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O Ickrath

Publications and source records attributed to O Ickrath.

30 records · Page 2Linked to original sources
PubMed1989

[Determination of the right ventricular ejection fraction from the exponential decrease in the thermodilution curve--a comparison with biplanar cineventriculography].

Using the exponential downslope of the thermodilution curve right ventricular ejection fraction and volumes can be calculated. To evaluate the accuracy of this method for clinical application thermodilution measurements were compared to the results of biplane cineventriculography in 40 patients. Mean right ventricular ejection fraction was 52 +/- 9% determined by thermodilution (Th), and 53 +/- 8% determined by angiography (A). Mean enddiastolic volume was 189 +/- 74 ml (Th) and 162 +/- 42 ml (A) and mean endsystolic volume 92 +/- 42 ml (Th) and 75 +/- 20 ml (A). Ejection fraction of thermodilution measurements correlated with the results of angiography (r = 0.59; SEE = 7%; % SEE = 13 rel. %; p less than 0.001). The correlation for endsystolic volume was: r = 0.50; SEE = 36 ml; % SEE = 48%; p less than 0.001, and for enddiastolic volume: r = 0.36; SEE = 70 ml; % SEE = 43%; p less than 0.05. The differences in ejection fraction calculated by the two different methods were especially high (up to 25%) in patients (n = 10) with low (less than 110 ml) or high (greater than or equal to 200 ml) enddiastolic volume. For the other 30 patients the correlation for right ventricular ejection fraction was: r = 0.82; SEE = 5%; % SEE = 9 rel. %; p less than 0.001. Thus, the thermodilution method allows an approximative assessment of right ventricular ejection fraction only in patients with a normal right ventricle. Since right ventricular ejection fraction cannot be determined with sufficient accuracy in patients with right ventricular dilatation, the clinical application of this method is limited.

Cardiac Output↗
PubMed1988

Determination of right ventricular ejection fraction by thermodilution technique--a comparison to biplane cineventriculography.

Determination of right ventricular ejection fraction (RVEF) provides information about global right ventricular function, which may be important for the management of patients with various heart diseases. Right ventricular ejection fraction can be determined by new thermodilution techniques using fast-response thermistors. To evaluate the validity of these methods, thermodilution measurements were compared with biplane cineventriculography in 22 patients undergoing cardiac catheterization. In all patients standard deviation of RVEF was below 5%. Mean RVEF, determined by thermodilution, was 52% +/- 9%, ranging from 32% to 71% and correlated significantly with the results of angiography (RVEF: 52% +/- 9%) (r = 0.80, SEE +/- 5%, n = 22, p less than 0.001). Correlation was good especially in patients with small right ventricles (less than 160 ml) (r = 0.91, SEE +/- 5%, n = 13, p less than 0.001), lower heart rates (less than 65/min) (r = 0.84, SEE = +/- 6%, n = 12, p less than 0.001) and cardiac output below 5.51/min (r = 0.88, SEE +/- 6%, n = 11, p less than 0.001). Thus, if valid catheter placement is possible, right ventricular ejection fraction can be determined by thermodilution technique with good reproducibility and sufficient accuracy compared to biplane angio. Validation of this method in larger patient populations with various heart diseases is necessary.

Aged↗
PubMed1988

[Syncope in the act of swallowing (swallowing syncope)].

In a 30-year-old female patient with recurrent syncope during swallowing, intermittent complete AV-block was documented as the underlying mechanism. This phenomenon could be provoked by inflating a balloon positioned in the lower esophagus. The His-bundle electrocardiogram, recorded simultaneously, showed a progressive increase of the normal AH-interval, up to complete block distal to the A-wave. Atropine prevented induction of the block. After implantation of a VVI pacemaker, the symptoms disappeared completely. This very rare phenomenon of swallowing syncope is probably due to a pathologic vago-vagal reflex.

Adult↗
PubMed1988

[Electrophysiologic effects of betaxolol on conduction properties of the antegrade and retrograde pathway in patients with typical atrioventricular node reentry tachycardia following intravenous and oral administration].

