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S Davidovitch

Publications and source records attributed to S Davidovitch.

9 recordsLinked to original sources
PubMed1998

Factors associated with the time of presentation of acute stroke patients in an Israeli community hospital.

Recently it has been shown that effective treatment for acute stroke must be initiated within 3-6 h from onset. In order to determine whether this is feasible and the reasons for delayed presentation, a prospective study was conducted in a community hospital in Israel. Of the 216 patients enrolled, 18% arrived at the hospital within 90 min of stroke onset and 54% presented within 6 h. Important factors associated with early presentation included major stroke (as compared to mild stroke) and time of day of onset (afternoon as compared with nighttime). Further efforts must be made to shorten the delay in hospital arrival of acute stroke patients.

Aged↗
PubMed1992

Propranolol in the prophylaxis of migraine--evaluation by spectral analysis of beat-to-beat heart rate fluctuations.

Migraine patients seem to suffer from a continuous autonomic imbalance. Sympathetic instability, expressed by enhanced low frequency fluctuations, which exists during the headache free intervals, was observed in our previous study by spectral analysis of heart rate (HR) fluctuations. Propranolol--a beta adrenoceptor antagonist, is widely used in migraine prophylaxis. In order to specify and quantitate propranolol efficacy in migraine, spectral analysis of heart rate fluctuations was performed on 10 migraine patients before and during the treatment with propranolol. They were compared to 10 healthy control patients and 6 migraine patients who were treated for several months with propranolol and then discontinued the medication. The analysis was carried out on a 24h Holter ECG recording, which was performed for each subject during a headache free interval. Short 256 sec subtraces, taken every 30 min from the 24h ECG signal, were submitted to A/D conversion, R wave detection and computation of heart rate power spectrum. Propranolol achieved a marked effect, when comparing the power spectra of HR fluctuations in treated versus untreated migraine patients. A strong reduction (to normal level) in the low frequency HR fluctuations in the range below 0.1 Hz., was apparent in patients treated with propranolol. Subjects who had received propranolol in the past and discontinued the drug, displayed a carry-over effect of reduced fluctuations even 2-3 months after its discontinuation. It seems that the propranolol efficacy in migraine is associated with the mechanism of stabilizing the fluctuations within the frequency band related to sympathetic activity, hereby moderating the vascular instability in migraine.

Adult↗
PubMed1988

Isolated phasic discharges in anterior tibial muscle: a stable feature of paradoxical sleep.

Phasic muscle discharges known currently as "fasciculations" are more frequently encountered in the limb skeletal muscles and predominate in the lower limbs when compared with the upper limbs. Of the lower limbs, the most active during paradoxical sleep (PS) is the anterior tibial muscle. When quantifying phasic discharges of the eyes versus a lower limb muscle during PS, the former are 14 times more frequent than the latter. During PS there is a sporadic and nonsignificant decrease in the tonus of the antigravitational extensor muscles. Isolated phasic discharges in anterior tibial muscles are a stable feature of PS.

Adult↗
PubMedDate not supplied

The effect of verapamil calcium antagonist on autonomic imbalance in migraine: evaluation by spectral analysis of beat-to-beat heart rate fluctuations.

Abnormalities in autonomic control have been documented in migraine even during the headache-free interval. It has long been recognized that spectral analysis of heart rate (HR) fluctuations can reflect the autonomic function, especially the sympathetic to parasympathetic balance. This technique is the basis for a quantitative approach to the investigation of migraine applied in the present study. A 24-hour Holter ECG recording was performed for each subject in a group of five migraine patients during the interheadache period. In addition, shorter 5-minute-long recordings of blood flow (BF) and blood pressure (BP) were made in these patients in both supine and standing positions. Short, 256-second subtraces were taken every 30 minutes along the 24-hour ECG signal and were submitted, as well as the BF and BP traces, to A/D conversion and computation of the power spectrum of fluctuations in HR, BF, and BP. Spectral analysis of fluctuations in these hemodynamic parameters was performed in the migraine patients before and during the treatment with verapamil and compared to that of a healthy control group. This procedure enabled us to assess the autonomic function, the sympathetic vs parasympathetic balance, and their response to a change in position, before and during calcium blockade. A characteristic autonomic abnormality is revealed in the group of untreated migraine patients in supine position: enhanced low frequency (LF) fluctuations reflecting increased sympathetic sensitivity during the inter-headache phase. An exaggerated sympathetic response is measured in the migraine patients during the transition from supine to standing position with a concomitant nonsignificant decrease in parasympathetic response.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