Influence of nonhemodynamic factors on the microcirculation in moderate arterial essential hypertension

This study is aimed at examining the role of non-hemodynamic factors on the impaired microcirculation in patients with moderate essential hypertension. In a series of 31 patients (mean age, 47.8 +/- 1.1 years) with newly diagnosed untreated moderate essential hypertension (mean systolic blood pressure 161.7 +/- 2.0 mm Hg, mean diastolic blood pressure 102.4 +/- 1.5 mm Hg), parameters of the capillaroscopic examination of the finger microcirculation (mean number of capillaries, NRCAP), length of the capillaries (LECAP, microns), diameter micron) of the efferent (EFDI) and afferent (AFDI) apillaries, and mean red blood cell velocity (RBCV, microns/sec), which was measured by the flying spot technique, were correlated with a number of hormones (sampled after an overnight fast) including: plasma renin activity, aldosterone, and parathyroid hormone (PTH). A significant correlation (P less than .05) could be obtained between several parameters of the microcirculation and PTH:PTH (23.8 +/- 1.4 pg/mL)-NRCAP (14.9 +/- 0.5): r = -0.440, P = .013; PTH-AFDI (4.0 +/- 0.5 microns): r = 0.442, P = .012; PTH-EFDI (2.8 +/- 0.5 microns): r = 0.416, P = .019; PTH-RBCV (711 +/- 69 microns/sec): r = -0.351, P = .05. Furthermore, 24-h urinary norepinephrine (U-NOR) and afferent and efferent diameter of the capillaries intercorrelated significantly: U-NOR (46.0 +/- 6.2 micrograms/24 h)-AFDI: r = 0.439, P = .034; U-NOR-EFDI; r = 0.462, P = .025. This study shows that in patients with moderate essential arterial hypertension nonhemodynamic factors have an influence at the level of the microcirculation.

Quantitative turbidimetric assay for determining myoglobin evaluated

A recently introduced turbidimetric immunoassay using shell/core particles for determination of myoglobin (Turbiquant Myoglobin, Behringwerke, Marburg, Germany) was evaluated on the Behring Turbitimer analyzer. Intra-assay CV varied between 1.0% and 3.2%; interassay CV was between 2.0% and 3.6%. Linear results were obtained between 2.8 nmol/L and 36.7 nmol/L. Manual dilution in saline solution allowed measurement of myoglobin concentrations up to 25,400 nmol/L. In the tested range, no high-dose 'hook' effect was observed. Haemolysis interfered with the assay when haemoglobin concentrations exceeded 2 g/L. The occurrence of error codes due to the presence of triglycerides was shown to depend on particle size. Repeat assays on diluted samples were necessary at triglyceride concentrations of 2.3 mmol/L for post-prandial chylomicrons (200-1000 nm), and at 11-31 mmol/L for very-low density lipoprotein-triglycerides (80-200 nm). No significant interferences of haptoglobin, bilirubin, iodine containing contrast media, and rheumatoid factors were detected for the assay. Treatment of lipaemic samples with Lipoclean (Behringwerke) resulted in lower myoglobin values. Simultaneously drawn serum and heparin-plasma samples gave comparable myoglobin results. However, values obtained in EDTA- or citrate-treated plasma samples occasionally differed significantly from serum values. The upper reference limit for myoglobin concentration was 4.2 nmol/L. The turbidimetric assay correlated well with a radioimmunoassay (Byk-Sangtec; r = 0.892) and with the automated nephelometric assay (Behringwerke; r = 0.944). Values obtained by turbidimetry were comparable to those obtained by the latex agglutination test (Behringwerke).

Humoral immune response against contractile proteins (actin and myosin) during cardiovascular disease

