Abstract |
In 55 patients with persistent sinus bradycardia who underwent an electrophysiologic study of sinus node, both in the basal state and after autonomic blockade ( propranolol, 0.2 mg/kg, and atropine, 0.04 mg/kg), an atropine test (0.02 mg/kg) was performed the following day. The 49 patients in whom sinus rate could be evaluated after atropine were subdivided into two groups--group I, 24 patients (age: 54 +/- 13 years) with normal intrinsic sinus automaticity (normal intrinsic heart rate and intrinsic corrected sinus node recovery time) and group II, 25 patients (age: 62 +/- 9 years) with abnormal intrinsic sinus automaticity. In group I, atropine increased sinus rate from 53.7 +/- 4 to 87.9 +/- 17 bpm (delta %: 65.5 +/- 33) and in group II from 51.6 +/- 5 to 73.9 +/- 14 bpm (delta %: 43.1 +/- 26). The discriminant threshold of sinus rate after atropine and its percent increase, obtained by discriminant analysis, was 80 bpm and +52%, respectively, with a misleading classification of 32% and 36%, respectively. The overall predictive accuracy of sinus rate after atropine was higher than the percent change in sinus rate (73% and 65%, respectively). These data evidence that the atropine test is not very helpful in discriminating between an organic and an autonomic involvement of sinus automaticity in patients with sinus bradycardia.
|
Authors | R Cappato, P Alboni, N Paparella, T Toselli, G C Candini, A M Tomasi |
Journal | American heart journal
(Am Heart J)
Vol. 114
Issue 6
Pg. 1384-8
(Dec 1987)
ISSN: 0002-8703 [Print] United States |
PMID | 3687691
(Publication Type: Journal Article)
|
Chemical References |
|
Topics |
- Adult
- Aged
- Arrhythmia, Sinus
(diagnosis, physiopathology)
- Atropine
- Autonomic Nerve Block
- Bradycardia
(diagnosis, physiopathology)
- Female
- Heart Function Tests
- Heart Rate
(drug effects)
- Humans
- Male
- Middle Aged
- Propranolol
(pharmacology)
- Sinoatrial Node
(drug effects, physiopathology)
|