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The ST segment corresponds to the plateau phase of ventricular repolarization, i.e., phase 2 of the action potential. Heightened awareness of the characteristic patterns of ST segment changes is vital to quickly identifying life-threatening disorders. The differential diagnosis of ST segment elevation includes four major processes: ST segment elevation myocardial infarction (STEMI); early repolarization; pericarditis; and ST elevation secondary to an abnormality of the QRS complex (left bundle branch block, left ventricular hypertrophy, or preexcitation). Other processes that may be associated with ST elevation include hyperkalemia, pulmonary embolism, and Brugada syndrome. Two particular patterns of ST segment depression reflect STEMI rather than non-ST-segment elevation acute coronary syndrome: ST segment depression that is reciprocal to a subtle and sometimes overlooked ST-segment elevation, and ST segment depression that is maximal in leads V₁-V₃, suggesting true posterior infarction. The clinical setting and specific electrocardiographic criteria often allow identification of the cause.
Subject(s)
Action Potentials , Acute Coronary Syndrome , Brugada Syndrome , Bundle-Branch Block , Depression , Diagnosis, Differential , Electrocardiography , Hyperkalemia , Hypertrophy, Left Ventricular , Infarction , Myocardial Infarction , Pericarditis , Pulmonary EmbolismABSTRACT
Background: ST-segment depression in ECG is a common finding during paroxysmal supraventricular tachycardia. The exact mechanism and etiology of this ST-segment depression is not always evident. In this study we have tried to evaluate the significance of ST-segment depression during supraventricular tachycardia. Methods: Hospitalized patients for elective electrophysiological study with previous (EPS) history of supraventricular tachycardia with or without ST-segment depression were evaluated clinically, by coronary angiogram and EPS. Data were analyzed by appropriate statistical methods and comparison made between groups with ST-segment depression (Group A) and without ST-segment depression (Group B). Results: Total number of patients was 66. Equal number of patients (33) was in each group. The mean age of patients was 43.8 years. There was female predominance (M:F ratio 2:3). The mean heart rate during supraventricular tachycardia was 161 beats/min. Age, sex, coronary artery disease risk factors and heart rate during an episode of supraventricular tachycardia did not have any significant influence on ST-segment depression. Significant coronary artery disease was found in two patients in Group A and one patient in Group B. Electrophysiological study revealed that Atrio ventricular reentry tachycardia (AVRT) and AV nodal reentry tachycardia (AVNRT) were present in 28 (42.4%) and 38 (57.6%) cases respectively. Patients of group A exhibit AVRT significantly more than patients of group B.The sensitivity of ST-segment depression in correctly diagnosing coronary artery disease (CAD) was 66.7% while the specificity was 50.8%. The sensitivity of ST-segment depression in correctly differentiating AVRT was 83.3% while the specificity was 66.7%. The positive predictive value (PPV) and Negative predictive value (NPV) of the test were 75% and 76.9% respectively. Conclusion: ST-segment depression during episode of supraventricular tachycardia is a poor indicator of coronary artery disease. Presence of ST-segment depression can differentiate AVRT from AVNRT. However, >2 mm ST-segment depression was proved to be an excellent predictor of AVRT.
