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K Seidl

Publications and source records attributed to K Seidl.

At least 73 records · Page 4Linked to original sources
PubMed1997

[High frequency catheter ablation as therapy of symptomatic ventricular extrasystole].

Ventricular ectopic activity is commonly encountered in clinical practice. Usually it is not associated with life-threatening consequences in the absence of significant structural heart disease. However, frequent ventricular ectopic beats can be highly symptomatic and even incapacitating in some patients. Currently, reassurance and pharmacological therapy are the mainstays of treatment. This study assesses the useful role of catheter ablation in eliminating drug refractory monomorphic ventricular ectopic beats in severely symptomatic patients. Eight patients were included, five patients had no heart disease and in three patients a structural heart disease was present (coronary artery disease in 1, hypertensive heart disease in 1, mitral valve prolaps in 1). The ejection fraction was higher than 40% in all patients (mean EF 56 +/- 14%). Mean number of ventricular ectopic activity was 29,295 +/- 10,650 VPB/24 h (1209 +/- 457 VPB/h) before ablation. No other spontaneous or induced arrhythmias were documented. The site of origin of ventricular ectopic activity was accurately mapped by using earliest endocardial activation time during ectopic activity or pace mapping, or both. The ectopic focus was located in the right ventricular outflow tract in five patients and in the left ventricle in three patients (posteroseptal 2, anterolateral 1). Frequent ventricular ectopic beats were successfully eliminated by catheter ablation in all patients. Early recurrence occurred in one patient after 10 min and 30 min after the procedure. In another patient a recurrence occurred 6 days after the procedure. In a second session he was successfully ablated and remained free of recurrence since 2 months. After ablation the mean number of ventricular premature beats was 211 +/- 159 VPB/24 h (9 +/- 7 VPB/h). The mean number of radiofrequency applications was 8 +/- 7 (range 2-22). Mean radiation time was 12 +/- 8 min. No complications were observed. During a mean follow-up of 6 months there were no further recurrences in the remaining six patients. Radiofrequency catheter ablation can be successfully used to eliminate monomorphic ventricular ectopic activity. It may therefore be a reasonable alternative for the treatment of severely symptomatic, drug resistant monomorphic ventricular ectopic activity.

Adult↗
PubMed1997

[Balloon dilatation in acute myocardial infarct in routine clinical practice: results of the register of the Working Society of Leading Cardiologic Hospital Physicians in 4,625 patients].

Balloon angioplasty as the treatment of first choice in the setting of an acute myocardial infarction (AMI) is gaining widespread acceptance because of favourable results from specialised centres concerning high patency rates and low mortality. This study reports the results of angioplasty for AMI at large community hospitals during 1992-1995. 4625 procedures were performed at 68 centres of the Arbeitsgemeinschaft Leitender Kardiologischer Krankenhausärzte (ALKK). The age of the patients was 60.8 +/- 11.3 years, with 75.1% men. The infarct related artery was the left anterior descendent in 43%, the right coronary artery in 37%, the circumflex artery in 16%, a bypass graft in 2.3% and the left main stem in 1.4% of patients. The success rate (residual stenosis < 50%) of the intervention was 86%. There was a wide range of procedures per centre, with a median of 40 AMI angioplasties per year and centre. The amount of angioplasties for AMI in relation to all angioplasties performed during this period rose from 5.2% in 1992 to 5.9% in 1995 (p = 0.01). Local complications at the puncture site occurred in 3.2%, with the need for a surgical intervention in 1.1% of patients. In 273 (5.9%) of the patients a second angioplasty was performed during the hospital stay. Aortocoronary bypass surgery was performed in 3% of the patients. Hospital mortality was 9.5% (438/4625 patients). The mortality rate remained constant during the years investigated (1992: 10.6%; 1993: 8.6%; 1994: 9.7%; 1995: 9.8%; p = ns). Higher mortality was observed in older patients, patients with multiple vessel disease, the left anterior descending artery or a bypass graft as infarct related artery as well as in patients with failed reperfusion (residual stenoses > 50%). Hospitals with a case load of more than 40 angioplasties for AMI per year showed a lower mortality as compared to the others. In clinical practice at large community hospitals results of angioplasty for AMI concerning mortality, complications and technical success rate are comparable to those of highly specialised centres. The absolute numbers of angioplasties for AMI increased constantly over the years.

