Predictors of Neurodevelopmental Outcomes in Newborns Undergoing Hypothermia Therapy

PURPOSE: This study aimed to identify the early predictors of neurodevelopmental outcomes in infants undergoing therapeutic hypothermia for neonatal hypoxic ischemic encephalopathy. METHODS: The medical records of 24 neonates who underwent hypothermia therapy for hypoxic ischemic encephalopathy at the neonatal intensive care unit of Yeouido St. Mary's Hospital of the Catholic University of Korea between August 2013 and May 2016 were reviewed. Patients were divided into two groups according to their neurological outcome at the age of 18 to 24 months: a normal group (n=14), which included patients with normal neurological function, and an abnormal group (n=10), which included patients with neurological deficits. The clinical characteristics, clinical outcomes, and laboratory findings before and after hypothermia treatment were compared between the groups. RESULTS: There were no significant differences in the demographic characteristics between the two groups. With regard to clinical outcomes, only brain magnetic resonance imaging (MRI) findings showed significant differences between the normal and abnormal groups (21.4% vs. 100.0%, P 0.05). CONCLUSION: The presence of abnormal lesions on MRI was the most useful predictor of poor neurodevelopmental outcome in infants treated with therapeutic hypothermia after perinatal asphyxia.

Perinatal Factors Associated with the Preterm Thyroid Screening Test / 대한주산의학회잡지

PURPOSE: The aim of this study was to evaluate the usefulness of thyroid function screening in preterm infants and the relation between thyroid hormone level, perinatal environment, and clinical presentation after preterm birth. METHODS: We retrospectively evaluated 46 preterm infants from March 2013 to December 2014, who had been screened for congenital hypothyroidism during the 1st week with thyroid stimulating hormone (TSH), triiodothyronine (T3) and free thyroxine (fT4) measured by the radioimmunoassay method. The effects of pregnancy associated maternal factors, gestational age, growth parameters, Apgar score, 1st meconium passage time, respiratory distress syndrome and apnea on thyroid hormone levels were assessed by Mann-Whitney U-test and multiple linear regression analysis. RESULTS: With advancing gestational age, T3 and fT4 displayed a tendency to increase. FT4 showed a positive correlation pattern with antenatal steroid therapy, corrected gestational age at examination and a negative correlation pattern with 1st meconium passage time and apnea (P<0.05). TSH displayed a positive correlation pattern with 1st meconium passage time, 5-minute Apgar score and a negative correlation pattern with sampling age (P<0.05). CONCLUSION: In the preterm period, both fT4 and TSH seems to correlate significantly with various perinatal factors and clinical presentation. We recommend that early fT4 screening should be included in the screening for hypothyroidism in preterm infants.

Perinatal Factors Associated with the Preterm Thyroid Screening Test / 대한주산의학회잡지

PURPOSE: The aim of this study was to evaluate the usefulness of thyroid function screening in preterm infants and the relation between thyroid hormone level, perinatal environment, and clinical presentation after preterm birth. METHODS: We retrospectively evaluated 46 preterm infants from March 2013 to December 2014, who had been screened for congenital hypothyroidism during the 1st week with thyroid stimulating hormone (TSH), triiodothyronine (T3) and free thyroxine (fT4) measured by the radioimmunoassay method. The effects of pregnancy associated maternal factors, gestational age, growth parameters, Apgar score, 1st meconium passage time, respiratory distress syndrome and apnea on thyroid hormone levels were assessed by Mann-Whitney U-test and multiple linear regression analysis. RESULTS: With advancing gestational age, T3 and fT4 displayed a tendency to increase. FT4 showed a positive correlation pattern with antenatal steroid therapy, corrected gestational age at examination and a negative correlation pattern with 1st meconium passage time and apnea (P<0.05). TSH displayed a positive correlation pattern with 1st meconium passage time, 5-minute Apgar score and a negative correlation pattern with sampling age (P<0.05). CONCLUSION: In the preterm period, both fT4 and TSH seems to correlate significantly with various perinatal factors and clinical presentation. We recommend that early fT4 screening should be included in the screening for hypothyroidism in preterm infants.

