Objective: To compare survival and outcome in patients receiving a mechanical or bioprosthetic heart valve prosthesis. Design: Randomised prospective trial. Setting: Tertiary cardiac centre. Patients: Between 1975 and 1979, patients were randomised to receive either a Bjork-Shiley or a porcine prostheses. The mitral valve was replaced in 261 patients, the aortic in 211, and both valves in 61 patients. Follow up now averages 20 years. Main outcome measures: Death, reoperation, bleeding, embolism, and endocarditis. Results: After 20 years there was no difference in survival (Bjork-Shiley v porcine prosthesis (mean (SEM)): 25.0 (2.7)% v 22.6 (2.7)%, log rank test p = 0.39). Reoperation for valve failure was undertaken in 91 patients with porcine prostheses and in 22 with Bjork-Shiley prostheses. An analysis combining death and reoperation as end points confirmed that Bjork-Shiley patients had improved survival with the original prosthesis intact (23.5 (2.6)% v 6.7 (1.6)%, log rank test p < 0.0001); this difference became apparent after 8-10 years in patients undergoing mitral valve replacement, and after 12-14 years in those undergoing aortic valve replacement. Major bleeding was more common in Bjork-Shiley patients (40.7 (5.4)% v 27.9 (8.4)% after 20 years, p = 0.008), but there was no significant difference in major embolism or endocarditis. Conclusions: Survival with an intact valve is better among patients with the Bjork-Shiley spherical tilting disc prosthesis than with a porcine prosthesis but there is an attendant increased risk of bleeding.

Maximal O(2) consumption (Vo(2 max)) is lower in individuals with Type 2 diabetes than in sedentary nondiabetic individuals. This study aimed to determine whether the lower Vo(2 max) in diabetic patients was due to a reduction in maximal cardiac output (Q(max)) and/or peripheral O(2) extraction. After 11 Type 2 diabetic patients and 12 nondiabetic subjects, matched for age and body composition, who had not exercised for 2 yr, performed a bicycle ergometer exercise test to determine Vo(2 max), submaximal cardiac output, Q(max), and arterial-mixed venous O(2) (a-v O(2)) difference were assessed. Maximal workload, Vo(2 max), and maximal a-v O(2) difference were lower in Type 2 diabetic patients (P < 0.05). Q(max) was low in both groups but not significantly different: 11.2 and 10.0 l/min for controls and diabetic patients, respectively (P > 0.05). Submaximal O(2) uptake and heart rate were lower at several workloads in diabetic patients; respiratory exchange ratio was similar between groups at all workloads. Vo(2 max) was linearly correlated with a-v O(2) difference, but not Q(max) in diabetic patients. These data suggest that a reduction in maximal a-v O(2) difference contributes to a decreased Vo(2 max) in Type 2 diabetic patients.

Although age-related impairment of diastolic function is well documented, patterns of regional tissue relaxation impairment with age have not been characterized. MRI tissue tagging with a regional three-dimensional (3-D) analysis was performed in 15 younger (age 19-26 yr) and 16 older (age 60-74 yr) normal, healthy volunteers. The peak rate of relaxation of circumferential strain (RC) was decreased in the older group (on average, 105 +/- 28 vs. 163 +/- 18 %/s for older vs. younger, mean +/- SD, P < 0.001) to a greater extent in the lateral wall than in the septum (P = 0.016) and to a greater extent in the apex than in the base (P < 0.001). Peak rate of relaxation of longitudinal strain (RL) was also reduced with age (94 +/- 27 vs. 155 +/- 18 %/s, P < 0.001) to a greater extent in the apex than in the base (P < 0.001). Both RC and RL were greater in the apex than in the base only in the younger subjects (P < 0.001 for each). Peak rate of torsion reversal (RT) was reduced with age (74 +/- 16 vs. 91 +/- 15 degrees/s, P = 0.006) to a greater extent in the base than in the apex (P = 0.035). An increase in regional asynchrony in time to RC and time to RL (P < 0.001 for each), but not time to RT, occurred with age. Thus patterns of regional nonuniformity of myocardial relaxation are altered in a consistent fashion with aging.

