Diltiazem versus propranolol in essential hypertension: responses of rest and exercise blood pressure and effects on exercise capacity

Effects of propranolol and exercise training in children with severe burns

OBJECTIVES

To investigate whether propranolol administration blocks the benefits induced by exercise training in severely burned children.

STUDY DESIGN

Children aged 7-18 years (n = 58) with burns covering ≥30% of the total body surface area were enrolled in this randomized trial during their acute hospital admission. Twenty-seven patients were randomized to receive propranolol, whereas 31 served as untreated controls. Both groups participated in 12 weeks of in-hospital resistance and aerobic exercise training. Muscle strength, lean body mass, and peak oxygen consumption (VO2 peak) were measured before and after exercise training. Paired and unpaired Student t tests were used for within and between group comparisons, and χ(2) tests for nominal data.

RESULTS

Age, length of hospitalization, and total body surface area burned were similar between groups. In both groups, muscle strength, lean body mass, and VO2 peak were significantly greater after exercise training than at baseline. The percent change in VO2 peak was significantly greater in the propranolol group than in the control group (P < .05).

CONCLUSIONS

Exercise-induced enhancements in muscle mass, strength, and VO2 peak are not impaired by propranolol. Moreover, propranolol improves the aerobic response to exercise in massively burned children.

Hypertension update and cardiovascular risk reduction in physically active individuals and athletes

Hypertension is a prevalent disease worldwide. Its inadequate treatment leads to major cardiovascular complications, such as myocardial infarction, stroke, and heart failure. These conditions decrease life expectancy and are a substantial cost burden to health care systems. Physically active individuals and professional athletes are not risk free for developing this condition. Although the percentage of persons affected is substantially lower than the general population, these individuals still need to be thoroughly evaluated and blood pressure targets monitored to allow safe competitive sports participation. Regarding treatment, lifestyle modification measures should be routinely emphasized to athletes and active individuals with the same importance as for the general population. Medication treatment can be complicated because of restrictions by athletic organizations and possible limitations on maximal exercise performance. In addition, the choice of an antihypertensive drug should be made with consideration for salt and water losses that routinely occur in athletes, as well as preservation of exercise performance and endothelial function. First-line therapies for athletes and physically active individuals may be different from the general population. Some authorities believe that blocking the renin-angiotensin system with angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) is more beneficial compared with diuretics because of ACE inhibitors and ARBs being able to avoid salt and water losses. Dihydropyridine calcium channel blockers (CCBs) are another reasonable choice. Despite effects on heart rate, nondihydropyridine CCBs do not appear to impair exercise performance. beta-Blockers are not used as a first-line therapy in athletes because of effects on exercise and prohibition by the National Collegiate Athletic Association and World Anti-Doping Agency in certain sports. In this article, we address the evidence on hypertension and its related treatments in active individuals to provide recommendations that allow the best competitive sports results and reduce cardiovascular risk.

An application of meta-analysis techniques in the evaluation of adverse experiences with antihypertensive agents

PURPOSE

To investigate the profiles of adverse events (AEs) in randomized controlled trials of antihypertensive agents therapy with the technique of meta-analysis.

METHODS

A total of 620 articles were selected from MEDLINE, EMBASE, JAPIC-DOC, JMEDICINE and manual searching. Two independent reviewers examined the 620 selected articles according to the following criteria: (1) the methods of randomization, (2) making for allocating treatments, (3) therapeutic class of drugs, (4) sample sizes, (5) duration of the treatment, (6) primary endpoint, (7) reporting method for all adverse events, (8) method of monitoring AEs, and (9) incidence rates of all reported AEs. To combine the risk difference and risk ratios of incidence between CCBs and beta blockers or diuretics, the method of DerSimonian and Laird based on random effect model was applied.

