[Modification of risk factors through physical training and low-fat diet]

This intervention program investigated the applicability and the effects of intensive physical exercise and low-fat diet on the progression of coronary atherosclerotic lesions and stress induced myocardial ischemia in patients with stable angina pectoris. Patients participating in this study were recruited following routine coronary angiography for angina pectoris. Inclusion criteria were male sex, stable symptoms, a willingness to participate in the study for at least twelve months, and coronary artery stenoses well documented by angiography. Exclusion criteria were unstable angina pectoris, left main coronary artery stenosis greater than 25% luminal diameter reduction, severely depressed left ventricular ejection fraction (less than 35%), significant valvular heart disease, insulin-dependent diabetes mellitus, primary hypercholesterolemia (type II hyperlipoproteinemia, low-density lipoprotein greater than 210 mg/dl), and conditions precluding regular physical exercise. 18 patients participated in this program for one year; they consumed a low-fat, low-cholesterol diet (less than 20 energy % fat, cholesterol less than 200 mg/day) and exercised for more than 3 h/week. Myocardial oxygen consumption was estimated from maximum rate-pressure product at peak exercise; it was correlated to stress induced myocardial ischemia, as measured by 201Tl-scintigraphy. Results were compared with those of 18 matched patients on "usual care". In the intervention group, physical work capacity (161 +/- 34 W vs. 194 +/- 42 W) and maximum rate pressure product (25.0 +/- 6.3 x 10(3) vs. 27.2 +/- 5.3 x 10(3)) increased significantly (p less than 0.01). Patients willing to devote time and effort to intensive physical exercise and to comply with a low-fat diet may benefit from this form of therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Platelet-targeted fibrinolysis enhances clot lysis and inhibits platelet aggregation

BACKGROUND

Although plasminogen activator therapy has been shown to reduce mortality in patients with severe myocardial infarction, several problems fuel the search for more potent and specific thrombolytic agents.

METHODS AND RESULTS

To explore the effect of plasminogen activator targeting to platelets, we covalently linked urokinase that had been modified with N-succinimidyl-3-(2-pyridyldithio)propionate to the Fab' of a monoclonal antibody (7E3) that selectively binds to platelet membrane glycoprotein (GP) IIb/IIIa. In an assay measuring (as reflected by plasmin generation) a plasminogen activator's ability to bind GP IIb/IIIa immobilized on plastic, urokinase-7E3 Fab' produced 31-fold more plasmin than did urokinase (p = 0.0001). The addition of solubilized GP IIb/IIIa blocked this enhancement of plasmin generation, indicating that binding was impaired. Plasmin generation reflecting binding to immobilized intact platelets was 2.4-fold greater for urokinase-7E3 Fab' than for unconjugated urokinase (p = 0.002). In a plasma clot lysis assay, urokinase-7E3 Fab' was at least 25-fold more potent than either urokinase alone or a mixture of urokinase and 7E3 (Fab')2 (p less than 0.009), and potency could be related to platelet concentration in the clot. Ex vivo, ADP-induced platelet aggregation was inhibited by a urokinase-7E3 IgG conjugate at a concentration of 8 nM, whereas a mixture of urokinase and 7E3 (Fab')2 in equimolar amounts required 60 nM and urokinase alone required 1 microM to achieve the same effect.

CONCLUSIONS

Therefore, the targeting of urokinase to the GP IIb/IIIa platelet receptor both accelerates clot lysis (when platelets are associated with a fibrin clot) and inhibits platelet aggregation.

