[Exercise test and nitrates].

Abstract

The use of sublingual nitroglycerin in the stress test is a precious tool in everyday clinical cardiology. It has several indications in this context: 1) Confirmation of the diagnosis of myocardial ischaemia by eliminating a large number of false-positives with no marked variation of ST depression and performance after sublingual nitroglycerin in contrast with patients presenting authentic myocardial ischaemia on effort. 2) Teaching of the preventive and opportunistic use of nitroglycerin before intense effort and before physical training which, in the long-term, is one of the most effective treatments of exertional angina pectoris. 3) Demonstration of potentiation of the effect of certain antianginal drugs such as beta-blockers. 4) In therapeutic trials, the stress test performed with sublingual nitroglycerin is used as a reference and to select patients capable of a fairly marked progression, so that they can be included in a protocol. It has the advantage of demonstrating a functionally measurable improvement of the stress test with an appropriate drug. 5) Progression with sublingual nitroglycerin during the stress test is related to regression of ischaemia i.e. restoration of functional viability of hibernating or shocked ischaemic segments of myocardium. It is probably the only realistic way to predict possible improvement after revascularization compared to other tests, which may be over-sensitive, as they detect zones with little capacity of regaining a viability which really contributes to cardiac output on exertion.