Aged↗
PubMed1997

Local venous thrombosis after cardiac catheterization.

Pulmonary embolism is a rare but life-threatening complication of cardiac catheterization. Underlying deep venous thrombosis (DVT) is often not detectable clinically. To determine the true incidence of DVT the authors prospectively studied 450 consecutive patients (29% women, 71% men, mean age: fifty-eight years) undergoing a diagnostic cardiac catheterization. Patients were examined clinically and by duplex sonography with a high-resolution (5 or 7.5 MHz) transducer before and twenty-four hours after catheterization before mobilization. Duplex sonography excluded complete proximal DVT in all patients. Only partial occluding thrombi (pDVT) were detected in 11 (2.4%) patients. The thrombi were always localized at the puncture site. In 2 patients a difference was found in the circumferences of the legs, but no other clinical signs of DVT were seen. With use of continuous wave (cw) Doppler sonography, only 3 of these 11 patients (27%) showed a spontaneous (s) sound. Phlebography was performed in 4/11 patients (36%). In 2 patients the diagnosis was confirmed; in 1 patient extravenous compression was assumed, and the other demonstrated a normal-appearing phlebography at the time of investigation. Logistic regression analysis yielded a 3.5 times higher risk for developing a pDVT if a venous puncture was performed in addition to arterial puncture. Furthermore a 9.8 times higher risk was found if more than one venous puncture was necessary. During the follow-up no patient developed clinical signs of pulmonary embolism. The results of this study demonstrate that DVT is a rare complication of cardiac catheterization (0/450 patients), but pDVT occurred in 2.4%. Risk factors for pDVT are the venous puncture itself and multiple puncture attempts. Clinical relevance of pDVT remains to be determined.

Cardiac Catheterization↗
PubMed1996

Chick NKx-2.3 represents a novel family member of vertebrate homologues to the Drosophila homeobox gene tinman: differential expression of cNKx-2.3 and cNKx-2.5 during heart and gut development.

NKx homeodomain proteins are members of a growing family of vertebrate transcription factors with strong homology to the NK genes in Drosophila. Here, we describe the cloning of cNKx-2.3 and cNKx-2.5 cDNAs and their expression during chick development. Both genes are expressed in the developing heart with distinct but overlapping spatio-temporal patterns. While cNKx-2.5 is activated in early precardiac mesoderm and continues to be uniformly expressed throughout the mature heart, expression of NKx-2.3 starts later in differentiated myocardial cells with regional differences compared to NKx-2.5. Additionally, both genes are expressed in adjacent domains of the developing mid- and hindgut mesoderm as well as in branchial arches. The highly conserved structure of cNKx-2.5 and its similar expression to mouse and Xenopus NKx-2.5 genes and to the Drosophila gene tinman argue that it constitutes the chick homologue of these genes. Different temporal and spatial activity of cNKx-2.3 in heart and gut as well as in a regionally restricted expression domain in the neural tube suggest that cNKx-2.3 is a member of the NK-2 gene family which may be involved in specifying mesodermally and ectodermally derived cell types in the embryo.

Animals↗
PubMed1996

Expression of nerve growth factor and neurotrophin receptors in testicular cells suggest novel roles for neurotrophins outside the nervous system.

