Beneficial effects of treatment with transglutaminase inhibitor cystamine on the severity of inflammation in a rat model of inflammatory bowel disease.

Inflammatory bowel disease (IBD) represents a socially and clinically relevant disorder, characterized by intestinal chronic inflammation. Cystamine (CysN) is a multipotent molecule with healthy effects and, moreover, it is an inhibitor of transglutaminases (TGs), including the TG type 2 (TG2), an enzyme with pleiotropic functions, involved in different pathways of inflammation and central in the pathogenesis of some human disorders as the IBD. Our aim was to evaluate the effect of CysN in an IBD rat model. A total of 30 rats were divided into 4 groups: controls without treatment (CTR; n=7); receiving the 2,4,6-trinitrobenzene sulfonic acid enema (TNBS group; n=8); treated with TNBS enema plus oral CysN (TNBS-CysN group; n=8); treated with CysN (CysN group; n=7). After killing, bowel inflammation was evaluated applying specific scores. TG activity, TG2 and isopeptide bond immunohistochemical expression, and tumor necrosis factor-α (TNF-α) were evaluated in the colonic tissue, such as interleukin-6 (IL-6) serological levels (ELISA). TG2 was also evaluated on the luminal side of the colon by immunoautoradiography. Colonic samples from IBD patients were compared with animal results. TNBS-CysN group developed a less severe colitis compared with the TNBS group (macroscopic score 0.43±0.78 vs 3.28±0.95, microscopic score 6.62±12.01 vs 19.25±6.04, P<0.05, respectively) associated with a decrease of TG activity, TG2 and isopeptide bond immunohistochemical expression, TNF-α and IL-6 levels. No statistically significant differences were found between CysN and CTR groups. The colonic immunolocalization of TG2 was comparable in humans affected by IBD and TNBS-administered animals. This is the first demonstration that treatment with a CysN has an anti-inflammatory effect, reducing severity of colitis in a rat model. CysN could be tested as a possible treatment or co-treatment in IBD therapeutic trials.

Isolation and culture of fibroblasts from endoscopic duodenal biopsies of celiac patients.

BACKGROUND: Fibroblasts are actually considered pivotal in inflammation and tissue remodelling process and for these reasons they are involved in the pathogenesis of autoimmune disorders such as celiac disease. Investigations to define the role of fibroblasts in celiac diseases are obstructed by the absence of specific models. Our objective is to isolate and culture primary fibroblasts from endoscopic duodenal biopsies of celiac and non-celiac subjects, to analyze their growth patterns and the morphometric characteristics. METHODS: 60 duodenal bioptic specimens from 20 celiac patients and 114 from 38 non-celiac subjects were mechanically chopped and enzymatically digested in order to obtain primary cell cultures. Growth patterns, karyotype (Q-banding analysis), expression of typing proteins (fibroblast surface protein and cytokeratin 20) and morphometric parameters (diameters and their ratio, perimeter, area and perimeter/area ratio at computerised image analysis) were investigated on cultured cells. RESULTS: Primary cells were successfully cultured in 78% of the collected duodenal biopsies. Cultured cells, expressing the fibroblast surface protein, were negative for cytokeratine 20 and maintained a normal kariotype. Cells grew slowly without differences between the celiac and the non celiac group. Morphometric analysis of celiac fibroblasts revealed significantly increased dimensions, with a preserved diameters ratio, and a reduced perimeter/area ratio. CONCLUSION: For the first time this study demonstrates the feasibility of culturing primary fibroblast cell from endoscopic duodenal biopsies in celiac and non-celiac subjects, opening a new window of opportunity in studies intended to establish the role of fibroblasts as a possible partaker in the pathogenesis of the celiac mucosal damage.

Potential advantages of cell administration on the inflammatory response compared to standard ACE inhibitor treatment in experimental myocardial infarction.

