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[The authors respond:]
In our review, in particular in the section on loop diuretics, we attempted to outline many of the controversies associated with the treatment of volume overload in acute decompensated heart failure.1 We provided 3 references to support the statement that use of loop diuretics in the acute setting is associated with increased mortality. We highlighted the potentially detrimental vasoconstrictive properties of furosemide. We also recognized the importance of alternative approaches, including therapy with vasodilators and positive airway pressure.
Joe Nemeth is correct that elevation of pulmonary capillary wedge pressure (“congestion”) is not necessarily equivalent to volume overload. However, it is our understanding that the vast majority of patients in this situation do have total body volume overload, as evidenced by edema, increased venous filling pressures and hemodilution.2–5 From our clinical experience we would argue for some form of volume reduction therapy as part of the overall treatment strategy for most patients presenting with worsened heart failure and signs of congestion. Few clinicians would dispute that removing fluid from such patients makes them feel better. To further study these issues, we are participating in the development of a randomized trial sponsored by the National Institutes of Health Heart Failure Network in which low and high doses of furosemide will be compared in the treatment of acute decompensated heart failure.
The dose conversions for sublingual to intravenous nitroglycerin provided by Howard Smithline are very helpful. Patients with marked hypertension who tolerate sublingual nitroglycerin may certainly be started at relatively higher doses than we recommended in our article. However, the effect of a single dose of sublingual nitroglycerin is typically short-lived, so direct comparison with a continuous infusion of nitroglycerin may not be appropriate. Hypotension is problematic in the management of such patients and consequently we use a conservative approach, starting with a relatively low dose of intravenous nitroglycerin that is then titrated upward rapidly as tolerated by the patient, as evidenced by hemodynamic measurements and symptoms.
Footnotes
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Competing interests: None declared for Dr. Allen. Dr. O'Connor has acted as a consultant to and has received speaker fees from Pfizer, GlaxoSmithKline, Medtronic and NitroMed.