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Introducción: La utilidad clínica de la capacidad de la ergometría para indicar la presencia y gravedad funcional de las obstrucciones coronarias se ve limitada por las relativamente bajas sensibilidad y especificidad del infradesnivel del segmento ST (infra-ST), lo cual hace necesaria la investigación de las modificaciones de otras variables electrocardiográficas durante el esfuerzo que puedan aportar información adicional y complementaria a la del infra-ST. Se ha demostrado que el evento más temprano en la primera fase de la lesión transmural es la prolongación del intervalo QT corregido (QTc). Objetivos: Investigar si las modificaciones del intervalo QTc inducidas por el esfuerzo máximo (QTc máx) sumadas al infra-ST ≥ 1 mm permiten incrementar la capacidad de la ergometría para diagnosticar la presencia de enfermedad arterial coronaria significativa y si otros signos pueden aportar también información útil para identificar a estos pacientes. Material y métodos: Ciento sesenta y seis pacientes con infra-ST ≥ 1 mm durante la fase de ejercicio y/o recuperación de una ergometría a los que posteriormente se les realizó una coronariografía se distribuyeron en dos grupos: Grupo I (GI): 118 pacientes que mostraron prolongación del intervalo QTc máx y Grupo II (GII): 48 pacientes que acortaron normalmente el QTc máx. Se analizaron parámetros clínicos, ergométricos y electrocardiográficos y la angiografía coronaria para comprobar la presencia de enfermedad arterial coronaria significativa. Resultados: En 102 de los 166 pacientes incluidos (61,4%) se diagnosticó enfermedad arterial coronaria significativa, todos ellos pertenecientes al GI. El GI mostró alta prevalencia de pacientes con enfermedad arterial coronaria significativa (86,4% vs. 0%; p < 0,001), bajo umbral isquémico, recuperación tardía del infra-ST, mayor ensanchamiento del complejo QRSmáx, incompetencia cronotrópica y baja tolerancia al ejercicio. Durante la prueba ergométrica graduada los pacientes del GII presentaron mayor prevalencia de hipertensión arterial grave y el infra-ST < 1 mm en el segundo minuto del posesfuerzo. El incremento del intervalo QTc máx resultó un predictor independiente de enfermedad coronaria (p < 0,001). Conclusiones: La prolongación del intervalo QTc máx sumado al infra-ST ≥ 1 mm incrementó notoriamente la capacidad de la prueba ergométrica graduada para diagnosticar la presencia de enfermedad arterial coronaria significativa, patología que estuvo ausente en todos los pacientes con infra-ST que acortaron normalmente el QTc máx.
Background: The clinical usefulness of exercise stress testing to indicate the presence and functional severity of coronary artery stenoses is limited by the relatively low sensitivity and specificity of ST-segment depression. Therefore, the modifications of other electrocardiographic variables during exercise, which may provide additional and complementary information to ST-segment depression, should be investigated. It has been demonstrated that the corrected QT interval (QTc) prolongation is the earliest event during the first stage of transmural ischemia. Objectives: The aim of this study was to investigate whether modifications of the QTc interval induced by maximal exercise (QTcmax) together with ST-segment depression ≥ 1 mm can increase the capability of the stress test to detect significant coronary artery disease and if other signs may also provide useful information to identify these patients. Methods: One hundred and sixty six patients with ST-segment depression ≥ 1 mm during exercise or during the recovery stage of a stress test underwent coronary angiography. They were divided into two groups: Goup I (GI): 118 patients with QTcmax interval prolongation and Group II (GII): 48 patients with normal QTcmax shortening. Clinical, stress test-related and electrocardiographic parameters and coronary angiography were analyzed to identify the presence of significant coronary artery disease. Results: Significant coronary artery disease was detected in 102 of the 166 patients included in the study (61.4%), all from GI. Group I showed high prevalence of patients with significant coronary artery disease (86.4% vs. 0%; p < 0.001), low ischemic threshold, late recovery of ST-segment depression, wider QRSmax complex, chronotropic incompetence and low exercise capacity. During graded exercise stress testing, GII patients presented greater prevalence of severe hypertension and ST-segment depression < 1 mm two minutes after exercise. Increased QTcmax interval resulted as an independent predictor of coronary artery disease (p < 0.001). Conclusions: QTcmax interval prolongation plus ST-segment depression ≥ 1 mm produced a considerable increase in the capability of exercise stress testing to detect significant coronary artery disease, which was absent in all the patients with ST-segment depression and normal QTcmax shortening.
