ABSTRACT
The incidence of acute myocardial infarction (AMI) is increasing. Acute papillary muscle rupture is one of the serious and rare mechanical complications of AMI, which occurs mostly in inferior and posterior myocardial infarction. A patient with acute inferior myocardial infarction developed pulmonary edema and refractory shock, followed by cardiac arrest. After cardiopulmonary resuscitation (CPR), revascularization of criminal vessels was carried out by emergency percutaneous transluminal coronary angioplasty (PTCA) under the support of intra-aortic balloon pump (IABP) and extra corporeal membrane oxygenation (ECMO). Although the patient was given a chance for surgery, his family gave up treatment due to unsuccessful brain resuscitation. It reminds that mechanical complications such as acute papillary muscle rupture, valvular dysfunction and rupture of the heart should be highly suspected when cardiogenic pulmonary edema and cardiogenic shock are difficult to correct in acute inferior myocardial infarction. Echocardiogram and surgery should be put forward when revascularization of criminal vessels is available.
Subject(s)
Humans , Inferior Wall Myocardial Infarction/complications , Papillary Muscles/surgery , Pulmonary Edema , Myocardial Infarction/surgery , Shock, CardiogenicABSTRACT
Early accurate detection of inferior myocardial infarction is an important way to reduce the mortality from inferior myocardial infarction. Regrading the existing problems in the detection of inferior myocardial infarction, complex model structures and redundant features, this paper proposed a novel inferior myocardial infarction detection algorithm. Firstly, based on the clinic pathological information, the peak and area features of QRS and ST-T wavebands as well as the slope feature of ST waveband were extracted from electrocardiogram (ECG) signals leads Ⅱ, Ⅲ and aVF. In addition, according to individual features and the dispersion between them, we applied genetic algorithm to make judgement and then input the feature with larger degree into support vector machine (SVM) to realize the accurate detection of inferior myocardial infarction. The proposed method in this paper was verified by Physikalisch-Technische Bundesanstalt (PTB) diagnostic electrocardio signal database and the accuracy rate was up to 98.33%. Conforming to the clinical diagnosis and the characteristics of specific changes in inferior myocardial infarction ECG signal, the proposed method can effectively make precise detection of inferior myocardial infarction by morphological features, and therefore is suitable to be applied in portable devices development for clinical promotion.
Subject(s)
Humans , Algorithms , Databases, Factual , Electrocardiography , Inferior Wall Myocardial Infarction , Support Vector MachineABSTRACT
Belching is a ubiquitous symptom in clinical practice. It could be due to gastrointestinal disease or behavioral, functional and physiological causes. It’s association with acute myocardial infarction, more frequently, with inferior myocardial infarction, has been well established. But exertional belching as a cardinal symptom of coronary artery disease is not well documented and its presence is not mentioned in any standard textbooks. It is rarely reported in the literature. Here we present a female diabetic, who presented with exertional belching as a lone complaint. She was confirmed to have significant coronary artery disease necessitating an intervention. So it may be prudent if clinicians are aware of the fact that exertional belching could be of cardiac origin and needs further evaluation and intervention.
ABSTRACT
Inferior myocardial infarction is an acute ischemic heart disease with high mortality, which is easy to induce life-threatening complications such as arrhythmia, heart failure and cardiogenic shock. Therefore, it is of great clinical value to carry out accurate and efficient early diagnosis of inferior myocardial infarction. Electrocardiogram is the most sensitive means for early diagnosis of inferior myocardial infarction. This paper proposes a method for detecting inferior myocardial infarction based on densely connected convolutional neural network. The method uses the original electrocardiogram (ECG) signals of serially connected Ⅱ, Ⅲ and aVF leads as the input of the model and extracts the robust features of the ECG signals by using the scale invariance of the convolutional layers. The characteristic transmission of ECG signals is enhanced by the dense connectivity between different layers, so that the network can automatically learn the effective features with strong robustness and high recognition, so as to achieve accurate detection of inferior myocardial infarction. The Physikalisch Technische Bundesanstalt diagnosis public ECG database was used for verification. The accuracy, sensitivity and specificity of the model reached 99.95%, 100% and 99.90%, respectively. The accuracy, sensitivity and specificity of the model are also over 99% even though the noise exists. Based on the results of this study, it is expected that the method can be introduced in the clinical environment to help doctors quickly diagnose inferior myocardial infarction in the future.