RESULTS

A total of 3073 patients were included in this meta-analysis of serious adverse events (SAEs). There was no significant difference in the total incidence of SAEs between CCBs and diuretics or between CCBs and beta blockers. We found that patients treated with CCBS had 0.14% fewer SAEs compared with the patients treated with diuretics. Contrarily, the patients treated with CCBs had 0.29% more SAEs compared with the patients treated with beta blockers. There was a significant difference between the patients treated with CCBs and those treated with diuretics in the symptoms with headache and oedema. With respect to the comparison between CCBs and beta blockers, flushing occurred 8.75% more frequently in the CCBs group than in the beta blockers group.

CONCLUSION

A meta-analysis can be applied to safety analyses of data obtained in clinical trials if all of the RCT articles used include a complete description of adverse experiences.

Optimization of antihypertensive therapy with a novel, extended-release formulation of diltiazem: results of a practice-based clinical study

Although the effectiveness of diltiazem for the treatment of patients with hypertension has been well demonstrated in numerous placebo-controlled and comparative clinical trials, most physicians have had some concern about its efficacy and have used it predominantly in patients with mild hypertension. Few large-scale studies have evaluated the efficacy and safety of higher dosages of diltiazem for the treatment of patients with hypertension, and few have evaluated the use of diltiazem in patients with more severe hypertension. Tiazac (Forest Pharmaceuticals, Inc., St. Louis, Missouri), a new, extended-release formulation of diltiazem, provides 24-hour blood pressure control with a single daily dose of up to 360 mg. The Study of Titration and Response to Tiazac (START) is an ongoing practice-based, open-label, multicenter study designed to evaluate the efficacy and safety profiles of Tiazac at greater-than-traditional doses in hypertensive patients and to assess the ability of Tiazac to decrease the rate-pressure product, a surrogate marker for cardiac workload. Patients were eligible for study entry whether their hypertension was newly diagnosed or previously treated with a different formulation of diltiazem or any other antihypertensive agent. Normotensive (sitting diastolic blood pressure [SDBP] < 90 mm Hg) subjects and those with mild (SDBP 90 to 99 mm Hg), moderate (SDBP 100 to 109 mm Hg), severe (SDBP 110 to 119 mm Hg), and very severe (SDBP > or = 120 mm Hg) hypertension were assessed at baseline (visit 1), visit 2 (10 to 14 days after visit 1), and visit 3 (25 to 28 days after visit 1). A total of 3082 patients were enrolled, and data from 2802 assessable patients (i.e., those who completed visits 1, 2, and 3) were analyzed. No subjects were lost to follow-up as a result of adverse effects. All subjects received a starting dose of Tiazac 180 mg or 240 mg once daily, and doses were titrated upward to 360 mg once daily as clinically indicated. Blood pressure reduction matched the severity of hypertension in all patients. Subjects who were switched from another diltiazem formulation demonstrated further decreases in SDBP. Antihypertensive monotherapy with Tiazac was well tolerated. This interim START report demonstrates that a daily dose of up to 360 mg of diltiazem is optimal in terms of both control of hypertension and patient compliance. It also provides the practice-based physician with useful clinical information on dose titration and response to a new formulation of an approved drug and supports the efficacy and safety profiles of diltiazem documented in previous well-controlled clinical trials.

Persistence of anti-hypertensive effect after 'missed doses' of calcium antagonist with long (amlodipine) vs short (diltiazem) elimination half-life

1. Calcium antagonists with long vs short elimination half-life may show marked differences in their antihypertensive effect during short interruptions of therapy by missed doses. 2. In the present study we evaluated the blood pressure lowering effect of amlodipine vs diltiazem both on active maintenance treatment and after active treatment was interrupted for 2 days by placebo using a double-blind randomized design. After a single blind placebo run-in period, hypertensive patients were randomized to amlodipine 5 mg once daily or diltiazem 90 mg twice daily. After 4-6 weeks, doses were increased to 10 mg once daily or 180 mg twice daily, if necessary for control of diastolic blood pressure. During week 9 or 10 on active treatment blisterpacks contained 2 days of placebo. Twenty-four hour blood pressure monitoring was performed at the end of run-in period and during week 9 and 10 on active vs interrupted therapy. 3. Active therapy by amlodipine (n = 20) lowered day systolic blood pressure by 17 +/- 2 mmHg and diastolic blood pressure by 12 +/- 2 mmHg and did not change heart rate. In second day of interrupted therapy most of these responses were still present. Diltiazem (n = 14) lowered day systolic blood pressure by 13 +/- 2 mmHg, diastolic blood pressure by 11 +/- 2 mmHg and heart rate by 10 +/- 2 beats min-1. Most of these responses had disappeared during the second day of interrupted therapy. 4. We conclude that amlodipine and diltiazem are fairly similar in lowering blood pressure from an efficacy point of view. However, during short periods of noncompliance blood pressure control will persist markedly better with the agent with a long vs the one with a short elimination half-life.

