A Case of Pure Red Cell Aplasia Associated with Invasive Thymoma / 대한혈액학회지

Thymoma has been associated with a variety of diseases, including myasthenia gravis, pure red cell aplasia (PRCA), hypogammaglobulinemia, and other abnormal immune and endocrine disorders. Herein we report a case of PRCA associated with invasive thymoma in a 65-year-old man. In spite of total thymectomy and irradiation to the mediastinum, no significant response was observed. The mechanisms and management of PRCA associated with invasive thymoma are reviewed.

Adrenergic Effects on the Cardiac Damage by Oxygen Free Radicals

BACKGROUND: It is now well known that oxygen free radicals act as mediators of cellular injury in many cardiovascular diseases. Although some evidences have been presented for an altered number of adrenergic receptors in heart disease, a detailed examination of the interaction of free radicals with cardiac adrenergic receptors has little been carried out. METHODS: This study is therefore undertaken to examine the influences of adrenergic blocking agents(propranolol, prazosin) and cyclooxygenase inhibitor(aspirin) on the cardiac damage by oxygen free radicals. Ischemic condition of the isolated rat heart was made by Langendorff preparation, and then measured superoxide dismutase(SOD), lactate dehydrogenase(LDH) released in the perfusate, and malondialdhyde(MDA) concentration in the cardiac tissue. RESULTS: We obtained the results that increased SOD activity and tendency of decreased LDH activity by the pretreatment of propranolol, prazosin, and aspirin in cardiac ischemic-reperfusion injury. Those effects were more predominant in adriamycin treated group comparing with not treated group. CONCLUSION: Adrenergic blocking agent, propranolol, prazosin, and aspirin seem to have some protective effect on the reperfusion injury of the heart.

Risk Factor of Left Atrial Thrombi after Valve Replacement

BACKGROUND: Thromboembolism is the major complication in patients with the insertion of cardiac prosthetic valves. The purpose of this study is evaluate the risk factors about the formation of left atrial thrombi after cardiac valve replacement. METHOD: Transesophageal(TEE) and transthoracic echocardiography(TTE) were done to evaluate postoperative cardiac condition in 98 patients with cardiac prosthetic valves from Jan. 1991 to Oct 1991. Several clinical and echocardiographic parameters were analyzied to evaluate the relationship with the formation of left atrial thrombi. RESULT: In univariate analysis, important factors related to the formation of left atrial thrombi are type of operation (p=0.027), postoperative left ventricular function(p=0.003), preoperative(p=0.037) and postoperative systolic ventricular size(p=0.024). However, in multivariate analysis postoperative left ventricular size(p=0.017), presence of previous thrombi(p=0.014), preoperative left atrial size(p=0.014) and postoperative left atrial size(p=0.014) are significant factors. CONCLUSION: Patients with high risk and low risk for the formation of left atrial thrombi after valve replacement can be identified by readily available clinical and echocardiographic variables.

Circadian variation in acute myocardial infarction

BACKGROUND: TAn increased occurrence of morning time acute myocardial infarction(AMI) based on subjective self-reports and objective confirmation has been reported in the USA and Europe. We tried to see if the same circadian pattern is found among Korea patients in the regard. We have also studied how various modifying factors such as age, gender, history of congestive heart failure, previous angina pectoris, hypertension and smoking may affect the circadian pattern. METHODS: The onset of chest pain was studied in 471 patients with AMI admitted to four teaching hospitals in Taegu. Korea. We categorized the patients according to the modifying factors described above. RESULTS: The patients with AMI indeed showed bimodal variation at the onset of myocardial infarction with the primary peak between 6 A.M. and 12 noon. The frequency of the onset of pain occurred during this 6 hour period was 1.8 times higher than the average of the remaining period(p<0.001). The secondary peak occurring in the evening was barely noticeable. On the other hand. the sub-group(n=96) with a history of congestive heart failure demonstrated its peak(30%) in the evening(6 pm~12 midnight) and the sub-group with a history of hypertension(n=177) demonstrated its peak(37%) in the afternoon(12noon-6P.M.). However. the rest of the sub-groups smokers, patients with previous angina and patients over the age of 70 revealed typical circadian rhythm with a pronounced primary morning peak. CONCLUSIONS: This study clearly showed that Korean patients with AMI revealed a remarkably similar circadian pattern, primary morning peak of onset of myocardial infarction and that the marked differences in diurnal patterns of myocardial infarction onset occur in sub-groups of patients with modifying factors, particularly previous congestive heart failure and hypertension.

