Acute myocardial infarction in a young woman with normal coronary arteries and myocardial bridging

Myocardial bridging (MB) is defined as an intramural segment of a coronary artery that normally courses epicardially. MB is usually a benign condition; however, some cases resulting in myocardial ischaemia, infarction and sudden death have been reported. We describe a case of myocardial infarction related to MB in a young healthy woman with no risk factors for coronary artery disease. The bridge was demonstrated in detail by coronary CT angiography using multiplanar reconstruction and three-dimensional volume-rendered techniques.     

Marked 99mTc-PYP myocardial accumulation immediately after reperfusion in a patient with acute myocardial infarction

We reported a case of a 72-year-old man with chest pain. An electrocardiogram showed ST segment elevation in I, II, III, aVL, aVF and V1-6 leads. 99mTc-tetrofosmin myocardial SPECT showed defect in the anterior, septal, apical and inferior walls. Coronary angiography showed 99% stenosis of the proximal right coronary artery and total occlusion of the midsegment of the left anterior descending coronary artery. Therefore, direct PTCA was performed for each lesion to achieve reperfusion. We didnt's see reperfusion injury during PTCA of the left coronary artery. On the other side, we saw severe reperfusion injury, such as slow-flow, arrhythmia and falling blood pressure during PTCA of the right coronary artery. After four hours, 99mTc-PYP myocardial SPECT showed marked uptake in the apical and inferior walls, and mild uptake in the anterior and posterior walls. After three days, severely-reduced uptake of 99mTc-PYP in the apex was noted, and mild uptake in the mid-portion of the anterior wall and the mid-portion of the inferior wall. Though reperfusion injury was seen, three was mild myocardial uptake of 99mTc-PYP in the area of the right coronary artery. On the other side, despite no reperfusion injury, there showed marked uptake during the acute phase and defect during the subacute phase in the area of the left coronary artery. Wall motion of the left ventricle was normal in the area of the right coronary artery and akinesis was seen on the left. These findings suggest that 99mTc-tetrofosmin and 99mTc-PYP myocardial SPECT are useful for visualization of reperfusion injury during the acute phase and for estimation of function during the chronic phase, better even than electrocardiogram or coronary angiography.     

Acute myocardial infarction during adenosine myocardial perfusion imaging

Journal of Nuclear Cardiology -     

Detection of culprit lesion in patients with unstable angina pectoris by using ATP thallium-201 myocardial SPECT

The purpose of this study is to determine the diagnostic accuracy for detection of culprit lesions in patients with unstable angina. Both ATP 201Tl SPECT and coronary angiography were performed in 51 patients with unstable angina pectoris within a week since the last attack. SPECT images were divided into 17 segments and the regional uptakes were scored semiquantitatively (0 = normal to 3 = no activity) and compared with the coronary angiographic findings. ATP 201Tl SPECT revealed decreased uptakes in 54 of 56 culprit lesions. The sensitivity, specificity and accuracy for detection of culprit lesions were 96.4%, 89.5% and 92.4%, respectively. Although adverse effects during ATP administration were complicated in 28 (54.9%) patients, all the complications were mild and resolved within two minutes. ATP 201Tl SPECT is sensitive and reliable method for detecting culprit lesions and can be performed safely even at acute phase in patients with unstable angina pectoris.     

Effects of preinfarction angina on myocardial injury in patients with acute myocardial infarction: a study with resting 123I-BMIPP and 201T1 myocardial SPECT.

METHODS: Recent studies have suggested that patients with preinfarction angina have smaller infarcts and a better in-hospital outcome than those without angina. The mechanisms responsible for limitation of infarct size in the presence of preinfarction angina are unclear. We examined the effects of preinfarction angina on myocardial injury in patients with the first acute myocardial infarction with resting 123I-15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) 201TI myocardial scanning performed within 1 mo of infarction. RESULTS: Of 136 patients tested, 48 (35%) had preinfarction angina within 72 h before infarction, whereas 88 (65%) did not. BMIPP and 201TI defects were scored in 9 segments of the left ventricle (0 = normal, 1 = mild defect, 2 = moderate defect, 3 = severe defect, and 4 = no uptake). The total defect score was defined as the sum of the defect scores. There was no significant difference in percentage diameters of stenoses of infarct-related arteries, collateral circulation, total defect scores for BMIPP, or 201TI between the groups with and without preinfarction angina. However, the ratio of total defect score for 201TI to that for BMIPP was significantly smaller for patients with than for those without preinfarction angina (0.64 +/- 0.21 versus 0.74 +/- 0.25, respectively; P = 0.007). CONCLUSION: Preinfarction angina did not affect the areas at risk in acute myocardial infarction, as shown by BMIPP defect, but decreased necrotic myocardium in the areas at risk, as shown by 201TI defect, and increased metabolically damaged but viable myocardium, as shown by BMIPP and 201TI mismatch through unidentified mechanisms other than collateral circulation (e.g., ischemic preconditioning).     

