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Biomedical subjects

F D Maul

Publications and source records attributed to F D Maul.

At least 55 records · Page 3Linked to original sources
PubMed1987

Radionuclide ventriculography: acute and chronic response to verapamil in patients with hypertrophic cardiomyopathy.

Eleven patients with hypertrophic cardiomyopathy were investigated by repeated radionuclide ventriculography. Nine of them were studied for the first time while under long-term treatment for 14 to 84 months. In all eleven patients radionuclide ventriculography was performed after a withdraw of verapamil for at least 14 days or before the onset of therapy respectively (control period). A third investigation was carried out 60 to 90 min after acute administration of 90 mg oral verapamil. A last radionuclide ventriculography was performed following 2 weeks of therapy with 480 mg oral verapamil. After acute administration heart rate significantly increased from 69 +/- 10 to 80 +/- 15/min. EDV was in the normal range. Left ventricular global ejection parameters showed no significant changes except for minimal decrease in ejection time from 309 +/- 29 to 278 +/- 50 ms after acute verapamil administration. The sectorial ejection fraction improved in apical sectors in relation to the basal one, while the global EF remained constant. The ventricular global peak filling rate increased significantly from 283 +/- 61 to 325 +/- 64%/EDV/s after acute administration of verapamil and the sectorial peak filling rate increased in apical sectors compared to basal sectors following acute administration as well as long-term therapy. After withdrawal of verapamil, six out of 11 patients showed a homogeneous left ventricular delay of contraction by means of the Fourier phases which were normalized under short- and long-term verapamil treatment. In conclusion, verapamil caused a marked improvement of the left ventricular contraction delay without significant changes in global systolic function.

Acute Disease↗
PubMed1986

New aspects of cellular thallium uptake: Tl+-Na+-2Cl(-)-cotransport is the central mechanism of ion uptake.

Cellular uptake mechanisms of 201Tl+ were studied in Ehrlich mouse ascites tumor cells. 201Tl+ passes the cell membrane of tumor cells using three transport systems: the ATPase, the Tl+-Na+-2Cl(-)-cotransport, and the Ca++-dependent ion channel. In the case of 201Tl+ the main route for entering the cells was the cotransport, its importance increasing with the age of the cells; in parallel, the ATPase activity was reduced. In contrast, the transport capacities of the ATPase and the cotransport were of the same magnitude in the case of 42K+ and 86Rb+. This change in ion distribution was not brought about by varying velocity relations but by changing the number of transport systems in the cell membrane. There was no relationship between transport rates and diameters of the ions. 201Tl+ distribution is proportional to that of K+ with a higher intracellular concentration of about 30%. Under physiological conditions the cotransport was reversible suggesting the ability to regulate steady state during varying extracellular ion concentrations. Cells and medium were two compartments, kinetically seen. Due to the significant difference of transport capacities between the three systems with the respective ions the term "potassium-thallium-analogy" may be misleading as it erroneously assumes identical uptake conditions.

Adenosine Triphosphatases↗
PubMed1986

[Results of combined myocardial scintigraphy and radionuclide ventriculography before and after transluminal coronary angioplasty of critical coronary artery stenoses].

This study compares exercise radionuclide ventriculography (RNVG) and exercise myocardial scintigraphy with 201Tl (MSC) both computed trisectorially. 137 patients before and after transluminal angioplasty (TCA) were investigated. While specificity equivalent was set at 90% for both methods (10% percentile of the controls [n = 29]) overall sensitivity for RNVG was 79% (n = 86) and for MSC 78% (n = 98). Sensitivity of RNVG for lesions of the posterior wall was lower than for the anterior wall: LAD stenoses 83% (n = 46), RCA stenoses 71% (n = 17), and LCX stenoses 63% (n = 8). Sensitivity of MSC presents only a slight difference between anterior and posterior wall lesions: LAD stenoses 78% (n = 51), RCA stenoses 73% (n = 22), RCX stenoses 100% (n = 8). Reproducibility of pathological findings before and after non-successful TCA and the determination of the stenosed vessel was slightly better with MSC than with RNVG. Functional improvement after a successful TCA is predictable by MSC, whereas RNVG documents the functional improvement.

