Effect of Cardiac Rehabilitation on Physiologic and Inflammatory Markers in Patients with Acute Myocardial Infarction

BACKGROUND AND OBJECTIVES: here are several reports of cardiac rehabilitation (CR) having beneficial effects on the reduction of cardiovascular mortality and in the prevention of recurrent coronary events in patient with myocardial infarction (MI). An 8-week CR program was investigated to see if it affected the prognostic factors, such as inflammatory markers, after acute MI. SUBJECTS AND METHODS: 33 male and 5 female patients, with a mean age of 55+/-10 yrs, were consecutively assigned to the CR (n=19) and the control (n=19) groups three weeks after acute MI. The 8-week CR program consisted of life style modification and aerobic exercise training. At the baseline, and after 8 weeks, the symptom limited exercise test and peripheral blood sampling were performed to measure the physiologic capacity, the serum levels of high sensitive C-reactive protein (hs-CRP) and the plasma levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha. The interval changes of each parameter were compared between the two groups. RESULTS: The interval increments of the maximal oxygen uptake (14.3% vs. 10.6%, CR vs. control group, p=0.014), anaerobic threshold (18.8% vs. 7.0%, CR vs. control group, p=0.044) and exercise duration (9.4% vs. 3.1%, CR vs. control group, p=0.009) were larger in the CR than in the control group. The magnitudes of the interval changes in hs-CRP, IL-6 and TNF-alpha, as inflammatory markers, did not differ between the two groups (p>0.05). CONCLUSION: This 8-week CR program demonstrated an improved exercise capacity for MI patients, but a larger clinical trial, with modified exercise intensity and duration, will be necessary to detect any possible effect on the inflammatory markers.

Investigation of Espoused Theories in Nursing Practice / 성인간호학회지

As a nursing practice involves nurses'actions in a specific context of health care, this study has focused on exploring the espoused theories in nursing practice within the action science perspectives. Espoused theories are the belief, principles, and rationale expressed by the practitioner as guiding her/his actions in a situation of practice. The data were analysed qualitatively and 25 elements of espoused theories of nursing action were identified and clustered into 6 categories. The 25 elements of espoused theories are as follows: The clinical nurse worked in wholistic and individual nursing, focussed on the patient's needed, comfort and supportive nursing (5 theories of nursing goal); excellent skills, knowledge based, assessment and data collection, explaining, educating or a scientific basis(6 theories of nursing intervention): advocacy, value oriented, treatment, accountability and commitment(4 theories of nursing ethics); human respect, partnership, trust(3 theories of patient-nurse relationship) : knowledgable, accumulated clinical experiences and personally lived experiences, positive perspectives(4 theories of nurse), role of intervention, rewarding, peer relationship(3 theories of situations). The above mentioned espoused theories are similar to that of nursing textbooks which students learned through basic nursing education and almost the same as the Acts ofa Nurse in Korean. However, we are doubtful whether nurses actually do as they think. Therefore, it is recommended to review the theories-in-use in order to find any discrepancies between the espoused theories and the reality of nursing actions.

Analysis of the Endothelial Nitric Oxide Synthase and -fibrinogen Gene Polymorphism in the Development of Acute Myocardial Infarction in Korean Men

BACKGROUND AND OBJECTIVE: The aging process affects the responsiveness and other functions of endothelium and vascular smooth muscle cells, predisposing the old vessels to the development of atherosclerotic lesions. Endothelial nitric oxide synthase (ecNOS) gene polymorphism was shown to affect the occurrence of acute myocardial infarction (AMI). We hypothesized that aging may affect the association between the ecNOS gene polymorphism and AMI. METHODS: We investigated the age-related distribution of the ecNOS gene a/b polymorphism in 121 male AMI patients and 206 age-matched healthy male controls. As a control, we also genotyped b-fibrinogen gene H1/H2 polymorphism in the same population. RESULTS: The aa, ab, and bb genotypes were found in 1, 49 and 156 cases among the control subjects and 5, 23 and 93 cases among the AMI patients, respectively. There was a significant association between the ecNOS polymorphism and AMI (p=0.045). When the correlation was analyzed by age, the significance remained only in the group below the age of 51 (p=0.009). The distribution of the b-fibrinogen gene H1/H2 alleles, however, was not found to be associated with development of AMI in both young (p=0.7400) and old (p=0.2160) population. CONCLUSION: Our results provide the first evidence that links ecNOS polymorphism to the risk of AMI in relation to age. Young persons who smoke or have ecNOS aa genotype may have an increased risk of developing AMI. The functional as well as structural changes associated with aging in the vascular endothelium may mask the effect of the ecNOS polymorphism in the development of AMI in old people.