BACKGROUND: Bone Marrow (BM) progenitor cells can target the site of myocardial injury, contributing to tissue repair by neovascolarization and/or by a possible direct paracrine effect on the inflammatory cascade. Angiotensin Converting Enzyme inhibitors (ACE-I) are effective in reducing mortality and preventing left ventricular (LV) function deterioration after myocardial infarction. METHODS: We investigated the short term effects of BM mononuclear cells (BMMNCs) therapy on the pro-inflammatory cytokines (pro-CKs) and on LV remodelling and compared these effects over a standard ACE-I therapy in a rat model of myocardial cryodamage. Forty two adult inbread Fisher-F344 rats were randomized into three groups: untreated (UT; n = 12), pharmacological therapy (ACE-I; n = 14, receiving quinapril), and cellular therapy (BMMNCs; n = 16, receiving BMMNCs infusion). Rats underwent to a standard echocardiogram in the acute setting and 14 days after the damage, before the sacrifice. Pro-CKs analysis (interleukin (IL)1beta, IL-6, tumor necrosis factor (TNF)alpha was performed (multiplex proteome arrays) on blood samples obtained by direct aorta puncture before the sacrifice; a control group of 6 rats was considered as reference. RESULTS: Concerning the extension of the infarcted area as well as the LV dimensions, no differences were observed among the animal groups; treated rats had lower left atrial diameters and higher indexes of LV function. Pro-Cks were increased in infarcted-UT rats if compared with controls, and significantly reduced by BMMNCs and ACE-I ; TNFalpha inversely correlated with LV fractional shortening. CONCLUSION: After myocardial infarction, both BMMNCs and ACE-I reduce the pattern of pro-Ck response, probably contributing to prevent the deterioration of LV function observed in UT rats.

Effects of simulated altitude (normobaric hypoxia) on cardiorespiratory parameters and circulating endothelial precursors in healthy subjects.

BACKGROUND: Circulating Endothelial Precursors (PB-EPCs) are involved in the maintenance of the endothelial compartment being promptly mobilized after injuries of the vascular endothelium, but the effects of a brief normobaric hypoxia on PB-EPCs in healthy subjects are scarcely studied. METHODS: Clinical and molecular parameters were investigated in healthy subjects (n = 8) in basal conditions (T0) and after 1 h of normobaric hypoxia (T1), with Inspiratory Fraction of Oxygen set at 11.2% simulating 4850 mt of altitude. Blood samples were obtained at T0 and T1, as well as 7 days after hypoxia (T2). RESULTS: In all studied subjects we observed a prompt and significant increase in PB-EPCs, with a return to basal value at T2. The induction of hypoxia was confirmed by Alveolar Oxygen Partial Pressure (PAO2) and Spot Oxygen Saturation decreases. Heart rate increased, but arterial pressure and respiratory response were unaffected. The change in PB-EPCs percent from T0 to T1 was inversely related to PAO2 at T1. Rapid (T1) increases in serum levels of hepatocyte growth factor and erythropoietin, as well as in cellular PB-EPCs-expression of Hypoxia Inducible Factor-1alpha were observed. CONCLUSION: In conclusion, the endothelial compartment seems quite responsive to standardized brief hypoxia, possibly important for PB-EPCs activation and recruitment.

Effects of surgery on peripheral N-terminal propeptide of type III procollagen in patients with Crohn's disease.

AIM: This study investigates the effects of surgery on collagen turnover in patients affected by Crohn's disease (CD). METHODS: Fifteen patients affected by active CD, assessed according to the Crohn's disease activity index, and confirmed by histology, with different pharmacological treatments, were enrolled in the study. N-Terminal propeptide of type III collagen was assessed on peripheral blood before and 6 months after surgery, as an index of collagen turnover. A control group of 15 healthy age- and sex-matched subjects was also studied. RESULTS: In CD patients peripheral N-terminal propeptide of type III collagen serum levels were significantly higher than in controls before surgery (5.0 +/- 1.8 vs 2.7 +/- 0.7 microg/l, respectively; p = 0.0001). Six months after these values were significantly reduced (from 5.0 +/- 1.8 to 3.1 +/- 0.8 microg/l; p = 0.003). Independently on the pretreatment regimen and the duration of the disease, an improvement in the patients' symptoms was observed. CONCLUSIONS: The surgical resection of the affected intestinal segment in CD patients seems to be able to break down the collagen synthesis processes. Peripheral N-terminal propeptide of type III collagen could be seen as an additive marker to clinical and endoscopic observations after surgery.

Endothelial colony forming capacity is related to C-reactive protein levels in healthy subjects.