Adult↗
PubMed1986

[Regional ventricular function before and after sublingual administration of nitroglycerin in patients with recent myocardial infarction in the subacute and chronic stage].

Seven patients with a recent myocardial infarction and mostly normal left ventricular end-diastolic pressure were investigated by radionuclide ventriculography after 3-4 days and three weeks before and after 1.6 mg nitroglycerin. Between day 3-4 and the third week global ejection fraction (EF) rose insignificantly (p greater than 0.05) from 31 +/- 4 to 37 +/- 6 percent. The regional EF in the non infarcted area remained nearly stable (74 +/- 5 to 85 +/- 13 relative percent, p greater than 0.05). However, the EF in the infarcted area rose from 22 +/- 9 to 38 +/- 11 relative percent (p less than 0.05 percent). On day 3-4 nitroglycerin induced a clear increase of the EF in the infarcted area from 22 +/- 9 to 35 +/- 11 relative percent (p less than 0.05). The global EF and the EF in the non infarcted area remained nearly constant (global EF from 31 +/- 4 to 34 +/- 5 percent, EF in the non infarcted area from 74 +/- 5 to 77 +/- 7 relative percent; p greater than 0.05). Three weeks after myocardial infarction 1.6 mg nitroglycerin did not produce a significant alteration of the ejection fraction (slight increase of the global EF from 37 +/- 6 to 40 +/- 6, the regional EF in the infarcted area from 38 +/- 11 to 48 +/- 11 relative percent and from 85 +/- 13 to 90 +/- 11 relative percent in the non infarcted area; p greater than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Output↗
PubMed1986

[Clinical evaluation of the tumor marker CA 19-9 in comparison with carcinoembryonic antigen (CEA) in surgical pre- and postoperative diagnosis].

A new tumor marker (CA 19-9) was investigated. CA 19-9 is a tumor-associated antigen which is detected by a monoclonal antibody. CA 19-9 (CIS-Centocor) was compared simultaneously with CEA (carcinoembryonic antigen) in 347 patients. 123 patients with gastrointestinal tumors showed a sensitivity of 31% for CA 19-9 (CEA 49%), combination increased sensitivity to 58%. The highest sensitivity was found in pancreas carcinoma (CA 19-9 75%, CEA 66%, combination 92%); it was lower in gastric, colon, and oesophagus carcinomas. In relapsed colorectal carcinomas sensitivity was 53% (CEA 78%, combination 85%). In cases of relapse, tumor markers may become positive even if they were not detectable before resection of the primary tumor. Specificity for CA 19-9 was 100% (CEA 84%) compared to a group of non-malignant diseases including patients with inflammations and patients with nicotin abuse (n = 102). Because of its high specificity and superior sensitivity to CEA in pancreas carcinomas CA 19-9 should be determined in primary and relapse diagnosis in combination with CEA.

Antigens, Neoplasm↗
PubMed1986

[Effect of captopril in chronic aortic insufficiency].

In 16 patients with chronic aortic regurgitation, we studied the acute hormonal and hemodynamic effects of 12.5 to 25 mg captopril; in 12 patients the changes after a 4 to 8 week treatment period (mean 6.3 +/- 2 weeks; doses: 3 times 12.5 to 3 times 25 mg/day) were investigated. The following baseline variables were evaluated: the radionuclide left ventricular ejection fraction (EF) at rest and during exercise, left ventricular end-diastolic volume (EDV), regurgitant blood volume (RBV); and plasma renin activity (PRA). Repeated determinations of EF, EDV and RPA were carried out 90 minutes after application of the drug. In patients with chronic therapy, EF at rest and during exercise, EDV, RBV and PRA were reinvestigated at the end of the study. Acute administration of captopril was followed by an increase of EF (from 49 +/- 12 to 55 +/- 12%, p less than 0.001) and a slight decrease of EDV (from 389 +/- 160 to 376 +/- 146 ml, p less than 0.05). PRA significantly increased (from 1.6 to 3.1 ng/ml/h, p less than 0.05). Chronic therapy resulted in a moderate decrease of systolic and diastolic blood pressure (from 156/70 +/- 31/15 to 140/63 +/- 23/15 mm Hg, p less than 0.01). However, no significant changes were observed in EF at rest and during exercise (51 +/- 9 vs. 53 +/- 10% and 45 +/- 14 vs. 47 +/- 14%), EDV (433 +/- 179 vs. 422 +/- 179 ml) and RBV (136 +/- 81 vs. 129 +/- 77 ml). PRA was significantly increased (6.3 ng/ml/h, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Valve Insufficiency↗
PubMed1985

