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Distribution of mean cycle length in cavo-tricuspid isthmus dependent atrial flutter

S Havránek1, J Simek, P Sťovíček

  • 1Second Department of Medicine - Department of Cardiovascular Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic. stepan.havranek@lf1.cuni.cz

Physiological Research
|December 23, 2011
PubMed

Insights

This study reveals cavo-tricuspid isthmus (CTI)-dependent atrial flutter (AFL) cycle lengths are not normally distributed. Short cycle lengths (<200 ms) are uncommon but do not exclude CTI-dependent AFL, particularly in younger patients.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Medical Research

Background:

  • Atrial flutter (AFL) cycle length (CL) is a key characteristic, yet large studies on cavo-tricuspid isthmus (CTI)-dependent AFL mean CL are lacking.
  • Understanding CL distribution is crucial for diagnosing and managing CTI-dependent AFL.

Purpose of the Study:

  • To describe the mean cycle length distribution in patients with electrophysiologically confirmed CTI-dependent AFL.
  • To identify factors associated with variations in AFL cycle length.

Main Methods:

  • Retrospective analysis of digital recordings from 121 patients undergoing radiofrequency ablation for persistent CTI-dependent AFL.
  • Statistical analysis including Shapiro Wilk test for normality and multivariate regression to identify associated factors.

Main Results:

  • The distribution of AFL cycle length was not normal (p<0.001), with a median of 240 ms (IQR 222-258 ms).
  • AFL cycle lengths <200 ms were observed in 4.1% of cases.
  • Age, antiarrhythmic drug treatment, and prior cardiac surgery were independently associated with longer AFL CL.

Conclusions:

  • The cycle length distribution of CTI-dependent atrial flutter is non-normal.
  • Short cycle lengths (<200 ms) are infrequent but do not rule out CTI-dependent AFL.
  • Age, specific antiarrhythmic drugs, and cardiac surgery history influence AFL cycle length.

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