Usefulness of B-type natriuretic peptide and C-reactive protein in predicting the presence or absence of left ventricular hypertrophy in patients with systemic hypertension

Cardiovascular Biomarkers: Lessons of the Past and Prospects for the Future

Cardiovascular diseases (CVDs) are a major healthcare burden on the population worldwide. Early detection of this disease is important in prevention and treatment to minimise morbidity and mortality. Biomarkers are a critical tool to either diagnose, screen, or provide prognostic information for pathological conditions. This review discusses the historical cardiac biomarkers used to detect these conditions, discussing their application and their limitations. Identification of new biomarkers have since replaced these and are now in use in routine clinical practice, but still do not detect all disease. Future cardiac biomarkers are showing promise in early studies, but further studies are required to show their value in improving detection of CVD above the current biomarkers. Additionally, the analytical platforms that would allow them to be adopted in healthcare are yet to be established. There is also the need to identify whether these biomarkers can be used for diagnostic, prognostic, or screening purposes, which will impact their implementation in routine clinical practice.

Centella asiatica (L.) Urb. Prevents Hypertension and Protects the Heart in Chronic Nitric Oxide Deficiency Rat Model

Background: Hypertension is a major risk factor for cardiovascular disease (CVD), which is the number one cause of global mortality. The potential use of natural products to alleviate high blood pressure has been demonstrated to exert a cardioprotective effect. Centella asiatica (L.) Urb. belongs to the plant family Apiaceae (Umbelliferae). It contains a high amount of triterpenoid and flavonoid that have antioxidant properties and are involved in the renin-angiotensin-aldosterone system which is an important hormonal system for blood pressure regulation. Objective: This study aimed to investigate the effects of C. asiatica ethanolic extract on blood pressure and heart in a hypertensive rat model, which was induced using oral N(G)-nitro-l-arginine methyl ester (l-NAME). Methods: Male Sprague-Dawley rats were divided into five groups and were given different treatments for 8 weeks. Group 1 only received deionized water. Groups 2, 4, and 5 were given l-NAME (40 mg/kg, orally). Groups 4 and 5 concurrently received C. asiatica extract (500 mg/kg, orally) and captopril (5 mg/kg, orally), respectively. Group 3 only received C. asiatica extract (500 mg/kg body weight, orally). Systolic blood pressure (SBP) was measured at weeks 0, 4, and 8, while serum nitric oxide (NO) was measured at weeks 0 and 8. At necropsy, cardiac and aortic malondialdehyde (MDA) contents, cardiac angiotensin-converting enzyme (ACE) activity, and serum level of brain natriuretic peptide (BNP) were measured. Results: After 8 weeks, the administrations of C. asiatica extract and captopril showed significant (p < 0.05) effects on preventing the elevation of SBP, reducing the serum nitric oxide level, as well as increasing the cardiac and aortic MDA content, cardiac ACE activity, and serum brain natriuretic peptide level. Conclusion: C. asiatica extract can prevent the development of hypertension and cardiac damage induced by l-NAME, and these effects were comparable to captopril.

KLF2 regulates neutrophil activation and thrombosis in cardiac hypertrophy and heart failure progression

It is widely recognized that inflammation plays a critical role in cardiac hypertrophy and heart failure. However, clinical trials targeting cytokines have shown equivocal effects, indicating the need for a deeper understanding of the precise role of inflammation and inflammatory cells in heart failure. Leukocytes from human subjects and a rodent model of heart failure were characterized by a marked reduction in expression of Klf2 mRNA. Using a mouse model of angiotensin II–induced nonischemic cardiac dysfunction, we showed that neutrophils played an essential role in the pathogenesis and progression of heart failure. Mechanistically, chronic angiotensin II infusion activated a neutrophil KLF2/NETosis pathway that triggered sporadic thrombosis in small myocardial vessels, leading to myocardial hypoxia, cell death, and hypertrophy. Conversely, targeting neutrophils, neutrophil extracellular traps (NETs), or thrombosis ameliorated these pathological changes and preserved cardiac dysfunction. KLF2 regulated neutrophil activation in response to angiotensin II at the molecular level, partly through crosstalk with HIF1 signaling. Taken together, our data implicate neutrophil-mediated immunothrombotic dysregulation as a critical pathogenic mechanism leading to cardiac hypertrophy and heart failure. This neutrophil KLF2-NETosis-thrombosis mechanism underlying chronic heart failure can be exploited for therapeutic gain by therapies targeting neutrophils, NETosis, or thrombosis.

Association between serum level of C-reactive protein and risk of cardiovascular events based on cohort studies

Although the association between serum level of C-reactive protein (CRP) and risk of cardiovascular events (CVEs) has been reported, the comprehensive assessment of the quantitative association of CRP level with risk of CVEs has not been reported. Our meta-analysis aims to quantitatively evaluate the association of CRP level and risk of CVEs. We searched PubMed and Embase databases for articles published up to December 6, 2019. Studies with data on men and women, different types of CVEs and multiple cohorts within a study were treated as independent studies. Generalized least-squares regression models were used to assess the quantitative association between CRP level and risk of CVEs. Restricted cubic splines were used to model the possible linear association between CRP and CVEs. We included 36 articles (60 studies; 227,715 participants) in the analysis. The pooled relative risks (RRs) of high versus low CRP level for cardiovascular disease (CVD), stroke and coronary heart disease (CHD) were 1.64 (95% confidence interval [CI], 1.49-1.82), 1.46 (95% CI, 1.35-1.58), and 1.55 (95% CI, 1.47-1.63), respectively. A linear association was found between CRP level and CVD (P = 0.429), stroke (P = 0.940), and CHD (P = 0.931); with each 1-mg/L increase in CRP level, the pooled RRs for CVD, stroke, and CHD were 1.18 (95% CI, 1.12-1.24), 1.07 (95% CI, 1.04-1.09), and 1.12 (95% CI, 1.08-1.16), respectively. This meta-analysis suggests that risk of CVEs increases with increasing serum CRP level.

Implications of the ACC/AHA risk score for prediction of heart failure: the Rotterdam Study

BACKGROUND

Despite the growing burden of heart failure (HF), there have been no recommendations for use of any of the primary prevention models in the existing guidelines. HF was also not included as an outcome in the American College of Cardiology/American Heart Association (ACC/AHA) risk score.

METHODS

Among 2743 men and 3646 women aged ≥ 55 years, free of HF, from the population-based Rotterdam Study cohort, 4 Cox models were fitted using the predictors of the ACC/AHA, ARIC and Health-ABC risk scores. Performance of the models for 10-year HF prediction was evaluated. Afterwards, performance and net reclassification improvement (NRI) for adding NT-proBNP to the ACC/AHA model were assessed.

