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L R Krusell

Publications and source records attributed to L R Krusell.

At least 19 recordsLinked to original sources
PubMed1994

Observer variation in the interpretation of ventilation-perfusion lung scintigraphy.

The diagnosis of pulmonary embolism (PE) remains one of the most difficult in clinical medicine, and the diagnostic value of lung scintigraphy has been questioned. To evaluate the observer variation in the interpretation of ventilation-perfusion lung scanning in the diagnosis of PE, 87 lung scintigrams from consecutive patients with phlebography-proven deep venous thrombosis and without clinical signs of PE were randomly mixed with 50 reference lung scintigrams from patients with PE symptoms. The scintigrams were reevaluated blind by two experienced clinical physiologists. Each observer evaluated each lung scintigram twice and recorded whether the lung scan was normal or abnormal. If it was abnormal, the location and number of segment defects were registered. The intraobserver agreement, including number and location of segments, ranged from 0.77 to 0.85 and for the diagnosis of PE from 0.88 to 0.92 with a kappa of 0.80-0.84. The values for the interobserver agreement for the diagnosis of PE were 0.73-0.80 with a kappa of 0.56-0.67. It is concluded that in the interpretation of ventilation-perfusion lung scintigraphy the use of a simple scheme-deciding whether there is segmental ventilation-perfusion mismatch or not-has a good reproducibility with a high kappa for inter- and intraobserver variation and can serve as a simple routine method for diagnosing PE.

Double-Blind Method↗
PubMed1992

Alpha-adrenoceptor blockade in patients with mild to moderate hypertension: long-term renal effects of doxazosin.

Using constant infusion technique and a water-loading procedure, we investigated renal hemodynamic and excretional variables in 15 essential hypertensive patients [diastolic blood pressure (DBP) 102 +/- 10 mm Hg] after 3 weeks of placebo and after 16 weeks of treatment with a postjunctional alpha 1-adrenoceptor-antagonist, doxazosin (1-16 mg) once daily. A minor decrease in supine DBP (p less than 0.05) but no significant changes in systolic BP (SBP) and heart rate (HR) were observed. No significant changes were noted in glomerular filtration rate (GFR), renal plasma flow (RPF), and renal vascular resistance (RVR). The mean renal excretion rate of sodium, potassium, uric acid, and albumin for the entire group was unaffected by the treatment, but the individual changes in sodium clearance correlated significantly with changes in mean BP (r = 0.64, n = 15, p less than 0.05). Six patients showed an increase in sodium excretion after treatment, whereas nine showed a decrease. No decrease in mean body weight was noted, but the BP reduction after 5 months of treatment correlated significantly with the changes in body weight (r = 0.62, n = 15, p less than 0.01). The results indicate that long-term treatment with doxazosin had no deleterious effect on renal function, but the effects on BP were rather modest. The individual BP response is probably determined by the degree of fluid retention even if an intact pressure-natriuresis relationship could still be demonstrated during chronic therapy.

Adrenergic alpha-Antagonists↗
PubMed1992

Combined actions of isradipine and captopril on renal function in hypertension.

The object of this study was to test the hypothesis that the natriuretic and uricosuric effect of calcium-entry blockers could be mediated through antagonism of angiotensin II dependent intrarenal mechanisms. The antihypertensive efficacy, haemodynamic and excretional effects of superimposed calcium blockade with isradipine were investigated in seven hypertensives with unsatisfactorally controlled blood pressure with captopril 50 mg twice daily. Glomerular filtration rate (GFR) and renal plasma flow (RPF), clearances (C) of sodium (Na), potassium (K), uric acid (UA) and lithium (Li), were measured before and after a low-dose bolus of isradipine, i.v. Subsequently, measurements were repeated during constant i.v. infusion of a higher dose with definite systemic haemodynamic effects. After 4 months of combined treatment with isradipine and captopril renal investigations were carried out again. The low isradipine dose induced a slight but statistically significant increment in CNa (22% +/- 28) and heart rate (4% +/- 4), whereas no other variables changed significantly. Infusion of the high isradipine dose caused a pronounced fall in renal vascular resistance (27% +/- 14), systolic (8% +/- 2) and diastolic blood pressure (17% +/- 5). RPF increased significantly (15% +/- 18) whereas no changes were noted in GFR, filtration fraction and urinary albumin excretion rate. In spite of the pronounced fall in BP during the high dose infusion, significant increments in natriuresis (91% +/- 63) and diuresis (41% +/- 27) were induced. The natriuresis was caused by a proximal tubular action as indicated by increased CLi and CLi/GFR.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Normal serum levels of calcitonin gene-related peptide (CGRP) in mild to moderate essential hypertension.

