Nicotine patch appears safe in smokers with CAD

Nicotine patches used for smoking cessation are safe in patients with coronary artery disease (CAD) and active stress-induced myocardial ischemia, said Monika J. Leja, MD, pictured left, at the 2007 American College of Cardiology annual scientific session.

She and colleagues at The Methodist DeBakey Heart Center in Houston studied 55 heavy smokers with > 9% perfusion defect size on single photon emission computed tomography (SPECT), randomizing them to a nicotine patch (21 mg) or a placebo patch while they continued to smoke.

The safety of nicotine patches in patients with CAD who continue to smoke is uncertain because nicotine is known to increase heart rate and blood pressure, and may induce vasoconstriction, said Dr. Leja, a cardiology fellow. Nicotine patches are known to approximately double the quit rate, compared with quitting "cold turkey."

The subjects smoked a mean of 29 cigarettes per day at baseline. SPECT scans were repeated after 1 week, and then the subjects were encouraged to stop smoking and continue patch use. Another SPECT scan was performed at week 4. Ischemia on SPECT imaging has been shown to increase the risk of subsequent coronary events in patients with CAD.

Levels of nicotine and exhaled carbon monoxide (CO) were measured prior to each SPECT and were compared between the group randomized to the active patch and those randomized to the placebo patch.

Compared with baseline, nicotine patch users had a greater reduction of CO level at week 1 (22.3 vs. 15.1 parts per million [ppm]) than the placebo patch users (23 vs. 21.7 ppm). This finding was consistent with a fewer number of cigarettes smoked in the active patch wearers (11.5 vs. 17.2 per day at week 1).

As expected, nicotine levels increased significantly in the nicotine patch wearers but despite this increase, there was no significant change in the total or ischemic perfusion defect size from baseline in the active patch wearers, compared with the placebo patch wearers.

The total perfusion defect size did not change significantly in either group from baseline to week 1. The total perfusion defect size went from 24.8% at baseline to 24.2% at week 1 in those assigned the nicotine patch, and from 21.1% at baseline to 18.6% at week 1 in the subjects assigned the placebo patch.

"There were trends that showed that perfusion defect size did not change at week 4 either," said Dr. Leja, which suggest continued safety of the nicotine patch in CAD patients.