Presentation Time of Necrotizing Enterocolitis Diagnosed by Sonography according to Gestational Age

PURPOSE: In this single center study, we assessed the timing of presentation of necrotizing enterocolitis (NEC) diagnosed by sonography according to the gestational age. METHODS: We retrospectively reviewed the medical records of 49 newborn patients who were diagnosed with NEC (modified Bell's stage II and higher according to abdominal sonography and simple abdominal radiography) and were admitted to the neonatal intensive care unit of St. Mary's Hospital between January 2008 and December 2012. Infants were grouped according to their gestational age (GA): Group I (GA or =37 weeks); early-onset NEC was considered when NEC developed at or =14 days of age. RESULTS: The number of infants in each group were: Group I (n = 16), Group II (n = 20), Group III (n = 11), and Group IV (n = 2). The mean age at diagnosis of NEC was: Group I (31.6 days), Group II (15.9 days), Group III (11.0 days), and Group IV (2.0 days). Early-onset NEC developed at a mean of 5.5 days of age, whereas late-onset NEC developed at a mean of 36.1 days of age. CONCLUSION: Based on early sonographic diagnosis, infants with lower gestational ages developed NEC at a more advanced postnatal age as compared to more mature infants. However, further studies are needed to understand the etiology of this disease process.

Neonatal Seizures in Preterm Infants / 대한소아신경학회지

PURPOSE: Neonatal seizures are the most prominent feature of neonatal neurologic dysfunction, and the lifespan risk for seizures is highest in the neonatal period, especially in preterm infants. This study was aimed to find and analyze the risk factors and clinical profiles of seizures in preterm infants. METHODS: Sixteen cases of preterms with seizures were retrospectively reviewed between Mar. 2009 and Feb. 2012. RESULTS: The average gestational age was 30.3+/-4.1 weeks and 11 patients (68.7%) experienced seizures within 1 week after the birth. Eight cases (50%) had a perinatal asphyxia during the delivery and 7 cases (43.8%) had a history of perinatal maternal illness. Various types of seizures were observed of which subtle seizures were the most common (50%). Electroecephalographies were performed in 12 cases, which showed abnormal findings in 9 cases (75%). Neuroimaging studies were performed in 16 cases and showed abnormal findings in 10 cases (62.5%). Thirteen patients were discharged in the improved state and 3 patients expired. Eight cases had normal outcome, while 3 cases showed developmental delay. Prognosis was unknown in 2 cases due to follow up loss. CONCLUSION: Neonatal asphyxia is the most important risk factor. Furthermore, infants with a history of perinatal maternal illness appear to be at risk for neonatal seizures. EEG is a sensitive method for assessing seizure activity and prognosis. Monitoring high risk infants with asphyxia and a history of perinatal maternal illness, and early postnatal tracing with EEG is required to detect and manage high risk preterms.

Predictors of successful catheter ablation of AV nodal reentrant tachycardia / 대한내과학회지

Catheter ablation of the AV nodal slow pathway using radiofrequency (RF) energy has been established as the first-line curative therapeutic modality of recurrent symptomatic AV nodal reentrant tachycardia (AVNRT). In contrast to catheter ablation of the AV bypass tract, there was no useful marker to localize succesful site of the pathway. This study was performed to determine predictors of successful catheter ablation of the AV nodal slow pathway in patients with AVNRT. METHODS: Forty patients (18 men, 22 women; 47.9+/-13.3 years) with AVNRT undergoing successful catheter ablation of the AV nodal slow pathway were included in this study, in which 217 attempts were tried to ablate the AV nodal slow pathway. Characteristics of local atrial electrogram, anatomical site at each attempt, junctional rhythm during RF delivery were analyzed (40 successful, 177 failed). Maximum difference and duration of atrial electrograms were measured and local atrial electrograms were classified into 5 types (A1, A2, B1, B2 and C type) according to the type and the degree of fragmentation. Finally, the occurrence of junctional rhythm during RF discharge and its onset time were compared between successful and failed attempts. RESULTS: There was no significant difference in the maximum difference of amplitude and duration of atrial electrograms between successful and failed attempts. The success rate in each type of atrial electrogram was significantly different. And, the success rate in non-C type atrial electrograms (A1, A2, B1, and B2) was significantly higher than that in type C atrial electrograms (25.0% vs 10.3%, p<0.01). No significant difference was noted in success rates according to attempted sites. Junctional rhythms during radiofrequency application occured significantly more frequent in successful attempts than in failed attempts (87.5% vs 47.5%, p<0.001). The time to onset of junctional rhythm was not different between successful and failed attempts (5.2+/-4.9 sec vs 6.1+/-5.5 sec). CONCLUSION: Fragmented local atrial electrogram and junctional rhythm during RF energy delivery may be used to predict successful catheter ablation of AVNRT. It is recommended that RF energy should be applied to the site where fragmented atrial electrogram is recorded and terminated if junctional rhythm does not develop within 15 seconds after starting RF energy delivery.

