PubMed Health⌕ Search

Biomedical subjects

H Bechtold

Publications and source records attributed to H Bechtold.

36 records · Page 2Linked to original sources

[Diagnosis of thoracic aortic aneurysms with 2-dimensional echography].

Eight patients with thoracic aortic aneurysms were investigated by angiography, computed tomography and two-dimensional echography. According to results of computed tomography or angiography six patients had a dissecting aortic aneurysm (five patients type 1 and one patient type 3 according to DeBakey) and two patients had a thoracic aortic aneurysm without dissection. In addition, thrombi in the descending aorta were shown in three patients by computed tomography or by angiography. Type and extent of the aneurysms could be evaluated by two-dimensional echography in all patients. Only in one patient could the origin of dissection in the ascending aorta not be localised precisely by echography. In three patients thrombi in the descending aorta could be demonstrated. For assessment of type and extent of the aneurysm the suprasternal approach was superior to precordial, subcostal and apical imaging. Parasternal investigation resulted in echographic demonstration of dissection in only two cases. Two-dimensional echography is a technically less demanding and useful method in the diagnosis of thoracic aortic aneurysms.

Adolescent↗

[Incidence and clinical significance of ventricular arrhythmias in dilated cardiomyopathy].

The diagnosis of dilated (congestive) cardiomyopathy was made in 75 patients on the basis of clinical, ECG, echo and angiographic-haemodynamic findings. Ambulatory 24-hour monitoring was undertaken in all patients. Nearly all of them (93%) had ventricular extrasystoles (VES), 35% more often than 1000/24 h. In 15% VES occurred in pairs, in 44% as ventricular tachycardia. In general, frequent VES (greater than 30/h) also came in pairs and/or as ventricular tachycardia. On the other hand, not all patients with such complex arrhythmias also had frequent VES. In about 70% of all patients with ventricular tachycardia such episodes were registered repeatedly, in more than 40% more than five tachycardia episodes per 24 hours. In the majority of patients the tachycardia consisted of three (33%), four (12%) or five (18%) consecutive ventricular complexes. All episodes of ventricular tachycardia ended spontaneously and were clinically largely silent. Apparently there was no clinically relevant correlation between frequency and severity of the arrhythmia, on the one hand, and extent of abnormal ventricular function, on the other. These findings indicate that frequent and complex ventricular arrhythmias are a characteristic feature of dilated (congestive) cardiomyopathy. If they occur in heart disease of seemingly unknown aetiology, dilated cardiomyopathy should be suspected. Preliminary findings of long-term observation indicate that patients with frequent ventricular tachycardias have a higher risk of sudden death.

Adolescent↗

Isosorbide dinitrate kinetics and dynamics after intravenous, sublingual, and percutaneous dosing in angina.

Isosorbide dinitrate (ISDN) kinetics and dynamics were examined after various routes of administration for angina. Given intravenously, ISDN kinetics were apparently linear over the range of infusion rate (0.083 and 0.133 mg/min) and duration (15 min and 1 and 2 hr) studied. Mean +/- SD systemic clearance of ISDN was 3.4 +/- 1.4 l/min and volume of distribution (VdSS or Vdarea) about 100 l. These data are consistent with the presence of extensive extrahepatic metabolism. In six patients, sublingual ISDN (5 mg) was also given and mean bioavailability of 59% (19% to 93%) for this route was determined. For this group, sublingual absorption of intact ISDN was incomplete and variable. The presence of a longer disappearance t 1/2 after sublingual dosing suggested that the input process may be rate limiting. After percutaneous application of a topical formulation (100 mg over an area of 400 cm2), steady-state plasma concentrations at about 7 ng/ml were maintained from 6 to 24 hr. The bioavailability of the topical application was estimated at 30%. At the doses given, intravenous ISDN had no apparent effect on heart rate but induced significant reduction in standing systolic blood pressure. The effect vs the ISDN concentration profile was described by a hysteresis loop, indicating that changes in blood pressure response lag behind changes in plasma ISDN concentration. After intravenous dosing, peak plasma ISDN concentration and peak effect (maximum change in standing systolic blood pressure). At the doses used, both sublingual and percutaneous ISDN induced less distinct circulatory changes than the intravenous infusion.

Absorption↗

Alinidine in angina.

