Preventive Cardiology - Epidemiology and Prevention of Cardiovascular Diseases

No abstract available.

The Evaluation of Coronary Artery Stenosis by Exercise-Induced Negative U Wave

BACKGROUND: Negative U wave is frequent maker of systemic hypertension, aortic or mitral regurgitation and myocardial ischemia. This study was undertaken to determine the diagnostic significance of exercise-induced negative U wave in coronary artery stenosis. METHOD: 72 patients(46 men and 26 women ; 24~66 years of age) with chest pain were analysed with exercised-induced negative U wave and coronary angiographic finding. RESULT: Exercise-induced negative U wave was seen in 14 patients(19%). Among 14 patients with exercise-induced negative U wave, the predictive value of significant coronary artery stenosis(> or =75% stenosis of major coronary artery) was 71%, Exercise-induced negative U wave is more prevalent in patients with significant coronary artery stenosis(p<0.05). CONCLUSION: Exercise-induced negative U wave is a good marker of significant coronary artery stenosis.

Cell and Molecular Biology of Medicine and Cardiovascular System in Normal and Diseases

No abstract available.

The Experience of Percutaneous Transluminal Coronary Angioplasty (PTCA) on the 25 Patients with Coronary Artery Disease

PTCA has been widely applied in patients with symptomatic coronary artery disease since 1977. The PTCA was performed on a total of 25 patients (19 men and 6 women) from Feburary 1988 to January 1990 at Inje University Baik Hospital. Their mean age was 51.4+/-10.1 years. The 20 patients had unstable angina, and 5 patients had stable angina. The 6 patients had a previous myocardial infarction. The 17 patients had one vessel disease, 6 patients had two vessel disease and 2 patients had three vessel disease. Primary success was achieved in 24 of 25 patients. The mean degree of stenosis was reduced from 80.7+/-2.9% to 16.2+/-3.3% (p<0.01). After PTCA, pain was relieved or subsided in all patients. In 6 patients, mild chest pain has reccured during the short term follow up. Repeat PTCA was performed in 2 of 6 patients successfully. Complications occurred in 3 patients ; coronary artery spasm, ventricular fibrillation and femoral artery hematoma in each patients.

Effects of Pravastatin(Mevalotin(R)) on Hyperlipidemia

Effects of Pravastatin(Mevalotin(R)), a new HMG-CoA reductase inhibitor on the blood lipids were studied for the period of 3 months in 40 subjects with hypercholesterolemia more than 250mg/dl. Age of the subject was 50 years in average with range of 34 to 72 years. There were 22 cases of male and 18 cases of female. The cause of hyperlipidemia was not specified, but there were no case of liver, thyroid and renal disease. The 10mg of Preavastatin was given in devided doses in the morning and at bed time for 3 months. Serum LDL-cholesterol, total cholesterol, HDL-cholesterol, triglyceride and atherogenic index were measured before and after the medication in every month and following results were obtained. 1) Serum cholesterol decreased maximally at 2months after the medication with average decrease of LDL-cholesterol 79.8mg/dl(43%), serum total cholesterol 99.8mg/dl(34%) and the atherogenic index 3.0(45%). The decrease of total serum cholesterol was dependent on the pretreatment level. 2) The serum triglyceride decreased in average 81mg/dl(26%) in one month after the medication however the change was not statistically significant because of wide variation. 3) The HDL-cholesterol decreased in average 1.6mg/dl(4%) in one month and statistically significant. 4) The serum total cholesterol started to change in 3 days and tended to decrease with unstable variation up to the end of 2 weeks after the medication. In one month after cutting drug, there were slight increase of cholesterol but did not return to control value. 5) The significant effect of blood lipid lowering drug in non-specific hyperlipidemia should be evaluated when the changes are more than intra-individual variation of blood lipids. 6) There were only 2 cases of side effect with epigastric pain and fullness which subsided soon and there was no change in liver functions, serum creatinine and fasting blood sugar after the medication. In conclusion, the pravastatin is an excellent new lipid lowering drug with safety.

