958 resultados para heart failure clinic


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Purpose: Diabetic myocardium is particularly vulnerable to develop heart failure in response to chronic stress conditions including hypertension or myocardial infarction. We have recently observed that angiotensin II (Ang II)-mediated downregulation of the fatty acid oxidation pathway favors occurrence of heart failure by myocardial accumulation of lipids (lipotoxicity). Because diabetic heart is exposed to high levels of circulating fatty acid, we determined whether insulin resistance favors development of heart failure in mice with Ang II-mediated myocardial remodeling.Methods: To study the combined effect of diabetes and Ang II-induced heart remodeling, we generated leptin-deficient/insulin resistant (Lepob/ob) mice with cardiac targeted overexpression of angiotensinogen (TGAOGN). Left ventricular (LV) failure was indicated by pulmonary congestion (lung weight/tibial length>+2SD of wild-type mice). Myocardial metabolism and function were assessed during in vitro isolated working heart perfusion.Results: Forty-eight percent of TGAOGN mice without insulin resistance exhibited pulmonary congestion at the age of 6 months associated with increased myocardial BNP expression (+375% compared with WT) and reduced LV power (developed pressure x cardiac output; -15%). The proportion of mice presenting heart failure was markedly increased to 71% in TGAOGN mice with insulin resistance (TGAOGN/Lepob/ob). TGAOGN/Lepob/ob mice with heart failure exhibited further increase of BNP compared with failing non-diabetic TGAOGN mice (+146%) and further reduction of cardiac power (-59%). Mice with insulin resistance alone (Lepob/ob) did not exhibit signs of heart failure or LV dysfunction. Myocardial fatty acid oxidation measured during in vitro perfusion was markedly increased in non-failing hearts from Lepob/ob mice (+380% compared with WT) and glucose oxidation decreased (-72%). In contrast, fatty acid and glucose oxidation did not differ from Lepob/ob mice in hearts from TGAOGN/Lepob/ob mice without heart failure. However, both fatty acid and glucose oxidation were markedly decreased (-47% and -48%, respectively, compared with WT/Lepob/+) in failing hearts from TGAOGN/Lepob/ob mice. Reduction of fatty acid oxidation was associated with marked reduction of protein expression of a number of regulatory enzymes implied in fatty acid oxidation.Conclusions: Insulin resistance favors the progression to heart failure during chronic exposure of the myocardium to Ang II. Our results are compatible with a role of Ang II-mediated downregulation of fatty acid oxidation, potentially promoting lipotoxicity.

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Background: Leptin is produced primarily by adipocytes. Although originally associated with the central regulation of satiety and energy metabolism, increasing evidence indicates that leptin may be an important factor for congestive heart faire (CHF). In the study, we aimed to test the hypothesis that leptin may influence CHF pathophysiology via a pathway of increasing body mass index (BMI). Methods: We studied 2,389 elderly participants aged 70 and older (M; 1161, F: 1228) without CHF and with serum leptin measures at the Health Aging, and Body Composition study. We analyzed the association between serum leptin level and risk of incident CHF using Cox hazard proportional regression models. Elevated leptin level was defined as more than the highest quartile (Q4) of leptin distribution in the total sample for each gender. Adjusted-covariates included demographic, behavior, lipid and inflammation variables (partially-adjusted models), and further included BMI (fully-adjusted models). Results: In a mean 9-year follow-up, 316 participants (13.2%) developed CHF. The partially-adjusted models indicated that men and women with elevated serum leptin levels (>=9.89 ng/ml in men and >=25 ng/ml in women) had significantly higher risks of developing CHF than those with leptin level of less than Q4. The adjusted hazard ratios (95%CI) for incident CHF was 1.49 (1.04 -2.13) in men and 1.71 (1.12 -2.58) in women. However, these associations became non-significant after adjustment for including BMI for each gender. The fully-adjusted hazard ratios (95%CI) were 1.43 (0.94 -2.18) in men and 1.24 (0.77-1.99) in women. Conclusion: Subjects with elevated leptin levels have a higher risk of CHF. The study supports the hypothesis that the influence of leptin level on risk of CHF may be through a pathway related to increasing BMI.