The present study was designed to clarify the non-neurotrophic role for neurotrophins in mouse testis. By means of SI nuclease protection assay we could demonstrate that the gene coding for the low-affinity nerve growth factor (NGF) receptor p75NGFR is transiently expressed during germ cell development. Gene expression for p75NGFR was detected in late-meiotic spermatocytes and early spermatids and was found to be co-expressed with trkB and trkC, two tyrosine kinase receptors, commonly regarded as the high-affinity receptors for brain-derived neurotrophic factor and neurotrophin-3. Gene transcripts for the high-affinity NGF receptor trkA were found exclusively in non-germ cells. Isolated Leydig cells, peritubular myoid cells and Sertoli cells, but not germ cells, could be identified as potential testicular NGF sources. Non-germ cells respond after incubation for several days with a sharp induction in NGF synthesis, which is accompanied by a loss of phenotypic expression patterns. The fact that p75NGFR mRNA expression was induced in cultured Sertoli cells and peritubular myoid cells suggests an autocrine mode of NGF action in these cells. Induction of NGF synthesis in cultured Leydig cells could be prevented by the glucocorticoid dexamethasone. Results indicate different roles for the individual neurotrophins in distinct testicular compartments and suggest that these neurotrophins might support testicular functions by signalling between individual cell types in an autocrine and paracrine manner.

Animals↗
PubMed1996

[Feasibility and safety of dobutamine stress echocardiography: experiences with 1,000 studies].

The use of dobutamine stress echocardiography for the evaluation of coronary artery disease is rapidly expanding. Despite its widespread use, the feasibility and safety of dobutamine stress echocardiography has not been sufficiently documented. Between November 1992 and June 1995, we performed 1000 dobutamine stress echocardiographies. There were 744 men and 256 women with a mean age of 59 +/- 11 years. Anti anginal medication was not routinely withdrawn before the test. The mean maximal dobutamine dose was 41,4 +/- 10 mu g/kg center dot min(-1). Atropine was given additionally in 440 patients, with a mean dose of 0.5 mg. In patients receiving beta-blockers additional atropine was more often necessary as compared to those not receiving beta-blockers (278/457 = 61% versus 162/543 = 30 %, p < 0.0001). Reasons for discontinuing dobutamine infusion were achievement of target heart rate (64 % of cases) and maximal dose (12 % of cases). In 791 (79,1 %) patients no side-effects of dobutamine stress echocardiography were noticed. Termination of the study because of adverse side-effects occurred in 6.6 %. A total of 103 (10,3 %) noncardiac side-effects were observed: dizziness or nausea 6.4 %, headache 1.7 %. In one patient a focal cerebral seizure occurred. 156 cardiac side-effects occurred: blood pressure decrease of more than 20 mm Hg in 25 patients, extreme palpitations in 16 patients and pulmonary edema in one case. Most common cardiac side-effects consisted of arrhythmias (11.4 %): 9.1 % ventricular and 2.3 % supraventricular arrhythmias. Most ventricular arrhythmias were less severe (uniform and multiform premature ventricular beats, ventricular bigeminy or couplets in 71 patients). Nonsustained ventricular tachycardia, with a maximum duration of 20 s, occurred in 18 patients. In one patient sustained ventricular tachycardia developed and progressed towards ventricular fibrillation. This patient could be successfully defibrillated. Supraventricular arrhythmias presented as new atrial fibrillation in 10 patients, supraventricular tachycardia in three patients, junctional rhythm with a short decline in heart rate in nine patients and a second-degree AV block in another case. Dobutamine stress echocardiography has proven to be a safe and feasible method in the diagnosis of coronary heart disease. Minor side-effects are common and sometimes unpleasant for the patient, but do not often require termination of the study. Severe side-effects are seldom (< 1 %), but nevertheless, adequate medical and technical (defibrillator) support should be rapidly available.

Adult↗
PubMed1996

Do 5-F-catheters reduce the incidence of a pseudoaneurysm?