Study on Korean Daily Walking Activity

Since there is no report of daily walking activity of Korean, authors studied on normal adult daliy walking activity in korean of various kinds of occupation, personal life and patients. Total 134 cases were studied and in which there were 10 patients, 7 retired elderlies, 4 house wives, 48 employees of compaines, 30 nurses, 4 laboratory technicians, 2 pharmacists, 7 house staff doctors, 12 chief doctors, 4 cases of hicking and 6 cases of 18 holes golf players. The daily walking steps were measured with pedometer in 167 times in total and following results were, obtained. 1. Bed rest patients ; less than 1000 steps/day 2. Retired elderly ; 2,724(2,150-3,500) steps/day 3. House wife ; 5,437(3,030-7,920) steps/day 4. High ranking, old clerk and chief doctor ; 5,000-6,000 steps/day 5. Ordinary non-active clerk and non-clerk employee ; 6,000-9,000 steps/day 6. common young active clerk and nurse ; 10,000-15,000 steps/day 7. Very active clerk and non-clerk employee ; 15,000(13,000-20,000) steps/day 8. Heavy worker ; more than 20,000 steps/day

Myocardial Structure and Dynamics and Indices of Cardiac Function

No abstract available.

Antihypertensive Effects of Nicardipine on Essential Hypertension with Cardiovascular Complications

The effects and safety of using oral Nicardipine(NCP, Perdipine(R)) a calcium blocking agent of the dihydropyridine derivative, were assessed in 29 patients(14 males, 15 females, mean age 56.3 years) with essensed hypertension with complications of left ventricular hypertrophy and/or hypertensive retinopathy. The patients with a sitting blood pressure(BP) of more than 160/100mHg at 4th week while off all antihypertensive agents, were entered into the study and recieved NCP, 20mg tid for 2 weeks, BP being measured once every week. NCP significantly reduced. The systolic BP from 179.5+/-18.2mmHg to 143.4 +/-18.2mmHg, the diastolic BP from 112.9+/-16.2mmHg to 93.1+/-10.4mmHg and the mean BP from 135.2+/-11.7mmHg to 110.0+/-9.9mmHg(mean+/-S.D. of weekly BP for 4 weeks)(P<0.001). Fall in systolic, distolic and mean BP was 35.1+/-15.1mmHg, 20.0+/-8.3mmHg and 25.3+/-10.2mmHg, respectively. A fall in systolic BP of more than 20mmHg, in diastolic BP of more than 10mmHg and in mean BP of more than 13mmHg was obtained in 86.2%, 89.6% and 86.2% of the cases, respectively. The heart rate did not change with oral NCP. The side effects were headache, facial flushing, dizziness and palpitation, but they were tolerable. These finding suggest that NCP is an effective and safe drug for the treatment of sustained essential hypertension.

Significance of ST-Segment Level, ST-Segment Slope, ST-Segment Index and ST-Segment Integral in Exercise ECG as an Indicator of Myocardial Ischemia

In an attempt to investigate which of the ST-segment parameters, e.g., ST-segment level, ST-segment slope, ST-segment index and ST-segment intergral obtained by mannual drawing can most sensitively indicate quantitatively the extent of exertional myocardial ischemia in patients with angina pectoris, 26 patients with angina pectoris underwent exrecise stress testing, using a bicycle ergometer and thallium-201 myocardial perfusion scintigraphy(Thallium-201 MPS). The exrecise was terminated either when symptoms or signs indicative of myocardial ischemia developed or when the heart rate reached the predicted maximal heart rate during exrecise. The myocardial ischemia region was quantitated by Thallium-201 MPS. The number of myocardial ischemia segments was similar in patients who had positive exrecise test(4.9+/-1.9) and in those who had negative result(3.7+/-2.2). However, it was greater in patients who showed pseudonormalization of the T wave in exercise ECG(6.3+/-2.6) than in those with negative exercise test(3.7+/-2.2)(P<0.05). The extent of myocardial ischemia region expressed by the number of myocardial ischemia segments correlates best with the ST-segment index(r=-0.83) among ST-segment slop(r=-0.60), ST-segment intergral(r=-0.59) and ST-segment(r=0.50). These data suggest that the ST-segment index is the most reliable indicator to reveal the extent of exertional myocardial ischemia among the ST-segment parameters and that pseudonormalization of T wave in exercise ECG is a finding indicative of exertional myocaridial ischemia in patients with angina pectoris.

