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Biomedical subjects

G Mall

Publications and source records attributed to G Mall.

At least 163 records · Page 9Linked to original sources
PubMed1984

Determinants of survival in patients with congestive cardiomyopathy: quantitative morphologic findings and left ventricular hemodynamics.

We analyzed data from 68 consecutive patients with congestive cardiomyopathy to evaluate the prognostic significance of quantitative morphologic findings in left ventricular myocardium as compared with the prognostic significance of left ventricular hemodynamics. Left ventricular endomyocardial biopsy specimens were obtained from all patients during diagnostic heart catheterization. Myocardial fiber diameter, volume fraction of interstitial fibrosis, and intracellular volume fraction of myofibrils were determined by light-microscopic morphometry. All patients had normal coronary arteriograms, but reduced left ventricular ejection fractions. There were 23 deaths during a mean follow-up period of 1124 days. Multivariate regression analysis (Cox model) revealed that left ventricular ejection fraction (p less than .00001) and left ventricular systolic pressure (p less than .01), but not morphometric findings in biopsy specimens, were independent predictors of cardiac death. Thus, morphologic findings in the left ventricular myocardium do not contribute significantly to the prognostic evaluation in patients with congestive cardiomyopathy studied by hemodynamic and angiographic methods.

Adult↗
PubMed1984

[Significance of morphological findings in congestive cardiomyopathy].

In 48 consecutive patients with myocardial disease, left ventricular biopsies were taken during diagnostic heart catheterization. Morphometric quantification of ultrastructural alterations of the heart muscle was performed. The patients were subdivided into 3 groups by means of clinical criteria: Group A: 18 surviving patients with pathological ECG, normal left ventricular ejection fraction, and normal coronary arteries. The mean follow-up in this group was 22 months. Group B: 23 surviving patients with congestive cardiomyopathy, i.e., normal coronary arteries and depressed left ventricular ejection fraction. The mean follow-up in this group was 23 months. Group C: 7 patients with congestive cardiomyopathy, who died during the study period from cardiac complications. The mean survival time of these patients after heart catheterization was 23 months. Myocardial fiber diameter, volume fraction of interstitial fibrosis, intracellular volume fraction of myofibrils, and the total myofibrillar mass per 100 g heart muscle were determined by light microscopic morphometry. In a pilot study comprising 26 patients the reproducibility of the morphological results were assessed by investigation of two different biopsy specimens taken from different areas of the left ventricular wall of each patient. The study revealed a coefficient of variation of 6% for myocardial fiber diameter, 28% for myocardial fibrosis, and 4% for myofibrillar volume fraction. Since there are only poor results from morphological investigations of the diseased myocardium, it was the purpose of the follow-up study presented in this paper: To quantify ultrastructural alterations of the heart in congestive cardiomyopathy by morphometric techniques. To correlate the quantitative morphometric data with the contractile state of the left ventricle.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1983

Coronary dilatory capacity in idiopathic dilated cardiomyopathy: analysis of 16 patients.

Hemodynamic function and overall coronary blood flow (argon technique) were measured in 16 patients with idiopathic dilated cardiomyopathy (IDC) and in 12 patients without detectable heart disease (control subjects) referred for precordial pain. In patients with IDC, coronary blood flow was normal at rest (78 +/- 17 ml/100 g-min versus 78 +/- 9 in control subjects). During maximal inducible coronary vasodilation (dipyridamole, 0.5 mg/kg), coronary blood flow was significantly reduced (142 +/- 38 ml/100 g.min versus 301 +/- 64 in control subjects; p less than 0.001). Consequently, obtainable minimal coronary resistance was increased in IDC (0.54 +/- 0.20 mm Hg/ml/100 g.min versus 0.23 +/- 0.04 in control subjects; p less than 0.001). In patients with IDC, left ventricular (LV) end-diastolic pressure was significantly increased (19 +/- 11 mm Hg versus 6 +/- 3 in control subjects; p less than 0.005), and the LV ejection fraction was diminished (36 +/- 11% versus 72 +/- 3% in control subjects; p less than 0.001). In patients with IDC, LV end-diastolic pressure correlated significantly with the obtained minimal coronary resistance after application of dipyridamole (r = 0.85; p less than 0.001). LV catheter biopsy specimens revealed no alterations in myocardial microvasculature. Thus, coronary dilatory capacity is impaired in patients with IDC, due partially to an increase in extravascular component of coronary resistance.

Adult↗
PubMed1983

Quantitative morphologic findings of the myocardium in idiopathic dilated cardiomyopathy.

