Nicotine patch therapy in smoking cessation reduces the extent of exercise-induced myocardial ischemia

Objectives. We sought to determine the effects of nicotine patch therapy, when used to promote smoking cessation, on myocardial ischemia in patients,vith coronary artery disease. Background. Nicotine patches substantially increase quit rates among cigarette smokers, but their safety in patients with myocardial ischemia who are attempting to quit smoking is unknown. Methods. This is a prospective study using exercise thallium-201 single-photon emission computed tomography (SPECT) to assess serial changes in the total and ischemic myocardial perfusion defect size at baseline while patients were smoking and during treatment with 14- and 21-mg nicotine patches. Entry criteria required that patients If smoked greater than or equal to 1 pack of cigarettes per day; 2) had known coronary artery disease; and 3) had myocardial ischemia (i.e., greater than or equal to 5% reversible perfusion defect) on SPECT. All patients performed symptom-limited treadmill exercise, and the baseline SPECT study served as its own control. We interpreted and computer quantified the SPECT images with no knowledge of the testing sequence. Results. Thirty-six of the 40 enrolled patients had exercise SPECT at baseline and during treatment with at least 14-mg nicotine patches. These patients had an initial perfusion defect size of 17.5 +/- 10.6% while smoking an average of 31 +/- 11 cigarettes per day for 40 +/- 12 years. A significant reduction in the total perfusion defect size (p < 0.001) was observed from baseline (17.5 +/- 10.6%) to treatment with 14-mg (12.6 +/- 10.1%) and 21-mg (11.8 +/- 9.9%) nicotine patches. This reduction occurred despite an increase in treadmill exercise duration (p < 0.05) and higher serum nicotine levels (p < 0.001). There was a significant correlation between the reduction in defect size and exhaled carbon monoxide levels (p < 0.001) because patients reduced their smoking by similar to 74% during the trial. Conclusions. Nicotine patches, when used to promote smoking cessation, significantly reduce the extent of exercise-induced myocardial ischemia as assessed by exercise thallium-201 SPECT. (C) 1997 by the American College of Cardiology.