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Preliminary results suggest that high circulating insulin-like growth factor binding protein 2 (IGFBP2) levels are associated with mortality risk in heart failure (HF) patients. As IGFBP2 levels are increased in patients with chronic kidney disease (CKD), which is associated with a higher mortality risk in HF patients, we examined whether IGFBP2 is associated with CKD in HF patients, and whether CKD modifies the prognostic value of this protein in HF patients.HF patients (n=686, mean age 66.6 years, 32.7% women) were enrolled and followed up for a median of 3.5 (min-max range: 0.1-6) years. Patients were classified as having CKD with decreased estimated glomerular filtration rate (eGFR60mL/min/1.73 mIGFBP2 was increased (P.001) in CKD patients with decreased eGFR (n=290, 42.3%) compared with patients with nondecreased eGFR. IGFBP2 was directly associated with NT-proBNP (P.001) and inversely associated with eGFR (P.001), with both associations being independent of confounding factors. IGFBP2 was directly and independently associated with cardiovascular and all-cause death (P.001) in the whole group of patients, but showed a stronger association with cardiovascular death in CKD patients with decreased eGFR (P for interaction.05), improving risk prediction in these patients over clinically relevant risk factors.Serum IGFBP2 is associated with impaired renal function and prognosticates cardiovascular death in patients with HF and CKD with decreased eGFR. Thus, there is an effect modification of CKD on circulating IGFBP2 and on its association with cardiovascular mortality in HF patients.

Resumen Introduccion y objetivos Los niveles circulantes de la proteina de union del factor de crecimiento de tipo insulina 2 (IGFBP2) aumentan en la insuficiencia renal cronica (IRC), y se asocian con un mayor riesgo de mortalidad en la miocardiopatia dilatada. Dado que la IRC se asocia con una mayor mortalidad en la insuficiencia cardiaca (IC), hemos investigado si, en pacientes con IC de distinta etiologia, IGFBP2 se asocia con la IRC, y si la IRC modifica el valor pronostico de esta proteina. Metodos Se estudiaron pacientes con IC (n = 686, edad media 66,6 anos, 32,7% mujeres) durante 3,5 anos (min-max: 0,1-6 anos). Los pacientes se clasificaron como IRC con una tasa de filtrado glomerular estimada disminuida (TFGe Resultados La IGFBP2 serica estaba aumentada (p Conclusiones Los niveles sericos de IGFBP2 se asocian con un empeoramiento de la funcion renal en pacientes con IC y con un mayor riesgo de muerte cardiovascular, principalmente en los pacientes con IC y IRC con una TFGe disminuida.

Introduction Transthyretin cardiac amyloidosis (ATTR) can be reliably diagnosed in the absence of histology if grade 2 or 3 cardiac uptake is demonstrated on 99mTc-DPD scan (DPD) in the absence of a detectable monoclonal component. Diagnosis requires a high degree of clinical suspicion in the presence of often non-specific findings and that it may be one of the reasons to under-diagnose ATTR. The aim of the study is to identify clinical, analytical and ECG variables that best predict a positive DPD result. Methods This is a multicentre retrospective study including all patients undergoing consecutive 99mTc-DPD scintigraphy in a reference area of 750,000 inhabitants between January 2016 and January 2021 for suspected ATTR. AL amyloidosis patients were excluded. Clinical, analytical, ECG and echocardiographic data were analyzed. We identified variables that independently predicted a positive DPD study using a multivariable logistic regression analysis. Receiver Operating Curve (ROC) analysis and the Area under the Curve (AUC) were calculated to assess the discrimination capacity of the model to predict a positive DPD study. Results DPD scans from a total of 181 patients were analyzed. Mean age of the sample: 78 years (42–96), 100% caucasians, 77% male. 54.7% (N=99) had a positive DPD study (defined as grade 2 or 3 Perugini uptake) and 45.3% (N=82) were negative. Independent predictors of a positive study were age, male gender, left ventricular septum thickness, any grade of atrioventricular block, low QRS voltage, Carpal tunnel syndrome, history of hypotension or need to lower antihypertensive drugs and a NT-proBNP value above 1800 pg/ml (See Table 1). The diagnostic accuracy of the model was excellent, with an AUC of 0.92 (IC 95% 0.87–0.96) (see Figure 1). Conclusions There are clinical-analytical factors and ECG and echocardiogram findings accessible in daily clinical practice that are able to predict a positive result on cardiac scintigraphy requested for suspected ATTR. Identifying these factors may improve the non-invasive diagnosis of ATTR. Funding Acknowledgement Type of funding sources: None. Table 1. Multivariable logistic regression analysFigure 1. ROC curve

Introduction Lack of INR controls might affect the adherence to direct oral anticoagulants (DOAC). The vast majority of studies that addresses adherence to anticoagulants are retrospective and based on pharmacy refill data. Our aim was to compare the adherence between vitamin K antagonists (VKA) and DOAC and to analyze the clinical relevance of non-adherence. Materials and methods A prospective two-arm observational cohort study was performed in two Spanish public hospitals. Adherence was assessed by Medication Event Monitoring System. Relationship between adherence and events during follow-up and time in therapeutic range (TTR) in the VKA group were analyzed. Results 257 patients were included (132 DOAC and 125 VKA). Monitoring time was 120 days (101−133). Patients in VKA group showed higher taking adherence (97.9% vs. 95.8%) and less non-adherent patients of >5% and >10% of the doses, without differences in >20% of the doses. Taking adherence was strongly associated with TTR (AUC: 0.89, CI 95%: 0.81–0.97 of TTR for detection of non-adherent patients of >10% of doses). During a follow-up of 1.8 years (1.6–2) non-adherent patients of >5% of doses presented more thromboembolic events (HR 6.1, CI95% 1.3–28.1). Conclusions Although adherence to oral anticoagulant therapy was excellent, it was higher to VKA than to DOAC. Time in therapeutic range was highly sensitive to few missed doses of AVK. Non-adherence of >5% of prescribed doses had high clinical relevance.