Predictors of successful catheter ablation of AV nodal reentrant tachycardia / 대한내과학회지

Catheter ablation of the AV nodal slow pathway using radiofrequency (RF) energy has been established as the first-line curative therapeutic modality of recurrent symptomatic AV nodal reentrant tachycardia (AVNRT). In contrast to catheter ablation of the AV bypass tract, there was no useful marker to localize succesful site of the pathway. This study was performed to determine predictors of successful catheter ablation of the AV nodal slow pathway in patients with AVNRT. METHODS: Forty patients (18 men, 22 women; 47.9+/-13.3 years) with AVNRT undergoing successful catheter ablation of the AV nodal slow pathway were included in this study, in which 217 attempts were tried to ablate the AV nodal slow pathway. Characteristics of local atrial electrogram, anatomical site at each attempt, junctional rhythm during RF delivery were analyzed (40 successful, 177 failed). Maximum difference and duration of atrial electrograms were measured and local atrial electrograms were classified into 5 types (A1, A2, B1, B2 and C type) according to the type and the degree of fragmentation. Finally, the occurrence of junctional rhythm during RF discharge and its onset time were compared between successful and failed attempts. RESULTS: There was no significant difference in the maximum difference of amplitude and duration of atrial electrograms between successful and failed attempts. The success rate in each type of atrial electrogram was significantly different. And, the success rate in non-C type atrial electrograms (A1, A2, B1, and B2) was significantly higher than that in type C atrial electrograms (25.0% vs 10.3%, p<0.01). No significant difference was noted in success rates according to attempted sites. Junctional rhythms during radiofrequency application occured significantly more frequent in successful attempts than in failed attempts (87.5% vs 47.5%, p<0.001). The time to onset of junctional rhythm was not different between successful and failed attempts (5.2+/-4.9 sec vs 6.1+/-5.5 sec). CONCLUSION: Fragmented local atrial electrogram and junctional rhythm during RF energy delivery may be used to predict successful catheter ablation of AVNRT. It is recommended that RF energy should be applied to the site where fragmented atrial electrogram is recorded and terminated if junctional rhythm does not develop within 15 seconds after starting RF energy delivery.

The Effects of Local Endothelin Receptor Blocker Delivery on Porcine Coronary Stent Restenosis / 대한내과학회지

OBJECTIVES:Coronary stent is one of the most effective currently available devices in the treatment of coronary artery diseases. But, coronary stent restenosis is one of major limitations in clinical stenting. Local drug delivery may be a new strategy for the prevention of stent restenosis. Endothelin receptor blocker is known to have vasodilatory and antiproliferative activities. To investigate the effects of local endothelin receptor blocker delivery on stent restenosis, local delivery was performed in the porcine model of coronary stent restenosis. METHODS: Stent overdilation injury alone was performed in the control porcine coronary arteries (n=4, group A) and local delivery of endothelin receptor blocker prior to stenting was performed in the porcine coronary artery (n=9, group B). Endothelin receptor blocker (TAK-044, Takeda, Japan) was delivered at a rate of 1 ml/min (50 mg/10 ml) using the Dispatch Catheter. Follow-up quantitative coronary angiogram (QCA) and immunohistopathologic assessment were performed 4 weeks after stenting. RESULTS: 1) On QCA, percent diameter stenosis was significantly higher in Group A than in Group B (29.4+/-6.1 % vs. 14.5+/-11.6%, p<0.05). 2) Area stenosis was higher in Group A than in Group B (63.5+/-23.2 % vs. 40.9+/-13.3 %) measured by histopathologic method (p<0.05). 3) Neointimal area was higher in Group A than in Group B (3.53+/-1.9 mm2 vs. 1.75+/-0.8 mm2, p=0.03). 4) By immunocytochemistry, proliferating cell nuclear antigen index was higher in Group A compared with Group B (46.8+/-5.2 % vs. 31.1+/-3.7 %, p<0.05). CONCLUSION: Local delivery of endothelin receptor blocker is effective in the prevention of stent restenosis in a porcine model, which may be related with the partial inhibition of cell proliferation of neointimal cells.