RESULTS

During a median follow-up of 13 years, 429 men and 489 women developed HF. The ARIC model had the highest performance [c-statistic (95% confidence interval [CI]): 0.80 (0.78; 0.83) and 0.80 (0.78; 0.83) in men and women, respectively]. The c-statistic for the ACC/AHA model was 0.76 (0.74; 0.78) in men and 0.77 (0.75; 0.80) in women. Adding NT-proBNP to the ACC/AHA model increased the c-statistic to 0.80 (0.78 to 0.83) in men and 0.81 (0.79 to 0.84) in women. Sensitivity and specificity of the ACC/AHA model did not drastically change after addition of NT-proBNP. NRI(95%CI) was - 23.8% (- 19.2%; - 28.4%) in men and - 27.6% (- 30.7%; - 24.5%) in women for events and 57.9% (54.8%; 61.0%) in men and 52.8% (50.3%; 55.5%) in women for non-events.

CONCLUSIONS

Acceptable performance of the model based on risk factors included in the ACC/AHA model advocates use of this model for prediction of HF risk in primary prevention setting. Addition of NT-proBNP modestly improved the model performance but did not lead to relevant discrimination improvement in clinical risk reclassification.

Inflammation and ventricular-vascular coupling in hypertensive patients with metabolic syndrome

BACKGROUND AND AIMS

Metabolic syndrome (MetS) is currently considered to raise the risk for type 2 diabetes and cardiovascular events. It has been suggested that part of this risk excess may be due to a cluster of additional factors associated with MetS. We aimed to investigate the role of inflammation on the ventricular-vascular coupling in patients with MetS.

METHODS AND RESULTS

We enrolled a total of 227 hypertensive patients (106 with MetS and 121 without MetS) matched for age and gender. Aortic pulse wave velocity (aPWV), intima-media thickness (IMT) and high sensitivity C-reactive protein (CRP) increased according to the number of MetS components. Patients with MetS showed increased aPWV (11.5 ± 3.7 vs. 10.3 ± 2.5 m/s, P = 0.03) compared with controls. In a model adjusted for age, sex, heart rate and mean blood pressure, aPWV resulted increased in patients with CKD (beta 1.29 m/s, 95%CI 0.61-1.96 m/s, P < 0.001) and MetS (beta 0.89 m/s, 95%CI 0.28-1.51 m/s, P = 0.005). After additional adjustment for CRP and IMT, the slope of aPWV was respectively reduced by 16% and 62%, suggesting that inflammation and intima-media thickening could contribute to aortic stiffening in patients with MetS. In these patients, aPWV was also associated with left-ventricular mass index (beta 0.79 g/m^2.7, 95%CI 0.05-1.52 g/m^2.7, P = 0.05).

CONCLUSION

MetS is characterized by an inflammation-dependent acceleration in cardiovascular ageing. This pattern of pathophysiological abnormalities may contribute to amplify the burden of cardiovascular risk in patients with MetS.

Phenomapping for the Identification of Hypertensive Patients with the Myocardial Substrate for Heart Failure with Preserved Ejection Fraction

We sought to evaluate whether unbiased machine learning of dense phenotypic data ("phenomapping") could identify distinct hypertension subgroups that are associated with the myocardial substrate (i.e., abnormal cardiac mechanics) for heart failure with preserved ejection fraction (HFpEF). In the HyperGEN study, a population- and family-based study of hypertension, we studied 1273 hypertensive patients utilizing clinical, laboratory, and conventional echocardiographic phenotyping of the study participants. We used machine learning analysis of 47 continuous phenotypic variables to identify mutually exclusive groups constituting a novel classification of hypertension. The phenomapping analysis classified study participants into 2 distinct groups that differed markedly in clinical characteristics, cardiac structure/function, and indices of cardiac mechanics (e.g., phenogroup #2 had a decreased absolute longitudinal strain [12.8 ± 4.1 vs. 14.6 ± 3.5%] even after adjustment for traditional comorbidities [p < 0.001]). The 2 hypertension phenogroups may represent distinct subtypes that may benefit from targeted therapies for the prevention of HFpEF.

The Relationship Between High-Sensitivity C-Reactive Protein Levels and Left Ventricular Hypertrophy in Patients With Newly Diagnosed Hypertension

The authors aimed to evaluate the relationship between high-sensitivity C-reactive protein (hs-CRP) and presence of left ventricular hypertrophy and diastolic dysfunction in patients with hypertension. A total of 95 newly diagnosed hypertensive patients (mean age, 54±10 years) and 20 controls were included in this study. Patients were divided into four groups according to relative wall thickness as normal, concentric remodeling, concentric, and eccentric hypertrophy. hs-CRP was measured in all patients and serum hs-CRP level was shown to be increased in patients with hypertension compared with controls (0.57 mg/dL vs 0.25 mg/dL, respectively; P<.001). The hs-CRP level was highest in patients with concentric hypertrophy. When compared with controls, serum hs-CRP level was significantly higher in patients with concentric remodeling (0.61±0.3 mg/dL vs 0.43±0.5 mg/dL, P<.030) and concentric hypertrophy (0.69±0.3 mg/dL vs 0.43±0.5 mg/dL, P<.032). The present study shows that serum hs-CRP is significantly associated with left ventricular diastolic function and concentric hypertrophy in patients with hypertension.

Relationship between high-sensitivity cardiac troponin I and blood pressure among young and healthy adults

BACKGROUND

The aim of this study was to evaluate the relationship of cardiac troponin (cTn) levels with conventional and ambulatory blood pressure (BP) in young and healthy adults.

METHODS

We performed a population based cross-sectional analysis among 2,072 young and healthy adults aged 25-41 years free of cardiovascular disease and diabetes mellitus. cTnI was measured using a highly sensitive (hs) assay. The relationships of high sensitivity cardiac tropononin I (hs-cTnI) with office and 24-hour BP were assessed using multivariable regression analyses.

