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R Nitzsche

Publications and source records attributed to R Nitzsche.

8 recordsLinked to original sources
PubMed1997

Preliminary clinical experience with the first dual chamber pacemaker defibrillator.

The lack of specificity of VT detection is a significant shortcoming of current ICDs. In a French multicenter study, 18 patients underwent implantation of the Defender 9001 (ELA Medical), an ICD utilizing dual chamber pacing and arrhythmia detection. Over a mean follow-up period of 7.1 +/- 4.5 months, 176 tachycardia episodes recorded in the device memory were analyzed, and physician diagnosis was compared with that by the device. All 122 VT/VF episodes were correctly diagnosed, as were 51 of 53 supraventricular tachyarrhythmias. Two episodes of AF with rapid regular ventricular rates were treated as VT, and a third episode, treated as VT, could not be diagnosed with certainty. A dual chamber pacemaker defibrillator offers improved diagnostic specificity without loss of sensitivity, in addition to the hemodynamic benefit of dual chamber pacing.

Adolescent↗
PubMed1997

Value of automatic processing and reliability of stored data in an implanted pacemaker: initial results in 59 patients.

Stored data in implantable pacemakers have rarely been used as a diagnostic tool because of the complexity. Our group has developed software called AIDA, providing an automatic interpretation of data stored in memories of the Chorus (ELA medical) pacemaker. We compared the results of AIDA analysis to surface ECG Holter interpretation in 59 patients (age 75 +/- 9 years). In 33 cases, neither AIDA nor the Holter found any anomaly. Eleven patients demonstrated episodes of supraventricular tachycardia (SVT), confirmed by AIDA in ten patients; AIDA failure was due to nonsustained episodes of SVT not inducing mode switch. Loss of atrial sensing, pacemaker-mediated tachycardia, and ventricular extrasystoles were detected by AIDA in ten patients. Traditional Holter missed three cases. This initial study confirms that stored pacemaker data, automatically interpreted can provide reliable information over a 24-hour period.

Aged↗
PubMed1994

Electrophoretic mobility profiles: new aspects of characterization and discrimination of biological surfaces.

An advanced method of measuring and analyzing electrophoretic mobility profiles (electrophoretic fingerprints) was developed and for the first time applied to the cell surface. Dissociation constants calculated from a suitable mathematical model describe dissociation and, in part, adsorption processes on the surface and can thus be used for the characterization of complex processes on biological surfaces and the evaluation of small differences between cell surfaces.

Adsorption↗
PubMed1992

Atrial natriuretic factor release during exercise in patients successively paced in DDD and rate matched ventricular pacing.

Dual chamber pacemakers were implanted in nine patients with permanent second or third degree AV block (eight had complete retrograde block). Two identical exercise tests were performed after at least 1 month after implantation. During the first test (T1) the pacemaker was programmed to the DDD mode and heart rates were recorded every 15 to 30 seconds during exercise and 30 minutes after exercise. Following 30 minutes of rest, the implanted pacemaker was programmed to the VVT mode and driven by an external pacemaker via a skin electrode. The second exercise test (T2) was then performed and the rate of the external pacemaker was progressively changed to reproduce exactly the rate observed during T1 at the same exercise stress. Atrial natriuretic factor (ANF) levels were determined at rest, at regular intervals during exercise, and 30 minutes after exercise. ANF levels and release were statistically higher during rate matched ventricular, than DDD pacing. It is concluded that preservation of AV synchrony reduces ANF release induced by heart rate acceleration during exercise.

Aged↗