Background A combination of circulating biomarkers associated with excessive myocardial collagen type-I cross-linking or CCL+ (i.e., decreased carboxy-terminal telopeptide of collagen type-I to matrix metalloproteinase-1 ratio) and with excessive myocardial collagen type-I deposition or CD+ (i.e., increased carboxy-terminal propeptide of procollagen type-I) has been described in heart failure (HF) patients and associates with poor outcomes. Objectives The purpose of this study was to investigate whether the CCL+CD+ combination of biomarkers associates with atrial fibrillation (AF). Methods Biomarkers were analyzed in serum samples from 242 HF patients (study 1) and 150 patients referred for AF ablation (study 2). Patients were classified into 3 groups (CCL−CD−, CCL+CD− or CCL−CD+, and CCL+CD+) in accordance to biomarker threshold values. Left atrial electroanatomic high-density mapping was performed in 71 patients from study 2. Results In study 1, 53.7% patients had AF at baseline and 19.6% developed AF (median follow-up 5.5 years). Adjusted odds and hazard ratios associated with baseline and new-onset AF, respectively, were both ≥3.3 (p ≤ 0.050) in CCL+CD+ patients compared with CCL−CD− patients, with nonsignificant changes in the other group. In study 2, 29.3% patients had AF recurrence during 1-year post-ablation. The adjusted hazard ratio for AF recurrence was 3.4 (p = 0.008) in CCL+CD+ patients compared with CCL−CD− patients, with nonsignificant changes in the other group. The CCL+CD+ combination added incremental predictive value over relevant covariables. CCL+CD+ patients exhibited lower left atrial voltage than the remaining patients (p = 0.005). Conclusions A combination of circulating biomarkers reflecting excessive myocardial collagen type-I cross-linking and deposition is associated with higher AF prevalence, incidence, and recurrence after ablation.

Myocardial fibrosis is a main contributor to the development of heart failure (HF). CT-1 (cardiotrophin-1) and Gal-3 (galectin-3) are increased in HF and associated with myocardial fibrosis. The aim of this study is to analyze whether CT-1 regulates Gal-3. Proteomic analysis revealed that Gal-3 was upregulated by CT-1 in human cardiac fibroblasts in parallel with other profibrotic and proinflammatory markers. CT-1 upregulation of Gal-3 was mediated by ERK (extracellular signal-regulated kinase) 1/2 and Stat-3 (signal transducer and activator of transcription 3) pathways. Male Wistar rats and B6CBAF1 mice treated with CT-1 (20 µg/kg per day) presented higher cardiac Gal-3 levels and myocardial fibrosis. In CT-1–treated rats, direct correlations were found between cardiac CT-1 and Gal-3 levels, as well as between Gal-3 and perivascular fibrosis. Gal-3 genetic disruption in human cardiac fibroblasts and pharmacological Gal-3 inhibition in mice prevented the profibrotic and proinflammatory effects of CT-1. Dahl salt-sensitive hypertensive rats with diastolic dysfunction showed increased cardiac CT-1 and Gal-3 expression together with cardiac fibrosis and inflammation. CT-1 and Gal-3 directly correlated with myocardial fibrosis. In HF patients, myocardial and plasma CT-1 and Gal-3 were increased and directly correlated. In addition, HF patients with high CT-1 and Gal-3 plasma levels presented an increased risk of cardiovascular death. Our data suggest that CT-1 upregulates Gal-3 which, in turn, mediates the proinflammatory and profibrotic myocardial effects of CT-1. The elevation of both molecules in HF patients identifies a subgroup of patients with a higher risk of cardiovascular mortality. The CT-1/Gal-3 axis emerges as a candidate therapeutic target and a potential prognostic biomarker in HF.

We investigated the anatomical localization, biomechanical properties, and molecular phenotype of myocardial collagen tissue in 40 patients with severe aortic stenosis with preserved ejection fraction and symptoms of heart failure.Two transmural biopsies were taken from the left ventricular free wall. Mysial and nonmysial regions of the collagen network were analyzed. Myocardial collagen volume fraction (CVF) was measured by picrosirius red staining. Young's elastic modulus (YEM) was measured by atomic force microscopy in decellularized slices to assess stiffness. Collagen types I and III were measured as CCompared with controls, patients exhibited increased mysial and nonmysial CVF and nonmysial:mysial CVF ratio (P.05). In patients, nonmysial CVF (r = 0.330; P = .046) and the nonmysial:mysial CVF ratio (r = 0.419; P = .012) were directly correlated with the ratio of maximal early transmitral flow velocity in diastole to early mitral annulus velocity in diastole. Both the CThese findings suggest that, in patients with severe aortic stenosis with preserved ejection fraction and symptoms of heart failure, diastolic dysfunction is associated with increased nonmysial deposition of collagen, predominantly type I, resulting in increased extracellular matrix stiffness. Therefore, the characteristics of collagen tissue may contribute to diastolic dysfunction in these patients.

Resumen Introduccion y objetivos Se ha estudiado la localizacion anatomica, las propiedades biomecanicas y el fenotipo molecular del colageno miocardico tisular en 40 pacientes con estenosis aortica grave, fraccion de eyeccion conservada y sintomas de insuficiencia cardiaca. Metodos Se obtuvieron 2 biopsias transmurales de la pared libre del ventriculo izquierdo. La fraccion del volumen de colageno (FVC) se cuantifico mediante rojo picrosirio y la rigidez, mediante el modulo elastico de Young (YEM) evaluado con microscopia de fuerza atomica en regiones misiales y no misiales. Las FVC de tipos I y III se cuantificaron mediante microscopia confocal en areas con determinacion del YEM. Resultados Comparados con sujetos de control, la FVC misial y no misial y el cociente FVC no misial:misial (p I :FVC III y el YEM aumentaban (p ≤ 0,001) en regiones no misiales respecto de las misiales, con correlacion entre ellos (r = 0,895; p Conclusiones En la estenosis aortica grave con fraccion de eyeccion conservada y sintomas de insuficiencia cardiaca, la disfuncion diastolica se asocia con un deposito no misial de colageno aumentado, predominantemente de tipo I y con mayor rigidez. Las caracteristicas del colageno tisular pueden contribuir a la disfuncion diastolica en estos pacientes.

Objective Myocardial fibrosis is associated with alterations in the cross-linking and deposition of collagen type I (CCL and CD, respectively). We aimed to evaluate whether the combination of circulating biomarkers of CCL [the carboxy-terminal telopeptide of collagen type I to matrix metalloproteinase-1 ratio (CITP : MMP-1)] and CD [the carboxy-terminal propeptide of procollagen type I (PICP)] identifies myocardial fibrosis phenotypes with distinct clinical outcome in hypertensive patients with heart failure. Methods Endomyocardial biopsies and blood samples from 38 patients (small cohort), and blood samples from 203 patients (large cohort) were analyzed. Myocardial CCL and CD were assessed by histological methods. Serum PICP, CITP, and MMP-1 were determined by ELISA. Results Small cohort: CITP : MMP-1 cutoff 1.968 or less and PICP cutoff at least 110.8 ng/ml were used for predicting high CCL and severe CD, respectively. Large cohort: as defined by the above thresholds, patients were categorized into four subgroups based on the presence (+) or absence (-) of high CCL and severe CD. Compared with CCL-CD-, the adjusted hazard ratios for a composite end point of heart failure hospitalization or cardiovascular death over 5 years in CCL-CD+, CCL+CD-, and CCL+CD+ were 1.11 (P = 0.79), 1.99 (P = 0.07), and 2.18 (P = 0.04), respectively (P for trend = 0.005). In addition, the categorization based on CCL and CD yielded integrated discrimination (P = 0.03) and net reclassification (P = 0.01) improvements for the mentioned outcome. Conclusion The combination of low serum CITP : MMP-1 ratio and high serum PICP identifies hypertensive patients with heart failure presenting with a phenotype of myocardial fibrosis characterized by the concurrence of excessive CCL and CD and associated with poor outcome.