Non-invasive detection of reduced regional myocardial perfusion at rest in patients with unstable angina pectoris: increased regional 81mKr deposition following intravenous injection of 81Rb

The present study was to investigate whether combined imaging of 81Rb and 81mKr distributions after i.v. injection of 81Rb at rest might improve the differentiation between ischemic and irreversibly damaged myocardium as compared to 201Tl scintigraphy at rest. In 21 patients who had undergone diagnostic cardiac catheterization for evaluation of chest pain, 148 MBq ultrapure 81Rb were injected i.v. at rest immediately following 201Tl scintigraphy at rest. Of 14 patients with earlier myocardial infarction, 10 patients revealed decreased regional tracer uptake of 81Rb and/or 81mKr, compared to 12 patients with regional 201Tl uptake abnormalities. In 3 patients with unstable angina pectoris, however, an evident mismatch between either the regional 201Tl or 81Rb distributions and the distribution of 81mKr was observed: in contrast to the reduced uptake of 201Tl and/or 81Rb, 81mKr activity was increased in 3 myocardial segments with normal left ventricular performance but supplied by coronary arteries with high-grade stenoses. In patients with contraindications to exercise tests (e.g. unstable angina) 81Rb/81mKr rest scintigraphy may therefore assist the differentiation between malperfused but potentially viable and irreversibly damaged myocardium.

Effects of lipoprotein (a) on success rate of thrombolytic therapy in acute myocardial infarction

Lipoprotein (a) [Lp(a)] and plasminogen share a high degree of homology as recently evidenced by amino acid and deoxyribonucleic acid analysis. As Lp(a) is enzymatically inactive, it has been suggested that high levels of Lp(a) may suppress the profibrinolytic activity at the cell surface and increase the risk for arteriosclerosis and thrombosis by competitive inhibition of plasminogen. The present study evaluated whether high levels of Lp(a) influence thrombolytic therapy in patients with acute myocardial infarction. Forty-one patients with acute myocardial infarction received a combination low-dose thrombolytic therapy with recombinant tissue-type plasminogen activator (rt-PA) and human single-chain urokinase-type plasminogen activator (scu-PA). This regimen did not induce plasminemia or a lytic state as indicated by well-maintained levels of fibrinogen. Coronary patency was assessed angiographically 90 minutes after initiation of treatment. Thrombolysis was successful in 30 and unsuccessful in 11 patients. Patients with high Lp(a) levels (greater than or equal to 25 mg/dl) (n = 9) responded equally well to thrombolytic therapy (8 of 9, patency 89%) as did patients with normal or low levels of Lp(a) (22 of 32, patency 70%, difference greater than 0.1). Lp(a) levels did not differ significantly between patients with successful and unsuccessful thrombolysis. Our results demonstrate that high levels of Lp(a) do not affect thrombolysis in patients with acute myocardial infarction when low-dose pharmacologic concentrations of rt-PA and scu-PA are applied in combination.

Implantable cardioverter defibrillator: possible hazards of electromagnetic interference

We report on three patients with an automatic, implantable cardioverter defibrillator (AICD, CPI) in whom the device had been deactivated due to electromagnetic interference. In all cases, the source of the electromagnetic disturbances could be identified.

Hemodynamic and neuroendocrine response to acute administration of the phosphodiesterase inhibitor BM14.478 in patients with congestive heart failure