Alinidine--N-allyl-clonidine--reduces heart rate without blocking beta adrenoreceptors. It may be used in patients with angina without inducing the adverse effects of beta-adrenergic blockers. We therefore evaluated alinidine efficacy in patients with angiographically proven coronary artery disease and stable angina during a 10-wk placebo-controlled randomized double-blind trial. Alinidine (40 mg three times a day) reduced the number of anginal attacks and the average number of nitroglycerine capsules consumed. The double product was slightly lowered during rest but more pronounced during exercise. This effect was mainly due to decreased heart rate. The ischemic S-T segment depression was diminished. Exercise tolerance was clearly improved in six, slightly improved in two, and unchanged in four subjects.

Adult↗

Cyclic interconversion of vitamin K1 and vitamin K1 2,3-epoxide in man.

The disposition of a single intravenous bolus dose of 10 mg vitamin K1 and vitamin K1-2,3-epoxide were studied in two healthy subjects without and with 12 h pretreatment dose of phenprocoumon (0.4 mg/kg). For each compound administered alone the plasma concentration-time profile was adequately fitted by a biexponential equation, with an average terminal half-life of 2.0 and 1.15 h for the administered vitamin K and its 2,3-epoxide respectively. While vitamin K1 was measurable in plasma following administration of vitamin K1-2,3-epoxide, the epoxide was not detectable following administration of vitamin K1. Following pretreatment with phenprocoumon and after intravenous administration of vitamin K1, both the average half-life and area under the plasma concentration-time profile of vitamin K1 were marginally reduced to 1.5 h and 1.76 mg l-1 h respectively, while the plasma concentration of vitamin K1-2,3-epoxide was readily measurable and its half-life markedly prolonged to 14.7 h. Following pretreatment with phenprocoumon and after oral administration of vitamin K1-2,3-epoxide, no vitamin K1 was detectable in plasma and the half-life of the epoxide was 13.8 h. Based on area considerations the data suggest that either phenprocoumon does more than just inhibit the reduction of vitamin K1-2,3-epoxide to vitamin K1, or that the simple model describing the interconversion between vitamin K1 and its epoxide is inadequate. The same conclusion is drawn from the analysis of comparable data in dogs, obtained by Carlisle & Blaschke (1981).

Adult↗

[Separation of the left atrium from the right pulmonary artery in the suprasternal echocardiogram: a parameter of left atrial pressure].

A separation of the left atrium from the right pulmonary artery during atrial contraction may be observed in the suprasternal echocardiogram. In 280 catheterized patients with sinus rhythm, we investigated whether left atrial separation is a parameter from which an estimate of the left atrial pressure can be obtained. In 239 of the 280 patients, the suprasternal echograms were of a quality such that it could be seen whether there was, a left atrial separation. In 182 patients, a normal left atrial pressure (greater than or equal to 12 mm Hg) was found; in 57 patients, the left atrial pressure was elevated. An atrial separation was observed in 183 patients, and in 56 patients it was lacking. Lack of left atrial separation indicates a left atrial pressure elevation with a sensitivity of 73.7% and a specificity of 92.3%. If a left atrial pressure above 18 mm Hg was considered elevated, the sensitivity of this echoparameter amounted to 90.3%, and the specificity was 86.5%. The study shows that the left atrial separation from the right pulmonary artery separation from the right pulmonary artery in the suprasternal echocardiogram is a parameter valuable in providing a rough estimate of the left atrial pressure.

Blood Pressure↗

[Importance of echocardiography for the assessment of left-ventricular function and cardiac complications in dilative cardiomyopathy].

One- and two-dimensional echocardiographic findings in 17 patients with dilated cardiomyopathy were compared with haemodynamic and angiographic results of cardiac catheterization. In a further 52 unselected patients with dilated cardiomyopathy, who had been seen as out- or in-patients over a period of two years, the frequency of intracardiac thrombi was investigated echocardiographically. A significant correlation (r = 0.66 and r = 0.68) was found between echocardiographically determined left-ventricular end-diastolic and end-systolic volumes on the one hand and volumes determined angiographically on the other. However, ventricular volumes were clearly underestimated by echocardiography. In contrast, both methods showed good agreement for the magnitude of the ejection fraction (r = 0.79). The aortic valve opening surface estimated with one-dimensional echocardiography correlated with left-ventricular ejection volume (r = 0.93). Thrombi were demonstrated in 7 out of 52 patients: 5 were located in the left, one in the right and a further one in the central pulmonary vascular system. Considering the aforementioned limitations, echocardiography is a useful method for evaluation of left-ventricular function and for demonstration of intracardiac thrombi in dilated cardiomyopathy.

Adolescent↗

Comparison of the antiarrhythmic activity of mexiletine and lorcainide on ventricular arrhythmias.