Sensitive and highly specific ELISA assays were developed to determine humoral immune response against actin and myosin in 122 patients suffering from various cardiovascular diseases: acute viral myocarditis (n = 10, MYO), acute myocardial infarction (n = 28, AMI), valve surgery (n = 35, VALVE), coronary bypass surgery (n = 35, CABG), and peripheral vascular surgery (n = 14, VASC). Anti-actin and anti-myosin antibodies were determined on admission and serially during a period of 90 days. Anti-actin and anti-myosin immune response (IgG, IgM) was expressed comparing absorbance of the patients' serum with a reference serum. In the different patient groups significantly (P less than 0.01) higher anti-actin and anti-myosin antibody concentrations were found on admission compared with age-matched control groups. During follow-up, all patient groups except the vascular surgery group showed a significant immune response against actin and myosin, with an immune response ratio (peak/admission) for AMA IgG and IgM respectively of 2.12 and 2.40 in the VALVE group, 1.30 and 1.99 in the CABG group, 1.42 and 1.48 in the AMI group and 1.66 and 1.25 in the MYO group; and for AAA IgG and IgM respectively of 1.57 and 3.00 in the VALVE group, 1.54 and 1.64 in the CABG group, 1.25 and 1.07 in the AMI group, and 1.42 and 1.42 in the MYO group. A significant correlation between pre-cardiac injury and peak post-cardiac injury anti-myosin and anti-actin autoantibody levels could be demonstrated suggesting that pre-injury sensitization to these antigens plays an important role in evoking post-cardiac injury immune response.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of the fibrinolytic response to desmopressin acetate (DDAVP) infusion versus venous occlusion in patients with coronary artery disease

A 20-min venous occlusion and a desmopressin acetate (DDAVP, 0.4 microgram.Kg-1, 15 min) infusion test have been compared to evaluate fibrinolytic capacity in proven coronary artery disease. Basal values of plasma tissue plasminogen activator (t-PA) activity and antigen and of t-PA inhibitor (PAI) were normally distributed in this patient group. However, after both stimuli, highly significant (P less than 0.005) increases of t-PA antigen and activity have been observed. Renormalization of t-PA levels after DDAVP infusion occurred more rapidly for antigen (120 min) than for activity concentrations (greater than 240 min). A DDAVP infusion test seems more appropriate for evaluation of the fibrinolytic capacity as the induced decrease in PAI level was significant (P less than 0.005) and lasted for at least 240 min, while it was not significant for the venous occlusion test.

Effects of isradipine on peripheral hemodynamic reflex responses in mild-to-moderate essential hypertension

In a randomized double-blind, placebo-controlled, crossover study of isradipine (5 mg twice daily), effects on peripheral hemodynamic reflex responses were studied in nine patients (mean age 48 years) at baseline and after six weeks of active treatment. Assessments included vital signs, resting blood flow in the calf and finger (using an electrocardiograph-triggered venous occlusion plethysmograph), reflex responses during isometric exercise and cold pressor resistance, and venous capacitance in the forearm and calf. Isradipine lowered systolic and diastolic blood pressure as well as mean arterial pressure in patients with mild-to-moderate essential hypertension without reflex tachycardia or venoconstriction. All of the reflex responses studied were attenuated. It is concluded that vasodilatation of the peripheral circulation induced by isradipine contributes partially to the blood pressure-lowering effect.

Diagnostic approach to patients with primary hyperaldosteronism

We report the case of a 38-year-old patient with primary hyperaldosteronism. The diagnosis was made by the demonstration of a non-suppressible high aldosterone level in association with a hypokalemia, an inappropriate kaliuresis and low plasma renin activity. As the choice of the therapeutic approach is dictated by the subtype, further investigation was needed. Using a number of hormonal studies and noninvasive imaging techniques, we could establish the diagnosis of adrenocortical adenoma. Histological examination confirmed our diagnosis. We further discuss briefly the characteristics of the four subtypes of primary hyperaldosteronism and show that the used biochemical markers and imaging techniques are able to differentiate them.

Transesophageal echocardiography for insertion of a physiological pacemaker in early pregnancy

A dual chamber pacemaker was implanted during the first trimester of pregnancy in a patient with second-degree heart block and syncope. Transesophageal echocardiography was used to confirm satisfactory position in the right atrial appendage.

Plasma and erythrocyte lipids in two families with heterozygous hypobetalipoproteinemia

Erythrocyte morphology, kinematic viscosity, and membrane lipid composition have not been well documented in heterozygous hypobetalipoproteinemia (HBL). In our study of nine subjects with HBL from two kindreds, three presented with schistocytes (3-6%) while two of them also showed acanthocytosis (25-35%) on their peripheral blood films. The other affected family members had a normal RBC morphology despite a decreased kinematic viscosity of RBC suspension at 37 degrees C (log eta = 0.20 +/- 0.02 vs. log eta = 0.26 +/- 0.02) in all nine subjects; erythrocyte osmotic fragility however was normal. Although some subjects showed acanthocytosis total cholesterol (0.63 +/- 0.05 mol x 10(-6)/mg membrane protein) and sphingomyelin/lecithin ratio (0.905 +/- 0.042) of RBC membranes were normal while plasma from the subject with schistocytosis had a significantly decreased sphingomyelin/lecithin ratio in plasma (17.2 +/- 2.4 vs. 29.1 +/- 3.3) suggesting that sphingomyelin and lecithin are not freely exchangeable between plasma and the outer surface of RBC membranes.