The preventive effects of the heparin-coated coronary stent in a porcine coronary stent restenosis model / 대한내과학회지

BACKGROUND: The coronary stent reduces acute coronary arterial occlusion and late restenosis during and after coronary intervention. However, stent thrombosis and restenosis are still major limitations in widespread use of coronary stent. Local drug delivery with use of heparin-coated stent will be a new approach reducing the incidence of stent thrombosis and restenosis. In order to evaluate the effects of heparin-coated stent on stent restenosis, heparin-coated stents were compared with control stents in a porcine coronary stent restenosis model. METHODS: Stent overdilation injury (stent:artery= 1.3:1.0) was performed with bare Wiktor (Group I, n=10) and heparin-coated Wiktor (Group II, n=20) stents (HEPAMEDTM, Medtronics, U.S.A.) in porcine coronary arteries. Follow-up quantitative coronary angiography (QCA) was performed at 4 weeks after stenting and histopathologic assessments of stented porcine coronary arteries were compared in both groups. RESULTS: 1) On QCA, percent diameter stenosis was significantly higher in Group I than in Group II (16.3+/-6.62% vs. 9.6+/-5.06%, p<0.05). 2) Injury score of stented porcine coronary artery was not different in both groups (1.26+/-0.23 vs. 1.20+/-0.22). 3) Pathologic area stenosis of stented artery was higher in Group I than in Group II (41.6+/-12.5% vs. 27.1+/-9.9%, p<0.005). 4) Neointimal area was higher in Group I than in Group II (4.58+/-1.41 mm2 vs. 2.57+/-1.07 mm2, p<0.05). 5) By immunohistochemistry, proliferating cell nuclear antigen (PCNA) index was higher in Group I compared with in Group II (11.2+/-6.75% vs. 6.3+/-4.14%, p<0.05). CONCLUSIONS: Heparin-coated stent is effective in the prevention of late coronary stent restenosis in a porcine coronary stent restenosis model, which may be related with the inhibition of neointimal cell proliferation.

Effects of Antiplatelet Agents in the Prevention of Ventricular Tachyarrhythmias during Acute Myocardial Ischemia in the Rats

BACKGROUND: Aspirin, one of the antiplatelet agents, improves the survival rate after myocardial infarction. This beneficial effect is known to be obtained in part by the antiarrhythmic action of aspirin. It is not known whether other antiplatelet agents have such effects. This study was performed to compare the effects of aspirin, ticlopidine, and abciximab (platelet glycoprotein IIb/IIIa receptor antagonist) on the ischemia-induced arrhythmias with a rat model of cardiac regional ischemia. METHODS: Experiments were performed in 4 groups of rats. The 4 groups were as follows : control, n=10:aspirin-pretreated, 300 mg/kg po for 1 week:ticlopidine-pretreated, 200 mg/kg po for 1 wk:abciximab-pretreated, 2 mg/kg iv 10-20 minutes before experiment. The electrocardiogram and blood pressure were recorded during 20 minutes. The time to the onset of ST-segment elevation and ventricular tachyarrhythmias, frequency and incidence of ventricular tachyarrhythmias, and death rate were assessed during acute myocardial ischemia induced by ligation of proximal left anterior descending coronary artery in anesthetized rats. RESULTS: Platelet aggregations to ADP were significantly lower in aspirin (42.8%), ticlopidine (43.8%), and abciximab group (34.0%) than in control group (66.4%). The frequencies of sustained ventricular tachycardia (VT) were 6.8+/-3.6 in control, 3.6+/-3.8 aspirin, 4.7+/-3.7 ticlopidine, and 1.4+/-2.5 abciximab group. The frequency of sustained VT in the abciximab group was significantly lower than in control group. The incidences of ventricular arrhythmias for 20 min were 10/10 for VT and 8/10 for ventricular fibrillation (VF) in control group, 7/10 for VT and 3/10 for VF in aspirin group, 10/10 for VT and 3/10 for VF in ticlopidine group, and 5/10 for VT and 4/10 for VF in abciximab group. The incidences of cardiac death during 20 min were 8/10 in control group, 4/10 in aspirin group, 2/10 in ticlopidine group and 5/10 in abciximab group. The incidence of VT in the abciximab group was significantly lower than in control group, incidences of VF in the aspirin and ticlopidine groups were significantly lower than in control group, and death rate in ticlopidine group was significantly lower than in control group. CONCLUSION: The present study suggested that aspirin, ticlopidine, and abciximab could prevent ventricular tachycardia or ventricular fibrillation in a rat model of cardiac regional ischemia and their antiarrhythmic effects improve the survival rate.

