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P Stelzer

Publications and source records attributed to P Stelzer.

At least 19 recordsLinked to original sources
PubMed1996

[The effect of timing of labor induction on the occurrence of congenital myofibrillar hypoplasia--short clinical report].

In an intensive pig production unit with routinely performed prostaglandin partus induction four groups of sows were formed shortly before parturition. The animals received 3 mg alfaprostol as a single intramuscular injection each. The sows of group 1 on the 112th, those of group 2 on the 113th and the animals of group 3 on the 114th day of pregnancy. Group 4 sows were not treated and formed the control group. We evaluated the number of live born piglets and the number of piglets born with congenital myofibrillar hypoplasia. The results showed no significant difference regarding live born piglets. As regards congenital myofibrillar hypoplasia the sows with early partus induction (group 1) showed significant higher incidence when compared to the other groups. It is likely that in cases of partus induction before the 113th day of pregnancy the fetus is still insufficiently protected by natural maturation, adaptation and tolerance ability against such congenital condition as CMH. Therefore it is the opinion of the authors that partus induction before the 113th day of pregnancy should not be performed.

Animals↗
PubMed1996

[Management of E. coli dependent factorial diseases in weaning piglets].

The most important postweaning factorial diseases are at least partly caused by E. coli. The term postweaning coli complex can be subcategorized into the following manifestations: postweaning diarrhoea, edema disease, postweaning wasting and hemorrhagic gastroenteritis. In the presented study the effect of prophylactic zootechnique alone and zoo- and biotechnique in combination was evaluated during the first weeks postweaning. The results showed that combined zoo- and biotechnique is superior to simple zootechnique regarding food conversion (1.41 kg versus 1.73 kg), average daily weight gain (390 g versus 325 g) and postweaning piglet mortality (3.1% versus 4.9%). It is the opinion of the authors that combined postweaning zoo- and biotechnique should be performed in such pig production units where ETEC and/or SLTEC are present.

Animal Feed↗
PubMed1994

Hemodynamic compromise secondary to a mediastinal bronchogenic cyst.

Bronchogenic cysts are not commonly the cause of severe symptoms, and often present only as an abnormality on chest roentgenogram. We report an unusual patient with a mediastinal bronchogenic cyst associated with rapid hemodynamic deterioration secondary to compression of vital structures.

Adult↗
PubMed1992

Pulmonary autograft replacement in children. The ideal solution?

Fifty-one children, aged 1.8 to 21 years (mean, 11.4) with aortic valve replacement using a pulmonary autograft are reviewed. Twenty-nine were intra-aortic implants and 22 were root replacements. There was one operative death, no late deaths, and two have required reoperation. Actuarial freedom from reoperation was 93% +/- 5.5 at 5.6 years. Freedom from progression of aortic insufficiency (AI) was 81% +/- 9 at 5.6 years in the intra-aortic implants and 86% +/- 10 in the root replacement. Enlargement of the pulmonary autograft was seen echocardiographically in both groups. This enlargement was consistent with somatic growth and not associated with progression of AI. Ten of 19 patients with aortic stenosis had an LV mass index suggestive of LV hypertrophy before operation. At 1 year, 18 of 25 had a normal LV mass index. Thirteen of 16 patients with AI had preoperative abnormal LV mass index. All but four returned to normal by 1 year. Low operative risk, excellent function, resolution of abnormal LV hemodynamics, and enlargement consistent with somatic growth suggest that the pulmonary autograft is the ideal replacement for the malfunctioning aortic valve.

Adolescent↗
PubMed1992

Pulmonary autograft replacement of the aortic valve: an evolution of technique.

The use of the patient's pulmonary valve for replacement of the patient's diseased aortic valve was introduced and developed by Mr. Donald Ross. Its demonstrated durability, freedom from thromboembolism, and potential for growth has led to increased utilization of this technique. Modifications of the earlier techniques have led to a reproducible operation with low operative risk and excellent mid-term results.

Aortic Valve↗
PubMed1992

Transcranial Doppler sonography monitoring of local intra-arterial thrombolysis in acute occlusion of the middle cerebral artery.