Relationship between the blood flow patterns of left atrial appendage(LAA) with spontaneous contrast(SC) echogenecity and thrombi in LAA

BACKGROUND: Patients with sinus rhythm, the left atrial appendage(LAA) appeared as a vigorously contracting structure and the blood flow patterns of LAA showed biphasic configuration. However, patients with AF rhythm the blood flow showed irregular or no configuration in doppler echocardiographic study. The purpose of this study is to evaluate relationship between the blood flow patterns of LAA with the presence of spontaneous contrast(SC) and thrombi in LAA. METHODS: We performed TEE and TTE simultaneously to 58 consecutive patients who had native mitral valve disease or mitral prosthesis. Spontaneous contrast(SC) and the presence and location of LAA thrombi were evaluated during TEE and left atrial dimension(LAD) & ejection fraction(EF) were evaluated during TTE. We divided the whole subjects into three groups according to the blood flow patterns ; regular pattern(Group 1), irregular pattern(Group 2), no flow pattern(Group 3). RESULTS: 1) Blood flow within the left atrial appendage is divided with three groups among of them, atrial fibrillation have two blood flow patterns. 2) Peak prositive & negative flow velocity within LAA in AF rhythm groups were slower than normal sinus rhythm group.(p<0.01) 3) Left atrial dimension in group 3 is significantly larger than others groups.(p<0.01) 4) Spontaneous contrast(SC) with LAA could be detected in 2(6.8%) of the 29 patients of group 1, 6(31.5%) of the 19 patients of group 2, 10(100%) of the 10 patients of group 3. Incidence of SC within LAA in group 3 is significantly higher than others groups. 5) LAA thrombi could be detected in 1(3.4%) of the 29 patients of group 1, 1(5.2%) of the 19 patients of group 2, 3(30%) of the 10 patients of group 3. Incidence of LAA thrombi is significangly higher than other groups. CONCLUSIONS: We can suggest that blood flow within LAA is divided into three groups according to the blood flow patterns, and spontaneous contrast and thrombi in LAA were closely related with the blood flow pattern.

Evaluation of functional regurgitation flow in patients with clinically normal mitral prosthesis by transesophageal echocardiography

BACKGROUND: In vitro study, normal cardiac prosthetic valve has functional regurgitation due to structural characteristics of prosthetic valve. To evaluate functional regurgitant characteristics of prosthetic valves, we examined patients who had clinically normal mitral prosthesis. METHODS: Transesophageal two-dimensional and color doppler echocardiography were performed to 25 patients who had the clinically normal mitral prosthesis. RESULTS: Seven patients had the mitral bioprosthesis and 18 patients had the mitral mechanical prosthesis. Regurgitation was found in 4 patients(57%) with bioprosthetic valve, and the pattern of regurgitation was central in three patients and unilateral in one patient. But regurgitation was detected in 17 patients(94%) with mechanical prosthesis, and the pattern of regurgitation was bilateral in twelve patients, unilateral in four patients and central in one patient(p=0.0035). The length of regurgitant jets were 22.00+/-6.73(mm) in bioprosthetic valve and 28.65+/-7.33(mm) in mechanical valve. The regurgitant jets were detected in systolic period in most of patients. But in 4 patients who had tachycardia during TEE, regurgitation was detected in systolic and early diastolic period. CONCLUSION: Regurgitation was found in clinically normal cardiac prosthetic valves by TEE. These findings may be useful to differentiate between normal and abnormal cardiac prosthesis.

Four Cases of Dissecting Aortic Aneurysms Diagnosed by Transesophageal Echocardiography

BACKGROUND: The prompt and accurate diagnosis of acute aortic dissection is decisive for the prognosis of the patient, since an effective surgical and medical therapy can improve the high rate of mortality due to this pathology. Among the various diagnostic methods, transesophageal echocardiography can provide a rapid and accurate method of diagnosing and evaluating dissecting aortic aneurysm and permits prompt initiation of appropriate treatment. Thus we performed transesophageal echocardiography in patients supected to dissecting aortic aneurysm, as a preliminary examination, and now we reported the result. METHODS: We have studied 4 case of dissecting aortic aneurysms among the patient received examination of cardiovascular system by transesophageal echocardiography, since January 1991 at Keimyung University hospital. In these 4 cases, 3 cases had CT scan, 2 cases had MRI scan, and all cases had transthoracic echocardiography simultaneously as a adjuvant diagnostic method. RESULTS: All 4 cases could be promptly and accuratoly diagnosed and typed by transesophageal echocardiography. As a consequence, patients could receive the early medical treatment and good clinical results. CONCLUSION: Transesophageal echocardiography is fast, inexpensive and accurate method in diagnosis of dissecting aortic aneurysm. So we recommend transesophageal echocardiography, as a preliminary examination in case of suspecting dissecting aortic aneurysm.