The majority of clinical studies on endothelial progenitor cells (EPCs) focuses on the role of these cells in cardiovascular diseases and no systematic studies exist regarding their variations in healthy subjects. In order to define the burden of angiogenesis in physiological conditions we assessed the frequency of peripheral blood endothelial colonies (PB-ECs) and their relation with other factors possibly involved in their function such as high-sensitivity C-reactive protein (hs-CRP), endothelial cell-specific mitogen factor (VEGF) and tissue inhibitor of metalloproteinases-1 (TIMP-1) in a highly selected healthy population. A PB sample was obtained from 37/47 healthy subjects (age 40.2+/-15.0yrs; M/F 15/22) without known cardiovascular risk factors. The serum level of hs-CRP, VEGF, TIMP-1, the frequency of PB-ECs by clonogenic assay, and the number of early EPCs and late EPCs by flow cytometry analysis were evaluated. PB-ECs were formed by 40.5% of studied subjects with a mean of 0.40+/-0.82 colonies/10(6) cells. The differences in the frequency of colony formation between genders were not statistically significant. The subjects with PB-ECs were characterized by higher values of hs-CRP, when compared with those not forming colonies, 0.276+/-0.230 vs 0.095+/-0.077 mg/l (p=0.003) respectively, and of VEGF, 328.3+/-162.9 vs 202.68+/-118.53 pg/ml (p=0.02). No significant differences were found in TIMP-1 values. The EPC clonogenic potential seems to be related to hs-CRP and VEGF levels even in healthy population supporting the concept that these mediators are involved in physiological ECs function.

Different effects of antihypertensive therapies based on losartan or atenolol on ultrasound and biochemical markers of myocardial fibrosis: results of a randomized trial.

BACKGROUND: In hypertensive left ventricular hypertrophy (LVH), myocardial texture is altered by a disproportionate increase in fibrosis, but there is insufficient clinical evidence whether antihypertensive therapy or individual agents can induce regression of myocardial fibrosis. METHODS AND RESULTS: We compared the effects of an angiotensin II receptor antagonist with a beta-blocker on myocardial collagen volume (assessed by echoreflectivity and serum collagen markers) in 219 hypertensive patients with echocardiographically documented LVH. Patients were allocated randomly to receive losartan 50 to 100 mg/d (n=111) or atenolol 50 to 100 mg/d (n=99) with or without hydrochlorothiazide 12.5 to 25 mg/d for 36 weeks. Echoreflectivity analysis was conducted on ultrasound tracings of the midapex septum with specifically designed and validated software. A color histogram of reflecting echoes was obtained, and its spread (broadband [BB], previously shown to correlate directly with collagen volume fraction on endomyocardial biopsies) was used as the primary outcome measure. Mean color scale and serum markers of collagen synthesis (PIP, PIIIP) or degradation (CITP) were secondary outcome variables. Echoreflectivity analysis proved feasible in 106 patients (losartan 52, atenolol 54). Losartan reduced BB over 36 weeks (from 114.5 to 104.3 color levels, P<0.02), whereas atenolol treatment was associated with an increase in BB (from 109.0 to 113.6 color levels, P=NS), the difference between treatments being -12.8 color levels (95% CI -23.6 to -2.0, P=0.02). Secondary end points (mean color scale and collagen markers) also changed in the direction of decreased collagen in patients receiving losartan, but differences between groups were not statistically significant. CONCLUSIONS: In hypertensive patients with LVH, losartan decreases myocardial collagen content, whereas atenolol does not. The difference between the 2 treatments is statistically significant.

Carotid wall composition in hypertensive patients after 4-year treatment with lacidipine or atenolol: an echoreflectivity study.

OBJECTIVE: In the European Lacidipine Study on Atherosclerosis (ELSA), against a similar antihypertensive effect, a significantly greater effect of lacidipine was found on carotid intima-media thickness (IMT) progression, indicating a specific anti-atherosclerotic effect of lacidipine. However, not only the extent but also the composition of an atherosclerotic plaque is a determinant of subsequent events. DESIGN AND METHODS: Among the 2334 patients enrolled in ELSA, 420 with 4-year treatment were chosen, videodensitometric analysis of their ultrasound carotid scan was performed and the maximum wall lesion (Tmax) was classified as lipidic, fibrolipidic and fibrotic by means of software previously validated against histology. Of the 420 patients, 244 had scans suitable for videodensitometry. RESULTS: Excellent reproducibility of videodensitometry analysis was found using the Bland-Altman and other methods. At baseline, ELSA hypertensive patients had predominantly fibrolipidic walls (70%), with an echoreflectivity indicating a mean collagen content of 25%. After 4 years of antihypertensive treatment, little change in the frequency distribution of carotid lesions (fibrolipidic 73%) was found, with no significant differences between patients randomized to lacidipine or atenolol. CONCLUSIONS: Our study provides previously unavailable information that carotid wall composition changes to an extremely small extent during 4-year effective blood pressure lowering. With lacidipine, stable composition is associated with a lower IMT progression than with atenolol.

