The Effects of L-thyroxine Treatment on QT Dispersion in Primary Hypothyroidism

Hypothyroidism has various cardiovascular manifestation and exhibits electrocardiographic change. The QT dispersion on surface ECG reflects regional variations in myocardial repolarization. The effect of L-thyroxine treatment on ECG parameters, such as QT dispersion, in patients with primary hypothyroidism were investigated. This study involved 18 patients (3 men, 15 women, ages: 48+/-18 yr) with primary hypothyroidism. All patients were checked with a standard 12-lead ECG before and after L-thyroxine treatment. Various ECG parameters were then measured twice. The mean L-thyroxine treatment duration was 22+/-2.7 months. The mean thyroid-stimulating hormone levels of patients before and after therapy were 40.2+/-29.8 microU/mL, 3.6+/-4.6 microU/mL (p<0.001) and free-T4 levels were 0.44+/-0.38 ng/dL, 1.51+/-0.39 ng/dL (p<0.001). After L-thyroxine treatment, QT interval (395+/-42 vs. 380+/-24 msec, p<0.05), QTc interval (434+/-32 vs. 417+/-23 msec, p<0.05), QT dispersion (45+/-23 vs. 30+/-13 msec, p=0.008), QTc dispersion (49+/-23 vs. 32+/-14 msec, p=0.005) significantly decreased. There were no significant changes in the PR and RR intervals, as well as the QRS duration. Our findings suggest that the thyroid hormone affects ventricular inhomogenicity, and that L-thyroxine replacement therapy may reduce malignant ventricular arrhythmia and sudden cardiac death in primary hypothyroidism.

A case of Sheehan's syndrome presented by recurrent ventricular tachycardia / 대한내과학회지

Electrocardiographic abnormalities commonly associated with hypopituitarism are low QRS voltage, ST-segment depression, inverted T waves and a prolonged QT interval. Although the mechanism remains unclear, glucocorticoid therapy, an intracelluar-extracellular electrolyte imbalance of myocytes, and histopathological changes in the myocardium are thought to play a role in this disorder. We discribe a 64 year old woman with recurrent ventricular tachycardia associated with QT prolongation in Sheehan's syndrome. Ventricualr tachycardia was treated by lidocain and direct current cardioversion. Sheehan's syndrome was confirmed by past history, anterior pituirary stimulation test and brain MRI showed empty sella. After hormone replacement treatment, inverted T waves and prolonged QT interval was normalized and ventricular tachycardia did not recur.

A case of thyrotoxic periodic paralysis associated with rhabdomyolysis / 대한내과학회지

Hyperthyroidism has been associated with changes in muscle function such as thyrotoxic myopathy, thyrotoxic periodic paralysis and thyroid opthalomopathy, but rarely rhabdomyolysis. Usually serum creatinine kinase is either normal or low in hyperthyroidism. Only 3 reports described association between rhabdomyolysis and hyperthyroidism, no previous literatures have thyrotoxic periodic paralysis associated rhabdomyolysis. Patients with hypokalemic periodic paralysis sometimes elevated serum muscle protein during recovery from paralytic attack, but the mechanism was not well known. We report a patient who presented with clinical feature of thyrotoxic periodic paralysis and increasing serum CK, myoglobin during recovery from paralysis.

Electrocardiographic Changes after Hormone Replacement Treatment in Patients with Sheehan's Syndrome / 대한내분비학회지

BACKGROUND: Electrocardiographic abnormalities were studied to find if they were reversible during adequate hormonal treatment and to investigate regional inhomogenicity of ventricular repolarization in patients with Sheehan's syndrome. METHODS: Eleven women with Sheehan syndrome, who treated with prednisolone and levothyroxine, were the subjects of this study. Before and after hormonal replacement, the plasma thyroxine, cortisol and resting standard EKG were checked RESULTS: The most frequent electrocardiographic finding was inversion or flattening of the T waves, which occurred in 10 patients, with QT prolongation (7 patients), ST depression (2 patients) being the other findings. After prednisolone and levothyroxine replacement, the T wave abnormalities were normalized in 8 patients (80%) and the ST depression all patients. The QT (437 27 msec vs. 379 29 msec, p<0.05) and QTc intervals (478 80 msec vs 403 73 msec, p<0.005) were shortened by hormone replacement. CONCLUSION: High incidences of electrocardiographic abnormalities, including T wave inversion or flattening, QT prolongation and ST depression, were noted in patients with Sheehan's syndrome. The majority of these abnormalities recovered due to hormone replacement. The QT and QTc interval values were significantly shortened after treatment. Therefore, the regional inhomogenicity of ventricular repolarization may recover with hormone replacement

The neointimal hyperplasia effect of erythropoietin on carotid artery injury model of rat / 대한내과학회지

