Early graft thrombosis due to antithrombin III deficiency following CABG

The serine protease inhibitor antithrombin III (AT-III), an ??2-globulin synthesized in the liver and endothelial cells, is the principal in vivo inhibitor of blood coagulation inactivating mainly thrombin. AT-III deficiency presents a rare hereditary or acquired disorder that most often comes to light when a patient suffers recurrent venous thrombosis and pulmonary embolism. Triggers for the onset of the thrombosis include various mechanisms such as pregnancy, delivery, surgery, trauma, and contraceptive pill use. Decreased response to heparin may be the first sign of AT-III deficiency. Since heparin is a conditio sine qua non for cardiopulmonary bypass, rapid consumption of AT-III promoted by heparin may lead to systemic thrombosis. The effect of heparin on graft patency after CABG in patients with AT-III deficiency, particularly with respect to early graft thrombosis, has not been fully investigated. The early detection and timely treatment of this disorder may impact perioperative morbidity. We present a case of simultaneous thrombosis of three venous grafts after elective coronary artery bypass surgery in a patient with AT-III deficiency.     

Familial deficiency of antithrombin III

The systematic search for a deficiency in antithrombin III must be considered in case of: venous thrombosis in a young patient, recurrent venous thrombosis especially if these occurred under Heparin, venous mesenteric infarction since this type of thrombosis is rare and seems relatively frequent in case of congenital deficiency in antithrombin III, familial past history of venous thrombosis in a woman desiring to undergo estrogen-progesterone therapy. The most often used techniques are: study of antithrombin III activity by amidolytic method and titration by immunodiffusion. Anti-vitamin K treatment is the only effective therapy proposed to patients suffering from a hereditary deficiency in antithrombin III.     

Cerebral thrombosis in a newborn with a congenital deficiency of antithrombin III

An Israeli Arab family with type I antithrombin III (AT-III) deficiency with several affected symptomatic members in three generations is reported. The propositus presented with deep vein thrombosis and pulmonary emboli associated with gestation. The propositus infant presented at the age of 2 weeks with superior sagittal and rectus sinus thrombosis. Hereditary AT-III deficiency should be considered in infants with cerebral thrombosis, especially if they have a family history of thromboembolism. The role of prophylactic therapy by AT-III concentrates in these infants should be further assessed.     

Management with antithrombin III concentrate in a pregnant woman with hereditary antithrombin III deficiency

Pregnant women with hereditary antithrombin III (AT-III) deficiency are frequently associated with thromboembolic disorders. We have treated a pregnant woman with hereditary AT-III deficiency, who had suffered from thromboembolic disorders at her past three gestations, with AT-III concentrate. Dosage of AT-III concentrate to maintain plasma AT-III activity over 80% was 3,500 units per week during second and third trimesters, but more frequent administration was necessary around delivery. In recent reports, pregnant women with hereditary AT-III deficiency had been treated with heparin or warfarin except for during abortion and delivery, in which time AT-III concentrate was widely utilized. But the use of heparin or warfarin during gestation is occasionally harmful, AT-III concentrate should be chosen for management in pregnancy in women with hereditary AT-III deficiency.     

Acute aortic thrombosis and antithrombin III deficiency in the nephrotic syndrome: a case report

A 25-year-old Oriental woman with nephrotic syndrome was admitted to the United States Naval Hospital in Okinawa. She had acute aortic thrombosis, which was managed initially with bilateral femoral thrombectomy and calf fasciotomies. In the early postoperative period, increasing doses of heparin were required to maintain adequate anticoagulation. Hematologic evaluation revealed a deficiency of antithrombin III (AT-III). Such a deficiency has been recognized as occurring in nephrotic syndrome, most probably due to urinary loss of this serum protein. Five prior cases of acute aortic thrombosis have been described in the nephrotic syndrome, but only three reports of acute aortic thrombosis have been attributed to documented AT-III deficiency. Acute thrombosis due to AT-III deficiency may be confirmed by measuring decreased serum levels of this protein. Treatment is initiated with fresh frozen plasma and heparin, with subsequent utilization of oral warfarin.     

Effective prophylaxis of thrombosis by antithrombin III concentrate in a pregnant woman with congenital antithrombin III deficiency: relations between plasma antithrombin III activity and the plasma levels of hemostatic molecular markers.

