Double-blind crossover comparison of the antianginal effects of nifedipine and isosorbide dinitrate in patients with exertional angina receiving propranolol

Safety and compatibility of betaxolol hydrochloride combined with diltiazem or nifedipine therapy in stable angina pectoris

Compared with placebo, adding betaxolol 20 mg every day to nifedipine (up to 60 mg/day in divided doses) or diltiazem (up to 360 mg/day in divided doses) for a 3-week treatment period in 135 patients with stable angina pectoris significantly (p < 0.05) lengthened the time to onset of moderate angina during exercise tolerance tests at all treatment time points. The median increases in the time to onset of moderate angina at the final exercise tolerance test (end point) compared with baseline were 1.08 and 0.53 minutes for betaxolol and placebo groups, respectively (p = 0.002, betaxolol and placebo groups, respectively (p = 0.002, betaxolol vs placebo). The time to onset of 1 mm ST-segment depression increased significantly (p < 0.05) with betaxolol compared with placebo at all but 1 treatment time point (median increase [p = 0.001] 1.77 and 0.37 minutes, respectively, at end point). Duration of exercise also was increased significantly (p < 0.05) after the third week of treatment and at end point (median 0.62 and 0.50 minutes, respectively; p = 0.03). Generally comparable results were found within the diltiazem (n = 128) and nifedipine (n = 25) subgroups, although the nifedipine group was too small to detect statistically significant differences between betaxolol and placebo treatment. Resting systolic blood pressure, heart rate and the rate-pressure product, measured both when angina occurred and at the end of exercise, also were influenced significantly (p < 0.05) by the betaxolol addition. The only serious adverse effect associated with betaxolol treatment was syncope, seen in 2 patients.

Nifedipine and isosorbide dinitrate alone and in combination for patients with chronic stable angina: a double-blind crossover study

Since not all patients tolerate beta-blockers, the efficacy of nifedipine and isosorbide dinitrate was evaluated alone and in combination in patients with stable angina pectoris. The study was a randomized double-blind crossover design with patients titrated to maximally tolerated doses of both drugs. Phases included isosorbide dinitrate alone, nifedipine alone, and isosorbide dinitrate plus nifedipine in combination, with efficacy determined by stress testing. Eleven men and one woman patient with a mean age of 60 years and a mean of five anginal episodes/week completed the study. Patients were in New York Heart Association (NYHA) classes I, II, and III. With nifedipine alone compared with isosorbide dinitrate alone, patients had fewer angina attacks/week (p less than 0.02), exercised longer before experiencing angina (p less than 0.03), and had less ST segment depression during (p less than 0.03) or after (p less than 0.05) exercise. When patients received isosorbide dinitrate plus nifedipine, only time to onset of angina during exercise (p less than 0.05) was significantly different from the response with isosorbide dinitrate alone. Analysis of variance between nifedipine and isosorbide dinitrate plus nifedipine was not significant. Diastolic blood pressure with isosorbide dinitrate plus nifedipine (p less than 0.04) was lower than with isosorbide dinitrate alone. No significant differences in systolic blood pressure were noted between the treatment groups. The drugs alone and in combination were relatively well tolerated. Nifedipine alone may be superior to isosorbide dinitrate alone. The combination of isosorbide dinitrate plus nifedipine demonstrated no advantage over nifedipine alone compared with isosorbide dinitrate alone.

Comparison of the anti-anginal efficacy of nicardipine and nifedipine in patients receiving atenolol: a randomized, double-blind, crossover study

The effects of oral nicardipine (40 mg) and nifedipine (20 mg) in combination with atenolol (100 mg) were compared with those of placebo, oral nitroglycerin (0.4 mg) and atenolol alone (100 mg) in 17 patients with stable effort angina. Patients performed symptom-limited, multistage, upright bicycle ergometric exercises with computer-assisted ECG analysis in bipolar lead CM5. Nicardipine and nifedipine were given double blind and in randomized order. In comparison with placebo (4818 +/- 2021 kpm), patients exercised longer and with a greater work load with nitroglycerin (5748 +/- 1711 kpm, P less than 0.001), the combinations of atenolol and nifedipine (6120 +/- 2274 kpm, P less than 0.05), and atenolol and nicardipine (6671 +/- 2339 kpm, P less than 0.01), but not with atenolol alone (5305 +/- 1524 kpm, P = NS). The magnitude of ST-segment depression at peak exercise with placebo (3.22 +/- 1.72 mm) was dramatically reduced with nitroglycerin (1.39 +/- 1.87 mm) but less with atenolol alone (2.95 +/- 1.83 mm, P less than 0.05) or the combinations of atenolol and nicardipine (3.05 +/- 1.51 mm, P = NS), and atenolol and nifedipine (2.45 +/- 1.25 mm, P less than 0.001). Compared to the combination of atenolol and nifedipine, that of atenolol and nicardipine produced a significantly (P less than 0.05) greater exercise tolerance (6671 +/- 2339 versus 6120 +/- 2274 kpm) but with a greater ST-segment depression at peak exercise (3.05 +/- 1.51 versus 2.45 +/- 1.29 mm, P less than 0.01).

