vitamin-k-1 and Atrial-Fibrillation

Vitamin K1 (VK1) reverses the effects of vitamin K antagonists (VKAs). The literature shows that the bioavailability from solutions might be higher than that from tablets, possibly resulting in different effects.. To compare the bioavailability and effect on the International Normalized Ratio (INR) of 5-mg VK1 tablets and solution in three randomized clinical trials.. The bioavailability was determined in a crossover trial with 25 healthy volunteers. VK1 plasma concentrations were assessed at 0, 2, 4, 5, 6, 8, 10 and 24 h, and the area under the curve was higher in the solution group than in the tablet group (mean difference 365 μg L(-1) h, 95% confidence interval [CI] 230-501, P < 0.0001). In the other two trials, the effects of both formulations on the INR were measured at 0, 24 and 48 h. In the second trial, on 72 patients on phenprocoumon with planned invasive procedures, both formulations were similarly effective, because all patients reached an INR of < 2.0, which was the primary endpoint. In the last trial, on 72 patients on phenprocoumon with an INR of 7.0-11.0, the INR decreased slightly more in the solution group (4.7, 95% CI 4.3-5.1) than in the tablet group (4.2, 95% CI 3.8-4.6). The solution group had a 3.3-fold increased likelihood (95% CI 0.7-15.1) of reaching an INR of < 2.0 at 48 h. Additionally, the increases in VK1 concentrations were similar (tablets, 3.2 μg L(-1) ; solution, 3.4 μg L(-1) ; P = 0.99) after 24 h.. VK1 tablets are at least as clinically effective as the solution in countering VKAs.

Topics: Administration, Oral; Adult; Aged; Antifibrinolytic Agents; Atrial Fibrillation; Biological Availability; Cross-Over Studies; Female; Healthy Volunteers; Humans; International Normalized Ratio; Likelihood Functions; Male; Middle Aged; Phenprocoumon; Tablets; Venous Thrombosis; Vitamin K 1

Topics: Administration, Oral; Anticoagulants; Atrial Fibrillation; Drug Administration Schedule; Heart Valve Prosthesis; Hemorrhage; Humans; Injections, Intravenous; International Normalized Ratio; Thromboembolism; Vitamin K 1; Warfarin

The most frequently used oral anti-coagulant warfarin has been implicated in inducing calcification of aortic valve interstitial cells (AVICs), whereas the mechanism is not fully understood. The low-level activation of p53 is found to be involved in osteogenic transdifferentiation and calcification of AVICs. Whether p53 participates in warfarin-induced AVIC calcification remains unknown. In this study, we investigated the role of low-level p53 overexpression in warfarin-induced porcine AVIC (pAVIC) calcification. Immunostaining, quantitative PCR, and Western blotting revealed that p53 was expressed in human and pAVICs and that p53 expression was slightly increased in calcific human aortic valves compared with non-calcific valves. Terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling staining indicated that apoptosis slightly increased in calcific aortic valves than in non-calcific valves. Warfarin treatment led to a low-level increase of p53 mRNA and protein in both pAVICs and mouse aortic valves. Low-level overexpression of p53 in pAVICs via an adenovirus vector did not affect pAVIC apoptosis but promoted warfarin-induced calcium deposition and expression of osteogenic markers. shRNA-mediated p53 knockdown attenuated the pAVIC calcium deposition and osteogenic marker expression. Moreover, ChIP and luciferase assays showed that p53 was recruited to the

Topics: Animals; Anticoagulants; Antifibrinolytic Agents; Aortic Valve; Atrial Fibrillation; Calcinosis; Cells, Cultured; Disease Models, Animal; Epigenesis, Genetic; Gene Expression Regulation; Genes, Reporter; Heart Valve Diseases; Humans; Male; Mice, Inbred C57BL; Promoter Regions, Genetic; Recombinant Proteins; Rheumatic Heart Disease; RNA Interference; Snail Family Transcription Factors; Sus scrofa; Tumor Suppressor Protein p53; Vitamin K 1; Warfarin

