The mechanical function of the heart is known to deteriorate with increasing age and disease. After rigorous screening of necropsied hearts to exclude cardiovascular disease, Olivetti et al¹ in New York showed that about one third of the cardiomyocytes are lost from the human male heart between the ages of 17–90 years. This natural attrition contrasts with the loss incurred through myocardial infarction and cardiomyopathy, the most common causes of heart failure (HF) in western societies. We sought to identify whether the functional impacts of cardiac impairment through aging and HF are similar or different by conducting symptom limited cardiopulmonary exercise testing in conjunction with haemodynamic evaluations.

METHODS

Thirty seven male subjects were recruited and assigned to the following groups. The first group (20y-Sed) consisted of sedentary untrained healthy men aged 21 (1.6) years (mean (SD), n  =  12). The second group (60y-Sed) were 60 (2.9) years old (n  =  14). They were screened by a medical history-lifestyle questionnaire and a treadmill ECG exercise stress test and considered to be free of overt cardiovascular disease. Subjects with any history of hypertension, diabetes, neuromuscular impairment, or cardiac or other medical conditions, or who were taking prescribed medications known to affect cardiovascular or respiratory function were excluded. The third group (60y-HF) consisted of 58.3 (3.2) year old patients with HF (n  =  11). These patients were in New York Heart Association class III with impaired left ventricular systolic function and consisted of men with congestive HF secondary to idiopathic dilated cardiomyopathy and ischaemic heart disease, who were undergoing clinically indicated cardiopulmonary exercise testing with a view to estimating prognosis and …