ABSTRACT
Objective To investigate the prognostic risk factors of patients with acute inferior myocardial infarction and intra-operative occurrence of ventricular fibrillation (VF) when undergoing emergency percutaneous coronary intervention (PCI). Methods The data of 52 patients with acute inferior myocardial infarction treated in Cangzhou City People's Hospital from May 2016 to May 2018 were retrospectively analyzed, and they were divided into poor prognosis group (19 cases) and good prognosis group (33 cases) according to whether cardiovascular events occurred during 1 year of follow-up. The patients' gender, age, smoking or not, histories of diabetes, hypertension, hyperlipidemia, and the results of well performed color echocardiography within recent 3 days, such as left ventricular ejection fraction (LVEF), cardiac infarction size (IS), and coronary Gensini score were recorded in the two groups; the indicators with statistical significance in univariate analysis were included in the multivariate logistic regression analysis to screen out the prognostic risk factors of patients with acute inferior wall myocardial infarction undergoing emergency PCI and occurrence of intra-operative VF; Receiver operating characteristic (ROC) curve was drawn to evaluate the values of coronary Gensini score and IS in predicting intraoperative occurrence of VF in patients with acute inferior wall myocardial infarction undergoing emergency PCI. Results During 1-year follow-up, 19 of 52 patients with acute inferior myocardial infarction occurred VF, the incidence being 36.5%. The univariate analysis showed that the IS and Gensini score in poor prognosis group were significantly higher than those in the good prognosis group [IS: (3.2±0.2)% vs. (2.5±0.4)%, Gensini score: 98.8±12.5 vs. 85.7±8.4, both P < 0.05], the LVEF level was significantly lower in the poor prognosis group than that in the good prognosis group (0.37±0.08 vs. 0.46±0.11, P < 0.05). The multivariate Logistic regression analysis showed that IS [odds ratio (OR) = 5.016] and coronary Gensini score (OR = 2.415) were the risk factors of occurrence of cardiovascular events after surgery in patients with acute inferior myocardial infarction and intra-operative VF when undergoing PCI (P < 0.05). The ROC curve analysis showed that IS and coronary Gensini scores had certain predictive values for the prognosis of patients with acute inferior myocardial infarction and occurrence of intra-operative VF when undergoing emergency PCI, the area under the ROC curve (AUC) was 0.863 and 0.597, respectively, indicating that IS had a medium predictive value, while the value of coronary Gensini score was lower, when the IS optimal cut off value was 3.0, the sensitivity was 89.4% and the specificity was 88.0%. Conclusion High IS and Gensini score are the risk factors of prognosis of patients with acute inferior myocardial infarction and intra-operative occurrence of VF when undergoing emergency PCI.
ABSTRACT
Objective To explore the possible causative factors of appearance of ventricular fibrillation (VF) during emergency percutaneous coronary intervention (PCI) in patients with acute inferior myocardial infarction. Methods Five hundred and seventy two patients with acute inferior myocardial infarction who underwent emergency PCI 24 hours after onset from May 2016 to May 2018 in Cangzhou People's Hospital were enrolled, they were divided into a VF group (52 cases) and a non-VF group (NVF, 520 cases) according to whether VF occurred or not during PCI. The differences in clinical data, characteristics of coronary artery disease and coronary artery score (Gensini score) between the two groups were compared; multivariate Logistic regression analysis was used to analyze the risk factors related to the occurrence of VF during emergency PCI; the receiver operating characteristic curve (ROC) was drawn to evaluate the efficacy of each risk factor. Results