This study assesses the relation between quantitative morphologic findings and left ventricular contractile function in patients with idiopathic dilated cardiomyopathy. Left ventricular endomyocardial catheter biopsy specimens were obtained from 73 patients during diagnostic heart catheterization. All patients had normal coronary arteriograms but abnormal electrocardiograms. Twenty-six patients had normal left ventricular function (ejection fraction greater than or equal to 55%), whereas 47 patients had contractile dysfunction (ejection fraction less than or equal to 54%). Myocardial fiber diameter, volume fraction of interstitial fibrosis, and intracellular volume fraction of myofibrils were determined by light microscopic morphometry. Results of light microscopic morphometry were confirmed by electron microscopic morphometry in 12 patients. The coefficient of variation (analysis of several biopsies from the same patient) was 6% for determination of fiber diameter, 43% for interstitial fibrosis, and 3% for volume fraction of myofibrils. Fiber diameter (r = -0.32, p less than 0.01) and fibrosis (r = -0.47, p less than 0.001) showed a negative correlation, the volume fraction of myofibrils (r = 0.55, p less than 0.001) and calculated myofibrillar mass per 100 g of myocardium (r = 0.64, p less than 0.001) a positive correlation with the ejection fraction. Thus, (1) sampling error is low for determination of fiber diameter and myofibrils but high for evaluation of fibrosis, and (2) a reduction in the volume fraction of myofibrils and an increase in fibrosis are morphologic correlates of left ventricular dysfunction in patients with idiopathic dilated cardiomyopathy.

Adult↗
PubMed1983

Dipyridamole-induced capillary endothelial cell proliferation in the rat heart--a morphometric investigation.

20 male Wistar rats were randomly divided into two equal groups. Each experimental rat was injected with 4 mg . kg-1 dipyridamole ip twice daily for 4 weeks, the control rats received sham injections of an equal volume of saline. The rats were fixed by retrograde vascular perfusion. Left ventricular papillary muscles were sampled for light and electron microscopic morphometry. By means of a combination of serial section reconstruction and morphometry we could demonstrate that the number of capillary endothelial cell nuclei per tissue volume had increased by 37% (P less than 0.01), whereas the average nuclear volume remained constant. All other morphometric parameters (volume densities of myocardial cells, capillaries, cellular and non-cellular interstitial tissue, and myocardial cell nuclei; surface area, diameter, and density of capillaries; volume densities of myofibrils, mitochondria, and sarcoplasmic matrix; surface areas of the inner and outer mitochondrial membranes; dimensions of average mitochondrial section profiles) were unchanged. We conclude that chronic dipyridamole application induces proliferation of capillary endothelial cells in the rat myocardium, possibly by an increase of myocardial blood flow.

Animals↗
PubMed1982

Mesangial alterations in steroid-responsive minimal change nephrotic syndrome.

Renal biopsies from 25 children with steroid-sensitive minimal change nephrotic syndrome were evaluated retrospectively to determine whether there is any relation between the morphological changes and the frequency of relapses. Biopsy material was examined by light-, immunofluorescence-, and electron microscopy, and by morphometric methods. The patients were divided in a group of 15 children with frequent relapses (FR) and another group of 10 children with an absence of, or only infrequent, relapses (NR/IR). Semiquantitative evaluation of biopsy specimens disclosed no significant differences between groups, but morphometric measurements performed on toluidine stained semi-thin sections showed a significant increase of mesangial nuclei in FR compared with NR/IR (P less than 0.01). Furthermore, the mean area of mesangial nuclei was decreased and the relative frequency of smaller nuclear profiles was higher in patients with FR compared to NR/IR (p less than 0.01). These findings suggest mesangial cell activation in FR which may be related to a longer course of the disease prior to renal biopsy (mean 4.0 years in FR vs. 1.4 years in NR/IR). In our opinion, morphometric assessment of discrete mesangial alterations is a promising method for exploring clinicopathological correlations in minimal change nephrotic syndrome.

Adolescent↗
PubMed1982

[Experimental Klebsiella pneumonia (author's transl)].

Experimental pneumonia was investigated by light microscopic, electron microscopic and morphometric methods in mice infected with the problem spore Klebsiella pneumoniae. In the early stage (2 to 7 hours post infection) we found Klebsiellae and aggregates of platelets in the pulmonary capillaries, but we could not establish significant structural alterations with morphometric methods. The ultrastructural investigation revealed alterations of the alveolar lining cells and the endothelial cells of capillaries and an infiltration of the interalveolar septula with polymorphonuclear and mononuclear leucocytes. These early changes were followed by an intraalveolar infiltration with inflammatory cells. Complement activation is considered as a trigger of the initial inflammatory reaction. The results of our study indicate that bacterial pneumonia starts in the interalveolar septula and secondary involves the alveolar spaces. A restitutio ad integrum of the lung develops 11 days post infection.