Acute myocardial infarction: contrast-enhanced multi-detector row CT in a porcine model

PURPOSE: To assess the role of contrast material-enhanced retrospectively electrocardiographically (ECG) gated multi-detector row computed tomography (CT) in the detection of acute myocardial infarction in a porcine model of total coronary occlusion. MATERIALS AND METHODS: Seven Yorkshire farm pigs were studied with contrast-enhanced retrospectively ECG-gated multi-detector row CT 3 hours after total occlusion of the distal left anterior descending artery (n = 5) or the second diagonal branch (n = 2). Reformatted short-axis end-systolic and end-diastolic CT data sets were assessed for myocardial perfusion deficits, coronary occlusion, and abnormal myocardial wall motion. Perfusion deficits were compared with microsphere-determined blood flow and triphenyltetrazolium chloride (TTC)-stained tissue samples for infarct assessment by using Bland-Altman analysis and analysis of variance. RESULTS: Myocardial perfusion deficits, occlusion of the left anterior descending artery or second diagonal branch, and akinesis of the infarcted segment were identified in all five animals that completed the study. One animal died, and one data set had nondiagnostic image quality. The CT end-diastolic (mean, 16.1% +/- 4.8 [SD]; range, 8.6%-22.2%) and end-systolic (mean, 17.0% +/- 6.4; range, 8.7%-26.8%) volume of perfusion deficit was similar to that of infarcted tissue at TTC staining (mean, 13.6% +/- 6.0; range, 7.8%-30.9%). Infarcted myocardium at CT demonstrated a 76.1% reduction in microsphere-determined blood flow and a significant reduction of myocardial CT attenuation compared with normal myocardium (P <.01). Myocardial wall motion analysis demonstrated absence of systolic wall thickening in infarcted myocardium. CONCLUSION: Multi-detector row CT with retrospective ECG gating permits the detection and further characterization of acute myocardial infarction in a porcine model of complete coronary occlusion.     

Simultaneous assessment of coronary stenosis, myocardial perfusion, and ventricular function in a patient with acute myocardial infarction

Cardiac CT angiography (CTA) is an ideal tool to investigate cardiac and noncardiac causes of acute chest pain. In this case, careful planning of the CTA acquisition and reconstruction limits permitted not only the exclusion of aortic dissection and provided high resolution images of coronary anatomy but also showed a concordant abnormality in myocardial perfusion and ventricular function in the setting of an acute coronary syndrome. Detailed planning of every CTA acquisition reconstruction protocol is essential to obtain the information necessary for clinical decision-making strategies and interventions in the patient with chest pain.     

Acute myocardial infarction complicated by severe left ventricle systolic dysfunction in a young patient after Covid 19 vaccination: a case report

We report the case of a 23 years old patient who developed an acute myocardial infarction one day after his second dose of COVID-19 BIBP vaccination, complicated by severe left ventricle systolic dysfunction with an ejection fraction measured at 32%, associated with left ventricular wall motion abnormalities well evolved under treatment of heart failure with reduced EF combining :angiotensin-converting enzyme inhibitor, beta blocker, mineralocorticoid receptor antagonists and sodium-glucose cotransporter 2 inhibitors. Coronary arteries were normal at angiography suggesting initially the diagnostic of myocarditis. Therefore, a cardiac magnetic resonance imaging was performed to confirm the latter, which showed an image consistent with a recent left ventricular subendocardial infarction, remarkably prominent in the left anterior descending artery territory and the absence of signs of myocarditis. The patient had no previous past medical history or other clinical features explaining this coronary event onset. Thus, the vaccine was potentially to be implicated in the pathophysiology of the event. Overall, complications associated with COVID-19 vaccines are extremely rare, and their benefit is well established. That''s why they continue to be recommended by public health experts despite of their rare side effects.     

