title: Clinical efficacy and safety of once-daily diltiazem in patients with stable angina pectoris switched from twice-daily diltiazem.
abstract: The maintenance of angina control was assessed in this multicenter (three sites), randomized, double-blind, parallel-group study. Patients with stable angina pectoris receiving twice-daily sustained-release (SR) diltiazem were switched to equivalent doses of once-daily controlled-delivery (CD) diltiazem or to diltiazem SR. Patients who were switched from diltiazem SR to diltiazem CD (n = 28) experienced a 5% increase in time to termination (p = 0.0004) on the exercise tolerance test (ETT), as well as an 8% improvement in time to onset of angina (p < 0.0001) on the ETT. A similar trend was observed in patients randomized to diltiazem SR (n = 7), which suggested a training effect, and, therefore, equal efficacy between diltiazem SR and diltiazem CD. During exercise testing in the diltiazem SR baseline phase, 77% of the patients did not experience angina, whereas 60% of the patients did not experience ST-segment depression. Following transfer to diltiazem CD, 79 and 61% of patients, respectively, remained angina- and ST-segment depression free. No significant changes in the number of angina attacks, nitroglycerin use, or any hemodynamic-related parameters were observed following transfer to diltiazem CD. Eleven percent of the patients receiving diltiazem CD experienced treatment-related adverse events, which were limited to headache and abdominal pain; these adverse events did not lead to discontinuation of treatment. These findings suggest that patients whose angina is controlled with twice-daily diltiazem SR can be safely and effectively switched to an equivalent daily dose of the once-daily diltiazem CD.
authors.affiliation: Cardiology Department, Hopital Notre-Dame, Montreal, QC, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Savard
authors.forename: J
authors.initials: J
authors.lastname: Lenis
authors.forename: M
authors.initials: M
authors.lastname: Juneau
authors.forename: C
authors.initials: C
authors.lastname: Jacob
authors.forename: A P
authors.initials: AP
authors.lastname: Boulet
mesh_terms: D000368:Aged; D000787:Angina Pectoris / Q000188:drug therapy*; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D003692:Delayed-Action Preparations; D004110:Diltiazem / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005080:Exercise Test; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin / Q000008:administration & dosage; D014665:Vasodilator Agents / Q000008:administration & dosage
chemical_list: D002121:Calcium Channel Blockers; D003692:Delayed-Action Preparations; D014665:Vasodilator Agents; D004110:Diltiazem; D005996:Nitroglycerin