Fluvastatin in primary hypercholesterolemia: efficacy and safety in patients at high risk. An analysis of a clinical trial database.

Patients with primary hypercholesterolemia and established coronary artery disease (CAD) with additional associated risk factors for atherosclerosis are considered for lipid-lowering drug therapy at lower levels of total and/or low-density lipoprotein cholesterol (LDL-C) than are patients with isolated hypercholesterolemia. As regards prevention of cardiovascular morbid events, high-risk patients are expected to receive the most benefit from lipid-lowering treatment. Thus, it is of interest to evaluate the efficacy, safety, and tolerability of the new lipid-lowering agent fluvastatin, a new, wholly synthetic 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, in patients at high risk. A retrospective analysis was based on data from controlled clinical trials in which 1,815 patients were treated with fluvastatin at a daily dose of > or = 20 mg and 783 patients received placebo. Of the fluvastatin-treated patients, 328 (18.1%) had CAD compared with 136 (17.4%) patients taking placebo. Within these groups, 186 fluvastatin patients and 75 placebo patients had at least one of the following additional risk factors: hypertension, obesity, and/or fasting blood glucose levels above the upper limit of normal (ULN). Patients at high risk, as defined above, were compared with patients without CAD or any risk factors (fluvastatin, n = 837; placebo, n = 375). The effect of 40 mg of fluvastatin on LDL and high-density lipoprotein cholesterol (HDL-C), and triglycerides tended to be enhanced in patients at high risk (HR) compared with those at low risk (LR). Changes from baseline in HR patients were: LDL-C, -26.6%; HDL-C, 6.4%; triglycerides, -13%. Changes in LR patients were: LDL-C, -24.8%; HDL-C, 4.4%; triglycerides, -6%. All of these changes were highly significant (0.001 < p < 0.01). No patient in the HR group experienced a confirmed (measured on two consecutive occasions) increase > 3 x ULN in aspartate (ASAT) or alanine (ALAT) aminotransferases, nor any notable increases in creatine kinase > 10 x ULN. The tolerability of fluvastatin, as assessed by analysis of adverse events, was not consistently influenced by concomitant high risk. This exploratory analysis of the efficacy and safety profile of fluvastatin in patients at high risk for atherosclerosis suggests that such treatment is efficacious, safe, and well tolerated. The observed tendency toward an improved efficacy in the high-risk group will need further confirmation using data from prospective studies in such patients.

Efficacy and safety of a combination fluvastatin-bezafibrate treatment for familial hypercholesterolemia: comparative analysis with a fluvastatin-cholestyramine combination.

PURPOSE: Familial hypercholesterolemia (FH) carries a markedly increased risk for coronary artery disease (CAD). Reduction of plasma low-density lipoprotein cholesterol (LDL-C) levels to the normal range may prevent premature atherosclerosis and usually requires a combination of cholesterol-lowering drugs. The major objective of this study is to compare two different drug combinations for the treatment of heterozygous FH. PATIENTS AND METHODS: The current investigation is a short-term, double-blind study comparing the efficacy and safety of fluvastatin when combined with cholestyramine (group 1) or with bezafibrate (group 2) in 38 patients with heterozygous FH. RESULTS: After 6 weeks of combination treatment, in comparison to a drug-free baseline (patients receiving single-blind placebo during the lead-in period of an earlier study, ie, before ever receiving fluvastatin), the combination of 40 mg/d of fluvastatin with 400 mg/d of bezafibrate in group 2 reduced plasma LDL-C levels by 35% as compared with 32% in group 1, and reduced the LDL-C/high-density cholesterol (HDL-C) ratio by 46%, compared to 37% in group 1 (a non-significant difference for both comparisons). When compared to an intermittent 6-week open-label administration of 40 mg fluvastatin monotherapy, the addition of cholestyramine or bezafibrate each reduced LDL-C by an additional 13% (P < 0.01 for both regimens). CONCLUSIONS: Fluvastatin-bezafibrate is superior to a fluvastatin-cholestyramine combination for lowering serum triglycerides and elevating HDL-C serum levels in patients in conjunction with a significant lowering of LDL-C/HDL-C ratios, and may be an effective synergistic therapy for heterozygous FH. No episodes of myositis were seen in this short-term study, a finding that is in agreement with most of the reported studies on statin-fibrate combinations reviewed here.

Fluvastatin in severe hypercholesterolemia: analysis of a clinical trial database.