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Terminal heart failure can be the cause or the result of major dysfunctions of the organisms. Although, the outcome of the natural history is the same in both situations, it is of prime importance to differentiate the two, as only heart failure as the primary cause allows for successful mechanical circulatory support as bridge to transplantation or towards recovery. Various objective parameters allow for the establishment of the diagnosis of terminal heart failure despite optimal medical treatment. A cardiac index <2.0 l/min, and a mixed venous oxygen saturation <60%, in combination with progressive renal failure, should trigger a diagnostic work-up in order to identify cardiac defects that can be corrected or to list the patient for transplantation with/without mechanical circulatory support.

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BACKGROUND: American College of Cardiology/American Heart Association guidelines for the diagnosis and management of heart failure recommend investigating exacerbating conditions such as thyroid dysfunction, but without specifying the impact of different thyroid-stimulation hormone (TSH) levels. Limited prospective data exist on the association between subclinical thyroid dysfunction and heart failure events. METHODS AND RESULTS: We performed a pooled analysis of individual participant data using all available prospective cohorts with thyroid function tests and subsequent follow-up of heart failure events. Individual data on 25 390 participants with 216 248 person-years of follow-up were supplied from 6 prospective cohorts in the United States and Europe. Euthyroidism was defined as TSH of 0.45 to 4.49 mIU/L, subclinical hypothyroidism as TSH of 4.5 to 19.9 mIU/L, and subclinical hyperthyroidism as TSH <0.45 mIU/L, the last two with normal free thyroxine levels. Among 25 390 participants, 2068 (8.1%) had subclinical hypothyroidism and 648 (2.6%) had subclinical hyperthyroidism. In age- and sex-adjusted analyses, risks of heart failure events were increased with both higher and lower TSH levels (P for quadratic pattern <0.01); the hazard ratio was 1.01 (95% confidence interval, 0.81-1.26) for TSH of 4.5 to 6.9 mIU/L, 1.65 (95% confidence interval, 0.84-3.23) for TSH of 7.0 to 9.9 mIU/L, 1.86 (95% confidence interval, 1.27-2.72) for TSH of 10.0 to 19.9 mIU/L (P for trend <0.01) and 1.31 (95% confidence interval, 0.88-1.95) for TSH of 0.10 to 0.44 mIU/L and 1.94 (95% confidence interval, 1.01-3.72) for TSH <0.10 mIU/L (P for trend=0.047). Risks remained similar after adjustment for cardiovascular risk factors. CONCLUSION: Risks of heart failure events were increased with both higher and lower TSH levels, particularly for TSH ≥10 and <0.10 mIU/L.

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OBJECTIVES: The purpose of this study was to evaluate the association between inflammation and heart failure (HF) risk in older adults. BACKGROUND: Inflammation is associated with HF risk factors and also directly affects myocardial function. METHODS: The association of baseline serum concentrations of interleukin (IL)-6, tumor necrosis factor-alpha, and C-reactive protein (CRP) with incident HF was assessed with Cox models among 2,610 older persons without prevalent HF enrolled in the Health ABC (Health, Aging, and Body Composition) study (age 73.6 +/- 2.9 years; 48.3% men; 59.6% white). RESULTS: During follow-up (median 9.4 years), HF developed in 311 (11.9%) participants. In models controlling for clinical characteristics, ankle-arm index, and incident coronary heart disease, doubling of IL-6, tumor necrosis factor-alpha, and CRP concentrations was associated with 29% (95% confidence interval: 13% to 47%; p < 0.001), 46% (95% confidence interval: 17% to 84%; p = 0.001), and 9% (95% confidence interval: -1% to 24%; p = 0.087) increase in HF risk, respectively. In models including all 3 markers, IL-6, and tumor necrosis factor-alpha, but not CRP, remained significant. These associations were similar across sex and race and persisted in models accounting for death as a competing event. Post-HF ejection fraction was available in 239 (76.8%) cases; inflammatory markers had stronger association with HF with preserved ejection fraction. Repeat IL-6 and CRP determinations at 1-year follow-up did not provide incremental information. Addition of IL-6 to the clinical Health ABC HF model improved model discrimination (C index from 0.717 to 0.734; p = 0.001) and fit (decreased Bayes information criterion by 17.8; p < 0.001). CONCLUSIONS: Inflammatory markers are associated with HF risk among older adults and may improve HF risk stratification.

