1. The role of cardiac output limitation in the pathophysiology of exercise in @entity1 with @entity454 remains undefined. During steady-state submaximal exercise, @entity26 uptake is similar in @entity1 and control subjects, but it is not known if cardiac output is also similar. We wished to determine if the reduced exercise tolerance of @entity1 with @entity712 during such exercise is related to @entity998 , or to peripheral factors. 2. Ten male @entity1 with stable @entity454 and ten age-matched male normal controls were studied at rest and during exercise. Each subject performed a familiarization exercise test, a symptom-limited maximal exercise test and two submaximal exercise tests. Cardiac output was measured by a @entity544 rebreathing method. We also measured @entity26 consumption, ventilation, Borg score of perceived exertion and venous @entity880 concentration, and ejection fractions. 3. As expected, @entity1 had lower peak @entity26 consumption [median (range) 1.18 (0.98-1.76) versus 1.935 (1.53-2.31) l/min; P < 0.001], lower peak venous @entity880 concentration but a similar overall level of perceived exertion. At the same submaximal workload, @entity1 and control subjects had similar @entity26 consumption [0.67 (0.59-0.80) versus 0.62 (0.52-0.82) l/min] and cardiac output [6.92 (5.79-9.76) versus 7.3 (5.99-10.38) l/min] but the @entity1 had a greater perceived level of exertion [Borg score: 4 (1-6) versus 3 (1-5); P < 0.005], higher venous @entity880 concentration [1.6 (1-3.3) versus 1.14 (0.7-1.7) mmol/l; P < 0.05] and higher heart rate [106 (89-135) versus 87 (69-112) beats/ min; P < 0.005]. 4. During submaximal exercise at a similar absolute workload, @entity1 with @entity712 have a similar @entity26 uptake and cardiac output but greater anaerobiosis and increased fatigue when compared with normal subjects. These findings appear to relate predominantly to changes that occur in the periphery rather than abnormalities of central cardiac function.

Non-invasive measurement of cardiac output and ventricular ejection fractions in XXXX : relationship to impaired exercise tolerance.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity712 :: ('MESH:D006333', 'Disease') :: ['chronic cardiac failure', 'cardiac failure'] @entity998 :: ('MESH:D002303', 'Disease') :: ['reduced cardiac output'] @entity26 :: ('MESH:D010100', 'Chemical') :: ['oxygen'] @entity880 :: ('MESH:D019344', 'Chemical') :: ['lactate'] @entity544 :: ('MESH:D002245', 'Chemical') :: ['carbon dioxide'] @entity454 :: ('MESH:D007676', 'Disease') :: ['chronic failure']
@entity712 :: (MESH:D006333,Disease) :: ['chronic cardiac failure']