Calcitonin gene-related peptide (CGRP), a highly potent vasodilator, is expressed from the calcitonin-gene and has been localized to nerve fibers of the cardiovascular system, suggesting involvement in the physiologic regulation of vascular tone. In this investigation serum concentrations of CGRP were measured in patients with untreated mild to moderate essential hypertension (WHO I-II) and compared with concentrations in sex- and age-matched normal controls to assess a possible relationship between changes in concentrations of CGRP and this condition. The study showed no significant difference in concentrations of CGRP between patients and the normotensive controls. However, a weak but significant positive correlation was found between systolic (SBP), diastolic (DBP), mean blood pressures (MBP), and circulating concentrations of CGRP when calculated for all individuals included in the study. No correlation was found between heart rates (HR) and concentrations of CGRP. In the normotensive control group, but not in patients with hypertension, a significant positive correlation was present between body weights and concentrations of CGRP. These findings do not support the hypothesis that low expression of CGRP plays a causal role in essential hypertension, but the results do not exclude a potential receptor defect for CGRP to be involved in the disease.

Calcitonin Gene-Related Peptide↗
PubMed1989

[Acetylsalicylic acid in the treatment of arterial thromboembolic diseases. 1. Pharmacologic aspects].

The possible antithrombotic potential of acetyl salicylic acid (ASA) has been established in recent years and the preparation has been employed extensively in ischaemic cardiac disease and cerebrovascular conditions. The inhibiting effect of ASA on platelet function by means of blocking of cyclo-oxygenase is mentioned and, similarly, the presumed role in thrombosis development and atherogenesis is mentioned. ASA's pharmacokinetics are illustrated with emphasis on optimal anti-thrombotic ASA dosage, in particular, in relation to the effects of the preparation on the thromboxan A2 (TxA2)/prostacyclin (PGI2)-ratio. This is probably best achieved by means of low oral dosage in the form of sustained-release ASA formulation where the inhibition of platelet function probably occurs mainly in the presystemic circulation. It is concluded that a daily dosage of 80-100 mg ASA ensures effective and rapid inhibition of TxA2 production. Administration of 30-50 mg ASA daily results in a corresponding blockage of TxA2 production but not until after treatment for three to four days.

Aspirin↗
PubMed1989

[Acetylsalicylic acid in the treatment of arterial thromboembolytic diseases. 2. Clinical documentation].

A review of the literature is undertaken to account for the current status of acetylsalicylic acid (ASA) in the treatment of patients with arterial thrombo-embolic conditions. Employment of ASA monotherapy has been documented to be effective in clinically controlled investigations in patients with unstable angina pectoris, transient cerebral ischaemia, coronary by-pass and femoro-popliteal endarterectomy and introduction of vascular prostheses and, in addition, in primary and secondary prophylaxis of acute myocardial infarction (AMI). In combination with dipyridamol, ASA has been found to be effective in secondary AMI prophylaxis, coronary by-pass operation and in peripheral arteriosclerosis. In patients with cardiac valvular prostheses, conventional anticoagulation therapy must still constitute the basic treatment but dipyridamol may be employed to increase the antithrombotic efficacy of the treatment. The dosage of ASA in the majority of works has been about 1,000 mg daily while isolated investigations have shown good effect from doses as low as 60 mg daily. It appears to be important for the efficacy of the treatment with platelet inhibitors in the above-mentioned conditions that treatment is instituted rapidly and, in connection with operative intervention, preferably preoperatively. In other clinical conditions such as preeclampsia, hypertension in pregnancy, diabetic angiopathy and nephropathy, membranoproliferative glomerulonephritis and arterio-venous shunts with haemodialysis, treatment with ASA appears to be effective but documentation in extensive clinically-controlled investigations is not yet available. The duration of treatment with ASA in arterial thrombo-embolic disease does not appear to be illustrated unanimously in the articles published but, as the atherosclerotic lesion is not influenced by ASA, there are indications for life-long therapy.

