Comparison between Bruce and Ramp Protocols for Exercise Testing in the Diagnosis of Myocardial Ischemia

Abstract

The stress test consists in a procedure where an individual undergoes programmed physical exercise in order for the physician to assess clinical, hemodynamic, and electrocardiographic responses. 1 The exercise can be performed using a treadmill or a stationary cycle ergometer, and many protocols are available according to the test objective, being adaptable to patient conditions.Even though it was created more than 5 decades ago, the Bruce protocol is still the most widely used in the world's main laboratories. 2 Its increments are performed every 3 minutes, but an increase of around 3 metabolic equivalents of task (MET) at each stage may hinder the adaptation of sedentary individuals and those who have heart diseases and physical limitations, leading to the early interruption of the test.Technological advances allowed the creation of new protocols with smoother speed and incline increments, the so-called ramp tests. 3 The first report of the ramp protocol is from the 1980s using a stationary cycle ergometer and, in the following decade, with a treadmill. 4,5 The main advantage of the ramp protocol, with smoother and more linear increments when