The benzimidazol analogue BM14.478 is a phosphodiesterase inhibitor with both vasodilator and positive inotropic properties. Hemodynamic parameters and plasma hormone levels of 8 patients (1 female, 7 male) with chronic congestive heart failure NYHA Classes II-IV (1 patient with coronary artery disease, 7 patients with primary dilated cardiomyopathy) were assessed before and until 6 h after the intravenous application of 1.0 mg BM14.478. There was a significant decrease of mean pulmonary artery pressure (28 +/- 11 vs. 23 +/- 11 mmHg; p less than 0.05), mean right atrial pressure (8.6 +/- 5.2 vs. 5.0 +/- 4.7 mmHg; p less than 0.02), and systemic vascular resistance (1651 +/- 484 vs. 1206 +/- 252 dynes.s.cm-5; p less than 0.05) as early as 10 min after injection of BM14.478. Pulmonary vascular resistance also was reduced (128 +/- 86 vs. 61 +/- 39 dynes.s.cm-5, 30 min after injection; p less than 0.02). Simultaneously there was a significant increase of cardiac index (2.3 +/- 0.7 vs. 3.1 +/- 0.8 l.min-1.m-2, 10 min after injection; p less than 0.02), and stroke volume index (28.8 +/- 11.7 vs. 33.9 +/- 8.5 ml.min-1.m-2; 30 min after injection; p less than 0.05). Although mean heart rate did not change significantly, some patients reacted with a transient increase. There was also a slight but insignificant increase of the double product. No serious side effects were observed. The hemodynamic improvement was followed by a delayed reduction of plasma levels of epinephrine (51 +/- 20 vs. 41 +/- 21 pg/ml; p less than 0.02; 30 min after injection) and atrial natriuretic peptide (229 +/- 283 vs. 121 +/- 168 pg/ml; p less than 0.05; 1 h after injection). Mean levels of plasma norepinephrine, however, did not change significantly and individual responses showed large variations, which could not be predicted by the behavior of the hemodynamic parameters. Three of eight patients (2 of these with elevated baseline filling pressures) even showed a marked increase of plasma norepinephrine levels after BM14.478. Response of plasma renin activity and plasma vasopressin levels to BM14.478 also was heterogeneous. According to the results of this study, acute administration of the phosphodiesterase inhibitor BM14.478 has an immediate beneficial hemodynamic effect in patients with severe congestive heart failure by reducing both preload and afterload, and by increasing cardiac index and stroke volume. However, this improvement of hemodynamic parameters is not necessarily accompanied by a favorable short-term response of plasma hormones, and therefore does not allow any conclusions on survival of these patients.

[Anti-angina therapy of coronary heart disease. Mono- or combination treatment]

Applying a metaanalysis, it was examined whether a combination of drugs is superior to monotherapy in the treatment of angina pectoris. The three classical groups of anti-anginal drugs, nitrates, calcium channel blockers and beta-receptor blockers were investigated. For data analysis, patients were divided in those suffering from "angina pectoris" and those suffering from "angina pectoris despite monotherapy." In patients with the inclusion criterium "angina pectoris" combination of drugs is not superior to monotherapy. This applies to the evaluation criteria "improvement of symptoms" and "reduction of ischemia". In patients with the inclusion criterium "angina pectoris despite monotherapy" however, there is a clear superiority of drug combination as compared to monotherapy. Again this applies to the evaluation criteria "improvement of symptoms" and "reduction in myocardial ischemia". With respect to antianginal efficacy all three possible combinations appear to be similar. If the evaluation criterium is "improvement of prognosis" no data are available with regard to drug combination. Furthermore no data are available on the prognostic effect of an anti-anginal therapy in patients with stable angina pectoris. A significant improvement of prognosis could be demonstrated for beta-receptor blocking agents without ISA in unstable angina, acute myocardial infarction, and in the postinfarction period. The effect of calcium channel blockers on prognosis depends on the substance class applied and on the presence or absence of signs of congestive heart failure. Monotherapy with nifedipine in instable angina and acute myocardial infarction fails to improve prognosis, and there even may be a tendency to adverse effects. In the absence of signs of congestive heart failure verapamil has been demonstrated to improve prognosis in the post infarction period. Likewise, improvement of prognosis by the administration of diltiazem in acute myocardial infarction only could be demonstrated in patients without signs of heart failure. In contrast, in patients with signs of congestive heart failure diltiazem increased the rate of reinfarction and mortality. For nitrates only in acute myocardial infarction a trend towards improved prognosis has been shown. Especially for nitrates the data on prognosis in coronary heart disease available so far are not convincing.