Assessment of carotid plaque composition in hypertensive patients by ultrasonic tissue characterization: a validation study.

OBJECTIVE: Ultrasonic tissue characterization of epi-aortic vessels may be useful to define the composition of atherosclerotic plaques. Videodensitometry provides a histogram representing the frequency distribution of gray levels corresponding to different compositions of the carotid wall. However, lack of standardization limits the clinical application of this technique. In the present study, the echoreflectivity (ER) pattern of atherosclerotic plaques in vivo was compared with their histological pattern after surgical removal, and the reproducibility of measurement was tested. DESIGN AND METHODS: We studied 19 hypertensive patients with a carotid artery stenosis >or= 70%, eligible for carotid thromboendarterectomy (TEA). Before TEA, all patients underwent standard high-resolution B-mode carotid ultrasound. ER parameters (mean gray level, broad band, skewness, and kurtosis) were obtained in a region of interest selected along the whole plaque, between the intima-blood and the media-adventitia interfaces. The plaques removed during TEA were examined by a histologist and classified into three groups on the basis of fibrous tissue (FT) content: lipidic (FT < 20%), fibrolipidic (20 50%). Discriminant function analysis was used to evaluate classification efficacy of different histological groups based on ER parameters. RESULTS: Histologically, five lesions were classified as lipidic, six as fibrolipidic and eight as fibrous. Analysis of variance showed significant between group differences in all ER parameters. The combined use of all ER parameters provided correct classification of plaques in 94.73% of cases (P < 0.0001), improving the classification made using single parameters. Intra-observer and inter-observer variabilities (Bland-Altman method) of mean gray level measurements were small. CONCLUSIONS: Videodensitometry can discriminate between tissue composition of carotid lesions and complement the quantitative assessment of intima-media thickness by additionally providing a well-reproducible semiquantitative evaluation of vascular wall constituents.

Homing of peripherally injected bone marrow cells in rat after experimental myocardial injury.

BACKGROUND AND OBJECTIVES: Significant progress has been achieved during the past 10 years in cell transplantation and recent research has focused on the possibility of improving ventricular function after myocardial infarction. Most studies in the field of cardiac tissue repair are performed by direct intramyocardial injection of cells of different origin. Since this approach requires a surgical intervention, in this study we investigated the feasibility of non-invasive administration of bone marrow mononuclear cells (BMMNCs) by assessing the fate of peripherally injected, purified, labeled cells in cryodamaged hearts. DESIGN AND METHODS: Ten donor and ten recipient inbred isogenic adult (4 weeks old) Fisher rats were used as models to mimic autologous transplantation. Myocardial damage was obtained in recipient rats by placing a frozen metal probe on the anterior left ventricular wall for 15 seconds (freeze-thaw injury technique). BMMNCs were purified and labeled with a red fluorescent cell dye. Seven days after the injury about 15-25x10(6) cells were infused through the femoral vein of recipient rats. Seven days after the infusion, the heart, lungs, liver, kidneys, spleen and thymus were harvested to track transplanted cells. RESULTS: Labeled cells were found only in the injured area of the heart and not in the normal tissue, and a limited number of cells were identified in the spleen of all the animals. Most of the labeled cells in the infarcted area were Thy-1(+) and some were CD34(+). INTERPRETATION AND CONCLUSIONS: Our data suggest that peripherally injected BMMNCs can traffic through the circulation to the site of damage; we hypothesize that tissue injury leads to the priming of a cytokine cascade acting as chemoattractant for the infused cells.

Elevated serum procollagen type III peptide in splanchnic and peripheral circulation of patients with inflammatory bowel disease submitted to surgery.

BACKGROUND: In the hypothesis that the increased collagen metabolism in the intestinal wall of patients affected by inflammatory bowel disease (IBD) is reflected in the systemic circulation, we aimed the study to evaluate serum level of procollagen III peptide (PIIIP) in peripheral and splanchnic circulation by a commercial radioimmunoassay of patients with different histories of disease. METHODS: Twenty-seven patients, 17 with Crohn and 10 with ulcerative colitis submitted to surgery were studied. Blood samples were obtained before surgery from a peripheral vein and during surgery from the mesenteric vein draining the affected intestinal segment. Fifteen healthy age and sex matched subjects were studied to determine normal range for peripheral PIIIP. RESULTS: In IBD patients peripheral PIIIP level was significantly higher if compared with controls (5.0 +/- 1.9 vs 2.7 +/- 0.7 microg/l; p = 0.0001); splanchnic PIIIP level was 5.5 +/- 2.6 microg/l showing a positive gradient between splanchnic and peripheral concentrations of PIIIP. No significant differences between groups nor correlations with patients' age and duration of disease were found. CONCLUSIONS: We provide evidence that the increased local collagen metabolism in active IBD is reflected also in the systemic circulation irrespective of the history of the disease, suggesting that PIIIP should be considered more appropiately as a marker of the activity phases of IBD.

