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C Barnay

Publications and source records attributed to C Barnay.

At least 73 records · Page 4Linked to original sources

[Significance of pharmacodynamics tests in the study of sinus node function].

The evaluation of sinus function in man rests upon atrial stimulation techniques (rapid atrial stimulation, premature atrial stimulation); in a certain number of cases the results are inconclusive. There are various pharmaco-dynamic tests which can be used in such cases, the aim being to stimulate or depress the function of the sinus, or alternatively to modify the action of the extrinsic nerve supply. A study was carried out of sinus function in a series of 120 patients; pharmaco-dynamic tests were carried out using atropine in 43 cases, glucagon in 9 cases, isoproterinol in 9 cases, ajmaline in 9 cases, and piprofurol in 10 cases. The authors conclude from this study that it is worth adding the atropine test (which suppresses vagal tone), the glucagon test (which causes direct and limited stimulation of the sinus) and a test with an agent with a depressant action on the sinus coupled with a sympathetic-blocking action (such as piprofurol) to the conventional atrial stimulation tests.

Ajmaline↗

[Study of sinus node function. Preliminary results].

Direct exploration of the sinus node remains experimental. Indirect techniques have been put forward to assess the sinus function in man: high frequency atrial pacing; premature atrial pacing; pharmacodynamic tests using atropin and isoproterenol injection. 68 patients were so explored: in 10 of them were ECG signs suggestive of "sinus disease" or "atrium disease" (group I); 14 subjects had only a sinus bradycardia with a rate of 55/mn or below (group II); in 16 cases, the ECG tracing was normal, but there was the notion of paroxysmal tachycardia or various disturbances (group IIIa); finally, in 28 cases the ECG demonstrated atrio-ventricular or inter-ventricular conduction disturbances (group IIIb). The preliminary results reported here should be interpreted carefully; nevertheless, correlation of the data obtained by the various techniques used, seems to be able to allow a correct assessment of sinus automatism, and of sino-atrial conduction.

Adult↗

Effects of intravenous diltiazem on sinus node function and atrioventricular conduction in patients.

We studied the electrophysiologic effects of injectable diltiazem (dosage: bolus of 0.15 mg/kg, maintenance infusion of 0.3 mg/kg/h for 20 min) on sinus node function and atrioventricular function in 33 patients (22 men and 11 women, mean age 63.6 +/- 15.8 years). Seventeen patients had an electrophysiological exploration considered as normal, eight had sinus node dysfunction (corrected sinus recovery time greater than 525 ms), and eight had AV nodal block (PH greater than 160 ms and/or a Wenckebach point less than 125/min). Effects of the drug were assessed 20 min after the beginning of the infusion, which was continued until the end of examination. In normal subjects diltiazem lengthened corrected sinus node recovery time (305 +/- 115 ms leads to 451 +/- 283 ms) and slightly depressed AV nodal conduction (Wenckebach point: 163 +/- 23 leads to 147 +/- 25). In patients with sinus node dysfunction diltiazem provoked a bradycardia without significant changes in corrected sinus node recovery time or in estimated atrio-sino-atrial conduction time. In patients with AV nodal block diltiazem provoked a lowering of the Wenckebach point (137 +/- 47 leads to 122 +/- 38). There was no effect on hissian or infrahissian conduction, even when this was abnormal in the basal state. These data suggest that diltiazem must be utilized with caution in patients with sinus node dysfunction and AV nodal block.

Aged↗