BACKGROUND AND PURPOSE: The aim of this study is to report on the use of transcranial Doppler ultrasonography as a noninvasive diagnostic monitoring tool during local intra-arterial thrombolysis in a patient with acute embolic occlusion of the middle cerebral artery. CASE DESCRIPTION: We describe a 41-year-old woman with mitral valve stenosis suffering from embolism of the middle cerebral artery. Local thrombolysis was performed with tissue plasminogen activator at a dosage of 0.05 mg/kg/hr. Progress of the thrombolysis was monitored by transcranial Doppler. The steps of recanalization could be ascertained by transcranial ultrasound showing a hemodynamically relevant residual stenosis after the first 120 minutes and complete patency of the M1 segment of the middle cerebral artery 180 minutes later. One branch of the middle cerebral artery still showed a filling defect. CONCLUSIONS: Our report demonstrates the potential usefulness of transcranial Doppler monitoring during thrombolysis of a proximal occlusion of the middle cerebral artery for guiding the treatment by assessing the reperfusion of the obstructed artery.

Acute Disease↗
PubMed1991

Replacement of the abdominal aorta with an aortic homograft in a patient with an aortic dissection.

The use of aortic and femoral homografts in early vascular surgery has been abandoned for the more successful and abundant synthetic substitutes. With the recent introduction of cryopreservation, homograft use has again met with improved success. A 40-year-old man who had a DeBakey Type I aortic dissection initially underwent replacement of the aortic root with a pulmonary homograft. Subsequently, in the presence of an intraabdominal infectious process, progressive mesenteric and lower limb ischemia was treated by replacing the abdominal aorta with an aortic homograft. Thirty-six months postoperative the patient has a functioning gastrointestinal tract and no vascular insufficiency of the lower extremities and no evidence of degeneration of the homograft. Further laboratory studies should be undertaken using the newer and improved cyropreserved homograft in the presence of, or potential for, an intraabdominal infectious process.

Adult↗
PubMed1991

Normal left ventricular function following pulmonary autograft replacement of the aortic valve in children.

To assess growth potential and hemodynamic sequelae of pulmonary autograft valves implanted into aortic outflow tracts of children, we reviewed our experience with 37 patients (2-21 years) from August 1986 to December 1990. Twenty patients had predominantly aortic stenosis (AS), and 17 had aortic insufficiency (AI). Operative mortality was 3%. Two technical failures required reoperation. Of survivors, six (18%) have moderate AI. Pre- and postoperative echocardiograms were reviewed. The AS group showed increased left ventricular (LV) cavity size by greater than 1-year follow-up, and decreased LV wall and interventricular septal thickness. In the AI group, wall and septal thickness increased by 10 days and LV cavity decreased by 10 days, 60 days, and greater than 1 year. Root replacements (n = 14) showed mean increases of 4.3 mm and 5.3 mm, respectively, in diameters of the aortic annulus and aortic sinuses at greater than 1 year. Intraaortic implants increased 3.1 mm (annulus) and 3.9 mm (sinuses) at greater than 1 year. The pulmonary autograft procedure is safe, and successful implantation normalizes LV dimensions and function rapidly. The autograft valve shows evidence of growth at greater than 1 year postoperative. The pulmonary autograft may be the ideal valve replacement in children.

Adolescent↗
PubMed1989

Aortic valve and left ventricular outflow tract replacement using allograft and autograft valves: a preliminary report.

A comparison of allograft and autograft (pulmonary) replacement of the aortic valve has, to our knowledge, not been done in America. Fifty-seven patients (age range, 2 to 70 years; mean age, 30 years) underwent 59 operations for replacement of the aortic valve (20) or entire left ventricular outflow tract (39) using autograft (35) or allograft (24) valves. Many had undergone a previous operation (25) or had concomitant procedures (13). Postoperative mortality was 8.5% (5/59). Two deaths occurred in the allograft group and three in the more complex pulmonary autograft group. One late death occurred. One autograft was replaced with an allograft 7 months postoperatively for severe aortic regurgitation. There have been no episodes of either endocarditis or thromboembolism. Forty-nine of 51 survivors are in New York Heart Association class I. Preliminary results suggest that congenital or acquired disease of the left ventricular outflow tract and aortic valve can be safely and effectively treated with either allograft or autograft valve transplantation.

Adolescent↗
PubMed1989

Aortic root replacement with pulmonary autograft.

