Influence of aging on pulmonary hemodynamics in a population free of coronary artery disease

Previous studies showing an increase in pulmonary artery (PA) pressures and vascular resistance with aging have not systematically excluded subjects with coronary artery disease or left ventricular systolic dysfunction. To better determine the influence of aging on PA hemodynamics in the absence of disease, we identified 47 normal subjects anglographically free of coronary artery disease (18 men, 29 women) with normal left ventricular systolic function (ejection fraction ≥50% and left ventricular end-diastolic pressure <14 mm Hg) from 5,508 consecutive patients undergoing cardiac catheterlzation and coronary angiography between September 10, 1982 and March 9, 1987. AN subjects met a set of clinical and laboratory criteria identifying them as normal. In group I (age ≥60 years) mean PA pressure was 16 ± 3 mm Hg, pulmonary vascular resistance was 124 ± 32 dynes s cm^-5 and the pulmonary/systemic vascular resistance ratio was 0.099 ± 0.046. In contrast, in group II (age <60 years), these values were lower at 12 ± 2 mm Hg, 70 ± 25 dynes s cm^-5 and 0.057 ± 0.019, respectively (all p values <0.01 to 0.001). AN these parameters increased linearly with age (r = 0.69, p <0.001 for pulmonary vascular resistance). The differences were not attributable to body surface area or gender. There was no difference in cardiac output, PA wedge pressure, aortic pressure or systemic vascular resistance between the 2 groups. Thus, PA pressure and vascular resistance increase with aging, a change not attributable to coronary disease or left ventricular systolic dysfunction.