Effects of Antiplatelet Agents in the Prevention of Ventricular Tachyarrhythmias during Acute Myocardial Ischemia in the Rats

BACKGROUND: Aspirin, one of the antiplatelet agents, improves the survival rate after myocardial infarction. This beneficial effect is known to be obtained in part by the antiarrhythmic action of aspirin. It is not known whether other antiplatelet agents have such effects. This study was performed to compare the effects of aspirin, ticlopidine, and abciximab (platelet glycoprotein IIb/IIIa receptor antagonist) on the ischemia-induced arrhythmias with a rat model of cardiac regional ischemia. METHODS: Experiments were performed in 4 groups of rats. The 4 groups were as follows : control, n=10:aspirin-pretreated, 300 mg/kg po for 1 week:ticlopidine-pretreated, 200 mg/kg po for 1 wk:abciximab-pretreated, 2 mg/kg iv 10-20 minutes before experiment. The electrocardiogram and blood pressure were recorded during 20 minutes. The time to the onset of ST-segment elevation and ventricular tachyarrhythmias, frequency and incidence of ventricular tachyarrhythmias, and death rate were assessed during acute myocardial ischemia induced by ligation of proximal left anterior descending coronary artery in anesthetized rats. RESULTS: Platelet aggregations to ADP were significantly lower in aspirin (42.8%), ticlopidine (43.8%), and abciximab group (34.0%) than in control group (66.4%). The frequencies of sustained ventricular tachycardia (VT) were 6.8+/-3.6 in control, 3.6+/-3.8 aspirin, 4.7+/-3.7 ticlopidine, and 1.4+/-2.5 abciximab group. The frequency of sustained VT in the abciximab group was significantly lower than in control group. The incidences of ventricular arrhythmias for 20 min were 10/10 for VT and 8/10 for ventricular fibrillation (VF) in control group, 7/10 for VT and 3/10 for VF in aspirin group, 10/10 for VT and 3/10 for VF in ticlopidine group, and 5/10 for VT and 4/10 for VF in abciximab group. The incidences of cardiac death during 20 min were 8/10 in control group, 4/10 in aspirin group, 2/10 in ticlopidine group and 5/10 in abciximab group. The incidence of VT in the abciximab group was significantly lower than in control group, incidences of VF in the aspirin and ticlopidine groups were significantly lower than in control group, and death rate in ticlopidine group was significantly lower than in control group. CONCLUSION: The present study suggested that aspirin, ticlopidine, and abciximab could prevent ventricular tachycardia or ventricular fibrillation in a rat model of cardiac regional ischemia and their antiarrhythmic effects improve the survival rate.

Predictors for In-stent Restenosis after Coronary Microstent II Implantation

BACKGROUND: Coronary stent is known as an effective treatment in the intimal dissection after angioplasty and the prevention of restenosis. However, in-stent restenosis still remains a major concern in clinical stenting. METHOD: The Microstents were placed in 151 patients from May '96 to Aug '97 and performed follow-up coronary angiograms in 49 (32.5%) patients. To identify the clinical, angiographic and procedure-related variables that predict late restenosis within the stented artery, 49 patients (58+/-8 year:38 M, 11 F) were studied. Indications for stenting were 25 de novo (52.8%), 9 restenotic (18.7%), 8 suboptimal PTCA (16.7%) and 6 bail-out lesions (12.6%). All patients were treated with aspirin and ticlopidine for one month after stenting. The follow-up angiograms were obtained at 5+/-3 months and variables of 13 patients with restenosis were compared with those of 36 patients without restenosis. RESULTS: The in-stent restenosis rate was 26.5%. Univariate logistic regression analysis was used to determine how in-stent restenosis was influenced. Clinical diagnosis, presence of risk factors, lipid profiles, numbers of involved vessels, target arteries, lesion length, lesion types, stent length, maximal inflation pressure, predilation balloon size, reference vascular diameter, minimal luminal diameter, and stent to artery diameter ratio were analyzed. Among these variables, only lesion length before stent implantation was a predictor for in-stent restenosis (19.9+/-11.1 mm vs. 10.9+/-7.3 mm, p=.017). CONCLUSION: Lesion length before Microstent II implantation is the single predictor of late in-stent restenosis.