Clinical Study on Cerebral Blood Flow in Korean Adult

Although measurement of cerebral blood flow by radioactive - isotope method became popular, there is still no report of study on the cerebral blood flow in Korea. Auther studied the regional cerebral blood flow in 28 normal Korean adults and and 76 patients including 14 cases of essential hypertension, 11 cases of heart diseases (coronary artery disease, valvular diseases and A-V block), 14 cases of brain diseases(cerebral thrombosis and cerebral insufficiency), 22 cases of head trauma and 15 cases of miscellaneous medical diseases. The regional cerebral blood flow was measured by intravenous in jection of (99m)Tc-DTPA 15-20Ci and by taking serial cerebral angiograms with CGR Gamma Tome 7000 and was analized by computer Imac 7310. The results were as follows: 1) The average regional cerebral blood flow of normal Korean adult was 50.0+/-5.89mg/100g /min. with range of 41-60ml/100g/min. 2) In most cases of essential hypertension the regional cerebral blood flow was within normal limit except rare case which was considered to have impaired autoregulation of cerebral blood flow. 3) In patients with myocardial infarction, valvular heart diseases with congestive heart failure and complete A-V block, there was markedly reduced cerebral blood flow. The reduced cerebral blood flow increased after the improvement of congestive heart failure and after the implantation of pacemaker. 4) In patients with cerebral thrombosis with infarction and cerebral insufficiency with symptoms of dizziness, headache or blurred vision, the cerebral blood flow was considerably reduced. However in acute encephalits the cerebral blood flow was increased. The measurement of cerebral blood flow by radioactiveisotope method is considered to be accurate, easy and useful clinical test to evaluate brain diseases and function.

Antihypertensive Effect of Low-Dose Clonidine Monotherapy

The antihypertensive effect of clonidine was evaluated in 129 patients with essential hypertension of mild to moderate severity with a dosage of one tablet(0.075mg) a day for 71 patients of Group I and two tablets a day for 58 patients of Group II. The results were as follows : 1) Of 71 patients of Group I, 34 patients(47.9%)showed good antihypertensive effect(greater than 15 mmHg drop in mean diastolic pressure) and 11 patients(15.5%) showed fair effect(10-14 mmHg drop in mean diastolic pressure). 2) Of 58 patients of Group II, 39 patients(67.2%) showed good effect and 7 patients(12.1%) showed fair effect. 3) The side effect observed was transient and tolerable dry mouth, which developed in 5.6% of Group I patients and 13.6% of Group II patients.

Studies on Platelet Aggregability in Thrombotic Disease and Hypercholesterolemia and Effects of Aspirin and Dipyridamole