Myocardial fibrosis is a main contributor to the development of heart failure (HF). CT-1 (cardiotrophin-1) and Gal-3 (galectin-3) are increased in HF and associated with myocardial fibrosis. The aim of this study is to analyze whether CT-1 regulates Gal-3. Proteomic analysis revealed that Gal-3 was upregulated by CT-1 in human cardiac fibroblasts in parallel with other profibrotic and proinflammatory markers. CT-1 upregulation of Gal-3 was mediated by ERK (extracellular signal-regulated kinase) 1/2 and Stat-3 (signal transducer and activator of transcription 3) pathways. Male Wistar rats and B6CBAF1 mice treated with CT-1 (20 µg/kg per day) presented higher cardiac Gal-3 levels and myocardial fibrosis. In CT-1-treated rats, direct correlations were found between cardiac CT-1 and Gal-3 levels, as well as between Gal-3 and perivascular fibrosis. Gal-3 genetic disruption in human cardiac fibroblasts and pharmacological Gal-3 inhibition in mice prevented the profibrotic and proinflammatory effects of CT-1. Dahl salt-sensitive hypertensive rats with diastolic dysfunction showed increased cardiac CT-1 and Gal-3 expression together with cardiac fibrosis and inflammation. CT-1 and Gal-3 directly correlated with myocardial fibrosis. In HF patients, myocardial and plasma CT-1 and Gal-3 were increased and directly correlated. In addition, HF patients with high CT-1 and Gal-3 plasma levels presented an increased risk of cardiovascular death. Our data suggest that CT-1 upregulates Gal-3 which, in turn, mediates the proinflammatory and profibrotic myocardial effects of CT-1. The elevation of both molecules in HF patients identifies a subgroup of patients with a higher risk of cardiovascular mortality. The CT-1/Gal-3 axis emerges as a candidate therapeutic target and a potential prognostic biomarker in HF.

OBJECTIVES Cystatin C has been shown to be associated with heart failure with preserved ejection fraction (HFPEF). In addition, myocardial fibrosis has been involved in diastolic dysfunction in HFPEF. Therefore, we hypothesized that increased cystatin C levels may be associated with altered collagen metabolism, contributing to diastolic dysfunction in patients with HFPEF. METHODS One hundred and forty-one elderly hypertensive patients with HFPEF were included. Cardiac morphology and function was assessed by echocardiography. Circulating levels of cystatin C, biomarkers of collagen type I synthesis (carboxy-terminal propeptide of procollagen type I) and degradation [matrix metalloproteinase-1 (MMP-1) and its inhibitor TIMP-1] and osteopontin were analyzed by ELISA. Twenty elderly sex-matched patients with no identifiable cardiac disease were used as controls. In-vitro studies were performed in human cardiac fibroblasts. RESULTS Compared with controls, cystatin C was increased (P

BackgroundExcessive myocardial collagen cross-linking (CCL) determines myocardial collagen’s resistance to degradation by matrix metalloproteinase (MMP)-1 and interstitial accumulation of collagen fibers with impairment of cardiac function.ObjectivesThis study sought to investigate whether CCL and a newly identified biomarker of this alteration are associated with hospitalization for heart failure (HHF) or cardiovascular death in patients with HF and arterial hypertension in whom other comorbidities were excluded.MethodsEndomyocardial biopsies and blood samples from 38 patients (invasive study), and blood samples from 203 patients (noninvasive study) were analyzed. Mean follow-ups were 7.74 ± 0.58 years and 4.72 ± 0.11 years, respectively. Myocardial CCL was calculated as the ratio between insoluble and soluble collagen. The ratio between the C-terminal telopeptide of collagen type I (CITP) and matrix metalloproteinase-1 (CITP:MMP-1) was determined in blood samples.ResultsInvasive study: CCL was increased (p < 0.001) in patients compared with controls. Patients were categorized according to normal or high CCL values. Patients with high CCL exhibited higher risk for subsequent HHF (log-rank test p = 0.022), but not for cardiovascular death. CITP:MMP-1 was inversely associated with CCL (r = −0.460; p = 0.005) in all patients. Receiver operating characteristic curves rendered a CITP:MMP-1 cutoff ≤1.968 (80% sensitivity and 76% specificity) for predicting high CCL. Noninvasive study: Patients were categorized according to CITP:MMP-1 ratio values as normal ratio (>1.968) or low ratio (≤1.968). Patients with a low ratio exhibited higher risk for HHF (log-rank test p = 0.014), which remained significant after adjustment for relevant covariables (adjusted hazard ratio: 2.22; 95% CI: 1.37 to 3.59, p = 0.001). In addition, CITP:MMP-1–based categorization yielded significant integrated discrimination and net reclassification improvements (p = 0.003 and p = 0.009, respectively) for HHF over relevant risk factors. CITP:MMP-1 was not associated with the risk of cardiovascular death.ConclusionsExcessive myocardial CCL is associated with HHF in hypertensive patients with HF. In this population, the serum CITP:MMP-1 ratio identifies patients with increased CCL and high risk of HHF.

Hypertensive heart disease (HHD) is the cardiomyopathy resulting from the response of the myocardium to the biomechanical stress imposed on the left ventricle by progressively increasing blood pressure. HHD is characterized by the presence of left ventricular hypertrophy (LVH). Complex alterations in myocardial histological composition (myocardial remodeling) underlie LVH and explain the overall risk of LVH and its associated cardiac complications. LVH may be accurately detected in hypertensive patients. Effective, long-term antihypertensive treatment is associated with regression of LVH. However, adequately treated patients still have considerable residual cardiovascular risk. Novel diagnostic and therapeutic approaches are needed to reduce adverse outcomes in HHD.

Myocardial fibrosis impairs cardiac function, in addition to facilitating arrhythmias and ischemia, and thus influences the evolution and outcome of cardiac diseases. Its assessment is therefore clinically relevant. Although tissue biopsy is the gold standard for the diagnosis of myocardial fibrosis, a number of circulating biomarkers have been proposed for the noninvasive assessment of this lesion. A review of the published clinical data available on these biomarkers shows that most of them lack proof that they actually reflect the myocardial accumulation of fibrous tissue. In this “call to action” article, we propose that this absence of proof may lead to misinterpretations when considering the incremental value provided by the biomarkers with respect to traditional diagnostic tools in the clinical handling of patients. We thus argue that strategies are needed to more strictly validate whether a given circulating biomarker actually reflects histologically proven myocardial fibrosis before it is applied clinically.