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OBJECTIVES: The goal of this study was to determine whether subclinical thyroid dysfunction was associated with incident heart failure (HF) and echocardiogram abnormalities. BACKGROUND: Subclinical hypothyroidism and hyperthyroidism have been associated with cardiac dysfunction. However, long-term data on the risk of HF are limited. METHODS: We studied 3,044 adults>or=65 years of age who initially were free of HF in the Cardiovascular Health Study. We compared adjudicated HF events over a mean 12-year follow-up and changes in cardiac function over the course of 5 years among euthyroid participants, those with subclinical hypothyroidism (subdivided by thyroid-stimulating hormone [TSH] levels: 4.5 to 9.9, >or=10.0 mU/l), and those with subclinical hyperthyroidism. RESULTS: Over the course of 12 years, 736 participants developed HF events. Participants with TSH>or=10.0 mU/l had a greater incidence of HF compared with euthyroid participants (41.7 vs. 22.9 per 1,000 person years, p=0.01; adjusted hazard ratio: 1.88; 95% confidence interval: 1.05 to 3.34). Baseline peak E velocity, which is an echocardiographic measurement of diastolic function associated with incident HF in the CHS cohort, was greater in those patients with TSH>or=10.0 mU/l compared with euthyroid participants (0.80 m/s vs. 0.72 m/s, p=0.002). Over the course of 5 years, left ventricular mass increased among those with TSH>or=10.0 mU/l, but other echocardiographic measurements were unchanged. Those patients with TSH 4.5 to 9.9 mU/l or with subclinical hyperthyroidism had no increase in risk of HF. CONCLUSIONS: Compared with euthyroid older adults, those adults with TSH>or=10.0 mU/l have a moderately increased risk of HF and alterations in cardiac function but not older adults with TSH<10.0 mU/l. Clinical trials should assess whether the risk of HF might be ameliorated by thyroxine replacement in individuals with TSH>or=10.0 mU/l.

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Contexte: La régurgitation mitrale (RM) est une maladie valvulaire nécessitant une intervention dans les cas les plus grave. Une réparation percutanée de la valve mitrale avec le dispositif MitraClip est un traitement sécuritaire et efficace pour les patients à haut risque chirurgical. Nous voulons évaluer les résultats cliniques et l'impact économique de cette thérapie par rapport à la gestion médicale des patients en insuffisance cardiaque avec insuffisance mitrale symptomatique. Méthodes: L'étude a été composée de deux phases; une étude d'observation de patients souffrant d'insuffisance cardiaque et de régurgitation mitrale traitée avec une thérapie médicale ou le MitraClip, et un modèle économique. Les résultats de l'étude observationnelle ont été utilisés pour estimer les paramètres du modèle de décision, qui a estimé les coûts et les avantages d'une cohorte hypothétique de patients atteints d'insuffisance cardiaque et insuffisance mitrale sévère traitée avec soit un traitement médical standard ou MitraClip. Résultats: La cohorte de patients traités avec le système MitraClip était appariée par score de propension à une population de patients atteints d'insuffisance cardiaque, et leurs résultats ont été comparés. Avec un suivi moyen de 22 mois, la mortalité était de 21% dans la cohorte MitraClip et de 42% dans la cohorte de gestion médicale (p = 0,007). Le modèle de décision a démontré que MitraClip augmente l'espérance de vie de 1,87 à 3,60 années et des années de vie pondérées par la qualité (QALY) de 1,13 à 2,76 ans. Le coût marginal était 52.500 $ dollars canadiens, correspondant à un rapport coût-efficacité différentiel (RCED) de 32,300.00 $ par QALY gagné. Les résultats étaient sensibles à l'avantage de survie. Conclusion: Dans cette cohorte de patients atteints d'insuffisance cardiaque symptomatique et d insuffisance mitrale significative, la thérapie avec le MitraClip est associée à une survie supérieure et est rentable par rapport au traitement médical.