Although platelet have been implicated in the pathogenesis of the thrombotic disease, the platelet aggregability was not well studied in Korea. Author measured platelet aggregability in 103 clinical cases including 30 healthy volunteers to evaluate the platelet function and the effect of Aspirin and Dipyridamole on aggregability in Korean. 24 patients with cerebral thrombosis, 24 patients with ischemic heart disease and 25 patients with hypercholesterolemia were included for this study. Aggregation tests were performed at three final concentrations of epinephrine(10microM/L) and ADP(4 microM/L, 10 microM/L) with platelet aggregometer which was made by Chrono-Log Corp. in all cases. Platelet aggregations were measured in patients who were treated with Aspirin, Dipyridamole and combined treatment of Aspirin and Dipyridamole respectively. The following results were obtained. 1) The mean maximal platelet aggregability in the normal subjects induced by 10 microM/L epinephrine was 59.3+/-24.26%, 66.6+/-14.00% in Bm and 62.5+/-19.30% in B5 in induction by 4 microM/L ADP, and 77.2+/-8.99% in Bm and 76.6+/-9.83% in B5 in induction by 10microM/L ADP. 2) The mean maximal platelet aggregability in patients with cerebral thrombosis induced by 10 microM/L epinephrine was 89.2+/-7.33%, 78.8+/-9.41% in Bm and 78.5+/-9.93% in B5 in induction by 4 microM/L ADP, and 86.4+/-7.69% in Bm and B5 in induction by 10 microM/L ADP. The results showed significantly elevated platelet aggergability than that of normal subjects(p<0.01). 3) The mean maximal platelet aggregability in patients with ischemic heart disease induced by 10 microM/L epinephrine was 88.1+/-11.99%, 78.2+/-12.50% in Bm and B5 in induction by 10 microM/L ADP. The results showed significantly elevated platelet aggregability than that of normal subjects(P<0.01). 4) The mean maximal platelet aggregability in patients with hypercholesterolemia induced by 10 microM/L epinephrine was 86.8+/-15.99%, 82.7+/-11.19% in Bm and 82.0+/-12.87% in B5 in induction by 4 microM/L ADP, and 88.5+/-11.47% in Bm and B5 in induction by 10 microM/L ADP. The results showed signifcantly elevated platelet aggregability than that of normal subjects(P<0.01). 5) The mean maximal platelet aggregability in patients with thrombotic disease was studied by Dipyridamole administration. The platelet aggregability induced by epinephrine before administration was 90.9+/- 8.52% and after administration it was 78.9+/-15.68%, and the results showed that Dipyidamole lowered aggregability significantly. The platelet aggregability induced by 4 microM/L ADP before administration was 84.0+/-11.90% in Bm and B5 and after administration it was 78.0+/-11.44% in Bm and B5, and the results showed that Dipyridamole lowered aggregability but not significant. The platelet aggregability induced by 10 microM/L ADP before administration was 89.2+/-10.39% in Bm and B5 and after administration it was 80.5+/-8.44% in Bm and B5, and the results showed that Dipyridamole lowered aggregability significantly. 6) The mean maximal platelet aggregability in patients with thrombotic disease was studied by Aspirin administration. The platelet aggregability induced by epinephrine before administration was 91.0+/-4.79% and after administration it was 47.6+/-17.72%. The platelet aggregability induced by 4 microM/L ADP before administration was 84.6+/-10.37% in Bm and B5 and after administration it was 72.6+/-11.85% in Bm and 65.3+/-15.97% in B5. The platelet aggregability induced by 10 microM/L ADP before administration was 84.9+/-6.30% in Bm and B5 and after adminstration it was 77.7+/-8.60% in Bm and 75.0+/-8.89%. The results showed that Aspirin lowered aggregability markedly. 7) The mean maximal platelet aggregability in patients with thrombotic disease was studied by combined administration of Aspirin and Dipyridamole. The platelet aggregability induced by epinephrine before administration was 86.7+/-13.77% and after administration it was 36.7+/-14.01%. The platelet aggregability induced by 4 microM/L ADP before administration was 81.5+/-12.93% in Bm and 80.6+/-14.15% in B5 amd after administration it was 54.7+/-17.27% in Bm and 44.6+/-21.17% in B5. The platelet aggregability induced by 10 microM/L ADP before administration was 87.8+/-10.11% in Bm and B5 and after administration it was 65.7+/-13.59% in Bm and 62.0+/-16.42% in B5. The results showed that combined administration of Aspirin and Dipyridamole lowered aggregability significantly and the results were lower than that of normal subjects. 8) The effects of combined treatment of Aspirin and Dipyridamole showed marked reduction of platelet aggregability than that of single treatment of Aspirin or Dipyridamole in thrombotic disease.

Clinical Study on the Effect of Diltiazem on Hypertension

The hypotensive action of calcium antagonist has been recognized, however, clinical study on the hypotensive effect is not yet extensively carried out. Auther studied the effect of Dilitiazem(Herben(R)) on 23 hypertensive patients. The age of patient was average 58.5(30-75) years. There were 8 male and 15 female patients. Among 23 cases, 20 cases of essential hypertension had no previous medication for hypertension and they were given 90mg of Diltiazem daily in 3 divied doses for 8 weeks. The blood pressure and pulse were measured at one week interval. In 3 cases of hypertension who were refractory to other hypotensive drugs for 2 weeks. The results were as follows; 1) In 20 cases of untreated essential hypertension, the control average blood pressure was 179.8/106.3mmHg and pulse 77.1/min. After the Diltiazem medication average blood pressure in one week was 153.3/97.3mmHg and pulse 76.6/min, in 3 week 153.0/94.0mmHg, and pulse 76.6/min, in 5 week 143.0/92.0mmHg and pulse 75.4/min, and in 8 week 142.3/90.0mmHg and pulse 73.0/min. These data showed that after one week of medication, blood pressure fell significantly in systole and diastole but there was no significant pulse change. 2) The rate of hypotensive effect by grade were as follows; overall effectiveness in systolic pressure which fell more than 5 mmHg was 85% and more than 20mmHg fall was 70%. In diastolic pressure the overall effectiveness which fell more than 5mmHg was 60% and more than 15 mmhg fall was 40%. 3) In 3 cases which were refractory to other hypotensive drugs, the hypertension became normal blood pressure in one day by 90mg Diltiazem and the fall of blood pressure persisted for 2 weeks by continuous medication.