Many patients with severe primary hypercholesterolemia--low density lipoprotein cholesterol (LDL-C) > 240 mg/dL--have heterozygous familial hypercholesterolemia. In such familial hypercholesterolemic patients, the lipid-lowering efficacy of fluvastatin is related to genetic factors, and it is of interest whether the response to treatment differs from that in patients with more moderate hypercholesterolemia. Thus an exploratory analysis of randomized, controlled clinical trials and their open-label extensions (12-78 weeks), conducted worldwide with fluvastatin > or = 20 mg/day (n = 1810) and placebo (n = 783), assessed whether, apart from the potential differences between familial hypercholesterolemic and nonfamilial hypercholesterolemic patients, the response to 40 mg of fluvastatin is influenced by baseline plasma lipid levels in relation to disease severity. Entry criteria included LDL-C > or = 190 mg/dL with < or = 1 risk factor and no coronary artery disease, or > or = 160 mg/dL with > 1 risk factor or definite coronary artery disease. Of these patients, 591 (33%) given fluvastatin (20-40 mg/day) and 187 (24%) given placebo had severe hypercholesterolemia with baseline LDL-C > 240 mg/dL. In controlled studies, the mean +/- SD duration of exposure was 21.1 +/- 16.1 and 19.4 +/- 15.5 weeks for fluvastatin and placebo, respectively, whereas long-term efficacy was assessed after 55.3 +/- 21.7 weeks (fluvastatin) and 21.1 +/- 12.3 weeks (fluvastatin + cholestyramine, after previous monotherapy). In summary, fluvastatin at 40 mg/day lowered LDL-C by 25-26% from baseline in controlled studies (n = 622), and by 27% in long-term studies (32-33% with fluvastatin + cholestyramine; n = 386), irrespective of severity of cholesterolemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Fluvastatin in familial hypercholesterolemia: a cohort analysis of the response to combination treatment.

A recent randomized, double-blind, double-dummy trial revealed differences in the response of patients with heterozygous familial hypercholesterolemia to combination therapy with the new, wholly synthetic 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor fluvastatin, 20 mg/day and then 40 mg/day, plus the fibric acid analogue bezafibrate, 400 mg/day, vs combination therapy with fluvastatin, 40 mg/day, plus the bile acid sequestrant (resin) cholestyramine, 8 g/day. The main purpose of the present cohort analysis was to determine whether these differences in lipid response were related to imbalances in the patients' prior responses to up to 42 weeks of fluvastatin monotherapy, 20 mg/day, 40 mg/day, and, in some patients, 60 mg/day, in 2 earlier studies. For the present analysis, we identified 18 patients in the fluvastatin plus bezafibrate group (cohort 1) and 16 patients in the fluvastatin plus cholestyramine group (cohort 2) for whom complete dose-response data were available for the full 56-week duration of all 3 studies. Subsets of 7 patients in cohort 1 and 8 patients in cohort 2 had received the 60 mg/day fluvastatin dose during a previous monotherapy study. In cohort 1, low density lipoprotein cholesterol (LDL-C) decreased by 19% with 20 mg/day fluvastatin, by 27% with 40 mg/day fluvastatin, by 31% with 20 mg/day fluvastatin plus bezafibrate, and by 35% with 40 mg/day fluvastatin plus bezafibrate, and the LDL-C/high density lipoprotein cholesterol (HDL-C) ratio had fallen by 46% at the end of combination therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term efficacy with fluvastatin as monotherapy and combined with cholestyramine (a 156-week multicenter study). French-Dutch Fluvastatin Study Group.

Fluvastatin monotherapy up to 40 mg/day over 52 weeks in patients with primary hypercholesterolemia decreased plasma low density lipoprotein cholesterol (LDL-C) by 28%, with varying decreases in plasma triglycerides and increases in high density lipoprotein cholesterol (HDL-C). Patients completing the 52-week study participated in a further trial to assess whether the efficacy of fluvastatin (20-40 mg/day), either as monotherapy or in combination with cholestyramine (CME; 4-16 g/day), taken at least 4 hours prior to fluvastatin, is sustained for up to 3 years. Patients were assessed every 12 weeks on average for safety and efficacy, the latter being calculated as a percent change from baseline of lipids or lipoproteins. During the second year (endpoint up to week 104), 147 patients received monotherapy (estimated mean dose, 30.2 mg/day) and 127 received additional CME (38.1 mg/day fluvastatin plus 10.1 g/day CME). During the third year (endpoint up to week 156), 140 patients received monotherapy (32.5 mg/day) and 67 received additional CME (39.3 mg/day fluvastatin plus 10.3 mg/day CME). Statistically significant reductions in mean total cholesterol and LDL-C and increases in mean HDL-C were achieved in both treatment groups and maintained throughout the study. A significant reduction in triglyceride levels was only observed at the second year endpoint in patients receiving monotherapy (-10.0%).(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy and safety of triple therapy (fluvastatin-bezafibrate-cholestyramine) for severe familial hypercholesterolemia.