The value of antithrombin III (AT III) concentrate and a standard criterion for its use were examined in a pregnant woman with congenital AT III deficiency by continuous monitoring of plasma AT III activity and the plasma levels of hemostatic molecular markers. The rates of improvement of various markers after AT III administration (frequency of improvement/frequency of administration) were as follows: fibrinopeptide A (FPA) 82%, D-dimer 70%, fibrinopeptide B beta 15-42 73%, beta-thromboglobulin 60%, and platelet factor 4 50%. There was no significant correlation between the plasma AT III activity and all plasma FPA values, but FPA values of over 3.9 ng/ml showed a significant negative correlation with AT III activity: AT III activity (%) = -6.59 x FPA (ng/ml) + 125, r = -0.851, p less than 0.02. We therefore recommend continuous monitoring of the plasma FPA level and administration of AT III concentrate when the FPA level is elevated. According to the regression line shown above, plasma AT III activity should be raised to 100% to keep the FPA level below 6.0 ng/ml with 95% confidence limit.     

Hereditary antithrombin III deficiency: Effect of antithrombin III deficiency on platelet function

Antithrombin III (AT III) is the main physiologic inhibitor of thrombin, and activated factors X and IX as well. Normal levels of AT III appear to be necessary to maintain blood fluidity and to prevent thrombosis. Four families with AT III deficiency and recurrent venous thromboembolism have been reported on. We present an additional family with AT III deficiency and a high incidence of thromboembolism. AT III levels were determined by both a functional and an immunologic assay. Results of platelet function tests, not previously reported in persons with AT III deficiency, were found to be normal. Following gel filtration, the platelets were very sensitive to thrombin. Thrombin-induced platelet aggregation appears to be dependent on a balance between the amount of thrombin and AT III present.     

Pulmonary arterial thrombosis in a neonate with homozygous deficiency of antithrombin III: successful outcome following pulmonary thrombectomy and infusions of antithrombin III concentrate

We report a newborn male who presented with severe central cyanosis on the third day of life. Partial thrombotic obstruction of the pulmonary trunk secondary to Antithrombin III (homozygous defect of heparin binding site) deficiency was subsequently diagnosed. Surgical thrombectomy, and infusions of Antithrombin III concentrate, led to a successful outcome. We postulate that intrauterine thrombosis occurred to give this unusual presentation.     

Acquired antithrombin III deficiency]

Acquired antithrombin III (AT III) deficiency is based on either decreased activity or synthesis, increased loss or increased consumption. The activity of AT III is decreased in metabolic acidosis, hyperlipoproteinemias and by lipid peroxides. Chronic liver diseases especially liver cirrhosis are associated with very low levels of AT III due to insufficient hepatic synthesis, reduced transcapillary flux ratios, diffuse intravascular coagulation and loss in the ascites. Gastrointestinal loss of AT III may occur in patients with active inflammatory bowel diseases. AT III deficiency is observed in nephrotic syndrome when urinary loss of protein exceeds 5 g/d. During hemodialysis we have not found low AT III levels. Disseminated intravascular coagulation is characterized by activation of the coagulation system and increased consumption of AT III. AT III complexes with activated coagulation factors are subsequently cleared by the reticuloendothelial system.     

Danazol and antithrombin III deficiency

The study concerned 7 subjects (3 men, 4 women) with nonfamilial antithrombin III deficit which, in the absence of known causes of acquired deficiency, was defined as "sporadic". Danazol (an attenuated synthetic androgen) already shown to be capable of compensating for a lack of certain antiproteases, was given in doses of 200 mg 3 times per day for 10 days, resulting in a rapid rise (mean 21.2%) in antithrombin III values. Unlike results reported in the literature in cases of familial antithrombin III deficit, the levels did not drop below their initial values despite discontinuance of the drug but unexpectedly remained high and even shows a slight subsequent rise. Although our study was limited to 11 cases, these data seem worthy of being reported, with the prospect of other confirmations concerning either this sort of "sporadic" antithrombin III deficit or the favorable effect of Danazol, even at long term.     

Prophylactic use of antithrombin III concentrate following surgery in congenital antithrombin III deficiency

Antithrombin III is the major physiological inhibitor of thrombin, and congenital deficiency of antithrombin III is associated with increased risk of venous thrombosis either spontaneously or following trauma, surgery or pregnancy. The successful use of antithrombin III concentrate during and following surgery to prevent venous thrombosis is described in a previously asymptomatic man with familial antithrombin III deficiency.     

Treatment of venous thrombosis in antithrombin III deficient patients with concentrates of antithrombin III

Summary Two patients with familial antithrombin III deficiency developed deep venous thrombosis of the lower limb. The diagnosis of venous thrombosis was made by the indium labelled platelet technique which also allowed for the daily assessment of thrombus size. Each patient received treatment with Warfarin, subcutaneous heparin, and infusions of antithrombin III concentrates. The authors conclude that infusions of antithrombin III concentrates may be of value in limiting the extent of acute thrombosis in patients with a severe deficiency of this protein and may help prevent pulmonary embolism. The haemorrhagic risk of continuing modest doses of heparin with high dose ATIII therapy appears small. In addition to its value in the diagnosis of venous thrombosis the indium platelet technique may give an early indication of thrombus extension and may thus indicate the effectiveness of treatment.