BACKGROUN: Neointimal hyperplasia is major cause of instent restenosis in coronary artery and stenosis in arteriovenous fisula for hemodialysis. Erythropoietin is known to show proliferative effect on vascular smooth muscle cells in vitro study, but there is few in vivo study. This study investigated the effect of erythropoietin given subcutaneously to injured carotid arteries of rats on neointimal hyperplasia. METHODS: Sprague-Dawley rat underwent common carotid artery (CCA) balloon injury. Erythropoietin was given subcutaneously to balloon-injured rats (n=6) in 100 U/Kg/week by dividing three times. The control group (n=6) was treated with normal saline only. Two weeks later, the lumen and the neointimal area were obtained and compaired. Actively proliferating cells of neointimal area were observed by microscopy using PCNA staining method. RESULTS: Luminal area was 0.233 +/- 0.073 mm2, 0.112 +/- 0.047 mm2 in the control and the erythropoietin treated group respectively. The area was significantly smaller in the treatment group (p<0.05). Neointimal area and neointimal area/medial area ratio were 0.148 +/- 0.029 mm2, 0.226 +/- 0.056 mm2 and 1.169 +/- 0.146 min, 1.953 +/- 0.465 min in the control and the erythropoietin treated group respectively (p<0.05), but no significant difference was observed in medial area between the control and the erythropoietin treated group. Actively proliferating cells of neointimal area were more commonly observed in erythropoietin treated group. CONCLUSION: Erythropoietin increases neointimal cell proliferation in the rat carotid artery injury model. So, erythropoietin treatment may contributes to the development of arteriovenous fistula stenosis caused by neointimal hyperplasia but, further studies are required to elucidate the mechanism and the effect of erythropoietin at various time and dose in neointimal hyperplasia.

A Case of Primary Pericardial Undifferentiated Sarcoma

Primary pericardial sarcomas are extremely rare. The authors report a case of a 46-yr-old woman in whom a large mediastinal mass was discovered. The patient presented with cough, dyspnea, and orthopnea. Diagnostic investigations, such as echocardiography, computed tomography, and exploratory thoracotomy provided the evidence of a large mass in the mediastinum, attached by a broad base to the superior portion of the pericardium. A excisional biopsy was performed, and histologic examination of a biopsy specimen showed undifferentiated sarcoma. However, the complete removal of the mass was impossible due to adhesion to the adjacent great vessels. After the completion of the chemotherapy the patient was completely asymptomatic. However, follow-up transesophageal echocardiography showed a residual 3x4 cm-sized mass. The patient received the radiotherapy with a total dose of 55 Gy over 6 weeks. At present, there is no evidence of disease progression.

Comparison between Echocardiography and Gated SPECT in the Assessment of Left Ventricular Wall Motion in Patients with Acute Myocardial Infarction

BACKGROUND AND OBJECTIVES: Assessment of the regional left ventricular function provides valuable diagnostic and prognostic information of patients with coronary artery disease. The aim of the study was to analyze the agreement between wall motion scores, derived by gated single photon emission computed tomography (SPECT) and echocardiography (Echo) in myocardial infarction patients with a perfusion defect. SUBJECTS AND METHODS: We studied the regional wall motion in 81 patients with an acute myocardial infarction, who underwent adenosine stress gated SPECT and Echo. Echo was performed in all the patients immediately prior to, or following, gated SPECT. The regional wall motion was evaluated by both modalities, and scored using a 16-segment model with a 4-point scoring system: 1=normal, 2=mild and moderate hypokinesia, 3=severe hypokinesia, 4=akinesia or dyskinesia. RESULTS: There was a high agreement in the left ventricular regional wall motion scores between the gated SPECT and the Echo of 84.2% of segments (1091/1296 segments, k=0.76, p<0.0001). The agreement in the regional wall motion scores between the two modalities decreased significantly along the longitudinal axis of the left ventricle from 92.9% (301/324, k=0.89, p<0.0001) at the apex, 84.6% (411/486, k=0.77, p<0.0001) at the mid point, to 77.9% (379/486, k=0.65, p<0.0001) at the basal segments (p<0.0001). Also, the agreement based on the degree of myocardial perfusion was 86.6% for segments with normal, or mild hypoperfusion, and 82.6% with moderate to severe hypoperfusion (p=0.072). CONCLUSION: The gated SPECT had a good agreement with the Echo for the assessment of the left ventricular regional wall motion in patients with an acute myocardial infarction. These results support the clinical use of gated SPECT.

A Dieulafoy's Lesion of the Rectum Treated by Endoscopic Band Ligation: A case report / 대한소화기내시경학회지

The Dieulafoy's lesion is an unusual cause of gastrointestinal hemorrhage that results from the erosion of abnormally large submucosal artery. The lesion is usually located in the stomach, although it may occur anywhere in the gastrointestinal tract. Lower GI bleeding from Dieulafoy- like lesion of rectum is very rare. We describe one patient with extragastric Dieulafoy's disease, in the rectum. Diagnosis was made by endoscopy. Recently, endoscopy is important in the treatment of Dieulafoy-like lesion of rectum including epinephrine injection and coagulation therapy. We treated with the endoscopic management using ligation technique. We report a case that the 65-year old women had a extragastric Dieulafoy's lesion on the rectum, treated by endoscopic ligation with O-ring.

A Case of Primary Cardiac Amyloidosis

Amyloidosis is not a single disease entity but a term applied to a complex of disorders associated with deposition of insoluble fibrillar proteins in virtually pure form in various tissues of the body. This disease is encountered sometimes in America or Europe, but rarely in Korea. We had experienced one case of primary cardiac amyloidosis who was admitted to Won Kwang University Hospital due to dyspnea on exertion. This cardiac amyloidosis was confirmed by echocardiogram and endomyocardial biopsy with congo-red stain. We will report a case and review the pertinent medical literature.