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C G de Araújo

Publications and source records attributed to C G de Araújo.

5 recordsLinked to original sources

[Criteria for electrocardiographic diagnosis of vagotonia. Is there a consensus in the opinion of specialists?].

PURPOSE: To identify the most important criteria for the ECG diagnosis of vagotonia in the opinion of cardiologists. METHODS: A written questionnaire was applied to 40 cardiologists attending the 9th Brazilian Congress of Cardiac Arrhythmias (S. José do Rio Preto, SP, 1992). The sample represented approximately 15% of all participants and was intentionally biased to include 70% of the invited speakers and free communications presenters, and to exclude non-medical professionals, aiming to enhance the validity of the answers. It was divided in two parts: the first, with spontaneous response, answered without knowledge of the following; and the second, where a list of ECG criteria obtained in the literature was presented to the respondent in a random order. In both parts, the specialists were requested to attribute an order of importance for each criterion. RESULTS: In the 1st part, 35 different criteria were cited, but only 3 were assigned by more than 25% of the sample: sinus bradycardia (95%), tall and peaked T waves (30%) and early repolarization (27.5%). In the 2nd part, the best classified criterion was sinus bradycardia, followed by J point elevation and ST segment elevation. CONCLUSION: Among cardiologists with a interest in electrocardiography and cardiac arrhythmias, apart of sinus bradycardia, there is no clear consensus concerning to the group of criteria to identify vagotonia in the standard 12-lead ECG. Further research is necessary to objectively validate the main criteria herein identified.

Arrhythmias, Cardiac↗

[Initial heart rate transient at dynamic exercise performed in apnea. Influence of the variation rate of previous lung volume].

PURPOSE: To study the influence of inspiratory flow on the heart rate (HR) responses during the four-second exercise test (4sET) as a method to estimate cardiac vagal activity. METHODS: Fifteen healthy subjects performed the 4sET under two experimental situations: a) with maximal individual inspiratory flow (MIF) and b) with a slow inspiratory flow adjusted to reach total lung capacity in 4s (SIF). Vagal activity was estimated from B/C ratio obtained in ECG tracings, where B is the last R-R interval before the onset of exercise and C is the shortest R-R interval during exertion. RESULTS: Similar inspiratory capacities were reached, with significantly different inspiratory flows [mean (se)] [MIF = 2.23 (0.28) 1.s-1 and SIF = 0.59 (0.06) 1.s-1; t = 6.69; p < 0.0001]; as a result, it was observed a greater B/C ratio in MIF [1.36 (0.05)] as compared to SIF [1.13 (0.04); t = 4.42; p = 0.0006]. The inspiratory flow influenced HR responses in the 4sET. The biphasic transient induced by inspiration, with a HR acceleration followed by a relative bradycardia, has not been completed before exercise in the 4sET with SIF. CONCLUSION: Lower values of B/C in the 4sET with SIF seemed to be due to overlapping effects of apnea and exertion on HR during cycling. On the other hand, when the inspiration was performed at MIF, the oscillatory effect of respiration upon HR was completed before the onset of exercise. Therefore, the tachycardia observed during the 4sET performed after individual maximal inspiratory flow represents the isolated effect of dynamic exercise.

Adolescent↗