Heart failure angiotensin receptor blockers

FIGURE 3-1. Treatment algorithm for chronic heart failure. ACE, angiotensin-converting enzyme ARB, angiotensin receptor blocker EF, ejection fraction HF, heart failure LV, left ventricular Ml, myocardial infarction SOB shortness of breath. Table 3-5 describes staging of heart failure. 

Many patients cannot tolerate chronic ACE inhibitor therapy secondary to adverse effects outlined below. Alternatively, the angiotensin receptor blockers (ARBs), can-desartan and valsartan, have been documented in trials to improve clinical outcomes in patients with heart failure.68,69 Therefore, either an ACE inhibitor or candesartan or valsartan are acceptable choices for chronic therapy for patients who have a low ejection fraction (EF) and heart failure following MI. Since more than five different ACE inhibitors have proven benefits in MI while only two ARBs have been studied, the benefits of ACE inhibitors are generally considered a... 

An angiotensin receptor blocker may be prescribed for patients with ACE inhibitor cough and a low LVEF and heart failure after MI. Example doses include the following ... 

Mangoni AA, Jackson SH. The implications of a growing evidence base for drug use in elderly patients Part 2. ACE inhibitors and angiotensin receptor blockers in heart failure and high cardiovascular risk patients. Br J Clin Pharmacol 2006 61(5) 502-12. 

Cohn J et al A randomized trial of the angiotensin receptor blocker valsartan in heart failure. N Engl J Med 2002 345 1667. 

Jong P et al Angiotensin receptor blockers in heart failure Meta-analysis of randomized controlled trials. J Am Coll Cardiol 2002 39 463. 

Erhardt LR. A review of the current evidence for the use of angiotensin-receptor blockers in chronic heart failure. IntJ Clin Pract. 2005 59 571-578. 

Cohn JN, Tognoni G, Glazer RD, Spormann D, Hester A. Rationale and design of the Valsartan Heart Failure Trial a large multinational trial to assess the effects of valsartan, an angiotensin-receptor blocker, on morbidity and mortality m chronic congestive heart failure. J Card Fail 1999 5(2) 155-60. 

Besides hypotension, the most frequent adverse reaction to an ACE inhibitor is cough, which may occur in up to 30% of patients. Patients with ACE inhibitor cough and either clinical signs of heart failure or LVEE less than 40% may be prescribed an angiotensin-receptor blocker (ARB). Both candesartan and valsartan have improved outcomes in clinical trials in patients with heart failure. Other less common but more serious adverse effects of ACE inhibitors include acute renal failure, hyperkalemia, and angioedema. Although some data have suggested that aspirin use may decrease the benefits from ACE inhibitor treatment, a systematic review of more than 20,000 patients demonstrated that ACE inhibitors improve outcome irrespective of treatment with aspirin. ... 

Another class of vasoactive agents with demonstrated benefit in secondary MI prevention are the angiotensin-con-verting enzyme (ACE) inhibitors. Several large trials of angiotensin receptor blockers as secondary prevention agents are now also underway. Most of the evidence for benefit from ACE inhibitors has centered on patients with heart failure (59). An exception to this was the Heart Outcomes Prevention Evaluation (HOPE) trial, which excluded patients with ejection fractions <40%, and involved 9297 patients (60). There was a 25% reduction in cardiac mortality in patients receiving the ACE inhibitor ramipril. 

Anand IS, Bishu K, Rector TS, Ishani A, Kuskowski A, Cohn JN. Proteinuria, chronic kidney disease, and the effect of an angiotensin receptor blocker in addition to an angiotensin-converting enzyme inhibitor in patients with moderate to severe heart failure. Circulation 2009 120 1577-84. 

Medications can increase the risk of hyperkalemia in patients with CKD, including angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers, used for the treatment of proteinuria and hypertension. Potassium-sparing diuretics, used for the treatment of edema and chronic heart failure, can also exacerbate the development of hyperkalemia, and should be used with caution in patients with stage 3 CKD or higher. 

Paradoxically, these agents—not positive inotropic drugs—are the first-line therapies for chronic heart failure. The drugs most commonly used are diuretics, ACE inhibitors, angiotensin receptor antagonists, aldosterone antagonists, and blockers (Table 13-1). In acute failure,... 

Angiotensin ll-receptor blockers are not currently approved for treating heart failure they are used primarily as an alternative if patients cannot tolerate ACE inhibitors. 

Consequendy, ARBs are used primarily as an alternative for people who are unable to tolerate traditional ACE inhibitors.17,46,47 Future studies comparing ACE inhibitors with these newer angiotensin II receptor blockers should help clarify which type of drug—or perhaps a combination of the two—provides optimal treatment in heart failure.17... 

Angiotensin ATi receptor-blockers such as losartan (see Chapter 11 Antihypertensive Agents and Chapter 17 Vasoactive Peptides) appear to have similar but more limited beneficial effects, and clinical trials of these drugs in heart failure continue. 

Iwata, A., Miura, S., Nishikawa, H., Kawamura, A., Matsuo, Y., Sako, H., Kumagai, K., Matsuo, K., and Saku, K. 2006. Significance of combined angiotensin II receptor blocker and carvedilol therapy in patients with congestive heart failure and arginine variant. J. Cardiol. 47 1-7. 

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