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Objective To observe the incidence of fragmented QRS complex (fQRS)and ST Segment depression fQRS (STD fQRS)during the first 48 hours after non-ST elevation myocardial infarction(NSTE MI)and discuss the value of predicting mortality in patients with NSTE MI .Methods Based on the ECGs ,the patients with NSTE MI were divided into two groups :fQRS and non fQRS group .And then fQRS group was divided into two sub-groups :STD fQRS and non-STD fQRS group .Their mortality was studied during long-term follow-up .Results (1)731 patients with NSTE ACS [the NSTE MI group(n=609) and the UA group(n=122)] were studied .The incidence of fQRS in the NSTE MI group was higher than that of the UA group .(2)All cause mortality in the fQRS group were higher than that in the non-fQRS group ,and all-cause mortality in the STD fQRS group were higher than that in the non-STD fQRS group ,all the above results were not only in the early stages of NSTE MI ,but also in the long term fol-low-up .(3) Multivariate Cox regression analysis revealed that STD fQRS was an independent significant predictor for all cause mortality ,but not of the fQRS .Conclusion The STD fQRS may be an independent predictor of mortality in patients with NSTE MI .
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Objective To determine whether sleep-disordered breathing (SDB) may lead to nocturnal myocardial ischemia and whether the severity of this ischemia may be relieved by nasal continuous positive airway pressure (CPAP). Methods Overnight polysomnogram examination and simultaneous 3-channel Holter monitoring were performed on 76 patients with moderate to severe SDB and no history of coronary heart disease. All the cases were treated with CPAP for one night. ST depression was defined as a ST segment decrease of more than 1 mm from baseline and lasting 1 min or more. The total duration (minutes) of ST depression was indexed to the total sleep time (minutes per hour of sleep). Results Twenty-eight patients (37%) showed ST segment depression during their sleep. Before CPAP treatment, the respiratory disturbance index (RDI) and arousal index were significantly higher during periods of ST depression than when ST segments were isoelectric, whereas no significant difference was found in blood oxygen saturation (SaO2). After the CPAP treatment of patients with ST depression, the duration of ST depression was significantly reduced from 36.8±18.9 to 11.4±13.2 min/h (P＜0.05). ST depression-related indexes, including RDI, arousal index and the percentage of sleep time spent at SaO2 below 90% (TS90/ TST), were all significantly decreased, with RDI from 63.4±23.8 to 8.1±6.6 /h, arousal index from 51.2±18.9 to 9.6±5.4 /h, and TS90/ TST from 50.6±21.4 to 12.9±14.7% (P＜0.05). Conclusion ST-segment depression is rather common in patients with moderate to severe SDB, and CPAP treatment can significantly reduce the duration of ST depression. ST depression in these patients may reflect the myocardial ischemia that really exists and the non-ischemic changes associated with recurrent SDB.
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Objective: To investigate selected cardiovascular responses of post myocardial infarction patients(PMIP)during exercise within the context of different levels of ST segment depression. Method: Forty-six male recent PMIP performed a graded exercise test on a motorized treadmill during which time blood pressure and heart rate were measured and a 12 lead electrocardiogram (ECG) was monitored continuously. They were then subdivided into those ST segment depression ＜1.0 mm at exercise stage Ⅱ (group 1) and those who had ST segment depression ＞1.0 mm at this stage (group 2). Result: The results showed that the patients with a larger degree of ST segment depression at the given work load exhibited higher a value of rate-pressure product (RPP).Conclusion: RPP may be of particular value in estimating the clinical response to exercise when ECG monitoring is not available.