RESULTS

Median age was 37 years and 975 (47%) participants were male. hs-cTnI levels were detectable in 2,061 (99.5%) individuals. Median (interquartile range) hs-cTnI levels were 0.98 (0.71; 1.64) ng/L among men and 0.48 (0.33; 0.71) ng/L among women. Systolic BP, but not diastolic BP, gradually increased across hs-cTnI quartiles (118, 120, 121, and 122 mm Hg for conventional BP; P = 0.0002; 122, 123, 124, and 124 mm Hg for 24-hour BP, P = 0.0001). In multivariable linear regression analyses, the β estimates for systolic BP per 1-unit increase in log transformed hs-cTnI were 2.52 for conventional BP (P = 0.0001); 2.75 for 24-hour BP (P < 0.0001); 2.71 and 2.41 (P < 0.0001 and P = 0.0002) for day and nighttime BP, respectively. There was a significant relationship between hs-cTnI and the Sokolow-Lyon Index (odds ratio (95% confidence interval): 2.09 (1.37; 3.18), P < 0.001).

CONCLUSION

Using a hs assay, hs-cTnI was detectable in virtually all participants of a young and healthy population. hs-cTnI was independently associated with systolic BP and left ventricular hypertrophy.

Urinary type IV collagen is related to left ventricular diastolic function and brain natriuretic peptide in hypertensive patients with prediabetes

AIM

Urinary type IV collagen is an early biomarker of diabetic nephropathy. Concomitant prediabetes (the early stage of diabetes) was associated with left ventricular (LV) diastolic dysfunction and increased brain natriuretic peptide (BNP) in hypertensive patients. We hypothesized that urinary type IV collagen may be related to these cardiac dysfunctions.

METHODS

We studied hypertensive patients with early prediabetes (HbA1c <5.7% and fasting glucose >110, n=18), those with prediabetes (HbA1c 5.7-6.4, n=98), and those with diabetes (HbA1c>6.5 or on diabetes medications, n=92). The participants underwent echocardiography to assess left atrial volume/body surface area (BSA) and the ratio of early mitral flow velocity to mitral annular velocity (E/e'). Left ventricular diastolic dysfunction (LVDD) was defined if patients had E/e'≥15, or E/e'=9-14 accompanied by left atrial volume/BSA≥32ml/mm(2). Urinary samples were collected for type IV collagen and albumin, and blood samples were taken for BNP and HbA1c.

RESULTS

Urinary type IV collagen and albumin increased in parallel with the deterioration of glycemic status. In hypertensive patients with prediabetes, subjects with LVDD had higher levels of BNP and urinary type IV collagen than those without LVDD. In contrast, in hypertensive patients with diabetes, subjects with LVDD had higher urinary albumin and BNP than those without LVDD. Urinary type IV collagen correlated positively with BNP in hypertensive patients with prediabetes, whereas it correlated with HbA1c in those with diabetes.

CONCLUSIONS

In hypertensive patients with prediabetes, urinary type IV collagen was associated with LV diastolic dysfunction and BNP.

Cardiovascular risk stratification with plasma B-type natriuretic peptide levels in a community-based hypertensive cohort

Few reports have examined the utility of plasma B-type natriuretic peptide (BNP) testing for cardiovascular (CV) risk stratification in real-world hypertensive subjects. Subjects of the study were community-based hypertensive patients (n = 5,865). The CV event rate within each BNP quartile was estimated, and a Cox regression model was used to determine the relative hazard ratio (HR) among the quartiles. Furthermore, to determine the usefulness of BNP as a biomarker in combination with the Framingham risk score (FRS), the predictive abilities in terms of area under the curve of receiver operating characteristic analysis, net reclassification improvement, and integrated discrimination improvement indices were determined. The mean follow-up duration was 5.6 years. The highest quartile showed a significantly higher rate of CV events compared with the lower quartiles (p <0.001). After adjustment for established CV risk factors, the HR for CV events increased significantly according to the quartile (p value for trend <0.03), and the HR for the highest quartile was significantly elevated compared with the lowest quartile (HR 1.59, 95% confidence interval 1.16 to 2.19). The predictive abilities of BNP in terms of sensitivity and specificity for CV events were comparable with those of FRS. When BNP was added to an FRS-only model, the predictive abilities in terms of area under receiver operating characteristic curve, net reclassification improvement, and integrated discrimination improvement were significantly increased (all; p <0.001). Elevated BNP levels are thus a useful biomarker for CV risk stratification in unselected real-world hypertensive subjects. Adding BNP to an established CV risk score improves the predictive ability in this cohort.

An Internet-Based Counseling Intervention With Email Reminders that Promotes Self-Care in Adults With Chronic Heart Failure: Randomized Controlled Trial Protocol

Background

Chronic heart failure (CHF) is a public health priority. Its age-standardized prevalence has increased over the past decade. A major challenge for the management of CHF is to promote long-term adherence to self-care behaviors without overtaxing available health care resources. Counseling by multidisciplinary health care teams helps to improve adherence to self-care behaviors and to reduce the rate of death and hospitalization. In the absence of intervention, adherence to self-care is below recommended standards.

Objective

This trial aims to establish and evaluate a Canadian e-platform that will provide a core, standardized protocol of behavioral counseling and education to facilitate long-term adherence to self-care among patients with CHF.

Methods

Canadian e-Platform to Promote Behavioral Self-Management in Chronic Heart Failure (CHF-CePPORT) is a multi-site, double blind, randomized controlled trial with a 2 parallel-group (e-Counseling + Usual Care vs e-Info Control + Usual Care) by 3 assessments (baseline, 4-, and 12-month) design. We will identify subjects with New York Heart Association Class II or III systolic heart failure from collaborating CHF clinics and then recruit them (n=278) by phone. Subjects will be randomized in blocks within each site (Toronto, Montreal, and Vancouver). The primary outcome will be improved quality of life, defined as an increased number of subjects with an improvement of ≥5 points on the summary score of the Kansas City Cardiomyopathy Questionnaire. We will also assess the following secondary outcomes: (1) diet habits, depression, anxiety, smoking history, stress level, and readiness for change using self-report questionnaires, (2) physical activity level, current smoking status, and vagal-heart rate modulation by physiological tests, and (3) exercise capacity, prognostic indicators of cardiovascular functioning, and medication adherence through medical chart review. The primary outcome will be analyzed using generalized estimation equations with repeated measures on an intention-to-treat basis. Secondary outcomes will be analyzed using repeated-measures linear mixed models with a random effects intercept. All significant main effects or interactions in the statistical models will be followed up with post hoc contrasts using a Bonferroni correction with a 2-sided statistical significance criterion of P<.05.

Results

This 3.5-year, proof-of-principle trial will establish the e-infrastructure for a pan-Canadian e-platform for CHF that is comprised of a standardized, evidence-based protocol of e-Counseling.

Conclusions

CHF-CePPORT is designed to improve long-term adherence to self-care behaviors and quality of life among patients with CHF. It will demonstrate a distinct Canadian initiative to build capacity for preventive eHealth services for patients with CHF.

