| 1. |
- Pahlm, Ulrika, et al.
(författare)
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The 24-lead ECG display for enhanced recognition of STEMI-equivalent patterns in the 12-lead ECG.
- 2014
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 47:4, s. 425-429
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Forskningsöversikt (refereegranskat)abstract
- In a patient with chest pain and suspected acute coronary syndrome, the electrocardiogram (ECG) is the only readily available diagnostic tool. It is important to maximize its usefulness to detect acute myocardial ischemia that may evolve to myocardial infarction unless the patient is treated expediently with reperfusion therapy. Since diagnostic guidelines have usually included only ST-elevation myocardial infarction (STEMI) as the entity that should be diagnosed and treated urgently, a patient with coronary occlusion represented on ECG as ST depression is likely not to be considered a candidate for receiving immediate coronary angiography and coronary intervention. ECG criteria for STEMI detection require that ST elevation meet predetermined millivolt thresholds and appear in at least two spatially contiguous ECG leads. The typical ECG reader recognizes only three contiguous pairs: aVL and I; II and aVF; aVF and III. However, viewing the "orderly sequenced" 12-lead ECG display, two more contiguous pairs become obvious in the frontal plane: +I and -aVR; -aVR and +II. The 24-lead ECG is a display of the standard 12-lead ECG as both the classical positive leads and their negative (inverted) counterparts. Leads +V1, +V2, +V3, +V4, +V5, and +V6 and their inverted counterparts are used to generate a "clock-face display" for the transverse plane. Similarly, +aVL, +I, -aVR, +II, +aVF, +III in the frontal plane and their inverted counterparts are used to generate a clock-face display for the frontal plane. Optimum results, 78% sensitivity and 93% specificity, were obtained using the following 19 ECG leads: frontal plane: +aVR, -III, +aVL, +I, -aVR, +II, +aVF, +III, -aVL; transverse plane: +V1, +V2, +V3, +V4, +V5, +V6, -V1, -V2, -V3.
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| 2. |
- Perron, Annick, et al.
(författare)
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Maximal increase in sensitivity with minimal loss of specificity for diagnosis of acute coronary occlusion achieved by sequentially adding leads from the 24-lead electrocardiogram to the orderly sequenced 12-lead electrocardiogram
- 2007
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 40:6, s. 463-469
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: This study investigates whether sequential addition of inverted, (negative) leads from the 24-lead electrocardiogram (ECG) to the orderly sequenced 12-lead ECG would identify a number of leads with which the sensitivity for diagnosis of acute transmural ischemia is significantly increased with minimal loss of specificity. Background: Acute transmural ischemia due to thrombotic coronary occlusion typically progresses to infarction. Its recognition is based on currently accepted ST-elevation myocardial infarction (STEMI) criteria with suboptimal sensitivity, which could be potentially increased by consideration of the principle that each of the 12 ECG leads can be inverted to provide an additional lead with the opposite (180 degrees) orientation, generating a 24-lead ECG. Methods: The study population included 162 patients who underwent prolonged coronary occlusion during elective percutaneoas transluminal coronary angioplasty. Balloon occlusion was performed in the left anterior descending coronary artery (51 patients), in the right coronary artery (67 patients), or in the left circumflex coronary artery (44 patients). To be classified as indicative of the epicardial injury current of acute ischemia, the ECGs had to fulfill either the criteria of a consensus document from the American College of Cardiology or the European Society of Cardiology or thresholds for the inverted leads based on a population study from Scotland. Results: The addition of -V1, -V2, -V3, -aVL, -I, aVR, and -III increased sensitivity from 61% to 78% (P <= .01) and decreased specificity from 96% to 93% (P = .06). Conclusions: Addition of 7 leads from the 24-lead ECG, thus creating a 19-lead ECG, was found optimal for attaining high sensitivity while retaining high specificity when compared with the performance of the standard 12-lead ECG. (C) 2007 Elsevier Inc. All rights reserved.
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| 3. |
- Wagner, Galen S, et al.