The electrophysiologic effects of the beta-1 selective beta adrenergic blocking drug Betaxolol were investigated after intravenous (0.15 mg/kg body weight) and oral (20 mg/day) administration in 11 patients with atrioventricular-nodal reentrant tachycardia. Betaxolol significantly (p less than 0.01) prolonged cycle length, sinus node recovery time, AH-interval, as well as the antegrade functional refractory period of the slow and fast AV-nodal pathway. The effective refractory period of the fast AV-nodal pathway was also markedly increased (p less than 0.05). In only six patients could the effective refractory period of the slow AV-nodal pathway be determined; in the other patients, it was shorter than the effective refractory period of the atrium. The effective refractory period of the atrium and the ventricle was not significantly altered by Betaxolol. Intravenous administration of Betaxolol suppressed induction of tachycardia in eight patients, whereas after oral Betaxolol, tachycardia was not inducible in ten patients. Betaxolol prevented induction of tachycardia in two patients by prolonging antegrade conduction over the slow AV-nodal pathway. The retrograde fast AV-nodal pathway was blocked in eight patients. Presumably the increased effectiveness of oral Betaxolol can be attributed to higher Betaxolol plasma concentrations, reached after oral treatment (58 +/- 38 ng/ml), as compared to intravenous administration (40 +/- 40 ng/ml). There were no false positive results after intravenous testing of Betaxolol.

Administration, Oral↗
PubMed1988

[Effect of a new class I anti-arrhythmia agent cibenzoline in patients with therapy refractory, sustained ventricular tachycardias].

The effectiveness of Cibenzoline was assessed by means of programmed ventricular stimulation in 13 patients with sustained, drug refractory ventricular tachycardia. Besides Cibenzoline, an average of 3.5 antiarrhythmic drugs were tested, or were clinically ineffective. Cibenzoline was applied, i.v., in a dose of 1.5 mg/kg within 10 min. Cycle length was significantly shortened (p less than or equal to 0.05) while increases were noted for effective refractory period of the right ventricle (p less than or equal to 0.05), intranodal (AH-interval) and infranodal (HV-interval) conduction time (p less than or equal to 0.01), QRS-duration (p less than or equal to 0.001), QT-interval corrected for frequency (p less than or equal to 0.001) as well as cycle-length of the tachycardia (p less than or equal to 0.05). After i.v. Cibenzoline, induction of tachycardia was more difficult in two patients and unchanged in five patients. Spontaneous occurrence of the tachycardia was noted in three patients, and in one patient tachycardia was sustained by atrial stimulation. Cibenzoline i.v. prevented tachycardia in two patients respectively induction of tachycardia was not reproducible. It is concluded that Cibenzoline may be effective in individual patients with sustained ventricular tachycardia unresponsive to other antiarrhythmic drugs.

Adult↗
PubMed1987

Effects of membrane plasma exchange on the hemostatic system and on thyroid hormones in critically ill patients.

The present study examined the effects of repeated plasma exchanges with membrane filtration (Plasmaflux P2 membrane, 4.3 I human albumin solution) on the hemostatic system and on thyroid hormones in critically ill patients. Clotting factors V, VII, VIII, IX, X, XI, XII, XIII, fibrinogen, antithrombin III (ATIII), prothrombin time (PT), activated partial thromboplastin time (PTT), total (TT3) and free tri-iodothyronine (FT3), total (TT4) and free thyroxine (FT4), and thyroxine binding globulin (TBG) were determined before, immediately after, 1, 3, 6 and 24 h after plasma exchange in 6 patients (3 with glomerulonephritis, 2 with IgG myeloma, 1 with chronic polyneuritis) during 18 plasma exchanges. After plasma exchange levels of clotting factors and ATIII were markedly lowered but except for fibrinogen and factor XIII, they were not reduced by repeated exchange procedures. Thyroid hormones and TBG were reconstituted after 24 h. Pre-exchange levels, except for TT4 and TBG, were not lowered by repeated exchange procedures. Risk of bleeding or thrombosis is small and there is no appreciable risk of loss of thyroid hormones during repeated plasma exchanges.

Adult↗
PubMed1984

[Spontaneous regression of residential stenosis of the infarct vessel following successful percutaneous transluminal coronary recanalization].