Trial Registration

ClinicalTrials.gov NCT01864369; http://clinicaltrials.gov/ct2/show/NCT01864369 (Archived by WebCite at http://www.webcitation.org/6Iiv6so7E).

Nocturnal Blood Pressure Pattern Affects Left Ventricular Remodeling and Late Gadolinium Enhancement in Patients with Hypertension and Left Ventricular Hypertrophy

Background

Left ventricular hypertrophy (LVH) is an independent predictor of cardiac mortality, regardless of its etiology. Previous studies have shown that high nocturnal blood pressure (BP) affects LV geometry in hypertensive patients. It has been suggested that continuous pressure overload affects the development of LVH, but it is unknown whether persistent pressure influences myocardial fibrosis or whether the etiology of LVH is associated with myocardial fibrosis. Comprehensive cardiac magnetic resonance (CMR) including the late gadolinium enhancement (LGE) technique can evaluate both the severity of changes in LV geometry and myocardial fibrosis. We tested the hypothesis that the nocturnal non-dipper BP pattern causes LV remodeling and fibrosis in patients with hypertension and LVH.

Methods

Forty-seven hypertensive patients with LVH evaluated by echocardiography (29 men, age 73.0±10.4 years) were examined by comprehensive CMR and 24-h ambulatory blood pressure monitoring (ABPM).

Results and Conclusions

Among the 47 patients, twenty-four had nocturnal non-dipper BP patterns. Patients with nocturnal non-dipper BP patterns had larger LV masses and scar volumes independent of etiologies than those in patients with dipper BP patterns (p = 0.035 and p = 0.015, respectively). There was no significant difference in mean 24-h systolic BP between patients with and without nocturnal dipper BP patterns (p = 0.367). Among hypertensive patients with LVH, the nocturnal non-dipper blood pressure pattern is associated with both LV remodeling and myocardial fibrosis independent of LVH etiology.

The diagnostic utility of brain natriuretic peptide in heart failure patients presenting with acute dyspnea: a meta-analysis

Heart failure with normal ejection fraction (HFNEF) accounts for approximately 50% of heart failure (HF) cases. To establish the utility of brain natriuretic peptide (BNP) in differentiating HF-related severe dyspnea from non-HF-related acute dyspnea, we used an estimation formula (eF) that was obtained from a series of three meta-regressions. We selected 60 out of 2721 case-control and follow-up studies that were published from 1998 to 2010. The heart failure levels (HFLs) were assessed using the New York Heart Association (NYHA) criteria. Random-effects meta-regression analyses of the natural logarithm (ln) of the BNP odds ratio (OR) were performed on the HFLs. The ln of the median BNP values (lnmBNP) was meta-regressed over the laboratory method (LM). A third meta-regression was performed on the HFLs to account for only the lnmBNP in the homogeneous LM subgroups. To determine the eF, the data from the diseased and control subjects were combined. The Bland-Altman method was used to detect eF bias. The overall BNP(OR) in the subgroup with severe HF was 35. The lnmBNP analysis showed that LM was a significant heterogeneity factor in the meta-regression (slope −0.38; CI −0.59 to −0.16). The meta-regression of lnmBNP on the HFL resulted in the following calculation for eF: estimated HFL (eHFL)=(lnmBNP–3.157)/0.886. The Bland-Altman test revealed no significant difference (0.0997; 95% CI −2.84 to 3.06) between HFL and eHFL. The severe eHFL showed a 78% accuracy. Based on the eF obtained from this meta-analysis, the BNP outcomes were shown to reliably diagnose severe dyspnea in HF and differentiate this condition from non-HF acute dyspnea.

Combined use of high-sensitivity C-reactive protein and apolipoprotein B/apolipoprotein A-1 ratio prior to elective coronary angiography and oral glucose tolerance tests

OBJECTIVES

The study aimed to investigate the predictive value of the combination of high-sensitivity C-reactive protein (hs-CRP) and apolipoprotein B (apoB)/apoA-1 ratio for the outcomes of coronary angiography (CAG), echocardiography and oral glucose tolerance tests (OGTTs).

DESIGN AND METHODS

Hs-CRP, apoB, apoA-1, and the profiles of CAG, echocardiography and OGTTs as well as traditional risk factors were measured in 1757 cardiology patients.

RESULTS

Hs-CRP or apoB/apoA-1 ratio was significantly correlated with the presence and severity of angiographic profiles, the levels of left ventricular (LV) ejection fraction, LV mass and LV mass index, and the presence of abnormal glucose metabolism. The combination of hs-CRP and apoB/apoA-1 ratio had greater correlation with abnormal glucose metabolism than its individual components in patients with normal fasting glucose, and was an independent predictor for coronary artery disease.

CONCLUSIONS

The combination of hs-CRP and apoB/apoA-1 ratio may be a strong predictor for coronary artery disease and abnormal glucose metabolism.

Natriuretic peptides: ready for prime-time in hypertension?

Over the past years, natriuretic peptides have been recognised not only as important contributors to cardiovascular regulation but also as valuable markers in overt cardiac disease, including heart failure or coronary disease. More recently, these markers have shown their ability to detect preclinical cardiac alterations in different settings. In this respect, natriuretic peptides offer a new perspective for risk stratification in hypertension. They are correlated to various features of cardiac remodelling provoked by hypertension. They also depend on vascular properties, including blood pressure level and aortic stiffness. In addition to being integrative markers of cardiovascular alterations, several studies have shown their value in predicting all-cause mortality or cardiovascular mortality and morbidity in the general population. At least three consistent studies are now available in hypertension also showing this prognostic value. This performance, together with the ease of measurement, low cost and widespread availability, should prompt the wide use of natriuretic peptides for risk stratification in hypertension, at least in patients with normal electrocardiography, but also in most hypertensive patients.

