Heart failure (HF) affects more than 5 million people and has an increasing incidence and cost burden. Patients note symptoms of dyspnea and fatigue that result in a decreased quality of life, which has not drastically improved over the past decades despite advances in therapies. The assessment of exercise capacity can provide information regarding patient diagnosis and prognosis, while doubling as a potential future therapy. Clinically, there is acceptance that exercise is safe in HF and can have a positive impact on morbidity and quality of life, although evidence for improvement in mortality is still lacking. Specific prescriptions for exercise training have not been developed because many variables and confounding factors have prevented research trials from demonstrating an ideal regimen. Physicians are becoming more aware of the indices and goals for HF patients in exercise testing and therapy to provide comprehensive cardiac care. It is further postulated that a combination of exercise training and pharmacologic therapy may eventually provide the most benefits to those suffering from HF.
Heart failure, exercise, oxygen uptake, peak oxygen uptake, exercise intensity, quality of life, prevention
The authors have no conflicts of interest to declare.
US Cardiology, 2012;9(1):57-60
Gina G Mentzer, MD, 200 Davis HLRI, 473 W 12th Ave, Columbus, OH 43210. E: firstname.lastname@example.org
Heart failure (HF) affects more than 5 million people, representing 2 % of the population.1,2 At 40 years of age, the lifetime risk of developing HF, regardless of gender, is one in five, with an incidence of 10 per 1,000 population after the age of 65 years.1,3 Despite efforts focused toward primary prevention of HF in the areas of hypertension (HTN), diabetes, obesity, use of cardiotoxic chemotherapies, and ischemic coronary artery disease (CAD), there continues to be an increasing incidence. Seventy-five percent of HF patients have antecedent HTN, and a sedentary lifestyle furthermore places them at high risk of developing HF.1 This disease is of major economic significance, with an estimated cost of $34.8 billion in direct and indirect health-related care in the US in 2008.4 The majority of this economic burden is related to hospitalizations and readmissions: a third of patients are readmitted within 90 days and the number of hospitalizations has tripled from 1,274,000 in 1979 to 3,860,000 in 2004.1,3 From a patient’s perspective, HF remains fairly unrecognized as a deadly disease, although it has a mortality rate that prevails over that of many cancers, reaching 50 % within five years from the time of first diagnosis.1,5
Regardless of the etiology of HF, congestive features, dyspnea and fatigue are the leading limiting symptoms that determine prognosis, quality of life, and use of tailored therapies.6 These symptoms limit exercise and may progress to pulmonary congestion and peripheral edema, creating a continual cycle of decompensation and hospitalization. If these symptoms could be quantified and placed in context, patients would not need to seek as much inpatient medical care and would be able to enjoy an overall better quality of life. Exercise capacity is one parameter with potential to be used in diagnosis, prognosis, and therapeutic measurements of chronic HF, and also as a therapy with the intent of improving symptoms.
Exercise Capacity in Diagnosis and Prognosis
In routine clinical care, physicians address blood pressure and lipid targets, nutrition, exercise, and obesity with patients as part of the primary prevention of cardiovascular (CV) disease. However, more emphasis needs to be placed on physicians identifying those at risk of HF who require intensified primary prevention practices and advanced therapies to prevent progression. In addition, this would need to include an assessment of exercise capacity, with each patient given a specific exercise prescription.7