Effect of theophylline on the warm-up phenomenon

This study examined whether the adenosine receptor antagonist theophylline prevents the warm-up phenomenon in patients with stable angina undergoing serial exercise tests. Our findings offer evidence that adenosine does not play a role in the warm-up phenomenon, and indirectly suggest that the warm-up phenomenon does not represent ischemic preconditioning in humans.

Neuroendocrine activation in heart failure is modified by endurance exercise training

OBJECTIVES

The purpose of this study was to determine whether endurance exercise training could buffer neuroendocrine activity in chronic heart failure patients.

BACKGROUND

Neuroendocrine activation is associated with poor long-term prognosis in heart failure. There is growing consensus that exercise may be beneficial by altering the clinical course of heart failure, but the mechanisms responsible for exercise-induced benefits are unclear.

METHODS

Nineteen heart failure patients (ischemic disease; New York Heart Association [NYHA] class II or III) were randomly assigned to either a training group or to a control group. Exercise training consisted of supervised walking three times a week for 16 weeks at 40% to 70% of peak oxygen uptake. Medications were unchanged. Neurohormones were measured at study entry and after 16 weeks.

RESULTS

The training group (n = 10; age = 61 +/- 6 years; EF = 30 +/- 6%) and control group (n = 9; age = 62 +/- 7 years; EF = 29 +/- 7%) did not differ in clinical findings at study entry. Resting levels of angiotensin II, aldosterone, vasopressin and atrial natriuretic peptide in the training and control groups did not differ at study entry (5.6 +/- 1.3 pg/ml; 158 +/- 38 pg/ml; 6.1 +/- 2.0 pg/ml; 37 +/- 8 pg/ml training group vs. 4.8 +/- 1.2; 146 +/- 23; 4.9 +/- 1.1; 35 +/- 10 control group). Peak exercise levels of angiotensin II, aldosterone, vasopressin and atrial natriuretic peptide in the exercise and control groups did not differ at study entry. After 16 weeks, rest and peak exercise hormone levels were unchanged in control patients. Peak exercise neurohormone levels were unchanged in the training group, but resting levels were significantly (p < 0.001) reduced (angiotensin -26%; aldosterone -32%; vasopressin -30%; atrial natriuretic peptide -27%).

CONCLUSIONS

Our data indicate that 16 weeks of endurance exercise training modified resting neuroendocrine hyperactivity in heart failure patients. Reduction in circulating neurohormones may have a beneficial impact on long-term prognosis.

Therapeutic benefit. Aspirin revisited in light of the introduction of clopidogrel

BACKGROUND

Antiplatelet agents are widely recognized for their efficacy in reducing the occurrence of vascular events in patients with atherothrombotic disease. Aspirin is currently considered to be the "reference standard" antiplatelet agent and is recommended by the American Heart Association for use in patients with a wide range of manifestations of cardiovascular disease on the basis of its high benefit-to-risk and benefit-to-cost ratios. Recently, clopidogrel (Plavix, Bristol-Myers Squibb Co), another antiplatelet agent, was approved by the Food and Drug Administration for many of the same indications as aspirin.

SUMMARY OF REVIEW

Because physicians will be faced with deciding whether to switch from the well-established practice of recommending aspirin for use in patients with atherothrombotic disease, both aspirin and clopidogrel are compared with respect to the primary factors that influence such decisions (ie, their relative efficacy, safety, cost, and convenience of use).

CONCLUSIONS

Based on the available evidence, aspirin is preferred for the majority of stroke or myocardial infarction patients at risk of recurrent atherothrombotic events. Clopidogrel may, however, provide valuable therapeutic benefit over aspirin in patients with peripheral arterial disease and in stroke or myocardial infarction patients for whom aspirin treatment is contraindicated or for whom aspirin fails to achieve the desired therapeutic effect.

