A study on the mechanism of exercise therapy in cardiac patients in terms of the cardiac, peripheral and metabolic effects
Grant-in-Aid for General Scientific Research (C)
|Allocation Type||Single-year Grants|
Circulatory organs internal medicine
|Research Institution||St Marianna University School of Medicine|
MURAYAMA Masahiro St Marianna University School of Medicine, The Second Department of Internal Medicine, Professor, 医学部, 教授 (20010233)
|Project Period (FY)
1990 – 1992
Completed(Fiscal Year 1992)
|Budget Amount *help
¥2,500,000 (Direct Cost : ¥2,500,000)
Fiscal Year 1992 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1991 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Fiscal Year 1990 : ¥700,000 (Direct Cost : ¥700,000)
|Keywords||exercise therapy / myocardial infarction / anaerobic threshold / peak VO_2 / cardiac output / stroke index / myocardial infarction. / peak VO_2 / cardiac index / deconditioning / rehabilitation|
(1)Recovery process of anaerobic threshold in association with exercise therapy for old myocardial infarction
This study was performed to evaluate the evolutional change of anaerobic threshold (AT) in the recovery phase of myocardial infarction (MI) and to evaluate the merit of using AT for exercise prescription. Subjects included 40 patients with MI who had completed the rehabilitation program during hospitalization and exercise therapy was continued after discharge with a protocol using the exercise level reaching the heart rate at AT (ATHR). Peak VO<@D22@>D2 and AT were determined by ramp protocol, exercise tolerance by Bruce protocol at 1, 3 and 6 months from the onset of MI. The following results were obtained ; 1)A positive correlation was noted between Peak VO<@D22@>D2 and AT and also between Peak VO<@D22@>D2 and exercise tolerance. Of these, the former was more closely correlated than the latter at each month. 2)A significant increase of AT and Peak VO<@D22@>D2 was noted within
3 months in the recovery phase of MI and no further increase was obtained after 3 months. 3)As determinant factors of increase in DELTA AT from 1 to 3 months, (1)absence of left ventricular aneurysm (VA). (2)daily total energy consumption (DTEC) of (] SY.gtorsim.[) 2,000 kcal and (3)AT at a month of <15m1/min/kg were significant. 4)AT/Peak VO<@D22@>D2, ATHR and Borg's indices were not significantly different among 1, 3 and 6 months. It was concluded that AT was useful for exercise prescription of OMI, and that presence of VA and DTEC of < 2,000 kcal might be limiting factor of promoting exercise therapy in the recovery phase of MI.
(2)Evaluation of Exercise Capacity and Cardiac Function after Cardiac Rehabilitation on Chronic Phase of Myocardial Infarction
This study was carried out to clarify how cardiac adaptation could contribute to the improvement of exercise capacity in the recovery phase of myocardial infarction (MI). I evaluated it by using anaerobic threshold (AT), cardiac index (CI), stroke index (SI) and their interrelations.
Subjects included 25 patients with MI (19 male, 6 female, mean ago 62.1) who had finished cardiac rehabilitation program during acute phase and carried out exercise therapy after discharge with the level of AT measured at 1 month (M) after the onset of MI. At 3M after the onset of MI, AT was measured again and comparison was made between at 1 and 3M.
CI and SI were measured by CO_2 rebreathing method at rest and the level of 80% of AT and the following results were obtained.
(1)AT and peak oxygen uptake increased during 1 to 3M. (2)Statistically significant prolongation of exercise time was noted. (3)CI and SI increased from 1 to 3M. (4)A positive correlation was noted between AT and SI at 3M. (5)A marked increase of AT, CI and SI was noted in subjects to whom intracoronary thrombolysis within 6 hours after the onset of MI was performed, and whom without showing left ventricular aneurysm. These results suggest that cardiac contribution to the improvement of exercise capacity could exist in exercise therapy at the chronic phase of MI. Less
Research Output (14results)