The Usefulness of Exercise Stress Echocardiography in Diagnosis of Coronary Artery Disease

BACKGROUND: To evaluate the usefulness of exercise echocardiography in diagnosis of coronary artery disease and to compare it with exercise ECG test. METHOD: We performed exercise test in 48 patients who suffered from angina-like chest pain, according to the modified Bruce protocol. During exercise, we observed the ECG changes and recored the images of left ventricular wall motion before and after exercise on the video tape. The echocardiogram were digitally stored and displayed in a format that allowed simultaneous analysis of rest and stress images. Newly developed left ventricular wall motion abnormalities were determined as positive findings. RESULTS: The feasibility of exercise echocardiography was 75%. The sensitivity and specificity fo exercise ECG test was 67% and 89%. The sensitivity and specificity of exercise echocardiography was 85% and 100%. The sensitivity of ECG and echocardiography was 50%(7 of 14) and 78.6%(11 of 14) in those with one-vessle disease and 84.6%(11 of 13) and 92.3%(12 fo 13) in those with multi-vessle disease. CONCLUSION: Exercise stress echocardiography was very usefull method for detecting the coronary artery disease especially in single vessle disease. And it had much higher accuracy than the stress ECG test.

Clinical Usefulness of Transesophageal Echocardiography for Detection of LA Thrombi and Significance of Left Atrial Spontaneous Contrast

BACKGROUND: To evaluate the efficacy of transesophageal echocardiography(TEE) to detect left atrial thrombi(LAT) and to investigate the clinical and echocardiography parameters which related with LAT. METHOD: We performed TEE and TTE simultaneously to 98 consecutive patients who had native mital valve disease or mital prosthesis as usual method. We examined the presence and location of LAT and spontaneous contrast(SC) in TEE and measured left atrial dimension(LAD), ejection fraction(EF), mital valve area(MVA) in TTE. Cardiac rhythm, history of anticoagulation and systemic embolization were also reviewed. We compared such parameters in LAT positive/negative groups and SC positive/negative groups. RESULTS: 1) In TEE, we detected 26 cases of LAT, among them seventeen cases : left atrial appendage(LAA) thrombi, 3 cases : combined LA and LAA thrombi, 6 cases : LA thrombi. In TTE, six cases showed LAT but we couldn't detect LAA thrombi. The difference between two methods was statistically significant(p<0.05). 2) LAT positive group showed larger LAD, lower EF, and higher prevalence of AF, systemic embolization, and LAT than negative groups(p<0.01). 3) SC positive group showed larger LAD, lower EF, higher prevalence of AF, systemic embolization LAT than SC negative groups(p<0.05). 4) In multiple discriminant analysis, the history of systemic embolization was most important factor which can suspect LAT(Wilk's Lambda:0.77152. p<0.0001). SC, EF, presence of AF, LAD, anticoagulation therapy. MVR were also statistically valuable factors in order. The hit ratio of this analysis was 86.84%. CONCLUSION: We can suggest that TEE is very useful method to detect LAT than TTE, and the spontaneous contrast was very important factor which can suggest LAT and systemic embolization in mitral valve disease.

Pulmonary Venous Flow Pattern by Transesophageal Echocardiography in Healthy Young Adults

BACKGROUND: Although a number of indices of diastolic function based on transmitral flow have been proposed, no single factor seems to be adequate for seperating patients with normal from with abnormal diastolic functions. Pulsed Doppler echocardiography of pulmonary venous flow(PVF) is another non-invasive method to evaluate left ventricular diastolic performance. The purpose of this study is to evaluate the normal PVF pattern by TEE. METHOD: We performed pulsed-wave Doppler studies of the PVF and of the mitral flow by transesophageal-(TEE) and transthoracic echocardiography(TTE) in a healthy young adults. RESULTS: In TEE, all sublects showed four phases of the PVE pattern ; two antewgrade systolic phase(early and late : SE and SL), one antewgrade diastolic phase(D) and one retrograde diastolic phase(A). In TTE, there were three phases of the PVF pattern ; two antewgrade phase(systolic, diastolic) and one retrograde diastolic phase but we couldn't find out early systolic phase flow. Peak velocity of each phase of PVF was as follows:SE was 48.9+/-14.1cm/sec, SL was 56.3+/-16.1cm/sec, D was 52.6+/-14.9cm/sec. The timing of SL flow was correlated significantly with that of peak aortic flow(r=0.42, p=<0.01), while the timing of D flow and that of A flow were correlated significntly with timing of mitral E peak and A peak, respectively(r=0.84, p<0.01 ; r=0.80, p<0.01). CONCLUSIONS: In the young normal subject, PVF showed four phase of flow pattern and could be easily obtained by TEE. Furthermore it may be used for evaluation of left ventricular function.