| 1. |
- Billgren, T, et al.
(författare)
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Detailed definition and interobserver agreement for the electrocardiographic Sclarovsky-Birnbaum ischemia grading system
- 2002
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 35, s. 201-202
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Tidskriftsartikel (refereegranskat)abstract
- A generally implementable method for predicting salvageability on the presenting electrocardiogram (ECG) in patients with acute myocardial infarction (AMI) would be of great clinical importance. ECG-derived Grades of Ischemia (1) have been proven useful in predicting the extent and severity of left ventricular dysfunction after anterior MI, estimating short and long-term prognosis, final infarct size, and salvageability by reperfusion therapy (2).
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| 2. |
- Billgren, T, et al.
(författare)
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Refinement and interobserver agreement for the electrocardiographic Sclarovsky-Birnbaum Ischemia Grading System
- 2004
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 37:3, s. 149-156
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Tidskriftsartikel (refereegranskat)abstract
- Background: Electrocardiogram-derived grades of ischemia at the time of patient presentation with acute myocardial infarction have proved useful in predicting the salvageability by reperfusion therapy, final infarct size, severity of left ventricular dysfunction, and short- and long-term prognosis. Subjects and Methods: The Sclarovsky-Birnbaum Ischemia Grading System based on the relation between the acute appearances of the T wave, the ST segment, and the QRS complex was considered as a means of enhanced ECG analysis in this group of patients. The evaluation of a training population (n = 46) resulted in refinement of the published description of the Sclarovsky-Birnbaum Ischemia Grading System, and a test population (n = 50) was utilized for investigating the interobserver agreement among 5 observers in determining the grade of ischemia. Results: The agreement among the observers applying the "refined" Sclarovsky-Birnbaum Ischemia Grading System was 0.89. Complete agreement was found for the ECGs of 80% of the patients, and the most common reason for disagreement was the application of the terminal T-negativity criterion. Conclusions: The refined Sclarovsky-Birnbaum Ischemia Grading System can be performed manually with low interobserver variability. It has potential for support of the acute myocardial infarction triage decision as an electrocardiographic method for evaluating the level of ischemic protection at the time of either pre-hospital or emergency-department presentation.
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| 3. |
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| 4. |
- Kongstad Rasmussen, Ole, et al.
(författare)
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Global and local dispersion of ventricular repolarization: endocardial monophasic action potential mapping in swine and humans by using an electro-anatomical mapping system.
- 2002
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 35:2, s. 159-167
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Tidskriftsartikel (refereegranskat)abstract
- This article evaluates whether the global dispersion of ventricular repolarization (DVR) can be estimated from measurements between a few adjacent or remote sites. Monophasic action potentials (MAP) were recorded from 61 +/- 18 left (LV) or right ventricular (RV) sites in 10 pigs and 44 +/- 16 LV, or RV sites in 8 patients by using the CARTO mapping system. MAP duration (MAPd) and end-of-repolarization time were calculated at each site and 13 repolarization maps from pigs and 10 from patients were reconstructed. Global dispersions in MAPd and EOR over the LV or RV were compared with the adjacent DVR among 3 - 7 MAPs in areas > or = 0.7 and < or = 1 cm(2) and with the remote DVRs between 2 MAPs with the greatest activation time difference (remote DVR1) and between the apical and laterobasal LV or RV (remote DVR2). The adjacent dispersions in end-of-repolarization and MAPd were significantly smaller than the global ones, 13 +/- 3 and 12 +/- 3 ms vs. 44 +/- 9 and 42 +/- 12 ms in pigs and 13 +/- 7 and 14 +/- 8 ms vs. 72 +/- 24 and 66 +/- 22 ms in patients. The remote DVR1 (30 +/- 8 and 17 +/- 10 ms in pigs and 40 +/- 28 and 28 +/- 17 ms in patients) and remote DVR2 (16 +/- 7 and 11 +/- 10 ms in pigs and 35 +/- 24 and 21 +/- 21 ms in patients) were also significantly smaller than the global DVRs. In conclusion, global DVR is poorly estimated from MAP recordings from a few adjacent or remote sites, suggesting the importance of obtaining global information in evaluating DVR.
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| 5. |
- Li, Zhen, et al.
(författare)
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Dispersion of refractoriness in patients with paroxysmal atrial fibrillation: Evaluation with simultaneous endocardial recordings from both atria.