Transcription, storage and release of atrial natriuretic factor in the failing human heart

1. In this study the relationship between the synthesis of atrial natriuretic factor at the level of atrial natriuretic factor mRNA and the atrial storage and circulating plasma levels of atrial natriuretic factor were investigated in 15 patients with heart failure. The patients underwent right and left heart catheterization before cardiac surgery for valve replacement or coronary artery bypass grafting. 2. Plasma concentrations of atrial natriuretic factor were correlated to atrial levels of atrial natriuretic factor mRNA. Atrial levels of atrial natriuretic factor mRNA and plasma concentrations of atrial natriuretic factor exhibited a close correlation to both pulmonary artery pressure and left atrial pressure. No relationship, however, could be found between the right atrial content of atrial natriuretic factor and both the expression of atrial natriuretic factor mRNA in the atria and the plasma levels of atrial natriuretic factor. 3. From these data it may be concluded that increased plasma levels of atrial natriuretic factor in the pressure- and/or volume-overloaded heart are associated with an elevated level of atrial natriuretic factor mRNA. We suggest that not only plasma levels of atrial natriuretic factor but also the expression of atrial natriuretic factor in the atrial are related to left ventricular filling pressures in the failing human heart.

[The noninvasive diagnosis of coronary heart disease in women. The exercise ECG or ST-segment analysis in the long-term ECG?]

The diagnostic value of an exercise ECG in women with the clinical symptoms of stable angina is limited because of its low accuracy in demonstrating coronary heart disease. A study of ambulatory patients was undertaken, involving 143 men and 29 women (mean age 55 [37-70] years), to determine whether ST-segment analysis of the 24-hour ECG gives better results, the coronary arteriogram providing the standard of comparison. 24-hour monitoring and the exercise ECG gave similar diagnostic results (66% vs 67%) in the 143 men. But in the 29 women 24-hour monitoring was diagnostically superior to the exercise ECG (76% vs 45%; P less than 0.01), as a result of a significantly higher specificity (64% vs 29%; P less than 0.05) and a tendency towards higher sensitivity (87% vs 60%; P = 0.13). As expected, the accuracy of the exercise ECG was thus lower in women than in men (P less than 0.05). There were no significant gender-specific differences for accuracy of 24-hour monitoring (76% in women, 66% in men; P less than 0.15). These data indicate that in women ST-segment analysis of the 24-hour ECG is better than the exercise ECG for demonstrating coronary heart disease.

Fibrinolytic therapy of deep vein thrombosis with continuous intravenous infusion of a recombinant tissue plasminogen activator

Recombinant human rt-PA was administered to 22 patients with deep vein thrombosis at a dosage of 30 to 120 mg/day (0.5 to 1.76 mg/kg body weight/24 hr) over 2 to 10 days. rt-PA induced phlebographically documented substantial recanalization in 18 of 21 patients. The lowest dose of 0.5 mg/kg/24 hr tested here was thrombolytically effective, whereas a dose of 0.95 mg/kg/24 hours and more led to hemorrhagic complications and premature discontinuation of therapy in four of six patients. Blood clotting analysis did not reveal any substantial decrease in fibrinogen concentrations, whereas the euglobulin clot lysis time and thromboelastography demonstrated a systemic fibrinolytic effect. Therapy with rt-PA can thus be considered as an alternative and effective method of therapy in treatment of deep vein thrombosis. The results of this study show that even a dosage of lower than 0.5 mg/kg/24 hr might prove to be effective. Further studies would be required to show whether the fibrin specificity of rt-PA leads to a superiority of this fibrinolytic substance over the conventional thrombolytic agents, streptokinase and urokinase.

[Different rates of progression of heart valve defects]

In order to determine the rate of progression in valvular heart disease, the records of patients with simple valve lesions and two cardiac catheterizations performed prior to surgery were examined retrospectively. In 53 patients (mitral regurgitation n = 16, aortic regurgitation n = 13, mitral stenosis n = 13, aortic stenosis n = 11) complete data were available. The time interval between the two studies averaged 47 +/- 24 months. In patients with mitral regurgitation left ventricular ejection fraction deteriorated significantly faster than in the other groups; the rate of left ventricular volume gain and rise in pulmonary pressure also tended to be higher in this group. The transvalvular gradient in aortic stenosis showed a highly significant increase during the observation period (56 +/- 26 mm Hg vs 78 +/- 29 mm Hg; p less than 0.01), however, left ventricular ejection fraction remained within normal limits. These data indicate that patients with mitral regurgitation should be followed closely prior to valve replacement.