N-Terminal Pro-Brain Natriuretic Peptide

See Editorial Commentary, pp 670–671

Natriuretic peptides are controregulatory hormones associated with cardiac remodeling, namely, left ventricular hypertrophy and systolic/diastolic dysfunction. We intended to address the prognostic value of N-terminal pro-brain natriuretic peptide (NT-proBNP) in hypertension. We prospectively studied the relationship between plasma NT-proBNP and all-cause mortality in 684 hypertensive patients with no history or symptoms of heart failure referred for hypertension workup in our institution from 1998 to 2008. After a mean duration of 5.7 years, we observed 40 deaths (1.04 deaths per 100 patients per year). After adjustment for traditional cardiovascular risk factors, including ambulatory blood pressure and serum creatinine, the risk for all-cause mortality more than doubled with each increment of 1 log NT-proBNP (hazard ratio: 2.33 [95% CI: 1.36 to 3.96]). The risk of death of patients with plasma NT-proBNP ≥133 pg/mL (third tertile of the distribution) was 3.3 times that of patients with values <50.8 pg/mL (first tertile; hazard ratio: 3.30 [95% CI: 0.90 to 12.29]). This predictive value was independent of, and superior to, that of 2 ECG indexes of left ventricular hypertrophy, the Sokolov-Lyon index and the amplitude of the R wave in lead aVL. In addition, it persisted in patients without ECG left ventricular hypertrophy, which allowed refining risk stratification in this relatively low-risk patient category. In this large sample of hypertensive patients, plasma NT-proBNP appeared as a strong prognostic marker. This performance, together with the ease of measurement, low cost, and widespread availability of NT-proBNP test kits, should prompt a wide use of this marker for risk stratification in hypertension.

Association between echocardiographic parameters and brain natriuretic peptide levels in treated hypertensive patients

We examined which echocardiographic parameter correlated best with plasma brain natriuteric peptide (BNP) levels in treated hypertensive patients. Enrolled in the study were 122 treated hypertensive patients (70 ± 9 y). The left ventricular mass index and left atrial dimension (LAD) were measured using echocardiography as indexes of left ventricular hypertrophy and left atrial enlargement, respectively. Among all the echocardiographic parameters, LAD correlated best with BNP (r = 0.343, p < 0.001). Stepwise regression analysis showed that LAD (β coefficient = 0.513, p < 0.001) was independently associated with BNP. Left atrial enlargement, rather than left ventricular hypertrophy, may be clinically useful for predicting elevated BNP levels in treated hypertensive patients.

Natriuretic peptides (BNP and NT-proBNP): measurement and relevance in heart failure

For patients presenting with acute dyspnea, an incorrect diagnosis could increase the mortality risk. When used in the evaluation of patients with acute symptoms, brain natriuretic peptide and N-terminal pro-brain natriuretic peptide (BNP and NT-proBNP, respectively) testing is highly sensitive for the diagnosis or exclusion of acute or chronic decompensated heart failure (HF). It has been demonstrated that BNP and proBNP levels can facilitate diagnosis and guide HF therapy. Natriuretic peptide (NP) levels are strictly related with HF severity; they are particularly increased in more advanced New York Heart Association (NYHA) classes and in patients with poor outcome. Therefore elevated NP levels were found to correlate with the severity of left ventricular systolic dysfunction, right ventricular dysfunction and pressures, and left ventricular filling alterations. However, the optimal use of NP determination agrees with patient history, physical examination, and all other diagnostic tools. There are some clinical conditions (ie, obesity, renal insufficiency anemia) for which the NP measurement is not diagnostic. Algorithm building taking into consideration all clinical and echocardiographic parameters, as well as NP measurements, may lead to the earlier identification and better risk stratification of patients with chronic HF, independently from etiology.

Impaired flow-mediated vasodilatation is associated with increased left ventricular mass in a multiethnic population. The Northern Manhattan Study

BACKGROUND

Increased left ventricular (LV) mass and endothelial dysfunction are important risk factors for cardiovascular mortality and morbidity. However, it is not clear whether endothelial dysfunction is associated with increased LV mass. We tested the hypothesis that impaired flow-mediated vasodilatation (FMD) is associated with increased LV mass in a population-based multiethnic cohort.

METHODS

As a part of the Northern Manhattan Study (NOMAS), we performed two-dimensional echocardiography and FMD assessment during reactive hyperemia by high-resolution ultrasonography in 867 stroke-free community participants. LV mass was calculated according to an established method. LV hypertrophy was defined as the 90th percentile of sex-specific LV mass indexed for body surface area among normal subjects. Multivariable models were used to test the association of FMD with LV mass.

RESULTS

In multiple linear regression analysis adjusting for age, sex, body mass index, systolic blood pressure, antihypertensive medications, low-density lipoprotein cholesterol, diabetes, smoking, hematocrit, and race-ethnicity, FMD was inversely associated with LV mass (beta = -1.21 +/- 0.56, P = 0.03). The association persisted after further adjustment for any component of blood pressure (systolic, mean, and pulse pressure). In univariate logistic regression analysis, each 1% decrease in FMD was associated with an 8% higher risk of LV hypertrophy (odds ratio 1.08, 95% confidence interval 1.03-1.13 per each FMD point P < 0.01).

CONCLUSIONS

Impaired FMD is associated with LV mass, independent of other factors associated with increased LV mass. Endothelial dysfunction might be a potential risk factor for LV hypertrophy.

C-reactive Protein among Community-Dwelling Hypertensives on Single-agent Antihypertensive Treatment

BACKGROUND

C-reactive protein is a predictor of adverse cardiovascular outcomes. The effect of antihypertensive therapy on C-reactive protein levels is largely unknown.

METHOD

We undertook a cross-sectional study of CRP levels among participants with primary hypertension on single-agent anti-hypertensive therapy in the community-based biracial Genetic Epidemiology Network of Arteriopathy cohort. Linear regression models were used to assess the association of anti-hypertensive medication class with log-transformed C-reactive protein after adjustment for age, gender, ethnicity, body mass index, smoking, diabetes, HMG-Co-A reductase inhibitor use, achieved blood pressure control (<140/90 mmHg), serum creatinine and urine albumin-to-creatinine ratios.

RESULTS

There were 662 participants in the cohort taking single-agent therapy for hypertension. Median C-reactive protein levels differed across participants: 0.40 mg/dL for those on diuretics, 0.34 mg/dL on calcium channel blockers, 0.25 mg/dL on beta blockers and 0.27 mg/dL on renin-angiotensin-aldosterone system inhibitors (p<0.001). With multivariable adjustment, the group on renin-angiotensin-aldosterone system inhibitors had a 20% lower mean CRP on average than the group on diuretics (p=0.044), differences between other medication classes were not apparent. Heart rate had a strong association with C-reactive protein (p < 0.001).

CONCLUSIONS

Antihypertensive medication class may influence inflammation, particularly in patients on RAAS inhibitors.

Serial bedside B-type natriuretic peptide strongly predicts prognosis in acute coronary syndrome independent of echocardiographic abnormalities

BACKGROUND

Elevated levels of B-type natriuretic peptide (BNP) are associated with adverse clinical outcomes in acute coronary syndrome (ACS), but several questions remain outstanding. Firstly, it has not yet been determined whether an additional BNP sample at 7 weeks post ACS would enhance risk prediction. Secondly, we assessed whether the prognostic potential of BNP in ACS could be explained by echocardiographic abnormalities such as left ventricular hypertrophy (LVH).

