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- Hedeer, Fredrik, et al.
(författare)
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To what extent are perfusion defects seen by myocardial perfusion SPECT in patients with left bundle branch block related to myocardial infarction, ECG characteristics, and myocardial wall motion?
- 2021
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Ingår i: Journal of Nuclear Cardiology. - : Springer Science and Business Media LLC. - 1071-3581 .- 1532-6551. ; 28:6, s. 2910-2922
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: We investigated if uptake pattern on myocardial perfusion SPECT (MPS) in patients with left bundle branch block (LBBB) is related to myocardial fibrosis, myocardial wall motion, and electrocardiography (ECG) characteristics. Methods: Twenty-three patients (9 women) with LBBB, examined with MPS and cardiac magnetic resonance (CMR), were included. Tracer uptake on MPS was classified by visual interpretation as typical LBBB pattern (Defect+, n = 13) or not (Defect−, n = 10) and quantitatively. CMR images were evaluated for wall thickness and for myocardial wall motion both by visual assessment and by regional myocardial radial strain from feature tracking, and for presence and location of myocardial fibrosis. ECGs were analyzed regarding QRS duration and the presence of strict criteria for LBBB. Results: Wall thickness was slightly lower in the septum compared to the lateral wall in Defect+ patients (5.6 ± 1.1 vs 6.0 ± 1.3 mm, P = 0.03) but not in Defect− patients (5.6 ± 1.0 vs 5.6 ± 0.9 mm, P = 0.84). Defect+ patients showed a larger proportion of dyskinetic segments in the septum and hyperkinetic segments in the lateral wall compared to Defect− patients (P = 0.006 and P = 0.004, respectively). Decreased myocardial radial strain was associated with decreased tracer uptake by MPS (R = 0.37, P < 0.001). Areas of fibrosis did not match areas with uptake defect on MPS. No differences in ECG variables were seen. Conclusion: The heterogeneous regional tracer uptake in some patients with LBBB is related to underlying regional myocardial dyskinesia, wall thickening, and wall thickness rather than stress-induced ischemia, myocardial fibrosis, or specific ECG characteristics.
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- van Deursen, Caroline J M, et al.
(författare)
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Vectorcardiographic QRS area as a novel predictor of response to cardiac resynchronization therapy.
- 2015
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Ingår i: Journal of electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 48:1, s. 45-52
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Tidskriftsartikel (refereegranskat)abstract
- QRS duration and left bundle branch block (LBBB) morphology are used to select patients for cardiac resynchronization therapy (CRT). We investigated whether the area of the QRS complex (QRSAREA) on the 3-dimensional vectorcardiogram (VCG) can improve patient selection.
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- van Deursen, Caroline J M, et al.
(författare)
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Vectorcardiography for Optimization of Stimulation Intervals in Cardiac Resynchronization Therapy.
- 2015
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Ingår i: Journal of cardiovascular translational research. - : Springer Science and Business Media LLC. - 1937-5395 .- 1937-5387. ; 8:2, s. 128-137
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Tidskriftsartikel (refereegranskat)abstract
- Current optimization of atrioventricular (AV) and interventricular (VV) intervals in cardiac resynchronization therapy (CRT) is time consuming and subject to noise. We aimed to prove the principle that the best hemodynamic effect of CRT is achieved by cancelation of opposing electrical forces, detectable from the QRS morphology in the 3D vectorcardiogram (VCG). Different degrees of left (LV) and right ventricular (RV) pre-excitation were induced, using variation in AV intervals during LV pacing in 20 patients with left bundle branch block (LBBB) and variation in VV intervals during biventricular pacing in 18 patients with complete AV block or atrial fibrillation. The smallest QRS vector area identified stimulation intervals with minimal systolic stretch (median difference [IQR] 20ms [-20, 20ms] and maximal hemodynamic response (10ms [-20, 40ms]). Reliability of VCG measurements was superior to hemodynamic measurements. This study proves the principle that VCG analysis may allow easy and reliable optimization of stimulation intervals in CRT patients.
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- Wecke, Liliane, et al.
(författare)
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Repolarization changes in patients with heart failure receiving cardiac resynchronization therapy-signs of cardiac memory
- 2011
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 44:5, s. 590-598
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Tidskriftsartikel (refereegranskat)abstract
- Background and Purpose Cardiac memory is known as T-wave inversions and other repolarization changes after a period of altered ventricular activation, previously mainly studied in structurally normal hearts. We investigated repolarization changes in failing hearts undergoing cardiac resynchronization therapy (CRT). Methods Electrocardiogram and vectorcardiogram were recorded before and 1 day and 2 weeks after initiation of CRT in 23 patients with heart failure and left bundle-branch block. Results After 1 day of CRT, the T vector during intrinsic conduction (left bundle-branch block) had rotated toward the direction of the paced QRS vector; T-vector size had increased with further increase after 2 weeks (T-vector amplitude, 889 ± 277 vs 651 ± 225 μV; T area, 169 ± 70 vs 102 ± 39 μVs; P < .01) accompanied by prolonged repolarization (T peak-to-end, 174 ± 34 vs 127 ± 16; QT interval corrected for heart rate, 541 ± 59 vs 493 ± 33 milliseconds; P < .01). Conclusions Repolarization changes are present in patients with heart failure, although less pronounced compared with after right ventricular pacing in structurally normal hearts.
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