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- Bollmann, Andreas, et al.
(författare)
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Echocardiographic and electrocardiographic predictors for atrial fibrillation recurrence following cardioversion
- 2003
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Ingår i: Journal of Cardiovascular Electrophysiology. - : Wiley. - 1540-8167 .- 1045-3873. ; 14:s10, s. 162-165
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Identification of suitable candidates for cardioversion currently is not based on individual electrical and mechanical atrial remodeling. Therefore, this study analyzed the meaning of atrial fibrillatory rate obtained from the surface ECG (as a measure of electrical remodeling) and left atrial size (as measure of mechanical remodeling) for prediction of early atrial fibrillation (AF) recurrence following cardioversion. Methods and Results: Forty-four consecutive patients (26 men and 18 women, mean age 62 ± 11 years, no antiarrhythmic medication at baseline) with persistent AF were studied. Fibrillatory rate was obtained from high-gain, high-resolution surface ECG using digital signal processing (filtering, QRST subtraction, Fourier analysis) before electrical cardioversion. Univariate and multivariate regression analysis revealed larger systolic left atrial area (Beta = 0.176, P = 0.031) obtained by precardioversion echocardiogram from the apical four-chamber view and higher atrial fibrillatory rate (Beta = 0.029, P = 0.021) to be independent predictors for AF recurrence (n = 13). Stratification based on the regression equation (electromechanical index [EMI]= 0.176 systolic left atrial area + 0.029 fibrillatory rate − 17.674) allowed identification of groups at low, intermediate, or high risk. No patient with an EMI < −1.85 had early AF recurrence, as opposed to 78% with an EMI > −0.25. Intermediate results (40% recurrence rate) were obtained when the calculated EMI ranged between −1.85 and −0.25 (P < 0.001). Conclusion: Fibrillatory rate obtained from the surface ECG and systolic left atrial area obtained by echocardiography may predict early AF recurrence in patients with persistent AF. These parameters might be useful in identifying candidates with a high likelihood of remaining in sinus rhythm after cardioversion.
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| 2. |
- Bollmann, A, et al.
(författare)
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Frequency measures obtained from the surface electrocardiogram in atrial fibrillation research and clinical decision-making
- 2003
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Ingår i: Journal of Cardiovascular Electrophysiology. - : Wiley. - 1540-8167 .- 1045-3873. ; 14:s10, s. 154-161
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Tidskriftsartikel (refereegranskat)abstract
- Frequency Measures in AF. Introduction: Frequency analysis of fibrillation (FAF) and time-frequency analysis (TFA) were developed recently in order to quantify atrial electrical remodeling in atrial fibrillation (AF) from the surface ECG. This article describes the experience with these two different frequency analysis techniques in consecutive AF patients and discusses possible applications in AF research and clinical decision-making. Methods and Results: Baseline 2-minute, high-gain, high-resolution ECG recordings using three bipolar leads were obtained from 80 consecutive patients with AF lasting >24 hours. A power spectrum was obtained using Fourier analysis following spatiotemporal QRST cancellation. The dominant fibrillatory rate (in fibrillations per minute [fpm]) was derived (FAF). Stability of the instantaneous fibrillatory rate measured in overlapping 1-second segments was expressed as the segment proportion with consecutive rate differences <6 fpm (TFA). An adequate power spectrum that could be submitted for determination of fibrillatory rate was obtained in all patients. Dominant atrial rates ranged between 288 and 534 fpm and showed a high correlation (R = 0.878-0.911, P < 0.001) when assessed from the three different leads. The average instantaneous fibrillatory rate was inversely related with its stability (R = -0.417, P < 0.001). It was closely related with the dominant fibrillatory rate obtained from FAF (R = 0.948, P < 0.001). A literature review revealed that pharmacologic or electrical cardioversion and AF pace termination success rates were highly dependent on fibrillatory rate. Conclusion: Atrial fibrillatory rate and its variability can be reliable obtained from the surface ECG in AF patients. These parameters exhibit a significant interindividual variability allowing individual quantification of the atrial electrical remodeling process and might prove useful for predicting therapy efficacy.
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| 3. |
- Husser, D, et al.
(författare)
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Analysis of the surface electrocardiogram for monitoring and predicting antiarrhythmic drug effects in atrial fibrillation
- 2004
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Ingår i: Cardiovascular Drugs and Therapy. - : Springer Science and Business Media LLC. - 0920-3206 .- 1573-7241. ; 18:5, s. 377-386
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Forskningsöversikt (refereegranskat)abstract
- Specific antiarrhythmic therapy with class I and III drugs for atrial fibrillation (AF) conversion and prevention of its recurrence is frequently utilized in clinical practice. Besides being only moderate effective, the utilization of antiarrhythmic drugs may be associated with serious side effects. In the clinical setting it is difficult to directly evaluate the effects of antiarrhythmic drugs on the individual patient's atrial electrophysiology, thereby predicting their efficacy in restoring and maintaining sinus rhythm. Analysis of the surface electrocardiogram in terms of P-wave signal averaged ECG during sinus rhythm and spectral characterization of fibrillatory waves during AF for evaluation of atrial antiarrhythmic drug effects is a new field of investigation. Both techniques provide reproducible parameters for characterizing atrial electrical abnormalities and seem to contain prognostic information regarding antiarrhythmic drug efficacy. Further research is needed which elucidates the most challenging clinical questions in AF management whom to place on antiarrhythmic drug treatment and what antiarrhythmic drug to prescribe. Analysis of the surface ECG might have the potential to answer these questions.
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