gms | German Medical Science

29. Wissenschaftlicher Kongress der Deutschen Hochdruckliga

Deutsche Hochdruckliga e. V. DHL ® - Deutsche Hypertonie Gesellschaft Deutsches Kompetenzzentrum Bluthochdruck

23. bis 25.11.2005, Berlin

Effect of the Average and the Variability of Heart Rate on Image Quality in 64-Slice CT Coronary Angiography

Einfluss der mittleren Herzfrequenz und deren Variabilität auf die Bildqualität bei der nicht-invasiven Koronarangiographie mittels 64-Zeilen CT

Meeting Abstract

  • S. Leschka - Universitätsspital Zürich, Institut für Diagnostische Radiologie (Zürich, CH)
  • H. Alkadhi - Universitätsspital Zürich, Institut für Diagnostische Radiologie (Zürich, CH)
  • L. Husmann - Universitätsspital Zürich, Institut für Diagnostische Radiologie (Zürich, CH)
  • A. Plass - Universitätsspital Zürich, Institut für Diagnostische Radiologie (Zürich, CH)
  • B. Marincek - Universitätsspital Zürich, Institut für Diagnostische Radiologie (Zürich, CH)
  • S. Wildermuth - Universitätsspital Zürich, Institut für Diagnostische Radiologie (Zürich, CH)

Hypertonie 2005. 29. Wissenschaftlicher Kongress der Deutschen Hochdruckliga. Berlin, 23.-25.11.2005. Düsseldorf, Köln: German Medical Science; 2006. Doc05hochP117

Die elektronische Version dieses Artikels ist vollständig und ist verfügbar unter: http://www.egms.de/de/meetings/hoch2005/05hoch117.shtml

Veröffentlicht: 8. August 2006

© 2006 Leschka et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielf&aauml;ltigt, verbreitet und &oauml;ffentlich zug&aauml;nglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

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Purpose: To evaluate the effect of the average and variability of heart rate on the image quality with 64-slice MDCT coronary angiography.

Materials and Methods: 125 patients (45 women, 80 men; mean age 59.9 ± 12.9 years) underwent 64-slice coronary CT angiography. MDCT data sets of the heart were reconstructed in 5% steps from 20 to 80% of the R-R interval. The ECG was digitally recorded and the variability of heart rate during scan was identified by calculating the standard deviation of the average heart rate for each patient. Two observers rated the image quality from 1 (no motion artifacts) to 5 (unassessable) for each coronary segment with a diameter of more than 1.5 mm. Image quality was correlated to the average heart rate and the heart rate variability during MDCT scan.

Results: Diagnostic image quality (score £ 3) was present in more than 99% of all coronary segments (1860/1875) when using the best reconstruction interval. The average heart rate was 63.3 ± 13.1 beats per minute (range 38 - 102) and the heart rate variability was 3.2 ± 2.1 (range 0.5 - 9.7). Overall image quality (mean 1.60 ± 0.59) did not significantly correlate with average heart rate (r = 0.25; p = ns), but significantly correlated with variability of heart rate during scan (r = 0.75; p < 0.05). Seventy-four patients had b blockers as part of their baseline medication. In these patients, heart rate was significantly more regular during scan compared with patients without b blocker, and overall image quality was significantly improved (p < 0.05). At heart rate < 75 bpm best image quality was mostly achieved in diastole, while in higher heart rate the reconstruction time point for best image quality shifted to systole.

Conclusions: In contrast to the average heart rate, reducing variations of the heart rate during scan by b blockers significantly improves image quality of coronary CT angiography with 64-slice CT.