Once-daily therapy for angina pectoris with nifedipine gastrointestinal therapeutic system. Dosing and clinical efficacy

The nifedipine gastrointestinal therapeutic system (GITS) is a promising new formulation that provides continuous release of nifedipine over the course of 24 hours with once-daily dosing. Results from a 14-week, open-label, crossover multicenter trial completed by 91 patients with chronic stable angina pectoris demonstrate that patients treated with standard nifedipine capsules may be switched to equivalent total 24-hour doses of nifedipine GITS and achieve comparable or improved efficacy (due to improved compliance) with a more favorable side-effects profile. Furthermore, in a subset of 10 patients who underwent sequential exercise testing, exercise responses obtained throughout 12 weeks of treatment with nifedipine GITS were comparable to measurements obtained during treatment with nifedipine capsules and demonstrated that tolerance did not occur. These patients also experienced significantly fewer vasodilatory side effects during treatment with nifedipine GITS compared with nifedipine capsules. Thus, nifedipine GITS represents a sound pharmacologic approach to the management of ischemic disease; and with once-daily dosing and a favorable side-effect profile this agent affords the potential for better patient compliance and efficacy without concern about the development of tolerance.

High-dose monotherapy and combination therapy with calcium channel blockers for angina. A comprehensive review of the literature

Clinical experience with the calcium channel-blocking agents has established their efficacy in the therapy of painful and silent myocardial ischemia. Questions have arisen, however, about side-effect characteristics of these medications as clinical practice has led to utilization of higher doses of individual drugs than employed in large numbers of patients in early clinical trials as well as combinations with other antianginal agents including beta-blockers. A study was undertaken to examine the published literature regarding side effects associated with high-dose versus low-dose therapy with nifedipine and diltiazem and the use of these agents in combination with beta-blockers. This investigation demonstrated that utilization of high-dose diltiazem (more than 240 mg per day) as opposed to low-dose diltiazem (no more than 240 mg per day) was associated with an increased incidence of atrioventricular block, and increased peripheral vasodilatory effects. In contrast, the use of high-dose nifedipine (more than 60 mg per day) was not associated with atrioventricular block. At clinically high dosage levels, the incidence of peripheral edema was comparable for both nifedipine and diltiazem, although low-dose nifedipine resulted in a significantly greater incidence of edema compared with low-dose diltiazem. This analysis also demonstrated that bradyarrhythmia is associated with the combination of a beta-blocking agent and either low- or high-dose diltiazem, but not with nifedipine-beta-blocker combinations. Clinical experience suggests caution in the combined use of diltiazem and a beta-blocking agent because of the demonstrated additional adverse negative chronotropic and dromotropic effects. No additional adverse electrophysiologic effects have been noted for nifedipine-beta-blocker combinations. The literature analysis supports and mirrors widespread clinical experience obtained since nifedipine and diltiazem were introduced. It should be noted, though, that combination therapy with calcium channel blockers and beta-blockers should be done with caution, since there have been occasional reports of congestive heart failure or exacerbation of angina with this combination.

Comparison of nifedipine and isosorbide dinitrate when added to maximal propranolol therapy in stable angina pectoris

A study was performed to compare isosorbide dinitrate and nifedipine as adjunctive therapy in 14 patients with coronary artery disease and stable angina pectoris taking maximal beta-blocking drugs. Drug titration phases ensured maximal therapy of propranolol, isosorbide or nifedipine. The combination of nifedipine and propranolol was more effective than the combination of isosorbide and propranolol in reducing angina and increasing exercise capacity (323 vs 416 seconds, p less than 0.005) during exercise treadmill testing. Nifedipine produced a greater reduction in systolic blood pressure at submaximal exercise than isosorbide. Global and regional ejection fraction at rest and exercise was assessed with radionuclide ventriculography. The substitution of nifedipine for isosorbide depressed the global ejection fraction at rest (0.61 to 0.56 p less than 0.05) and produced a slight improvement in exercise ejection fraction (0.47 to 0.51, difference not significant). The decrease in ejection fraction from rest to exercise was 0.14 to 0.04 with nifedipine (p less than 0.005). The benefit of nifedipine compared with isosorbide occurred in regions with marked exercise-induced ischemia. In patients treated with maximal beta-blocking therapy, nifedipine is an effective alternative to isosorbide as a combination agent with propranolol. The salutary effects of nifedipine included afterload reduction with exercise and possible improvements in coronary blood supply.

New therapeutic modalities for the treatment of elderly patients with ischemic heart disease

In developing a treatment plan for elderly patients with ischemic heart disease, it is important to appreciate that the pathophysiologic process and aging influence the type of response produced by various drugs. The aging process also alters the way drugs are absorbed, distributed, and eliminated. Each of these variables must be considered in deciding which drugs should be used and how they should be administered.

Silent myocardial ischemia: clinical characteristics, underlying mechanisms, and implications for treatment

A great deal of interest is being generated by the possibility that patients with coronary artery disease and typical angina pectoris may also experience periods of ischemia during activities of daily living that are not necessarily associated with angina or increased myocardial oxygen demand. It might be that the majority of ischemic episodes during daily life are not preceded by increases in myocardial oxygen demand, and are probably related to dynamic changes in coronary blood flow. Questions still remain, however, regarding the prevalence of asymptomatic ischemia in patients who present with effort angina and positive results on exercise tolerance tests. Therefore, in susceptible patients with coronary artery disease, calcium channel blockers, especially nifedipine, may be of particular benefit since they decrease myocardial oxygen demand during effort and may increase coronary blood flow, thereby aborting asymptomatic ischemia, which tends to occur at low levels of cardiac oxygen demand. It appears that a greater awareness of the total ischemic burden, i.e., the sum total of symptomatic and asymptomatic and exertional and nonexertional ischemia, may facilitate individualization of therapy for patients with coronary artery disease. Agents that both reduce myocardial oxygen demand and improve coronary blood flow, such as nifedipine, may particularly benefit individuals whose ischemia may be both asymptomatic and symptomatic, and who seem to constitute the majority of patients with coronary artery disease.