Serum Myoglobin as a Biochemical Marker to Rule Out Acute Myocardial Infarction

BACKGROUND: Diagnosis of AMI in the patients presenting with chest pain of an atypical nature or with a nondiagnostic ECG requires the evaluation of certain biochemical markers. Biochemical markers most often used for the early detection of myocardial damage are CK-MBact, troponin, and myoglobin. The clinical value of measuring serum myoglobin was compared to that of troponin and CK-MBact in the patient with acute chest pain syndrome. METHOD: We studied timed, sequential measurements of serum myoglobin, CK-MBact and troponin-T obtained from 72 patients who were admitted for the evaluation of suspected AMI within 12 hours after the chest pain onset. Patients with a history of recent trauma, cardiogenic shock, renal failure, or who had received recent cardiopulmonary resuscitation were excluded. We calculated the sensitivity, specificity, negative predictive value, and positive predictive value. Data were analyzed with the Chi-square test for differences in proportion. A value of p<0.05 was considered statistically significant. RESULT: 1) The mean time from symptom onset to arrival at the emergency department was 3.5+/-0.6 hours. 2) There were no statistical differences in age, sex and risk factors between AMI, angina pectoris and atypical chest pain group. 3) The negative predictive value of myoglobin was significantly higher than those of CK-MBact and troponin-T from 3 to 6 hours after the onset of chest pain. 4) The time to peak of myoglobin level was shorter than those of CK-MBact and troponin-T in AMI patients. CONCLUSION: Within 3 to 6 hours after the onset of symptoms, myoglobin is a better marker than CK-MBact or troponin-T in ruling out AMI for the patient with acute chest pain syndrome.

Segmental Analysis of Thallium-201 Stress Myocardial Perfusion Scanning in Coronary Artery Disease

This study was done to determine the value of thallium-201 stress myocardial perfusion scanning for identifying disease in the individual coronary arteries. Segement analysis of rest and stress myocardial perfusion scanning was performed in 65 subjects who underwent coronary arteriography. Anterolateral wall detects had a sensitivity of 70%, a spectivity of 92%, and a predicitive accuracy of 93.3% for identifying left anterior descending(LAD) coronary artery disease(CAD). Anteroseptal wall defects had a sensitivy of 62.5%, a specificity of 80%, and a predictive accuracy of 83.3% for identifying LAD CAD. Septal wall defects had a sensitivity of 67.5%, a specificity of 92%, and a predictive accuracy of 94.4% for identifying LAD CAD. Inferior wall defects had a sensitivity of 65.4%, a specificity of 89.7%, and a predictive accuracy of 80.9% for identifying right CAD. Posterolateral wall defects had a identifying left circumflex CAD. Thus, although senmental analysis of stress myocardial perfusin scanning can identify LAD CAD with high sensitivity and specificity, only moderate sensitivity and specificity are achieved in identifying right CAD or left circumflex CAD. But stress myocardial perfusion scanning has tendency to identify the most severely ischemic area, use of segmental analysis may be of benefit in the evaluation of patients with ischemic heart disease before or after coronary artery bypass graft and percutaneous transluminal coronary angioplasty.

The Study of Lipoprotein Levels in Angiographically Defined Coronary Artery Disease in Korean Adults

To investigate the discriminative values of different lipid and lipoproteins in the presence and severity of coronary artery disease(CAD), liporotein profiles and other risk factors were measured in 333 patients age 30-69 years who were admitted at Severance Hospital from January 1980 to Agust 1986. The extent of atherosclerosis was quantified by a coronary atheosclerosis score(CAS) based on number and severity of lesions in eight proximal segments of the follows; 1) In age 30-49 and 50-69 groups, there were no significant differences of age, hypertension, smoking, diabetes, obesity to compare with control groups. 2) In age 30-49 group, the extent of CAD was more severe in male patients(1.7+/-0.7 vessel disease) than female(1.3+/-0.6 vessel disease)(P<0.05). But, no significant difference was showed between male(2.0+/-0.9 vessel disease) in age 50-69 group. CAS was significantly increased in male patients(6.1+/-3.7)to compare with female(3.7+/-2.6) in age 30-49 group(P<0.01). But, there was no difference in age 50-69 group. However, stronger liner correlations were demonstrated between the age and CAS in male patients(r=0.227, P<0.005) and in female patients(r=0.317, p<0.05). 3) Total cholesterol(TC), triglyceride(TG), HDL/c, HDL-TC and HDL-C/LDL-C were significantly associated with the presence of CAD in age 30-69 male patients; HoweverTC and LDL-C had disciriminatory value only for age 50-69 female patients. 4)The concentration of TC, LDL/C, HDL-C/TC and HDL_C/LDL-C showed a strong correlation with CAS in male patients, TC and LDL-C in female patents. But, HDL-C had no significant correlation with CAS on both groups. Above data suggest that TC, TG and HDL-C are the significants markers in man and TC and LDL-C on female for presence of CAD. The concentration of TC and LDL-C are related to the severity of CAD in both sexes. Further studies of lipoproteins and risk factors with large population are needed.