The Correlation between Coronary Artery Disease and Carotid Atherosclerosis

BACKGROUND: In patients with coronary artery disease (CAD), atherosclerotic changes of carotid arteries (CA) often coexist with CAD itself. If the degree of carotid atherosclerosis can be estimated, it would be very helpful in the management of patients with CAD. METHODS: CA intima-media thickness (IMT) was evaluate by ultrasonography at 12segments (both proximal, middle, distal common CA, bifurcation, internal and external CA-of the extracranial CA) on the 182 subjects whom underwent coronary angiograms. The subjects were divided into 4 groups according to the severity of CAD; control (C, n=23), single vessel disease (1, n=64), two vessel disease (II, n=44), three vessel disease (III, n=51). RESULTS: The means (+/-SD) of maximal IMT, chosen from the 12 segments, of each group were 1.4+/-0.7mm (C), 2.1+/-1.4mm (I), 2.2+/-1.2mm (II), and 2.9+/-1.7mm (II). The 4 groups showed significant differences between each other. The only conparison to yield unsignificant differences was between group I and group II (p=0.02 for C and I, p=0.001 for C and II, p<0.001 for C and III, p=0.01 for I and III, p=0.04 for II and III). When multivariate analysis was used to assess which major risk factors for CAD (age, male sex, smoking, hypertension, diabetes, cholesterol, triglycerides and CAD groups affected CA IMT), group III and increasing age were the most significant variables (p=0.0001 and 0.0035, respectively). CONCLUSIONS:It is necessary to evaluate the status of the extracranial carotid arterial system with ultrasonography in patients with three vessel CAD even if neurologically symptomless. It becomes especially evident in elderly patients.

Effects of Cardiac Rehabilitation in Patients with Myocardial Infarction

BACKGROUND: Since the 1980s, early ambulation and cardiac rehabilitation have been emphasized in clincal practice after myocardial infarction. This is based on the belief that cardiac rehabilitation can reduce cardiovascular mortality, improve functional capacity and reduce the risk of further coronary events. In this study, we investigate the effect of aerobic exercise-based cardiac rehabilitation on functiona capacity and cardiopulmonary response in patiets with myocardial infarction. METHODS: 19 patients were divided into two group(9 patients for training group and 10 patients for control group) at 4-6 weeks after acute myocardial infarction. Training group performed aerobic exercise for 8 weeks(3 sessions per week, mean 53mins per session) at 40-60% of heart rate(HR) reserve, while control group did not. Before and after 8 weeks, all patients performed symptom-limited exercise test using modified Bruce protocol. Also, breath by breath respiratory gas analysis was carried out throughout exercise test. RESULTS: For body composition, body weight(-2.7%, p<0.001), body mass index(-2.5%, p<0.001) and %body fat(-2.6%, p<0.05) were decrease significantly in training group after 8 week cardiac rehabilitation. Resting HR(-13%, p<0.05) was reduced significantly in training group, but no significant change occured in resting blood pressure between the two groups. Maximal oxygen uptake(18%, p<0.01) and anaerobic threshold(21%, p<0.05) were increased significantly in training group after 8 week cardiac rehabilitation as compared with the control group. There was no significant change in maximal O(2)pulse between the two groups. Submaximal rate-pressure product(-17%, p<0.05) and submaximal rate of perceived exertion (-2.6, p<0.001) were decreased significantly in training group after 8 week cardiac rehabilitation as compared with the control group. CONCLUSIONS: Our findings indicate that cardiac rehabilitation results in the significant improvement of functional capacity and cardiopulmonary response in patients with myocardial infarction. Cardiac rehabilitation for patients with myocardial infarction can contribute early return and readaptation to normal life, because myocardial oxygen consumption(or rate-pressure product) is decreased at the same exercise level after exercise training.

Influences of the Apolipoprotein E Polymorphism on the Development of Coronary Artery Disease and on Serum Lipids in the Korean Males

BACKGROUND: Apo E lipoprotein is polymorphic and exists in three common isoforms (E2, E3 and E4), which are the gene products of three apo E alleles, e2, e3 and e4. Apo E lipoprotein plays an important role in the regulation of the lipid metabolism through its ability to bind to receptors. Depending on the genotypes apo E polymorphism is either protective or increases risk for atherosclerosis and coronary artery disease. The purpose of this study is to evaluate 1) the association between apo E allele and the development of coronary artery disease, 2) the association between apo E alleles and dyslipidemia in Korean males. METHODS: We studied 241 patients with angiographically verified coronary artery disease and 257 male subjects without evidence of coronary artery disease. Apo E genotyping was determined with the INNO-LiPA Apo E kit (Innogenetics, Belgium), which is based on reverse hybridization. RESULTS: There was a higher frequency of the apo e4 allele in subjects with coronary artery disease than in normal controls. The frequencies of apo E genotype were not significantly associated with apo e2 were associated with higher levels of triglyceride and lower LDL, and the subjects with apo e4 had lower levels of HDL cholesterol. CONCLUSION: ApoE polymorphism is a genetic marker for risk of the development of coronary artery disease and an important determinant of dyslipidemia.