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BACKGROUND: Fibroblast growth factor 9 (FGF9) is secreted from bone marrow cells, which have been shown to improve systolic function after myocardial infarction (MI) in a clinical trial. FGF9 promotes cardiac vascularization during embryonic development but is only weakly expressed in the adult heart. METHODS AND RESULTS: We used a tetracycline-responsive binary transgene system based on the α-myosin heavy chain promoter to test whether conditional expression of FGF9 in the adult myocardium supports adaptation after MI. In sham-operated mice, transgenic FGF9 stimulated left ventricular hypertrophy with microvessel expansion and preserved systolic and diastolic function. After coronary artery ligation, transgenic FGF9 enhanced hypertrophy of the noninfarcted left ventricular myocardium with increased microvessel density, reduced interstitial fibrosis, attenuated fetal gene expression, and improved systolic function. Heart failure mortality after MI was markedly reduced by transgenic FGF9, whereas rupture rates were not affected. Adenoviral FGF9 gene transfer after MI similarly promoted left ventricular hypertrophy with improved systolic function and reduced heart failure mortality. Mechanistically, FGF9 stimulated proliferation and network formation of endothelial cells but induced no direct hypertrophic effects in neonatal or adult rat cardiomyocytes in vitro. FGF9-stimulated endothelial cell supernatants, however, induced cardiomyocyte hypertrophy via paracrine release of bone morphogenetic protein 6. In accord with this observation, expression of bone morphogenetic protein 6 and phosphorylation of its downstream targets SMAD1/5 were increased in the myocardium of FGF9 transgenic mice. CONCLUSIONS: Conditional expression of FGF9 promotes myocardial vascularization and hypertrophy with enhanced systolic function and reduced heart failure mortality after MI. These observations suggest a previously unrecognized therapeutic potential for FGF9 after MI.

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Background—Probiotics are extensively used to promote gastrointestinal health and emerging evidence suggests that their beneficial properties can extend beyond the local environment of the gut. Here, we determined whether oral probiotic administration can alter the progression of post-infarction heart failure. Methods and Results—Rats were subjected to six weeks of sustained coronary artery occlusion and administered the probiotic Lactobacillus rhamnosus GR-1 or placebo in the drinking water ad libitum. Culture and 16s rRNA sequencing showed no evidence of GR-1 colonization or a significant shift in the composition of the cecal microbiome. However, animals administered GR-1 exhibited a significant attenuation of left ventricular hypertrophy based on tissue weight assessment as well as gene expression of atrial natriuretic peptide. Moreover, these animals demonstrated improved hemodynamic parameters reflecting both improved systolic and diastolic left ventricular function. Serial echocardiography revealed significantly improved left ventricular parameters throughout the six week follow-up period including a marked preservation of left ventricular ejection fraction as well as fractional shortening. Beneficial effects of GR-1 were still evident in those animals in which GR-1 was withdrawn at four weeks suggesting persistence of the GR-1 effects following cessation of therapy. Investigation of mechanisms showed a significant increase in the leptin to adiponectin plasma concentration ratio in rats subjected to coronary ligation which was abrogated by GR-1. Metabonomic analysis showed differences between sham control and coronary artery ligated hearts particularly with respect to preservation of myocardial taurine levels. Conclusions—The study suggests that probiotics offer promise as a potential therapy for the attenuation of heart failure.