Angiographic Findings of Infarct-Related Artery in the Time Course of Myocardial Infarction

We studied 70 cases of transmural myocardial infarction with first attack to look into the coronary anatomy of the infarct-related artery in the time course of infarction and evaluate the left ventricular wall motion according to patency of the infarct-related artery. The following result were obtained. 1) Among 70 cases with transmural myocardial infarction, 47(67.1%) had anterior infarction and 23 (32.9%) inferior infarction. Mean age of the total cases was 52.1+/-10.6 and M:F ratio was 7.8:1. 2) 28 cases were single vessel disease(40.0%), 19 cases were two vessel disease(27.1%), 18 cases werew three vessel disease(25.8%) and 5 cases had insignificant coronary stenosis (7.3%) with 4 cases of normal coronary artery. 3) The total occlusion rate of the infarct-related artery in 70 cases was 48.6%. The total occlusion rate of the 8 cases catheterized within 1 day was 87.5%, that of the 17 cases from 2nd to 15th day 52.9% that of the 23 cases from 16th day to 2nd month 39.1%, that of the 15 cases from 3rd to 12th month 40.0% and that 7 cases from 2nd and 6th year 42.8%. These results suggest that the natural resolution of the infarct-related artery has almost happened within 2 weeks. 4) The left ventricular ejection fraction was higher and the left ventricular end-diastolic pressure was lower in the group with incomplete occulsion of infarct-related artery than in those with complete occulsion, and left ventricular wall motion was better in the group with incomplete occulsion of the infarct-related artery than in those with complete occulsion.

Left Ventricular Function in Coronary Artery Disease with or without Myocardial Infarction

Previous studies showed that in patients with coronary artery disease(CAD), the ejection fraction(EF) response to exercise was often abnormal. Therefore, the fact that EF at rest might be infulence by extent of CAD was implied. So, we studied the relationship between the extent of CAD and the left ventricular function with LVEDP and LVEF measured by area-laength method in 168 patients with significant CAD without myocardial infarction and 111 cases with myocardial infarction. The results are as follows: 1) In 168 cases with significant CAD without myocardial infarction, LVEF in 87 cases with single vessel involvement is significantly higher than in 81 cases with multi-vessel involvement(76.4+/-10.0, 71.3+/-14.9), but LVEF in both group are within normal limits of ours(75.1+/-18.8). LVEDP has no difference between groups. 2) In 111 cases with myocardial infarction, there are no significant difference in LVEDP and LVEF between single vessel group and multi vessel group. But LVEF in both group are significantly lower than normal range of ours. In conclusion, LVEF in the group without myocardial infartion was infulenced by the extent of CAD. But LVEF in the group with myocardial infarction may be influenced by not only the extent of CAD but also infarction site, duration after infarction and collerteral vessels.

A Study on Real-Time Arrhythmia Detection System(II): Part II. Signal Process Algorithm

We designed software system to detect intermittent arrhythmia from the patients automatically. To overcome the difficulties on real-time processing, we used four variavles; heart rate, QS width, morpholigy and axis. Templete generation routine was designed to produce patient's individual normal ECG pattern and store in the computer. The most important point of automatic detection is to discriminate the Q and J point. It is done by linear phase differentiation, the point that five point gradient is within a minimum value of 6Hz curve gradient is defined as Q and J points. The morphology calculation is simplified by simple addition and substraction, making real-time processing by modified cross correlation method. We find that both value of morphology and QS width will be used as a parameter of datermining the abnormalities of ECG signal automatically.