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Double product (DP, heart rate × systolic blood pressure) during an incremental exercise test has been known to start to increase steeply at a workload, i. e. double product break point (DPBP), which corresponds to the blood lactate threshold. The study was to investigate the relationship between DP transition and ST segment depression in electrocardiogram during exercise. Thirty-one patients of angina pectoris of effort and 140 elderly persons performed a continuous incremental exercise test using a stationary bicycle ergometer. During the entire test, HR and blood pressure were measured every 15 seconds and an electrocardiogram was recorded continuously. DPBP was then calculated. In ten of the 31 patients, ST level depression above -0.1 mV with a typical ischemic form in lead V 5 was observed during the test. However, workload at the DPBP was significantly lower than that of the ischemic threshold on the electrocardiogram (i. e. -0.1mV of ST depression) in relation to work load (46+/-16 vs. 78+/-20 watts), HR (96+/-13 vs. 117+/-13 bpm), SBP (160+ /-20 vs. 199+/-31 mmHg) and DP (15400+/-3400 vs. 23400+/-4900 bpm × mmHg) . In elderly persons, DPBP could be determined without the ischemic ST depression in 96% of 327 tests. This study indicated that the DPBP would be an objective index of exercise intensity with lower risk for exercise prescription in cardiac patients and elderly persons.
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BACKGROUND: Exercise electrocardiogram is the most widely used non-invasive test in those patients suspected of having coronary artery disease. However, sensitivity and specificity of this test are not satisfactory, especially when the exercise induced ST-segment depression is used as a single criterion of myocardial ischemia. Although many investigators have tried to improve diagnostic accuracy with R-wave amplitude change in addition to ST-segment depression, controversy exists whether this new criteria improve the test accuracy for coronary artery disease or not. The purpose of this study is to determine the test accuracy of R-wave amplitude change induced by exercise combined with the conventional ST-segment criterion for myocardial ischemia. METHODS: We reviewed our records of patients who visited to Korea University Anam Hospital with chest pain from January, 1998 to July, 1999. We included 130 patients with chest pain who had a tredmill test followed by a coronary angiography within 2 months. Patients with change in ST-segment depression (delta STD)> or = 1.00 mm and delta STD> or = 1.00 mm with R wave amplitude decrease (-delta R)> or = 1.00 mm in the same lead in any of 12 leads and delta STD> or = 1.00 mm with R wave amplitude increase (+delta R)> or = 1.00 mm in the same lead in any of 12 leads were compared. According to the findings of coronary angiograms, patients were divided into 4 groups ; normal coronary artery group, mild coronary artery stenosis group (> or = 30% to or = 50% to or = 70%). RESULTS: Fifty three patients (40.7%) had normal coronary angiograms and 77 patients (59.3%) had coronary artery stenosis. There was no significant difference in gender and age. But, patients with coronary artery stenosis had more diabetes mellitus, hyperlipidemia, smoking, previous myocardial infarction history and angina during exercise testing than those without coronary artery stenosis. The sensitivity of exercise EKG is significantly decreased when combined with delta R (delta STD, 74.0%, delta STD with -delta R, 45.5%, delta STD with +delta R, 30.0%, p<0.01), but the The test accuracy is delta STD; 73.7%, delta STD with -delta R; 61.5%, delta STD with +delta R; 57.7%. CONCLUSION: When ST-segment depression is combined with R-wave amplitude change as a marker for myocardial ischemia, the specificity is increased, but the test accuracy of exercise EKG is not improved.