Femoral artery pseudoaneurysm is a major problem in patients undergoing cardiac catheterization. This study describes our experience with 5 French (5 F) and 7 French (7 F) introduction sheaths and 7 investigators at our institution regarding the incidence of pseudoaneurysms. During 54 months (1/1990-6/1994) 8715 consecutive patients after diagnostic cardiac catheterization were first clinically checked for pseudoaneurysm and in case of suspicion a duplex sonography was performed. In 86 (1%) patients, 44 (52%) women and 42 (48%) men, mean age 63 +/- 9.7 years we observed this complication by duplex ultrasound. 54 (62%) patients had arterial hypertension, 18 (20%) diabetes and only 3 (3.6%) had peripheral arteriosclerosis. An antithrombotic medication was used in 60% (52 patients). As compared to a control group of 450 consecutive patients a pseudoaneurysm was significantly more likely to occur in patients with a history of hypertension (63% vs 25%, p < 0.0001). Women are also at higher risk representing 51% of all pseudoaneurysms as compared to 29% in the control group (p < 0.0001). Using 7-F catheters more pseudoaneurysms occurred (82/7183; 1%) than using 5 F (4/1532; 0.2%) introduction sheaths (p = 0.0005). There were also significantly more pseudoaneurysms caused by investigator 1 (21/787; 2.7%) as compared to the other investigators (65/7829; 0.8%), (p = 0.0002). Investigator 1 had a more distal puncture technique than the others. Pseudoaneurysms complicating cardiac catheterization occur 5-times more frequent using 7 F (1%) as compared to 5 F catheters (0.2%). Moreover distal puncture site is associated with a higher frequency of pseudoaneurysms.

Aneurysm, False↗
PubMed1996

[Renaissance of beta blocker therapy in myocardial infarct].

Beta-adrenergic blocking drugs have been evaluated for the treatment of arrhythmias and for the prevention of sudden cardia death, particularly in post-myocardial infarction patients. Betablockers have been demonstrated to reduce mortality, reinfarction, ventricular fibrillation and cardiac rupture in acute infarction. Therefore, in patients with suspected myocardial infarction and without contraindications, treatment with betablockers should be initiated early and continued for at least 2 years. Side-effects are mild and occur in approximately 10% of patients. Patients who have contraindications for betablockers use early in myocardial infarction should be reevaluated before discharge from the hospital and considered for such therapy. Because betablockers prevent some of the adverse arrhythmogenic mechanisms seen in chronic heart failure, it may be reasonable to expect that these drugs could have a role in preventing sudden cardiac death in these patients. Analysis of some of the betablocker post-infarction trials indicate that betablockers reduced the risk of sudden death in patients with heart failure at baseline. Some studies demonstrated also the symptomatic improvement following therapy with betablockers in patients with heart failure. But the currently available data are too limited to provide conclusive information.

Adrenergic beta-Antagonists↗
PubMed1995

[Cardioversion in atrial fibrillation. Results and complications in 1,152 prospective patients. Study Group of the Working Society of Leading Cardiologic Hospital Physicians].

BACKGROUND: Pharmacological and direct-current cardioversion of atrial fibrillation are often performed interventions. Little is known about results and complications of cardioversion in daily practise. PATIENTS AND METHODS: Demographic, procedural and outcome data from patients with cardioversion of atrial fibrillation were collected in a prospective, multicenter registry of 61 hospitals. RESULTS: Between July 1994 and December 1994 1152 patients with a mean age of 64 +/- 11 years were registered on an intention-to-treat basis. 62% were male. The most prevalent underlying disorders were coronary artery disease (34.7%), valvular heart disease (18.1%), and cardiomyopathy (6.9%). 16.4% of patients had lone atrial fibrillation. New onset atrial fibrillation was reported in 21%, paroxysmal in 32% and chronic in 47% of patients. The mean duration of atrial fibrillation was 7 +/- 26 weeks (range 1 day to 7 years, median 5 days). In 3.8% of patients no cardioversion attempt was made and follow-up was not possible in another 5.5%. 19.2% of patients cardioverted spontaneously. Direct current cardioversion was attempted in 39.7% and pharmacological cardioversion in 31.8% of patients. Cardioversion was successful (sinus rhythm at discharge) in 96.4% of spontaneous cardioversion, in 73.1% of direct current cardioversion and in 84.4% of pharmacological cardioversion. Success of cardioversion was significantly related to duration of atrial fibrillation, NYHA functional class and left atrial diameter (p < 0.001). In 55 (4.8%) cases complications were reported of which 14 were fatal. Five cases of sudden death occurred, all of which were related to quinidine therapy for pharmacological cardioversion. Five cases of embolism were reported. Two were not associated with cardioversion attempts and 3 occurred within 24 hours after successful direct current cardioversion. Two of these patients were effectively anticoagulated at the time of cardioversion. A total of only 62% of patients with atrial fibrillation of more than 48 hours duration were anticoagulated for cardioversion with coumadine or i.v. heparin. CONCLUSIONS: The main risks of cardioversion are fatal proarrhythmic events in pharmacological attempts to restore sinus rhythm. The risk of embolism is despite low rates of effective anticoagulation low.