Animals↗
PubMed1982

Procollagen-type III-peptide serum concentrations in chronic persistent and chronic active hepatitis and in cirrhosis of the liver and their diagnostic value.

Until now the determination of fibrotic processes in liver disease was restricted to histological examination of liver tissue. Recently a RIA was developed to determine the procollagen-type III-peptide concentrations in biological fluids. We used this RIA to measure the serum procollagen-type III-peptide concentrations in patients with chronic liver disease. Additionally in 24 patients with chronic persistent and chronic active hepatitis the collagen content in liver biopsies was determined histomorphometrically. The serum procollagen-type III-peptide concentrations in healthy controls (n = 40) were 6.4 +/- 0.6 ng/ml, in chronic persistent hepatitis (n = 47) 8.7 +/- 0.5 ng/ml, in chronic active hepatitis (n = 53) 20.8 +/- 2.9 ng/ml, and in alcoholic cirrhosis of the liver (n = 22) 47.7 +/- 6.1 ng/ml. Thus the patients with chronic active hepatitis and cirrhosis of the liver showed significantly elevated serum procollagen-type III-peptide levels. In chronic hepatitis a highly significant correlation (p less than 0.001) could be demonstrated between collagen content in liver tissue and serum procollagen-type III-peptide concentrations. The determination of serum procollagen-type III-peptide concentrations may prove a new useful parameter in biochemical evaluation of liver disease.

Biopsy↗
PubMed1981

[Angina pectoris syndrome in patients with normal coronary arteriograms (X syndrome) (author's transl)].

In 37 patients with typical exercise-dependent angina pectoris but with normal coronary arteriograms and normal left ventricular function at rest (X syndrome), the dipyridamole-induced dilatory reserve of the coronary vascular system was reduced significantly to about 50% of control values (P less than 0.001). There were no changes in the small vessels causing the reduced dilatory reserve, but ultrastructural changes in the mitochondria were demonstrable. In the patients with X syndrome there was a significant reduction of lactate extraction (P less than 0.05) after electrical atrial stimulation (150/min) and in most cases lactate production was demonstrable. In the control group the myocardial lactate uptake was unchanged. Left ventricular function in patients with X syndrome was normal at rest whereas during exercise it was significantly reduced (P less than 0.001). These results show that X syndrome consists of a particular form of ischaemic heart disease with still normal left ventricular function at rest, but disordered pump activity during physical stress.

Adult↗
PubMed1981

Impaired maturation of Purkinje cells in the fetal alcohol syndrome of the rat. Light and electron microscopic investigations.

Alcohol was administered in a vitamin-supplemented liquid diet (Stardit) to Wistar rats 4 weeks before mating and during pregnancy. Of the daily calories 38--40% were supplied by alcohol and by isocaloric sucrose in the controls. Offspring of alcohol drinking dams showed a reduced birth weight and gained weight less rapidly than the controls. On day 3, 4, 7, 12, 17 and 21, experimental animals and controls were perfused for histological and electron microscopic investigations. Morphometric analysis of the cerebella (Fol. 5 and Fol. 8) showed no difference in the number of Purkinje cells. However, on day 7 the Purkinje cell nuclei of experimental pups were significantly smaller. This difference disappeared at day 12. Electron microscopic investigations in the 4, 7, and 12 days old experimental animals revealed a delayed cytoplasmic maturation of Purkinje cells which mainly involved the rough endoplasmic reticulum. At 17 days, there was no difference between the two groups. These data are discussed in relation to alcohol-induced metabolic changes in the brain.

Animals↗
PubMed1981

Reduced coronary dilatory capacity and ultrastructural changes of the myocardium in patients with angina pectoris but normal coronary arteriograms.

Hemodynamic and metabolic studies were performed in 15 patients without heart disease (controls, group A), in 21 patients with typical stress-induced anginal pain but normal coronary and left ventricular angiograms (angina pectoris with normal arteriogram, group B), and in 10 patients with angiographically proved coronary artery disease (CAD, group C). Coronary dilatory capacity, determined by measuring total myocardial blood flow at rest and during maximal coronary vasodilatation (dipyridamole, 0.5 mg/kg i.v.), was markedly reduced in group B and C patients. In group B patients, left ventricular catheter biopsy specimens revealed no evidence of small-vessel disease, but did show histologic alterations of mitochondria. During atrial pacing, the control subjects showed no changes in myocardial lactate uptake, whereas in group B patients, myocardial lactate production occurred. In contrast to controls, patients in group B showed a significant decline in ejection fraction and circumferential fiber shortening during isometric exercise. These findings suggest that myocardial ischemia is the cause of angina pectoris in patients who have angina but normal coronary arteriograms.

Adult↗