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- Andersson, Lars-Göran, et al.
(författare)
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Thallium-201 Myocardial Imaging at Rest in Male Orienteers and Other Endurance Athletes
- 2001
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Ingår i: Upsala Journal of Medical Sciences. - : Uppsala Medical Society. - 0300-9734 .- 2000-1967. ; 106:1, s. 59-66
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Tidskriftsartikel (refereegranskat)abstract
- During the period 1979 to 1992, 16 sudden unexpected cardiac deaths were known to have occurred in young Swedish orienteers. Autopsy indicated myocarditis to be the most frequent finding, most often combined with extensive myocardial fibrosis. The aim of the present investigation was to explore whether young male orienteers show a higher frequency than other young elite endurance athletes (controls) in the occurrence of Thallium-201 myocardial perfusion defects at rest, suggestive of fibrosis evoked by myocarditis. Thallium-201 perfusion abnormalities at rest were more frequently found in the controls than in the orienteers (26% vs. 12%, p=0.03). Uneven Tl-201 perfusion was associated with left ventricular mass (r=0.32, r=0.24, p<0.01, p=0.02) and body weight (r=0.30, r=0.31, p<0.01, p=0.03) in orienteers and controls, respectively. Echocardiographic left ventricular wall motion abnormalities were found in 11 athletes (9 orienteers and 2 controls) but only two displayed an abnormal Thallium-201 perfusion scan at rest. Perfusion abnormalities at rest did not occur more frequently in the orienteers but were commonly found in both groups of apparently healthy athletes making it futile to discern abnormals from normals. Thallium-201 perfusion aberrations were not associated with left ventricular wall motion abnormalities obtained by echocardiography.
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| 2. |
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| 3. |
- Henriksen, Egil, et al.
(författare)
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Doppler transmitral and pulmonary venous flow in young orienteers and sedentary young adults
- 2000
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Ingår i: Echocardiography. - : Wiley. - 0742-2822 .- 1540-8175. ; 17:2, s. 133-139
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Tidskriftsartikel (refereegranskat)abstract
- Doppler filling indices may provide important information on left ventricular diastole and possibly diastolic adaptation in endurance athletes. We therefore undertook a comparative study to obtain reference values for transmitral and pulmonary venous Doppler flow velocities and to characterize differences between young orienteers and young sedentary adults. Seventy-six elite orienteers (42 female and 34 male; 17-30 years old) and 61 sedentary young subjects (32 female and 29 male; 17-33 years old) underwent echocardiography. No significant differences between the athletes and sedentary controls regarding peak transmitral flow were found, although the athletes had significantly higher peak pulmonary flow velocity during diastole than the sedentary controls (0.69+/-0.13, 0.61+/-0.10, 0.78+/-0.12, and 0.57+/-0.09 m/sec for female athletes, female sedentary controls, male athletes, and male sedentary controls, respectively). Because no significant differences were revealed in the transmitral flow velocities between the athletes and the sedentary subjects, the relative force between the left atrium and the left ventricle should not diverge during early filling. An increase in pulmonary venous pressure or a decrease in left atrial pressure can augment the force between the pulmonary veins and the left atrium. A rise in pulmonary venous pressure is a hemodynamically unlikely adaptation in endurance athletes; therefore, to maintain the same transmitral pressure with an assumed lower left atrial pressure, the data suggest a more rapid relaxation and an improved left ventricular elastic recoil, which would enable the athletes to achieve a more rapid negative left ventricular pressure change during early filling.
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| 4. |
- Sundstedt, M., et al.
(författare)
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Left ventricular volumes during exercise in endurance athletes assessed by contrast echocardiography
- 2004
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Ingår i: Acta Physiologica Scandinavica. - 0001-6772 .- 1365-201X. ; 182:1, s. 45-51
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Tidskriftsartikel (refereegranskat)abstract
- Aim: The objective was to assess left ventricular (LV) volumes at rest and during upright submaximal exercise in endurance athletes to see whether changes in heart volume could explain the large predicted increase in cardiac output in endurance athletes. Method: Contrast echocardiography was used to assess changes in LV volumes during upright bicycle exercise in 24 healthy male endurance athletes. Maximal oxygen uptake and oxygen pulse were measured by using cardiopulmonary exercise testing. Results: From rest to exercise at a heart rate of 160 beats min(-1) end-diastolic volume increased by 18% (P < 0.001) and end-systolic volume decreased by 21% (P = 0.002). Stroke volume showed an almost linear increase during exercise (45% increase, P < 0.001). The increase in end-diastolic volume contributed to 73% of the increase in stroke volume. No significant differences were observed between stroke volume calculated from LV volumes with contrast echocardiography and stroke volume calculated from oxygen pulse at heart rates of 130 and 160 beats min(-1). Using the linear regression equation between oxygen uptake and cardiac output assessed by echocardiography during exercise (r = 0.87, P = 0.002), cardiac output at maximal exercise was estimated at 33 +/- 3 L min(-1), with an estimated increase in stroke volume by 69% from rest to maximal exercise. Conclusion: By using contrast echocardiography, a large increase in stroke volume in endurance athletes could be explained by an almost linear increase in end-diastolic volume and an initial small decrease in end-systolic volume during incremental upright exercise.
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