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Biomedical subjects

M Stauch

Publications and source records attributed to M Stauch.

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

[Use of digital subtraction angiography in localizing an anomalous pulmonary vein return in a case of congenital shunt disease].

The exact analysis of an anomalous pulmonary venous return in patients with congenital shunt disease can lead to some difficulties when using the standard catheterization techniques. A left-sided anomalous pulmonary vein was suspected in a case with atrial and ventricular septal defects, but could not be evaluated during the catheterization procedure. The pathological vessel could be demonstrated exactly only by venous digital subtraction angiography. Thus, the digital subtraction angiography showed a diagnostic benefit in this complex shunt disease and should be considered in further problematic cases.

Adult↗
PubMed1987

[Noninvasive assessment of the severity of obstruction in hypertrophic obstructive cardiomyopathy (HOCM) in bidirectional Doppler sonography of the common carotid artery. Simultaneous comparison with invasive measurements].

A series of 6 patients with HOCM underwent pre- and poststenotic left ventricular pressure measurements with simultaneous monitoring of the Doppler velocity in the right common carotid artery. Baseline measurements were followed by interventions. Mean pressure gradient was 37 +/- 17 mm Hg at baseline, during Valsalva test 61 +/- 19 mm Hg, postextrasystolic 86 +/- 36 mm Hg, after 0.8 mg NTG 104 +/- 57 mm Hg. Midsystolic velocity decreased when the pressure gradient increased. These data suggest that changes in the carotid artery Doppler velocity correspond to alterations in the pressure gradient. Midsystolic retrograde flow was found in 5 out of 6 patients with pressure gradients exceeding 80 mm Hg. Abnormalities in midsystolic flow were never observed in control subjects. We conclude that carotid Doppler sonography is a useful adjunct to the non-invasive evaluation of patients with HOCM.

Adult↗
PubMed1987

Effect of right ventricular hypertrophy on cardiac performance and the relation between right ventricular systolic peak pressure and end-systolic volume.

To investigate the role of hypertrophy of the right ventricle upon right heart performance and the significance of the peak systolic pressure/end-systolic volume (P/V) ratio in terms of right ventricular systolic performance, simultaneous measurements of radionuclide ventriculograms and central hemodynamics were done in 32 patients with chronic obstructive pulmonary disease. In 26 of the patients (80%) technically adequate two-dimensional echocardiograms could be performed. In the subset of patients with increased (greater than or equal to 6 mm) right ventricular end-diastolic wall thickness no relationship between pulmonary artery pressure and right ventricular ejection fraction (RVEF) existed in comparison with the remaining patients. P/V indices and cardiac output were not decreased. Considering the patients, whose P/V ratio did not increase from rest to exercise, RVEF decreased highly significantly more than in the remaining patients. The ratio of wall thickness and end-diastolic radius as determinant of peak systolic stress was significantly decreased in these patients compared with the remaining patients. In the patients with right ventricular hypertrophy despite significantly higher values of pulmonary artery pressures and resistances, the afterload in terms of systolic wall stress is markedly reduced. We conclude that in the hypertrophic state, right ventricular performance is not impaired despite decreased RVEF values. In the patients whose P/V ratio does not increase from rest to exercise, an inappropriate high peak systolic wall stress may exist both due to inadequate wall thickness and increased diameter of the right ventricle. The role of P/V in terms of prognosis and development of decompensated right heart failure remains undetermined.

Biomechanical Phenomena↗
PubMed1987

[Hemodynamic effects of a new calcium antagonist, bepridil, in patients with coronary artery disease].

Hemodynamic Effects of the New Calcium Antagonist Bepridil in Patients with Coronary Artery Disease. For the evaluation of the hemodynamic effects of the new calcium antagonist bepridil 11 patients with coronary artery disease were studied. The following parameters were measured before, immediately after and 20 min after injection of 3 mg/kg bepridil i.v.: pulmonary capillary wedge pressure, pulmonary artery pressure, cardiac output, mean aortic pressure, peripheral vascular resistance, prolongation of the QT-interval in the ECG. Bepridil led acutely to a slight deterioration of the left ventricular function with a significant increase of the preload, but this negative effect was neutralized by the concomitant decrease of the afterload. These results indicate a favorable hemodynamic profile of this new agent.

Bepridil↗
PubMed1987

[Radionuclide ventriculography--a noninvasive method of diagnosis and quantification of tricuspid valve insufficiency].