In 64 out of 90 patients with thrombolysis by intracoronary streptokinase (PTCR) in the acute stage of myocardial infarction coronary angiography was performed in the chronic stage after 28 +/- 20 days. 52 of 56 successfully treated patients had a patent infarct vessel in the chronic stage. 36 of these patients showed a spontaneous regression from the subacute to the chronic stage. In 49 of the 56 patients (age: 53.4 +/- 10.4 years) a residual stenosis of more than 75% after PTCR was found; in the chronic stage only 31 patients had a stenosis of more than 75%. Of 10 patients with a spontaneous regression of 25% or more (age: 48.0 +/- 14.9 years) 8 had a one-vessel disease. The infarct vessel was in 6 patients the left anterior descending, in 4 patients the right coronary artery and in no case the left circumflex branch. The results suggest that the indication for invasive interventions, such as acute coronary angioplasty or bypass surgery, does not only depend on the degree of the residual stenosis directly after reperfusion. If possible, the decision for further invasive treatment should depend on the clinical follow-up.

Adult↗
PubMedDate not supplied

Background and early results of a modified left atrial radiofrequency procedure concomitant with cardiac surgery.

With the introduction of the maze operation Cox was able to show that the surgical treatment of atrial fibrillation (AF) is feasible. However, the maze operation remains surgically demanding and time-consuming as it requires multiple incisions in both atria. This has led to the development of various modifications. With new ablative technology and the acceptable results of an exclusively left atrial maze procedure in combination with mitral valve surgery, it has become possible to simplify the maze operation radically. Thirty-one patients ( mean age 62.3 years) with chronic or intermittent AF underwent a modified radiofrequency procedure in combination with some other cardiac surgical operation. Mitral valve disease coexisted in 17 patients, aortic valve disease in 9, coronary heart disease in 4 patients and 1 had an atrial septal defect (ASD). After left atriotomy and with the use of the Thermaline radiofrequency ablator probe, bilateral pulmonary vein isolation was carried out. An additional ablation line was directed from the left pulmonary veins to the posterior mitral valve annulus, and finally the left atrial appendage was resected. The complete procedure added an average of only 18.2 minutes to the operation. In the early postoperative course AF or atrial flutter recurred in 12 patients but at discharge only 8 patients (24%) still had an arrhythmia. We concentrated on the first 26 patients of our series who had received a follow-up examination 3 months postoperatively. At discharge 18 of the 26 patients were in sinus rhythm (69,2%), and at 3 months after surgery 23 of 26 patients were in sinus rhythm (88.5%), with recovery of atrial contraction confirmed echocardiographically. Only 4 patients still required medication for arrhythmias. The modified radiofrequency ablation procedure of the left atrium proved to be simple to perform, quick and reliable. It offers the possibility of a surgical cure for AF when performed together with another cardiac operation, and the early results indicate a high rate of success for this simple procedure.

Adult↗
PubMedDate not supplied

Estradiol concentrations in premenopausal women with coronary heart disease.

BACKGROUND: Because of the beneficial effects of estrogen, premenopausal women are normally protected against coronary heart disease (CHD) and are at lower risk for myocardial infarction; consequently, CHD occurs very rarely in menstrually active women. Given this background, the aim of the present study was to test the hypothesis that decreased concentrations of estrogen are associated with CHD in premenopausal women. METHODS: Fourteen premenopausal women with CHD were investigated and compared with a healthy control group comparable for age and cardiovascular risk factors. Relevant characteristics of patients and controls were assessed: age, blood pressure, body mass index, total cholesterol and high-density lipoprotein cholesterol, triglycerides, former pregnancies, ovariectomy and related surgical interventions, smoking history and former use of oral contraceptives. To ensure the premenopausal status of the participants, the regularity of the menstrual cycle and the follicle-stimulating hormone concentrations were also assessed. Plasma estradiol and progesterone and urine estrone concentrations (24 h urine collection) were measured at day 6 after estimated ovulation to assess the relative increase in plasma estradiol and progesterone during the second half of the menstrual cycle. RESULTS: Compared with the control group, premenopausal women with CHD had significantly lower concentrations of plasma estradiol (408.9 +/- 141 pmol/l and 287.8 +/- 109 pmol/l respectively; P = 0.0228) and total estrogen (2061 +/- 693 pg/mumol creatinine and 1607 +/- 448 pg/mumol creatinine respectively; P = 0.025) in the urine. However, the progesterone concentrations were not significantly different between the groups. These findings might be explained by a partial ovarian dysfunction, as the patient group had a significantly higher number of tubal sterilizations (eight compared with one). CONCLUSION: Our data provide support for the hypothesis that decreased concentrations of estradiol might be an additional pathogenetic factor for the development of CHD in menstrually active premenopausal women.

Adult↗