Subject(s)
Humans , Chest Pain , Coronary Angiography , Coronary Artery Disease , Coronary Stenosis , Coronary Vessels , Depression , Diabetes Mellitus , Electrocardiography , Exercise Test , Hyperlipidemias , Korea , Myocardial Infarction , Myocardial Ischemia , Research Personnel , Sensitivity and Specificity , Smoke , SmokingABSTRACT
Objective To explore the significance of ischemic ST-segment depression during supraventricular tachycardia in the diagnosis of coronary heart disease(CAD).Methods From 1992 to 2008,65 patients with supraventricular tachycardia without clinical evidence of CAD in were divided into 2 groups:Group A included 48 cases with ischemic ST-segment depression during supraventricular tachycardia.Group B consisted of 17 cases with non-ischemic ST-segment depression.Group A was divide into 5 groups according to the age.They all underwent coronary angiography.Results 23(47.92%) of 48 cases in Group A had CAD,while none in Group B(P
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BACKGROUNG AND OBJECTIVES: To evaluate the clinical and prognostic significance of precordial ST segment depression in precordial leads on admission electrocardiogram (ECG) in acute inferior myocardial infarction treated with intravenous thrombolytic therapy. We analysed about clinical and angiographic characters. MATERIALS AND METHOD: ECG findings in 50 patients with acute inferior myocardial infarction were retrospectively studied with results of coronary angiography and clinical informations. We classified all patients in two group according to the admissional ECG. Twenty nine patients (Group A) had no or or =1.0 mm ST depression in two or more precordial (V1-V6) leads were included in this group. RESULTS: In precordial ST segment depression in acute inferior myocardial infarction patients had higher plasma peak mean CK levels (1945+/-1419 vs 3547+/-2728 IU/L, p=0.027) and lower LV ejection fraction (62+/-10% vs 53+/-11%, p=0.008) and lower left ventricle global chordal shortening (0.89+/-0.71 vs -1.39+/-0.94, p=0.046) and inferior wall chordal shortening (-1.68+/-1.11 vs -2.43+/-0.74, p=0.014) and higher Killip class (1.3+/-0.8 vs 2.4+/-1.4, p=0.002) than without precordial ST segment depression patients. CONCLUSION: In conclusion acute inferior myocardial infarction with precordial ST depression patients had more extensive myocardial damage with global and inferior left ventricle severe wall motion dysfunction. Therefore, this suggests a worse prognosis in acute inferior myocardial infarction with precordial ST depression than without precordial ST depression patients. We need more aggressive diagnosis and treatment in this patients to prevent extending myocardial damage.
Subject(s)
Humans , Coronary Angiography , Depression , Diagnosis , Electrocardiography , Heart Ventricles , Inferior Wall Myocardial Infarction , Plasma , Prognosis , Retrospective Studies , Thrombolytic TherapyABSTRACT
BACKGROUND: Isoflurane and enflurane have different activity on the cytoplasmic calcium movements of a cardiac muscle cell and a vascular smooth muscle cell. Isoflurane is less depressive in cardiac contraction, and more potent in vasodilation than enflurane. This study is to elucidate the effects of these anesthetics on the ST-segment displacement. METHODS: The anesthesia was induced by the intravenous injection of thiopental (6 mg.kg 1) and pipecuronium (0.1 mg.kg 1). The patients (n=80) undergoing tympanoplasty were randomly allocated to two groups for the maintenance METHODS: Group I was inhaled with isoflurane (1~2%), O2 (2 L.min 1), and N2O (2 L.min 1), Group II, enflurane (1.5~2.5%), O2 and N2O. Continuous electrocardiographic recordings with Holter monitor were made during anesthesia. The recordings were scanned on an Avionics Electrocardioscanner with particular emphasis on ST-segment changes. The criteria describe an episode as ST-segment displacement greater than or equal to 0.1 mV measured 80 ms from J-point lasting for more than 1 minutes. Mean heart rate was calculated. Results were categorized as induction, maintenance, and emergence, and inferred from unpaired t-test, x2-test, and Mann-Whitney U test with p<0.05 considered significant. RESULTS: Enflurane had higher incidence of ST-segment depression during induction, more maximally depressed ST-segment during maintenance and slower heart rate during induction and maintenance than isoflurane. CONCLUSION: It could be suggested that enflurane make stronger influence on the ST-segment depression than isoflurane. However, the clinical significance remains to be studied.