METHODS

We measured bedside BNP levels in 443 consecutive patients presenting with ACS and at 7 weeks outpatient follow-up. Main outcome measure was either all-cause mortality, readmission with ACS, or congestive heart failure) at 10 months from presentation.

RESULTS

Of the 443 patients, 120 patients presented with ST-elevation myocardial infarction (27%). There were 90 cardiovascular (CV) events at 10 months. Adjusting for age, sex, hypertension, diabetes mellitus, smoking status, renal dysfunction, left ventricular ejection fraction, and echocardiographic LVH elevated near patient BNP levels (>80 pg/mL) were still associated with subsequent CV events when measured on admission (adjusted relative risk [RR] 2.63 [95% CI 1.34-5.19)] and also at 7 weeks post ACS (adjusted RR 4.12 [95% CI 1.58-10.72]). Patients with persistent BNP elevation at 7 weeks were also at an increased risk of CV events compared to those with an initial high BNP which then fell (unadjusted RR 4.04 [95% CI 1.24-13.15]).

CONCLUSION

In ACS, bedside BNP levels predict CV events at 10 months, independent of many echocardiographic abnormalities including LVH. Furthermore, our study suggests that an additional 7 weeks post ACS BNP enhances risk stratification over and above a one-off high BNP at baseline.

Relations of biomarkers representing distinct biological pathways to left ventricular geometry

BACKGROUND

Several biological pathways are activated concomitantly during left ventricular (LV) remodeling. However, the relative contribution of circulating biomarkers representing these distinct pathways to LV geometry is unclear.

METHODS AND RESULTS

We evaluated 2119 Framingham Offspring Study participants (mean age, 57 years; 57% women) who underwent measurements of biomarkers of inflammation (C-reactive protein), hemostasis (fibrinogen and plasminogen activator inhibitor-1), neurohormonal activation (B-type natriuretic peptide), and renin-angiotensin-aldosterone system (aldosterone and renin modeled as a ratio [ARR]) and echocardiography at a routine examination. LV geometry was defined on the basis of sex-specific distributions of LV mass (LVM) and relative wall thickness (RWT): normal (LVM and RWT <80th percentile), concentric remodeling (LVM <80th percentile but RWT >or=80th percentile), eccentric hypertrophy (LVM >or=80th percentile but RWT <80th percentile), and concentric hypertrophy (LVM and RWT >or=80th percentile). We related the biomarker panel to LV geometry using polytomous logistic regression adjusting for clinical covariates and used backwards elimination to identify a parsimonious set of biomarkers associated with LV geometry. Modeled individually, C-reactive protein, fibrinogen, plasminogen activator inhibitor-1, and ARR were related to LV geometry (P<0.01). In multivariable analyses, the biomarker panel was significantly related to altered LV geometry (P<0.0001). On backwards elimination, logARR alone was significantly and positively associated with eccentric (odds ratio per SD increment, 1.20; 95% confidence interval, 1.05 to 1.37) and concentric LV hypertrophy (odds ratio per SD increment, 1.29; 95% confidence interval, 1.06 to 1.58).

CONCLUSIONS

Our cross-sectional observations on a large community-based sample identified ARR as a key correlate of concentric and eccentric LV hypertrophy, consistent with a major role for the renin-angiotensin-aldosterone system in LV remodeling.

Serum markers of systemic right ventricular function and exercise performance

The right ventricle, which faces systemic pressure due to congenital heart disease, often develops premature systolic dysfunction. Cardiac hormones might be useful to identify patients with such systolic dysfunction. This prospective study investigated the relationship of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels with right ventricular ejection fraction (RVEF) and exercise performance in patients with a systemic right ventricle. ANP levels were obtained in 24 patients and BNP levels were obtained in 22 patients with systemic right ventricle. Patients underwent exercise study (n = 22) and cardiovascular magnetic resonance imaging (n = 11) or equilibrium radionuclide angiography (n = 13) to determine RVEF. There were 17 patients with complete transposition and 7 patients with corrected transposition. ANP showed an inverse correlation with RVEF (r2 = 0.63, p < 0.001), a weak but statistically significant inverse correlation with exercise duration (r2 = 0.18, p = 0.047) and no relationship with maximal oxygen consumption (peak V'O2) (r2 = 0.10, p = NS). BNP did not show a relationship with any of the parameters measured. ANP shows a strong inverse correlation with RVEF and a weak correlation with exercise duration in patients with a systemic right ventricle. BNP does not show a significant relationship when compared with either parameter. ANP might be a useful tool for identification of systolic right ventricular dysfunction.

Continuous positive airway pressure improves exercise capacity and heart rate recovery in obstructive sleep apnea

BACKGROUND

There is a relationship between obstructive sleep apnea (OSA) and heart failure (HF). Peak oxygen consumption (peak VO(2)), heart rate recovery, and N-terminal-pro-BNP (NT-proBNP) are strong prognostic predictors in HF. The effects of nasal continuous positive airway pressure (nCPAP) on these parameters in OSA patients are not well defined.

METHODS

Forty patients with newly diagnosed OSA [apnea-hypopnea index (AHI) 37 (20-65) h(-1)] underwent cardiopulmonary exercise testing for assessment of peak VO(2) and heart rate recovery at one (HRR-1) and two (HRR-2) minutes after exercise termination as well as NT-proBNP measurement at baseline and after 7.9+/-1.4 months of effective nCPAP (nightly usage>3.5 h). The effects of nCPAP were compared in patients with mild-to-moderate (AHI<30 h(-1); n=16) vs. severe (AHI>or=30 h(-1); n=24) OSA.

RESULTS

In the group as a whole, peak VO(2) (baseline: 31.9+/-9.3 vs. follow-up: 33.7+/-9.0 ml/kg/min; p=0.02) and HRR-2 [38 (32-43) vs. 42 (32-47) bpm; p=0.01] but not HRR-1 [22 (15-26) vs. 22 (16-27) bpm; p=0.16] improved from baseline to follow-up. The effect on peak VO(2) was mainly driven by a trend towards an increase in patients with mild-to-moderate OSA (31.8+/-10.7 vs. 33.9+/-10.2 ml/kg/min; p=0.08), whereas an effect on HRR-1 [20 (15-23) vs. 21 (16-26) bpm; p=0.03] and HRR-2 [38 (29-42) vs. 42 (33-47) bpm; p=0.004] was observed only in those with severe OSA. NT-proBNP levels remained unchanged [21 (11-45) vs. 26 (5-52) pg/ml; p=0.6].