Comparative Study on Stress Electrocardiography and Thallium-201 Stress Myocardial Scintigraphic Imaging in Coronary Artery Disease

To evaluate the diagnostic value of thallium-201 stress myocardial scintigraphic imaging and stress electrocardiography, sensitity, specificity and predicitive value of thallium-201 stress myocardial scintigraphic imaging were compared to simultaneously recorded 12 lead electrocardiography in 17 normal subjects and 30 patients with coronary artery disease who proved by coronary arteriography. The following results were obtained. 1) The mean age was 49.5+/-10.7 years(mean+/-SD)in subjects with normal coronary arteries and 53.1+/-8.8 years in patients with stenotic coronary arteries. 2) Fourteen patients had one-vessel disease, 10 two-vessel disease and 6 three-vessel disease. 3) Sensitivity of thallium myocardial scintigraphic imaging was higher than that of stress electrocardiography(86.7% vs 76.7%). 4) Specificity of both tests was same(70.6% vs 70.6%). 5) Sensitivity of thllium-201 stress myocardial scintigraphic imaging and stress electrocardigraphy in relation to the extent of coronary artery disease showed 78.6% vs 64.3% in one vessel disease, 90% vs 80% in two-vessel disease and 100% vs 100% in three-vessel disease. 6) Predictive value of thallium-201 stress myocardial scintigraphic imaging and stress electrocardiography revealed 83.9% vs 82% in the postive test and 75% vs 63.2% in the negative test. In conclusion, even though thallium-201 stress myocardial scintigraphic imaging was superior to stress electrocardiography in diagnosing coronary artery disease, scintigraphic defects were noted in 5 subjects with normal coronary arteries which could mislead to erroneous diagnosis of coronary artery disease. This point should be taken into consideration in the interpretation of thallium-201 stress myocardial scintigraphic imaging.

Percutaneous Transluminal Coronary Angioplasty(PTCA) of Coronary Artery Stenosis

Since the introduction of PTCA by Gruntzig in 1977, this is now widely used in some subsets of patients with coronary artery disease and is an effective alternative to surgery for many patients. In the 3 years from June 1983 to June 1985, PTCA was attempted in 33 patients with coronary artery disease at the Severance Hospital. There were 26 men and 7 women, whose mean age was 51 years(31-68year). Seven patients had a previous myocardial infarction. Thirty one of 33 patiens presented with chest pain. Twenty four patients had unstable angina and 7 stable angina. the median duration of angina was 5 months(1-120months). 29 had one vessel disease. One had left main disease, 1 two-and 2 three-vessel disease. PTCA was attempted on lesions located in the left anterior descending artery in 26 patients, right coronary artery in1. Successful dilation(stenosis opened by 20% or more of the normal luminal diameter)was achieved in 24 patients(73%). Seventy seven of the stenosis of the LAD and 75% of the RCA was succesfully dilated, whereas PTCA was failed in all 2 patients with a stenosis of the LCX. One patients with a stenosis of the left main artery was succesfully dilated. The mean degree of stenosis was reduced from 77+/-2% to 34+/-2%(P<0.001). The mean pressure gradient was diminished from 53+/-8mmHg to 18+/-6mmHg(P<0.001). Acute coronary occlusion occured in 4 patients(12%). Three of them developed acute myocardial infarction. Emergency coronary bypass operation was done in 2 patients, but one died on the day of operation. Follow-up clinical assessment in the hospital after successful angioplasty indicated freedom from angina in the most of successfully dilated patietns. Eleven patients who underwent successful dilation had basesline and follow-up(within 2 weeks after PTCA) transmill tests. Nine of 11 patients with a positive treadmill test before PTCA obtained negative results after successful angioplasty. Mean exercise duration increased from 316+/-46sec to 601+/-34sec(P<0.001). Eight patients have developed recurrence of angina(recurrence rate;33%) during follow-up period of 3 to 36 months(medial;10 months). In 6 of these cases, restenosis has been documented angiographically within 3 months of dilatation. Four asymptomatic patients have had follow-up angiography. In all patients, the dilated segments was unchanged or improved. Repeat PTCA was attempted in 5 patients with a success rate of 80% without any complications. This initial expierence with PTCA indicates that it is an effective method of relieving coronary stenosis and ischemic symptoms in selected patients. But it carries an inherent risk of serious complications. Also restenosis is a persistent problem with PTCA. Repeat PTCA can be done with a high success and a low complication rate.