A controlled trial with a novel anti-ischemic agent, ranolazine, in chronic stable angina pectoris that is responsive to conventional antianginal agents. Ranolazine Study Group

We assessed efficacy and safety of a new anti-ischemic agent, ranolazine, during a randomized, double-blind, placebo-controlled crossover study. In the qualifying phase, we withdrew at least 1 antianginal drug from the drug regimen of 312 patients with chronic stable angina while they took placebo. After exercise time had shortened by > or =1.0 minute, we randomly assigned patients to receive either immediate-release ranolazine in 3 dosing regimens or placebo during each treatment period. After each week of treatment, we measured exercise tolerance and ranolazine plasma concentrations at both peak and trough. All exercise parameters significantly (p< or =0.02) improved (intention-to-treat analysis) with ranolazine (all regimens combined) at mean peak plasma concentrations ranging from 1,576 to 2,492 ng/ml compared with placebo without differences in double product. Although similar trends persisted at mean trough, plasma concentrations (range 275 to 602 ng/ml), only the time to 1.0 mm ST-segment depression remained statistically significant. In conclusion, immediate-release ranolazine is effective and well tolerated. However, this immediate-release short-acting formulation with this dosing regimen is not adequate for continuous protection. Either larger or more frequent doses or a sustained-release formulation would be required for clinical use.

Low hot pain threshold predicts shorter time to exercise-induced angina: results from the psychophysiological investigations of myocardial ischemia (PIMI) study

OBJECTIVES

The purpose of this study was to test whether cutaneous thermal pain thresholds are related to anginal pain perception.

BACKGROUND

Few ischemic episodes are associated with angina; symptoms have been related to pain perception thresholds.

METHODS

A total of 196 patients with documented coronary artery disease underwent bicycle exercise testing and thermal pain testing. The Marstock test of cutaneous sensory perception was administered at baseline after 30 min of rest on two days and after exercise and mental stress. Resting hot pain thresholds (HPTs) were averaged for the two baseline visits and divided into two groups: 1) average HPT <41 degrees C, and 2) average HPT > or =41 degrees C, to be clearly indicative of abnormal hypersensitivity to noxious heat.

RESULTS

Patients with HPT <41 degrees C had significantly shorter time to angina onset on exercise testing than patients with HPT > or =41 degrees C (p < 0.04, log-rank test). Heart rates, systolic blood pressure and rate-pressure product at peak exercise were not different for the two groups. Resting plasma beta-endorphin levels were significantly higher in the HPT <41 degrees C group (5.9+/-3.7 pmol/liter vs. 4.7+/-2.8 pmol/liter, p = 0.02). Using a Cox proportional hazards model, patients with HPT <41 degrees C had an increased risk of angina (p = 0.03, rate ratio = 2.0). These differences persisted after adjustment for age, gender, depression, anxiety and history of diabetes or hypertension (p < 0.01).

CONCLUSIONS

Occurrence of angina and timing of angina onset on an exercise test are related to overall hot pain sensory perception. The mechanism of this relationship requires further study.

Coronary flow velocity response to adenosine characterizes coronary microvascular function in women with chest pain and no obstructive coronary disease. Results from the pilot phase of the Women's Ischemia Syndrome Evaluation (WISE) study

OBJECTIVES

We sought to develop and validate a definition of coronary microvascular dysfunction in women with chest pain and no significant epicardial obstruction based on adenosine-induced changes in coronary flow velocity (i.e., coronary velocity reserve).

BACKGROUND

Chest pain is frequently not caused by fixed obstructive coronary artery disease (CAD) of large vessels in women. Coronary microvascular dysfunction is an alternative mechanism of chest pain that is more prevalent in women and is associated with attenuated coronary volumetric flow augmentation in response to hyperemic stimuli (i.e., abnormal coronary flow reserve). However, traditional assessment of coronary volumetric flow reserve is time-consuming and not uniformly available.

METHODS

As part of the Women's Ischemia Syndrome Evaluation (WISE) study, 48 women with chest pain and normal coronary arteries or minimal coronary luminal irregularities (mean stenosis = 7%) underwent assessment of coronary blood flow reserve and coronary flow velocity reserve. Blood flow responses to intracoronary adenosine were measured using intracoronary Doppler ultrasonography and quantitative angiography.

RESULTS

Coronary volumetric flow reserve correlated with coronary velocity reserve (Pearson correlation = 0.87, p < 0.001). In 29 (60%) women with abnormal coronary microcirculation (mean coronary flow reserve = 1.84), adenosine increased coronary velocity by 89% (p < 0.001) but did not change coronary cross-sectional area. In 19 (40%) women with normal microcirculation (mean flow reserve = 3.24), adenosine increased coronary velocity and area by 179% (p < 0.001) and 17% (p < 0.001), respectively. A coronary velocity reserve threshold of 2.24 provided the best balance between sensitivity and specificity (90% and 89%, respectively) for the diagnosis of microvascular dysfunction. In addition, failure of the epicardial coronary to dilate at least 9% was found to be a sensitive (79%) and specific (79%) surrogate marker of microvascular dysfunction.