Aims The aim of this study was to investigate whether galectin-3 (Gal-3) is associated with myocardial histological and molecular parameters related to fibrosis and with the circulating biomarkers of the extracellular generation of mature fibril-forming collagen types I (C-terminal propeptide of procollagen type I, PICP) and III (N-terminal propeptide of procollagen type III, PIIINP) in two independent studies of hypertensive patients with heart failure (HF). Methods and results Endomyocardial biopsies and blood samples from 39 HF patients (invasive study), and blood samples from 220 HF patients (non-invasive study) were analysed. Necropsies (n = 7) and blood samples (n = 20) from healthy subjects were used as controls. In the invasive study myocardial mRNA and protein expression of Gal-3 and collagen types I and III, plasma Gal-3 and serum PICP and PIIINP were all significantly increased in patients compared with controls. Neither myocardial nor plasma Gal-3 were correlated with myocardial collagen and circulating biomarkers; whereas PICP was correlated with myocardial total (r = 0.819, P

Aims We investigated whether the pro-fibrotic matricellular protein osteopontin (OPN) is associated with the enzymes involved in the extracellular synthesis of fibril-forming collagen type I (i.e. procollagen C-proteinase, PCP) and its cross-linking to form insoluble fibrils (i.e. lysyl oxidase, LOX) in heart failure (HF) of hypertensive origin. Methods and results OPN, PCP, and LOX were assessed by histochemical and molecular methods in the myocardium of 21 patients with hypertensive heart disease (HHD) and HF. Whereas the myocardial expression of OPN was very scarce in control hearts ( n = 10), it was highly expressed in HF patients ( P < 0.0001). OPN was directly correlated with LOX ( r = 0.460, P = 0.041), insoluble collagen ( r = 0.534, P = 0.015), pulmonary capillary wedge pressure ( r = 0.558; P = 0.009), and left-ventricular (LV) chamber stiffness ( r = 0.458, P = 0.037), and inversely correlated with LV ejection fraction ( r = −0.513, P = 0.017) in all patients. OPN did not correlate with PCP and other parameters assessing collagen synthesis by fibroblasts or degradation by matrix metalloproteinases. In vitro studies showed that OPN significantly ( P < 0.05) increases the expression and activity of LOX in human cardiac and dermal fibroblasts. Conclusion An excess of OPN is associated with increased LOX and insoluble collagen, as well as with LV stiffness and systolic dysfunction in patients with HHD and HF. In addition, OPN up-regulates LOX in human fibroblasts. It is suggested that the OPN–LOX axis might facilitate the formation of insoluble collagen (i.e. stiff and resistant to degradation) and the subsequent alteration in LV mechanical properties and function in patients with HHD and HF.

We investigated whether the quality of myocardial collagen associates with elevated left-sided filling pressures in 38 hypertensive patients with stage C chronic heart failure. Filling pressures were assessed invasively measuring pulmonary capillary wedge pressure. Left ventricular chamber stiffness constant was calculated from the deceleration time of the early mitral filling wave. The fraction of myocardial volume occupied by total collagen tissue and collagen type I fibers was assessed histomorphologically. The degree of collagen cross-linking (CCL), which determines the formation of insoluble stiff collagen, was assessed by colorimetric and enzymatic procedures. The expression of lysyl oxidase (LOX), which regulates CCL, was assessed by Western blot. Compared with patients with normal pulmonary capillary wedge pressure (≤12 mm Hg; n=16), patients with elevated pulmonary capillary wedge pressure (>12 mm Hg; n=22) exhibited increases of left ventricular chamber stiffness constant, fraction of myocardial volume occupied by total collagen tissue, fraction of myocardial volume occupied by collagen type I fibers, CCL, insoluble stiff collagen, and LOX. Pulmonary capillary wedge pressure was correlated with left ventricular chamber stiffness constant ( r =0.639; P r =0.474; P r =0.625; P r =0.410; P r =0.612; P r =0.538; P r =0.535; P r =−0.343; P r =−0.430; P r =0.421; P

Cardiotrophin-1 is a cytokine that induces hypertrophy and dysfunction in cardiomyocytes and has been shown to be increased in hypertensive patients. The objective of this study was to evaluate the association of cardiotrophin-1 with heart failure (HF) in hypertensive patients and its usefulness as a biomarker of stage C heart failure. Hypertensive patients without cardiac abnormalities (stage A, n = 64), with left ventricular hypertrophy (LVH) (stage B, n = 58), and with left ventricular hypertrophy and clinical manifestations of chronic heart failure (stage C, n = 39) were studied. Plasma cardiotrophin-1 was measured by an enzyme-linked inmunosorbent assay. Plasma cardiotrophin-1 progressively increased (P < 0.001), along with progression of heart failure stages, in hypertensive patients. Plasma cardiotrophin-1 was directly (r = 0.416, P < 0.001) and inversely (r = 0.263, P < 0.01) correlated with left ventricular (LV) mass index and ejection fraction, respectively, in all hypertensive patients. These associations were independent of a number of potential confounding factors. Receiver operating characteristic curves showed that a cut-off of 48.72 fmol/ml for cardiotrophin-1 provided higher sensitivity for diagnosing stage C heart failure than a cut-off of 375.54 pg/ml for amino-terminal probrain natriuretic peptide (NT-proBNP) (80% vs. 72%). Sixty-four percent of stage C hypertensive patients with NT-proBNP values below 375.54 pg/ml value exhibited cardiotrophin-1 values above 49.16 fmol/ml. These findings indicate that plasma cardiotrophin-1 is associated with progression of heart failure in hypertensive patients. Cardiotrophin-1 measurement may provide additional information to that afforded by NT-proBNP to diagnose stage C heart failure in these patients.

The aim of this study was to investigate whether torasemide modifies collagen cross-linking in the failing human heart. We analyzed the degree of cross-linking and the expression of the enzyme lysyl oxidase, which regulates cross-linking, in the myocardium of patients with chronic heart failure at baseline and after 8 months of treatment with either torasemide or furosemide in addition to their standard heart failure therapy. Whereas lysyl oxidase protein expression was very scarce in normal hearts, it was highly expressed in failing hearts. Cross-linking was increased ( P P =0.021 and P =0.034) in torasemide-treated patients and remained unchanged in furosemide-treated patients. In addition, more ( P =0.009) patients showed normalization of left ventricular chamber stiffness in the torasemide subgroup than in the furosemide subgroup after treatment. Lysyl oxidase expression correlated with cross-linking ( r =0.661; P r =0.452; P =0.002) in all patients. These findings show for the first time that lysyl oxidase overexpression is associated with enhanced collagen cross-linking in the failing human heart. In addition, we report that the ability of torasemide to correct both lysyl oxidase overexpression and enhanced collagen cross-linking results in normalization of left ventricular chamber stiffness in patients with heart failure. Lysyl oxidase may thus represent a target for reduction of stiff collagen and improvement of left ventricular mechanical properties in heart failure patients.

