Potential MR Hazard to Patients With Metallic Heart Valves: The Lenz Effect

Comprehensive Analysis of Lenz Effect on the Artificial Heart Valves during Mag- Netic Resonance Imaging

This work presents results of a comprehensive analysis of the Lenz effect due to motion of artificial heart valves during magnetic resonance imaging. The interaction of rotating metallic heart valves with magnetic fields is studied by performing a time-domain analysis of the corresponding electromagnetic problem. We applied the finite element method (FEM) to solve the T − Ω formulation of Maxwe...

Pregnancy in patients with prosthetic heart valves.

Pregnancy and delivery were analyzed in 23 women one to ten years after undergoing prosthetic heart valve replacement. The main points of management during pregnancy and delivery were cardiac management and management against thromboembolism. The functional status of the pregnant patients was grade I of the New York Heart Association criteria in eight, grade II in 13 and grade III and higher in...

Anticoagulation in patients with mechanical heart valves: follow the guidelines!

year: the lowest in the youngest age group and the highest in the oldest. Intracranial haemorrhage was seen at an unacceptable rate (0.6–0.7/year) in all age groups. Therefore, the authors conclude that the use of mechanical AVR below the age of 60 years is associated with a similar rate of intracranial bleeding as seen in older patients. This report shows the deleterious effect of over-anticoa...

Safe MR scanning of patients with metallic middle ear implants

Black holes on MR images of the brain of patients with Björk-Shiley heart valves: additional observation in three cases.

We report the cases of three patients with Björk-Shiley convexo-concave heart valves with unusual black holes shown on cerebral MR images. For two patients, these findings were associated with fracture of the Björk-Shiley convexo-concave heart valve, and for the third, with worn surfaces on the heart valve. Susceptibility changes shown by MR imaging suggest the possibility that these black hole...