The Improvement Of Cardiopulmonary And Cardiac Autonomic Function, And The Relationship Between Them In Elderly Patients With Coronary Heart Disease During Cardiac Rehabilitation

Objective：Aim to research the change of the cardiopulmonary functionand the modulationof Autonomic Nervous System in patients with coronary heart disease during differentphases of cardiac rehabilitation (CR)(12weeks and12months).and to investigate therelationship between the change of the cardiopulmonary function and and themodulation of autonomic nervous system in patients with coronary heart disease.Methods:15patients with coronary heart disease were selected as the (coronary heartdisease，CHD) group, and15ages matched non coronary heart disease people wererecruited as a heathy control group（HC）.All subjects undertook a Symptom-limitedmaximal load exercise test on a treadmill (the modified Bruce protocol) during whichtime aerobic working capacity was measured and electrocardiogram (ECG) wasmonitored throughout. Five minutes short-term process of heart rate variability (HRV)frequency domain method was applied pre-and post-exercise test to determine thesubjects’ HRV at rest and recovery phases. After that, CHD group attended a12-weeksupervised exercise-based cardiac rehabilitation programme. The HC group did notparticipate in the organized training, just to maintain daily activities. After12weeksof rehabilitation exercise, CHD group were re-tested for the cardiovascular functionand heart rate variability. After that, CHD group to continue its home-andcommunity-based rehabilitation(the second phase of cardiac rehabilitation exercise).The training lasted for12months. After12months CR, both CHD group and HCgroup undertook the measurement of HRV and cardiopulmonary functionand onemore times.Results: 1. Before attending rehabilitation exercise, CHD group showed significantly lowervalues of cardiac function including SV、CI、EF%、△D%（p<0.01，p<0.05）,cardiac function indicators DSD and ESV were significantly higher than HC（p<0.01，p<0.05）,and aerobic capacity interms of peak exercise time、HRpk,、METspk,、VO2/HRpk,、HR@VAT,、HR@VAT/HRmax%compared with HC（p<0.01，p<0.05）.2. After a12weeks CR, The CHD group significantly reduced its cardiac function（DSD、 ESV）（p<0.05），and imprived its cardiac function（SV、CI、EF%、△D%）（p<0.05，p<0.01）;Aerobic capacity indicators (HRpk, METspk, peakexercise time, exercise time@VAT, exercise grading@VAT) were significantlyhigher than before the training (p <0.05).3. CHD group after12months of rehabilitation exercise, compared with12weeks ofrehabilitation exercise, cardiac function and aerobic capacity has increased theoverall trend, but the difference was not statistically significant; Compared withbefore attending rehabilitation exercise, cardiac function and aerobic capacitywere significantly improved（p<0.05，p<0.01）.4. Before attending rehabilitation exercise, CHD group showed significantly lowervalues of heart rate variability（TP、VLF、LF、HF）compared with HC（p<0.05）,LF/HF index of the CHD group was significantly higher than HC group（p<0.05）;After ET（exercise test）, LF index of the CHD group significantlyhigher than at rest, Other indicators showed no significant difference. HC groupshowed lower value of heart rate variability（TP、VLF、LF）, but difference didnot reach the significant level. HF index was significantly lower than at rest(p<0.05), LF/HF was significantly higher than at rest (p <0.05).5. After a12weeks CR, The CHD group significantly improved its heart ratevariability(TP、LF、HF)（p<0.05）. LF/HF tended to decrease, but difference didnot reach the significant level,VLF tended to increase but again the difference didnot show significance. After ET, The CHD group had tended to decrease in their measurement of heart rate variability(TP、VLF、HF) compared with that at rest.but difference did not reach the significant level,the indexes of heart ratevariability(LF、LF/HF) had tended to increase but again the difference did notshow significance.6. CHD group after12months of rehabilitation exercise, compared with12weeks ofrehabilitation exercise, LF index significantly decreased (p <0.05), Otherindicators showed no significant difference. Compared with the previousrehabilitation exercise, TP showed significantly increased (p <0.05), The indexesof heart rate variability (LF、HF) have a increasing trend,LF/HF had tended todecrease but the difference was not statistically significant.；After ET, CHD grouphad tended to decrease in HRV compared with at rest,but difference did not reachthe significant level.Conclusion:1The heart function and aerobic capacity of patients with coronary heart diseasehas increased during12weeks cardiac rehabilitation exercise, in the meantimeCHD patients also indicated on cardiac autonomic regulation function hasimproved to some extent, the ability to regulate sympathetic and vagal functiontends to a higher level; Long-term for adherence of exercise(12month family andcommunity rehabilitation exercise)might enable patients to maintain theimprovements obtained already in functions of both cardiopulmonary functionand autonomic nervous.2There is a close relationship between cardiorespiratory function and the ability toregulate the function of cardiac autonomic nervous in elderly patients withcoronary heart,the two factors in the relationship will both interacted and mutualimproved each other.