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Screening for sinus node dysfunction by analysis of short-term sinus cycle variations on the surface electrocardiogram.

L Bergfeldt·M Rosenqvist·H Vallin·R Nordlander·H Aström
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Abstract

A new noninvasive screening method for diagnosing sinus node dysfunction (SND) was evaluated. Sinus cycle variations from 1-minute electrocardiograms (ECG) were described by two variables: the variation range around the mean cycle length (percentage) and the maximal change between any two consecutive cycles (milliseconds). SND was diagnosed when both variables were increased. Part 1: Validation of this method against Holter and sinus node recovery time assessment in 69 patients with proven or possible sick sinus syndrome (SSS). Part 2: Application of the method to 60 patients with clinically significant cardiovascular and pulmonary disorders (group 3), but without any pretest suspicion of SND. Part 1: Sinus cycle variations and sinus node recovery times were abnormal in similar proportions, 55% and 63%, respectively. The sensitivities in proven SSS were 72% and 71%, respectively. Sinus node function was concordantly classified in 80% of 64 patients undergoing both tests. When sinus cycle variations were abnormal the probability of a prolonged recovery time was 89%. Part 2: Asymptomatic SND was found in 12% of patients in group 3. Thus, analysis of short-term beat-to-beat variations in the surface ECG has a sensitivity of approximately 70% and a specificity of 100% for diagnosing SND.

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AdolescentAdultAgedAged, 80 and overArrhythmia, SinusConfidence IntervalsElectrocardiographyElectrocardiography, AmbulatoryFemaleHeart RateHumansMaleMiddle AgedPeriodicityProspective StudiesSensitivity and SpecificitySinoatrial NodeTime FactorsComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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L Bergfeldt, M Rosenqvist, H Vallin, R Nordlander, H Aström. 1995. Screening for sinus node dysfunction by analysis of short-term sinus cycle variations on the surface electrocardiogram.. https://doi.org/10.1016/0002-8703(95)90249-x

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