Safety of Nitrate Withdrawal in Angina-Free and Hemodynamically Stable Patients With Coronary Artery Disease

Abstract

To assess the consequences of nitrate withdrawal in angina-free and hemodynamically stable coronary patients. Prospective, open, intervention study. Cardiology outpatient clinic of a university-affiliated municipal hospital. Angina-free patients who were hemodynamically stable for at least 3 months before study onset were enrolled. They were all regularly receiving nitrates for symptom control. Those with significant reasons to avoid stopping nitrates, such as heart failure (ejection fraction <35%) or high BP (> 160 mm Hg systolic and/or > 100 mm Hg diastolic), and noncompliant patients were excluded. After providing informed consent and undergoing an exercise test (whenever possible), the participants were randomized to abruptly discontinue (study group) or continue (control group) nitrate treatment. Follow-up continued for at least 3 months after study entry. Eighty patients were randomized to the study group and 40 patients to the control group (mean age [+/- 1 SD], 65.5 +/- 11 years and 66.1 +/- 10.9 years, respectively; p = not significant). The first month, eight study patients (10%) had a recurrence of anginal symptoms, compared with one control subject (2.5%) [p = not significant]. All eight patients responded promptly and favorably to the resumption of nitrate administration. Nitrate administration can be safely discontinued in angina-free and hemodynamically stable coronary patients who receive this medication on a regular basis. If relapse of anginal symptoms occurs, it will be within 1 month following nitrate withdrawal, and will resolve satisfactorily with reinstatement of treatment.