I recently read the meta-analysis on the use of b-blockers to treat systolic dysfunction by Lee and Spencer.1 Although I agree that b-blockers may provide very useful therapy for many patients with heart failure, I have a few comments. The text described systolic dysfunction as patients with an ejection fraction of less than 40%. That is actually a bit low; the cutoff is generally 45% and sometimes even 50%. Also, in the conclusion it is stated that all patients with New York Heart Association classes II and III heart failure should be placed on b-blocker therapy. It seems that in this conclusion patients with both systolic and diastolic dysfunction are included, though the article only discusses patients with systolic dysfunction. Perhaps the authors can clarify which patients were meant.
Sarah Pressman Lovinger, MD
Boston University Medical Center
Massachusetts
- Lee S, Spencer A. Beta-blockers to reduce mortality in patients with systolic dysfunction: a meta-analysis. J Fam Pract 2001; 50:499-504.
Drs Lee and Spencer responded as follows:
We appreciate the opportunity to respond to Dr Lovinger’s thoughtful comments regarding our research. With reference to the first comment, we recognize that systolic heart failure may be defined using an ejection fraction below that which is generally recognized as normal. However, noted treatment guidelines and consensus recommendations refer to systolic heart failure as a left ventricular ejection fraction less than or equal to 40%.1,2 The articles included in our analysis evaluated patients with a maximum ejection fraction ranging from 35% to 45%. Of course, the diagnosis of heart failure and treatment decisions should be made on the basis of both objective and subjective signs and symptoms. Of note, practitioners may only have readily available an estimate of a patient’s ejection fraction, rather than a precise measure. The New York Heart Association (NYHA) functional classification provides an additional means of assessing heart failure severity to guide treatment and monitor patient response.
With regard to our conclusion that patients with NYHA classes II and III heart failure should receive b-blocker therapy, it was not our intention to extrapolate this to patients with diastolic dysfunction. As noted in the title and introduction, the goal of the research was to synthesize available data and determine whether b-blocker therapy reduces the risk of mortality in patients with systolic dysfunction. To that end, only trials including patients with a diagnosis of systolic heart failure were included in the analysis. We hope that these clarifications assist other practitioners in drawing appropriate conclusions from our analysis.
Susanne Lee, PharmD
Anne P. Spencer, PharmD, BCPS
Medical University of South Carolina
- Packer M, Cohn JN, eds. Consensus recommendations for the management of chronic heart failure. Am J Cardiol 1999; 83:1A-38A.
- Heart Failure Society of America. HFSA guidelines for management of patients with heart failure cause by left ventricular systolic dysfunction—pharmacological approaches. J Card Fail 1999; 5:358-82.