Familial hypercholesterolemia carries a markedly increased risk of coronary artery disease. Reduction of plasma low density lipoprotein cholesterol (LDL-C) levels to the normal range may prevent premature atherosclerosis and usually requires a combination of cholesterol-lowering drugs such as 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors plus resins or fibrates. The current, 60-week, open-label investigation involved 22 patients whose plasma LDL-C had not reached the target level for prevention of coronary artery disease in 3 previous studies using fluvastatin alone and in combination with other cholesterol-lowering medications. At the beginning of the current study, patients were stabilized on fluvastatin monotherapy at 40 mg/day. After 6 weeks, the daily treatment changed to a combination of fluvastatin 40 mg/day in the evening and bezafibrate 400 mg/day in the morning. After a further 6 weeks, a lunchtime dose of cholestyramine 8 g/day was added, to form triple cholesterol-lowering therapy. Efficacy was determined by plasma lipid/lipoprotein analysis. Baseline levels were assessed after 4 weeks of placebo treatment, prior to active treatment, in the first fluvastatin study. Safety analyses included liver and renal function tests, creatine phosphokinase levels and blood counts. Compliance was determined by counting the fluvastatin capsules, bezafibrate tablets, and cholestyramine sachets returned by the patients at each visit. The triple-drug combination used in this study was more effective than the double therapy and resulted in stabilization of the LDL-C:high density lipoprotein cholesterol (HDL-C) ratio, at a reduction from baseline ranging from -40.4 to -52.5%.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy and safety of fluvastatin in women with primary hypercholesterolaemia.

Women with primary hypercholesterolaemia are often considered for lipid-lowering drug therapy at a later age than men. With regard to the prevention of cardiovascular morbidity, women can expect to receive the same benefits from lipid-lowering treatment as men. Thus, it is of interest to evaluate the efficacy, safety and tolerability of the new lipid-lowering agent fluvastatin in women. A retrospective analysis was made on the basis of data from controlled clinical trials in which 1815 patients were treated with fluvastatin at a daily dose of > or = 20 mg, and 783 patients received placebo. 782 of the fluvastatin-treated patients (43.1%) and 315 patients on placebo (40.2%) were women. Within these groups, 577 patients (73.8%) treated with fluvastatin and 183 patients receiving placebo (78.4%) were at least 50 years of age. The effect of fluvastatin 40 mg/day on low density lipoprotein (LDL) and high density lipoprotein (HDL) cholesterol was more favourable in women than in men. In women, the change from baseline was -26.7% for LDL cholesterol and 5.3% for HDL cholesterol. In men, the equivalent changes from baseline were -23.8% and 4.0%, respectively. All changes from baseline were highly significant (p < 0.001). Fluvastatin lowered triglycerides to a similar extent in women and men (7.1% vs 6.9%, respectively). More women than men experienced a confirmed increase in aspartate aminotransferase (AST) and alanine aminotransferase (ALT) when receiving fluvastatin.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy and safety of fluvastatin in hypertensive patients. An analysis of a clinical trial database.

The concurrence of hypertension and hypercholesterolemia leads to the clinical need to lower lipids in hypertensive patients. Thus, it is interesting to evaluate the efficacy and safety of fluvastatin, a new 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA)-reductase inhibitor, in such a patient population. A retrospective analysis of the clinical efficacy and safety of fluvastatin was based on the data from 1815 patients who received fluvastatin at daily doses of > or = 20 mg compared with 783 patients taking placebo. The results showed that 332 (18.3%) of the fluvastatin-treated and 124 (15.8%) of the placebo-treated patients were identified as having hypertension. The percentage change from baseline of low-density lipoprotein cholesterol (LDL-C) in hypertensive patients taking fluvastatin at doses of 20 and 40 mg/day was -20% and -26%, respectively (placebo: 1.4%), and did not differ from the response in non-hypertensive patients. Increases in high-density lipoprotein cholesterol (HDL-C) as well as decreases in triglycerides with fluvastatin were not consistently different between hypertensive and non-hypertensive patients. Irrespective of the presence or absence of hypertension, confirmed (measured on two consecutive occasions) increases > three times the upper limit of normal in aspartate aminotransferase (ASAT) and alanine aminotransferase (ALAT) were observed in three (0.2%) and 12 (0.7%) patients, respectively. With placebo, ALAT was increased in two patients (0.2%). The incidence of notable increases more than 10 times the upper limit of normal in creatine kinase was similar with fluvastatin compared with placebo (0.3% in both).(ABSTRACT TRUNCATED AT 250 WORDS)