It is time to recognize that the quality, not quantity, of myocardium in hypertensive heart disease is responsible for adverse cardiovascular events. Experimental and clinical available data indicate that myocardial fibrosis due to the exaggerated accumulation of collagen type I and type III fibers predisposes to an enhanced risk of diastolic and/or systolic ventricular dysfunction, symptomatic heart failure, ischemic heart disease, and arrhythmias in patients with hypertensive heart disease. Thus, management of these patients must not only focus on detection and regression of left ventricular hypertrophy. Far more sensible are interventions aimed to detect and target hypertensive myocardial fibrosis. The available data on the use of biochemical and/or imaging methodologies to address excessive accumulation of collagen fibers in the myocardium of hypertensive patients are promising. On the other hand, preliminary data suggest that the goal of reducing myocardial fibrosis is achievable in patients with hypertensive heart disease treated with specific antihypertensive agents. Collectively, these findings set the stage for larger trials where-in noninvasive measures and reparative strategies of myocardial fibrosis to prevent heart failure could prove useful.

Desde el punto de vista molecular, la cardiopatia hipertensiva se caracteriza por un conjunto de cambios en la expresion de genes y proteinas del miocardio que provocan una serie de modificaciones en su composicion, dando lugar a su remodelado estructural y geometrico, asi como a alteraciones de su funcion, perfusion y actividad electrica. El remodelado es la consecuencia tanto de la sobrecarga mecanica hipertensiva como de la activacion local de diversos factores humorales que afectan a los cardiomiocitos (facilitando su muerte por apoptosis) y a la matriz extracelular miocardica (dando lugar a cambios en la cuantia y el deposito de las fibras de colageno). La relevancia clinica de estas lesiones radica en que contribuyen a la transicion de la hipertrofia ventricular izquierda a la insuficiencia cardiaca en los pacientes con cardiopatia hipertensiva. Hallazgos recientes senalan nuevos mecanismos de apoptosis y fibrosis (p. ej., alteraciones del receptor alfa activado por proliferadores de peroxisomas) en el ventriculo hipertenso que abren vias nuevas para la prevencion de la insuficiencia cardiaca en los pacientes con cardiopatia hipertensiva.

Arterial hypertension induces numerous alterations in the composition of cardiac tissue, which, in turn, result in structural remodeling of the myocardium. This remodeling is due to a range of pathologic mechanisms associated with mechanical, neurohormonal and cytokine processes that affect both cardiomyocyte and non-cardiomyocyte compartments of the myocardium. One of these processes involves disruption of the equilibrium between the synthesis and degradation of type-I and type-III collagen molecules. The result is excess accumulation of type-I and type-III collagen fibers in interstitial and perivascular spaces in the myocardium. The clinical significance of myocardial fibrosis lies in its contribution to the development of cardiac complications in hypertensive patients. This brief review focuses on the mechanisms of myocardial fibrosis and their clinical consequences. In addition, the techniques used for diagnosing myocardial fibrosis and the main therapeutic strategies for reducing fibrosis are also discussed.

Given the importance of fibrous tissue in leading to myocardial dysfunction and failure in hypertensive heart disease, non-invasive assessment of fibrosis could prove a clinically useful tool in hypertensive patients, particularly given the potential for cardioprotective and cardioreparative pharmacological strategies. In this regard, an emerging experimental and clinical experience holds promise for the assessment of various serum peptides arising from the metabolism of collagen types I and III in arterial hypertension. More specifically, the measurement of serum concentrations of procollagen type I carboxy-terminal propeptide (a peptide that is cleaved from procollagen type I during the synthesis of fibril-forming collagen type I) may provide indirect diagnostic information on both the extent of myocardial fibrosis and the ability of antihypertensive treatment to diminish collagen type I synthesis and reduce myocardial fibrosis in hypertensive patients. The available data set the stage for large and long-term trials to definitively validate this approach.

Changes in the composition of cardiac tissue develop in arterial hypertension and lead to structural remodeling of the myocardium. Structural remodeling is the consequence of a number of pathologic processes, mediated by mechanical, neurohormonal and cytokine routes, occurring in the cardiomyocyte and the noncardiomyocyte compartments of the heart. One of these processes is related to the disruption of the equilibrium between the synthesis and degradation of collagen type I and III molecules, which results in an excessive accumulation of collagen type I and III fibers in the interstitium and the perivascular regions of the myocardium. The clinical relevance of ventricular fibrosis is that it might contribute to the increased cardiac risk of patients with hypertensive heart disease. This review focuses on the mechanisms of hypertensive ventricular fibrosis and its clinical consequences. In addition, we discuss the noninvasive methods for the diagnosis of cardiac fibrosis and the therapeutic strategies aimed to promote its reduction.

Background— We investigated whether increased collagen type I synthesis and deposition contribute to enhancement of myocardial fibrosis and deterioration of cardiac function in patients with hypertensive heart disease (HHD). Methods and Results— We studied 65 hypertensives with left ventricular hypertrophy subdivided into 2 groups: 34 patients without heart failure (HF) and 31 patients with HF. Transvenous endomyocardial biopsies of the interventricular septum were performed to quantify the amount of fibrotic tissue and the extent of collagen type I deposition. The carboxy-terminal propeptide of procollagen type I (PIP), an index of collagen type I synthesis, was measured by radioimmunoassay in serum samples from the coronary sinus and the antecubital vein. Compared with normotensives, the amount of collagen tissue, the extent of collagen type I deposition, and coronary and peripheral PIP were increased ( P P P Conclusions— These findings suggest that an excess of cardiac collagen type I synthesis and deposition may be involved in the enhancement of myocardial fibrosis that accompanies the development of HF in HHD. In addition, our data show that the heart secretes PIP via the coronary sinus into the peripheral circulation in patients with HHD. Thus, PIP determined in peripheral blood can be a useful marker of myocardial fibrosis in these patients.

