The Response of Coronary Artery Diameter to Acetylcholine in Patients with or Without Minimally Diseased Coronary Artery*

BACKGROUND: Coronary artery spasm plays an important role in the pathogenesis of not only variant angina but also other forms of angina,acute myocardial infarction, and sudden death. However precise mechanisms by which coronary spasms occur remains unknown. The role of increased coronary artery tone as a part of pathogenesis of conary spasm and relation to the severity of coronary artery disease are still controversial. Thus we underwent this study to investigate the role of increased coronary artery tone as a part of pathogenesis of conary spasm and realtion to the severity of coronary artery disease. METHODS: Intracoronary acetylcholine and isosorbide dintrate were used as a spasm-provocative agent and vasodilator respectively. We analyzed 176 vessels(69 right coronary artery, 58 left anterior descending coronary artery, 49 left circumflex coronary artery) of 75 patients admitted for evaluation of chest pain syndrome. Among the 176 vessels, spasm occurred in 39 vessels of 25 patients. RESULTS: 1)Coronary artery spasm occured in 30.4%(21/69), 17.2%(10/58), 16.3%(8/49) of right coronary artery, left anterior descending coronary artery, left circumflex coronary artery respectively. 2) There is no relationship between angiographically visible minimal coronary artery disease and occurrence of spasm provoked by acetylcholine. 3) There was no significant difference of coronary risk factor predicting coronary spasm between two groups. 4) There is more significant % vasodilation by isosorbide dintrate(ISDDN) occurred din both the spastic and nonspastic arterial segment of vasospastic angina group than no spasm group(30.2%, 28.4% vs 14.2%, p<0.05). 5) Degree of % vasodilation by ISDN was more significantly larger in vasospastic angina group than no spasm group despite the presence of same amount of angiographically visible minimal coronary artery disease(38.3% vs 12.5%, p<0.05). CONCLUSION: These findings suggests that the occurrence of conronary artery spasm is not related to minimal coronary artery disease. Increased coronary artery tone observed only in vasospastic angina group may be part of pathogenesis of coronary spasm.

Influence of Balloon Size and Morphology of Coronary Stenosis on Elastic Recoil after Percutaneous Transluminal Coronary Angioplasty

BACKGROUND: The immediate result of coronary balloon angioplasty was influenced by plastic and elastic changes of the vessel wall. After successful coronary angioplasty, the minimal luminal diameter of the dilated coronary artery segment was generally smaller than the diameter of the largest balloon catheter at the maximal inflation pressure. Several mechanisms could explain this phenomenon, including vasoconstriction, subintimal or intraplaque bleeding or edema and platelet or thrombus deposition. In addition, whenever balloon inflation results in overdistension of elastic components of the arterial wall, some degree of elastic recoil may occur. METHODS: To evaluate magnitude of elastic recoil after percutaneous transluminal coronary angioplasty in relation to lesion morphology and other procedure-related variables, 141 coronary lesions were selected from patients with acute myocardial infarction, stable angina, unstable angina and post myocardial infarction angina undergoing successful coronary angioplasty. Coronary angiograms were recorded before and after angioplasty, and during dilatation of balloon. The computer measuring program was used for the assessment of balloon diameters and coronary luminal diameters. RESULTS: 1) Of all 141 coronary lesions, percent diameter stenosis before angioplasty averaged 74.2% and after angioplasty averaged 22.5%. 2) Residual diameter stenosis was directly related to the degree of elastic recoil, the greater the elastic recoil the more severe the residual lesion immediately after angioplasty. The increase in elastic recoil corresponded to a increase in the balloon/artery ratio(p<0.05). 3) The residual diameter stenosis tended to decrease in segments dilated with an oversized balloon than with an undersized balloon(p<0.05). 4) The elastic recoil increased significantly in the subgroups of coronary segments dilated with an oversized balloon, of eccentric lesion, and type C lesion(p<0.05). 5) Percent residual stenosis was more sever in eccentric stenosis dilated with undersized balloon than in concentric stenosis. 6) Elastic recoil was greater in type C coronary segment dilated with an oversized balloon than with an undersized balloon(<0.05). 7) The lesion dilated with oversize non-compliant balloon showed more elastic recoil than with oversize compliant balloon(p<0.05). CONCLUSION: Factors such as oversized balloon, eccentric lesion, type C lesion, and non-compliant balloon significantly affected increase of the elastic recoil.

Determinants of Successful Percutaneous Transluminal Coronary Angioplasty / 영남의대학술지

In Order to evaluate determinants of successful percutaneous transluminal coronary angioplasty (PTCA), PTCA was performed for 172 coronary arterial lesions in 120 patients(89 male, 31 female) at Yeungnam university hospital from Sep. 1992 to Aug 1993. The corinary artery luminal diameter at the site of the original stenosis was eveluated from end-diastolic frames of identical projections of the preangioplasty and immediate post angioplasty. The coronary luminal and balloon diameters were measured with using of computer measuring system. Overall success rate of 172 attempted lesions was 87.2%. Success rate of female patients was 93.5% and higher than those of male patients. According to the clinical diagnosis, success rate in stable angina was 93.7% and higher than those of post myocardial infarction angina, unstable angina and acute myocardial infarcrion. Success rate of American Heart Association type C lesion was 65.5% and lower those of type A(95.7%), type B (89.%). There was significantly difference in preangioplasty luminal stenosis, elastic recoil and length of lesion between successful PTCA group and failed PTCA group. Success rate of lesion location at a bed >45° and presence of intracoronary thrombus were lower than than those of other angiographic findings. In coclusion, primary angioplasty success was affected by specific angiographic factors, Stenosis severity, thrombus, lesion location at a bend >45°, elastic recoil, and length of lesion were the principle of determinants of coronary angioplasty success rate.

Prevalene of Secondary Hypertension in Yeungnam University Hospital / 영남의대학술지

We studied the incidence and results of treatment of secondary hypertension in Yeungnam University Hospital. Nineteen hundred fifty patients with hypertension were included from march 1990 to march 1994. We analysed the prevalence of secondary hypertension and results of treatment. The incidence of secondary hypertension in Yeungnam University Hospital was six percent. The most common underlying causes of secondary hypertension was renal parenchymal disease. Patients with three forms of potentially reversible secondary hypertension, namely, renovascular hypertension, endocrine disease, exogenous hormone, were assed to determine whether surgery or withdrawal of the exogenous hormane had led to an improvement in blood pressure control. The incidence of secondary hypertension in Yeungnam University Hospital was low(6%), but some of these are curable. Thus it is very inportant that evaluate the secondary hypertension.

A Case of Disappearing Symptoms Developed Repetitively in a Complete Atrioventricular Block Patient Implanted Bipolar Permanent Pacemaker After Converting It into Unipolar System / 영남의대학술지

Pacemaker malfunctions are secondary to alterations of the preset pacing rate, irregular pacing failure of sensing, failure of cardiac capture or depolarization, and various combinations of these events. A 76 years old male patients was admitted due to pacemaker malfunction. 2 years ago, he was diagnosed as complete atrioventricular block. And then bipolar permanent pacemaker was implanted. Since then syncopal attack developed repetitivly. 12 lead ECG and 24 hour holter moniter monitoring, revealed pacing and sensing failure, thus we converted bipolar system into unipolar system. since then syncopal attack did not developed again.