There were no statistical significant differences in sex, age, past histories of drinking alcohol, smoking, hypertension, diabetes, previous use of β blockers, aspirin, the peak values at admission of systolic blood pressure, heart rate, creatine kinase isoenzyme (CK-MB) and cardiac troponin I (cTnI), etc between the two groups (all P > 0.05). The proportions of patients with grade 0 blood flow in myocardial infarction thrombolysis (TIMI) before recanalization, with high thrombus load, criminal vessels being right coronary artery (RCA) and proximal segment of RCA, Gensini score in VF group were significantly higher than those in NVF group [TIMI 0: 80.8% (42/52) vs. 58.1% (302/520), high thrombus load: 71.2% (37/52) vs. 58.1% (302/520), criminals being RCA: 84.6% (44/52) vs. 73.7% (383/520), the occlusion site of infarction-related artery (IRA) being the proximal segment of RCA: 61.5% (32/52) vs. 41.2% (214/520), Gensini scores: 93.84±16.48 vs. 61.37±20.01, all P < 0.05]. The multiple logistic regression analysis showed that the risk factors for VF occurrence during emergency PCI for patients with acute inferior myocardial infarction included the criminals being RCA [odds ratio (OR) = 1.967, 95% confidence interval (95% CI) = 1.696-3.015, P =0.032], TIMI blood flow grade 0 before re-canalization (OR = 3.032, 95%CI = 1.248-3.675, P = 0.043), the occlusion site of infarction-related artery (IRA) being the proximal segment of RCA (OR = 2.288, 95%CI = 1.458-3.895, P =0.024), Gensini score (OR = 6.558, 95%CI = 2.168-13.359, P = 0.001] and high thrombus load (OR = 1.781, 95%CI =1.016-3.017, P = 0.033); they all were risk factors of occurrence of ventricular fibrillation during emergency PCI in patients with acute inferior myocardial infarction (all P < 0.05). ROC curve analysis showed that TIMI blood flow grade 0 before re-canalization, Gensini score and higher thrombus load had certain predictive value for VF occurrence during emergency PCI for acute inferior wall myocardial infarction; the area under ROC curve (AUC) was 0.613, 0.869 and 0.605, and 95% CI was 0.540-0.687, 0.787-0.969 and 0.521-0.675, the P value was 0.007, 0.000 and 0.012, respectively, suggesting that Gensini score had moderate predictive value for intra-operative VF, while the predictive values of TIMI blood flow grade 0 before re-canalization and higher thrombus load were relatively low. When the Gensini score had an optimal cutoff value of 96.50, the sensitivity was 85.50% and the specificity was 81.20%. Conclusion The risk factors of VF occurrence in emergency PCI for patients with acute inferior myocardial infarction are criminal vessel RCA, TIMI blood flow grade 0 before re-canalization, IRA occlusion site being proximal segment of RCA, Gensini score and high thrombus load; pre-recanalization TIMI blood flow grade 0, Gensini score and higher thrombus load all have certain predictive value for the occurrence of VF in emergency PCI for acute inferior myocardial infarction.
ABSTRACT
Objective To investigate the preoperative risk factors of occurrence of intra-operative ventricular fibrillation (VF) in patients with acute inferior myocardial infarction undergoing emergency percutaneous coronary intervention(PCI). Methods A retrospective approach was conducted, 572 patients with acute inferior myocardial infarction admitted to Cangzhou City People's Hospital from May 2016 to May 2018 were enrolled, and they were divided into VF group (50 cases) and non-VF group (520 cases) according to whether the intra-operative complication of VF occurred. The clinical data of the two groups of patients were collected, and the related risk factors were analyzed by univariate and multivariate analyses to explore the preoperative risk factors related to VF intra-operative occurrence in patients with acute inferior myocardial infarction undergoing emergency PCI; the receiver operating characteristic (ROC) curve was drawn to