Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0151744 (myocardial ischemia)
 31,282 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We devised a technique to record a greater number of leads (a 9-lead monitor) by connecting a lead-switching adaptor to a commercially available 3-channel Holter recorder (9-lead DCG). Anodes were attached from positions V1 to V6 (CM1 to CM6), and to high lateral (HL), low lateral (LL) and low back (LB). A cathode was attached to the manubrium of the sternum. The CM5 lead was continuously recorded on channel 1. The device is able to switch continuously every 20 sec among leads CM6, LB, HL and LL on channel 2, and among leads CM1, CM4, CM2, and CM3 on channel 3. Electrocardiograms were simultaneously recorded with both the 9-lead DCG and the conventional 12-lead ECG systems during treadmill testing in 67 patients with coronary artery disease. In addition, 6 patients with acute myocardial infarction were studied with the 9-DCG to test ST elevation. The sensitivity and specificity of leads CM2 to CM6, HL, LL, and LB in detecting ST depressions that occurred in each corresponding lead of the 12-lead ECG lead were very high (p < 0.0001). The LB lead in particular was noteworthy for its markedly high specificity (94%) and sensitivity (83%) in detecting ST depressions occurring in leads II and aVF. Our lead-switching technique is useful when an increase in the number of leads is required in the DCG method. The LB lead, an anode on the low back, may be specific to detect inferior myocardial ischemia.
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PMID:Nine-lead Holter monitoring using a lead-switching technique for the detection of ischemic ST changes. 147 47

The coronary vessels of 70 human hearts were visualized postmortem by injection of the coronary arteries with a X-ray opaque substance (for angiographic studies) or with a low viscosity resin (to obtain vascular casts). Analysis of the data suggests a new anatomical systematization of the vascularization of the myocardial tissue of human heart ventricles: it can be divided into four zones each having a different origin of the arterial vessels. These four components of the heart ventricles are the antero-septal (AS), postero-septal (PS), left-lateral (LL), and right-lateral (RL) zones. They correspond to the territories of the anterior interventricular branch of the left coronary artery (AS zone), of the posterior interventricular branch of the right coronary artery (PS zone), of the left circumflex artery (LL zone), and of the right coronary artery (RL zone) up to the origin of the posterior interventricular artery. This systematization of the arterial heart ventricles in zones offers a balanced division of the myocardial tissue, since each of the four zones occupied about one fourth of the total volume of the ventricles. In our samples, the most common distribution of segments in the wall of heart ventricles was the following: 16 segments in the AS zone, 11 segments in the PS zone, 5 segments in the LL zone, and 4 segments in the RL zone. The separation of four zones in the walls of heart ventricles, each of them made up of different segments, may be helpful in the understanding of the pathophysiology of myocardial ischemia, and also in the choice of surgical strategies to treat aneurisms of the heart ventricle wall.
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PMID:Anatomical basis for the separation of four cardiac zones in the walls of human heart ventricles. 772 89

We devised a nine-lead Holter monitor system with a lead-switching technique to record electrocardiograms from multiple sites in the anterior and the posterior or lateral chest. Leads CM1 to CM6, high lateral (HL), low lateral (LL), and low posterior chest (LB) were used. The sensitivity, specificity, and predictive accuracy of this system for identifying specific regions of myocardial ischemia and coronary artery disease were investigated in 130 patients with coronary artery disease. Anterolateral leads (CM4 to CM6, HL, and LL) showed high sensitivity for detecting anterior and lateral ischemia (69% to 100%) but low specificity (4% to 44%) compared with tomographic results. The specificity of these leads for identifying single-vessel disease was low (6% to 47%) although some leads showed high sensitivity (69% to 100%). In contrast, the LB lead exhibited high sensitivity and specificity for detecting inferior ischemia (70% and 95%, respectively) and right coronary artery (RCA) disease (74% and 93%, respectively). Consequently, ST depressions in the LB lead (anode) are specific for identifying inferior ischemia and RCA disease, whereas those in the anterior and lateral chest leads do not identify the ischemic region or the obstructed coronary artery.
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PMID:Evaluation of a nine-lead Holter monitor for identifying and localizing ischemia and coronary artery disease detected by quantitative thallium-201 tomography. 794 90

A 9-lead Holter monitoring apparatus was devised using a commercially-available 3-lead Holter recorder. The CM5 lead was monitored continuously on channel 1, and our apparatus was applied to channels 2 and 3. Channel 2 was switched serially to V1-like (CM1), V4-like (CM4), V2-like (CM2) and V3-like (CM3) leads every 20 sec. Channel 3 was switched serially to V6-like (CM6), low-back (LB), high lateral (HL) and low-lateral (LL) leads every 20 sec. The study subjects included 98 patients with coronary artery disease. Myocardial ischemia was evaluated by exercise thallium-201 (Tl-201) scintigrams. Functional maps of myocardial perfusion were made from Tl-201 myocardial SPECT studies, and the extent and severity scores were calculated from these maps. The CM5 lead had a high sensitivity for detecting anterior, inferior and lateral wall ischemia, however, its specificity was very low. In contrast, the LB lead had very high sensitivity and high specificity for detecting inferior ischemia (79%, 76%, respectively). The percent extent score and percent severity score determined by the bull's eye method were compared between patients with ST depression of 0.5-1.0 mm and those with that greater than 1.0 mm detected by the LB lead. Both the percent extent score and percent severity score in the latter group were significantly higher than those in the former group (p < 0.001, p < 0.01, respectively), suggesting that the degree of ST depression in the LB lead reflects the degree of myocardial ischemia. The HL and LL leads had high sensitivity and specificity for detecting lateral ischemia. It was concluded that the CM5 lead is necessary for screening global myocardial ischemia and that leads LB and HL (or LL) are mainly useful for detecting inferior and lateral ischemia.
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PMID:[A newly-devised nine-lead Holter system for diagnosing myocardial ischemia evaluated using Tl-201 exercise scintigraphy]. 816 32