlated with the levels of C3a and SC5b-9, whereas a lesser correlation was observed with C4a. Treatment with rTPA did not induce the transient neutropenia observed after SK infusion. The cleavage products of HK were significantly greater after SK than after rTPA infusion. CONCLUSIONS: Our results show that both thrombolytic agents activate the classic complement pathway and that plasmin could be the common trigger for this phenomenon. A significant activation of the complement common pathway (from C3 to terminal components) was observed only with SK infusion and is attributable to the rapid formation of immunocomplexes between SK and anti-SK antibodies present in plasma as a consequence of previous streptococcal infections. The minimal activation of C5 component of the common pathway explains the absence of leukopenia in patients treated with rTPA. Cleavage of HK, larger after SK than after rTPA infusion, represents a condition enhancing the generation of bradykinin by kallikrein. The recent experimental data that indicate a damaging effect of complement activation on the infarcted zone and the contrasting favorable effect consequent to bradykinin formation raise some questions about the clinical importance of the different biological consequences of SK versus rTPA.


Asunto(s)
Activación de Complemento , Cininas/fisiología , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/terapia , Estreptoquinasa/uso terapéutico , Terapia Trombolítica , Activador de Tejido Plasminógeno/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Activación de Complemento/efectos de los fármacos , Complemento C3a/análisis , Complemento C4a/análisis , Complejo de Ataque a Membrana del Sistema Complemento , Proteínas del Sistema Complemento/análisis , Femenino , Glicoproteínas/análisis , Humanos , Quininógenos/química , Quininógenos/fisiología , Recuento de Leucocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes
13.
Br Heart J ; 72(6): 534-9, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7857735

RESUMEN

BACKGROUND: Hypovolaemia stimulates the sympathoadrenal and renin systems and water retention. It has been proposed that in congestive heart failure reduction of cardiac output and any associated decrease in blood pressure cause underfilling of the arterial compartment, which promotes and perpetuates neurohumoral activation and the retention of fluid. This study examined whether an intravascular volume deficit accounts for patterns that largely exceed the limits of a homoeostatic response, which are sometimes seen in advanced congestive heart failure. METHODS AND RESULTS: In 22 patients with congestive heart failure and water retention the body fluid mass was reduced by ultrafiltration and the neurohumoral reaction was monitored. A Diafilter, which was part of an external venous circuit was regulated to produce 500 ml/hour of ultrafiltrate (mean (SD) 3122 (1199) ml) until right atrial pressure was reduced to 50% of baseline. Haemodynamic variables, plasma renin activity, noradrenaline, and aldosterone were measured before and within 48 hours of ultrafiltration. After ultrafiltration, which produced a 20% reduction of plasma volume and a moderate decrease in cardiac output and blood pressure (consistent with a diminished degree of filling of the arterial compartment), there was an obvious decrease in noradrenaline, plasma renin activity, and aldosterone. In the next 48 hours plasma volume, cardiac output, and blood pressure recovered; the neurohumoral axis was depressed; and there was a striking enhancement of water and sodium excretion with resolution of the peripheral oedema and organ congestion. The neurohumoral changes and haemodynamic changes were not related. There were significant correlations between the neurohumoral changes and increase in urinary output and sodium excretion. CONCLUSIONS: In advanced congestive heart failure arterial underfilling was not the main mechanism for activating the neurohumoral axis and retaining fluid. Because a decrease in circulating hormones was associated with reabsorption of extravascular fluid it is likely that hypoperfusion and/or congestion of organs, such as the kidney and lung, reduce the clearance of circulating noradrenaline and help to keep plasma concentrations of renin and aldosterone raised. A positive feedback loop between fluid retention and plasma hormone concentrations may be responsible for progression of congestive heart failure.


Asunto(s)
Líquidos Corporales/metabolismo , Insuficiencia Cardíaca/metabolismo , Hemofiltración , Neurotransmisores/metabolismo , Anciano , Aldosterona/sangre , Agua Corporal/metabolismo , Retroalimentación , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/fisiopatología , Hematócrito , Humanos , Riñón/metabolismo , Masculino , Persona de Mediana Edad , Norepinefrina/sangre , Volumen Plasmático , Renina/sangre , Sodio/metabolismo , Volumen Sistólico
14.
Am Heart J ; 128(3): 472-6, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8074007

