Prevention of cardiovascular events in end-stage renal disease: results of a randomized trial of fosinopril and implications for future studies

Cardiovascular events (CVEs) are the leading cause of death in chronic hemodialysis patients. Results of trials in non-end-stage renal disease (ESRD) patients cannot be extrapolated to patients with ESRD. It is critical to test cardiovascular therapies in these high-risk patients who are usually excluded from major cardiovascular trials. The study objective was to evaluate the effect of fosinopril on CVEs in patients with ESRD. Eligible patients were randomized to fosinopril 5 mg titrated to 20 mg daily (n=196) or placebo (n=201) plus conventional therapy for 24 months. The primary end point was combined fatal and nonfatal first major CVEs (cardiovascular death, resuscitated death, nonfatal stroke, heart failure, myocardial infarction, or revascularization). No significant benefit for fosinopril was observed in the intent to treat analysis (n=397) after adjusting for independent predictors of CVEs (RR=0.93, 95% confidence interval (CI) 0.68-1.26, P=0.35). The per protocol secondary supportive analysis (n=380) found a trend towards benefit for fosinopril (adjusted RR=0.79 (95% CI 0.59-1.1, P=0.099)). In the patients who were hypertensive at baseline, systolic and diastolic blood pressures were significantly decreased in the fosinopril as compared to the placebo group. After adjustment for risk factors, trends were observed suggesting fosinopril may be associated with a lower risk of CVEs. These trends may have become statistically significant had the sample size been larger, and these findings warrant further study.

Myocardial collagen turnover in normotensive obese patients: relation to insulin resistance

OBJECTIVES

The present study was undertaken to assess the differential impact of insulin resistance, leptin and body composition on myocardial mass and serum markers of cardiac fibrosis in obese subjects, within a small range of elevated BMI (30-40 kg/m(2)), without pulmonary disease, cardiovascular disease, hypertension, cardiac hypertrophy or other cardiovascular disease.

BACKGROUND

Obesity is an independent predictor of left ventricular mass (LVM) and is associated with disturbances in cardiac structure. The extent of the interstitial fibrosis in obese patients is not known, especially in the absence of cardiac hypertrophy.

METHODS AND RESULTS

We included 160 obese subjects. The LVM was obtained using the Devereux formula. Body composition was estimated from a total body scan. Insulin sensitivity was assessed by homeostasis model assessment (HOMA), and cardiac collagen turnover by measurement of procollagen type III aminopeptide (PIIINP). PIIINP was correlated to the E/A ratio (r=0.24; P=0.012), a marker of ventricular function. PIIINP was independently correlated with glucose concentration (r=0.27; P=0.004), indexes of insulin resistance (HOMA (r=0.27; P=0.003), insulin (r=0.24; P=0.008)), and parameters associated with the insulin-resistance syndrome (HDL-cholesterol r=-0.27; P=0.004) and fat trunk/fat leg ratio (r=0.24; P=0.053)). The variable most correlated with PIIINP was HDL-cholesterol, followed by HOMA (r (2)=0.13). When HOMA was substituted for blood glucose concentration and insulinemia (Model 2), HDL-cholesterol was strongly related to lower PIIINP levels, followed by higher glucose concentration (r (2)=0.21). Regression analyses showed that LVM had the strongest independent positive correlation with fat-free mass (FFM) (r=0.39; P=0.0002), followed by systolic blood pressure (r=0.19; P=0.034). Neither adipose mass nor height independently added information to multivariate models. The ratio leptin/fat mass was correlated with LVM (r=-0.27; P=0.004), but not independently of the FFM. Markers for fibrosis were not significantly correlated with LVM. As a result, FFM was the most predictive factor of LVM in obese subjects.

CONCLUSION

We found that serum levels of markers of cardiac collagen synthesis were significantly associated with insulin resistance in normotensive, nondiabetic obese subjects, and not related to the LVM. As a result, PIIINP could be a very early marker of ventricular dysfunction in these patients. Furthermore, we suggest that, for better detection of left ventricle hypertrophy in obese subjects, LVM should be indexed to FFM rather than to body surface area, or height.