Life Threatening Hemoptysis in Mitral Stenosis Treated by Emergency Mitral Commissurotomy

A 25-year-old 7 month pregnant woman with mitral stenosis was hospitalized because of life threatening hemoptysis dispite intensive medical treatment. Emergency mitral commissurotomy resulted in prompt cessation of hemorrhage and at nine months follows-up, the hemoptysis has not recurred. Mitral valve surgery appears to be consitently associated with rapid and sustained cessation of hemoptysis. Therefore, surgery should be considered in hemoptysis due to mitral stenosis, particulary when the danger of asphyxiation exists.

Clinical study on the Effect of Tripamide(Normonal(R)) in Hypertension

The Tripamide(Normonal(R)) is a new derivative of nonthiazide diuretic and hypotensive drug which was claimed to have less side effects than thiazide derivatives. Authors studied on the effect of Tripamide in 30 cases of hypertension. The 15mg of Tripamide daily as single dose was given for the period of 6 weeks and in each week, the blood pressure in sitting position was measured and also checked symptoms and side effects. In 13 cases which were not responded to 15mg, daily dose of 30mg were given. In 13 cases, Hb, Hct, blood sugar, serum uric acid, Na, K, Cl, GOT, GPT and creatinine were measured before and after the 6 week medication. Following results were obtained; 1) After one week medication of Tripamide 15-30mg daily, the hypotensive effect(B.P. more than 5 mmHg decrease) appeared in 83.3% of cases in systolic pressure and 76.7% in diastolic pressure. The marked decrease(more than 20 mmHg) of systolic pressure in 60% and of diastolic pressure in 33.3% of cases. The over-all average systolic and diastolic pressure decreased by 18.7/7.6 mmHg. 2) There were no statistically significant changes of Hb, Hct, fasting blood sugar, uric acid, creatinine, sodium, potassium, chloride, GOT and GPT. However there were one case of significant decrease of potassium and increase of blood sugar respectively by 30mg medication. 3) There was no weakness or fatigue by 15mg medication except 2 cases which complained of weakness by 30mg medication and there was no remarkable side effect such as rash. 4) In 6 cases which were refractory to other antihypertensive drugs including hydrochlorothiazide, there was hypotensive effect by switching hydrochlorothiazide to Tripamide. These observations showed that Tripamide(Normonal(R)) has hypotensive effect with 15 to 30mg per day in one week and thereafter the effect was stationary and there was much less side effect such as weakness than thiazide derivatives.

The Evaluation of Myocardial Dyskinesia in the Patients with Coronary Artery Diseases

The evaluation of the regional wall motion abnormalities were done in 16 patients with myocardial infarction and 9 patients with anginal pectoris by the two dimensional echocardiography. The regional wall motion abnormalities detected by the two dimensional echocardiography were the highly sensitive indexes of the location of infarction(sensitivity: 84.6%) and were well correlated with the sites of infarction of the 12-lead EKG. In the patients with myocardial infarction, the apex and the distal septum of the left ventricle were the most frequently observed regions with wall motion abnormalities, which comprised 60.7% of the regions with the abnormal wall motion. The frequency of the regional wall motion abnormalities were much less frequently seen in the patients with anginal pectoris. The severity and the extent of the regional wall motion abnormalities as well as the global function of the left ventricle were well correlated with the clinical course and the prognosis in the patients with myocardial infarction during the short term observation.

