| Historically, patient had to have a strict bed rest for 6 to 8 weeks after acute myocardial infarction (AMI). The fear was that physical activity would lead to the formation of ventricular aneurysm, heart failure, cardiac rupture and sudden death. But studies that questioned the efficacy of prolonged bed rest appeared lately. The results showed that bed rest has many adverse effects. Thereafter, clinicians gradually became aware that early mobilization might not be harmful and could avoid some of the complication of bed rest, such as pulmonary and deconditioning. Now many clinicians believe that the limits of activity should be extended. In most cardiac rehabilitation program, it is suggested that mobilization begin 1? days after infarction. But scientific bases for the early ambulation protocol is not enough, so it is difficult to decide on exercise frequency, time and format. This is one of the most important barriers to the prevalence of early exercise therapy. The purpose of the present study was to examine the effects of various activities, including a kind of lower limb exercise, deep respiration and some nursing intervention, in-patients with AIvll in acute stage. Before and after these activities vital signs and electrocardiogram were recorded. The main parameters that were measured included: blood pressure (BP), heart rate (HR), Double-Product (D-P), indexes related to QT dispersion and some time-domain index describing heart rate variability (I-IRV). Part 1. Effects of early limb exercise on heart in AMJ patient. in this study, 32 AMI patients were investigated without severe complications such as congestive heart failure, cardiogenic shook or vital hypotesion. All patients were allowed to perform a low intensity limbs exercise and a loading exercise within 24h after they had come in the emergency intensive care unit. The variation of myocardial oxygen consumption(MVO2), QTd, I]IRV and hemodynamics were evaluated after the mobilization. Some parameters were compared between the two exercises.Main results f @QTd. QTcd. JTd and JTcd changed non-significantly after the lowintensity limbs exercise. It meant that regionaI homogeneity of ventricular repoIarizationunchanged after the exercise. @RR, axmax, RRmin reduced after the low intensity Iimbsexercise, though SDNN, rMSSD increased significantly. This reSult suggests that mobi1izationof this intensity might not be harmful to sympathovagal balance. @After low intensity limbsexercise, bIood pressure was kept at the level of the formeT, and heart rate increased genially.Compared to low intensity limbs exercise, loading exercise not only resu1ted in a greater heartrate, but also a highIy blood pressure.@The main effects of low intensity limb exercise onhemodynamic included increase of total peripheral resistance (TPR), reduction of strokevolume and unvariation of cardiac output (CO). But after the Ioading exercise, both SV andCO increased, though TPR was reduced. @There were no significant differences betweennormal and mobilization condition.PartII: Effcts Of deeP breathing on heart in AMIpatienL The subjects investigatedin this part were the identical ones that in part I .The participants were instructed to breathdeeply at a frequency of 6 cycIe min-1in supine position. BefOre, during and after the deepbreathing, the parameters were measured. ResuIts: @Aner 5min deep breathing, QTc andQTmin prolonged, but QTmax unchanged. So QTd and Corrected QT Dispersion (QTcd)decreased. It raised the possibility that homogeneity of ventricular repolarization had beenimproved after deep breathing. @When the patient breathed deeply, bsa root mean squareof successive differences (rimSD) and standard deviation in N-N intervals(SDNN) increased... |
PDF Full Text Request