Christian Werner, MD, Klinik für Innere Medizin III, Kardiologie, Angiologie und Internistische Intensivmedizin, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany.
Michael Böhm, MD, Klinik für Innere Medizin III, Kardiologie, Angiologie und Internistische Intensivmedizin, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany.

Cardiovascular disease represents a continuum that starts with risk factors such as hypertension and progresses to atherosclerosis, target organ damage, and ultimately to heart failure or stroke. Renin-angiotensin system (RAS) blockade with angiotensin converting enzyme (ACE) inhibitors or angiotensin II type 1 receptor blockers (ARBs) has turned out to be beneficial at all stages of this continuum. Several mechanisms govern the progression of myocardial damage to end-stage chronic heart failure (CHF). Chronic neuroendocrine activation, comprising the RAS, sympathetic nervous system and the release of cytokines, leads to remodelling processes and via forward / backward failure to clinical symptoms of CHF. Therefore, combined RAS inhibition is especially effective to improve neuroendocrine blockade in CHF patients with repetitive cardiac decompensations.
Key words: angiotensin converting enzyme inhibitors, angiotensin receptor blockers, renin-angiotensin system, chronic heart failure, clinical trials.

The accredited CME learning activity based on this article is offered under the auspices of the CE department of the University of Toronto. Participating physicians are entitled to one (1) MAINPRO-M1 credit by completing this program, found online at www.geriatricsandaging.ca/cme.htm

Yves Lacourcière, MD, FRCP, Hypertension Research Unit, CHUL du CHUQ, Laval University, QC.

There are many reasons why gaining control over high blood pressure (BP) in older patients is desirable. When choosing an antihypertensive agent for older patients, physicians should seek a drug that sustains BP control, especially in the last six hours of the dosing interval or if a dose is missed. Agents with a long duration of action that inhibit the renin-angiotensin system (RAS) are likely to be more useful in controlling the early-morning surges in norepinephrine that have been linked to target organ damage and stroke, particularly in older patients.

Key words: hypertension, renin-angiotensin, angiotensin-receptor blockers, norepinephrine, peroxisome proliferator-activated receptor (PPAR).

Robert E. Hobbs, MD, The Kaufman Center for Heart Failure, Department of
Cardiology, Cleveland Clinic Foundation, Cleveland, OH, USA.

Guidelines for managing heart failure recommend angiotension-converting enzyme (ACE) inhibitors, beta-blockers, diuretics, digoxin, and aldosterone antagonists as standard therapy in order to improve morbidity and mortality. Angiotensin receptor blockers (ARBs) are considered second-line agents for patients who are intolerant of ACE inhibitors due to cough or angioedema. Because ACE inhibitors do not completely block the formation of angiotensin II and aldosterone, add-on therapy with an ARB has been evaluated in several clinical trials. In general, the results were mixed. Combination therapy with an ACE inhibitor and an ARB may improve morbidity and probably mortality, but with an increased incidence of hypotension, hyperkalemia, and azotemia. This approach could be considered in patients who remain symptomatic despite optimal doses of standard agents.

Key words: angiotensin receptor blockers, ACE inhibitors, heart failure, vasodilators, hyperkalemia.

Wilbert S. Aronow, MD, Divisions of Cardiology and Geriatrics, New York Medical College, Valhalla, NY, USA.

The American College of Cardiology/American Heart Association guidelines recommend that patients with asymptomatic left ventricular systolic dysfunction or with congestive heart failure (CHF) be treated with angiotensin-converting enzyme (ACE) inhibitors plus beta-blockers unless there are contraindications to the use of these drugs. Beta-blockers have been demonstrated to significantly reduce all-cause mortality associated with abnormal or normal left ventricular ejection fraction in older and younger patients with CHF. An angiotensin receptor blocker should not be administered to patients with CHF who are being treated with a beta-blocker plus ACE inhibitor, but should be given to patients with CHF treated with beta-blockers who cannot tolerate ACE inhibitors due to cough, angioneurotic edema, rash or altered taste sensation.
Key words: congestive heart failure, left ventricular ejection fraction, beta-blockers, angiotensin-converting enzyme inhibitors, angiotensin receptors blockers.

J. George Fodor, MD, PhD, FRCPC, FAHA, Professor of Medicine, Head of Research, University of Ottawa Heart Institute Prevention and Rehabilitation Centre, Ottawa, ON.

It is worthwhile to review the issue of hypertension in the elderly not only because it will become an ever-increasing problem with our aging population, but also because of the robust database currently at our disposal concerning improved risk assessment and efficacious therapy.

The Epidemiology
Generally, the elderly are considered those above 65 years of age. Dealing with hypertension in this age group, we quickly realize that this disease is a major epidemic with far-reaching consequences for both the health status of this segment of the population as well as our health care system.

The Canadian Heart Health Survey ascertained that among people in the age group 65-74 years, 56% of males and 58% of females were hypertensive.¹ This survey defined hypertension as systolic blood pressure (SBP) > 140mmHg or diastolic blood pressure (DBP) > 90mmHg, or current treatment with a prescription antihypertension medication or non-pharmacological treatment of blood pressure (weight control or sodium/salt restriction). The problem of hypertension in the elderly will continue to increase steadily in importance.

D'Arcy Little, MD, CCFP, Academic Fellow, Department of Family and Community Medicine, University of Toronto, and Director of Medical Education, York Community Services, Toronto, ON.

Introduction
Congestive heart failure (CHF) is a serious common, condition. It qualifies as one of the most important contributors to cardiovascular morbidity and mortality in the developed world. Due to the burgeoning elderly population, as well as to new treatments for acute myocardial infarction which are allowing more patients to survive with impaired ventricular function, the incidence of CHF will continue to increase dramatically.¹ While significant improvements in CHF therapy have been made in the last few decades with the development of angiotensin-converting enzyme inhibitors (ACE inhibitors), as well as a clarification of the role of beta-blockers in therapy, additional strategies are still needed to further reduce progression of disease and consequent morbidity and mortality.^1,2 Angiotensin receptor blockers (ARB) may represent an additional approach to the treatment of CHF with the possibility for improved outcomes. Despite physiological explanations that would make such an assertion sound, significant supporting clinical data are currently lacking.