Aspirin↗
PubMed1989

Long-term effects of isradipine on blood pressure and renal function.

The hemodynamic and renal effects of isradipine were investigated in 10 hypertensive patients treated for 3.5 months and in a further nine patients treated for two years. Both groups achieved significant and sustained reductions in systolic blood pressure/diastolic blood pressure (-15 percent/-12 percent and -15 percent/-20 percent, respectively; p less than 0.001). Renal parameters were investigated two to three hours after the morning dose of isradipine, using a water-loading procedure. After 3.5 months of treatment, the glomerular filtration rate and renal plasma flow showed small increases (+6 percent and +9 percent, respectively, p less than 0.05), whereas, after two years, these changes were no longer present (+4 percent and 0 percent). Clearance of sodium and uric acid was increased by 40 percent (p less than 0.01) and 21 percent (p less than 0.01), respectively, after 3.5 months, and by 45 percent (p less than 0.05) and 23 percent (p less than 0.01), respectively, after two years. Lithium clearance studies revealed the natriuretic effect to be located in the proximal tubule. After 3.5 months, a significant relationship was found between the blood pressure response and the change in sodium excretion, but this relationship also was no longer present after two years. In conclusion, because of a maintained blood pressure-lowering effect while preserving renal function, and sustained natriuretic and uricosuric actions, isradipine can be considered a promising agent in the long-term treatment of arterial hypertension.

Antihypertensive Agents↗
PubMed1989

Differential effects of isradipine and atenolol on peripheral hemodynamics and arterial compliance.

In a double-blind parallel-group randomized study, 28 patients with essential hypertension (World Health Organization class I/II) were allocated in equal numbers to one of two groups for treatment with either isradipine 5 to 20 mg twice daily or atenolol 50 to 100 mg once daily. At the end of the study, 12 patients were evaluable in the isradipine group and nine in the atenolol group. Assessments at baseline and after 20 weeks of treatment included arterial and venous compliance, mean peripheral perfusion pressure, heart rate, and digital vascular resistance using photoplethysmography. Isradipine had a direct relaxing effect on the arterioles, revealed by a significant increase in arterial compliance and a concomitant normalization of the digital vascular resistance. Atenolol had no significant effect on these parameters but, as expected, it lowered the heart rate, which was not affected by isradipine in the long term. The venous compliance remained low in both groups and, since isradipine--unlike atenolol--is known to have venodilating properties in vitro, its lack of effect in vivo is most likely due to reflex activation of sympathetically mediated venous tone. Because of the preference of isradipine for the arterial side of the peripheral vascular tree, the mean peripheral perfusion pressure remained higher in this group than in the atenolol group, although central systemic blood pressure was lowered equally and satisfactorily in both groups.

Antihypertensive Agents↗
PubMed1989

Bepridil versus verapamil in stable angina pectoris--a controlled clinical trial.

The calcium antagonist bepridil (bepridil monohydrochloride monohydrate, Org 5730, Cordium) was investigated in comparison with verapamil in a double-blind cross-over design in patients with angina pectoris. Exercise parameters, frequency of anginal attacks, consumption of nitroglycerin and subjective preference were analysed for 36 patients. The exercise capacity, estimated by exercise time and total work load during standard bicycle testing, was significantly more improved with bepridil treatment than with verapamil treatment. No significant differences were observed in frequencies of anginal attack, consumption of nitroglycerin and subjective preference. Side effects were mild and equally divided over both treatment groups.

Adult↗
PubMed1989

Acetylsalicylic acid 100 mg and 1000 mg daily in acute myocardial infarction suspects: a placebo-controlled trial.