The Effect of Beta-blocker Assessed by Repeat Head-up Tilt Test in Adults with Vasovagal Syncope or Presyncope

BACKGROUND: Oral beta-blocker is initially used to prevent the symptons in patients with vasovagal syncope or presyncope. But, beta-blocker treatment may actually cause worsening of symptoms in some patients. The purpose of the present study was to evaluate the efficacy of oral beta-blocker in preventing symptoms during repeat head-up tilt test in patients who had a positive response in initial head-up tilt test. METHOD: Patients. Among the 150 patients with unexplained syncope or presyncope who underwent head-up tilt from October 1994 to January 1996, forty-three patients, who were taking beta-blocker and underwent repeat head-up tilted test, were included in this study. Initial head-up tilt test. Each patients was tilted to the 70 degree upright position for 30 minutes. If the test was negative in the baseline tilt, intravenous isoproterenol was started at 1 (micro)g/min and then increased by 1 (micro)g/min every three minutes to al maximum of 5 (micro)g/min while maintaining 70 degree upright position. Repeat head-up tilt test. The test was repeated while each patients was taking atinolol. The repeat test was continued until reaching at the stage where each patient had a positive response in initial test. RESULTS: 1) In initial head-up tilt test, most (91%) of a positive response occured during isoproterenol provocation. 2) In repeat head-up tilt test on atenolol, thirty-four patients(79%) had a negative response. But nine patients(21%) still had a positive response. 3) Nonresponsive group showed younger age and shorter time period to a positive response in initial head-up tilt test than responsive group. CONCLUSION: It may be useful to assess the effectiveness of beta-blocker by repeat head-up tilt before deciding long term treatment, especially younger age group.

Correlation between Apolipoprotein E Polymorphism and Plasma Lipid Levels in the Korean Males

BACKGROUND: Apo E lipoprotein is made up of 299 amino acid and is classified into three major isoforms(E2, E3 and E4). Aop E lipoprotein plays an important role in the regulation of the lipid metabolism. The purpose of this study is to evaluate the variations of plasma lipids depending on the apo E genotype in the Korean males. METHODS: We studied 257 male subjects without evidence of coronary artery disease. Apo E genotyping was determined with the INNO-line probe assay apo E test, which is based on reverse hybridization. RESULTS: Apo E genotype frequencies for 257 subjects were as follows, 73.9% for epsilon3/3, 16% for epsilon4/3, 8.2% for epsilon3/2, 1.2% for epsilon2/2, and 0.8 for epsilon4/4. We found significant differences in apo E allele frequencies of our subjects campared with those of western populations. Compared to the subjects with apo epsilon3, the subjects with apo epsilon2 was associated with higher levels of triglyceride, and the subjects with apo epsilon4 had lower levels of HDL cholesterol. CONCLUSION: The frequencies of apeE genotype varies depending on the ethnic origin. ApoE polymorphism plays an important role in determining individual differences in plasma lipids.

Usefulness of Head-up Tilt Test in Adults with Syncope or Presyncope of Unexplained Origin

BACKGROUND: Vasovagal syncope is a common cause of syncope. In some cases, syncopal episode is recurrent, resulting in physical injury. Head-up tilt test with or without isoproterenol provocation has been a tool to diagnose vasovagal syncope. But the protocol of head-up tilt test has not been settled. In this study, we evaluate the usefulness of a head-up tilt test with isoproterenol provocation in patients with syncope or presyncope of unexplained origin. METHODS: Head-up tilt test was performed with patients in the fasting state in the morning. After supine heart rate and blood prewwure were obtained, each patient was tilted to the 70 degree upright position for 30 minutes using a motorized tilt table with a footboard. If the test was negative in the baseline tilt, intravenous isoproterenol was started at 1 microg/min and then increased by 1 microg/min every three minutes to a maximum of 5 microg/min while maintaining 70 degree upright position. The end points of test were positive response, intolerance of isoproterenol, heart rate>150 beats/min, and completion of the protocol. When an end point reached, the patient was rapidly returned to the horizontal position. RESULTS: 1) Of 122 patients with syncope or presyncope, 113 patients(93%) had prodromal symptoms. 2) 23 patients(19%) had physical injury during episode. 3) 93 patients(76%) experienced episodes while they were standing or sitting. 4) A total of 83 patients(68%) had a positve response during head-up tilt test ; 7 patients(8%) of these 83 patients had a positive response during the baseline tilt. But, 76 patients(92%) required isoproternol provocation to elicit this response. 5) The pattern of positive response showed vasodepressive pattern in 55 patients(67%), mixed pattern in 26 patients(31%), and cardioinhibitory pattern in 2 patients(2%). 6) No significant side effect of isoproterenol was noted. 7) There were no significant differences between positive response group and negative response group in terms of clinical characteristics and hemodynamic findings during head-up tilt test. CONCLUSION: A head-up tilt test with isoproterenol provocation could be an useful tool for diagnosing vasovagal syncope or presyncope in adults.