Effects of felodipine, metoprolol and their combination on blood pressure at rest and during exercise and on volume regulatory hormones in hypertensive patients

The effects on blood pressure (BP) and heart rate (HR), at rest and during bicycle exercise, of the vascular selective calcium antagonist felodipine, the cardio-selective beta-blocker metoprolol, and of the two drugs in combination, were assessed in a double-blind, three-way cross-over study comprising 23 patients with essential, mild to moderate hypertension. All three treatment regimens were given to each patient in randomised order for 4 weeks after a 4 week placebo run-in period. Felodipine 10-20 mg daily, metoprolol 100-200 mg daily and the combination of felodipine 10-20 mg plus metoprolol 100 mg daily were all effective antihypertensive treatments both at rest and during exercise. The two drugs seemed to have additive effects and the effect on BP of the combination was greater than that of either drug given as monotherapy. The mean sitting BP was 148/103 mmHg at randomisation, after 4 weeks of placebo treatment, and 134/88, 134/94 and 121/84 mmHg, respectively, after 4 weeks' treatment with felodipine, metoprolol and the combination. Maximal exercise capacity was similar irrespective of treatment regimen, and the normal response to exercise BP and HR was maintained during all active treatments. Changes observed in volume regulatory hormones (PRA, aldosterone and ANP) were consistent with a direct tubular natriuretic-diuretic effect of felodipine and of beta-blocker attenuated release of renin. All treatment regimens were well tolerated and adverse events reported were usually mild and transient.

Diltiazem: ten years of clinical experience in the treatment of hypertension

Diltiazem hydrochloride is a benzothiazepine derivative calcium-channel blocker with proven antianginal and antihypertensive capabilities. Its primary mechanism of action is vasodilatation, which results in diminished vascular resistance and improved perfusion to various vascular beds and target organs. The antihypertensive efficacy of diltiazem in various demographic groups has been studied and compared with diuretics, beta-blockers, angiotensin-converting enzyme inhibitors, and other calcium-channel blockers. These studies have shown that the antihypertensive effect of diltiazem is similar to that of the other therapies. Diltiazem does not adversely affect electrolytes or carbohydrate or lipid metabolism, and it may have beneficial effects on the heart and kidneys. Diltiazem reduces myocardial hypertrophy and exerts antianginal effects on the heart through coronary vasodilation and reduction in the blood pressure double product. Diltiazem improves renal perfusion and attenuates proteinuria. These effects may be helpful in limiting the progression of renal injury. Overall, the efficacy and tolerability of diltiazem, as well as its salutary effects on the heart and kidneys, make it an important therapeutic consideration for patients with hypertensive disease.

Management of Hypertension

In brief Current recommendations for brief managing mild to very severe high blood pressure need to be adapted for the special concerns of physically active patients. First-line treatment involves dietary changes, smoking cessation, and aerobic exercise. The next step is to add drug therapy, and diuretics and beta-blockers are the initial drugs of choice because of their proven long-term efficacy. Diuretics may, however, produce hypokalemia or dehydration, and beta- blockers may cause hyperkalemia, reduce exercise capacity, or increase perceived exertion. Other antihypertensive agents may be preferable in specific situations.