Transfer of the pulmonary valve to the aortic position has been used successfully by Ross for more than 20 years and in our own institution since August 1986. To expand the use of this concept to patients with root disease and/or narrow annulus, we employed the main pulmonary artery with its valve as a conduit to replace the proximal ascending aorta, reimplanting the coronary ostia into the pulmonary trunk. Seventeen patients, aged 2-62 years, underwent the procedure with three deaths. Hemorrhage precipitated each death, and there was one reexploration for control of bleeding. Postoperative echocardiography showed excellent valvular function. No anticoagulants were used except daily aspirin in three patients who underwent concomitant procedures. There were no thromboembolic episodes. Right ventricular outflow tract reconstruction was accomplished with cryopreserved aortic (three) and pulmonary (14) allograft conduits. This operation has potential for superior long-term results in complex aortic valve disease.

Adult↗
PubMed1988

New catheter technique for recording left free-wall accessory atrioventricular pathway activation. Identification of pathway fiber orientation.

The ability to record accessory atrioventricular (AV) pathway activation consistently may be uniquely beneficial in improving pathway localization, identifying anatomic relations, and providing insight into unusual conduction properties. For the purpose of recording left AV accessory pathway activation, an electrode catheter was specially designed for use in the coronary sinus. The orthogonal catheter has three sets of four electrodes spaced evenly around the circumference. Electrograms were recorded at low gain (less than 1 cm/mV) between adjacent electrodes on the same set (interelectrode distance, 1.5 mm, center to center). This provides a recording dipole perpendicular to the atrioventricular groove to enhance recording of accessory pathway activation while minimizing overlapping atrial or ventricular potentials. The orthogonal electrode catheter was used in the electrophysiological study of 48 consecutive patients with 59 left AV accessory pathways. The catheter could be advanced along the coronary sinus beyond the site of earliest retrograde atrial activation in 49 of the 59 accessory pathways. Activation potentials were recorded from 45 of the 49 (92%) accessory pathways accessible to the catheter (5 of 5 anterior, 8 of 8 anterolateral, 15 of 16 lateral, 5 of 5 posterolateral, 5 of 5 posterior, and 7 of 10 posteroseptal). Accessory pathway potentials were validated by dissociating them from both atrial and ventricular activation by programmed-stimulation techniques. During surgery, accessory pathway potentials were identified from orthogonal catheter electrodes in the coronary sinus in 14 of 16 accessory pathways (12 patients). Epicardial mapping confirmed the location of the accessory pathway, and direct pressure over the orthogonal catheter electrode that recorded the accessory pathway potential resulted in transient conduction block in nine of the 14 accessory pathways. Orthogonal electrode maps of the coronary sinus identified an oblique course in 39 of 45 recorded accessory pathways. Thirty-two of 38 left free-wall accessory pathways were oriented with atrial insertion 4-30 mm (median, 14 mm) proximal (posterior) to the ventricular insertion. In the remaining six free-wall accessory pathways, the lateral excursion could not be determined because either only the atrial end of the accessory pathway was recorded or activation of multiple pathway fibers prevented tracking of individual strands. The seven recorded posteroseptal pathways exhibited accessory pathway potentials throughout an 8-18-mm (median, 10 mm) length of the proximal coronary sinus, but fiber orientation was difficult to determine.(ABSTRACT TRUNCATED AT 400 WORDS)

Atrioventricular Node↗
PubMed1987

Pulmonary autograft: an American experience.

Pulmonary valve autograft replacement of the aortic valve has been performed in nine patients in an effort to duplicate in the United States the experience of Sir Donald Ross in London. Four male and five female patients ranging in age from seven to thirty-four years have been operated on for indications of aortic stenosis in six and aortic regurgitation in three. Three patients had associated procedures performed concomitantly. All patients survived the surgery and were clinically improved, however, one patient did require reoperation for progressive aortic insufficiency. Specific indications, results, and technical considerations are discussed and illustrated.

Adolescent↗
PubMed1986

Inappropriate ventricular blanking in a DDI pacemaker.

The DDI mode is a new pacing mode with potential advantages over DVI pacing. We describe anomalous post R wave ventricular pacing due to the presence of inappropriate ventricular blanking periods in a pacemaker programmed to the DDI mode. Although no adverse consequences were seen in our patients, potentially dangerous R-on-T pacing could occur, particularly if long atrioventricular delays are programmed. A method for eliminating this pacing anomaly is described. Patients programmed to the DDI mode with the pacemaker model described should be evaluated for post R wave ventricular pacing and corrective measures should be taken.

Aged↗