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Three well-characterized mitogen-activated protein kinase (MAPK) subfamilies are expressed in rodent and rabbit hearts, and are activated by pathophysiological stimuli. We have determined and compared the expression and activation of these MAPKs in donor and failing human hearts. The amount and activation of MAPKs was assessed in samples from the left ventricles of 4 unused donor hearts and 12 explanted hearts from patients with heart failure secondary to ischaemic heart disease. Total MAPKs or dually phosphorylated (activated) MAPKs were detected by Western blotting and MAPK activities were measured by in gel kinase assays. As in rat heart, c-Jun N-terminal kinases (JNKs) were detected in human hearts as bands corresponding to 46 and 54 kDa; p38-MAPK(s) was detected as a band corresponding to approximately 40 kDa, and extracellularly regulated kinases, ERK1 and ERK2, were detected as 44- and 42-kDa bands respectively. The total amounts of 54 kDa JNK, p38-MAPK and ERK2 were similar in all samples, although 46-kDa JNK was reduced in the failing hearts. However, the mean activities of JNKs and p38-MAPK(s) were significantly higher in failing heart samples than in those from donor hearts (P<0.05). There was no significant difference in phosphorylated (activated) ERKs between the two groups. In conclusion, JNKs, p38-MAPK(s) and ERKs are expressed in the human heart and the activities of JNKs and p38-MAPK(s) were increased in heart failure secondary to ischaemic heart disease. These data indicate that JNKs and p38-MAPKs may be important in human cardiac pathology.

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Bacurau AV, Jardim MA, Ferreira JC, Bechara LR, Bueno CR Jr, Alba-Loureiro TC, Negrao CE, Casarini DE, Curi R, Ramires PR, Moriscot AS, Brum PC. Sympathetic hyperactivity differentially affects skeletal muscle mass in developing heart failure: role of exercise training. J Appl Physiol 106: 1631-1640, 2009. First published January 29, 2009; doi:10.1152/japplphysiol.91067.2008.-Sympathetic hyperactivity (SH) is a hallmark of heart failure (HF), and several lines of evidence suggest that SH contributes to HF-induced skeletal myopathy. However, little is known about the influence of SH on skeletal muscle morphology and metabolism in a setting of developing HF, taking into consideration muscles with different fiber compositions. The contribution of SH on exercise tolerance and skeletal muscle morphology and biochemistry was investigated in 3- and 7-mo-old mice lacking both alpha(2A)- and alpha(2C)-adrenergic receptor subtypes (alpha(2A)/alpha(2C)ARKO mice) that present SH with evidence of HF by 7 mo. To verify whether exercise training (ET) would prevent skeletal muscle myopathy in advanced-stage HF, alpha(2A)/alpha(2C)ARKO mice were exercised from 5 to 7 mo of age. At 3 mo, alpha(2A)/alpha(2C)ARKO mice showed no signs of HF and preserved exercise tolerance and muscular norepinephrine with no changes in soleus morphology. In contrast, plantaris muscle of alpha(2A)/alpha(2C)ARKO mice displayed hypertrophy and fiber type shift (IIA -> IIX) paralleled by capillary rarefaction, increased hexokinase activity, and oxidative stress. At 7 mo, alpha(2A)/alpha(2C)ARKO mice displayed exercise intolerance and increased muscular norepinephrine, muscular atrophy, capillary rarefaction, and increased oxidative stress. ET reestablished alpha(2A)/alpha(2C)ARKO mouse exercise tolerance to 7-mo-old wild-type levels and prevented muscular atrophy and capillary rarefaction associated with reduced oxidative stress. Collectively, these data provide direct evidence that SH is a major factor contributing to skeletal muscle morphological changes in a setting of developing HF. ET prevented skeletal muscle myopathy in alpha(2A)/alpha(2C)ARKO mice, which highlights its importance as a therapeutic tool for HF.

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Aim: Changes in skeletal muscle morphology and metabolism are associated with limited functional capacity in heart failure, which can be attenuated by neuromuscular electrical stimulation (ES). The purpose of the present study was to analyse the effects of ES upon GLUT-4 protein content, fibre structure and vessel density of the skeletal muscle in a rat model of HF subsequent to myocardial infarction. Methods: Forty-four male Wistar rats were assigned to one of four groups: sham (S), sham submitted to ES (S+ES), heart failure (HF) and heart failure submitted to ES (HF+ES). The rats in the ES groups were submitted to ES of the left leg during 20 days (2.5 kHz, once a day, 30 min, duty cycle 50%- 15 s contraction/15 s rest). After this period, the left tibialis anterior muscle was collected from all the rats for analysis. Results: HF+ES rats showed lower values of lung congestion when compared with HF rats (P = 0.0001). Although muscle weight was lower in HF rats than in the S group, thus indicating hypotrophy, 20 days of ES led to their recovery (P < 0.0001). In both groups submitted to ES, there was an increase in muscle vessel density (P < 0.04). Additionally, heart failure determined a 49% reduction in GLUT-4 protein content (P < 0.03), which was recovered by ES (P < 0.01). Conclusion: In heart failure, ES improves morphological changes and raises GLUT-4 content in skeletal muscle.