Initial infarct size predicts subsequent cardiac remodeling in the rat infarct model: an in vivo serial pinhole gated SPECT study

The rat infarct model is widely used to study left ventricular (LV) remodeling, a main cause of heart failure characterized by progressive LV dilatation. Using pinhole collimators and advances in data processing, gated SPECT was recently adapted to image the rat heart. The aim of this study was to assess this new imaging technique for predicting and quantifying variable LV remodeling from the rat infarct model.

METHODS

Pinhole 99mTc-sestamibi gated SPECT was validated for determining LV volume and identifying the necrotic and nonviable LV segments (<50% of 99mTc-sestamibi uptake) in rats, and it was applied to monitor rat LV function from 48 h to 12 wk after occlusion of the left anterior descending coronary artery (LAD) (n = 20) or sham operation (n = 9).

RESULTS

In LAD-occluded rats, 48-h SPECT necrosis was large (> or =30% LV) in 6, limited (<30% LV) in 6, and undetectable in 8. End-diastolic volume of LAD-occluded rats was equivalent to that of sham-operated rats at 48 h (320 +/- 84 microL vs. 293 +/- 48 microL; not significant) but became higher at 12 wk (501 +/- 191 microL vs. 343 +/- 46 microL; P = 0.01). The follow-up increase in end-diastolic volume, which reflects the remodeling process, was closely related to the initial extent of necrosis revealed by the SPECT images (P < 0.001; R2= 0.85). This increase was limited in sham-operated rats (50 +/- 15 microL) and in the LAD-occluded rats with undetectable necrosis (55 +/- 35 microL) but it was around 3- and 7-fold higher in the LAD-occluded rats with limited (165 +/- 57 microL) and large (366 +/- 113 microL) necrosis, respectively.

CONCLUSION

The variable LV remodeling documented after coronary occlusion in rats closely relates to the variable extent of necrosis provided by this model. Pinhole gated SPECT allows this remodeling to be predicted and quantified and, hence, constitutes an original tool for the experiments scheduled on the rat infarct model.

Changes in First-Pass Interstitial Kinetics of DTPA in Myocardium Submitted to Low-Flow Ischemia

OBJECTIVES

This study aimed to determine the changes during ischemia in the myocardial first-pass kinetics of DTPA, an extracellular tracer that is currently used for assessing myocardial perfusion with magnetic resonance imaging (Magnevist).

MATERIALS AND METHODS

Using an indicator-dilution technique, first-pass kinetics of DTPA were compared between normoxia (n=11) and low-flow ischemia (n=11) in isolated rabbit hearts perfused with red blood cell-enhanced perfusate.

RESULTS

There was no difference between ischemia and normoxia in the interstitial extraction and clearance rates of DTPA. Interstitial distribution volume of DTPA was, however, lower in ischemia than in normoxia (in percent of myocardial volume: 15+/-11% vs 25+/-11%, P=0.02) as a result of a relationship with coronary flow (P<0.001).

CONCLUSIONS

During low-flow myocardial ischemia, DTPA kinetics are unchanged, except for the interstitial distribution volume that is decreased, presumably because of the shrinkage of extracellular fluid. These kinetic properties are favorable for detecting myocardial ischemia at rest with magnetic resonance imaging.

Educational governance for the regulation of industry sponsored continuing medical education in interventional and device based therapies

The relationship between industry and clinicians in educational programmes needs to be regulated. Industry may be best placed to deliver educational programmes in "craft" related specialties and particularly in areas where device implantation/technology based therapy has a major clinical role. The authors supervise industry sponsored clinical teaching at a purpose built independent teaching facility, and have developed the concept of educational governance to regulate their relationship with their industry sponsor and that concept is presented.