CONCLUSIONS

Coronary flow velocity response to intracoronary adenosine characterizes coronary microvascular function in women with chest pain in the absence of obstructive CAD. Attenuated epicardial coronary dilation response to adenosine may be a surrogate marker of microvascular dysfunction in women with chest pain and no obstructive CAD.

Influence of smoking status on angiotensin-converting enzyme inhibition-related improvement in coronary endothelial function. TREND Investigators. Trial on Reversing Endothelial Dysfunction

Our study evaluated the influence of smoking status on coronary endothelial function in normotensive patients with coronary artery disease who received placebo or the angiotensin-converting enzyme inhibitor quinapril in the TREND study (Trial on Reversing Endothelial Dysfunction). In this retrospective analysis of data from the previously published study, patients were classified as either smokers (n = 23) or nonsmokers (n = 82). Patients underwent coronary angiography at baseline and again after 6-month follow-up. The primary response variable was the net change in acetylcholine-induced diameter of the target coronary artery segments (n = 105) between the baseline and 6-month follow-up angiograms. The secondary response variables were based on analysis of all segments (n = 300) and the mean diameter responses of target and all segments at 6 months. At baseline, coronary artery vasomotor responses were similar in smokers and nonsmokers in the placebo and quinapril groups. There was a significant improvement in the primary response variable for both smokers (P = 0.008) and nonsmokers (P = 0.047) randomized to quinapril compared with placebo. At 6-month follow-up, nonsmokers in the placebo group showed no significant change in the mean vasoconstrictor responses (8.3% vs. 8.0% at acetylcholine 10(-4) mol/L), whereas nonsmokers in the quinapril-treated group showed significantly less vasoconstriction (2.7% vs. 13.2%; P = 0.003). Among smokers in the placebo group, vasoconstriction increased nonsignificantly (21.7% vs. 17.2% at baseline) but decreased significantly in the quinapril group (0.5% vs. 17.9%; P = 0.002). These results indicate that ACE inhibition improves the coronary vasomotor response in both smokers and nonsmokers, but that smokers apparently derive greater benefit.

Dobutamine stress echocardiography in women with chest pain. Pilot phase data from the National Heart, Lung and Blood Institute Women's Ischemia Syndrome Evaluation (WISE)

OBJECTIVES

The aim of this project was to assess the utility of dobutamine stress echocardiography (DSE) for evaluation of women with suspected ischemic heart disease.

BACKGROUND

Most investigations addressing efficacy of diagnosis and treatment of coronary artery disease (CAD) have been performed in predominantly male populations. As part of the Women's Ischemia Syndrome Evaluation (WISE) study, DSE was assessed in women participating at the University of Florida clinical site.

METHODS

Women with chest pain or other symptoms suggestive of myocardial ischemia and clinically indicated coronary angiography were eligible for the WISE study. Enrolled subjects underwent DSE using a modified protocol. Coronary stenosis was assessed by core laboratory quantitative coronary angiography (QCA).

RESULTS

The 92 women studied ranged in age from 34 to 82 years (mean 57.5). All women had > or = 1 major risk for CAD, and most (89, 97%) had > or = 2 risk factors. In 78 women (85%), left ventricular wall motion was normal at baseline and during peak infusion. The remaining 14 women had wall motion abnormalities during DSE. By QCA, 25 women (27%) had > or = 50% coronary stenosis, including 10 with single-vessel obstruction. Dobutamine stress echocardiography was abnormal in 10 of these 25 women, yielding overall sensitivity of 40%, and 60% for multivessel stenosis. Exclusion of women with inadequate heart rate response yielded overall sensitivity of 50%, and 81.8% for multivessel stenosis. Dobutamine stress echocardiography was normal in 54 of the 67 women with < 50% coronary narrowing, specificity 80.6%.

CONCLUSIONS

Dobutamine stress echocardiography reliably detects multivessel stenosis in women with suspected CAD. However, DSE is usually negative in women with single-vessel stenosis, and in the larger subset without coronary stenosis. Ongoing protocols of the WISE study are expected to improve diagnostic accuracy in women with single-vessel disease, as well as provide important data in the substantial number of women with chest pain but without epicardial coronary artery stenosis.