A new extended-release formulation of diltiazem HCl for the treatment of mild-to-moderate hypertension

Calcium-channel blockers are a safe and effective treatment modality and have been used extensively in the treatment of angina and hypertension. Dilacor XR capsules, a new extended-release formulation of diltiazem, has been developed for the treatment of hypertension. Dilacor XR (Rhône-Poulenc Rorer Pharmaceuticals Inc., Collegeville, PA) uses a novel drug delivery system, the Geomatrix (JAGO Research AG, Zollikon, Switzerland) controlled-release system, to deliver diltiazem at a constant rate for 24 hours. The rate of absorption is also slower. As doses of Dilacor XR were increased from 120 mg to 540 mg/day, there were disproportionate increases observed in area under the curve, maximum peak plasma concentration, minimum peak plasma concentration, and average peak plasma concentration. The efficacy data from two clinical trials have confirmed the established efficacy of diltiazem and the 24-hour efficacy of Dilacor XR in the control of mild-to-moderate hypertension. The incidence of adverse effects with Dilacor XR in doses as high as 540 mg/day was generally comparable to that of placebo. This new extended-release formulation of diltiazem should significantly facilitate blood pressure control because of better patient compliance with a once daily regimen.

Clinical experience with a once-daily, extended-release formulation of diltiazem in the treatment of hypertension

Although calcium channel blockers were only recently approved for antihypertensive therapy, 10 years of data have demonstrated their beneficial effects. Among the available calcium channel blockers, diltiazem hydrochloride appears to have a highly favorable side-effect profile. A new, extended-release formulation of diltiazem has been developed for the treatment of essential hypertension. The safety and efficacy of various once-daily doses of this new formulation were assessed in two multicenter studies. The first study was a dose-ranging trial of 275 patients with mild-to-moderate hypertension. Patients were randomly assigned to once-daily diltiazem (120, 240, 360, or 480 mg) or placebo for a 4-week, double-blind treatment period. A patient subgroup underwent ambulatory blood pressure monitoring (ABPM) twice. Once-daily diltiazem (dose range, 240-480 mg) significantly lowered trough systolic and diastolic blood pressure in a clearly dose-related fashion. ABPM results demonstrated consistent decreases in systolic and diastolic blood pressure throughout the 24-hour dosing interval. Dosages greater than or equal to 240 mg/day provided trough drug blood levels within the therapeutic range (i.e., greater than or equal to 40 ng/mL). The second study was a forced-escalation trail of 115 patients with mild-to-moderate hypertension. Patients were randomized to treatment with either placebo or escalating dosages of diltiazem (180 mg/day for 2 weeks, 360 mg/day for 2 weeks, and then 540 mg/day for 2 weeks). Statistically significant (p less than 0.01) reductions in supine systolic and diastolic blood pressure were observed with the 360 mg/day and 540 mg/day dosages. Dose escalations resulted in incremental blood pressure reductions and an increase in the percentage of responders. There was a significant correlation between diltiazem peak and trough plasma concentrations and antihypertensive effects in both studies, supporting the 24-hour efficacy of this extended-release formulation. Diltiazem administered once daily was found to be safe and well tolerated by the patients in these studies; adverse events were generally mild, with an incidence similar to placebo. Results indicate that this new extended-release formulation of diltiazem, administered once daily in doses greater than 120 mg, effectively lowers systolic and diastolic blood pressure in patients with mild-to-moderate essential hypertension.

Exercise tolerance with nebivolol and atenolol

Patients treated with beta-blocking agents often complain of fatigue during exercise. Exercise capacity is decreased under this condition. Nebivolol is a new beta 1-adrenoceptor antagonist with a particular hemodynamic profile, which might be due to an ancillary property. Five milligrams once daily seems the optimal dose for antihypertensive treatment. In a double-blind, placebo-controlled crossover study, the effects of nebivolol on maximal and endurance exercise capacity are compared with those of atenolol in healthy volunteers. The hemodynamic and metabolic effects during exercise are also studied. Nebivolol 5 mg once daily and atenolol 100 mg once daily decrease blood pressure at rest similarly. At these dosages nebivolol shows a smaller decrease in heart rate than atenolol. During exercise, the rise in systolic blood pressure and heart rate is less depressed with nebivolol than with atenolol. In contrast to atenolol, nebivolol does not decrease maximal and endurance exercise capacity, and does not increase perceived exertion significantly. Changes in hemodynamics influence maximal exercise capacity. Since nebivolol has less effect on exercise hemodynamics than atenolol, this might explain why maximal work capacity is not changed during nebivolol. During endurance exercise metabolic effects are thought to be more important. Under nebivolol glycerol and NEFA production is less depressed during exercise and might explain the preserved endurance capacity. These data suggest less beta blockade during nebivolol than during atenolol at the dosages used in this study. In conclusion, at a dose known to be antihypertensive, nebivolol does not alter exercise capacity significantly in healthy volunteers.