The diagnosis of tricuspid regurgitation (TR) is difficult to make by simple clinical methods or by invasive techniques. Contrast echocardiography and Doppler echocardiography have improved diagnostic results, but a golden standard is still not available. Radionuclide ventriculography (RNV) is a well-established method for the detection and quantification of a volume load on the left ventricle: the regurgitation fraction can simply be derived from the regurgitant index as the ratio of enddiastolic-endsystolic count-rate differences between the left and right ventricle. In left heart valvular regurgitation a regurgitant index exceeding the upper normal limit can be expected. This study was performed to evaluate the diagnostic accuracy of an abnormally low regurgitant index in detecting TR, which is accompanied by an isolated volume load on the right ventricle. A series of 33 patients with TR on physical examination and cardiac catheterization underwent RNV and was compared with 48 patients with right ventricular enlargement or pressure load on the right ventricle. In addition, the specificity of the method was evaluated in 470 consecutive patients with various forms of heart disease. In 18 out of 20 subjects with isolated TR a regurgitant index below the lower normal limit was found. The remaining 2 cases with minor TR had a regurgitant index within the normal range, which is 0.89 to 1.97 in this laboratory. In patients with additional volume load on the left ventricle, the sensitivity of the method was found to be low, as could be expected from the principle of the method. The time-activity curve over the liver was usually in phase with that recorded over the atria in subjects with TR. Therefore, the additional examination of a region of interest over the liver was particularly useful in these patients with concomitant aortic or mitral valve regurgitation. None of the 48 patients with right ventricular enlargement or pressure load on the right ventricle had a falsely positive result. A total of 17 out of 470 consecutive patients had a regurgitant index below the normal range; left ventricular function was severely impaired in 9 of these patients. The remaining subjects had a regurgitant index slightly below the lower normal limit. In conclusion, RNV has a high sensitivity in the diagnosis of TR in patients without left heart valvular regurgitation and a high specificity in patients without severely impaired left ventricular function and without left-to-right shunt through an atrial septal defect.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1986

Left heart function in chronic obstructive lung disease.

In patients with varying degrees of chronic obstructive pulmonary disease (COPD), simultaneous measurements of central hemodynamics and left ventricular radionuclide ventriculograms at rest and during exercise were made. In 21 of these patients, satisfactory echocardiograms could be performed. In seven of the patients, arterial blood pressure at rest was increased. Decreased compliance of the left ventricle was thought to be present in patients with COPD and additional arterial hypertension. The left ventricular ejection fraction (LVEF) at rest was in the high normal range in all patients. During exercise, no further increase was observed. This pattern of LVEF response seems to be typical in patients with COPD. Because the highest values were observed in the more severe COPD and right ventricular hypertrophy, it is unlikely that an impairment of left ventricular function is caused by COPD. In five of 27 patients, an abnormal decrease of LVEF and regional hypokinesis occurred during exercise, thus suggesting additional coronary heart disease. The fact that at least 30% of the patients with COPD suffered from arterial hypertension and 20% of the patients exhibited unexpected ischemia detected by regional hypokinesis in RNV during exercise, but not in the ECG, may be of practical relevance. Coronary angiography was not indicated because most of these patients were over 65 and the factor limiting the working capacity was ventilatory impairment and not angina pectoris, in all patients. For this reason, a diagnostic uncertainty remains with regard to additional coronary heart disease in the older patients with advanced chronic obstructive pulmonary disease.

Aged↗
PubMed1986

Haemodynamic response to exercise in patients with chest pain and normal coronary angiograms.

A series of 42 patients with chest pain but normal coronary angiograms and normal haemodynamics at rest were prospectively classified as typical angina (group 1, N = 9) or atypical angina (group 2, N = 16) or non-anginal chest pain (group 3, N = 17). All patients underwent radionuclide ventriculography and measurement of pulmonary artery pressure at rest and during maximum exercise. Comparison of data during exercise revealed significantly higher (P less than 0.025) left ventricular filing pressures as reflected by the diastolic pulmonary artery pressure in group 1 (29 +/- 5 mmHg) than in both group 2 (22 +/- 6 mmHg) and group 3 (22 +/- 5 mmHg). The rest-to-exercise change in left ventricular ejection fraction was variable and not significant in group 1 (62 +/- 6% vs 63 +/- 14%). By contrast, both group 2 and group 3 had significant increases (63 +/- 6% vs 69 +/- 10%, P less than 0.02 and 63 +/- 5% vs 68 +/- 5%, P less than 0.01). The classification as 'typical angina' was predictive of an abnormal (greater than 25 mmHg) filling-pressure response to stress. The positive and negative predictive values were 78% and 70%, respectively. The clinical classification was not a predictor of an abnormal (delta less than 5%) ejection-fraction response. No correlation between radionuclide and filling-pressure data could be established. The data suggest that the majority of patients assigned to group 1 manifested an impaired left ventricular function with exercise. This was primarily related to abnormalities in diastolic filling while the systolic performance was not consistently depressed.

