Exercise Body Surface Potential Mapping in Single and Multiple Coronary Artery Disease: Methods (Part 3)
The protocol was reviewed and approved by the Research Review Committee of the Victoria General Hospital and all patients and normal subjects gave informed consent prior to participation. buy ortho tri-cyclen online
In all CAD patients an intravenous access route was established in a large peripheral vein prior to the usual application of BSPM electrodes, for subsequent thallium infusion. All subjects exercised while supine, on a bicycle ergometer, beginning with 25 W resistance and incrementing at 25 W every 3 min. Exercise endpoint in the CAD patients was either worsening visceral chest pain (angina), 0.1 mV ST depression in lead V5, or leg fatigue (Table 2). The normal control subjects exercised to preselected target heart rates, matched to the CAD patients’ peak rates flable 3). Supine exercise was utilized in an ‘effort to minimize torso motion artifact and because of some evidence that false-positive ST segment changes normalize more rapidly in the supine position.
In the patients with CAD, thallium was injected intravenously during the last minute of exercise and, following termination of exercise, all subjects were kept in the supine position for a further 5-min recovery period. The BSPM electrodes then were removed and all patients underwent initial thallium perfusion scanning.