RESUMEN

In vitro and in vivo studies have shown both an inhibition and an activation of platelets after thrombolysis in acute myocardial infarction. Plasma beta-thromboglobulin, a marker of platelet activity, was evaluated daily during the first week after myocardial infarction in 24 patients who received intravenous streptokinase (group 1) and 26 who did not (group 2). On admission, levels of beta-thromboglobulin, as compared to those in healthy subjects (35 +/- 9 IU/ml), were similarly augmented in group 1 (105 +/- 27 IU/ml) and in group 2 (115 +/- 30 IU/ml); 3 hours later, values averaged 191 +/- 58 IU/ml in group 1 (p < 0.001 vs baseline) and 95 +/- 28 IU/ml in group 2 (not significant vs baseline; p < 0.001 between the two groups). From the second to the seventh day, beta-thromboglobulin augmented in those patients in both groups with postinfarction angina. From day 5 to day 7, patients of group 1 without angina had lower beta-thromboglobulin levels than patients of group 2 who had no symptoms. The lowest levels of platelet activity were observed in group 1 reperfused patients. These data indicate that in myocardial infarction an early platelet activation takes place that is enhanced by thrombolytic treatment; recurrence of angina is associated with persistent activation; in the absence of recurrent angina, thrombolysis can limit late platelet activation.


Asunto(s)
Infarto del Miocardio/sangre , Infarto del Miocardio/tratamiento farmacológico , Estreptoquinasa/administración & dosificación , Terapia Trombolítica , beta-Tromboglobulina/análisis , Angina de Pecho/sangre , Femenino , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Activación Plaquetaria , Recurrencia
15.
Eur Heart J ; 15(5): 654-9, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8056006

RESUMEN

The purpose of this study was to investigate whether, to what extent, and through which mechanisms intravenous heparin, administered before and after streptokinase, affects the plasma levels of D-dimer and fibrinogen in myocardial infarction. Data concerning mortality and incidence of coronary recanalization in patients receiving heparin and thrombolytic therapy after acute myocardial infarction are controversial; furthermore, the mechanisms through which heparin acts in combination with thrombolytic therapy are unclear. Thirty-eight patients with acute myocardial infarction treated with streptokinase were considered. Nineteen of them received, immediately before the beginning of thrombolytic treatment, a bolus of heparin (100 U.kg-1 intravenously) and, 2 h later, intravenous heparin in doses raising the partial thromboplastin time to 2-2.5 times the normal value (Group 1); the remaining 19 did not receive anticoagulant treatment (Group 2). Multiple determinations of plasma D-dimer and fibrinogen levels were obtained in all patients before, and in the seven days following thrombolytic treatment. Six hours after streptokinase, fibrinogen decreased from 304 +/- 34 to 61 +/- 34 mg.dl-1 in Group 1 and from 312 +/- 29 to 38 +/- 21 mg.dl-1 in Group 2 (P < 0.02 versus Group 1). The same difference between groups persisted at the 12th and at the 18th hour. D-dimer values, from 0.5 +/- 0.1 microgram.dl-1 in Group 1 and 0.4 +/- 0.1 microgram.dl-1 in Group 2, increased at the 1st hour to 37.2 +/- 36.5 micrograms.dl-1 and 52.2 +/- 39.8 micrograms.dl-1, respectively. A peak value was reached in both groups at the 6th hour, which was followed by a slow decrease.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Fibrinógeno/metabolismo , Heparina/farmacología , Infarto del Miocardio/tratamiento farmacológico , Estreptoquinasa/uso terapéutico , Terapia Trombolítica , Ensayo de Inmunoadsorción Enzimática , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/efectos de los fármacos , Fibrinógeno/efectos de los fármacos , Heparina/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Factores de Tiempo
16.
Cardiologia ; 39(4): 253-9, 1994 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-8062296

RESUMEN

Extracorporeal ultrafiltration (UF) can improve the clinical condition, as assessed by cardiopulmonary exercise evaluation, of patients with moderate heart failure (HF); the pre-UF level of physical performance above which UF does not induce clinical benefits, is not defined. For this purpose, we studied 29 patients with stable HF in functional class II-III (NYHA), who underwent UF (veno-venous bypass, removal of 1,830 +/- 550 ml of plasma water), regardless their baseline oxygen consumption at peak exercise (VO2p) and at anaerobic threshold (VO2AT). All patients experienced cardiopulmonary exercise tests (cycloergometer, increasing workloads of 25 W every 3 min) before (pre-UF), and 4 days and 3 months following UF. According to VO2 changes following UF 2 groups of patients were identified: in Group I (9 patients) no differences in VO2p and VO2AT were observed, while in Group II (18 patients) VO2p rose by 2.7 ml/min/kg (p < 0.001) at 4 days and 4.5 ml/min/kg (p = 0.04) at 3 months, and VO2AT rose by 1.2 ml/min/kg (p < 0.001) at 4 days and 2.8 ml/min/kg (p = 0.03) at 3 months. In unresponsive patients baseline values of VO2p > or = 18 ml/min/kg and VO2AT +/- 13 ml/min/kg were detected. Pre-UF VO2p inversely correlated with the shift of VO2p (delta VO2p) both at 4 days (r = -0.62, p < 0.001) and at 3 months (r = -0.53, p = 0.005), and pre-UF VO2AT inversely correlated with delta VO2AT at 4 days (r = -0.71, p < 0.001) and at 3 months (r = -0.63, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Ejercicio Físico , Insuficiencia Cardíaca/terapia , Hemofiltración , Consumo de Oxígeno , Anciano , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
17.
Cardiologia ; 38(7): 425-9, 1993 Jul.
Artículo en Italiano | MEDLINE | ID: mdl-8221736