Two Cases of Sliding Hiatal and Morgagni Hernia Mimicking Pericardial Lipomas

The differential diagnosis between pericardial and non-cardiac masses may be sometimes difficult in the evaluation of chest mass adjacent to the heart. One misdiagnosed case of non-cardiac mass as a pericardial mass turned out to be a hernia. When the contents of hernia originate from the gastrointestinal tract, the diagnosis is made easily by air-fluid shadow on plain chest roentgenogram. Morgagni hernia is usually detected on plain chest roentgenograms as a smooth, supradiaphragmatic shadow at the right pericardiophrenic angle. In the case of Morgagni hernia, in which the contents are only the omentum, it is necessary to differentiate the hernia from mediastinal fatty tumors. We report two cases of hiatal and Morgagni hernia containing omentum which were misdiagnosed as pericardial masses.

Alterations in Myocardial Perfusion and Regional Wall Motion in Patients with Permanent Pacemaker

BACKGROUND: The effect of right ventricular pacing on myocardial perfusion and regional wall motion is not well known, although some studies have suggested that it may be adverse. We investigated the effects of right ventricular pacing on myocardial perfusion and regional wall motion in patients with permanent pacemakers. METHOD: Thirty patients receiving permanent pacemakers for complete heart block or sick sinus syndrome were included in this study. All the patients showed normal coronary angiograms. Myocardial scintigraphy and two-dimensional echocardiography were performed to assess myocardial perfusion and to evaluate regional wall motion and global function of the left ventricle (LV). RESULTS: 1) Mean age was 66.2+/-8.2 (41-84) years, and the male-to-female ratio was 1 : 1.7 (11 male, 19 female). Indications for permanent pacemaker implantation were complete atrioventricular (AV) block in 21 patients and sick sinus syndrome in 9. The selected pacing modes were VVI in 14 patients, DDD in 8, VDD in 6, and AAI in 2. LV ejection fraction estimated by 2-dimensional echocardiography was 62.7+/-5.8 (53-86)%. 2) Perfusion defects were noted in 26 (87%) patients including 25 (89%) out of 28 patients with ventricular pacing modes such as VVI, DDD, and VDD, and 1 (50%) out of 2 patients with AAI mode. Locations of perfusion defects were septal in 19 (63%) patients, inferior in 17 (57%), apical in 16 (53%), lateral in 3 (10%), and anterior in 2 (7%). Extent of maximal perfusion defects was 17.0+/-9.5 (0-44)%. 3) Regional wall motion abnormalities were noted mainly over the apical region of the LV in 26 (93%) of 28 patients with ventricular pacing. However, LV ejection fraction did not differ significantly before and early after implantation of the pacemaker (62.7+/-5.8% vs. 61.0+/-5.8%, p-0.313). CONCLUSIONS: Right ventricular apical pacing frequently caused myocardial perfusion defects and regional wall motion abnormalities. These might be due to abnormal ventricular activation and abnormal interventricular septal motion. The long-term effects of these abnormalities remain to be determined, and the pacing technique to minimize these adverse effects should be developed.

Comparison of Porcine Corinary Stent Restenosis between MAC (Maximum Arterial Re-Creation)and Palmaz-Schatz Stent