CONCLUSIONS

Treatment with nCPAP is associated with an improvement in peak VO(2) and heart rate recovery in patients with OSA.

Association of increased arterial stiffness and inflammation with proteinuria and left ventricular hypertrophy in non-diabetic hypertensive patients

OBJECTIVE

Both arterial stiffness and proteinuria are important markers for organ damage in hypertension. This study was planed to investigate the association between arterial stiffness and inflammation and to define the influences of proteinuria on arterial stiffness and inflammation in non-diabetic hypertension.

METHODS

We enrolled 205 patients (mean age 41 +/- 8 years, 66 women) with essential hypertension noted for less than 5 years in this study. They did not have diabetes mellitus or any overt cardiac, vascular, or renal complications. Stiffness index (SI) derived from digital volume pulse was used for assessment of arterial stiffness. High-sensitivity C-reactive protein (hsCRP) was measured in each patient during enrollment. Left ventricular hypertrophy (LVH) was documented by electrocardiography and proteinuria was assessed by measuring 24-h urine protein.

RESULTS

SI was significantly correlated with hsCRP (r = 0.166, p = 0.017). LVH was noted in 34 patients (17%). SI was significantly higher in patients with LVH (8.03 +/- 1.74 vs 7.19 +/- 1.19 m/s, p = 0.001). Proteinuria was noted in three patients with LVH. SI was gradually increased among patients without LVH, with LVH but not proteinuria, and with LVH and proteinuria (7.19 +/- 1.19, 7.68 +/- 1.21, 11.75 +/- 2.51 m/s respectively; p<0.001). HsCRP was also gradually increased among patients without LVH, with LVH but not proteinuria, and with LVH and proteinuria (0.20 +/- 0.24, 0.30 +/- 0.59, 1.56 +/- 1.58 mg/dl respectively; p<0.001).

CONCLUSIONS

SI was significantly correlated with hsCRP. Arterial stiffness and inflammation were increased in association with proteinuria in non-diabetic essential hypertension.

NT-proBNP and the diagnosis of left ventricular systolic dysfunction within two acute NHS trust catchment areas: the initial Teesside experience

PURPOSE

To evaluate the predictive value of N-terminal pro B-type natiuretic peptide (NT-proBNP) reference cut-off values as diagnostic markers for left ventricular systolic dysfunction (LVSD).

STUDY DESIGN

A retrospective study assessing the use of NT-proBNP in the diagnostic algorithm for the investigation of patients with suspected signs and symptoms of LVSD presenting to primary care.

RESULTS

A generic NT-proBNP cut-off (150 ng/l) value has similar negative and positive predictive valves, specificity and sensitivity compared to age and sex specific cut-off values.

CONCLUSION

When using NT-proBNP as a triage tool for screening patients with signs and symptoms suggestive of LVSD, a simple generic cut-off level is as effective as more complex age sex specific cut-off values.

N-terminal pro-B-type natriuretic peptide and functional capacity in patients with obstructive sleep apnea

The obstructive sleep apnea syndrome (OSAS) is associated with cardiovascular abnormalities including left ventricular hypertrophy, left ventricular diastolic dysfunction, and endothelial dysfunction. The present study evaluated whether N-terminal pro-B-type natriuretic peptide (NT-proBNP) and peak oxygen consumption (peak VO(2)), both integral markers of cardiovascular function, are related to OSAS severity. In addition, we tested whether NT-proBNP levels depend on body composition in OSAS patients, similar to what has been reported in patients without OSAS. Eighty-nine patients with untreated OSAS underwent NT-proBNP measurement, dual X-ray absorptiometry, and cardiopulmonary exercise testing. In a representative subgroup (n = 32), transthoracic echocardiography was performed. The severity of OSAS was classified based on apnea-hypopnea index (AHI) values as mild (AHI 5-15 h(-1)), moderate (AHI 15-30 h(-1)), and severe (AHI >30 h(-1)). OSAS was mild in 19 (21%), moderate in 21 (24%), and severe in 49 (55%) patients. NT-proBNP levels did not differ among patients with mild [30 (10-57)], moderate [37 (14-55)], and severe [24 (13-49) pg/ml; p = 0.8] OSAS and were not related to body mass index (r = 0.07; p = 0.5), percent lean body mass (r = -0.17; p = 0.1), and percent fat mass (r = 0.18; p = 0.1). Percent predicted peak VO(2) was on average normal and did not differ among patients with mild (115 +/- 26), moderate (112 +/- 23), and severe OSAS (106 +/- 29%; p = 0.4). Body weight-indexed peak VO(2) did not differ among patients with mild (31.9 +/- 10.3), moderate (32.1 +/- 7.9), and severe OSAS (30.0 +/- 9.9 ml kg(-1) min(-1); p = 0.6) either. Lower NT-proBNP (beta = -0.2; p = 0.02) was independently but weakly associated with higher body weight-indexed peak VO(2). In the echocardiography subgroup, NT-proBNP was not significantly related to left ventricular mass index (r = 0.26; p = 0.2). In conclusion, NT-proBNP and peak VO(2) are not related to OSAS severity, and NT-proBNP poorly reflects left ventricular hypertrophy in OSAS. The lack of a relationship between NT-proBNP and OSAS severity is not due to a significant influence of body composition on NT-proBNP. There is an association between higher NT-proBNP and lower peak VO(2), indicating that NT-proBNP is a marker of cardiorespiratory fitness in patients with OSAS. However, the association is too weak to be clinically useful.

Plasma N terminal pro-brain natriuretic peptide levels and its determinants in a multi-ethnic population

This study documents the determinants and plasma levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) among hypertensive and normotensive subjects in a multi-ethnic population in the United Arab Emirates (UAE). We obtained demographic, anthropometric and clinical data, together with fasting NT-proBNP and biochemical indices from 128 hypertensive patients and 138 normotensive subjects matched for age, gender and ethnicity. Plasma NT-proBNP levels were significantly (P<0.001), and several-fold higher among hypertensives (median 5.92, inter quartile range (IQR): 1.79-18.48 pmol/l) than normotensives (median 1.78, IQR: 0.59-4.32 pmol/l) in the total study population, and the same was true for the ethnic groups separately. Similarly, plasma levels of glucose, blood urea nitrogen (BUN) and creatinine, but not insulin, were significantly (P<0.05) higher among hypertensives than normotensives. For all subjects combined, log NT-proBNP correlated positively and significantly with age (P<0.01), log glucose (P<0.05), systolic blood pressure (SBP, P<0.001), log BUN (P<0.001) and log creatinine (P<0.001). Multivariate regression analysis showed that NT-proBNP levels were independently and positively correlated with SBP, age, gender, log BUN, Emirati and South East Asian ethnic groups and inversely associated with current exercise. In conclusion, we found circulating levels of NT-proBNP to be significantly increased in hypertensive versus normotensive subjects in the UAE and independently related to SBP, age, gender, indices of renal function and possibly exercise. Our results further suggest a possible modulating effect of ethnicity on NT-proBNP levels.