Creatine determinations as an early marker for the diagnosis of acute myocardial infarction

In the acute phase of acute myocardial infarction (3-8 h after onset of symptoms) an early transient increase in the creatine concentration of serum, saliva, and especially of urine can be observed. Due to the renal threshold, urine values give a much better discrimination between infarction patients and controls than do serum determination. In some patients secondary peaks of serum and urine creatine concentrations can be seen about 24-36 h after hospital admission. Intramuscular injections of 5.0 mL of a saline solution and muscular trauma interfere with the test, but with angina pectoris interference is absent or limited. Creatine leakage from myocardium is insufficient to explain the observed creatinuria in infarctions, and intact extra-cardiac tissues are believed to be involved in creatine release.

Measurement of activation energy of gamma-glutamyltransferase as a marker for enzyme heterogeneity

In order to detect differences between various multiple forms of gamma-glutamyltransferase, the activation energy was measured. In the serum of patients with liver diseases, activation energy was measured. In the serum of patients with liver diseases, activation energy of the serum enzyme is higher than in normal individuals (41.9 +/- 1.2 vs. 38.9 +/- 1.5 kJ/mol, p less than 0.05). Neuraminidase treatment resulted in a reduction of activation energy. Various multiple forms of serum gamma-glutamyltransferase, as prepared by lectin affinity chromatography (concanavalin A, Ricinus communis I and II, wheat germ agglutinin) showed activation energy differences between binding and nonbinding fractions. Similar results were observed in seminal plasma gamma-glutamyltransferase, when patients with accessory gland infection were compared with a reference population. Our results suggest that the activation energy depends upon differences in the carbohydrate part of the enzyme. The low gamma-glutamyltransferase activation energy of tissue extracts increased significantly after butanol extraction and was then comparable with serum activation energy values, which suggests that lipid-binding is a factor in activation energy variation. In most cases, gamma-glutamyltransferase activities measured at a certain temperature can be easily converted to a corresponding activity at another temperature, but in severe liver disease significant errors may be introduced when simple temperature conversion factors are used.

Restrictive cardiomyopathy caused by adipositas cordis

Adipositas cordis is a very rare disorder, characterized by fatty infiltration of myofibers. It has been related to dilated or hypertrophic cardiomyopathy and obesity. In this report, however, we present a non-obese patient, presenting with a restrictive syndrome and showing massive infiltration of adipocytes in the interventricular septum, proving adipositas cordis.

Postoperative immunological response against contractile proteins after coronary bypass surgery

The pathogenesis of post-cardiac injury syndrome was studied prospectively in 62 patients who underwent coronary bypass grafting. Preoperative and serial postoperative titres of actin and myosin antibodies were measured by an enzyme linked immunosorbent assay. Perioperative cumulative release of serum aspartate and alanine aminotransferases, lactate dehydrogenase, and creatine kinase was calculated by approximation formulas that are used to estimate infarct size. Complete post-cardiac injury syndrome developed in eight (13%) patients and an incomplete syndrome developed in 16 (26%). There was a significant correlation between frequency and intensity of the syndrome and the ratio of postoperative to preoperative titres of actin and myosin antibodies. Furthermore, there was a significant correlation between the cumulative release of lactate dehydrogenase, serum aspartate aminotransferase, and creatine kinase and the number of coronary vessels that were grafted, but no correlation was found between the incidence of post-cardiac injury syndrome and the number of coronary bypasses grafted or between the cumulative enzyme release and the postoperative immunological response against the major contractile proteins, actin and myosin. The amount of enzymes released during coronary bypass surgery seems to be a good indicator of the extent of myocardial damage during operation but it does not determine either the incidence of post-cardiac injury syndrome or the postoperative immunological response against the main contractile proteins actin and myosin.