Background — This study was designed to investigate whether myocardial collagen content is related to myocardial stiffness in patients with essential hypertension. Methods and Results — The study was performed in 34 patients with hypertensive heart disease. Nineteen of these patients were also evaluated after 12 months of treatment with losartan. Transvenous endomyocardial biopsies of the interventricular septum were performed to quantify collagen volume fraction (CVF). Left ventricular (LV) chamber stiffness (K LV ) was determined from the deceleration time of the early mitral filling wave as measured by Doppler echocardiography. Histological analysis at baseline revealed the presence of 2 subgroups of patients: 8 with severe fibrosis and 26 with nonsevere fibrosis. Values of CVF and K LV were significantly higher in the 2 subgroups of hypertensives than in normotensives. In addition, compared with patients with nonsevere fibrosis, patients with severe fibrosis exhibited significantly increased values of CVF and K LV . After treatment, CVF and K LV decreased significantly in patients with severe fibrosis (n=7). None of these parameters changed significantly after treatment in patients with nonsevere fibrosis (n=12). CVF was directly correlated with K LV ( r =0.415, P Conclusions — These findings show a strong association between myocardial collagen content and LV chamber stiffness in patients with essential hypertension. Our results also suggest that the ability of losartan to induce regression of severe myocardial fibrosis is associated with diminution of myocardial stiffness in hypertensive patients.

The aim of this study was to investigate whether galectin-3 (Gal-3) is associated with myocardial histological and molecular parameters related to fibrosis and with the circulating biomarkers of the extracellular generation of mature fibril-forming collagen types I (C-terminal propeptide of procollagen type I, PICP) and III (N-terminal propeptide of procollagen type III, PIIINP) in two independent studies of hypertensive patients with heart failure (HF).Endomyocardial biopsies and blood samples from 39 HF patients (invasive study), and blood samples from 220 HF patients (non-invasive study) were analysed. Necropsies (n = 7) and blood samples (n = 20) from healthy subjects were used as controls. In the invasive study myocardial mRNA and protein expression of Gal-3 and collagen types I and III, plasma Gal-3 and serum PICP and PIIINP were all significantly increased in patients compared with controls. Neither myocardial nor plasma Gal-3 were correlated with myocardial collagen and circulating biomarkers; whereas PICP was correlated with myocardial total (r = 0.819, P 0.001) and collagen type I (r = 0.744, P 0.001) deposition, PIIINP was not. In the non-invasive study both plasma Gal-3 and serum PICP were increased (P 0.001) in patients compared with controls. No correlation was found between Gal-3 and PICP in HF patients.These findings show that although an excess of cardiac and systemic Gal-3 is present in patients with HF of hypertensive origin, this molecule is not associated with histological, molecular and biochemical parameters related to myocardial fibrosis in these patients.

Myocardial fibrosis is one of the histologic constituents of myocardial remodeling present in hypertensive patients with hypertensive heart disease. In fact, an exaggerated interstitial and perivascular accumulation of fibrillar collagens type I and type III has been found in the myocardium of patients with arterial hypertension and left ventricular hypertrophy. Hypertensive myocardial fibrosis has been shown to facilitate abnormalities of cardiac function, coronary reserve, and electrical activity that adversely affect the clinical outcome of hypertensive patients. Therefore, development of noninvasive tools for the monitoring of myocardial fibrosis and pharmacological strategies aimed to promote the regression of fibrosis could be of particular relevance in the clinical treatment of patients with hypertensive heart disease.

Fibrous tissue accumulation is an integral feature of the adverse structural remodeling of cardiac tissue seen with hypertensive heart disease. Given the importance of fibrous tissue in leading to myocardial dysfunction and failure, noninvasive monitoring of myocardial fibrosis by use of serological markers of collagen turnover could prove a clinically useful tool, particularly given the potential for cardioprotective and cardioreparative pharmacological strategies. An emerging experimental and clinical experience holds promise for the use of radioimmunoassays of various serological markers of fibrillar collagen type I and type III turnover in arterial hypertension. More specifically, the measurement of serum concentrations of procollagen type I C-terminal propeptide (a peptide that is cleaved from procollagen type I during the synthesis of fibril-forming collagen type I) may provide indirect diagnostic information on both the extent of myocardial fibrosis and the ability of antihypertensive treatment to diminish collagen type I synthesis and reduce myocardial fibrosis. This approach represents an exciting and innovative strategy, and available data set the stage for larger trials, in which noninvasive measures of fibrosis in hypertensive heart disease could prove useful.

Background We investigated whether serum concentration of carboxy-terminal propeptide of procollagen type I (PIP), a marker of collagen type I synthesis, can be used to assess the ability of antihypertensive treatment to regress myocardial fibrosis in hypertensive patients. Methods and Results The study was performed in 37 patients with essential hypertension and hypertensive heart disease. After randomization, 21 patients were assigned to losartan and 16 patients to amlodipine treatment. At baseline and after 12 months, right septal endomyocardial biopsies were performed to quantify collagen volume fraction (CVF) on picrosirius red–stained sections with an automated image-analysis system. Serum PIP was measured by specific radioimmunoassay. Nineteen patients in the losartan group and 11 in the amlodipine group finished the study. Time-course changes in blood pressure during treatment were similar in the 2 groups of patients. In losartan-treated patients, CVF decreased from 5.65±2.03% to 3.96±1.46% ( P P r =0.44, P Conclusions These findings suggest that the ability of antihypertensive treatment to regress fibrosis in hypertensives with biopsy-proven myocardial fibrosis is independent of its antihypertensive efficacy. Our data also suggest that blockade of the angiotensin II type 1 receptor is associated with inhibition of collagen type I synthesis and regression of myocardial fibrosis in hypertensives. Thus, determination of serum PIP may be useful to assess the cardioreparative properties of antihypertensive treatment in hypertensives.

Cardiotrophin-1 has been shown to be profibrogenic in experimental models. The aim of this study was to analyze whether cardiotrophin-1 is associated with left ventricular end-diastolic stress and myocardial fibrosis in hypertensive patients with heart failure. Endomyocardial biopsies from patients (n=31) and necropsies from 7 control subjects were studied. Myocardial cardiotrophin-1 protein and mRNA and the fraction of myocardial volume occupied by collagen were increased in patients compared with controls ( P r =0.653, P r =0.541, P r =0.588, P r =0.556, P r =0.450; P P r =0.386; P r =0.550; P r =0.267; P P P P