The aging process is a major factor that contributes to changes seen in the cardiovascular system in older people. Stiffening of the arterial tree alters afterload and left ventricular geometry and although resting left ventricular systolic function is maintained, left ventricular diastolic function changes substantially. Cardiovascular function in older people during exercise is also significantly altered but can be modified by exercise training in older adults or genetic modification in animals. Age-related changes in cardiovascular structure and function also lower the threshold at which cardiac diseases become apparent. This review describes the changes in cardiovascular structure and function at rest and during exercise in older people and highlights their consequences.

Tagged MRI is a unique, noninvasive imaging method that can identify significant prolongation and reduction of myocardial relaxation in older compared with young normal individuals.

No abstract

Both LVM and LVEDD are predicted by FFM in endurance athletes, and when indexed to FFM, no training-related differences were observed. Thus, the extent of LV remodeling (athletic heart) in trained individuals may reflect a normal physiologic response to increased FFM induced by training.

Left ventricular diastolic filling and systolic function of young and older trained and untrained men. J Appl Physiol 95: 2570-2575. First published July 25, 2003 10.1152/japplphysiol.00441.2003.-Aging is associated with impaired early diastolic filling; however, the effect of endurance training on resting diastolic function in older subjects is unclear. Heart rate and ventricular loading conditions affect mitral inflow velocities measured by Doppler echocardiography; therefore, tissue Doppler imaging of mitral annular velocity, which is relatively preload independent, was combined with mitral inflow velocity and maximal oxygen consumption (V O2 max) in young (20-35 yr) and older (60-80 yr) trained and untrained men to determine whether endurance training is associated with an attenuation of age-associated changes in diastolic filling. As expected, V O2 max was higher in trained men (P Ͻ 0.01) and lower in older men (P Ͻ 0.01). Peak early mitral inflow velocity (E) and early-to-late mitral inflow velocity ratios were lower in older vs. young men (P Ͻ 0.01); however, there was no training effect (P Ͼ 0.05). Peak early mitral annular velocity (EЈ) was higher and peak late mitral annular velocity (AЈ) was lower in young vs. older men (P Ͻ 0.01). A significant interaction effect was found for AЈ, EЈ/AЈ, and peak systolic mitral annular velocity (SЈ). Training was associated with lower AЈ in young and higher AЈ in older men. SЈ was greater in trained vs. untrained older men (P Ͻ 0.05), but it was similar in trained and untrained young men. These findings suggest that early diastolic filling is not affected by training in older men, and the effect of training on AЈ and SЈ is different in young and older men. diastolic function; aging; endurance training; maximal aerobic capacity (maximal oxygen consumption), tissue Doppler imaging AGING IS ASSOCIATED WITH AN increase in left ventricular stiffness (7), which results in a prolongation of isovolumic relaxation time (9) and incomplete relaxation of the ventricle during early diastolic filling (25). Numerous investigations have shown that peak early diastolic mitral inflow velocity (E) is reduced in aged individuals (2,10,17,18,34). To maintain ventricular filling and stroke volume, peak late diastolic filling velocity (A) increases with age (2, 17), resulting in an age-associated decline in the early-to-late mitral inflow velocity ratio (E/A) ratio (17).Aerobic fitness is associated with improved early diastolic function in young healthy subjects. Young trained athletes have increased E (20) and E/A (8, 11, 22, 26) compared with their nontrained counterparts. However, evidence to suggest that training has a similar effect in older athletes, or that training attenuates the normal age-associated decrease in E/A is inconclusive (8,10,28,31). Endurance training has been shown to improve peak filling rate in older healthy men (19), and the E/A has been shown to be higher in highly trained older endurance athletes compared with agematched healthy controls (8). However, Fleg et...