Intravascular Doppler technique for monitoring renal venous blood flow in man.

BACKGROUND: To measure renal blood flow (RBF) from the renal veins in men using the intravascular Doppler technique (IVD). METHODS: In nine hypertensive male patients (age 46-64 years) undergoing diagnostic renal artery angiography and renal vein catheterization to determine plasma renin activity (PRA), a 3F Doppler catheter was positioned in the renal veins using a 7F guide catheter with a "basket" shaped tip. The radiopaque sectors of the catheter, leaning against the vessel wall, serve to measure the internal diameter of renal veins, and therefore to calculate RBF, by multiplying renal vein cross-sectional area by mean blood flow velocity. The resulting RBF from the left and right renal veins were compared with those obtained by the local thermodilution method (TD). RESULTS: We found good agreement (Bland and Altman's method) between the RBF measurements made with IVD (ranging from 46 mL/min to 1,220 mL/min) and with the TD technique (45-1,030 mL/min) (mean bias, 13+/-20 mL/min, 95% CI -54.77 to 28.77 mL/min). In stenotic kidneys a significant correlation was found between the renal vein PRA and RBF calculated with both methods (IVD: r = 0.96, p = 0.002; TD: r = 0.90, p = 0.01). CONCLUSIONS: The IVD technique applied to the venous side of the renal circulation provides a simple and reliable method for separate measurement of RBF in kidneys with and without renal artery stenosis.

Effects of chronic inflammatory bowel diseases on left ventricular structure and function: a study protocol.

BACKGROUND: Experimental evidences suggest an increased collagen deposition in inflammatory bowel diseases (IBD). In particular, large amounts of collagen type I, III and V have been described and correlated to the development of intestinal fibrotic lesions. No information has been available until now about the possible increased collagen deposition far from the main target organ. In the hypothesis that chronic inflammation and increased collagen metabolism are reflected also in the systemic circulation, we aimed this study to evaluate the effects on left ventricular wall structure by assessing splancnic and systemic collagen metabolism (procollagen III assay), deposition (ultrasonic tissue characterization), and cardiac function (echocardiography) in patients with different long standing history of IBD, before and after surgery. METHODS: Thirty patients affected by active IBD, 15 with Crohn and 15 with Ulcerative Colitis, submitted to surgery will be enrolled in the study in a double blind fashion. They will be studied before the surgical operation and 6, 12 months after surgery. A control group of 15 healthy age and gender-matched subjects will also be studied. At each interval blood samples will be collected in order to assess the collagen metabolism; a transthoracic echocardiogram will be recorded for the subsequent determination of cardiac function and collagen deposition. DISCUSSION: From this study protocol we expect additional information about the association between IBD and cardiovascular disorders; in particular to address the question if chronic inflammation, through the altered collagen metabolism, could affect left ventricular structure and function in a manner directly related to the estimated duration of the disease.

Fibrosis, Enzymatic and Non-Enzymatic Cross-Links in Hypertensive Heart Disease.

Myocardial fibrosis is commonly observed in left ventricular (LV) hypertrophied heart during Arterial Hypertension. This pathological change coupled with vascular stiffening with aging and diabetes may reduce the cardiovascular system elasticity contributing to the functional impairment. Both the LV adaptive response to the increasing blood pressure and the oxidative damage contribute to myocardial fibrosis; in particular, reactive oxygen species (ROS) induce the formation of reactive electrophilic carbonyl species by reacting with lipids and sugars which in turn react with proteins forming irreversible adducts (AGEs, ALEs and EAGLEs) and cross-links. The vascular wall matrix then becomes less distensible, as the formation of the adducts induces greater capacity in collagen to resist normal turnover. Therefore, monitoring cardiac fibrosis and markers of collagen synthesis, degradation and non-enzymatic cross-linking and the use of drugs that revert collagen accumulation and/or prevent/repair non-enzymatic cross-linking might represent a novel opportunity to alter the natural history of hypertensive heart disease. Recent evidences have suggested to target the excess of collagen cross-links; initial evidence seems to show that fibrosis is not affected to the same degree by all anti-hypertensive agents. ACEI and ARBs appear particularly effective. Finally, agents acting as cross-link breakers on AGEs or preventing AGEs formation or affecting the TTG activity are emerging.