In a blind cross-over study, 12 patients with ventricular arrhythmias (VPC's; Lown Grades II-IVB) resistant to a daily dose of quinidine 1.2 g, disopyramide 0.8 g, N-propyl-ajmaline 0.1 g were randomly given, each dose for one week, placebo (PL), mexiletine (MEX; 400, 600, 800 mg daily) and lorcainide (LOR; 200, 300, 400 mg daily). On the last day of each treatment period, patients were evaluated by 24-h continuous ambulatory monitoring, 6-channel surface ECG, plasma concentrations and side-effects. During PL I (before) and PL II (after drug treatment), the mean number of VPCs per hour was 670 and 701. VPCs were reduced in 5 of the 12 patients with MEX by 43% (400 mg), 74% (600 mg) and 91% (800 mg). VPCs were reduced in 10 patients with LOR by 60% (200 mg), 78% (300 mg) and 93% (400 mg). Log. lin. plasma conc. effect relationships were constructed for MEX and LOR. Vomiting, nausea, and abdominal pain were seen in 2 patients with MEX; insomnia and feeling heat in 10 patients with LOR. At the end of the LOR-treatment, these side-effects were less in 5 and absent in 5 patients. In this study, LOR seems superior to MEX in refractory ventricular arrhythmias.

Adult↗

Haemodynamic effects of a single intravenous dose of lorcainide in patients with heart disease.

The cardiovascular effects of a single i.v. dose (2 mg/kg over 5 min) of lorcainide were studied in 14 patients with heart disease. In the haemodynamic part of the study (6 patients), the aortic and pulmonary systolic, diastolic and mean pressures, left ventricular systolic and end-diastolic pressures, cardiac output and the rate of rise of left ventricular pressure were measured before and for 30 min after administration of the drug. Lorcainide produced a slight and short-lasting decrease in the aortic and pulmonary systolic pressures, and all other pressure values remained unchanged. The cardiac output and systemic vascular resistance were not altered by lorcainide. It consistently depressed the rate of rise of left ventricular pressure (maximum mean decrease 19%). In the angiographic part of the study (8 patients), the ejection fraction and the mean velocity of circumferential fiber shortening were measured before and 5 min after lorcainide. In all but one patient, lorcainide decreased the ejection fraction (mean decrease 11.6%), and the mean velocity of circumferential fiber shortening was uniformly diminished by lorcainide (mean decrease 29.7%). Thus, lorcainide moderately impaired myocardial performance in patients with normal and reduced left ventricular function without producing hypotensive side effects.

Adult↗

Antiarrhythmic effect of lorcainide during chronic treatment.

The effect of oral N-(4-chlorophenyl)-N-[1-(1-methylethyl)-4-piperidinyl]benzene acetamide (lorcainide) was studied in 12 patients with frequent and stable ventricular arrhythmias resistant to a number of other antiarrhythmic agents. Ambulatory electrocardiograms were obtained before and during treatment with lorcainide and in some patients after discontinuation of the drug. Lorcainide suppressed ventricular premature contractions by more than 90% in all but one patient. The daily doses were 200 mg (N = 8), 300 mg (N = 1), 400 mg (N = 1)and 600 mg (N = 2). Plasma concentrations of lorcainide and of the dealkylated metabolite ranged from 0.13 to 0.27 microgram/ml and 0.25 to 0.95 microgram/ml, respectively. Side effects such as insomnia and excessive perspiration were seen in 7 and 3 patients, respectively. Lorcainide is an effective antiarrhythmic agent against ventricular arrhythmias otherwise difficult to treat.

Adult↗

Alteration of hemostasis associated with cefoperazone treatment.

21 Patients with normal and impaired renal function were given cefoperazone in a recommended dose of 4 g/day, irrespective of renal function. Platelet function and plasmatic coagulation were analyzed before and on day 7 of therapy. In patients with normal renal function on their usual diets, there was neither impairment of platelet function nor plasmatic coagulation. High serum antibiotic trough levels, prolongation of bleeding time and decreased vitamin K-dependent coagulation factors, as verified by the prolongation of prothrombin time and the appearance of descarboxyprothrombin, could be observed in those patients with impaired renal function whose insufficiency was far advanced and accompanied by a complex clinical picture. In this situation vitamin K deficiency may be due to poor oral intake, along with interference of hepatic vitamin K metabolism, showing an effect similar to that seen after coumarin therapy. Dosage reduction of the antibiotic in advanced renal failure and repeated control of prothrombin time is advised.

Adenosine Diphosphate↗