Subject(s)
Humans , Anesthesia , Anesthetics , Calcium , Cytoplasm , Depression , Electrocardiography , Enflurane , Heart Rate , Incidence , Injections, Intravenous , Isoflurane , Muscle, Smooth, Vascular , Myocytes, Cardiac , Pipecuronium , Thiopental , Tympanoplasty , VasodilationABSTRACT
BACKGROUND: Paroxysmal supraventricular tachycardia(PSVT) is frequently associated with ST segment depression or T-wave inversion. However, the mechanism of ST-T changes in the context of various mechanisms of PSVT is not clear. The purpose of this study was to evaluate the prevalence of ST depression or T-wave inversion during PSVT and determine whether these changes are related to the mechanism of PSVT or the rate of the tachycardia. METHODS: Twelve-lead electrocardiograms were recorded during sinus rhythm and during PSVT in 163 patients who underwent an electrophysiologic study for ablation. Tachycardia cycle length, presence of ST depression or T-wave inversion during PSVT and the mechanism of tachycardia were evaluated. Significant ST depression was defined as at least 1mm horizontal or downsloping depression, measured 80ms after the J point and T-wave inversion as inversion of T-wave which was positive in the same lead during sinus rhythm. RESULTS: 1) The mechanism of PSVT analysed for ST segment depression was atrioventricular nodal reentry tachycardia in 60 cases and atrioventricular reentry tachycardia in 111 cases. The mean tachycardia cycle length was 373.8+/-68.0 msec. 2) ST depression and T-wave inversion was observed during PSVT in 56%(96/171) and 45%(77/171) of cases, respectively. 3) Tachycardia cycle length, degree of ST depression and number of leads with ST depression are not different according to the mechanism of PSVT. 4) ST depression and tachycardia cycle length had significant correlation, especially in atrioventricular reentry tachycardia. 5) Leads with T-wave inversion during tachycardia was observed more frequently in atrioventricular reentry tachycardia than atrioventricular nodal reentry tachycardia(p<0.05), but no difference between manifest and concealed bypass tract. CONCLUSIONS: ST segment depression is rate-related phenomenon and not different according to the mechanism of PSVT. Leads with T-wave inversion during tachycardia was observed more frequently in atrioventricular reentry tachycardia.
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Humans , Depression , Electrocardiography , Prevalence , Tachycardia , Tachycardia, Atrioventricular Nodal Reentry , Tachycardia, SupraventricularABSTRACT
BACKGROUND: Inferior myocardial infarctions account for 40-50% of all acute myocardial infarctions and are generally viewed as having a more favorable prognosis than anterior wall infarctions. However, nearly 50% of patients suffering inferior infarction will have complications such as heart block, concomitant precordial ST-segment depression and right ventricular infarction or distinguishing features associated with an increased mortality that will substantially alter an otherwise favorable prognosis. METHODS: Clinical characteristics, electrocardiograms, and angiographic findings of coronary artery were viewed in 47 patients with inferior myocardial infarction. Significant ST-segment change was defined as > or =0.1mV horizontal or down sloping depression in acute inferior myocardial infarction patients with ST-segment elevation on leads II, III, aVF measured with reference to the TP segment, 80ms after J point. A group=no precordial ST-segment depression. B group=sum of ST-segment depression in leads V1 to V3 equal to or more than the sum of ST-segment depression in leads V4 to V6. C group=maximal precordial ST-segment depression in leads V4 to V6. RESULTS: 1) Incidence of multi-vessel disease in group A and in group B were 23% and 22%, respectively, compared with 60% for those of group C(p0.05). CONCLUSION: The patients with acute inferior myocardial infarction with the maximal ST-segment depression in leads V4 to V6 would be at high risk for congestive heart failure and multi-vessel disease.