Episodes of Fall Asleep During Day Time in an Elder Woman with Vascular Dementia: Impact on Cerebral Ischeamic Tolerance and Utility of ECG Holter Monitoring.

Here we report the case of an 86-year-old woman with advanced dementia addressed to our service for routinary ECG Holter Monitoring (EHM) for bradycardia in AV block type I. Several day-time episodes of fall-asleep while sitting had been previously reported by the nurse and generally attributed to the dementia itself, without taking into consideration the hypothesis of an AV block. The EHM reading reported several and often subsequent pauses (561), many of them critical, the longest lasting 15,9 s with no changes in clinical condition of the patient. The results of the EHM were reported to the physicians in charge for the patient and subsequently the woman was referred to the arrhythmology unit for pace-maker device implantation. Generalizing our experience, we suggest that advanced dementia, often associated with episodes of fall-asleep, could mask a conduction disturbance causing critical pauses with syncope; therefore we suggest screening those patients for possible arrhythmic disorders. Finally, we remark that in our patient the pauses weren't associated with a worsening of the patient as seen in the follow-up, and this fact supports the hypothesis that vascular dementia could increase cerebral ischaemic tolerance.

Experimental animal models of myocardial damage in regenerative medicine studies involving adult bone marrow derived stem cells: ethical and methodological implications.

Cardiac performance after myocardial infarction is compromised by ventricular remodeling, which represents a major cause of late infarct-related chronic heart failure and death. In recent years, the scientists' interest has focused on the hypothesis that the administration of bone marrow progenitors, following myocardial infarction, could ameliorate left ventricular remodeling by continuing to differentiate along the haematopoietic lineage. This approach has been developed minding to the consolidated use of transfusions to restore lost or depleted blood components and, therefore, as an enriched dose of various progenitors, generally autologous, injected peripherally or directly in the infarcted area. Since the safety of this therapy was not yet established, for ethical reasons pioneering researchers involved in these studies used animal models as surrogate of the human biologic system. Herein this hypothesis of therapy resulted in an increased use of living animals and in the reappraisal of models of myocardial damage with limited discussion on the theoretical basis of animal models applied to cell-based therapies. Recently, the European Union and its commission for surveillance of laboratory animals advanced a new proposal to restrict the use of living animals. This review will focus on the history of models utilization in biomedicine, with particular attention to animal models, and delineate an operative comparison between the two best known models of myocardial injury, namely coronary ligation and cryodamage, in the perspective of adult stem cell research applied to cardiovascular regenerative medicine.

Effects of antihypertensive treatment on ultrasound measures of myocardial fibrosis in hypertensive patients with left ventricular hypertrophy: results of a randomized trial comparing the angiotensin receptor antagonist, candesartan and the angiotensin-converting enzyme inhibitor, enalapril.

OBJECTIVE: To compare the effects of the angiotensin II receptor antagonist candesartan with the angiotensin-converting enzyme inhibitor enalapril on myocardial fibrosis evaluated by echoreflectivity analysis. METHODS: Hypertensive patients (n = 196) with echocardigraphically documented left ventricular hypertrophy were randomized to candesartan 8-16 mg/day (n = 91) or enalapril 10-20 mg/day (n = 105) with possible addition of hydrochlorothiazide (12.5-25 mg/day) for 48 weeks. Echoreflectivity analysis was performed on ultrasound two-dimensional tracings of the midapex septum with a specifically designed and validated software. Colour histograms were obtained; the primary outcome variable was the treatment-related change in histogram width (broadband), previously shown to correlate with collagen volume on endomyocardial biopsy; changes in mean colour scale were secondary outcome variable. RESULTS: Echoreflectivity analysis was feasible in 84 patients (48 candesartan, 36 enalapril). Broadband decreased significantly in the candesartan (-8.0 colour levels) and in the enalapril group (-12.9 colour levels) with no significant difference between treatments (P = 0.409); no significant changes occurred in mean colour scale. Patients under monotherapy (n = 46) showed similar trends as the larger intention to treat cohort, without significant difference between treatments. CONCLUSION: In hypertensive patients with left ventricular hypertrophy, both candesartan and enalapril induce a moderate but statistically significant reduction in an echoreflectivity index of myocardial fibrosis.