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F Arribas

Publications and source records attributed to F Arribas.

42 records · Page 3Linked to original sources

Fragmented electrograms and continuous electrical activity in atrial flutter.

Multiple endocardial bipolar electrograms were recorded in 13 patients with atrial flutter (AF) to locate areas of fragmented electrical activity. Stable fragmentation patterns were found in each case, covering between 36% and 100% of the flutter cycle. Double or triple spike patterns were common. The direction of atrial activation was approximately defined in 11 patients, and in all of them at least part of the areas showing fragmentation was included in the circuit. In 1 patient an area of continuous electrical activity was found. AF circuits appeared to be included in the right atrium in 12 patients and in the left atrium in 1 patient. During atrial stimulation changes in fragmented electrograms coincided with changes in AF pattern before its interruption, while restoration of stable AF after stimulation was accompanied by reappearance of previous stable fragmented electrograms. In 6 patients electrograms were recorded after sinus rhythm was reestablished, and all showed marked decreases or disappearance of fragmentation. It is concluded that fragmented electrograms are often found in AF and may be related to abnormal local conduction in relation to the reentrant activation circuits.

Adult↗

Effects of intravenous ajmaline on atrial excitability and conduction in man.

Slow conduction of early extrastimuli and short refractory periods are some of the factors underlying atrial fibrillation in man. In order to study the effect of ajmaline, a class I antiarrhythmic agent, on these variables, we have performed electrophysiologic studies in 13 patients with and without atrial arrhythmias, before and after the intravenous administration of 1 mg kg-1 of ajmaline chlorhydrate. During paced rhythm with a 600 ms cycle length, extrastimuli were applied to the right atrial appendage, and conduction to the low septal right atrium and the coronary sinus were measured. Ajmaline prolonged P wave duration from 111 +/- 15 to 140 +/- 24 ms (P less than 0.001), conduction of baseline stimuli to low septal right atrium from 69 +/- 14 to 95 +/- 21 ms (P less than 0.001) and to coronary sinus from 127 +/- 18 to 165 +/- 29 ms (P less than 0.001). Atrial effective refractory period increased from 207 +/- 23 to 255 +/- 27 ms (P less than 0.001). Maximum conduction delay of early extrastimuli decreased at the low septal right atrium from 43 +/- 22 to 29 +/- 16 ms (P less than 0.25) and at the coronary sinus from 47 +/- 22 to 21 +/- 14 ms (P less than 0.001). These results show interesting electrophysiologic effects of ajmaline on atrial tissue, with reversion of some of the abnormalities underlying atrial fibrillation, and suggest an antiarrhythmic effect.

Ajmaline↗

[Incidence of inflammatory bowel disease in Aragon: outcome of a prospective population-based study].

OBJECTIVE: To identify every new case of ulcerative colitis (UC) (including ulcerative proctitis), Crohn's disease (CD) and indeterminate colitis (IC) in Aragon, in Spain (population: 1,189,000, area: 47,719 km2) and to compare the incidence in this region with that in the rest of Spain and Europe. PATIENTS AND METHODS: We designed a prospective, population-based study based on inception cohorts. During a 3-year predetermined period (1st February 1992-31st January 1995) we identified every new case of inflammatory bowel disease in Aragon by checking the records in all the hospitals, outpatient clinics and private practices in this region. RESULTS: The overall adjusted incidence rate per 100,000 inhabitants/year was 7.2 for UC (a figure lower than the average for Europe) and 3.9 for Crohn's disease (a rate similar to that of Southern Europe). These rates are much higher than those previously described in Spanish studies, probably due to the design and methods used as well as to a real increase in the incidence of CD in Spain. The age and sex pattern was similar to those other studies. CONCLUSIONS: The incidence rates for inflammatory bowel disease in Aragon are higher than those previously described, the incidence of UC being inferior to that of Europe. Nevertheless, the incidence of CD is similar the average for southern Europe, which suggests that there has been a recent increase in the incidence of this disease in Aragon.

Adolescent↗