Twenty-four hour ambulatory blood pressure profile of a new slow-release formulation of diltiazem in mild to moderate hypertension

Twelve patients with a mild to moderate essential hypertension were included in a double-blind, balanced, randomized placebo-controlled cross-over study to assess the efficacy and duration of action of a new slow-release formulation of diltiazem (300 mg) given once daily for 3 weeks. All office blood pressure measurements were done 24 hours after drug intake. In order to improve the accuracy of the trial, 24-hours non-invasive ambulatory blood pressure monitoring (Spacelabs 90207 system) were performed as well. Diltiazem significantly lowered supine and standing systolic and diastolic office blood pressure (by 16.9/12.7 mmHg and by 17.3/13.8 mmHg, respectively), without changing office heart rate. Diltiazem also significantly lowered ambulatory blood pressure measured over 24 hours, as well as ambulatory heart rate. The blood pressure lowering effect was most pronounced during the daytime period and did not reach statistical significance during the sleeping hours. The treatment was well tolerated, and there were no significant side effects. The results confirm the antihypertensive efficacy of diltiazem LP 300 mg once daily during the daytime and during the early morning blood pressure rise, without inducing nocturnal hypotension.

Exercise prescription for hypertensive patients

Physical conditioning has been suggested as a useful adjunct or alternative to pharmacologic therapy in the treatment of borderline or mild hypertension. This recommendation stems from numerous studies that have demonstrated modest decreases in blood pressure in hypertensive individuals. Exercise guidelines should be based on preliminary exercise testing and modified to accommodate those patients who are taking a variety of antihypertensive medications. Although pure isometric exercise is generally contraindicated in hypertensive patients, potentially valuable training activities that involve a substantial static component, including arm crank ergometry and mild-to-moderate load weight training, probably requires individual assessment.

Hypertension

In brief When exercise alone does not NMM control hypertension, a medical ISMS regimen can be used in conjunction with exercise or other nonpharmacologic interventions. Diuretics, beta blockers, calcium antagonists, and angiotensin-converting enzyme (ACE) inhibitors are widely used to treat hypertension. ACE inhibitors and calcium antagonists are good choices for exercising patients because they do not limit exercise performance and have few side effects. The author gives guidelines for changing the regimen from exercise alone to exercise and medication, and for stepping down from medical therapy.

Calcium metabolism, calcium-channel blocking agents, and hypertension management

Increasing evidence has suggested that a disturbance of cellular calcium metabolism may have a role in initiating and maintaining elevated systemic vascular resistance in essential hypertension. Controversy exists over whether calcium can alleviate or exacerbate the hypertensive process, and diversity of calcium metabolism in hypertensive patients has been proposed. Calcium-channel blocking agents are potent vasodilators capable of correcting the elevated systemic vascular resistance. Clinical studies have shown that these drugs have antihypertensive efficacy comparable to established agents. The elderly, blacks, and patients with low renin activity respond well to calcium-channel blockers. These drugs may also offer potential advantages over established antihypertensive agents in patients with other coexisting diseases. Sustained release formulations have been developed, and initial experience with long-term efficacy and tolerability is encouraging. The calcium-channel blockers may become first-line therapy for treatment of hypertension in selected patients.

Calcium channel blockers in systemic hypertension

Alterations in transmembrane flux of calcium ions may be playing a role in the pathophysiology of systemic hypertension. Calcium channel blockers have been shown to be effective antihypertensive drugs with excellent safety profiles. They are efficacious in the long term treatment of systemic hypertension in all population subgroups, and have special applicability for treating patients with hypertensive urgencies and individuals with concomitant diseases such as angina pectoris and arrhythmias.