Study on Multistage Maximal Stress Exercise Test

The maximal stress exercise test was studied in 49 normal korean and 231 cases of various diseases. Bicycle ergometer was used in 122 cases and treadmill was used in 109 cases by modified Bruce protocol which was designed by author. The maximal heart rate, maximal work capacity, End point of maximal exercise and ST changes especially in coronary artery disease were investigated. Total 231 cases in cluded 8 cases of myocardial infarction, 46 cases of anginal pectoris, 91 cases of atypical anginal pain, 68 cases of hypertension and 18 and of diabetes mellitus. The results are as follows; 1. The maximal heart rate was markedly reduced in myocardial infarction(115/min. comparing 162/min. in normal) and slightly less reduction in angina pectoris. Also mild reductions were observed in atypical anginal pain, hypertension and diabetes mellitus. 2. The maximal work capacity was markedly reduced in myocardial infarction(93 wt comparing 180 wt in normal). It was only slightly reduced in anginal pectoris, atypical anginal pain, hypertension and diabetes mellitus which were not significantly reduced from that of normal, especially in anginal pectoris, the reduction on maximal work capacity was unremarkale comparing that of maximal heart rate. 3. The End point of maximal exercise test were exhaution in 34%, leg pain in 30%, maximal heart rate in 22%, ST depression more than 1 mm in 21%, dyspnea in 19%, anginal pain in 15% by bicycle ergometer, while by treadmill test, the End point were exhaution in 47%, dyspnea in 35%, Maximal heart rate in 22%, ST depression more than 1 mm in 19%, leg pain in 15% and anginal pain in 10%. 4. In coronary artery disease, the positive maximal exercise test(sensitivity) was 76% in treadmill test and 68% in bicycle ergometer test. 5. The ST changes among 231 patients druing the maximal exercise test occured in 47 cases(20%). In 43 cases the ST segment depressed more than 1 mm and the degree of depression ranged 1-3.5mm. The upward sloping type and horizontal depression type were equally common. There were 4 cases(1.7%) of ST elevation during exercise which returned to normal after exercise. There were 3 cases among 54 cases of coronary artery disease(5.5%) and 2 cases among 46 cases of anginal pectoris(4.3%). In one case of anginal pectoris with elevated ST segment, myocardial infarction occured in few days later. Therefore it appears that the variant angina in this study is very few.

Comparative Study on the Method of Study of Plasma Renin Activity in Out-Patient and Inpatient and their Values in Essential Hypertension

Since the Plasma-Renin Activity (PRA) value varies by many factors such as amount of sodium in-take, diuretics and posture, the basal PRA with double stimulated PRA measurement is most widely used. However the method of the study is different according to investigators and especially the PRA study in out-patient is not easy. Author attempted to establish an easy and reliable method of PRA study in out-patient and their data were compaired with those of in-patient by the study of 38 normal cases in 207 hypertensive patients. Twenty four hours urine and overnight urine sodium measurement showed that the overnight urine sodium was about 45% of that of twenty four hour urine. More than 70mEq of overnight urine sodium is considered to be borderline to neglect sodium intake for study. The PRA of normal adult was measured at 30 minutes and one hour rest in supine or sitting position after arrival to hospital. There were minor increase of PRA after 30 minutes and one hour rest than basal PRA which will not confuse the evaluation of PRA. After Lasix 40mg and 20mg intravenous injection with walking respectively, the PRA changes were measured in 30 minutes, 1, 2, and 3 hours in normal adult. The results appeared that Lasix 20mg intravenous injection and 1 hour walking double stimulation is suitable method of PRA stimulation test in out-patient clinic. The Lasix 40mg I.V. and 2 hour walking stimulation test is considered to be suitable method of PRA stimulation test in ward patient. With above study, the following method of PRA study in out-patient clinic is recommended; 1) Overnight fasting and overnight urine collection for urinary sodium measurement 2) Patient should visit hospital in fasting state and take rest for 30 minutes in supine or sitting position and thereafter take blood sample about 5-10ml as out-patient basal PRA. Inject Lasix 20mg intravenously and walk for 1 hour and take blood sample again as double stimulation test. As double stimulation test of PRA for in-patient, Lasix 40mg l.V. and 2 hours walking is recommended. By using above method, the basal PRA in clinic in 16 young normal adults was 2.30+/-1.02(0.70-3.47)ng/ml/h sitting rest and 1.76+/-1.21(0.1-4.03)ng/ml/h in supine rest. In 47 non-hypertensive ward patients who will not have any abnormality in PRA, the 24 hour urinary sodium was average 221mEq and the basal PRA was and the basal PRA was 1.46+/-0.89(0.30-3.75)ng/ml/h. In outpatients with essential hypertension without complication, the average basal PRA was not different from that of normal adult. However male ward-patients with essential hypertension without complication had slightly higher average PRA than normal adult. The distribution of low(2.36ng/ml/h) renin groups in essental hypertension showed higher incidence of high renin group in male ward-patients. But in out-patients with hypertension, the low renin group of patient was high. Relatively low normal value of PRA in this study may be due to high sodium in-take. The higher incidence of high PRA group in essential hypertension of in-patients may be due to the difference of hypertensive status between out-patient and in-patient.