Adult↗
PubMed1986

Pulmonary gas exchange and central hemodynamics at rest and during exercise in patients with chronic obstructive pulmonary disease.

Right-heart catheterization and ergometry with arterial and mixed venous blood gas analysis were performed in 27 patients with a wide range of chronic obstructive pulmonary diseases. The purpose of the examination was to evaluate the risk in patients for lung surgery or to detect additional heart diseases. Patients who developed exertional hypoxia (group 1) were compared with others who did not (group 2). In all patients the steady-state maximal workload was determined by ventilatory dysfunction. Both groups had normal values for mixed venous pO2 and normal increase of the circulatory parameters during exercise. The patients with exertional hypoxia differed from the others in that they showed no decrease of venous admixture and alveolar-arterial oxygen gradient. In addition, these patients had increasing pCO2 values at rest compared with exercise, indicating alveolar hypoventilation and ventilation-perfusion mismatching. Because of the good correlation of the absolute values of FEV1 (forced expiratory volume in 1 s) with pulmonary artery pressures, parameters of gas exchange and working capacity, this lung function parameter seems to have a central role in predicting the functional state of patients with chronic obstructive disease. Ergometry and blood gas analysis should be performed in addition because these values cannot be predicted with the calculated postoperative FEV1.

Aged↗
PubMed1986

Interactions of vasodilators with calcium entry- and beta-blockers in patients with coronary heart disease.

Combinations of antianginal drugs may be used for an additive effect against angina, but also to off-set unwanted effects of one drug with another, either by direct effects or by a reduction of dosage of each drug. Based on earlier studies with separate drugs we have now examined the effect of 150 mg bupranolol combined with 40 mg isosorbide dinitrate (ISDN) in one retarded tablet, given twice daily. 22 patients with CHD entered the study, 11 of those with and 11 without signs of ischemia during exercise. In an acute radionuclide ventriculographic (RNV) study 2 h after the tablet, ejection fraction (EF) during exercise increased only in patients with exercise ischemia (+6%, p less than 0.001). In the other patients EF did not change. After 21 days of treatment echocardiographically determined end-systolic and end-diastolic diameters decreased, resulting in an increase of shortening fraction by 15.6% (p less than 0.05). Heart rate, systolic and diastolic pressure and ST-segment depression decreased significantly. In another acute RNV study the effect of a venous vasodilator, molsidomine 4 mg s.l., was examined after nifedipine 10 mg s.l. in 19 patients with CHD, 9 with and 10 without exercise ischemia. Differences between drugs were most prominent during exercise. In the nonischemic group EF rose by 6.6% after nifedipine (n.s.) and by 14% after molsidomine (p less than 0.01 against control). In the group with ischemia EF rose by 12.6% after nifedipine and by 17.4% after additional molsidomine, significant against control (p less than 0.01) as well as against nifedipine (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Bupranolol↗
PubMed1986

Parametric imaging of experimentally simulated Wolff-Parkinson-White syndrome conduction abnormalities in dogs: a concise communication.

In order to test the diagnostic potential of phase analysis of radionuclide ventriculography (RNV) for localizing accessory bundles in Wolff-Parkinson-White (WPW) syndrome, 24 experimental runs were performed in three open chest instrumented dogs. After a baseline study, WPW syndrome was simulated by stimulation at seven different sites around the base of the ventricles, and RNV's were obtained. Subsequent data processing including Fourier transformation allowed the localization of the site of the first inward motion of the ventricles by an isophasic wave display. In sinus rhythm, the septum contracted first. During ectopic premature ventricular stimulation by triggering the atrial signal, the phase scan was altered only when the stimulus was applied earlier than 20 ms before the expected QRS complex during sinus rhythm. During stimulation with fixed frequency, only the left lateral positions of the premature stimulation were detected by phase analysis with a sensitivity of 86%. Neither the antero- or posteroseptal nor the right ventricular premature contraction pattern could be exactly localized.

Animals↗
PubMed1986

[Comparison of left ventricular end-diastolic volume determined by radionuclide ventriculography, by contrast-media ventriculography and by a geometry-independent method].