Managing hypertension: a question of STRATHE

Current international guidelines recommend the use of therapeutic strategies with proven efficacy in the management of hypertension to achieve a target blood pressure of < 140/90 mmHg. After lifestyle intervention, they endorse three different management strategies: (i) first-line use of a low-dose combination of two agents from different antihypertensive classes, with the option of doubling the dose of the combination; (ii) use of a sequential monotherapy strategy, initiating with one antihypertensive to be replaced by another one from a different class, if necessary; and (iii) a stepped care strategy, initiating with one antihypertensive, and increasing the dose or adding another agent from a different class, if necessary. The objective of the STRAtegies of Treatment in Hypertension: Evaluation (STRATHE) study was to compare the efficacy and tolerability of these three treatment strategies in patients with uncomplicated essential hypertension (n = 533). In all, 62% of the patients in the low-dose combination group were normalised (< 140/90 mmHg), compared with 49% of the sequential monotherapy group (P = 0.01) and 47% of the stepped-care group (P = 0.005). The percentage of patients achieving normalisation without experiencing drug-related adverse events was also significantly higher in the low-dose combination group (56%) than in the sequential monotherapy (42%, P = 0.001) and stepped-care groups (42%, P = 0.004), consistent with the observation that the reduced dosage of the antihypertensive agents in such preparations translates into improved acceptability. The results of STRATHE provide further support for an antihypertensive management strategy involving the low-dose combination of perindopril (2 mg) and indapamide (0.625 mg).

Comparison of different therapeutic strategies in hypertension

OBJECTIVE

To compare the efficacy and the tolerability of three different strategies in the treatment of hypertension (low-dose combination, sequential monotherapy and stepped-care).

DESIGN

Hypertensive patients were randomized to a 9-month treatment with the aim to lower blood pressure below 140/90 mmHg. Treatment adjustments were allowed at months 3 and 6. The study was discontinued for patients with normal blood pressure at month 6. In the 'low-dose combination' group, perindopril (2 mg) and indapamide (0.625 mg) were first administered with the possibility to increase the doses in two steps up to respectively, 4 and 1.25 mg. In the 'sequential monotherapy' group, the treatment was initiated with atenolol (50 mg), replaced if necessary by losartan (50 mg), and then by amlodipine (5 mg). In the 'stepped-care' group, valsartan, was given first at a 40 mg dose, then at a 80 mg dose, to be co-administered finally if needed with hydrochlorothiazide, 12.5 mg. All study tablets were encapsulated to conceal their identity and had to be taken once a day.

PATIENTS

Patients with uncomplicated essential hypertension were recruited (n = 180 in the 'low-dose combination' group, n = 176 in the 'sequential monotherapy' group and n = 177 in the 'stepped-care' group).

RESULTS

The percentage of patients having achieved the target blood pressure was significantly greater in the 'low-dose combination' group (62%) than in the 'sequential monotherapy' (49%, P = 0.02) and the 'stepped-care' group (47%, P = 0.005). The percentage of patients having normalized their blood pressure without experiencing drug-related adverse events was also significantly higher in the 'low-dose combination' group (56%) than in the 'sequential monotherapy' (42%, P = 0.002) and the 'stepped-care' group (42%, P = 0.004).

CONCLUSIONS

A first line management of hypertension based on a low-dose combination of perindopril and indapamide allows the normalization of blood pressure in significantly more patients than a 'sequential monotherapy' strategy involving atenolol, losartan and amlodipine, and a 'stepped-care' strategy involving valsartan and hydrochlorothiazide. These better blood pressure results were not obtained at the expense of a worsening of tolerability.

Pharmacogenomics in cardiovascular clinical trials

Genomics - having quickly emerged as the central discipline in basic science and biomedical research - is poised to take the center stage in clinical medicine as well over the next few decades. Although there is no specific regulatory guideline on the application of pharmacogenetics to drug development, some recommendations are already included in several published guidelines on drug development. The patients more likely to provide the most valuable information on the specific contribution of a given gene or its variant are those who fail to respond to a drug ('therapeutic failures') and those who develop toxicity to the drug. However, before drawing definite conclusions on subgroups following pharmacogenomic analyses, one must be aware of disease classification, data collection, and how much is known about the disease process. It seems reasonable to collect genomic DNA from all patients enrolled in clinical drug trials (along with appropriate consent to permit pharmacogenetic studies) for the purpose of post hoc analyses. One exception to post hoc genomic analysis is when patients with a specific genotype are excluded from randomization into a clinical trial. Physicians will need to understand the concept of genetic variability, its interactions with the environment (e.g. drug-drug or drug-disease interactions), and its implication for patient care.