Safety and tolerability of fluvastatin with concomitant use of antihypertensive agents. An analysis of a clinical trial database.

The coexistence of hypercholesterolemia and hypertension often requires concomitant drug treatments. Thus, it is interesting to evaluate the efficacy, safety, and tolerability of the new lipid-lowering agent fluvastatin, a 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA)-reductase inhibitor, in patients receiving concomitant antihypertensive/cardiovascular drug treatments. A retrospective analysis was based on data from controlled clinical trials in which 1815 patients were treated with fluvastatin and 783 patients received placebo. The daily dose of fluvastatin was > or = 20 mg. At least one of the following drug treatments was taken by 445 of the fluvastatin-treated patients (24.5%) and 181 of those receiving placebo (23.1%): beta-adrenergic-receptor blockers (fluvastatin: n = 182; placebo: n = 84); diuretics (fluvastatin: n = 168; placebo: n = 72); calcium antagonists (fluvastatin: n = 161; placebo: n = 69); and angiotensin-converting enzyme (ACE) inhibitors (fluvastatin: n = 101; placebo: n = 30). The majority of patients received monotherapy with one of the above-mentioned antihypertensive agents (fluvastatin: 69%; placebo: 65%). The efficacy of fluvastatin in modifying low-density lipoprotein (LDL)- and high-density lipoprotein (HDL)-cholesterol and triglyceride levels was not consistently different in patients taking a given antihypertensive compared with the overall group and the patients not taking the antihypertensive agent. In patients taking fluvastatin and antihypertensives, confirmed (measured at two consecutive occasions) increases more than three times the upper limit of normal in aspartate aminotransferase (ASAT) and alanine aminotransferase (ALAT) occurred in only two patients. One case involved the concomitant use of a beta-blocker (ASAT and ALAT) and the other a diuretic (ALAT).(ABSTRACT TRUNCATED AT 250 WORDS)

Changes in blood pressure and heart rate during passive upright tilt upon electrical carotid sinus nerve stimulation.

Electrical carotid sinus nerve stimulation was applied in three normotensive anginal patients and one hypertensive patient during upright tilting. Despite a base-line depressor response to continuous stimulation, orthostatic hypotension was not augmented. In individual patients stimulation slightly enhanced the fall of systolic pressure and delayed the increase of diastolic pressure immediately after tilting. Base-line heart rates and cardio-acceleration upon tilting remained almost uninfluenced by stimulation. It is concluded that a moderately enhanced carotid baroreceptor afferent nerve traffic did not interfere with the regular orthostatic response.

Blood pressure and heart rate changes during physical activity upon heart rate feedback-controlled electrical carotid sinus nerve stimulation.

The effect of feedback-controlled electrical carotid sinus nerve stimulation on changes in blood pressure and heart rate during interventions simulating usual daily activity was studied in four anginal patients. Frequency or amplitude of stimulation was modulated pulse-synchronously and controlled by heart rate. While individual responses differed between both types of modulation, stimulation attenuated predominantly increases in blood pressure during walking and staircase climbing. Heart rate changes remained almost unaffected.

The evolution strategy--a search strategy used in individual optimization of electrical parameters for therapeutic carotid sinus nerve stimulation.