Study on the Conduction Disturbances of Heart in Korean by Electrocardiogram

Since the development of cardiac monitoring, Holter ECG monitoring, His Bundle electrogram and cardiac pacemaker, the cardiac conduction defect has been diagosed more precisely. Also SA block and sick sinus syndrome were well investigated recently. Author reviewed 10,084 cases of electrocardiograms for recent 3 years which were examined at korea University Hospital and analyzed the incidence of conduction defect, type of SA block, conduction defect in myocardial infarction and the relation of SA and AV conduction defect and Q-T(c). There were 5,390 cases of male and 4,694 cases of female with age range of 10 months to more than 80 years. In 60 cases, 24 hour Holter ECG monitoring were also carried out. The data were as follows; 1. There were 568 cases of cardiac conduction defect out of 10,084 cases and the incidence was 5.64% as a whole. Among the conduction defects, there was SA block in 0.36%, AV block in 2.12%(1st degree in 1.86%, Mobitz type I in 0.11%, Mobitz type II in 0.08%, complete block in 0.07%), bundle branck block in 2.52%(RBBB in 2.13%, LBBB in 0.39%), intraventricular conduction defect in 0.20%, left bundle hemiblock in 0.07%, bifascicular block in 0.05%, 1st degree AV block with BBB in 0.18%, W-P-W syndrome in 0.1% and L-G-L syndrome in 0.04%. 2. There were 36 cases of SA block among 10,084 cases(0.36%). In 26 cases, there were one case of Mobitz type I 2nd degree SA block, Mobitz type II in 20 cases, no P wave with nodal escape in 13 cases and 2 cases of transient sinus arrest associated with syncopal attack which were diagnosed by 24 hour Holter ECG monitoring. 3. There were 45 cases of conduction defect in 122 cases of acute or subacute myocardial infarction(36.9%). Among the 45 cases, there were 2 cases of SA block, 15 cases of 1st degree AV block, 2 cases of 2nd degree AV block, 2 cases of complete AV block, 10 cases of RBBB, 3 cases of LBBB, 4 cases of intraventricular conduction defect and 7 cases of left bundle hemiblock. These data showed lower incidence of critical conduction defect such as Mobitz type II and complete AV block in Korea than in United States. 4. The Q-T(c)interval were measured in 207 cases of SA block and AV block without BBB or IVCD. The values of Q-T(c)in cases of conduction defect were within normal limits. In cases of myocardial infarction, there were mild prolongation of Q-T(c)interval, however there was no difference of Q-T(c)interval between infarction with conduction defect and those without conduction defect. There was no correlation between P-R interval prolongation and Q-T(c)interval. These data suggested that the cardiac conduction defect is a specific involvement of conduction system by various causes rather than diffuse myocardial changes.

Effect of Atenolol(Tenormin(R)) on Blood Pressure and Plasma Renin Activity in Essential Hypertension

The effect of Atenolol on the blood pressure were studied in 31 cases of essential hypertension and on the effect of plasma renin activity in 8 cases. There were 8 cases of male with age 49.5(42-70) and 23 cases of female with age 49(35-71) years. 27 cases of 31 cases were untreated hypertensive patients and 4 cases were refractory to hypotensive drugs of diuretics and vasodilators. The Atenolol 50mg once-daily was given to all patients orally for 3 weeks. The blood pressure, heart rate, ECG and symptoms were checked in one week interval. In 8 cases, the plasma renin activity was measured by Dainabot Kit before and after one week medication. The results were as follows: 1. In 27 cases of untreated hypertension, the control blood pressure was 182.9/11.4mmHg in average. The blood pressure decreased in average by 18.3/11mmHg in one week, 23.7/15.9mmHg in two week and 21.5/10.5mmHg in three week. The heart rate also decreased by 7.4/min. in one week, 14.9/min. in two week and 7.8/min. in three week. These data showed considerable reduction of blood pressure and heart rate with 50mg Atenolol once-daily. 2. The basal plasma renin activity after one week medication was reduced by 46% in 8 cases and this data showed considerable reduction regardless control level of basal plasma renin activity. 3. There were considerable blood pressure reduction by adding Atenolol 50mg once-daily to diuretics and vasodilator to which patient's blood pressures were refractory. 4. There was no orthostatic hypotension or serious side effect by Atenolol medication.