evaluate the test efficiencies of all kinds of risk factors. Results The univariate analysis showed that the ratio of Killip > Ⅰ grade, infarct area size/blood potassium concentration (IS/[K]) and symptom onset to balloon dilatation time (SOTBT) in the VF group were significantly higher than those in the non-VF group [Killip > Ⅰ grade:36.5% (19/52) vs. 24.0% (125/520), IS/[K]: 3.2±0.3 vs. 2.5±0.8, SOTBT (hours): 6.3 (2.1, 8.0) vs. 4.6 (1.8, 6.5)], the differences were statistically significant (all P < 0.05); the T wave peak to T end interval/QT interval (Tp-e/QT) and blood potassium level of the VF group were significantly lower than those of the non-VF group [Tp-e/QT: 0.3±0.1 vs. 0.4±0.1; blood potassium (mmol/L): 2.8±0.5 vs. 4.1±1.2, both P < 0.05]. Multivariate logistic regression analysis showed that the SOTBT > 6 hours [odds ratio (OR) = 8.337], Killip >Ⅰ grade (OR = 1.721), hypokalemia (OR = 1.031) and high IS/[K] (OR = 9.167) were independent risk factors for intra-operative occurrence of VF in patients with acute inferior myocardial infarction during emergency PCI (all P < 0.05). ROC curve analysis showed that the area under the ROC curve (AUC) of serum potassium, IS/[K], SOTBT > 6 hours and Killip > Ⅰ grade for predicting the intra-operative occurrence of VF during emergency PCI for patients with acute inferior myocardial infarction had certain values, their AUC were 0.633, 0.837, 0.821, 0.682, respectively, suggesting that IS/[K] and SOTBT > 6 hours had moderate predictive values, and serum potassium, Killip > Ⅰ grade had relatively low predicative values; when the optimal cut-off value of IS/[K] was 2.8, the sensitivity was 85.5% and the specificity was 80.0%. Conclusion SOTBT > 6 hours, Killip > Ⅰ grade, hypokalemia, and high IS/[K] are independent risk factors of intra-operative occurrence of VF in patients with acute inferior myocardial infarction undergoing emergency PCI.
ABSTRACT
Objective To investigate the clinical significance of ambulatory blood pressure monitoring in short-term prognosis of acute inferior myocardial infarction patients .Methods A total of 80 patients with acute inferior myocardial infarction received 24 hours ambulatory blood pressure monitoring after enrolled .According to the results of 24 hours ambulatory blood pressure monito-ring ,eligible patients were divided into dipper model group(n=29) and non-dipper model group(n=51) .Clinical information was collected and all patients were followed-up for major adverse cardiovascular events (MACE) .Results The rate of intravenous thrombolysis in dipper model group was significantly higher than that in non-dipper model group(t=4 .120 ,P=0 .021) .Night mean systolic blood pressure and night mean diastolic blood pressure were all significantly lower in dipper model group than in non-dipper model group(t=2 .032 ,P=0 .040 ;t=3 .175 ,P=0 .002) .The rate of cumulative MACE in non-dipper model group was significant-ly higher than that in dipper model group(t=2 .626 ,P=0 .041) .Multivariate logistic regression analysis showed that ,daytime mean systolic blood pressure(<90 mm Hg) was independent risk factor of MACE(P=0 .018 ,OR=1 .298) ,dipper model blood pressure (P=0 .019 ,OR=0 .769) and intravenous thrombolysis(P=0 .007 ,OR=0 .520) were protective factors for MACE .Conclusion Parameters of ambulatory blood pressure monitoring are closely correlated with prognosis of acute inferior myocardial infarction pa-tients ,and the change of blood pressure model is an important factor for short-term prognosis .
ABSTRACT
The incidence of multivessel coronary artery ectasias (CAEs) among patients undergoing coronary artery angiography is very rare. All three coronary vessels can be affected by CAE, but most patients have an isolated arterial ectasia, commonly the right coronary artery. In this report we present two cases with inferior myocardial infarction that was likely caused by thrombotic occlusion of CAEs.