Left ventricular hypertrophy, subclinical atherosclerosis, and inflammation

To elucidate mechanisms by which left ventricular (LV) hypertrophy (LVH) increases the risk of atherosclerotic heart disease, we sought to determine whether LVH is independently associated with coronary artery calcium (CAC) and serum C-reactive protein (CRP) levels in the general population. The Dallas Heart Study is a population-based sample in which 2633 individuals underwent cardiac MRI to measure LV structure, electron beam CT to measure CAC, and measurement of plasma CRP. We used univariate and multivariable analyses to determine whether LV mass and markers of concentric LV hypertrophy or dilation were associated with CAC and CRP. Increasing quartiles of LV mass indexed to fat-free mass, LV wall thickness, and concentricity, but not LV volume, were associated with CAC in both men and women (P<0.001). After adjustment for traditional cardiovascular risk factors and statin use, LV wall thickness and concentricity remained associated with CAC in linear regression (P<0.001 for each). These associations were particularly robust in blacks. LV wall thickness and concentricity were also associated with elevated CRP levels (P=0.001 for both) in gender-stratified univariate analyses, although these associations did not persist in multivariable analysis. In conclusion, concentric LVH is an independent risk factor for subclinical atherosclerosis. LVH is also associated with an inflammatory state as reflected in elevated CRP levels, although this relationship appears to be mediated by comorbid conditions. These data likely explain in part why individuals with LVH are at increased risk for myocardial infarction.

Interpretation of B-type natriuretic peptide in cardiac disease and other comorbid conditions

B-Type natriuretic peptide (BNP) is elevated in states of increased ventricular wall stress. BNP is most commonly used to rule out congestive heart failure (CHF) in dyspneic patients. BNP levels are influenced by age, gender and, to a surprisingly large extent, by body mass index (BMI). In addition, it can be elevated in a wide variety of clinical settings with or without CHF. BNP is elevated in other cardiac disease states such as the acute coronary syndromes, diastolic dysfunction, atrial fibrillation (AF), amyloidosis, restrictive cardiomyopathy (RCM), and valvular heart disease. BNP is elevated in non-cardiac diseases such as pulmonary hypertension, chronic obstructive pulmonary disease, pulmonary embolism, and renal failure. BNP is also elevated in the setting of critical illness such as in acute decompensated CHF (ADHF) and sepsis. This variation across clinical settings has significant implications given the increasing frequency with which BNP testing is being performed. It is important for clinicians to understand how to appropriately interpret BNP in light of the comorbidities of individual patients to maximize its clinical utility. We will review the molecular biology and physiology of natriuretic peptides as well as the relevant literature on the utilization of BNP in CHF as well as in other important clinical situations, conditions that are commonly associated with CHF and or dyspnea.

Use of Plasma B-Type Natriuretic Peptide Level to Identify Asymptomatic Hypertensive Patients with Abnormal Diurnal Blood Pressure Variation Profiles: Nondippers, Extreme Dippers, and Risers

We examined the relationship between plasma B-type natriuretic peptide (BNP) level and diurnal variability pattern of blood pressure (BP). Twenty-four-hour ambulatory BP monitoring was performed in 98 patients with asymptomatic essential hypertension, and the patients were classified into four groups according to their circadian BP variation profiles: dippers (n=29), nondippers (n=36), extreme dippers (n=19), and risers (n=14). Plasma BNP was measured by enzyme immunoassay. Based on the distribution pattern of BNP values, the values were analyzed after logarithmic transformation. Significant differences in plasma BNP levels among the types of circadian BP variations were demonstrated by analysis of variance (p<0.0005). Nondippers and risers showed significantly higher plasma BNP levels (mean [range: -1 SD and +1 SD]: 16.1 [6.3, 41.6] pg/mL and 29.2 [15.9, 53.4] pg/mL, respectively) than dippers (8.4 [3.7, 19.1] pg/mL). The area under the receiver operating characteristics curve for distinguishing patients with abnormal circadian BP variation from those with normal variation was 0.72, indicating that plasma BNP levels were useful for distinguishing between these patients. Specificity of 69% and sensitivity of 72% were obtained with a cut-off value of 10.5 pg/mL (log plasma BNP, 1.02) for distinguishing the abnormal diurnal BP profile group from the normal group. In conclusion, hypertensive patients with abnormal diurnal BP variation patterns (nondippers, extreme dippers, and risers) showed higher plasma BNP levels than those with normal circadian BP variation (dippers). Plasma BNP level is clinically useful for the identification of hypertensive patients who have abnormal circadian BP variability, which increases the risk of cardiovascular events.

C-reactive protein and echocardiography have little impact on risk stratification in never-treated hypertensive patients

The aim of this study was to assess the contribution of increased concentrations of high-sensitivity C-reactive protein (hsCRP) and echocardiography to risk stratification according to the 2003 European guidelines for the management of arterial hypertension in patients with untreated hypertension. A total of 207 consecutive medical outpatients with untreated hypertension were included. History and clinical examination, electrocardiography, laboratory analyses including the measurement of hsCRP and echocardiography were performed in all patients. Patients were classified into four risk groups with and without using echocardiography and hsCRP concentrations of at least 10 mg/l according to the 2003 guidelines for the management of hypertension. The majority of the 207 patients (81%) were at moderate or high cardiovascular risk before adding echocardiography and/or hsCRP to the risk stratification process. When echocardiography was included, only three patients were reclassified from the moderate added risk to the high added risk group. Adding hsCRP concentrations of at least 10 mg/l had no impact on risk stratification. Using an hsCRP cutoff level of 3 mg/l, one patient was at moderate instead of low added risk, eight patients were at high instead of moderate added risk and one patient was at very high instead of high added risk. We conclude that hsCRP at the proposed cutoff level of 10 mg/l has no impact on risk stratification in outpatients with untreated hypertension. An hsCRP cutoff level of 3 mg/l may be more suitable for risk stratification. Finally, our data suggest that depending on the population studied, there is minimal impact of echocardiography on risk stratification.