Combined first-pass and equilibrium radionuclide ventriculography and comparison with left ventricular/right ventricular stroke count ratio in mitral and aortic regurgitation.

Effective and total left ventricular (LV) stroke volume were assessed in 31 patients with verified aortic or mitral regurgitation, or both, and in 22 patients with normal valvular function using combined first-pass and equilibrium radionuclide ventriculography. The difference between these 2 volumes as a fraction of LV stroke volume was taken as the radionuclide regurgitant fraction. The results were compared with the LV/right ventricular (RV) stroke count ratio and with the angiographic regurgitant fraction according to the method of Sandler and Dodge. Radionuclide regurgitant fraction derived from 2 determinations with a time interval of 1 week showed good reproducibility (n = 15, r = 0.96, SEE = 9.1). Sensitivity was 100% for radionuclide regurgitant fraction and 87% for LV/RV stroke count ratio at equal specificity (100%). Radionuclide regurgitant fraction was more sensitive, especially in severely ill patients, in whom additional RV volume overload led to false-low or false-negative ratios. Angiographic and radionuclide regurgitant fraction showed linear correlation (r = 0.79, p less than 0.001). In contrast, because 5 patients had RV volume overload, only a weak correlation could be noticed between angiography and LV/RV stroke count ratio (r = 0.47, p less than 0.05). Excluding these patients, correlation substantially improved (r = 0.74, p less than 0.001). The combination of first-pass and equilibrium radionuclide ventriculography is a sensitive, specific and well reproducible method for the evaluation of mitral and aortic regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Clinical comparison of 99mTc-HMDP and 99mTc-MDP. A multicenter study.

99mTc-Hydroxymethylene diphosphonate (HMDP) was compared to 99mTc-methylene diphosphonate (MDP) with respect to image quality, lesion detectability, and the uptake ratios of normal bone to soft tissue (B/S), metastatic bone to soft tissue (M/S) and bone metastases to normal bone (M/B) at 2 and 3 h after injection in the same subjects. Thirty-three patients with bone metastases were examined in six nuclear-medicine departments, with each center using its usual bone-scanning protocol which was identical for both compounds in the same patient. The uptake of 99mTc-HMDP in normal bone (B/S) was significantly higher than that of MDP at 2 and 3 h, but there were no significant differences between the two compounds with regard to the M/S or M/B ratios. The M/B of HMDP at 2 h was not significantly different from that of MDP at 3 h, the latter showing a significantly higher B/S and M/S ratio. All lesions were detected with both compounds, even at 2 h. The image quality was rated as follows (in decreasing order): HMDP (3 h), MDP (3 h), HMDP (2 h), and MDP (2 h). HMDP was shown to be a useful bone-imaging agent, especially when shorter intervals between injection and recording are required.

Adult↗
PubMed1985

Sectoranalysis of left ventricular function by fully automated equilibrium radionuclide ventriculography.

We describe a fully automated method for quantification of left ventricular performance by equilibrium radionuclide ventriculographic studies, based on subdivision of the left ventricular region into 9 equiangular sectors. The precise identification of the left ventricular contours is achieved by the use of morphological and functional criteria in a sequential edge detection algorithm with a success rate of 96%. In addition to left ventricular global and sectorial ejection fraction the first harmonic of the corresponding Fourier spectrum is approximated to each sectorial time-activity curve and to the global one. Sectorial phase is calculated as the difference between the phase of the sectorial and global first Fourier component. Computerized comparison between the sectorial parameters at rest and during peak exercise localizes and classifies the degree of global and regional impairment in response to exercise. The processing time of 60 sec makes this method suitable for routine use. The validity of our procedure has been tested in 34 patients before and after successful transluminal coronary angioplasty. In these patients, 73% of the stenosed vessels before dilatation were localized by sectorial ejection fraction, 77% by sectorial phases, and 88% by the combination of both.