Subject(s)
Humans , Coronary Vessels , Depression , Electrocardiography , Heart Block , Heart Failure , Incidence , Infarction , Inferior Wall Myocardial Infarction , Mortality , Myocardial Infarction , PrognosisABSTRACT
BACKGROUND: Exercise induced ST-segment depression in patients after coronary angioplasty is frequently observed but the mechanism responsible for exercise induced myocardial ischemia early after successful coronary angioplasty is poorly understoodd. The object of this study is to investigate potential determinants of this phenomenon by analizing the clinical, exercise testing, and angiographic characteristics in patients with exercise induced ST-segment depression. METHODS: The study group comprised 13 patients with exercise induced ST-segment depression(Positive group,M:12, mean age:59+/-9year) and 26 patients without exercise induced ST-segment depression(Negative group, M; 22, mean age; 55+/-13 year) after succeessful coronary angioplasty in single vessel disease. We compared preangioplasty clinical, angiographic, and hemodynamic variables in group with positive and negative results on exercise testing after successful PTCA. RESULTS: 1) Clinical characteristics: The initial diagnosis were acute myocardial infarction in 5, unstable angina in 8 patients at positive group, and 16 and 10 patients at negative group, respectively. There were no significant different in initial diagnosis, risk factor for coronary artery disease, and medication used before exercise test at between two groups. 2) Cornary angiography and PTCA: The maximal ballooning size were significantly smaller in positive group than negative group(2.7+/-0.5 vs 3.1+/-0.4mm, 2.9+/-0.4mm, vs 3.2+/-0.4mm, respectively(p<0.05) but there were no significantly different in ejection fraction, end-diastolic volume, end-systolic volume before PTCA. degree of stenosis of lesion before and after PTCA, total ballooning time, balloon pressure, lesion site and infarction relation of lesion at between two groups. 3) Exercise test: The mean time from angioplasty to the performance of exercise testing were 9.5+/-4.0 days in positive group and 6.1+/-4.5 days in negative group. The mean depression of ST-segment was 1.5+/-0.5mm and was predominantly noted in lateral leads(V4-6)(9/13:69%). There were no significantly different in total exercise time, rate-pressure product, and metabolic equivalents-exercise time at positive and negative group. But positive results at follow up exercise test were significantly higher in positive group(p<0.05). CONCLUSION: There were no definite determinating factors for exercise induced ST-segment depression early after successful coronary angioplasty by analizing the clinical, angiographic, and exercise testing variables. The pathophysiologic mechanism of this findding remain to be elucidated, especially for association of microvascular functional alternation.
Subject(s)
Humans , Angina, Unstable , Angiography , Angioplasty , Constriction, Pathologic , Coronary Artery Disease , Depression , Diagnosis , Exercise Test , Follow-Up Studies , Hemodynamics , Infarction , Myocardial Infarction , Myocardial Ischemia , Risk FactorsABSTRACT
BACKGROUND: Reciprocal ST-segment depression in precordial leads is a common finding in acute inferior myocardial infarction. The responsible mechanism and the significance of this finding, however, are still controversial. METHODS: Clinical characteristics, serial eletrocardiograms, angiographic findings of coronary artery and left ventricle were reviewed in 33 patients with acute inferior myocardial infarction. Reciprocal ST-segment depression was defined as ST-segment depression > or =1.0mm in two or more adjacent chest leads, I and aVL in patients with acute inferior myocardial infarction showing ST-segment elevation in II, III, aVF. Coronary angiography and left ventriculography were performed 15,2+/-16.9 hours after arrival. RESULTS: Eleven patients did not have reciprocal ST-segment depression(group A) and 22 patients had reciprocal ST-segment depression(group B). There was no significant difference in the demographic data of the patients except age and peak CK-MB, which were significantly higher in group B than group A. Left anterior descending coronary artery(LAD) stenosis was significantly more frequent in group B than group A(54.5% vs 18.2%, p<0.05). However the distribution of left ventricular regional wall motion abnormality and global ejection fraction showed no difference between two groups. In addition, there was no difference in in-hospital complications. CONCLUSIONS: These results suggest that reciprocal ST-segment depression in acute inferior myocardial infarction can be explained by anterior ischemia due to concomitant LAD stenosis in some cases, but its clinical significance is limited at least in terms of in-hospital complications.