Subject(s)
Humans , Angiography , Coronary Artery Disease , Coronary Vessels , Dilatation, Pathologic , Incidence , Inferior Wall Myocardial InfarctionABSTRACT
Objective To investigate the association between chest ST segment descent in patients with acute inferior myocardial infarction (AIMI) and myocardial infarction in other area, QT dispersion, severe auriculoventricular block (AVB) serious ventricular arrhythmia. Methods According to persistent time of chest lead ST segment descent,74 patients of acute inferior myocardial infarction with chest lead ST segment descent were divided into 2 groups: ≥24 h (group Ⅰ ,44 cases), ＜ 24 h (group Ⅱ ,30 cases). The occurrence of other areas of myocardial infarction, QTd, auricular-ventricular block and serious ventricular arrhythmia were compared between the two groups. Results Chest ST segment descent occurred in 33 cases in group Ⅰ (75%) ,in 7 cases in group Ⅱ ( 23% ), with significantly difference between the two groups ( χ2 = 19. 17, P ＜ 0. 01 ). QTd was (74. 77 ± 23.28) ms in group Ⅰ which was significantly higher than that of (50. 00 ± 11:45 ) ms in group Ⅱ ( t =5.39,P ＜0. 01 ). Auricular-ventricular block (grade Ⅱ and Ⅲ ) occurred in 20 cases in group Ⅰ (45%),and in 5 cases in group Ⅱ ( 17% ), with significant difference between the two groups (χ2 = 9.43, P ＜ 0. 05 ). Twentyone cases with serious ventricular arrhythmia occurred in group Ⅰ (48%) ,which was significantly higher than that in group Ⅱ (4 cases, 13% ) ( χ2 = 6. 61, P ＜ 0. 01 ) . Conclusion When persistent time of acute inferior myocardial infarction with chest lead ST segment descent is longer than 24 hrs, the area of myocardial infarction is more extensive, QT dispersion increases, the occurrence of serious ventricular arrhythmia and auricularventricular block also significantly increase.
ABSTRACT
Objecfive To study the clinical characteristics of acute inferior myocardial infarction.Methods 100 patients with acute inferior infarction were divided into 2 groups according to coronary angiography:group A (n=76) with right coronary artery occlusion;group B(n=24) with left circumflex artery occlusion.Results The frequencies of Electrocardiogram(ECG) ST segment elevation ST Ⅲ>ST Ⅱ and ST segment depression STAVL>STI in group A was significantly higher than that in group B(P<0.05);The frequency of ECG ST segment elevation STⅢ<STⅡ in group A wag significantly lower than that in group B(P<0.01);The frequency of ECG STV4R elevation >O.1 mV in group A was significantly higher than that in group B(P<0.05);The number of ECG with precor-dial lcads V1～6 ST segment depression >0.1 mv with lesion of left anterior descending coronary was more significant than that without precordial Vl-6 leads ST segment depression (P<0.05).Left ventricular ejection fraction (LVEF)(51%±14%) in group A was significant lower than that in group B(57%±10%)(P<0.05);The patients in group A with right ventricular infarction were more significant than those in group B(P<0.05);The total hospital mortality of patients with acute inferior myocardial infarction was 6%,and they were all in group A.But there was no significance between the two groups about cardiogenic shock,heart failure,Ⅱ degree and Ⅲ degree atrial ventricular b1ock,ventrieular tachycardia/ventrieular fibrillation and the hospital mortality.The mortality with cardiogenic shock was 83.3%.Conclusion The changes of ECG ST segment in Ⅲ,Ⅱ,Ⅰ,AVL and V4R leads can predict relatedinfarct coronary artery with acute inferior myocardial infarction.The patients with precordial Vl～6 leads ST segment depression indicates lesion of LAD.The LVEF of patients with RCA occlusion is lower than that with LCX occlusion. The primary cause of death is eardiogenic shock.
ABSTRACT
Nearly 50% of patients suffering inferior myocardial infarction will have complications or distinguishing features associated with an increased mortality. This study aimed to identify dominant risk factors related to re-occurrence of acute coronary events in patients with inferior myocardial infarction. This historical cohort included patients with inferior myocardial infarction who received fibrinolytic therapy at emergency department of National Cardiovascular Center Harapan Kita, Jakarta during 2001 to 2004 and was followed-up for two years. Patients with previous myocardial infarction, left bundle branch block, ventricular rhythm, and ventricular pacing were excluded. QRS distortion is ratio between J-point and R wave more than 50% at 2 or more inferior leads. Re-occurrence of acute coronary events is incident of myocardial infarction and unstable angina pectoris. Of 181 subjects with inferior AMI, there were 21 (11.6%) incidents of acute coronary event. Those who had positive than negative QRS distortion had almost three-fold increased risk for re-occurrence of acute coronary events [adjusted relative risk (RRa) 2.88; 95% confidence interval (CI) = 1.05 – 7.90]. In term of TIMI risk score, those with higher than lower risk score had 6.7 times higher risk to be re-occurrence of acute coronary events (RRa = 6.66; 95% CI = 1.94 – 22.92). However, those who had than did not have successful fibrinolysis had 57% lower risk to be re-occurrence of acute coronary event (RRa = 0.43; 95% CI = 0.18 – 1.05; P = 0.065). Re-occurrence acute coronary events were related to QRS distortion, TIMI risk score, and successful fibrinolysis.