Relationship among mental stress-induced ischemia and ischemia during daily life and during exercise: the Psychophysiologic Investigations of Myocardial Ischemia (PIMI) study

OBJECTIVES

The purposes of this database study were to determine: 1) the relationship between mental stress-induced ischemia and ischemia during daily life and during exercise; 2) whether patients who exhibited daily life ischemia experienced greater hemodynamic and catecholamine responses to mental or physical stress than patients who did not exhibit daily life ischemia, and 3) whether patients who experienced daily life ischemia could be identified on the basis of laboratory-induced ischemia using mental or exercise stress testing.

BACKGROUND

The relationships between mental stress-induced ischemia in the laboratory and ischemia during daily life and during exercise are unclear.

METHODS

One hundred ninety-six stable patients with documented coronary disease and a positive exercise test underwent mental stress testing and bicycle exercise testing. Radionuclide ventriculography and electrocardiographic (ECG) monitoring were performed during the mental stress and bicycle tests. Patients underwent 48 h of ambulatory ECG monitoring. Hemodynamic and catecholamine responses were obtained during mental stress and bicycle tests.

RESULTS

Ischemia (reversible left ventricular dysfunction or ST segment depression > or = 1 mm) developed in 106 of 183 patients (58%) during the mental stress test. There were no significant differences in clinical characteristics of patients with, compared with those without, mental stress-induced ischemia. Patients with mental stress ischemia more often had daily life ischemia than patients without mental stress ischemia, but their exercise tests were similar. Patients with daily life ischemia had higher ejection fraction and cardiac output, and lower systemic vascular resistance during mental stress than patients without daily life ischemia. Blood pressure and catecholamine levels at rest and during the mental stress tests were not different in patients with, compared with those without, daily life ischemia. Patients with daily life ischemia had a higher ejection fraction at rest and at peak bicycle exercise compared with patients without daily life ischemia, but there were no other differences in peak hemodynamic or catecholamine responses to exercise. The presence of ST segment depression during routine daily activities was best predicted by ST segment depression during mental or bicycle exercise stress, although ST segment depression was rare during mental stress.

CONCLUSIONS

Patients with daily life ischemia exhibit a heightened generalized response to mental stress. ST segment depression in response to mental or exercise stress is more predictive of ST segment depression during routine daily activities than other laboratory-based ischemic markers. Therapeutic management strategies might therefore focus on patients with these physiologic responses to stress and on whether lessening such responses reduces ischemia.

The Women's Ischemia Syndrome Evaluation (WISE) study: protocol design, methodology and feasibility report

OBJECTIVES

The Women's Ischemia Syndrome Evaluation (WISE) is a National Heart, Lung and Blood Institute-sponsored, four-center study designed to: 1) optimize symptom evaluation and diagnostic testing for ischemic heart disease; 2) explore mechanisms for symptoms and myocardial ischemia in the absence of epicardial coronary artery stenoses, and 3) evaluate the influence of reproductive hormones on symptoms and diagnostic test response.

BACKGROUND

Accurate diagnosis of ischemic heart disease in women is a major challenge to physicians, and the role reproductive hormones play in this diagnostic uncertainty is unexplored. Moreover, the significance and pathophysiology of ischemia in the absence of significant epicardial coronary stenoses is unknown.

METHODS

The WISE common core data include demographic and clinical data, symptom and psychosocial variables, coronary angiographic and ventriculographic data, brachial artery reactivity testing, resting/ambulatory electrocardiographic monitoring and a variety of blood determinations. Site-specific complementary methods include physiologic and functional cardiovascular assessments of myocardial perfusion and metabolism, ventriculography, endothelial vascular function and coronary angiography. Women are followed for at least 1 year to assess clinical events and symptom status.

RESULTS

In Phase I (1996-1997), a pilot phase, 256 women were studied. These data indicate that the WISE protocol is safe and feasible for identifying symptomatic women with and without significant epicardial coronary artery stenoses.

CONCLUSIONS

The WISE study will define contemporary diagnostic testing to evaluate women with suspected ischemic heart disease. Phase II (1997-1999) is ongoing and will study an additional 680 women, for a total WISE enrollment of 936 women. Phase III (2000) will include patient follow-up, data analysis and a National Institutes of Health WISE workshop.

