Biomedical subjects

R Calfee

Publications and source records attributed to R Calfee.

3 recordsLinked to original sources

PubMed1986

New developments for upper rate response in DDD pacing.

Although widely accepted as an effective method of dealing with rapid atrial rates in a DDD pacemaker, Wenckebach-type and multiblock-type upper rate behaviors may exacerbate pacemaker-mediated tachycardia through AV dissociation. In addition, pathologic atrial rates (e.g., atrial fibrillation, atrial flutter, automatic atrial tachycardia, etc.) frequently result in ventricular pacing at inappropriately high rates. New, more sophisticated algorithms available in today's microprocessor-based DDD pacing systems provide the capability to discriminate successfully a normal atrial rate response to exercise from a pathologic atrial rate. These and other improved capabilities allow the clinician to provide safe rate-responsive pacing to patients in whom rate-responsive pacing was previously contraindicated.

Electrocardiography↗

PubMed1981

Multiprogrammable pacemakers.

Since 1962 it has been possible to change, by noninvasive means, the functions of implanted pacemakers. This study reports a 3-year multicentre experience, in 164 patients, with a multiprogrammable pacemaker that offers a wide range of choices within five variables: mode, rate, pulse width, sensitivity and telemetry (over 3000 combinations). In a selected series 83% of implanted pacemakers were programmed for medical indications and 100% for multiparameter follow-up studies. The advantage and disadvantages of three are compared. There is little doubt that multiprogrammable pacemakers can reduce the frequency of reoperation in any large series.

Arrhythmias, Cardiac↗

PubMed1977

The relation of auditory, visual, and auditory-visual matching to reading performance of Israeli children.

Six same-different matching tests, both verbal and nonverbal, in three modalities, along with a set of reading tests, were administered to 120 Israeli children in second, third, and fourth grade. The main effect of all S variables, except sex (grade, socioeconomic level, and ability) were significant, as were the test factors of modality (visual, auditory, cross-modal) and form (verbal-nonverbal), but interactions between S and test factors were small. Multiple regression analysis revealed that overall matching test scores accounted for 35% of the variance in reading scores, although the additional contribution of specific subtests was negligible. Performance on the visual-visual tests was virtually perfect. Auditory-auditory matches were more difficult than auditory-visual matches with nonverbal stimuli, while the reverse was true with verbal stimuli.

Auditory Perception↗