Improvement of diastolic filling in hypertensive patients treated with cilazapril

The aim of this study was to assess the behavior of the diastolic left ventricular (LV) filling pattern and cardiac hypertrophy after treatment with cilazapril. Twelve patients (9 male and 3 female) with mild to moderate essential hypertension, aged 46 +/- 14.1 years, were treated with cilazapril for 1 year. They underwent Doppler echocardiography at the beginning (I), after 6 months (II), and after 1 year (III) of treatment. The following parameters were evaluated: mean arterial pressure (MAP) automatically recorded for 24 h, interventricular septal and posterior wall thickness, LV and end-diastolic diameter, LV mass index, early (E) and late (A) diastolic filling flow velocities, and the ratio E/A. A significant reduction in LV hypertrophy and an improved diastolic filling pattern of the left ventricle was shown after 6 months of therapy with cilazapril; this improvement still remained after 1 year of therapy.

Non-Invasive Detection of Reduced Regional Myocardial Perfusion at Rest in Patients with Unstable Angina Pectoris: Increased Regional 81mKr Deposition following Intravenous Injection of 81 Rb

The present study was to investigate whether combined imaging of 81 Rb and 81mKr distributions after i.v. injection of 81 Rb at rest might improve the differentiation between ischemic and irreversibly damaged myocardium as compared to 201TI scintigraphy at rest. In 21 patients who had undergone diagnostic cardiac catheterization for evaluation of chest pain, 148 MBq ultrapure 81 Rb were injected i.v. at rest immediately following 201TI scintigraphy at rest. Of 14 patients with earlier myocardial infarction, 10 patients revealed decreased regional tracer uptake of 81 Rb and/or 81mKr, compared to 12 patients with regional 201TI uptake abnormalities. In 3 patients with unstable angina pectoris, however, an evident mismatch between either the regional 201TI or 81 Rb distributions and the distribution of 81mKr was observed: in contrast to the reduced uptake of 201TI and/or 81 Rb, 81mKr activity was increased in 3 myocardial segments with normal left ventricular performance but supplied by coronary arteries with high-grade stenoses. In patients with contraindications to exercise tests (e.g. unstable angina) 81Rb/81mKr rest scintigraphy may therefore assist the differentiation between malperfused but potentially viable and irreversibly damaged myocardium.

Dual sensitization of the adrenergic system in early myocardial ischemia: independent regulation of the beta-adrenergic receptors and the adenylyl cyclase

Acute myocardial ischemia provokes sensitization of the adenylyl cyclase system. This sensitization can be differentiated in a receptor-specific and an enzyme-specific sensitization. The receptor-linked sensitization is characterized by an increase of beta-adrenergic receptors in the plasma membranes after 15 mins of global ischemia (49.8 +/- 3.6 to 67 +/- 6 fmol/mg protein) followed by a further increase (89 +/- 4 fmol/mg protein) after 50 min of ischemia in isolated perfused hearts. Concomitantly functionally coupled receptors which are able to bind the beta-agonist with high affinity, increased by 32% after 15 min and by 57% after 50 min of ischemia. The affinities of the receptors for their agonists or their antagonists remain unchanged. Maximally isoproterenol-stimulated adenylyl cyclase activity rose from 66 +/- 7 to 101 +/- 10 pmol cAMP/min/mg protein after 15 min of global ischemia indicating the beta-receptor-specific sensitization of the beta-adrenergic system. This sensitization was followed by a gradual decline of the adenylyl cyclase activity after 30 and 50 min of global ischemia. Additionally, 15 min of myocardial ischemia induced an enzyme-linked sensitization of the adenylyl cyclase activity as indicated by an increase of the forskolin-stimulated activity by about 25% (300 +/- 20 vs 378 +/- 25 pmol cAMP/min/mg protein). In contrast after 50 min of ischemia the total adenylyl cyclase activity declined (232 +/- 24 pmol cAMP/min/mg protein) despite the persistent increase of beta-adrenergic receptors in the plasma membranes. These data demonstrate that the enzyme-specific sensitization is only transient. The early sensitization and late inactivation of the adenylyl cyclase activity occurred independently of receptor activation and could not be prevented by beta-blockade (10(-6) M alprenolol). Cyanide perfusion (1 mM), used to block energy metabolism, lead to energy depletion similar to acute myocardial ischemia. This resulted in an increase of functionally coupled receptors with a time course comparable to that of global ischemia. Additional perfusion with desensitizing concentrations of the beta-agonist isoproterenol did not induce uncoupling or internalization of beta-adrenergic receptors in cyanide treated hearts, suggesting that the rise in functionally coupled receptors is due to a redistribution in part caused by the abolition of continuous receptor internalization. In contrast, the enzyme-linked sensitization is independent of cellular localization of the beta-adrenergic receptors. The increased activity was carried by the enzyme even after partial purification with solubilization and wheat germ affinity chromatography. These data suggest an ischemia-induced, covalent modification of the adenylyl cyclase.(ABSTRACT TRUNCATED AT 400 WORDS)