Anticoagulation of patients with cardiac tamponade (CT) complicating catheter ablation of atrial fibrillation (AF) is an ongoing problem. The aim of this study was to survey the clinical practice of periprocedural anticoagulation in such patients. This study analyzed the periprocedural anticoagulation of 17 patients with CT complicating AF ablation. Emergent pericardiocentesis was performed once CT was confirmed. The mean drained volume was 410.0 ± 194.1 mL. Protamine sulfate was administered to neutralize heparin (1 mg neutralizes 100 units heparin) in 11 patients with persistent pericardial bleeding and vitamin K1 (10 mg) was given to reverse warfarin in 3 patients with supratherapeutic INR (INR > 2.1). Drainage catheters were removed 12 hours after echocardiography confirmed absence of intrapericardial bleeding and anticoagulation therapy was restored 12 hours after removing the catheter. Fifteen patients took oral warfarin and 10 of them were given subcutaneous injection of LMWH (1 mg/kg, twice daily) as a bridge to resumption of systemic anticoagulation with warfarin. Two patients with a small amount of persistent pericardial effusion were given LMWH on days 5 and 13, and warfarin on days 6 and 24. The dosage of warfarin was adjusted to keep the INR within 2-3 in all patients. After 12 months of follow-up, all patients had no neurological events and no occurrence of delayed CT. The results showed that it was effective and safe to resume anticoagulation therapy 12 hours after removal of the drainage catheter. This may help to prevent thromboembolic events following catheter ablation of AF.

Topics: Aged; Anticoagulants; Antifibrinolytic Agents; Atrial Fibrillation; Blood Coagulation; Cardiac Tamponade; Catheter Ablation; China; Female; Hemorrhage; Heparin; Humans; Male; Middle Aged; Pericardial Effusion; Pericardiocentesis; Perioperative Period; Protamines; Retrospective Studies; Stroke; Vitamin K 1; Warfarin

Topics: Aged; Anticoagulants; Atrial Fibrillation; Factor VII Deficiency; Female; Humans; Vitamin K 1; Warfarin

Vitamin K is an essential factor for synthesis of plasma clotting proteins and for site-specific carboxylation of bone Gla protein and other bone matrix proteins. Low vitamin K has been associated with reduced bone mineral density. Warfarin therapy, which inhibits vitamin K-dependent blood-clotting, has been demonstrated to reduce the risk of stroke in nonrheumatic atrial fibrillation. We evaluated vitamin K and bone mineral density in nonrheumatic atrial fibrillation patients who had long-term warfarin therapy after an ischemic stroke.. Sera were collected from 64 patients with non-rheumatic atrial fibrillation and ischemic stroke who had been treated with warfarin, 63 stroke patients without warfarin, and 39 control subjects. All stroke patients in both groups had hemiplegia. Sera were assayed for vitamins K1 and K2, bone Gla protein, and 25-hydroxyvitamin D. Bone mineral density was determined in both second metacarpals.. Serum vitamin K1 concentrations (ng/mL) were lower in treated patients (.234 +/- .177 ng/mL) than in untreated patients (.329 +/- .284) or controls (.553 +/- .164). Bone Gla protein was lower in treated patients' sera (1.241 +/- .799 ng/mL) than in untreated patients (4.476 +/- 3.226). Concentrations of 25-hydroxyvitamin D were lower in both patient groups. Bone mineral density was lower on both sides in treated patients than in untreated patients (P < .0001). Vitamin K1 and bone Gla protein were significantly related to bone mineral density bilaterally in treated but not in untreated patients.. Bone mineral density was significantly lower in stroke patients with long-term warfarin treatment than in untreated patients. Both warfarin-induced reduction in vitamin K function and lowered vitamin K1 concentrations are probable causes of this osteopenia.

Topics: Administration, Oral; Aged; Anticoagulants; Antifibrinolytic Agents; Atrial Fibrillation; Bone Density; Cerebral Infarction; Female; Humans; Male; Middle Aged; Regression Analysis; Vitamin K; Vitamin K 1; Vitamin K 2

Topics: Anticoagulants; Aspirin; Atrial Fibrillation; Blood Transfusion; Coumarins; Digitalis Glycosides; Dose-Response Relationship, Drug; Duodenal Ulcer; Humans; Male; Middle Aged; Peptic Ulcer Hemorrhage; Rheumatic Heart Disease; Vitamin K 1