BACKGROUND: Coronary stents are effective in the treatment of acute complications after angioplasty and the prevention of restenosis. However, complications may arise posttreatment, the major cinical problems are stent thrombosis and restenosis. All coronary stents are imported from western countries and are not covered by medical insurance in Korea. Korean stents should be developed to reduce patient's economic burden. METHODS: We placed five Maximum Arterial Re-Creation (MAC) and five Palmaz-Schatz (PS) stents in ten porcine coronary arteries. Stent and artery diameter ratio was 1.3 : 1.0. Follow-up coronary angiogram and histopathologic examinations were performed four weeks after stent overdilation injury. RESULTS: All of the stented arteries were patent on follow-up coronary angiograms. Angiographic diameter stenosis was 23.1+/-9.2% in MAC stents and 18.5+/-12.3% in PS stents and pathologic area stenosis was 35.6+/-11.4% in MAC stent and 39.8+/-9.9% in PS stent at 4 weeks after stenting, which were not different between two stents. Maximal intimal thickness (0.28+/-0.12 vs. 0.36+/-0.17mm) and neointimal area (1.83+/-1.01mm2 vs. 1.50+/-0.65mm2) were not different between MAC and PS stent. CONCLUSIONS: MAC stents are as effective as PS stents in the prevention of stent restenosis in a porcine stent restenosis model.

Clinical Characteristics of Korea Women with Ischemic Heart Disease

BACKGROUND: The prevalence of ischemic heart diseases (IHD) has increased remarkably during the past 10 years in Korea. Because only few reports on risk factors of IHD in Korean women exist, the aim of this study was to determine the clinical characteristics (including risk factors) of IHD in Korean women. METHODS: Fifty-six female patients and 122 (out of 655) of male patients with significant coronary artery stenosis were included in this study. There were 12 cases of angina pectoris and 35 cases of myocardial infarction in the 56 female patients. There were 54 cases of angina pectoris and 68 cases of myocardial infarction in the 122 male patients. Age and sexdistributions, risk factors of atherosclerosis, and coronary angiographic findings were compared between the female and male patients. RESULTS: The female patients were older than the male patients (63+/-8 years vs. 58+/-4 years, p or = 2) was greater in men than in women (43% vs. 25%, p<0.05). Hypertension was more prevalent (66% vs. 11%, p<0.001) and smoking was less (65% vs. 11%, p<0.001) in women than men. After age adjustment, hypertension was more frequent in women, and smoking was more in men (p=0.001). On coronary angiograms there were no difference in the morphology of coronary artery stenosis, the distribution of culprit vessels, and the number of vessels involved between women and men, In terms of therapeutic modalities, there were no differences between women and men in our study. CONCLUSIONS: In Koean women with IHD, hypertension is more common and smoking is less common. However, coronary artery lesion morphology and distribution are comparable between women and men.

The Effects of Oral Nitric Oxide Donor (Molsidomine) in Patients with Variant Angina Unresponsive to Conventional Anti-Anginal Drugs

BACKGROUND: We observed the changes of clinical characteristics after oral Molsidomine, a nitric oxide donor, in patients who have documented coronary artery spasm by ergonovine coronary angiogram and refractory to conventional anti-anginal therapy. METHOD: Molsidomine, oral nitric oxide donor, was administrated over 12 weeks in 20 patients (6 male, 14 female, 54+/-11.5 years) in order to observe the clinical effects in patients with coronary artery spasm unresponsive to nitrate and calcium channel blockers. Changes in the frequency of pain and sublingual nitroglycerin use, blood pressure, heart rate, side effects, electrocardiogram, and laboratory findings were evaluated before and after Molsidomine therapy. RESULTS: The frequencies of pain and sublingual nitroglycerin use were 3.9+/-0.9/week before treatment and decreased to 2.9+/-0.9/week at 4th week after the additional Molsidomine treatment (pre-treatment vs. 4th week; p<0.001), to 1.0+/-0.8/week at 8th week (4th week vs. 8th week; p<0.001), and to 0.7+/-0.8/week at 12th week. Systolic blood pressure decreased after treatment, but there were no significant changes in diastolic blood pressure, heart rate, resting electrocardiogram and laboratory findings. Molsidomine was discontinued in one patient because of headache. CONCLUSIONS: Molsidomine is an effective and well tolerated anti-ischemic agent in patients with variant angina refractory to conventional anti-anginal therapy.