Subject(s)
Inferior Wall Myocardial Infarction , FibrinolysisABSTRACT
BACKGROUND AND OBJECT: We intended to assess the characteristics of ST segment deviation in lateral leads(aVL, I, V5, V6) in patients with acute inferior myocardial infarction(AIMI) and find out the relationship with culprit arteries. MATERIALS AND METHOD: The subjects were 51 patients diagnosed as AIMI by standard electrocardiogram, cardiac enzymes and typical chest pain. Subjects were devided into two groups by angiographically proven culprit arteries ; left circumflex artery(LCx) group and right coronary artery(RCA) group. We compared the frequencies of ST segment depression more than 1 mm and less than 1 mm in aVL and I, and ST segment elevation more than 0.5 mm and less than 0.5 mm in V5 and V6 in each culprit artery group. RESULTS: Among 51 patients with AIMI, 42 were RCA group and 9 were LCx group. The frequency of ST segment depression more than 1 mm in aVL was 44% in LCx group and 71% in RCA group(p=0.140). 11% of LCx group and 43% of RCA group showed more than 1 mm ST segment depression in lead I (p=0.128). 56% of LCx group showed more than 0.5 mm ST segment elevation in V5 and V6 and 81% of RCA group showed less than 0.5 mm ST segment elevation in V5 and V6 (p=0.036). CONCLUSION: Culprit arteries in patients with AIMI and ST segment deviation in V5 and V6 are significantly related with each other. ST segment elevation more than 0.5 mm in V5 and V6 was predominantly found in LCx group than RCA group. Observation for ST segment deviation in lateral precordial lead V5 and V6 would be important in predicting the culprit artery in AIMI.
Subject(s)
Humans , Arteries , Chest Pain , Depression , Electrocardiography , Inferior Wall Myocardial InfarctionABSTRACT
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 AND OBJECTIVES: Eectrocardiogram (ECG) may provide valuable informations regarding the infarct-related artery (IRA), which may be of guidance in selecting the therapeutic modality. ST segment elevation in inferior leads usually indicates occlusion of right coronary artery, less often left circumflex coronary artery or rarely occlusion of left anterior descending coronary artery may be the cause. We are to determine whether the initial ECG can differentiate the right coronary artery (RCA) or left circumflex artery (LCx) occlusion in acute inferior myocardial infarction (IMI). MATERIALS AND METHOD: We compared retrospectively the ECG recorded within 12 hours from the onset of chest pain with coronary angiographic findings in 85 patients (34% of all 250 patients) having electrocardiographic criteria for IMI. RESULTS: 1) Angiographic characteristics. Of the 85 patients, IRA was RCA in 65 (76%) (38[58%] proximal, 27[42%] distal to first right ventricular branch), and LCx in 20 (24%) (nine[45%] proximal to first obtuse marginal branch or involving a high first marginal branch, eleven[55%] distal obstruction). RCA dominance was more common in RCA occlusion group (100% vs 80%, p=0.001), and LCx dominance in LCx occlusion group (15% vs 0%, p=0.001). No significant difference was noted between two groups regarding vessels diseased, involvement of left anterior descending coronary artery and contralateral artery (RCA or LCx), location of the lesion. 2) Electrocardio-graphic characteritics. Lateral limb leads (I, aVL) :ST segment depression (> or = 1 mm) was more common in RCA occlusion group (82% vs 45%, p=0.001). Isoelectric ST segment in I was more common in LCx occlusion group (100% vs 15%, p=0.001). Left precordial leads (V(5,6)) :ST segment elevation (> or = 1 mm) was more common in LCx occlusion group (60% vs 15%, p=0.001). Isoelectric ST segment was more common in RCA occlusion group (57% vs 20%, p=0.004). ST segment depression (> or = 1 mm) was not different between two groups. Right precordial leads (V(1-4)) :ST segment changes were not different between two groups. Lead I and left precordial leads (V(5,6)) :Isoelectric ST segment in lead I and ST segment elevation (> or = 1 mm) in V(5) or V(6) was more common in LCx occlusion group (60% vs 5%, p<0.05, sensitivity 60% specificity 95% positive/negative predictive value 80%/89%, test accuracy 87%). Amplitude of R wave in V(1) :Amplitude of R wave in V was greater in LCx occlusion group (3.60+/-1.42 mm vs 2.20+/-1.42 mm, p<0.05). CONCLUSION: The initial electrocardiogram was useful in differentiating LCx occlusion from RCA occlusion in patients with IMI. Absence of ST segment depression in I and aVL, and ST segment elevation in V(5,6), isoelectric ST segment in I, tall R wave in V(1) were significantly more common in LCx occlusion.