Aged↗
PubMed1995

[The T-wave shock: a new reliable method for induction of ventricular fibrillation in ICD testing].

During ICD-implantation it is necessary to induce ventricular fibrillation several times to determine the defibrillation threshold. In third generation ICDs there are several options to induce ventricular fibrillation. We want to present a new method, called T-wave-shock, which is first available in the PCD Jewel 7219 (Medtronic). The T-wave-shock is the delivery of a low-energy-shock into the vulnerable period after ventricular stimulation with a basic cycle-length. We applied the T-wave-shock in 46 consecutive ICD-recipients intraoperatively and at the pre-hospital-discharge test. The method is highly effective when applying the shock into the ascending part of the T-wave (98% of the patients were inducible), and the duration of cardial and cerebral ischemia during induction is short (between 3.1 and 3.8 s). This raises defibrillation efficacy.

Adult↗
PubMed1993

Unexpected emergence of manifest preexcitation following transcatheter ablation of concealed accessory pathways.

INTRODUCTION: The basis for anterograde or retrograde unidirectional block of accessory pathways still remains a controversial issue. METHODS AND RESULTS: Four of 19 consecutive patients (1 male, 3 female; ages 27 to 34 years) who underwent transcatheter ablation of concealed accessory pathways developed manifest preexcitation after the ablation. The location of the concealed accessory pathways in these four patients were right lateral, left posteroseptal, left posterolateral, and left lateral. Radiofrequency current was used in three of the four patients and high energy direct current in one patient. After ablation, manifest preexcitation was observed in these four patients for the first time. Manifest preexcitation developed immediately after ablation in two of the four patients and after 4 and 14 days in the other two. Detailed endocardial mapping revealed that the manifest preexcitation originated from the same location as the concealed pathways. Subsequently, catheter ablation was successfully performed in three of the four patients using radiofrequency current. One patient underwent successful surgical ablation. No recurrence of preexcitation was observed during a follow-up period of 9 to 38 months. All patients remained free of arrhythmias. CONCLUSION: The basis for this unexpected emergence of preexcitation in these patients with only retrograde conducting accessory pathways deserves further investigation. Although not compared in the present study, this phenomenon has not been reported in patients who underwent surgical interruption of accessory pathways. We postulate that a lesion at the site of insertion of the accessory pathway had modified the anterograde conduction capacity.

Adult↗
PubMed1992

Basic fibroblast growth factor (bFGF) in rodent testis. Presence of bFGF mRNA and of a 30 kDa bFGF protein in pachytene spermatocytes.

We have previously described a 30 kDa basic fibroblast growth factor (bFGF)-like protein in rodent testicular homogenates and have shown that pachytene spermatocytes are the sites of predominant immunoreactivity for this bFGF-like protein (Mayerhofer, A., Russell, L.D., Grothe, C., Rudolf, M. and Gratzl, M. (1991) Endocrinology 129, 921-924). We have now addressed the question whether this 30 kDa bFGF-like protein is a large bFGF form and whether it is produced by pachytene spermatocytes. We detected bFGF mRNA in homogenates of isolated mouse spermatocytes (which consisted mainly of pachytene spermatocytes) using S1 nuclease protection assays. As shown by Western blot analyses, the bFGF mRNA in mouse spermatocytes is translated into bFGF of an approximate molecular weight of 30 kDa. Neither bFGF mRNA, nor bFGF itself, was observed in isolated mouse Leydig cells. These results indicate that the immunoreactive bFGF-like protein observed previously in germ cells of the murine testis is identical to bFGF. Thus, germ cells of the testis produce bFGF, which may exert regulatory function in the process of spermatogenesis.