Mannheim intima-media thickness consensus

Intima-media thickness (IMT) is increasingly used in clinical trials as a surrogate end point for determining the success of interventions that lower risk factors for atherosclerosis. The necessity for unified criteria to distinguish early atherosclerotic plaque formation from thickening of IMT and to standardize IMT measurements is addressed in this consensus statement. Plaque is defined as a focal structure that encroaches into the arterial lumen of at least 0.5 mm or 50% of the surrounding IMT value or demonstrates a thickness of > or =1.5 mm as measured from the media-adventitia interface to the intima-lumen interface. Standard use of IMT measurements is recommended in all epidemiological and interventional trials dealing with vascular diseases to improve characterization of the population investigated. The consensus concludes that there is no need to 'treat IMT values' nor to monitor IMT values in individual patients apart from few exceptions. Although IMT has been suggested to represent an important risk marker, it does not fulfill the characteristics of an accepted risk factor. Standardized methods recommended in this consensus statement will foster homogenous data collection and analysis. This will help to improve the power of studies incorporating IMT measurements and to facilitate the merging of large databases for meta-analyses.

Exercise release of cardiac natriuretic peptides is markedly enhanced when patients with coronary artery disease are treated medically by beta-blockers

OBJECTIVES

This study sought to identify determinants of the exercise rise in plasma levels of cardiac natriuretic peptides (NPs) in patients with coronary artery disease (CAD).

BACKGROUND

During stress, there is a variable rise in the plasma level of NPs, but this rise frequently reaches levels that are known to lower the cardiac load and that thus might be beneficial to CAD patients.

METHODS

Plasma venous concentrations of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) were determined at rest and peak exercise in 104 patients with chronic CAD who were referred to exercise thallium-201 ((201)Tl) single-photon emission computed tomography (SPECT) and radionuclide angiography.

RESULTS

The extent of scarred myocardium by (201)Tl-SPECT and patient age were the best independent predictors of NP concentrations at rest, but also of increases in NP concentration during exercise (all p < 0.001). Moreover, beta-blocking treatment was an additional and strong independent predictor of the increase in NP concentrations at exercise (p < 0.001 for ANP; p = 0.001 for BNP). On average, exercise increases in NP concentrations were more than twice as high in patients with (n = 55) than in those without (n = 49) beta-blocker treatment (ANP: +49 +/- 63 vs. +22 +/- 25 ng/l, p = 0.01; BNP: +24 +/- 5 vs. +11 +/- 15 ng/l, p = 0.04), whereas NP concentrations at rest were equivalent in the two groups (ANP: 34 +/- 34 vs. 30 +/- 33 ng/l, p = NS; BNP: 85 +/- 152 vs. 57 +/- 101 ng/l, p = NS).

CONCLUSIONS

Patients with chronic CAD exhibit much higher exercise releases of ANP and BNP when they are treated with beta-blockers. This enhanced secretion of potent vasodilating and natriuretic agents constitutes an original therapeutic mechanism for further protecting diseased hearts against stress.

[Angiotensin-converting enzyme inhibitors in congestive heart failure: clinical practice guidelines]

Angiotensin-converting enzyme (ACE) inhibitors are, at present, the cornerstone of therapy for congestive heart failure. Nevertheless, international literature and regional data have reported their underutilisation in the practice of cardiology. Despite the abundance of consensus conferences, none deal specifically with a therapeutic strategy using ACE inhibitors. In this context, clinical practice guidelines on the management of systolic heart failure with ACE inhibitors have been drafted in Lorraine by hospital cardiologists. The guidelines were formulated using a standardised procedure, combining a literature analysis and the opinions of experts. Seventeen guidelines were finally adopted, under four headings: indications and contraindications for ACE inhibitors; dosages and approaches to treatment monitoring; the management of adverse effects; and contraindications for concomitant therapy. The drafting of the clinical practice guidelines is the first step in a quality improvement programme, initiated in 1999 in the cardiology wards of the region.