Electrophysiologic effects of bepridil in patients with refractory ventricular tachycardia assessed by programmed electrical stimulation

The effect of intravenous bepridil, a new calcium antagonist with class I and III properties, was tested in 21 patients with sustained ventricular tachyarrhythmias refractory to a mean of five antiarrhythmic agents as assessed by programmed right ventricular stimulation. At control electrophysiologic study without antiarrhythmic agents, sustained monomorphic ventricular tachycardia (VT) was initiated in 20 patients and ventricular fibrillation (VF) was initiated in one patient. After 3 mg/kg of bepridil was administered, VT was still inducible in 19 patients (3 patients had self-terminating VT); the other 2 patients had no inducible VT after bepridil. Bepridil prolonged significantly the QTc interval, the effective refractory period, and the cycle length of induced ventricular tachycardia. Two patients with no inducible VT after intravenous bepridil were placed on oral bepridil (300 mg/day). One patient died suddenly and one patient died of progressive heart failure. The results seem to indicate that the efficacy of bepridil in patients with refractory ventricular tachycardia is limited.

ACE inhibition improves vagal reactivity in patients with heart failure

The deranged autonomic control of heart rate was studied in 34 patients with heart failure (New York Heart Association [NYHA] functional class II to III) by examining the carotid sinus baroreflex. The carotid sinus baroreceptors were stimulated by graded suction. The slope of the regression line between increases in cycle length and the degree of neck suction was taken as an index of baroreflex sensitivity. The reflex response is mediated by a selective increase of vagal efferent activity. Baroreflex sensitivity therefore represents a measure of vagal reactivity. Using multiple regression analysis, baroreflex sensitivity (BS) correlated positively to stroke volume index (SVI) and inversely to plasma renin activity (PRA) and to age: BS = 0.47 SVI - 0.38 PRA - 0.23 age + constant (r = 0.74; p less than 0.0005). In addition to digitalis and diuretics, angiotensin-converting enzyme (ACE) inhibitors (captopril or enalapril) were given to 16 patients for a mean of 17 +/- 3 days. The patients with hemodynamic improvement (group A) exhibited improved baroreflex sensitivity (1.4 +/- 0.4 to 3.6 +/- 1.2 msec/mm Hg; p less than 0.01). Baroreflex sensitivity remained unchanged (3.1 +/- 0.8 to 2.4 +/- 1.0 msec/mm Hg; n.s.) in the patients without hemodynamic improvement (group B). The increase in reflex sensitivity did not correlate with hemodynamic alterations. Baroreflex sensitivity during ACE inhibition (BSD) was only related to the baseline baroreflex sensitivity (BSB): BSD = 2.8 BSB - 0.46 (r = 0.84; p less than 0.005). In patients with heart failure, reflex bradycardia decreases with age and with PRA and increases with stroke volume. Chronic therapy with ACE inhibitors enhances vagal reactivity in patients with hemodynamic improvement.