RESUMEN

Ultrafiltration improves the clinical condition of patients with moderate congestive heart failure. Ultrafiltration (1895 +/- 120 ml of plasma water, rate 600 ml/h, veno-venous bypass) was performed in 30 patients with moderate congestive heart failure in stable clinical conditions. The effects of ultrafiltration were assessed through pulmonary function and cardiopulmonary exercise tests performed before and 30 days after the procedure. Vital capacity, forced expiratory volume (1 s) and maximal voluntary ventilation improved as improved exercise performance (increase in oxygen consumption at peak exercise and at anaerobic threshold). Tidal volume at anaerobic threshold and at peak exercise increased by 10% with no changes in respiratory rate. This suggests that ultrafiltration induces changes at the physical characteristics of the lungs probably related to changes in lung water content.


Asunto(s)
Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/terapia , Hemofiltración , Pulmón/fisiopatología , Anciano , Fenómenos Biofísicos , Biofisica , Prueba de Esfuerzo , Volumen Espiratorio Forzado , Humanos , Ventilación Voluntaria Máxima , Persona de Mediana Edad , Capacidad Vital
18.
Cardiologia ; 38(5): 287-95, 1993 May.
Artículo en Italiano | MEDLINE | ID: mdl-8104696

RESUMEN

We investigated the mechanisms involved in the regulation of salt and water metabolism in patients with congestive heart failure (CHF). Extracorporeal ultrafiltration was utilized as a nonpharmacologic method for withdrawal of body fluids. In 32 consecutive patients with CHF (NYHA class II to IV) and different degrees of water retention, 24-hour diuresis and natriuresis were inversely best correlated with the combination of circulating renin, aldosterone, norepinephrine, and renal perfusion pressure (RPP). Fluid removal (600 to 5,000 ml) at a rate of 500 ml/h, until right atrial pressure decreased to 50% of baseline, caused variable humoral, circulatory, and diuretic effects that were mainly related to the extent of fluid retention. In fact, in 10 patients (Group 1) with overhydration refractory to drug therapy and with urinary output less than 1,000 ml/24 h (mean 370 ml), soon after the procedure, plasma renin (-39%), aldosterone (-50%), and norepinephrine (-47%) were reduced and RPP was increased (+ 16%), and in the subsequent 24 hours, diuresis was increased by 493%; in 9 patients (Group 2) whose baseline urinary output exceeded 1,000 ml/24 h (mean 1,785 ml), renin increased by 40%, norepinephrine, aldosterone and RPP each decreased by 12%, and diuresis remained unchanged; in 13 patients (Group 3) with a daily urinary excretion as in Group 2 and without overhydration, RPP decreased (-7%), renin (+ 196%), aldosterone (+ 170%), and norepinephrine (+ 52%) increased, and diuresis decreased by 45%. There was an overall correlation (p < 0.0001) between the combination of changes in these circulatory and hormonal variables and changes in diuresis and natriuresis with ultrafiltration.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Insuficiencia Cardíaca/metabolismo , Equilibrio Hidroelectrolítico , Adulto , Anciano , Diuresis , Femenino , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/terapia , Hemodinámica , Hemofiltración , Humanos , Masculino , Persona de Mediana Edad , Natriuresis , Neurotransmisores/sangre
19.
J Am Coll Cardiol ; 21(2): 424-31, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8426008

