Toleration of high doses of angiotensin-converting enzyme inhibitors in patients with chronic heart failure - Results from the ATLAS trial

Background: Treatment wi th angiotensin-converting enzyme (ACE) inhibitors reduces mortality and morbidity in patients with chronic heart failure (CHF), but most affected patients are not receiving these agents or are being treated with doses lower than those found to be efficacious in trials, primarily because of concerns about the safety and tolerability of these agents, especially at the recommended doses. The present study examines the safety and tolerability of high-compared with low-dose lisinopril in CHF. Methods: The Assessment of Lisinopril and Survival study was a multicenter, randomized, double-blind trial in which patients with or without previous ACE inhibitor treatment were stabilized receiving medium-dose lisinopril (12.5 or 15.0 mg once daily [OD]) for 2 to 4 weeks and then randomized to high- (35.0 or 32.5 mg OD) or low-dose (5.0 or 2.5 mg OD) groups. Patients with New York Heart Association classes II to IV CHF and left ventricular ejection fractions of no greater than 0.30 (n=3164) were randomized and followed up for a median of 46 months. We examined the occurrence of adverse events and the need for discontinuation and dose reduction during treatment, with a focus on hypotension and renal dysfunction. Results: Of 405 patients not previously receiving an ACE inhibitor, doses in only 4.2% could not be titrated to the medium doses required for randomization because of symptoms possibly related to hypotension (2.0%) or because of renal dysfunction or hyperkalemia (2.3%). Doses in more than 90%; of randomized patients in the high- and low-dose groups were titrated to their assigned target, and the mean doses of blinded medication in both groups remained similar throughout the study. Withdrawals occurred in 27.1% of the high- and 30.7% of the low-dose groups. Subgroups presumed to be at higher risk for ACE inhibitor intolerance (blood pressure, <120 mm Hg; creatinine, <greater than or equal to>132.6 mu mol/L [greater than or equal to1.5 mg/dL]; age, greater than or equal to 70 years; and patients with diabetes) generally tolerated the high-dose strategy. Conclusions: These findings demonstrate that ACE inhibitor therapy in most patients with CHF can be successfully titrated to and maintained at high doses, and that more aggressive use of these agents is warranted.