Angioplasty, Balloon↗
PubMed1985

Thallium-201 scintigraphy in the diagnosis of pheochromocytoma.

6 patients were studied by 201Tl scintigraphy; 1 of them suffered from a benign, and another from a malignant adrenal pheochromocytoma. 1 patient had a hormonal inactive adrenal tumor, 3 others multiple organ metastases of malignant pheochromocytomas. At the same time, 3 of the patients were studied by 131I-metaiodobenzylguanidine (131I-MIBG) scintigraphy. Using different techniques like kinetic studies, whole-body scan or a 201Tl-99m-Tc difference scan, benign and malignant pheochromocytoma tissues could be localized by 201Tl scintigraphy. Benign and malignant pheochromocytomas showed different kinetics of 201Tl. In 2 patients with multiple organ metastases of malignant pheochromocytomas, the metastases were partly imaged by 131I-MIBG, the others by 201Tl.

3-Iodobenzylguanidine↗
PubMed1985

[99mTc uptake and TSH receptor autoantibodies--comparative study in Basedow's disease and other thyroid diseases].

In 255 patients (normals: group I, n = 30; nontoxic goitres: group II, n = 134; toxic goitres without ophthalmopathy: group III, n = 63; Graves' disease: group IV, n = 28) a TSH-receptor-autoantibody-assay (TRAK assay) for detection of thyrotropin-binding inhibiting antibodies (TBIAb) was tested and 99mTcO4-uptake (TcTU) was measured. Normal TcTU (range: 1.5-5.5%) and normal TRAK values (normal limit: F less than 11%) were only found in group I. An increased TcTU was found in group II in 22.4% (increased TRAK values only in 2.2%). In group III an increased TcTU was measured in 34.9% of the patients (all with normal TRAK titers). The stimulation of the TSH-receptor in immunogenic hyperthyroidism by TBIAb could be demonstrated by increased TRAK values in 71.4% of the patients with Graves' disease. In correlation, TcTU was also increased in 82.1% of the patients in group IV. As the measurement of TcTU can be helpful in differential diagnosis, the functional imaging with gamma camera and computer is today a conditio sine qua non, especially in suspected hyperthyroidism.

Autoantibodies↗
PubMed1985

[Contribution of myocardial scintigraphy to control of therapy (current status and outlook)].

Pattern recognition of myocardial ischemia is initially documented in perfusion areas of critical LAD, RCA and LCX stenoses. Prerequisites of the method are mentioned. Possibilities and results of 201Tl myocardial scintigraphy are presented after coronary angioplasty and aortocoronary bypass, further considering lysis therapy of acute infarction, developments to localise infected bypasses or valves, rejection after cardiac transplantation and long-term pharmaceutical exercise-training therapy as well as therapy control of cardiac metabolism.

Angioplasty, Balloon↗
PubMed1985

[Therapy of psoriatic osteoarthropathy with EHDP].

After describing the problems involved in the therapy of psoriatic osteoarthropathy, we discuss the specific accumulation of EHDP at the site of the disease. Because of its pharmacological properties, EHDP may have a regulatory effect on the pathological changes in psoriatic osteoarthropathy. In an open experiment using 20 patients with psoriatic osteoarthropathy, we evaluated the influence of EHDP on the extent and seriousness of bone and joint disease. We carefully studied the case history, laboratory tests, and rheumatological status; in some cases, bone scintigrams were also carried out. The patients received an oral dosage of about 20 mg/kg body weight the first 2 months and about 5 mg/kg from month 3-6. Two-thirds of the patients (n = 12) indicated a decrease in joint and bone pain, and there was also detectable improvement in the bone scintigrams. Only one patient noticed a side effect from the therapy. He complained of severe itching.

Administration, Oral↗