Development and Functional Significance of the Coronary Collateral Circulation in Coronary Artery Disease

Since recognition of coronary arterial clloateral circulation in living patients has been made possible by coronary arteriography, controversy has existed about the functional importance of these vessel and their ability to protect the myocardium against ischemia. The coronary arteriograms and left ventriculograms of 279 consecutive patients were reviewed. All had at least 50% diameter reduction of 1 or more major coronary arteries. In 94 patients(111 arteries), at least 1 major branch was totally occluded. Collateral circulation was seen in 85 of 111(76.6%) totally occlued arteries versus 22 of 107(20.6%) with > or =90% but <100% stenosis(P<0.01). No artery with <90% stenosis(254 arteries) recieved angiographically detectable collateral vessels. An analysis was made of the relation between left ventricular segmental wall motion and the quality of collateral circulation in 68 totally occluded arteries among 60 patients with myocardial infarction(Group 1) and in 43 totally occluded arteries among 34 patients without prior myocardial infarction(Group 2). Good collateral vessels went to 62.8% of Group 2, but 38.8% of Group 1(P<0.05). LV contraction was abnormal in all Group 1 patients with good collateral circulation. Of 27 with good collateral circulation in Group 2, LV contraction was normal in 59.3% and abnormal in 40.7%. But there was no statistically significant difference between the effect of good or poor collateral circulation in LV wall motion in each Group. Also we have studied the frequency of collateral circulation appearance in 34 patients, in whom the date of symptom onset of transmural infarction was definitely documented. The presence of collateral vessels was significantly higher in the patients studied 1-15 day period after symptom onset vs those studied within 1 day(77.8% vs 14.3%, P<0.05). but there was no significant differance in the apperance of collaterals in the patients studied in the 1-15 day vs the 15 day-2 month, and vs the 2-36 month period(77.85, 66.7% and 66.7%, NS). These observation indicate that collateral circulation cannot be seen angiographically unless there is total or near-total occlusion, and that the pressence of good collaterals may play a patrial role in preserving myocardial function and preventing myocardial infarction. The development of collaterals in myocardial infarction seems to be occurred within 15 days after the symptom onset of transmural infarction. But any benefits can not be expected from newly developed collateral circulation after myocardial infarction.

Two Cases of Pulmonic Valvular Vegetation and Pulmonary Infarction Associated with VSD

Bacterial endocarditis is a disease with protean manifestations whose presentation has recently changed greatly. Right-sided endocarditis associated with congenital heart lesions is now relatively less common. Patients with ventricular septal defect are at risk for right-sided endocarditis, but its incidence is low in children and adolescents. The organism is frequently a staphylococcus and the clinical course is dominated by septic pulmonary infarction and septicemia. We reported two cases of pulmonic vegetation and pulmonary infarction associated VSD with brief review of literature.

A Case of Supravalvular and Valvular Aortic Stenosis

Supravalvular aortic stenosis may be defined as an obstructive congenital deformity of the ascending aorta which originates just distal to the level of the origins of the coronary arteries. It may be localized or diffuse, and includes a wide spectrum of pathologic changes. A 16 years old school boy was admitted because of exertional dyspnea for 6 years. Clinical diagnosis of supravalvular and valvular aortic stenosis with bicuspid aortic valves and myocardial hypertrophy was made by echocardiography and angiocardiography. Surgical correction was performed successfully. We presented a case of supravalvular and valvular aortic stenosis with a review of literatures.

2 Cases of Dual Left Anterior Descending Coronary Artery

"Dual LAD" was defined as the early bifurcation of the proximal LAD into two vessels : a short LAD which remained in the anterior interventricular sulcus and does not reach the apex, and a long LAD which leaves the anterior interventricular sulcus only to return to the distal sulcus and continue to the apex. Recognition of "Dual LAD" is essential to prevent errors of interpretation of the coronary arteriogram and for planning of optimal surgical therapy. We report 2 cases of "Dual LAD" with the review of the literatures.