Acute myocardial infarction: MR evaluation in 29 patients

This study evaluated the ability of MR to identify and characterize the region of myocardial infarction in humans. Twenty-nine patients, all with ECG and enzyme rises consistent with an acute myocardial infarction, were studied by MR 3-17 days from the onset of acute chest pain. Four patients were excluded because of inability to acquire adequate MR studies. For comparison, 20 normal subjects were studied who also had gated MR examinations. The site of infarction was visualized in 23 patients as an area of high signal intensity in relation to the normal myocardium, a contrast that increased on the second-echo image. The regions of abnormal signal intensity corresponded to the anatomic site of infarction as defined by the ECG changes. The mean T2 relaxation time of the infarcted myocardium (79 +/- 22 msec) was significantly prolonged in comparison with the mean T2 (43.9 +/- 9 msec) of normal myocardium (p less than .01). The mean percentage of contrast (intensity difference) between normal and infarcted myocardium was much greater on the second-echo images (65.6 +/- 34.0%) than the first-echo images (27.5 +/- 18.7%). In the normal subjects there was no difference in T2 between the anterolateral (40.3 +/- 5.7 msec) and septal (39.5 +/- 7.4 msec) regions, and percentages of contrast between these two regions of myocardium on the first-echo (9.1 +/- 7.4%) and second-echo (15.0 +/- 13.3%) images were similar. Thus, MR can be used to directly visualize acute infarcts. However, it has several pitfalls, including the necessity to differentiate signal from slowly flowing blood in the ventricle, from increased signal from a region of infarction and artifactual variation of signal intensity in the myocardium due to respiratory motion or residual cardiac motion.     

Acute myocardial infarction in a young woman: Unexpected findings of a coronary occlusion

In clinical and forensic practice, the cause of death is often attributed to acute myocardial infarction, among which the coronary atherosclerosis being the Captain of the Men of Death. However, other reasons such as coronary septic embolization with neutrophilic granulocyte myocarditis although rare, can also cause sudden unexpected death. This paper reports a case with this rare cause—a 21-year-old woman diagnosed with “acute gastroenteritis” who died 4 days later. A forensic autopsy revealed an inflammatory polypous embolic located at 1.0 cm from the left anterior descending branch (LAD) with serve neutrophilic granulocyte myocarditis, which resulted in embolic at the opening of the left main coronary artery, acute myocardial infarction and eventually leading to her death. Histopathological examination showed large amounts of neutrophilic granulocyte infiltration in the arterial layer forming the septic embolic and eventually resulting in coronary occlusion. To find the real cause of septic embolic, myocarditis, bacterial, fungal, protozoan and virus detection was performed through RT-PCR, with negative findings. Septic embolic leading coronary occlusion in left main coronary artery and LAD is rarely reported in forensic practice, we hope this report can pave the way on understanding this rare disease to make correct diagnosis in medical practice.     

急性心肌梗死合并肾梗死1例

临床资料 患者男,45岁.因“持续性胸闷,胸痛2d”于2015年5月17日入院,否认高血压、糖尿病、心脏病病史,有吸烟史30年,约20支/d,少量饮酒,曾有吸毒史.患者于3d前晚19时许无明显诱因突发胸骨下段压榨性疼痛,无放射痛,伴大汗淋漓、恶心、呕吐胃内容物、咳嗽咯痰,持续无缓解,遂来娄底市中心医院心血管内科就诊.     

Comparison between unstable angina pectoris and stable effort angina pectoris by using 123I-BMIPP and 201Tl myocardial SPECT

We performed BMIPP myocardial SPECT and Tl myocardial SPECT in patients with unstable angina (UAP) and stable effort angina (SAP), and compared the results for the two groups. Our subjects were 30 patients with the UAP and 25 patients with the SAP. The early and delayed images of the BMIPP were obtained with patients at rest. The early image of the Tl alone was obtained with patients at rest. We calculated severity score (SS) using the polar map based on SPECT short-axis image on the both myocardial SPECT. And, we calculated % uptake of the responsible coronary lesion and regional washout rate (WR) on myocardial SPECT with BMIPP. On coronary angiogram, no difference in % diameter stenosis was seen between the two groups. On myocardial SPECT with Tl, no difference in the SS was seen between the two groups. However, on myocardial SPECT with BMIPP, the SS was significantly higher score in the UAP group than in the SAP group. And, on myocardial SPECT with BMIPP, the % uptake and the WR were significant lower values in the UAP group than in the SAP group. Even if the two groups have almost the same level of myocardial perfusion disorder, the UAP group may have severer myocardial fatty-acid metabolic disorder than the SAP group, because the defects in BMIPP were significantly severer in the UAP group.     

Acute myocardial infarction demonstrated by multidetector CT scanning

A 55-year-old man was brought to the emergency room complaining of left-sided chest pain. His electrocardiogram was indeterminate, and a multidetector computed tomogram (MDCT) was performed to exclude aortic dissection. The patients aorta was normal, but an area of hypoperfusion was evident in the lateral ventricular myocardial wall. The ability to diagnose myocardial ischemia and infarcts on nongated MDCT is of particular clinical interest. As more imaging technology is devoted to imaging the heart, the greater expectations of radiologists ability to diagnose cardiac disease in the emergency room will become.