Optimization problems, arising in the search for parameters and/or techniques of functional electrostimulation (FES), disproportionally increase when multiple electrodes, electrode configurations, electrical parameters, and stimulation modes may be applied. When computational or investigational effort precludes systematic studies in FES, we propose to apply and evaluate Rechenberg's evolution strategy, which in technical use and numerical optimization has been valid in comparison to more traditional methods. This strategy implements mutation and selection processes in analogy to biological evolution. The effect of combined multiple input variables on a quality function (Q) is experimentally evaluated. The actual computed value of Q serves as a selection criterion for those input variable combinations which lead Q to approach a target value (maximization), similar to a hill-climbing procedure. In radiofrequency controlled, therapeutic electrical carotid sinus nerve stimulation (CSNS), we varied (mutated) combinations of pulse frequency and pulse amplitude parameters, according to the evolution strategy, in individual patients. CSNS lowers blood pressure and decreases heart rate. Q was computed from blood pressure and heart rate responses to CSNS. The strategy individually optimized electrical parameters to achieve large depressor responses upon CSNS. Although, in contrast to technical usage, only two input variables were investigated, and biomedical experience with the evolution strategy is limited so far, its potential use in other fields of FES, especially when more input variables are to be optimized, is discussed and encouraged.

An implantable carotid sinus baroreflex activating system: surgical technique and short-term outcome from a multi-center feasibility trial for the treatment of resistant hypertension.

OBJECTIVES: To assess perioperative outcomes and blood pressure (BP) responses to an implantable carotid sinus baroreflex activating system being investigated for the treatment of resistant hypertension. METHODS: We report on the first seventeen patients enrolled in a multicenter study. Bilateral perivascular carotid sinus electrodes (CSL) and a pulse generator (IPG) are permanently implanted. Optimal placement of the CSL is determined by intraoperative BP responses to test activations. Acute BP responses were tested postoperatively and during the first four months of follow-up. RESULTS: Prior to implant, BP was 189.6+/-27.5/110.7+/-15.3 mmHg despite stable therapy (5.2+/-1.8 antihypertensive drugs). The mean procedure time was 202+/-43 minutes. No perioperative strokes or deaths occurred. System tests performed 1 or up to 3 days postoperatively resulted in significant (all p < or = 0.0001) mean maximum reduction, with standard deviations and 95% confidence limits for systolic BP, diastolic BP and heart rate of 28+/-22 (17, 39) mmHg, 16+/-11 (10, 22) mmHg and 8+/-4 (6, 11) BPM, respectively. Repeated testing during 3 months of therapeutic electrical activation demonstrated a durable response. CONCLUSIONS: These preliminary data suggest an acceptable safety of the procedure with a low rate of adverse events and support further clinical development of baroreflex activation as a new concept to treat resistant hypertension.

Safety profile of fluvastatin.

Statins are regarded as a well-tolerated class of drugs, particularly when compared with some of the older lipid-modifying agents, which have poor rates of compliance. Despite some early concern, the incidence of lens opacities observed in clinical studies involving statin use is no different from that in a normal ageing population. Similarly, the occurrence of insomnia with lipophilic agents appears to have been overemphasised and is not a clinically significant problem, irrespective of the statin under study. Fluvastatin is the newest representative of this class of agents; it has already been evaluated in thousands of patients who have hyperlipidaemia with and without additional risk factors. In controlled clinical studies, the incidence of the majority of adverse events observed with fluvastatin therapy is no higher than that seen with placebo, with the exception of gastrointestinal disturbances (known to be common to all stains). Nonetheless, the incidence of these effects seen with fluvastatin treatment is noted to be lower than that associated with cholestyramine or fibrate use. Elevations in levels of liver transaminases (aspartate aminotransferase and alanine aminotransferase) have been reported with fluvastatin therapy but have led to discontinuation of treatment with the same frequency as with placebo. Elevations in creatine kinase levels as a cause of discontinuing fluvastatin are not more frequent than with placebo. Myopathy and rhabdomyolysis have not been reported with fluvastatin therapy, and myalgia does not occur more frequently than with placebo. In terms of drug interactions, fluvastatin does not interfere with the efficacy of antihypertensive agents. In controlled clinical trials, the overall reported discontinuation rate due to adverse events noted with fluvastatin therapy is 3.3%, which is not significantly distingushable from the rate associated with placebo (3.5%)2.

Treatment of dyslipidaemias with fluvastatin.