Subject(s)
Humans , Arteries , Chest Pain , Coronary Vessels , Depression , Electrocardiography , Extremities , Inferior Wall Myocardial Infarction , Retrospective Studies , Sensitivity and SpecificityABSTRACT
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: From January 1991 to December 1994, 38 patients with acute inferior myocardial infarction were treated at the Department of Internal Medicine in Kyung Hee University Hospital. Clinical characteristics, serial electrocardiograms, and angiographic findings of coronary artery and left ventriculography, echocardiography were reviewed. Reciprocal ST-segment depression was defined as ST-segment depression>or=1.0mm in two or more adjacent precordial leads(V1-V3) in patients with acute inferior myocardial infarction showing ST-segment elevation in II, III, aVF. Coronary angiography and echocardiography were performed within 24 hours from admission. In this study, angiographic distribution score was used to define the perfusion territory causing inferior ischemia. RESULTS: 1) The summation of ST-segment elevation in II, III, aVF leads was significantly more higher in group H than group A (P0.05). 3) There were no evidence of anterior wall motion abnormality in two groups. CONCLUSIONS: Our results suggest that the S'I'- segment depression on the precordial leads in acute myocardial infarction can be explained mainly by benign reciprocal electrical change.
Subject(s)
Humans , Coronary Angiography , Coronary Vessels , Depression , Echocardiography , Electrocardiography , Inferior Wall Myocardial Infarction , Internal Medicine , Ischemia , Myocardial Infarction , PerfusionABSTRACT
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: 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.
Subject(s)
Humans , Constriction, Pathologic , Coronary Angiography , Coronary Stenosis , Coronary Vessels , Depression , Heart Ventricles , Inferior Wall Myocardial Infarction , Ischemia , ThoraxABSTRACT
To evaluate the clinical significance of atrioventricular blocks in acute inferior myocardial infarction, we reviewed the clinical recordes of 75 patients who were diagnosed as acute inferior myocardial infarction with or without associated atrioventricular conduction blocks and compared the difference in clinical observation and laboratory data including coronary angiography between these two groups of patients. We also followed the clinical courses of atrioventrticualr block during admission among the patients with blocks. 1) 40% of 75 patients had atrioventricualr block associated with acute inferior myocardial infarction and there were 7 first-degree, 8 second-degree and 15 third-degree atrioventricular blocks. 2) There was no statistically significant differences between two groups in mean age ; Killip classification : incidence of previous prodromal angina ; incidende of associated initial symptoms such as dyspnea, nausea, and syncope ; risk factors such as smoking, hypertension and previous muocardial infarction and incidence of complication such as ventricular arrhythmias and heart faliure. 3) The peak serum CK(1,442.9+/-1,703.6 vs. 1,942.8+/-2,022.9IU/L, P<0.01)and LDH(1,014.7+/-429.7 vs. 1,579.2+/-1,544.9 IU/L, P<0.01) levels were significantly higher in the patients group with atrioventricualr blocks than in the patient grouop without blocks. 4) Left ventricualr resting ejection fraction obtained by radinuclide geted blood pool heart scan was significantly less in the patient group with atrioventricular blocks than in the patient group without blocks. 5) The prevalence of multivessel disease and that of associated left anterior descending artery lesion showe no differences between two patient groups. 6) Hospatal mortality of two patient groups were 9.8% and 16.6% respectively and had no statistical significance. 7) Among the patients who had associated atrioventricualr blocks, 70% of patients showed temporary course of block for mean 4.8days, and 6.7% developed permanent first degree block.