RESUMEN

OBJECTIVES: The aim of this study was to evaluate whether ultrafiltration is beneficial in patients with moderate congestive heart failure. BACKGROUND: Ultrafiltration is beneficial in patients with severe congestive heart failure. METHODS: We studied 36 patients in New York Heart Association functional classes II and III in stable clinical condition. Eighteen patients (group A) were randomly selected and underwent a single session of ultrafiltration (venovenous bypass, mean [+/- SEM] ultrafiltrate 1,880 +/- 174 ml, approximately 600 ml/h) and 18 (group B) served as control subjects. RESULTS: Two patients in group A and three in group B did not complete the 6-month follow-up study. In group A, soon after ultrafiltration there were significant reductions in right atrial pressure (from 8 +/- 1 to 3.4 +/- 0.7 mm Hg, pulmonary wedge pressure (from 18 +/- 2.5 to 10 +/- 1.9 mm Hg) and cardiac index (from 2.8 +/- 0.2 to 2.3 +/- 0.2 liters/min). During the follow-up period, lung function improved, extravascular lung water (X-ray score) decreased and peak oxygen consumption (ml/min per kg) increased significantly from 15.5 +/- 1 (day -1) to 17.6 +/- 0.9 (day 4), to 17.8 +/- 0.9 (day 30), to 18.9 +/- 1 (day 90) and to 19.1 +/- 1 (day 180). Oxygen consumption at anaerobic threshold (ml/min per kg) also increased significantly from 11.6 +/- 0.8 (day -1) to 13 +/- 0.7 (day 4), to 13.7 +/- 0.5 (day 30), to 15.5 +/- 0.8 (day 90) and to 15.2 +/- 0.8 (day 180). These changes were associated with increased ventilation, tidal volume and dead space/tidal volume ratio at peak exercise. The improvement in exercise performance was associated with a decrease in norepinephrine at rest, a downward shift of norepinephrine kinetics at submaximal exercise and an increase in norepinephrine during orthostatic tilt. None of these changes were recorded in group B. CONCLUSIONS: In patients with moderate congestive heart failure, ultrafiltration reduces the severity of the syndrome.


Asunto(s)
Insuficiencia Cardíaca/terapia , Hemodinámica/fisiología , Hemofiltración , Anciano , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/diagnóstico , Pruebas de Función Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Norepinefrina/sangre , Pruebas de Función Respiratoria , Factores de Tiempo , Ultrafiltración
20.
Am J Med ; 94(1): 49-56, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8420299

RESUMEN

PURPOSE: We investigated the mechanisms involved in the regulation of salt and water metabolism in patients with congestive heart failure (CHF). Extracorporeal ultrafiltration was utilized as a nonpharmacologic method for withdrawal of body fluid. PATIENTS, METHODS, AND RESULTS: In 32 consecutive patients with CHF (New York Heart Association functional class II to IV) and different degrees of water retention, 24-hour diuresis and natriuresis were inversely best correlated with the combination of circulating renin, aldosterone, norepinephrine, and renal perfusion pressure (RPP, mean aortic pressure minus mean right atrial pressure). Fluid withdrawal (600 to 5,000 mL) at a rate of 500 mL/h, until right atrial pressure decreased to 50% of baseline, caused variable humoral, circulatory, and diuretic effects that were mainly related to the extent of fluid retention. In fact, in 10 patients (Group 1) with overhydration refractory to drug therapy and with urinary output less than 1,000 mL/24 h (mean, 370 mL), soon after the procedure, plasma renin (-39%), aldosterone (-50%), and norepinephrine (-47%) were reduced and RPP was increased (+16%), and in the subsequent 24 hours, diuresis was increased by 493%; in 9 patients (Group 2) whose baseline urinary output exceeded 1,000 mL/24 h (mean, 1,785 mL), renin increased by 40%, norepinephrine, aldosterone, and RPP each decreased by 12%, and diuresis remained unchanged; in 13 patients (Group 3) with a daily urinary excretion as in Group 2 and without overhydration, RPP decreased (-7%), renin (+196%), aldosterone (+170%), and norepinephrine (+52%) increased, and diuresis decreased by 45%. There was an overall correlation (p < 0.0001) between the combination of changes in these circulatory and hormonal variables and changes in diuresis and natriuresis with ultrafiltration. CONCLUSIONS: It appears that in CHF, (1) retention of sodium and water results from an interaction of hormonal and hemodynamic (primarily RPP) alterations that may exert a reciprocal positive feedback; (2) depending on the presence and severity of fluid retention, the response to withdrawal of body fluid may vary from neurohumoral activation and restriction of diuresis to neurohumoral depression and extreme potentiation of salt and water excretion; (3) refractory CHF requires the interruption of the humoral-hemodynamic vicious circle, and ultrafiltration is able to accomplish that.


Asunto(s)
Insuficiencia Cardíaca/fisiopatología , Hemodinámica/fisiología , Norepinefrina/metabolismo , Cloruro de Sodio/metabolismo , Ultrafiltración , Agua/metabolismo , Adulto , Anciano , Aldosterona/metabolismo , Diuresis , Femenino , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/terapia , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Renina/metabolismo , Ultrafiltración/métodos
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