In many patients with primary hyperlipidaemia the statins have become the drugs of choice when diet alone has failed. Despite the availability of different potencies of the statins, the dosages prescribed in most countries appear to be aimed at producing a reduction in levels of low-density lipoprotein cholesterol (LDL-C) of about 25%. Fluvastatin is the newest member of this class of agent and the first completely synthetic compound. In dose-finding studies, fluvastatin has produced statistically significant (P < 0.001) reductions in LDL-C levels when used in dosages of 20 mg (21%) and 40 mg (27.4%), thus placing it within the range generally required of other statins; additional studies have shown that the efficacy of fluvastatin is unaffected by gender and age. Moreover, fluvastatin produces the maximum reduction in LDL-C levels within 6 weeks and maintains this efficacy during long-term treatment (LDL-C levels have been reported to fall by 27.4% over 2 years with fluvastatin 40 mg/day). In high-risk patients the LDL-C-lowering effect of fluvastatin 40 mg/day is maintained when compared with low-risk patients (26.6% vs 24.8%). A similar pattern has been observed in hypertensive patients, irrespective of the antihypertensive agent used to control blood pressure. Fluvastatin has been found to produce better LDL-C-lowering effects than bezafibrate and come instances has exhibited an advantage over other statins. In addition to lowering LDL-C levels by the required amount, 20 and 40 mg (the equivalent of pravastatin 20 mg) dosages of fluvastatin significantly reduce levels of total cholesterol and triglycerides and increase high-density lipoprotein cholesterol levels.

Treatment of dyslipidaemias with fluvastatin.

In many patients with primary hyperlipidaemia the statins have become the drugs of choice when diet alone has failed. The usual dosages of statins prescribed in most countries appear to be aimed at producing a reduction in levels of low-density lipoprotein cholesterol (LDL-C) of about 25%. Fluvastatin is the newest member of this class of agent and the first completely synthetic compound. In dose-finding studies, fluvastatin has produced statistically significant (P < 0.001) reductions in LDL-C levels when used in dosages of 20 mg (21%) and 40 mg (27.4%), thus placing it within the range generally expected with usual dosages of other statins; additional studies have shown that the efficacy of fluvastatin is unaffected by gender and age. Moreover, fluvastatin produces the maximum reduction in LDL-C levels within 6 weeks and maintains this efficacy during long-term treatment (LDL-C levels have been reported to fall by 27.4% over 2 years with fluvastatin 40 mg/day). In high-risk patients the LDL-C-lowering effect of fluvastatin 40 mg/day is maintained when compared with low-risk patients (26.6% vs 24.8%). A similar pattern has been observed in hypertensive patients, irrespective of the antihypertensive agent used to control blood pressure. Fluvastatin has been found to produce better LDL-C-lowering effects than bezafibrate. In addition to lowering LDL-C levels by the required amount, 20 and 40 mg (the equivalent of pravastatin 20 mg) dosages of fluvastatin significantly reduce levels of total cholesterol and triglycerides and increase high-density lipoprotein cholesterol levels.

Safety profile of fluvastatin.

Statins are regarded as a well-tolerated class of drugs, particularly when compared with some of the older lipid-modifying agents, which have poor rates of compliance. Despite some early concern, the incidence of lens opacities observed in clinical studies involving statin use is no different from that in a normal ageing population. Similarly, the occurrence of insomnia with lipophilic agents appears to have been overemphasised and is not a clinically significant problem, irrespective of the statin under study. Fluvastatin is the newest representative of this class of agents; it has already been evaluated in thousands of patients who have hyperlipidaemia with and without additional risk factors. In controlled clinical studies, the incidence of the majority of adverse events observed with fluvastatin therapy is no higher than that seen with placebo, with the exception of gastrointestinal disturbances (known to be common to all stains). Nonetheless, the incidence of these effects seen with fluvastatin treatment is noted to be lower than that associated with cholestyramine or fibrate use. Elevations in levels of liver transaminases (aspartate aminotransferase and alanine aminotransferase) have been reported with fluvastatin therapy but have led to discontinuation of treatment with the same frequency as with placebo. Elevations in creatine kinase levels as a cause of discontinuing fluvastatin are not more frequent than with placebo. Drug-related myopathy and rhabdomyolysis have not been reported with fluvastatin therapy, and myalgia does not occur more frequently than with placebo. In terms of drug interactions, fluvastatin does not interfere with the efficacy of antihypertensive agents. In controlled clinical trials, the overall reported discontinuation rate due to adverse events noted with fluvastatin therapy is not significantly distinguishable from the rate associated with placebo.

Plasma renin activity during hypotensive responses to electrical stimulation carotid sinus nerves in conscious dogs.