Residual exercise SPECT ischemia on treatment is a main determinant of outcome in patients with coronary artery disease treated medically at long-term with beta-blockers

BACKGROUND

Beta-blockers are potent anti-ischemic medications, able to improve prognosis in patients with coronary artery disease (CAD). However, it is not known whether beta-blockers have the same beneficial prognostic effect when residual ischemia persists on treatment.

METHODS AND RESULTS

The prognostic impact of exercise single photon emission computed tomography (SPECT) ischemia was analyzed in 442 patients with chronic CAD, who were treated with beta-blockers and who were referred to exercise thallium 201 SPECT, while they were receiving their daily-life medications. Ischemic and viable myocardium was documented on Tl-201 SPECT in 190 patients (43%), of whom only 23% had angina and only 26% had positive exercise testing results. During a follow-up of 3.8 +/- 1.7 years, 36 patients died and survival curves were progressively divergent between patients with and those without ischemic and viable myocardium: at 5 years, the respective survival rates were 81% +/- 4% and 94% +/- 2% (P =.004). By multivariate analysis, the best independent predictors of death were large extent of necrosis (>25% of left ventricle on Tl-201 SPECT, P <.001) and ischemic and viable myocardium (P =.001).

CONCLUSIONS

In the CAD patients treated on a long-term basis with beta-blockers, survival is strongly influenced by persistent exercise SPECT ischemia on treatment. Therefore exercise SPECT on treatment could be a useful tool for selecting those who might benefit from additional anti-ischemic therapeutic interventions.

Evaluation de différentes modalités de traitement de l’hypertension artérielle : association faiblement dosée perindopril/indapamide versus traitement séquentiel ou traitement pas à pas

A randomised double-blind comparison of three treatment strategies in 533 patients with mild-to-moderate hypertension over 6-9 months. The low-dose perindopril/indapamide (PER/IND) combination (2 mg and 0.625 mg, respectively) daily resulted in a significantly better blood pressure control and systolic blood pressure decrease. In addition, the low-dose PER/IND combination showed superior efficacy/safety criteria than the sequential strategy of atenolol (50 mg) then losartan (50 mg) then amlodipine (5 mg), and the step-by-step strategy of valsartan (40 mg then 80 mg then 80 mg plus hydrochlorothiazide 12.5 mg).

Information du public sur les essais cliniques et la recherche

Be it to restore the confused image of clinical research in relation to the lay public, or to develop new ways of accruing healthy volunteers or patients for clinical trials, there is a need to draft some guidance on how best to provide information on research. Although the French legal and regulatory armamentarium in this area is essentially liberal, there is currently little-justified reluctance among study sponsors to advertise publicly. A group of academic and pharmaceutical industry researchers, assembled for a workshop, together with regulators, journalists, representatives from ethics committees, social security, patient and health consumer groups and other French institutional bodies, has suggested the following series of recommendations: there is no need for additional legal or regulatory constraints; sponsors should be aware of and make use of direct public information on trials; a 'good practice charter' on public communication about clinical trials should be developed; all professionals should be involved in this communication platform; communication in the patient's immediate vicinity should be preferred (primary-care physician, local press); clinical databases and websites accessible to professionals, but also to patients and non-professionals, should be developed; genuine instruction on clinical trials for physicians and health professionals unfamiliar with such trials should be developed and disseminated; media groups should receive at least some training in the fundamentals of clinical research.

[Treatment with lepirudin in heparin-induced thrombocytopenia. A case report]

We report the case of a 71 old woman presenting a bilateral massive pulmonary embolism with intraventricular right thrombus complicating heparin induced thrombocytopenia (HIT) persistent after one month of conventional anticoagulant processing. We underline the effectiveness of lepirudin (Refludan) in the curative processing of pulmonary embolism allowing here to avoid a complex surgical thromboembolectomy. We evoke the place of this molecule in the curative therapeutic strategy of HIT with thrombotic phenomena.