Ventricular ectopy during prolonged ambulatory electrocardiographic monitoring in elderly hypertensive subjects.

To examine whether ventricular ectopy in hypertensive older people is associated with age, the hypertensive process, or treatment, a 24-hour ambulatory electrocardiogram recording was obtained in 94 noninstitutionalized subjects aged 60-90 years with isolated hypertension and 136 noninstitutionalized normotensive subjects aged 60-82 years. A significantly higher prevalence of frequent ventricular ectopic beats (VEB greater than 100 per recording) was found in hypertensive and normotensive groups age greater than or equal to 70 years compared to age 60-69 years (44% vs 15%, P less than .01, and 28% vs 9%, P less than 01, respectively). Complex ventricular ectopy was found to be significantly increased only in the hypertensive group greater than or equal to 70 years compared to 60-69 years (53% vs 28%, P less than .05). No significant difference for any type of ventricular ectopy was found between treated and untreated hypertensive subjects. Analysis of variance of frequent ventricular ectopy showed a significant effect of age (P less than .001) but not of hypertension. Multivariate regression analysis with frequent ventricular ectopy as the dependent variable confirmed this relationship. For complex ventricular ectopy, analysis of variance showed a significant effect of hypertension (P less than .001) and age (P less than .05). Multivariate regression analysis confirmed that complex ventricular ectopy was significantly associated with hypertension (P less than .01) and age (P less than .05). In elderly subjects aging alone is associated with increased frequency of ventricular ectopy, whereas complex ventricular ectopy is more significantly related to the hypertensive process than to age.

Intermittent claudication. The effect of physical training on walking tolerance and venous lactate concentration.

Twenty-one patients with intermittent claudication underwent a physical exercise program lasting 8 weeks. The patients were classified on the basis of maximal walking tolerance (MWT) and diagnosis at the initial examination. Seven of the patients had a MWT less than 1,000 m and no symptoms of chronic obstructive airways disease (COAD) or angina (group A), seven had a MWT less than 1,000 m plus angina and/or COAD (group B) and seven had an unlimited (greater than 1,250 m) MWT (group C). At the completion of the training program all three groups showed a significant improvement in walking distance to pain and stress test capacity. During the post-training walking tolerance test, the venous lactate concentrations in group A were lower after 2 min and 4 min of exercise, and at exhaustion (P less than 0.05). Group A patients showed a significant correlation between an increase in MWT after training and a decrease in maximum lactate concentration measured during walking. Although the patients in group B had a significant increase in MWT, blood lactate concentrations in this group were not always decreased by physical training. Group C lactate concentrations were lower after 8 min, 15 min, and 30 min of walking (P less than 0.05). It is concluded that a physical training program increases walking tolerance in different categories of claudicants, and possible mechanisms for the improvement are discussed.