Animals↗
PubMed1992

Treatment of traumatic tattoos with various sterile brushes.

BACKGROUND: Various types of brushes are efficient for the removal of foreign material accidentally projected into the skin by explosive or abrasive trauma. OBJECTIVE: To evaluate how different times between injury and treatment influenced esthetic results, we retrospectively evaluated 14 patients subjected to the brushing technique. METHODS: Two groups were identified. Group I had been treated within 24 hours of injury. In group II debridement had been performed later. RESULTS: Cosmetic results were strikingly better in group I. CONCLUSION: Our results demonstrate that debridement of traumatic tattoos should be carried out as soon as possible to achieve favorable cosmetic results.

Adult↗
PubMed1992

Leydig cells express neural cell adhesion molecules in vivo and in vitro.

The neural cell adhesion molecule (NCAM) polypeptides are expressed by numerous tissues during embryonic development, where they are involved in cell-cell interactions. In the adult, NCAM expression is confined to a few cell types, including neurons and peptide-hormone-producing cells. Here we demonstrate that the Leydig cells of the adult rat, mouse, and hamster testes express NCAM as well. Western blotting showed that an NCAM of approximately 120 kDa was present in the adult testes of all three species investigated. This form was also found in freshly isolated mouse Leydig cells and in Leydig cells after 2 days in culture. After 4 days in culture, mouse Leydig cells expressed additional NCAM isoforms of approximately 140 and 180 kDa, indicating changes in alternative splicing of NCAM primary transcripts. Also, NCAM mRNA of all isoforms, as detected by S1-nuclease protection assays, increased with time in culture. The expression of the cell adhesion molecule NCAM by adult Leydig cells may explain the aggregation of Leydig cells in clusters in rodent testes, which could be a prerequisite for functional coordination of groups of Leydig cells. Furthermore, the presence of this neural and endocrine marker may indicate a closer relationship between Leydig cells and neural and peptide-hormone-producing cells than is considered to exist at the present time.

Animals↗
PubMed1992

[Initial presentation of ventricular pre-excitation after catheter ablation of concealed retrograde conducting accessory atrioventricular pathways].

Catheter ablation using radiofrequency or direct current energy was performed in 19 consecutive patients with concealed accessory pathways. Four patients developed manifest preexcitation for the first time following ablation. The concealed accessory pathways of these four patients were localized at right lateral, left posteroseptal, left posterolateral, and left lateral sites, respectively. In two patients, manifest preexcitation developed immediately after attempted ablation. In the other two patients, preexcitation occurred after 4 and 14 days. Electrophysiologic testing revealed in all four patients that the origin of manifest preexcitation corresponded to the site of the concealed pathway. Successful catheter ablation using radiofrequency current was performed in three patients. One patient preferred surgical interruption of the accessory pathway. The reason for this sudden emergence of preexcitation of these patients with only retrograde conducting pathways remains to be investigated. The anterograde conduction capacity might have been modified by damaging the site of the accessory pathway insertion.

Adult↗
PubMed1991

Carcinoma-in-situ cells in cultured human seminiferous tubules.

For the first time, early germ-cell derived tumour cells were studied in an in-vitro system of cultured seminiferous tubules. The intratubular tumour cells not only survived in culture for 7 days but were also able to multiply. Dividing tumour cells were identified in semi-thin sections and electron micrographs by morphological criteria. Additionally, mitotic activity was demonstrated by [3H]thymidine histo-autoradiography. There are numerous reports on cell lines established from solid non-seminomas, but up to now no references to seminoma cell lines or cultures of intratubular tumour cells are available. The culture of seminiferous tubules offers a tool in making carcinoma-in-situ cells accessible for experimental work.

Autoradiography↗