The Effects of Therapeutic Duration of Combined Antiplatelets, Aspirin and Ticlopidine, on Coronary Stent Restenosis

BACKGROUND: One of most important mechanisms of coronary stent restenosis is neointimal hyperplasia. Although the process of neointima formation is not fully understood, a special role has been advocated for adherent platelets. Previous studies have shown a clear benefit with combined antiplatelet therapy such as aspirin plus ticlopidine in reducing the rate of thrombotic occlusions of stented vessels. The purpose of this study was to evaluate the effects of duration of antiplatelet regimens on coronary stent restenosis. METHODS: After successful placement of coronary artery stents in 222 patients, we performed follow-up coronary angiograms in 99 patients (42.3%). Forty-six patients were randomly assi-gned to receive aspirin and ticlopidine for four weeks (Group I: 54+/-9 years: M 38, F 8) and 48 patients for 6 months (Group II: 58+/-8 years: M 38, F 10). RESULTS: There were no significant differences in clinical and procedural variables or coronary lesion characteristics before and after stenting. At 6 months after stenting, minimal luminal diameter was 2.16+/-0.93mm in Group I and 2.04+/-1.07mm in Group II (p-0.57). Late lumen loss was 0.80+/-1.07mm in Group I and 0.92+/-1.11mm (p-0.58) in Group II. The stent restenosis rate of Group I at 28.3% and that of Group II at 29.2% were not statistically significant between the two groups (p-0.92). CONCLUSIONS: The therapeutic duration of combined antiplatelet regimen with aspirin and ticlopidine after coronary stent does not affect stent restenosis rate.

Clinical Characteristics of Coronary Interventions in Old Aged Patients

BACKGROUND: Coronary intervention is one of well established therapeutic modalities for patients with ischemic heart diseases. With the prolonged life expectancy and changes in dietary habits in Korea, the number and percentage of elderly patients with ischemic heart disease have increased in interventional coronary therapies. METHOD: There were 1762 patients (age> or = 70 years : 253, age<70 years: 1509) who underwent diagnostic coronary angiogram at Chonnam University Hospital between Jan '96 and Jun '97. We compared clinical characteristics, coronary lesion morphology, success rates and complications of coronary interventions in control and aged groups. RESULTS: 1) Female patients were more prevalent in aged group (43 %; 145 male, 108 female) than in the control group (35%; 982 male, 527 female, p<0.05). 2) The diagnostic sensitivity of coronary angiogram was higher in the aged (169/253, 67 %) than in control group (738/1509, 49 %, p<0.05). Multivessel diseases were more prevalent in the aged (65 %) than in the control groups (49%). 3) Coronary interventions were performed less frequently in the aged group (119/169, 70 %) than in the control group (605/738, 82%, p<0.05). The success rates of PTCA were not different between in the aged (89%) and control (93%) groups, and the success rates in stenting was also not different between the aged (98%) and control (99%) groups. 4) Procedure-related complications (4.6 vs. 7.6 %) and mortalities (0.5 vs 0.8 %) during and after coronary interventions were not different in control and elderly groups. CONCLUSION: Coronary interventions in patients older than 70 years can be performed with high success and low complication rates ; the results do not differ from those of younger patients.

The Early Results of Clinical and Angiographic Follow-up after Coronary Interventions for Restenotic Lesions

BACKGROUND: Coronary intervention is a well established treatment of ischemic heart diseases. However, acute arterial occlusion and restenosis have remained as the principal limitations of coronary intervention. This study was aimed to analyze the acute and long-term, and the clinical angiographic results of the coronary intervention for restenotic lesions. METHOD: Between March 1996 and July 1997 at Chonnam University Hospital, second interventions were performed in one hundred restenotic coronary lesions of ninety patients (age 58.5+/-9.0 year, M:F = 5:1), i.e. percutaneous transluminal coronary angioplasty (PTCA) or stent implantation for the treatment of restenosis. RESULTS: 1) Initial interventions were PTCA in 75 lesions (Group I) and stent in 25 lesions (Group II). There were no differences in clinical manifestations, angiographic findings and follow-up period between the two groups. 2) The method of the second intervention for the restenotic lesions after PTCA were either PTCA or stent implantation ; in Group I PTCA was performed in 27 (37%) lesions and stent in 46 (63%), In Group II, PTCA was performed in 20 (91%) lesions and stent in 2 (9%) lesions. The overall success rate of the second intervention for the restenotic lesion was 96%. 3) Follow-up angiogram at 5.5+/-2.9 months after the second intervention revealed the second restenosis rates of 44% (8/18) after stent and 50% (7/14) after PTCA. CONCLUSION: Second intervention for restenotic lesion can be performed with high success rate. Second restenosis rate are not different between the PTCA and stent groups.