Efficacy and safety of sildenafil citrate in the treatment of erectile dysfunction in patients with ischemic heart disease

Erectile dysfunction is a common condition in men with cardiovascular disease, probably as a result of shared factors that impair hemodynamic mechanisms in the penile and ischemic vasculature. Sildenafil citrate, an orally active, selective inhibitor of phosphodiesterase type 5 (PDE5), has demonstrated excellent efficacy and safety profiles in men with erectile dysfunction of various etiologies. Sildenafil administration is contraindicated in patients who are taking nitrates or nitric oxide donors. This retrospective subanalysis of data from double-blind, placebo-controlled studies assessed the efficacy (9 studies) and safety (11 studies) of sildenafil in patients with erectile dysfunction and ischemic heart disease who were not taking nitrates. Of 3,672 patients randomized to receive sildenafil (5-200 mg) or placebo for 4-24 weeks in 11 double-blind, placebo-controlled studies, 357 (10%) reported a history (past or present) of ischemic heart disease and were not taking nitrates. Efficacy was assessed using end-of-treatment responses to Question 3 (ability to achieve an erection) and Question 4 (ability to maintain an erection) of the International Index of Erectile Function (IIEF), scores for the 5 domains of male sexual function assessed by the IIEF (erectile function, orgasmic function, sexual desire, intercourse satisfaction, and overall satisfaction), and responses to a global efficacy question ("Did the treatment improve your erections?"). The responses to the 2 IIEF questions were graded on a scale of 1 (almost never or never) to 5 (almost always or always), with a score of 0 indicating no attempt at sexual intercourse. At the end of treatment, the mean scores for Question 3 and Question 4 of the IIEF for patients with erectile dysfunction and ischemic heart disease were significantly higher for the sildenafil group than for the placebo group (p <0.0001). Mean end-of-treatment scores for the IIEF domains also demonstrated significant increases for sildenafil-treated patients compared with those receiving placebo (p <0.05). At the end of treatment, improved erections were reported by 70% of patients who received sildenafil and by 20% of those in the placebo group p <0.0001). For the sildenafil group, the incidences of the most common adverse events (headache 25%, flushing 14%, and dyspepsia 12%) for patients with ischemic heart disease were similar to those in patients without this concomitant illness (21%, 15%, and 10%, respectively). Moreover, the overall incidence of cardiovascular adverse events other than flushing was comparable in patients with and without ischemic heart disease for both treatment groups. Since there is a degree of cardiac risk associated with sexual activity, clinicians should consider the patient's cardiovascular status before initiating any treatment for erectile dysfunction. Physicians should be aware that patients with underlying cardiovascular disease could be adversely affected by the vasodilator effects of sildenafil, especially in combination with sexual activity. The results of the present subanalysis indicate that oral sildenafil significantly improves erectile function and is well tolerated in patients with erectile dysfunction and ischemic heart disease who are not taking nitrate therapy.

Factors influencing clinical outcomes after revascularization in the asymptomatic cardiac ischemia pilot (ACIP). ACIP Study Group

BACKGROUND AND AIM

The Asymptomatic Cardiac Ischemia Pilot is the first randomized trial where revascularization involved choice of either coronary bypass or angioplasty used in an early or a delayed symptom-driven approach. One-year outcomes were favorable (reduced recurrent ischemia and adverse outcomes) for an early revascularization strategy (within 4 weeks), compared with an early medical strategy when revascularization was delayed until symptom-driven. This ancillary study examined variables influencing outcomes after these 2 revascularization approaches (early vs. delayed until symptom-driven).

METHODS

Participants were clinically stable coronary disease patients with stress-induced and daily life ischemia who underwent revascularization. Characteristics associated with clinical outcomes occurring within the year following revascularization were examined using Cox regression analysis.

RESULTS

A total of 262 patients received revascularization; 170 in the early approach and 92 in the delayed symptom-driven approach. Thirty-three patients had adverse outcomes (death, nonfatal myocardial infarction, or repeat revascularization) during 1-year follow-up. The most important independent predictor of improved outcome during the follow-up year was attempted revascularization of > or = 66% of vessels with significant stenosis for the early (risk ratio [RR] 0.25, 95% confidence interval [CI] 0.09-0.67) and the delayed (RR 0.21, CI 0.08-0.58) approaches. Factors such as age, stress test results, and coronary angiographic findings did not predict clinical outcome.

CONCLUSIONS

Our findings are important in the planning of a large trial with longer follow-up.