[24-hour blood pressure and renal function in cardiac failure during the titration phase of captopril and enalapril]

In 33 patients with heart failure (NYHA II-III) 24-h blood pressure was examined during the titration of two ACE-inhibitors. Blood pressure was measured by the oscillometric method using the blood pressure monitor 90202 from SpaceLabs, Inc. The measurements were taken from 06.00 to 22.00 hours every 20 min, and from 22.00 to 06.00 hours every 1 h. All patients received an additional therapy, either with captopril (group 1, n = 17) or enalapril (group 2, n = 16) in random order. Serum-electrolytes, serum-creatinine, and plasma-renin activity were measured before and during therapy with both ACE-inhibitors. 24-h blood pressure measurements were taken before and on the first and fifth day of the treatment with ACE-inhibitors. The groups did not different in respect to the degree of heart failure, the concomitant medication, or the 24-h profiles of blood pressure and heart rate. The mean initial doses of captopril was 9.2 +/- 1.2 mg. Each patient of group 2 received an initial dose of 2.5 mg enalapril. The maximal decrease of diastolic blood pressure occurred after 1 h in group 1 and after 4 h in group 2 and was similar in both groups (8 vs, 7 mmHg). The 24-h blood pressure values on day 5 were consistently below the pretreatment values (p less than 0.005). Heart rate was not affected by either ACE-inhibitor. The groups did not differ significantly during ACE-inhibition in their 24-h blood pressure and heart rate profiles. Before treatment, serum-sodium, -potassium and -creatinine were within the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)

[Noninvasive determination of left ventricular diastolic filling parameters using Doppler echocardiography before and after coronary angioplasty (PTCA)]

Impaired ventricular diastolic filling may be an early sign of myocardial ischemia. To study the influence of coronary angioplasty (PTCA) on diastolic filling, 40 patients with coronary heart disease (CHD) were studied by pulsed two-dimensional Doppler echocardiography (2DDE) before and after PTCA. In six patients PTCA was not successful and 2DDE indices of ventricular filling did not change significantly. In 34 patients with successful PTCA, peak early diastolic velocity (E) increased by 8.5% (p less than 0.03), the ratio (E/A) of peak early vs peak late diastolic velocity by 11.2% (p less than 0.005) and the diastolic filling time per minute (diast.-t/min) by 4.6% (p less than 0.01). In patients with impaired diastolic filling before PTCA (group I, n = 28) the changes in diastolic filling were even more pronounced. Patients with unimpaired diastolic filling properties before PTCA did not show significant alterations (group II, n = 6). Seventeen patients were examined 3 h and 24 h after PTCA. The changes in diastolic filling parameters apparent already 3 h after PTCA were even more pronounced after 24 h. According to these data, PTCA improves left ventricular diastolic filling. These changes are more pronounced 24 h compared to 3 h after PTCA.

Activation and decreased deformability of neutrophils after intermittent claudication

This study investigated local alterations in neutrophil activation and deformability after intermittent claudication. In 17 patients with one-sided peripheral arterial occlusive disease, neutrophil count, proportion of activated neutrophils (by nitro blue tetrazolium test), and neutrophil filterability as a measure of passive deformability were assessed in the femoral arterial and venous blood of the diseased leg and in the femoral venous blood of the healthy leg (n = 10). The values were obtained at rest, immediately after claudication, and 10 minutes after claudication induced by repetitive toe stands. Immediately after exercise, the arterial and venous blood differences in the diseased leg were 1) neutrophil count, 9% (95% confidence interval [CI], 5-14%; relative increase in the venous blood compared with arterial blood); 2) the proportion of activated neutrophils, 26% (CI, 10-42%); and 3) the neutrophil filterability, -10% (CI, -4% to -15%). At rest and 10 minutes after exercise, neutrophil parameters did not differ significantly between the femoral arterial and venous blood. Furthermore, no arterial and venous blood differences in the neutrophil parameters were found in the healthy leg. In addition to local changes, systemic changes occurred immediately after exercise. In the femoral arterial blood, the total neutrophil count had risen by 13% (CI, 8-18%), the proportion of activated neutrophils had risen by 41% (CI, 25-58%), and average neutrophil rigidity had risen 17% (CI, 11-22%) compared with the values obtained before exercise. At 10 minutes after exercise, all neutrophil parameters were still elevated. We conclude that even short periods of ischemia, as in intermittent claudication, cause local alterations in neutrophil function and distribution.