(författare)
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Use of the 24-lead "standard" electrocardiogram to identify the site of acute coronary occlusion
- 2008
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 41:3, s. 238-244
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Tidskriftsartikel (refereegranskat)abstract
- This review presents the added value for diagnosis of acute ischemia/infarction of considering ST elevation in the 12 inverted leads (-I, -II, -II, -aVR, etc) of the standard electrocardiogram in addition to ST elevation in 12 positive leads. A small number of studies have been published showing substantial increases in sensitivity at the "cost of' slight decreases in specificity. One recent study indicated that only 7 of the inverted leads should be considered, yielding a "19-lead electrocardiogram" encompassing the following leads (presented here in the logical secquences): -III, aVL, I, -aVR, II, aVF, III, -aVL, -I, aVR; and V1, V2, V3, V4, V5, V6, -V1, -V2, -V3. Studies have to be performed to establish the thresholds that should be applied to these leads for achievement of sensitivity/specificity.
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| 4. |
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| 5. |
- Almer, Jakob, et al.
(författare)
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Ischemic QRS prolongation as a biomarker of severe myocardial ischemia.
- 2016
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 49:2, s. 139-147
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Tidskriftsartikel (refereegranskat)abstract
- Previous studies have shown that QRS prolongation is a sign of depressed collateral flow and increased rate of myocardial cell death during coronary occlusion. The aims of this study were to evaluate ischemic QRS prolongation as a biomarker of severe ischemia by establishing the relationship between prolongation and collateral flow experimentally in a dog model, and test if the same pattern of ischemic QRS prolongation occurs in man.
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| 6. |
- Elmberg, Viktor, et al.
(författare)
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A 12-lead ECG-method for quantifying ischemia-induced QRS prolongation to estimate the severity of the acute myocardial event.
- 2016
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 49:3, s. 272-277
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Tidskriftsartikel (refereegranskat)abstract
- Studies have shown terminal QRS distortion and resultant QRS prolongation during ischemia to be a sign of low cardiac protection and thus a faster rate of myocardial cell death. A recent study introduced a single lead method to quantify the severity of ischemia by estimating QRS prolongation. This paper introduces a 12-lead method that, in contrast to the previous method, does not require access to a prior ECG.
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| 7. |
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| 8. |
- Engblom, Henrik, et al.
(författare)
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Rapid Initial Reduction of Hyperenhanced Myocardium After Reperfused First Myocardial Infarction Suggests Recovery of the Peri-Infarction Zone One-Year Follow-Up by MRI
- 2009
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Ingår i: Circulation Cardiovascular Imaging. - 1942-0080. ; 2:1, s. 47-55
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Tidskriftsartikel (refereegranskat)abstract
- Background-The time course and magnitude of infarct involution, functional recovery, and normalization of infarct-related electrocardiographic (ECG) changes after acute myocardial infarction (MI) are not completely known in humans. We sought to explore these processes early after MI and during infarct-healing using cardiac MRI. Methods and Results-Twenty-two patients with reperfused first-time MI were examined by MRI and ECG at 1, 7, 42. 182, and 365 days after infarction. Global left ventricular function and regional wall thickening were assessed by cine MRI, and injured myocardium was depicted by delayed contrast-enhanced MRI. Infarct size by ECG was estimated by QRS scoring. The reduction of hyperenhanced myocardium occurred predominantly during the first week after infarction (64% of the 1-year reduction). Furthermore, during the first week the amount of nonhyperenhanced myocardium increased significantly (P<0.001,), although the left ventricular mass remained unchanged. Left ventricular ejection fraction increased gradually, whereas the greater the regional transmural extent of hyperenhancement at day 1, the later the recovery of regional wall thickening. Regional wall thickening decreased progressively with increasing initial transmural extent of hyperenhancement (P-trend<0.0001). The time course and magnitude of decrease in QRS score corresponded with the reduction of hyperenhanced myocardium. Conclusions-The early reduction of hyperenhanced myocardium May reflect recovery of hyperenhanced, reversibly injured myocardium), which must be considered when predicting functional recovery from delayed contrast-enhanced MRI findings early after infarction. Also, the time course and magnitude for reduction of hyperenhanced myocardium were associated with normalization of infarct-related ECG changes. (Circ Cardiovasc Imaging. 2009;2:47-55.)
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