Thromboembolism frequency

Congenital deficiency of Factor XII is inherited as an autosomal recessive trait. Deficiency of this factor is rarely associated with any coagulopathy. It has been observed that people deficient in this factor may have an increased frequency of thromboembolic compHcations. 

Tamoxifen, clomiphene, and raloxifene are orally active. The primary route of excretion of all three drugs is in the feces. The undesirable effects common to all three of these SERMs are increased frequency of hot flashes and increased risk of thromboembolism. Both effects are attributable to their estrogenic activity. 

Raloxifene and clomiphene use is associated with an increased frequency of vasomotor disturbances (hot flashes) and thromboembolism formation. 

There are isolated reports of thromboembolic complications in recipients of desmopressin most occurred in patients with pre-existing vascular disease. However, in nine trials of the hemostatic efficacy of desmopressin in reducing blood and transfusion requirements in 763 patients, there were no significant differences between the frequencies of thromboembolism in subjects treated with desmopressin and controls (33). An analysis of 31 clinical trials of desmopressin in patients undergoing cardiac, vascular, orthopedic, or other major surgery showed that desmopressin did not increase the incidence of thrombosis (34). 

Home MK 3rd, Figg WD, Arlen P, Gulley J, Parker C, Lakhani N, Parnes H, Dahut WL. Increased frequency of venous thromboembolism with the combination of docetaxel and thalidomide in patients with metastatic androgen-independent prostate cancer. Pharmacotherapy 2003 23(3) 315-18. 

Several reviews of the adverse effects of vitamin E have been published (3,4), especially relating to premature infants (5), in whom high doses have been associated with infectious complications and fatal hepatic failure. In adults, thrombophlebitis, thromboembolism, pulmonary embolism, hypertension, fatigue, gynecomastia, and breast tumors have been described as particularly serious effects of vitamin E, but there is little evidence about their frequency. Diarrhea and abdominal pain can occur. For some of these effects there seems to be a dose relation. A dose of 800 mg/day for 30 days had no reported adverse effects in healthy elderly subjects (6). Table 1 shows reported adverse effects related to dosage in a review of about 50 publications on vitamin E (7). 

Adverse reactions include nausea, vomiting, and hot flashes. Vaginal bleeding, menstrual irregularities, and skin rash occur with less frequency. Hypercalcemia, edema, anorexia, depression, and thromboembolic events are uncommon but have been reported. 

Table 1 Frequency of hemorrhage and thromboembolism with routine medical care versus pharmacist-managed anticoagulation clinics...

Passive contraception No suppression of lactation No increased risk of thromboembolism May decrease seizure frequency... 

Our concern about peripheral thromboembolism led us to determine the occurrence of varicosities in a large sample of our volunteer subjects and in a group of controls. The data (Table XIII) indicate a reduced frequency of... 

Cardiac valves with components fabricated from low temperature isotropic carbons (pyrolytic carbon) are successfully used clinically [23]. These materials are appropriate for such applications as mechanical valves which require long-term chemical inertness, smoothness, and wear-resistance. The reasons for the marked improvement in the performance (reduced thrombosis and thromboembolic stroke rates) of these newer vs. older style heart valves are not entirely understood, but are undoubtedly multifactorial and related to improved patient management and valve design, as well as to the nature of the carbon surface. The specific benefits conferred by pyrolytic carbons with respect to blood cell and protein interactions, resulting in a very low frequency of clinical complications, remain to be defined. The use of carbon coatings has been proposed for other devices, i.e., vascular grafts, although such devices have not yet been used clinically. 

Clinical trials with dipyridamole for the reduction of thromboembolic complications after prosthetic cardiac valye replacement continue to show encouraging results.47 in a controlled study of 163 patients, dipyridamole (400 mg dally) significantly reduced the frequency of arterial emboli.56 On the other hand, dipyridamole was found to have no significant effect on postoperative deep vein thrombosis... 

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