Adrenergic receptors and sensitization of adenylyl cyclase in acute myocardial ischemia

Acute myocardial ischemia leads to a gradual increase in beta-adrenergic receptors at the cell surface. This increase occurs rapidly after onset of global ischemia (15 minutes) and persists even after prolonged periods of global ischemia. This alteration can be observed both in vivo and in vitro in isolated perfused hearts. Several groups have previously shown that ischemia induces a local release of endogenous catecholamines. Here, we show that these endogenous catecholamines are sufficiently high to induce receptor desensitization with internalization of beta-adrenergic receptors in normal hearts. In acute myocardial ischemia, however, agonist-promoted internalization and functional uncoupling of beta-adrenergic receptors is abolished. Consequently, the balance of internalization and externalization of receptors is shifted toward an increase in functionally coupled receptors at the cell surface. Similarly, but inconsistently, the density of alpha 1-adrenergic receptors in the plasma membrane is increased in acute myocardial ischemia. In regard to function, the increase of coupled beta-adrenergic receptors leads to an augmented responsiveness of the adenylyl cyclase system to beta-adrenergic stimulation. This receptor-specific sensitization is superimposed by a transient increase of total adenylyl cyclase activity in the very early phase of global ischemia (0-20 minutes). The enhanced activity of adenylyl cyclase to direct stimulation is tightly associated with the partially purified enzyme, suggesting a covalent modification of the enzyme molecule. However, after prolonged periods (greater than 30 minutes) of global ischemia, the ischemia-induced enzyme-specific sensitization is displaced by a general reduction in enzyme activity, both in vivo and in vitro. The persistent sensitization at the receptor level then meets an unresponsive adenylyl cyclase.(ABSTRACT TRUNCATED AT 250 WORDS)

[Recurrent ventricular fibrillation in a patient with angiographically normal coronary arteries and intermittent ST segment elevation]

We report on a patient who was admitted to the hospital because of severe angina pectoris. During hospitalization extensive ECG alterations and intermittent ventricular fibrillation were observed. However, coronary angiography showed normal coronary arteries and left ventricular function. Treatment with high-dose nitrates and Ca-antagonists gradually improved the patient's clinical situation. Although a Prinzmetal angina seemed likely, a vasculitis of the coronary arteries could not be excluded with certainty. Therefore, additional corticoid therapy was administered to the patient. After 5 weeks the patient was discharged from the hospital without any pathological clinical symptoms.

Randomized controlled study of heparin and low molecular weight heparin for prevention of deep-vein thrombosis in medical patients

166 patients aged 40-80 years were included in a controlled, randomized, double-blind study to determine the efficacy and safety of a single daily injection of a low molecular weight (LMW) heparin for prevention of deep-vein thrombosis compared to low dose conventional heparin. Patients received 1 x 1.500 aPTT units of a LMW heparin fraction (plus 2 x placebo injection) or 3 x 5.000 IU of an unfractionated heparin. During 10 days of treatment, patients underwent repeated clinical investigation, serial impedance plethysmography, and Doppler sonography for detection of thrombosis of the lower limbs. Combined application of these methods revealed evidence of thrombosis in 4.5% of patients on unfractionated heparin and 3.6% of patients on LMW heparin. Subcutaneous hematomas were significantly smaller in diameter upon treatment with LMW heparin (p less than 0.001). Antithrombin III levels were significantly higher at the end of the observation period in the LMW heparin group (p less than 0.005). Thrombocyte count, transaminases, creatinine, and haemoglobin did not change in either group. The results indicate that LMW heparin administered by a single s.c. dose daily may be as effective as low dose heparin in prevention of deep venous thrombosis in medical inpatients.