Rationale and design of the International Verapamil SR/Trandolapril Study (INVEST): an Internet-based randomized trial in coronary artery disease patients with hypertension

OBJECTIVES

The primary objective of the International Verapamil SR/Trandolapril Study (INVEST) is to compare the risk for adverse outcomes (all-cause mortality, nonfatal myocardial infarction [MI] or nonfatal stroke) in hypertensive patients with coronary artery disease (CAD) treated with either a calcium antagonist-based or a noncalcium antagonist-based strategy.

BACKGROUND

Treatment recommendations for hypertension include initial therapy with a diuretic or beta-adrenergic blocking agent, for which reductions in morbidity and mortality are documented from randomized trials but are less than expected from epidemiologic data. For this reason, recent attention has focused on calcium antagonists or angiotensin-converting enzyme inhibitors. While these agents reduce blood pressure, outcome data from large randomized trials are lacking, but some case-control data, dominated by short-acting dihydropyridines, suggest an increased risk of cardiovascular events. These studies had methodologic limitations and did not differentiate among calcium antagonist types and formulations. Several studies differentiating among calcium antagonist types and an overview of published randomized trials show no increased risk with verapamil and suggestion for benefit in CAD patients.

METHODS

A total of 27,000 CAD patients with hypertension will be randomized at 1,500 primary care sites to receive either a calcium antagonist-based (verapamil) or beta-blocker/diuretic-based (atenolol/hydrochlorothiazide) antihypertensive care strategy. The study uses a novel, electronic "paper-less" system for direct on-screen data entry, randomization and drug distribution from a mail pharmacy linked to the coordination center via the Internet.

RESULTS

Contract negotiations with the United States and international sites are ongoing. Patients being enrolled are predominantly elderly (72% aged 60 years or older) men (54%), with either an abnormal coronary angiogram or prior MI (71%). In addition to hypertension, CAD and elderly age, most patients (89%) have one or more associated conditions (diabetes, dyslipidemia, smoking, cerebral or peripheral vascular disease, etc.) contributing to increased risk for adverse outcome. While 26% have diabetes, most of these are noninsulin dependent. Using the protocol strategies, target blood pressures (according to JNC VI) have been reached in 58% at the fourth visit, and as expected most (89%) are requiring multiple antihypertensive drugs.

CONCLUSION

The design and baseline characteristics of the initial patients recruited for a prospective, randomized, international, multicenter study comparing two therapeutic strategies to control hypertension in CAD patients are described.

Aspirin and newer orally active antiplatelet agents in the treatment of the post-myocardial infarction patient

The thienopyridine derivatives, ticlopidine and clopidogrel, provide alternatives to aspirin for use in the prevention of recurrent ischemic events in the post-myocardial infarction patient. These drugs act through a different mechanism than aspirin and, as a result, have potentially different profiles of safety and efficacy. The following discusses the clinical data collected supporting the use of these drugs for secondary prevention and the unanswered questions that remain regarding their use in subpopulations of individuals at risk. Based on the available data, it may be concluded that aspirin should remain the drug of choice for the prevention of recurrent ischemic events in the majority of patients who have suffered a recent myocardial infarction.

Angina pectoris in a contemporary population: characteristics and therapeutic implications. TIDES Investigators

We characterized a contemporary, nonhospitalized population with angina pectoris by obtaining data from a geographically diverse cohort of 5125 outpatients with chronic stable angina cared for by 1266 primary-care physicians. Diagnosis was based on history supported by evidence for coronary artery disease (coronary angiography, old myocardial infarction [MI], and/or an abnormal stress test). Their mean age was 69 years and 53% were women. Seventy percent had more than one associated illness, and 65% used more than one cardiovascular drug. Calcium antagonists (46%) and nitrates (61%) were used most frequently. Median angina frequency was approximately 2 episodes/week, and increased angina frequency was associated (P < 0.0001) with decreased overall feeling of well-being. Although effort angina was present in 90% of patients, 47% also had rest angina and 34% had mental stress-evoked angina. Female gender (odds ratio: 1.09; 95% CI: 1.02-1.16), concomitant illness (1.17, 1.09-1.25), and pharmacotherapy (1.14, 1.07-1.22) were associated with rest angina. Younger age (1.30, 1.20-1.41), female gender (1.16, 1.07-1.26), concomitant illness (1.13, 1.03-1.24), and pharmacotherapy (1.28, 1.15-1.93) were associated with mental stress angina. Calcium antagonists were used for rest-evoked (1.09, 1.03-1.16) and mental stress-evoked (1.12, 1.04-1.21) angina. These data suggest that contemporary outpatients with angina are most likely to be women and elderly patients with high frequencies of associated illness, calcium antagonist and nitrate use, as well as rest- and mental stress-related angina. These characteristics differ from previous perceptions.