Calcium channel antagonists. Part III: Use and comparative efficacy in hypertension and supraventricular arrhythmias. Minor indications

The major antihypertensive mechanism of calcium antagonists is by decreasing the systemic vascular resistance, modified by the counter-regulatory responses of the baroreflexes and the renin-angiotensin-aldosterone system. In severe hypertension, the concept that calcium overload of the vascular myocyte could precipitate or aggravate peripheral vasoconstriction provides a logical basis for the use of these agents as first choice therapy; nifedipine, especially, has been well tested. As monotherapy for mild to moderate hypertension each of the three first-generation agents compares well with beta-blockers. Calcium antagonists may have a special role in the therapy of certain patient groups (elderly, black) or in those subjects whose life style involves intense physical or mental exertion (hemodynamics better maintained than with beta-blockade) or in patients with early end-organ damage such as left ventricular hypertrophy or renal insufficiency. However, the goal blood pressure may not be reached during monotherapy so that drug combinations may be required. Further indications for these compounds are as follows. Verapamil and diltiazem are frequently used in supraventricular tachycardias including acute and chronic atrial fibrillation. In the arrhythmias of the Wolff-Parkinson-White syndrome, there is the potential danger of provocation of anterograde conduction. Further indications for calcium antagonists, still under evaluation, include congestive heart failure (controversial), hypertrophic cardiomyopathy (verapamil), primary pulmonary hypertension (high doses required), Raynaud's phenomenon (nifedipine and diltiazem effective), peripheral vascular disease (proof not yet documented), cerebral insufficiency and subarachnoid hemorrhage (nimodipine promising), migraine, exertional bronchospasm, renal disease, atherosclerosis (experimental), and primary aldosteronism (nifedipine inhibits aldosterone release). Second-generation agents include dihydropyridines, such as nitrendipine, nicardipine, felodipine, amlodipine, nisoldipine, nimodipine, and isradipine. From these will be selected agents that are longer acting and provide higher vascular selectivity. New preparations of existing agents include slow-release formulations of nifedipine, verapamil, and diltiazem. Minor side effects include those caused by vasodilation (flushing and headaches), constipation (verapamil), and ankle edema. Serious side effects are rare and result from improper use of these agents, as when intravenous verapamil is given to patients with sinus or atrioventricular nodal depression from drugs or disease, or nifedipine to patients with aortic stenosis. The potential of a marked negative inotropic effect is usually offset by afterload reduction, especially in the case of nifedipine. Yet caution is required when calcium antagonists, especially verapamil, are given to patients with myocardial failure unless caused by hypertensive heart disease. Drug interactions of calcium antagonists occur with other cardiovascular agents such as alpha-adrenergic blockers, beta-adrenergic blockers, digoxin, quinidine, and disopyramide.(ABSTRACT TRUNCATED AT 400 WORDS)

Efficacy and safety of sustained-release diltiazem as replacement therapy for beta blockers and diuretics for stable angina pectoris and coexisting essential hypertension: a multicenter trial

To determine if a sustained-release form of the calcium entry blocker diltiazem would be a satisfactory substitute for the combination of beta-adrenergic blocking agent and thiazide diuretic in the treatment of systemic hypertension and angina pectoris, 38 patients were studied in a 4-center trial. Blood pressure and heart rate were measured in the supine position, immediately after and 5 minutes after standing. Modified Bruce protocol treadmill tests were performed to determine the time to onset of 1 mm ST-segment depression, time to onset of chest pain and time to termination of exercise. Diltiazem monotherapy resulted in equivalent blood pressure control in 28 of 38 patients (74%). In the remaining patients, blood pressure control was achieved with resumption of the diuretic. Blood pressure with beta blocker plus diuretic compared with diltiazem were, in the supine position 137 +/- 22/82 +/- 7 (+/- 1 standard deviation) versus 139 +/- 22/82 +/- 8 mm Hg, immediately after standing 131 +/- 20/84 +/- 9 versus 133 +/- 21/82 +/- 10 mm Hg and after standing for 5 minutes 134 +/- 19/85 +/- 8 versus 137 +/- 18/85 +/- 9 mm Hg (difference not significant for each). The heart rate with diltiazem was higher supine (67 +/- 11 versus 60 +/- 11 beats/min), standing (73 +/- 13 versus 64 +/- 14 beats/min) and 5 minutes after standing (73 +/- 14 versus 63 +/- 14 beats/min, p less than 0.01 for each).(ABSTRACT TRUNCATED AT 250 WORDS)