1. The interaction of electrical stimulation of the carotid sinus nerves (carotid sinus nerve stimulation, CSNS) with mechanisms of renin release was studied in conscious and unrestrained resting beagle dogs receiving a standardized diet (sodium intake, 4.5 mmol/kg bodyweight (bw); water intake, 91 mL/kg bw). 2. By CSNS, mean arterial blood pressure (MAP) was lowered for periods of 20 min to levels between 101 +/- 4 and 56 +/- 5 mmHg. 3. In another group of conscious dogs, renal perfusion pressure (RPP) was lowered to 95 +/- 4 mmHg for periods of 20 min by partial suprarenal aortic occlusion in order to assess the influence of a reduced RPP on plasma renin activity (PRA) without concomitant CSNS. 4. During CSNS, PRA increased markedly (> 100%) only when MAP was reduced below 75 mmHg. 5. With aortic constriction and an RPP of 95 mmHg, the increase in PRA was 955%, which is more than three-fold higher than the increase in PRA during CSNS at MAP levels < 65 mmHg (314%). 6. The observed responses indirectly support the hypothesis that basal activity in efferent renal nerve discharge is present even at rest and can be inhibited by CSNS, and furthermore suggests that CSNS attenuated the pressure-dependent renin release.

Cardiovascular responses to time delays of electrocardiogram-coupled electrical stimulation of carotid sinus nerves in dogs.

In search of improved patterns for electrical stimulation of the carotid sinus nerves (CSNs), which is applied therapeutically in patients with previous therapy refractory hypertension or angina pectoris, the timing of stimulation trains within the cardiac cycle was investigated in anesthetized dogs. Blood pressure responses and prolongations of heart beat intervals upon CSNs were analyzed. Electrocardiogram (ECG)-coupled trains of electrical stimuli were applied to bilateral intact CSNs. Pulses of 1 ms duration and the maximal (5-10 V) and 50% maximal stimulus amplitude were applied. The onset of stimulation trains (150 ms long, 15 impulses/train) was delayed from ECG-R-wave synchronous periods in units of 30 ms to maximally 150 ms. The timing of stimulus trains within the cardiac cycle did not influence the responses. Heart rate and blood pressure reductions upon CSNs were entirely dependent on the amplitudes of stimuli. In conclusion, a phase-dependency of such responses to CSNs, supposedly due to coincidence of electrically induced carotid sinus nerve activity with endogenous signals centrally converging from other cardiovascular afferents, could not be supported, using such stimulation trains. The observed responses did not show the known phase-dependency of sensitivity of the sino-atrial node to changes in effernt vagal activity. In experimental and therapeutic electrical CSNs (baropacing) for obtaining stronger cardiovascular responses with similar parameters, a preferential timing of stimuli relative to the cardiac cycle cannot be recommended.

Search for optimal frequencies and amplitudes of therapeutic electrical carotid sinus nerve stimulation by application of the evolution strategy.

In humans, electrical, bipolar, bilateral carotid sinus nerve stimulation (CSNS; impulse duration 0.35 ms) was applied, using frequencies between 10 and 110 Hz and voltages between individual thresholds and maximal amplitudes of stimulation. Ten anginal patients and two hypertensive patients were studied at an interval of up to 12 years after implantation of electrodes and a radiofrequency receiver for chronic therapeutic CSNS. In search of combinations of frequency and voltage of CSNS, eliciting largest ("optimal") depressor responses of blood pressure and heart rate in the individual patient, Rechenberg's evolution strategy was applied. This strategy simulates mutation and selection of biological evolution. In each patient and on each test stimulation, a value of quality was computed from actual heart rate and blood pressure values as a selection criterion for the strategy. Either responses to uninterrupted CSNS were investigated, while stimulation parameters were adjusted every 3 min, according to the strategy, or responses to 3 min of CSNS after a change in stimulation parameters were compared to intercalated 3-min control periods. In each patient, one or more combined settings of frequency and voltage elicited "optimal" responses. In principle, "optimal" CSNS frequencies ranged between 35 and 105 Hz with large interindividual differences. Due to chronic implantation of electrodes and technical features of radiofrequency transmitted stimulation energy, interindividually different voltages led to an optimal response to CSNS. Also according to the present results, the frequency of CSNS has to be determined individually. It is concluded that the evolution strategy was applied successfully, because voltage and frequency settings leading to "optimal" responses were found within 90-180 min, whereas intraindividual systematic investigations would not be feasible due to their necessarily very long duration. So far, only short-term responses have been evaluated. A broader use of the strategy in other applications is encouraged, as for example in pacemaker optimization and especially in functional electrostimulation.