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Background/Aim. Granulocyte colony-stimulating factor (G-CSF) reduces myocardial injury and improves cardiac function after myocardial infarction (MI). We investigated the early alterations provided by G-CSF and the chronic repercussions in infarcted rats. Methods. Male Wistar rats (200-250g) received vehicle (MI) or G-CSF (MI-GCSF) (50 mu g/kg, sc) at 7, 3 and 1 days before MI surgery. Afterwards MI was produced and infarct size was measured 1 and 15 days after surgery. Expression of anti-and proapoptotic proteins was evaluated immediately before surgery. 24 hours after surgery, apoptotic nuclei were evaluated. Two weeks after MI, left ventricular (LV) function was evaluated, followed by in situ LV diastolic pressure-volume evaluation. Results. Infarct size was decreased by 1 day pretreatment before occlusion (36 +/- 2.8 vs. 44 +/- 2.1% in MI; P<0.05) and remained reduced at 15 days after infarction (28 +/- 2.2 vs. 36 +/- 1.4% in MI; P<0.05). G-CSF pretreatment increased Bcl-2 and Bcl-xL protein expression, but did not alter Bax in LV. Apoptotic nuclei were reduced by treatment (Sham: 0.46 +/- 0.42, MI: 15.5 +/- 2.43, MI-GCSF: 5.34 +/- 3.34%; P<0.05). Fifteen days after MI, cardiac function remained preserved in G-CSF pretreated rats. The LV dilation was reduced in MI-G-CSF group as compared to MI rats, being closely associated with infarct size. Conclusion. The early beneficial effects of G-CSF were essentials to preserve cardiac function at a chronic stage of myocardial infarction. Copyright (C) 2011 S. Karger AG, Basel

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In the Eplerenone Post-Acute Myocardial Infarction Heart Failure Efficacy and Survival Study ( n = 6632), eplerenone- associated reduction in all- cause mortality was significantly greater in those with a history of hypertension ( Hx- HTN). There were 4007 patients with Hx- HTN ( eplerenone: n = 1983) and 2625 patients without Hx- HTN ( eplerenone: n = 1336). Propensity scores for eplerenone use, separately calculated for patients with and without Hx- HTN, were used to assemble matched cohorts of 1838 and 1176 pairs of patients. In patients with Hx- HTN, all- cause mortality occurred in 18% of patients treated with placebo ( rate, 1430/ 10 000 person- years) and 14% of patients treated with eplerenone ( rate, 1058/ 10 000 person- years) during 2350 and 2457 years of follow- up, respectively ( hazard ratio [ HR]: 0.71; 95% CI: 0.59 to 0.85; P < 0.0001). Composite end point of cardiovascular hospitalization or cardiovascular mortality occurred in 33% of placebo-treated patients ( 3029/ 10 000 person- years) and 28% of eplerenone- treated patients (2438/10 000 person- years) with Hx- HTN ( HR: 0.82; 95% CI: 0.72 to 0.94; P = 0.003). In patients without Hx- HTN, eplerenone reduced heart failure hospitalization ( HR: 73; 95% CI: 0.55 to 0.97; P = 0.028) but had no effect on mortality ( HR: 0.91; 95% CI: 0.72 to 1.15; P = 0.435) or on the composite end point ( HR: 0.91; 95% CI: 0.76 to 1.10; P = 0.331). Eplerenone should, therefore, be prescribed to all of the post - acute myocardial infarction patients with reduced left ventricular ejection fraction and heart failure regardless of Hx- HTN.