Systemic hypertension and coronary artery disease

In the United States alone, it is estimated that 60 million people have hypertension, the estimate varying according to whether hypertension is defined as a blood pressure of >140/90 mm Hg or, as has emerged from the Sixth Joint National Commission on Hypertension (JNC VI) consensus conference, of >130/90 mm Hg. Coronary artery disease frequently accompanies hypertension. In our studies of >5,000 patients with coronary artery disease, half had hypertension. The reasons are numerous. Hypertension is a major risk factor for CAD. The incidence of both conditions increases with age, so that the majority of individuals >65 years of age with coronary artery disease probably also have hypertension. Some authorities predict that, due to the increasing size of the elderly population, there will be a doubling in the prevalence of both coronary artery disease and hypertension in the next century. This is of vital concern to all clinicians. This article reviews some of the prevalence and population trends in coronary artery disease and hypertension, and some of the pathogenic mechanisms involved, as well the results of some current outcome trials.

Heterogeneity among cardiac ischemic and anginal responses to exercise, mental stress, and daily life

The objectives of this study were to compare and contrast indicators of ischemia in a well-characterized group of 196 patients with coronary artery disease, documented angiographically or by verified history of myocardial infarction, and a positive exercise test result. Myocardial ischemia occurs frequently in response to everyday stressors in patients with coronary artery disease. The Psychophysiological Interventions in Myocardial Ischemia study provides a unique opportunity to study neuroendocrine and psychological manifestations of ischemia. Patients with exercise-induced ischemia underwent exercise radionuclide ventriculography and electrocardiographic monitoring and 2 laboratory mental stressors (Speech and Stroop) after being withdrawn from cardiac medications. In addition, 48-hour ambulatory electrocardiograms were recorded during routine daily activities. Patients with a history of angina within the past 3 months reported angina during the bicycle or treadmill test with a much higher frequency than patients without such an anginal history (77% vs 26%). Ejection fraction (EF) responses to the Stroop test were abnormal in 48% of patients with an abnormal EF response to the Speech task, versus 17% in patients with a normal EF response (p <0.01). Seventy-six percent of patients had an abnormal EF response to bicycle exercise. Three indicators of ischemia (ST-segment depression, wall motion abnormality, and EF response) were compared during the same laboratory stressor and across different types of stress tests. Presence of the 3 indicators was only moderately associated during exercise, and only weak or nonsignificant associations occurred among the presence of the 3 ischemic markers during mental stress. Occurrence of the same ischemic markers was moderately associated between the 2 mental stress tasks, but few associations were found between the occurrence of the same ischemic marker during exercise and mental stress. There is a marked heterogeneity of responses to psychological and exercise stress testing using electrocardiography, ambulatory electrocardiography, or radionuclide criteria for ischemia during stress. The heterogeneity may be related to differences in the magnitude or types of physiologic responses provoked and to differences in the sensitivity and specificity of the different tests used to identify ischemia.

Rationale for ACE inhibition as an anti-ischaemic therapy

Research has established endothelial dysfunction as a pathophysiological mechanism underlying many cardiovascular disease processes. Tissue angiotensin-converting enzyme (ACE) plays a central role in regulating processes that contribute to endothelial function and cardiovascular disease. A number of large clinical studies have demonstrated conclusively the beneficial effects of ACE inhibition in patients with myocardial ischaemia and left ventricular dysfunction, including a significant reduction in the risk of recurrent myocardial infarction. Mechanistic findings from these studies indicated that the beneficial effects of ACE inhibition would extend to patients with preserved left ventricular function. Available results suggest that ACE inhibition with quinapril improves endothelial function in large and small vessels in patients with coronary artery disease and preserved left ventricular function. Quinapril also inhibits progression of coronary atherosclerosis in patients with high levels of low-density lipoprotein cholesterol (> or = 130 mg.dl-1) and reverses the toxic effects of smoking on endothelial function. Endothelial dysfunction also may be an important mechanism in episodes of angina and silent ischaemia. The central role of tissue ACE in endothelial function suggests that ACE inhibition has antiischaemic effects. A study in progress, the QUinapril Antiischaemia and Symptoms of Angina Reduction trial, addresses shortcomings in earlier studies of ACE inhibition for ischaemia and is expected to define the role of quinapril in ischaemia.