Of 1078 patients admitted to the coronary care unit with acute chest pain, 293 who had possible acute myocardial infarction and symptoms of median 4 h duration were randomized to treatment with acetylsalicylic acid (ASA) 100 mg daily, 1000 mg daily or placebo for 3 months. During hospitalization, the combined incidence of cardiac death and non-fatal myocardial infarction on-treatment (withdrawals not included) was significantly lower (P less than 0.02) in the 100 mg group (7.1%) than in both the 1000 mg group (20.8%) and the placebo group (19.7%). During later time periods of treatment and at all time periods analysed according to the intention-to-treat principle (withdrawals included), data suggested the same trend, but differences were not statistically significant. Collagen-induced platelet aggregation and serum thromboxane B2 were reduced to the same degree in the two ASA groups and were normal in the placebo group. The data suggest that low-dose ASA could be cheap and safe as first-aid therapy in myocardial infarction suspects.

Aspirin↗
PubMed1988

[Doxazocin].

Explore the source record for details and available documents.

Animals↗
PubMed1988

Effect of bepridil on metabolic control and insulin secretion in diabetics.

In a double-blind cross-over study bepridil 900 mg followed by 300 mg daily for 11 days was given to 37 insulin (Type I) or non-insulin (Type II)-dependent diabetic patients. It did not modify the metabolic control of the patients as levels of glucose in blood and urine, doses of insulin and oral hypoglycaemic drugs, energy intake, and the number of hypoglycaemic attacks during therapy were unchanged. The serum concentration of C-peptide was not modified in either type of diabetic patient, and serum insulin in the Type I but not in the Type II patients was slightly higher during active drug treatment. No adverse organotoxic or arrhythmogenic effects or changes in possible atherogenic lipid fractions in serum could be demonstrated during bepridil therapy.

Adult↗
PubMed1987

Multicenter, double-blind comparison of doxazosin and atenolol in patients with mild to moderate hypertension.

In a double-blind multicenter study, the new alpha 1-adrenoceptor inhibitor doxazosin was compared with atenolol for efficacy, safety and effect on serum lipids. One hundred and twenty-six patients with mild to moderate hypertension were randomly assigned to receive either doxazosin (n = 63) or atenolol (n = 63). The mean final dosages, administered once daily, to obtain 24-hour blood pressure (BP) control were doxazosin 12 mg (range 1 to 16) and atenolol 91.8 mg (range 50 to 100). Of 12 doxazosin and 7 atenolol patient withdrawals from the study, 7 doxazosin and 4 atenolol patients withdrew for treatment-related reasons. No statistically significant differences between treatment groups were found after 20 weeks in changes from baseline in standing and sitting BPs measured 24 hours after administration. Sitting BP (systolic/diastolic) was reduced by 10.5/9.8 mm Hg after doxazosin treatment and by 10.9/10.7 mm Hg after atenolol therapy. Standing BP was reduced by 8.8/7.7 mm Hg after doxazosin administration and 9.7/9.3 mm Hg after treatment with atenolol. Supine BP was measured in a small cohort of the study population, and doxazosin had a smaller effect than atenolol. After 20 weeks of treatment, both drugs reduced heart rate with atenolol producing a statistically significantly greater decrease than doxazosin (standing, doxazosin 5 beats/min, atenolol 16.2 beats/min, p less than 0.001; sitting, doxazosin 5 beats/min, atenolol 13.1 beats/min, p less than 0.001). Side effects were reported by 37 patients receiving doxazosin therapy and 34 patients receiving atenolol therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic alpha-Antagonists↗
PubMed1987

Acute natriuretic effect of nifedipine in hypertensive patients and normotensive controls--a proximal tubular effect?

The acute effects of buccal nifedipine 20 mg on blood pressure, renal haemodynamics and electrolyte excretion were compared in 16 untreated patients (HT) with uncomplicated arterial hypertension (WHO I-II), 11 normotensives (NT) and 6 normotensives given a placebo. Nifedipine caused a significant fall in the systolic and diastolic blood pressures (BP) of 25.7 +/- 12/26.5 +/- 10 mmHg in the hypertensives, and a minor but significant fall in diastolic BP in the normotensives. Renal vascular resistance fell significantly and renal plasma flow was increased non-significantly in the hypertensives. No changes in these parameters were seen in NT. Glomerular filtration rate remained constant in all groups, also in HT despite the marked haemodynamic changes. Natriuresis was significantly increased to the same degree in the HT and NT groups, in spite of their different haemodynamic responses. Uric acid excretion showed a parallel acute increase in both groups. The significant and close relationship between the acute changes in the excretion of sodium and uric acid provides evidence for a proximal tubular natriuretic effect of nifedipine.