This study was designed to evaluate the association between circulating biomarkers of collagen metabolism and elevated left-sided filling pressures (FPs), as assessed from elevated estimated pulmonary capillary wedge pressure (ePCWP), in hypertensive patients with heart failure with normal ejection fraction. Echocardiography was performed and ePCWP was calculated from the formula ePCWP=1.90+1.24(maximum early transmitral flow velocity in diastole:tissue Doppler early mitral annulus velocity). The biomarkers of collagen synthesis (carboxy-terminal propeptide of procollagen type I) and degradation (matrix metalloproteinase [MMP] 1 and tissue inhibitor of MMP-1 [TIMP-1]) were analyzed by ELISA methods. Seventy-eight patients with normal FPs (ePCWP ≤15 mm Hg) and 78 with elevated FPs (ePCWP >15 mm Hg) were included. Compared with controls, the levels of the 3 biomarkers were increased in the 2 groups of patients. The MMP-1:TIMP-1 ratio, an index of MMP-1 activity, was increased in patients with normal FPs and unchanged in patients with elevated FPs. Patients with elevated FPs exhibited higher TIMP-1 levels and a lower MMP-1:TIMP-1 ratio than patients with normal FPs. ePCWP was independently associated with TIMP-1 ( r =0.349; P r =−0.240; P

Phospholipase C-beta (PLCbeta) isozymes (PLCbeta(1) and PLCbeta(3)) have been extensively characterized in cardiac tissue, but no data are available for the PLCbeta(4) isozyme. In this study, PLCbeta((1-4)) isozymes mRNA relative expression was studied by real-time PCR (RT-PCR) in human, rat, and murine left ventricle and the presence of PLCbeta(4) isozyme at the protein level was confirmed by Western blotting in all species studied. Confocal microscopy experiments carried out in HL-1 cardiomyocytes revealed a sarcoplasmic subcellular distribution of PLCbeta(4). Although there were unexpected significant interspecies differences in the PLCbeta((1-4)) mRNA expression, PLCbeta(4) mRNA was the main transcript expressed in all left ventricles studied. Thus, whereas in human and rat left ventricles PLCbeta(4)PLCbeta(3)PLCbeta(2)PLCbeta(1) mRNA pattern of expression was found, in murine left ventricle the pattern of expression was different, i.e., PLCbeta(4)PLCbeta(1)PLCbeta(3)PLCbeta(2). However, results obtained in mouse HL-1 cardiomyocytes showed PLCbeta(3) approximately PLCbeta(4)PLCbeta(1)PLCbeta(2) pattern of mRNA expression indicating a probable cell type specific expression of the different PLCbeta isozymes in cardiomyocytes. Finally, RT-PCR experiments showed a trend, even though not significant (P = 0.067), to increase PLCbeta(4) mRNA levels in HL-1 cardiomyocytes after angiotensin II treatment. These results demonstrate the presence of PLCbeta(4) in the heart and in HL-1 cardiomyocytes showing a different species-dependent pattern of expression of the PLCbeta((1-4)) transcripts. We discuss the relevance of these findings in relation to the development of cardiac hypertrophy.

AIMS: To investigate whether Annexin A5 (AnxA5) is related to hypertensive heart disease (HHD) and whether this relation is dependent of apoptosis. METHODS AND RESULTS: Hypertensives without cardiac abnormalities (stage A), with left ventricular hypertrophy (LVH) (stage B), and with LVH and clinical manifestations of chronic HF (stage C), were studied. AnxA5 was quantified in endomyocardial biopsies by real time RT-PCR, Western blot, and immunohistochemistry, and apoptosis by DNA fragmentation, caspase-3 activation, and PARP and Bax/Bcl-2 ratios. Plasma AnxA5 was measured by ELISA in samples from the coronary sinus and the antecubital vein. Although AnxA5 mRNA did not change, myocardial and plasma AnxA5 were increased in hypertensives stages B and C compared with normotensives and hypertensives stage A. Myocardial AnxA5 was inversely correlated with parameters assessing systolic function in all hypertensives, this association being independent of apoptosis. Myocardial AnxA5 was directly correlated with plasma AnxA5. Plasma AnxA5 was inversely correlated with systolic function in all hypertensives. CONCLUSION: This cross-sectional study shows that myocardial AnxA5 upregulation is associated with HHD and impairment of systolic function in hypertensive patients, this association being independent of apoptosis. Plasma AnxA5 can be a marker of myocardial AnxA5 upregulation and systolic dysfunction in patients with HHD.

OBJECTIVE: To investigate whether the glycoprotein (gp130)-mediated survival pathway, which protects cardiomyocytes from apoptosis, is depressed in left ventricular hypertrophy hypertensive patients with chronic heart failure. METHODS: Transvenous endomyocardial biopsies were obtained in 52 hypertensive patients with left ventricular hypertrophy: 28 without heart failure and 24 with heart failure. gp130 and gp130-dependent antiapoptotic pathways p42/44 mitogen-activated protein kinase (MAPK) and phosphatidylinositol-3 kinase (PI3K)/protein kinase B (Akt) as well as gp130 agonist cardiotrophin-1 were analyzed by reverse transcriptase-polymerase chain reaction and western blot. Apoptosis was assessed by DNA end-labeling (TUNEL), caspase-3 immunostaining and caspase substrate poly(ADP-ribose) polymerase cleavage. RESULTS: gp130 protein expression (P < 0.05) and p42/44 MAPK and PI3K/Akt activation (P < 0.01) were decreased in heart-failure hypertensive patients compared with nonheart-failure hypertensive individuals. No changes in gp130 mRNA expression were found between the two groups. Cardiotrophin-1 was increased (P < 0.05) at both the mRNA and protein levels in heart-failure hypertensive individuals compared with nonheart-failure hypertensive individuals. Cardiomyocyte apoptosis was increased (P < 0.01) in heart-failure hypertensive individuals compared with nonheart-failure hypertensive individuals. Inverse correlations (P < 0.01) occurred between cardiomyocyte apoptosis and p42/44 MAPK and PI3K/Akt activation in all hypertensive patients. Cardiotrophin-1 correlated inversely (r = -0.554, P < 0.05) with gp130 in all hypertensive individuals. In cultured HL-1 cardiomyocytes, cardiotrophin-1 decreased (P < 0.05) the gp130:phosphorylated gp130 (at Ser782) ratio and increased (P < 0.05) gp130ubiquitination. CONCLUSIONS: An association exists between depression of the gp130 cytoprotective pathway and stimulation of cardiomyocyte apoptosis in hypertensive patients that develop heart failure. Whether the excess of cardiotrophin-1 induces ligand-induced receptor down-regulation in these patients requires further study.

Arterial hypertension induces numerous alterations in the composition of cardiac tissue, which, in turn, result in structural remodeling of the myocardium. This remodeling is due to a range of pathologic mechanisms associated with mechanical, neurohormonal and cytokine processes that affect both cardiomyocyte and non-cardiomyocyte compartments of the myocardium. One of these processes involves disruption of the equilibrium between the synthesis and degradation of type-I and type-III collagen molecules. The result is excess accumulation of type-I and type-III collagen fibers in interstitial and perivascular spaces in the myocardium. The clinical significance of myocardial fibrosis lies in its contribution to the development of cardiac complications in hypertensive patients. This brief review focuses on the mechanisms of myocardial fibrosis and their clinical consequences. In addition, the techniques used for diagnosing myocardial fibrosis and the main therapeutic strategies for reducing fibrosis are also discussed.