Demographic considerations in the selection of antihypertensive therapy

Because of the growing number of antihypertensive agents that are suitable for initial therapy in mild and moderate hypertension, it is important to identify factors that influence the response to various medications. Although individual patient considerations, such as associated illnesses and potential side effects, are of primary importance in choosing therapy, the influence of demographic factors has received increasing attention. The effect of age, race and gender on the response to antihypertensive therapy will be examined. Several studies have indicated that the beta blockers and angiotensin converting enzyme (ACE) inhibitors are more effective in younger than in older patients. Conversely, there is a trend toward greater responses in older subjects to the diuretics and calcium antagonists. In the few studies available that have compared agents in various classes, it appears that diuretics, and probably calcium antagonists, are significantly more effective than beta blockers or ACE inhibitors in patients over 60 years of age. However, the interdrug differences in young patients are probably less important. With regard to race, the relative lack of effect of beta blockers and ACE inhibitors in blacks is well accepted; in comparative studies, diuretics proved significantly better. From the few available studies, it does not appear that the calcium antagonists are more potent in either racial group, but they may be superior to the beta blockers and ACE inhibitors in blacks. Far less information is available concerning differences in antihypertensive responses between men and women. There is some suggestion that women may be less responsive to beta blockers than men.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of diltiazem and atenolol in young, physically active men with essential hypertension

The antihypertensive efficacy and effect on maximal exercise performance of diltiazem was evaluated and compared with atenolol in patients specifically selected on the basis of their being young and physically active. Diltiazem (sustained-release preparation, 90 mg twice daily) was administered to 14 patients (aged 33 +/- 2 years) and atenolol (50 mg once daily) to 13 patients (aged 30 +/- 2 years) with essential hypertension in a 16-week randomized, double-blind, parallel study. The 2 drugs had comparable antihypertensive effects at rest, with mean decreases of 18 and 17 mm Hg (p less than 0.001) for supine and standing diastolic blood pressure (BP), respectively, during diltiazem treatment, and mean decreases of 21 and 18 mm Hg (p less than 0.001) during atenolol treatment. During maximal graded exercise testing, systolic BP, diastolic BP, heart rate and heart rate-BP product were significantly reduced by both drugs. However, the reductions in systolic BP, heart rate and heart rate-BP product during exercise were considerably greater (p less than 0.001) with atenolol than with diltiazem. Maximal exercise performance was essentially unchanged with diltiazem and slightly (3%, p less than 0.05) reduced with atenolol. Thus, diltiazem is effective and well-tolerated single therapy for young patients with mild to moderate essential hypertension who lead a physically active life style and compares favorably with atenolol.

The athlete's heart syndrome

The athlete's heart is a benign condition, associated with physiologic alterations that can be detected on physical and laboratory examination. Echocardiography is a particularly useful technique is quantitating cardiac adaptation to exercise training and in screening for cardiovascular disorders that can be deleterious to the athlete. Cardiomyopathies are common causes of sudden death in young athletes, and myocarditis in physically-active young military recruits. Coronary disease is usually implicated in middle-aged athletes such as distance runners. Recent well-publicized deaths in several athletes have focused more attention on the need to detect Marfan's syndrome and cocaine use. Published guidelines such as the 16th Bethesda Conference and recent medical advances like new antihypertensive and antiarrhythmic drugs assist the clinician in counseling and managing athletes with cardiovascular disorders.