Abstract | BACKGROUND: METHODS: Subjects (24 heart transplant recipients and 25 healthy controls) exercised on a treadmill using pediatric ramp protocols. We measured heart rate (HR), blood pressure, and metabolic data. Median age at transplantation was 20 days (range, 4 to 97 days). Age of recipients at exercise testing was 9.7 +/- 2.3 years and in healthy subjects was 10.5 +/- 1.4 years (p=not significant [NS]). RESULTS: Exercise duration was similar in both groups (10.3 +/- 2.0 minutes in recipients vs 11.1 +/- 1.5 minutes in healthy subjects, (p=NS). Heart rate at rest was greater in recipients (94 +/- 15 beats per minute [bpm] vs 85 +/- 11 bpm, p=0.02). Peak HR also was less in the recipient group (158 +/- 15 bpm vs 189 +/- 12 bpm, p <0.001). Peak oxygen consumption was 14% less in the recipients (32.3 +/- 5.6 ml/kg/min vs 36.8 +/- 5.5 ml/kg/min, p <0.01). Ventilatory anaerobic threshold was decreased in recipients, 27.6 +/- 9.6 vs 32.8 +/- 6.0, p <0.05. Respiratory exchange ratio at peak exercise was equal in both groups (1.06 +/- 0.06 vs 1.06 +/- 0.08). Oxygen pulse index did not differ significantly, 5.5 +/- 1.1 ml/beat/m2 in recipients and 6.1 +/- 1.7 ml/beat/m2 in healthy subjects (p=NS). CONCLUSIONS: Overall, children who undergo cardiac transplantation in infancy have exercise capacities within the normal range. These recipients have a decreased heart rate reserve that may account for the differences in peak oxygen consumption when compared with healthy subjects.
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Authors | Ginnie Abarbanell, Neda Mulla, Richard Chinnock, Ranae Larsen |
Journal | The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation
(J Heart Lung Transplant)
Vol. 23
Issue 12
Pg. 1334-8
(Dec 2004)
ISSN: 1053-2498 [Print] United States |
PMID | 15607660
(Publication Type: Journal Article)
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Topics |
- Anaerobic Threshold
- Blood Pressure
- Child
- Exercise Test
- Female
- Follow-Up Studies
- Heart Rate
- Heart Transplantation
- Humans
- Hypoplastic Left Heart Syndrome
(surgery)
- Infant
- Male
- Oxygen Consumption
- Pulmonary Gas Exchange
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