Adult↗
PubMed1987

Repetitive natriuresis and blood pressure. Long-term calcium entry blockade with isradipine.

The long-term effects (3.5 months) of a new calcium entry blocker of the 1-4-dihydropyridine class, isradipine (PN 200-110), on renal hemodynamics and excretional parameters were investigated in 10 essential hypertensive subjects (World Health Organization Classes I and II). Blood pressure and renal vascular resistance fell significantly (p less than 0.001), and a slight increase in glomerular filtration rate and renal plasma flow was seen (p less than 0.05). Output of fluid from the proximal tubules, measured as clearance of lithium and uric acid, increased significantly (p less than 0.01 and p less than 0.05, respectively), and a compensatory increase in absolute reabsorption of sodium beyond the proximal tubular level accompanied by an increase in clearance of potassium was noted. A 40% increase in the resultant clearance of sodium (p less than 0.01) and an increase in diuresis (p less than 0.05) followed the morning dose of isradipine after 3.5 months of treatment. Changes in blood pressure were significantly correlated with changes in absolute proximal reabsorption of sodium (r = 0.81), excretion of sodium (r = -0.64), and diuresis (r = -0.80). Thus, the natriuretic properties of calcium entry blockers may be more important for the long-term antihypertensive effect than the vasodilator effect per se. A model for renal sodium handling following treatment with calcium entry blockers was proposed. Although a causal relationship is not implied, isradipine induced a sustained, repetitive postdose effect on proximal fluid output, net natriuresis, and diuresis, that was intimately related to the long-term blood pressure-regulating response.

Blood Pressure↗
PubMed1987

Acute natriuresis induced by inhibition of proximal tubular reabsorption of sodium and water in hypertensives following acute calcium entry blockade with nifedipine.

To elucidate the renal effects and especially the natriuretic properties of calcium entry blockers, we studied the effect of sublingual nifedipine 20 mg in 16 patients with mild to moderate essential hypertension. The lithium clearance technique was utilized and constant infusion technique was employed to measure glomerular filtration rate (GFR) and renal plasma flow (RPF). Nifedipine induced a significant reduction of systolic and diastolic blood pressure and an increase in heart rate. RPF increased and renal vascular resistance fell significantly, whereas GFR was unchanged. A significant increase in diuresis and in clearance of sodium and lithium was seen. The absolute and fractional proximal reabsorption of sodium and water was reduced. The absolute distal reabsorption increased significantly. The results indicate that the natriuretic action of nifedipine in hypertensives is a proximal tubular event.

Blood Pressure↗
PubMed1987

Acute and long-term effect of antihypertensive treatment on exercise induced microalbuminuria in essential hypertension.

The effects of mild to moderate exercise (450 kpm/min followed by 600 kpm/min, 20 minutes each) on urinary albumin excretion (UAE) were studied with a group of 12 young patients with newly diagnosed essential hypertension. The mean age was 37 years (range 22-45 years) and mean weight 82 kg. During exercise UAE increased significantly from 12.1 microg/min to 16.7 microg/min. Six of the twelve patients were investigated in an acute study with two exercise tests with minimum one week between one of the times metoprolol was given intravenously and the other time was given placebo. In spite of an effective reduction in systolic blood pressure (in mean 23 mmHg during the maximal workload at 600 kpm/min) no significant difference could be seen in UAE. However, a marked decrease in UAE in six patients treated with beta-blocker in a long-term study was seen. Six months after initiating antihypertensive treatment, the baseline systolic blood pressure was reduced by 38 mmHg and UAE by 63%. The maximal exercise induced increased systolic blood pressure level at 600 kpm/min was reduced by 58 mmHg and UAE by 58%. We conclude that UAE both at rest and during exercise may be a sensitive marker of the effectiveness of antihypertensive therapy. UAE is easy to measure and this parameter might be useful in following essential hypertensive patients.

Adult↗