- 2002
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 35:3, s. 227-234
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Tidskriftsartikel (refereegranskat)abstract
- This article studies the role of dispersion of atrial refractoriness (DAR) in the genesis of atrial fibrillation (AF). A 20-polar Halo catheter or a 40-polar basket catheter was placed in the right atrium and a 10-polar catheter in the coronary sinus in 21 patients with paroxysmal AF. Bipolar electrograms during AF were recorded from 7 to 16 sites in both atria. As control, electrograms during AF induced by extra-stimulation or burst pacing were also recorded from 4 to 14 sites in both atria in 12 patients with supraventricular tachycardias but without history of AF. The local atrial fibrillation intervals (AFI) during a period of 10 s or 20 s were measured and the mean, median and the 5th, 10th and 15th percentile AFIs at each site were calculated as estimates of the local effective refractory period (AERP). The maximum dispersion and variance of the estimated AERP among the 7-16/4-14 sites were used as measures of the DAR. The maximum dispersion and variance of the 5th and 10th percentile AFIs were significantly greater in the AF group than those in the control group, which were mainly due to the shortening of the minimum 5th and 10th percentile AFIs. No significant differences in dispersion and variance of the mean and median AFIs were shown between the 2 groups. The dispersion and variance of atrial refractoriness during AF estimated from the measurement of short AFIs were significantly greater in patients with paroxysmal AF than in those without clinical AF. The increased dispersion of refractoriness in patients with AF was mainly due to the shortening of the minimum AFIs. These findings suggest the involvement of an increased dispersion of atrial refractoriness in the genesis of paroxysmal AF.
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| 6. |
- Liu, Shaowen, et al.
(författare)
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Gender and atrioventricular conduction properties of patients with symptomatic atrioventricular nodal reentrant tachycardia and Wolff-Parkinson-White syndrome
- 2001
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 34:4, s. 295-301
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to delineate the sex distribution and atrioventricular conduction properties in patients with manifest or concealed Wolff-Parkinson-White syndrome (WPW) and atrioventricular nodal reentrant tachycardia (AVNRT). The study comprised 328 patients with AVNRT, 347 with manifest, and 220 with concealed WPW who underwent radiofrequency ablation. A male preponderance was observed in patients with manifest WPW (69%), but not in those with concealed WPW (52%) and female preponderance in AVNRT patients (67%). The PR (166 +/- 25 ms) and AH (88 +/- 20 ms) intervals obtained 30 minutes after ablation in manifest WPW patients were significantly longer than in concealed WPW patients (149 +/- 20, 76 +/- 15 ms, P <.0001). The PR (146 +/- 20 ms) and AH intervals (75 +/- 15 ms) measured before ablation in AVNRT patients were shorter than those obtained before ablation in concealed WPW patients (154 +/- 21, 80 +/- 17 ms, P <.05) and after ablation in manifest WPW patients (P <.0001). The PR interval in AVNRT patients was also shorter than those measured during follow-up in concealed (153 +/- 21 ms, P <.05) and manifest WPW patients (165 +/- 23 ms, P <.0001). The ventriculoatrial block cycle length in AVNRT patients was significantly shorter than in manifest and concealed WPW patients. When age-matched patients were assigned to each group, significant differences in PR interval were observed between men and women (159 +/- 22 vs. 151 +/- 22 ms, P <.0001). Differences in sex distribution exist among patients with manifest and concealed WPW and AVNRT. The atrioventricular conduction properties required for the manifestation of pre-excitation and induction of AVNRT and gender differences in atrioventricular conduction may account for the differences in sex distribution.
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| 7. |
- Pahlm, Olle, et al.
(författare)
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Comparison of waveforms in conventional 12-lead ECGs and those derived from EASI leads in children
- 2003
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 36:1, s. 25-31
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Tidskriftsartikel (refereegranskat)abstract
- To investigate the possibility of simplifying electrocardiogram (ECG) recording in children, we compared waveforms in conventional 12-lead ECGs to those derived from EASI leads in 221 children of various ages. The conventional 12-lead ECGs and the ECGs using EASI electrode positions were collected simultaneously. We developed and determined the value of age-specific transformation coefficients for use in deriving 12-lead ECGs from the signals recorded at the EASI sites. We compared the results of using age-specific coefficients to the results of using adult coefficients and studied the "goodness-of-fit" between the conventional and the derived 12-lead ECGs. The age-specific coefficients performed slightly better than the adult coefficients, and good agreement was usually attained between the conventional 12-lead ECG and the EASI-derived 12-lead ECG. Our conclusion is that EASI leads in children have the same high levels of "goodness-of-fit" to replicate conventional 12-lead ECG waveforms, as reported earlier in adults.