Ejection fraction and end-diastolic volume (EDV) are valuable parameters of left ventricular function. They can be measured by radionuclide ventriculography. This study examines EDV in comparison to two other methods. A comparison was made between EDV derived from radionuclide ventriculography (RNV), standard contrast ventriculography and a 'hybrid' method, which calculates EDV from ejection fraction, heart rate and thermodilution cardiac output. Two groups of patients were examined: 54 patients with various cardiac diseases by contrast and radionuclide ventriculography (RNV); and 18 patients with typical angina were examined by RNV at rest and during exercise three times: Control without medication, 20 minutes after 10 mg metoprolol i.v. and again 10 minutes after the second exercise and 10 mg isosorbide dinitrate sublingually. In comparison to contrast ventriculography RNV overestimated EDV by 27%, and in comparison to the hybrid method by 11% with satisfactory linearity. The extent of error increases with decrease of ventricular volume. The assumption that the two short axes of the left ventricle are equally long causes one quarter of total error. Errors caused by the algorithm delineating the borders of the left ventricle cannot be measured. For clinical purposes radionuclide ventricular EDV seems to yield satisfactory results.

Cineangiography↗
PubMed1986

Specification of regional wall motion abnormalities by phase analysis of radionuclide angiograms in coronary artery disease and non-coronary artery disease patients.

Fourier transform of gated radionuclide ventriculograms (RNV) permits the quantitative evaluation of regional wall motion abnormalities (RWMA) regarding both regional magnitude (amplitude display) and regional time sequence of contraction (phase display). In this study, an attempt was made to further specify coronary artery disease (CAD) and non-CAD RWMA detected on consecutive exercise RNV in 17 patients (pts) with proven severe CAD; or on resting RNV in 24 pts with transmural myocardial infarction (MI) compared with 27 pts after treatment with daunorubicin (DAU). RWMA were defined objectively from parametric images by a decrease of the sectorial amplitude by more than 2 s.d.s of normal as determined by quantification of RNV studies of 20 normal individuals. In 15 out of 17 CAD pts (88%) and in 19 out of 24 MI pts (79%), a significantly decreased regional amplitude was found. Importantly, in all abnormal CAD and MI amplitude scans (100%), a significantly abnormal phase delay in the same region could be noted. In five out of 27 pts on DAU (18%) an apical hypokinesis could be verified. In comparison with CAD pts, however, the phase distribution was normal in all these DAU pts. Thus, standardized phase analysis of RNV data provides a powerful tool for specifying RWMA. It allows a highly specific separation of RWMA caused by exercise-induced ischemia, MI, or DAU.

Adult↗
PubMed1985

Effects of molsidomine on regional contraction and global function of the left ventricle.

Fifteen consecutive patients (mean age 54 years) with proven coronary heart disease were studied with radionuclide ventriculography. After resting and exercise control studies, repeat studies were performed after administration of 4 mg of molsidomine sublingually and again after administration of 10 mg of metoprolol intravenously. Rest to exercise ejection fraction (EF) decreased significantly. This was significantly attenuated by molsidomine and by metoprolol. In a subset of nine patients with exercise ischemia, EF showed significant (p less than 0.05) improvement after molsidomine administration (46.7 +/- 13.7% to 57.1 +/- 16.7%), which was diminished to 54.4 +/- 10.5% after metoprolol administration. In the subgroup without exercise ischemia, molsidomine increased the EF to a lesser extent (47.3 +/- 12.7% to 52.6 +/- 13.4%, p less than 0.05). After administration of metoprolol the EF decreased below the control level (44.4 +/- 10.6%). Regional Fourier amplitudes accentuated the differences between the two groups. We conclude that molsidomine and metoprolol improve left ventricular function in patients with coronary heart disease and ischemia during exercise. In patients with reduced left ventricular function without signs of ischemia, molsidomine improves function as well and should be used additionally, if beta blockers are indicated for other reasons.

Adult↗
PubMed1985

Limitations of radionuclide ventriculography in the non-invasive diagnosis of coronary artery disease. A correlation with right heart haemodynamic values during exercise.

A consecutive series of 56 patients with chest pain but no evidence of previous myocardial infarction was prospectively studied by radionuclide ventriculography to determine the value of global and regional radionuclide indices in detecting coronary artery disease. The results were correlated with the clinical judgment of chest pain, the results of the exercise electrocardiogram, and the right heart haemodynamic measurements during exercise. As a result of the criteria for entry, the study group was representative of the population seen in such a clinical setting. Only 25% of patients had coronary artery disease. The predictive power of radionuclide ventriculography was limited. The conventionally used criterion that normal subjects have an increase in left ventricular ejection fraction of at least 5% with exercise provided only 78% sensitivity and 57% specificity. Fourier analysis and visual interpretation of radionuclide studies wrongly diagnosed three out of 10 patients with extensive disease requiring surgery. These results suggest that radionuclide ventriculography is of limited value in the non-invasive diagnosis of coronary artery disease.

Adult↗