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Representativeness of our Subjects Our subjects obviously were highly selected by the time they were entered into the definitive trial. Thus, one must ask whether our results can be extrapolated to the general population of patients with angina pectoris. The purpose of our study was not to evaluate the antianginal effectiveness of nitroglycerin patches for the large population of patients with chest pain thought to be anginal, or even for an unselected population of patients with unequivocal exercise-induced angina. It was rather to evaluate the potential effectiveness of the nitroglycerin patch per se as an antianginal agent, and as such required a be possible set of clinical circumstances. Namely, in a dition to being cooperative research subjects with stable, reproducible angina, the patients had to be e ccellent nitrate responders, free of nitrate-induced ide effects, and able to maintain at least some degree of nitrate responsiveness during long-term nitrate therapy. As such, our patients should be thought of as models for the best that can be achieved with nifhite-patch therapy, rather than representativ es for all patients with angina. Implications for Clinical Use We have demonstrated that nitroglycerin patches, w hen applied in adequate doses, can provide a significant day-long antianginal effect even in patients taking effective doses of nitrates long term. More importantly, however, our results point up the necessity for individual titration and for doses much greater than those generally employed. The need for titration and high doses may well render this mode of therapy too difficult to institute, as well as too cumbersome and expensive for most patients to continue. The overwhelming majority of patients who w'ear a single 10- or 20-sq cm patch continuously for 24 hours are probably gaining no pharmacologic therapeutic benefit.