ABSTRACT
Small platform guidewires with 0.014-in. diameters were developed to manage the smaller diameter arteries of the coronary vasculature. Coronary arteries range in size from less than 1 to 4 mm in diameter. Using higher caliber 0.035-in. diameter guidewires and 4-or 5-Fr catheters would be severely limiting in the coronary circulation. The routine use of 0.014-in. platforms in the coronary circulation has been standard for many years and more recently has been adapted for use in carotid, renal, and infrainguinal systems. The coronary system, in addition to being small diameter, is remote from major arterial access sites, such as femoral and upper extremity arteries. The monorail system or so-called “rapid exchange” system help to make long distance passage of devices faster and delivery more stable. Figure 1 demonstrates how a monorail system works.
