PubMed Health⌕ Search

Biomedical subjects

K Wylie

Publications and source records attributed to K Wylie.

5 recordsLinked to original sources
PubMed1996

Pacing-induced chronic atrial fibrillation impairs sinus node function in dogs. Electrophysiological remodeling.

BACKGROUND: We assessed the effects of pacing-induced chronic atrial fibrillation (AF) on sinus node function, intra-atrial conduction, and atrial refractoriness. METHODS AND RESULTS: In 15 mongrel dogs (20 to 30 kg), AV nodal block was produced by radiofrequency catheter ablation, and a ventricular-inhibited (VVI) pacemaker (Minix 8330, Medtronic) was implanted and programmed to pace at 80 pulses per minute. In 11 of these dogs, right atrial endocardial pacing leads were connected to a pulse generator (Itrel 7432, Medtronic) and set at a rate of 20 Hz to induce AF. Corrected sinus node recovery time, P-wave duration, 24-hour Holter ECG to assess AF duration, maximal heart rate in response to isoproterenol (10 micrograms/min), intrinsic heart rate after administration of atropine (0.04 mg/kg) and propranolol (0.1 mg/kg), and atrial effective refractory periods (ERPs) were obtained at baseline (EPS-1) and after 2 to 6 weeks (EPS-2) of VVI pacing alone (n = 4) or VVI pacing and rapid atrial pacing (n = 11). At EPS-2, corrected sinus node recovery time and P-wave duration were prolonged, maximal heart rate and intrinsic heart rate were decreased, atrial ERPs were shortened, and the duration of AF was increased significantly compared with EPS-1. These changes partially reversed toward baseline 1 week after conversion to sinus rhythm. Sinus node function and AF inducibility observed in the control dogs that underwent ventricular pacing alone (n = 4) did not change. CONCLUSIONS: Pacing-induced chronic AF induces sinus node dysfunction, prolongs intra-atrial conduction time, shortens atrial refractoriness, and perpetuates AF, changes that reverse gradually after termination of AF.

Animals↗
PubMed1996

Pilot mental health assessment and diversion scheme for an English Metropolitan Petty Sessional Division.

A three-month pilot mental health assessment and diversion scheme was carried out at one of the busiest magistrates' courts outside London. In terms of demographic characteristics the sample of prisoners seen in this study was similar to those seen in diversion schemes in London and Manchester. Although 77 per cent of prisoners were found to be suffering from a psychiatric disorder, almost half were suffering from alcohol or drug dependence or misuse and the number with psychotic illnesses was small compared with the London sample. These differences may be partly due to the earlier diversion of acutely mentally ill prisoners from police custody into the health care system in Leeds. The low rate of psychiatric admission from the pilot scheme largely reflected these differences although in the cases of four patients admission was recommended by the assessing psychiatrist but not effected because of the lack of regional secure beds. Other problems identified by those involved in the scheme were the need for the provision of bail hostels specializing in the care of those with psychiatric difficulties and the need for the involvement of community psychiatric nurses within the assessment and diversion scheme.

Adolescent↗