PURPOSE OF REVIEW: It is widely accepted that there are two principal forms of cell death, namely, necrosis and apoptosis. According to the classical view, necrosis is the major mechanism of cardiomyocyte death in cardiac diseases. RECENT DEVELOPMENTS: In the past few years observations have been made showing that cardiomyocyte apoptosis occurs in diverse conditions including hypertensive heart disease, and that apoptosis may be a contributing cause of loss and functional abnormalities of cardiomyocytes in this condition. SUMMARY: This review will summarize recent evidence demonstrating the potential contribution of cardiomyocyte apoptosis to heart failure in hypertensive patients. In addition, some strategies aimed to detect and prevent apoptosis of cardiomyocytes will be considered.

ANG II has endocrine, autocrine and paracrine properties that influence the behaviour of cardiac cells and matrix via AT1 receptor binding. Thus, various paradigms have been suggested, including ANG II-triggered apoptosis of cardiomyocytes and ANG II-mediated upregulation of collagen types I and II formation and deposition in HHD. On the other hand, a growing body of evidence deals with the potential role of ALDO, either local or systemic, in inducing cardiac fibrosis and apoptosis. Thus, aldosterone might also mediate the profibrotic and proapoptotic actions of ANG II. To reduce the risk of heart failure that accompanies HHD, its adverse structural remodeling must be targeted for pharmacological intervention. Available experimental and clinical data suggest that agents interfering with either ACE, the AT1 receptor, or the mineralocorticoid receptor may provide such a cardioprotective effect.

OBJECTIVES: We sought to assess the distribution of collagen deposits and collagen degradation in hypertensive patients with either systolic heart failure (SHF) or diastolic heart failure (DHF). BACKGROUND: Increased collagen synthesis and deposition have been described in the myocardium of heart failure (HF) hypertensive patients. METHODS: We studied 39 HF hypertensive patients subdivided into two groups: 16 with SHF and 23 with DHF. Endomyocardial biopsies were performed to quantify mysial (i.e., perimysial plus endomysial) and perivascular and scar-related collagen volume fraction (CVF). Matrix metalloproteinase (MMP)-1 and its tissue inhibitor matrix metalloproteinase (TIMP)-1 were analyzed in cardiac samples by Western blot and immunohistochemistry, and in blood samples by enzyme-linked immunosorbent assay. RESULTS: Mysial CVF was lower in SHF hypertensive patients than in normotensive (p < 0.05) and DHF hypertensive patients (p < 0.01). Perivascular and scar-related CVF was higher (p < 0.05) in the two groups of hypertensive patients than in normotensive subjects, and in SHF hypertensive compared with DHF hypertensive patients. The MMP-1:TIMP-1 ratio was increased (p < 0.05) in tissue and serum samples from the SHF hypertensive group compared with the other two groups of subjects. The MMP-1 expression was increased (p < 0.01) in the interstitium and cardiomyocytes of SHF hypertensive patients compared with DHF hypertensive and normotensive subjects. The serum MMP-1:TIMP-1 ratio was inversely correlated with ejection fraction (r = -0.510, p < 0.001) and directly correlated with left ventricular end-diastolic diameter (r = 0.549, p < 0.001) in all subjects. CONCLUSIONS: These findings show that the pattern of collagen deposits and the balance of the MMP-1/TIMP-1 system are different in the myocardium of SHF and DHF hypertensive patients. It is proposed that excessive degradation of mysial collagen may be related to the compromise of systolic function in HF hypertensive patients.

It is widely accepted that there are two principal forms of cell death; namely, necrosis and apoptosis. According to the classical view, necrosis is the major mechanism of cardiomyocyte death in cardiac diseases. However, in the past few years observations have been made showing that cardiomyocyte apoptosis occurs in diverse conditions and that apoptosis may be a contributing cause of the loss and functional abnormalities of cardiomyocytes with important pathophysiological consequences. In this regard, although a number of formal proofs are pending, it is conceivable that cardiomyocyte apoptosis may be an important variable in the clinical evolution of hypertensive cardiomyopathy. This review summarizes recent evidence demonstrating that cardiomyocyte apoptosis is abnormally stimulated in the heart of animals and humans with arterial hypertension. In addition, the potential mechanisms of cardiomyocyte apoptosis in hypertension and its detrimental impact on cardiac function will be addressed. Finally, the perspectives of strategies aimed to detect and modulate apoptosis of cardiomyocytes in hypertensive cardiomyopathy will be considered.

Collagen types I and III (Col I and Col III) are the major fibrillar collagens produced by fibroblasts and myofibroblasts in the adult heart. Fibrillar collagen of the heart provides the structural scaffolding for cardiomyocytes and coronary vessels and imparts cardiac tissue with physical properties that include stiffness and resistance to deformation. In addition, fibrillar collagen may also act as a link between contractile element of adjacent cardiomyocytes and as a conduit of information that is necessary for cell function. As in other organs, collagen turnover of normal adult heart results from the equilibrium between the synthesis and degradation of Col I and Col III. A number of factors have been described that may alter the balance in favor of either the synthesis (e.g., angiotensin II-ANG II-) or the degradation. Predominance of synthesis over degradation leads to increased Col I and Col III deposition or fibrosis that accompanies cardiac diseases such as hypertensive heart disease. Fibrosis alters myocardial structure and function and adversely afects the clinical outcome of hypertensive patients. Various lines of evidence suggest that besides hypertension, systemically and/or locally produced ANG II may participate in the development of hypertensive myocardial fibrosis via activation of ANG II type 1 receptors (AT(1)R). The potential clinical relevance of this possibility is linked to the ability of antihypertensive drugs such as angiotensin converting enzyme inhibitors (ACEIs) and AT(1)R antagonists (ARAs) to reverse myocardial fibrosis beyond their antihypertensive efficacy.

We investigated whether cardiac apoptosis is stimulated in the heart of hypertensive patients and whether angiotensin II plays a role in such alteration. The study was performed in 28 patients with essential hypertension and no evidence of either ischemic cardiomyopathy or heart failure. After randomization, 14 patients were assigned to losartan and 14 patients to amlodipine treatment. At baseline and after 12 months, right septal endomyocardial biopsies were performed, and the number of apoptotic nuclei was assessed by DNA end-labeling (TUNEL). In addition, immunostaining for the active form of caspase-3 was also performed to assess apoptosis. Compared with normotensive autopsied hearts, both cardiomyocyte and noncardiomyocyte apoptosis were increased ( P P