The Ventrica Magnetic Vascular Positioner system is a novel automatic anastomotic coupling device for distal coronary artery anastomosis. There is concern that enormous magnetic fields may negatively affect graft anastomosis or coronary artery blood flow, or that they may lead to disconnection of the magnetic ports. Forty-five domestic swine (26.6 +/- 5.9 kg) underwent magnetic resonance imaging after a single Ventrica anastomosis of the left internal mammary artery to the left anterior descending artery. Group A (n = 15) underwent magnetic resonance imaging immediately after surgery, group B (n = 15) was studied after 1 week, and group C (n = 15) after 2 weeks. The animals were sacrificed and the anastomotic sites were examined. All animals survived the imaging procedure. Mean imaging time was 25 +/- 6 min. Although imaging artifacts occurred in the area surrounding the Ventrica port, there were no disconnections or electrocardiographic signs of ischemia during the study period. Upon sacrifice, all anastomoses were patent without alterations in the alignment of the magnetic components. Clinically relevant tests such as cranial magnetic resonance imaging may be safe after use of the Ventrica system for coronary artery revascularization.