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| 8. |
- Rautaharju, PM, et al.
(författare)
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Comparability of 12-lead ECGs derived from EASI leads with standard 12-lead ECGs in the classification of acute myocardial ischemia and old myocardial infarction
- 2002
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 35:4, part 2, s. 35-39
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Tidskriftsartikel (refereegranskat)abstract
- We compared 12-lead electrocardiograms (ECGs) derived with an improved transformation matrix from EASI leads and standard 12-lead ECGs in the detection of acute myocardial ischemia and old infarction (MI). For the ischemia test, we used ECGs of 40 patients recorded prior to and at peak inflation during percutaneous transluminal coronary angioplasty, and for old MI we used test ECGs of 382 non-MI subjects and of 472 patients with prior MI documented by enzyme findings. Two experienced ECG readers served as separate, independent standards for lead-set comparisons, and the Philips ECG analysis program also classified the ECGs. The results showed no significant differences between the two lead sets in the detection of acute inflation-induced ischemia or of old MI according to coding by the electrocardiographers or the computer program. No significant differences were found between the electrocardiographers and the lead sets for acute ischemia. Classification differences between the electrocardiographers were larger than those between the lead sets for acute and old MI and were significant for the latter (P <.001). A more detailed comparison of the lead sets suggested a possible need for modified old-MI criteria and optimization of ST classification thresholds for acute ischemic injury, specific for the EASI 12-lead ECG. We conclude that the EASI-derived 12-lead ECG deserves serious consideration as an alternative to the standard 12-lead ECG in emergency situations and for monitoring in acute-care setting.
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| 9. |
- Sgarbossa, EB, et al.
(författare)
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Twelve-lead electrocardiogram: The advantages of an orderly frontal lead display including lead -aVR
- 2004
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 37:3, s. 141-147
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Tidskriftsartikel (refereegranskat)abstract
- Background: It is possible that efforts in ECG review by both young experienced clinicians are currently discouraged-and risk to be completely dismissed-by the conventional (ie, disorderly) display of the frontal plane leads, with lead aVR at -150degrees. Methods: We reviewed studies on the usefulness of leads aVR and -aVR as well as on the history of the frontal leads in electrocardiography. Results: Lead aVR and particularly, lead -aVR, provide useful information when systematically analyzed. in addition, if lead -aVR is examined in its anatomically logical sequence, ie, aVL, 1, -aVR, 11, aVF, and 111, the frontal plane of the 12-lead ECG is more easily understood. This "panoramic" or "orderly" display is in common use in countries such as Sweden, but it is rarely seen in the United States. Conclusions: ECG interpretation would be enhanced by displaying the limb leads in an orderly arrangement that starts with lead aVL and ends with lead 111, and many ECG changes would be ideally displayed by a lead -aVR at 30degrees.
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| 10. |
- Svensbergh, A, et al.
(författare)
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ST-recovery loop of exercise-induced ST deviation in the identification of coronary artery disease: Which parameters should we measure?
- 2004
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 37:4, s. 275-283
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Tidskriftsartikel (refereegranskat)abstract
- This study aimed to characterize the ST-recovery loop and assess which range of heart rates (HRs) best discriminates between patients with and without significant coronary artery stenosis. Bicycle exercise tests were undertaken in 44 men and IS women with coronary artery disease (CAD) and in 59 controls (26 men, 33 women) in the same age range with no signs of CAD. The ST level and the ST-segment slope were continuously monitored, and changes from rest to peak exercise and to 4 min after exercise, respectively, were calculated. Plotting the ST level against HR gives the STHR loop, characterized by the normalized area (NA(alpha)) circumscribed by the ST level during and after exercise from alpha% to 100% of the HR range. Eight values of a between 20% and 90% were investigated, and chest and extremity leads were investigated separately. Optimal a was found to be less than or equal to70% in men and less than or equal to30% in women. Change in ST-segment slope was the only parameter that gave significant additional discriminating power in both men and women once the area had been taken into account. We conclude that NA(alpha) for extremity and chest leads have similar weights, and that a substantial part of the STHR loop should be taken into consideration, especially in women. NA(3O) was superior to end-exercise ST-depression and STHR loop orientation (as defined by the sign of NA(90) in both men and women, and to ST/HR index in men, in identifying CAD.
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