So many definitions of heart failure: are they all universally valid? A critical appraisal.

Cardiology Department, Leeds General Infirmary, Leeds LS1 3EX, UK.
Expert Review of Cardiovascular Therapy 02/2010; 8(2):217-28. DOI: 10.1586/erc.09.187
Source: PubMed

ABSTRACT Defining heart failure (HF) is a matter of finding the most appropriate words to formulate the definiens for HF that will be universally applicable in all specific circumstances pertaining to the nature of HF. Currently available definitions of HF contain ambiguities and notable deficiencies such that non-heart failure medical conditions can become mislabelled as heart failure. Principles of how best to formulate definitions have been employed to provide a guide on how to appraise published definitions of HF. A fundamental requirement of a good definition is that it should be universal, and by this criterion, we need to question the validity of a conventional dogma that a collection of clinical diagnostic features are equivalent to HF definitions. A long-standing deficiency in HF definitions is the inability to take into account the quantifiable extent of functional impairment of the heart. Other traditional misconceptions surrounding HF definitions have also been addressed. In line with Derek Gibson's proposal, we have rephrased William Harvey's description of the cardiac role in maintaining the circulation in terms of Newtonian physics and of the Law of Conservation of Energy to reach a more universal and less ambiguous definition of HF, with the objective of advancing the science of HF and the treatment of this distressing condition.

  • International journal of cardiology 05/2013; · 6.18 Impact Factor
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    ABSTRACT: Although all aspects of clinical work nowadays are modified by the pervading influence of evidence-based medicine (EBM) and multiplicative guidelines, not many clinicians realize that the underlying premise of EBM-driven guidelines is a particular strain of consequentialist ideology. Subservience to this ideology has transformed modern medical practice, but there is a real risk of distorting good medical practice, of belittling clinical judgement, of disempowering clinicians, and subjecting patients to skewed medical reality and treatment options. With so many heart failure (HF) guidelines issued by various august bodies, it is therefore timely to reappraise principles governing modern HF therapy with a fresh examination of the hierarchy of medical imperatives, the role of alternatives to consequentialism including deontological principles in HF therapy. In addition, other ideology worth re-examining, aside from EBM, are the principle of appropriate definition of HF underlying therapeutic goals and the principle of prioritizing objectives of HF therapy. Even within standard EBM, there are many questions to reconsider: about what types of evidence are admissible, different interpretations of available evidence, emphasizing patient-centered outcome measures instead of randomized controlled trials quantifiable therapeutic outcomes, how to prescribe drugs for prognostic versus symptomatic benefits, and how to deliver HF therapy based on pathophysiological features through mechanistic considerations and not just confined to randomized controlled trials or meta-analytical statistical imperatives. Through re-examination of these fundamental principles of HF therapy, it is hoped that clinicians will be empowered to manage HF patients more holistically and better deliver HF therapies in the best interest of each individual patient.
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