Is cardiovascular remodeling in patients with essential hypertension related to more than high blood pressure? A LIFE substudy. Losartan Intervention For Endpoint-Reduction in Hypertension

Multimodality cardiovascular imaging in hypertension

PURPOSE OF THE REVIEW

Hypertension accounts for the largest proportion of cardiovascular (CV) mortality worldwide and its prevalence continues to rise. While prominent CV societies have offered strong recommendations on the management of hypertension in adults, the role of noninvasive CV imaging in the evaluation of hypertensive patients remains incompletely defined.

RECENT FINDINGS

Noninvasive imaging is a rapidly expanding field with a growing number of sophisticated and readily applicable modalities to assess how cardiac structure and function changes after periods of sustained, elevated blood pressure. Echocardiography remains the initial modality to screen these patients while developments in nuclear, computed tomography and cardiac magnetic resonance complement and expand investigations for alternative diagnoses that may complement or conflict with the diagnosis of left ventricular hypertrophy.

SUMMARY

In this review article, we summarize the application of echocardiography, nuclear imaging, cardiac computed tomography, and cardiac magnetic resonance imaging in the evaluation and management of hypertensive heart disease.

Multimodality Imaging in Sarcomeric Hypertrophic Cardiomyopathy: Get It Right…on Time

Hypertrophic cardiomyopathy (HCM) follows highly variable paradigms and disease-specific patterns of progression towards heart failure, arrhythmias and sudden cardiac death. Therefore, a generalized standard approach, shared with other cardiomyopathies, can be misleading in this setting. A multimodality imaging approach facilitates differential diagnosis of phenocopies and improves clinical and therapeutic management of the disease. However, only a profound knowledge of the progression patterns, including clinical features and imaging data, enables an appropriate use of all these resources in clinical practice. Combinations of various imaging tools and novel techniques of artificial intelligence have a potentially relevant role in diagnosis, clinical management and definition of prognosis. Nonetheless, several barriers persist such as unclear appropriate timing of imaging or universal standardization of measures and normal reference limits. This review provides an overview of the current knowledge on multimodality imaging and potentialities of novel tools, including artificial intelligence, in the management of patients with sarcomeric HCM, highlighting the importance of specific "red alerts" to understand the phenotype-genotype linkage.

Left ventricular hypertrophy and hypertension

Hypertension (HTN) is a major modifiable risk factor for cardiovascular disease (CVD) morbidity and mortality. The left ventricle (LV) is a primary target for HTN end-organ damage. In addition to being a marker of HTN, LV geometrical changes: concentric remodeling, concentric or eccentric LV hypertrophy (LVH) are major independent risk factors for not only CVD morbidity and mortality but also for all-cause mortality and neurological pathologies. Blood pressure control with lifestyle changes and antihypertensive agents has been demonstrated to prevent and regress LVH. Herein, we provide a comprehensive review of literature on the relationship between HTN and LV geometry abnormalities with a focus on diagnosis, prognosis, pathophysiological mechanisms, and treatment approaches.

Impact of left ventricular concentricity on long-term mortality in a hospital-based population in Japan

Background

The prognostic impact of relative wall thickness (RWT), ventricular concentricity, is controversial.

Methods

We retrospectively analyzed data obtained from 4444 consecutive patients who had undergone both transthoracic echocardiography and electrocardiography at our hospital in 2013. Those who presented with a history of previous episodes of myocardial infarctions and severe or moderate valvular disease were excluded from the analysis. We calculated RWT as follows: (2 x diastolic posterior wall thickness) / (the diastolic LV dimension). We defined high RWT as a ratio > 0.42. A total of 3654 patients were categorized into two groups: 492 with high RWT, and 3162 with normal RWT.

Results

The mean ages of those in the normal and high RWT groups were 64.6 (±standard deviation 16.3) and 71.6 (± 12.7) years, respectively (p<0.001). Prevalence of male sex, history of diabetes, hypertension, and chronic kidney disease, and the left atrium volume index was higher for the high RWT group than for the normal RWT group. The median follow-up period was 1274 days (interquartile range, 410–1470). The Kaplan-Meier curves showed a constant increase in all-cause death, with cumulative 3-year incidences of 18.3% and 10.8% for the high RWT and normal RWT groups, respectively (log-rank p<0.001). After adjusting for confounders, the increased mortality risk for those with high RWT relative to normal RWT was significant (hazard ratio, 1.64; 95% confidence interval, 1.27–2.10). This trend was consistent for the composite of deaths and major adverse cardiac events.

Conclusion

High RWT has a deleterious impact on long-term mortality.

The emerging role of Cardiovascular Magnetic Resonance in the evaluation of hypertensive heart disease

BACKGROUND

Arterial hypertension is the commonest cause of cardiovascular death. It may lead to hypertensive heart disease (HHD), including heart failure (HF), ischemic heart disease (IHD) and left ventricular hypertrophy (LVH).

MAIN BODY

According to the 2007 ESH/ESC guidelines, the recommended imaging technique is echocardiography (echo), when a more sensitive detection of LVH than that provided by ECG, is needed. Cardiovascular Magnetic Resonance (CMR), a non-invasive, non-radiating technique, offers the following advantages, beyond echo: a) more reliable and reproducible measurements of cardiac parameters such as volumes, ejection fraction and cardiac mass b) more accurate differentiation of LVH etiology by providing information about tissue characterisation c) more accurate evaluation of myocardial ischemia, specifically if small vessels disease is present d) technique of choice for diagnosis of renovascular, aortic tree/branches lesions and quantification of aortic valve regurgitation e) technique of choice for treatment evaluation in clinical trials. The superiority of CMR against echocardiography in terms of reproducibility, operator independency, unrestricted field of view and capability of tissue characterization makes the technique ideal for evaluation of heart, quantification of aortic valve regurgitation, aorta and aortic branches.

CONCLUSIONS

CMR has a great potential in early diagnosis, risk stratification and treatment follow up of HHD. However, an international consensus about CMR in HHD, taking under consideration the cost-benefit ratio, expertise and availability, is still warranted.

Utility of magnetic resonance imaging in the evaluation of left ventricular thickening

Left ventricular (LV) thickening can be due to hypertrophy (concentric, asymmetric, eccentric) or remodelling (concentric or asymmetric). Pathological thickening may be caused by pressure overload, volume overload, infiltrative disorders, hypertrophic cardiomyopathy, athlete's heart or neoplastic infiltration. Magnetic resonance imaging (MRI) plays an important role in the comprehensive evaluation of LV thickening, including: establishing diagnosis, determining LV geometry, establishing aetiology, quantification, identifying prognostic factors, serial follow-up and treatment response. In this article, we review the aetiologies and pathophysiology of LV thickening, and demonstrate the comprehensive role of MRI in the evaluation of LV thickening.

TEACHING POINTS

• MRI plays an important role in the evaluation of LV thickening. • LV thickening can be due to either hypertrophy or remodelling. • Pathological thickening can be due to pressure/volume overload or infiltrative disorders.

Carotid artery thickening and neurocirculatory abnormalities in de novo Parkinson disease

Cognitive dysfunction constitutes a major non-motor manifestation of Parkinson disease (PD), but the mechanisms remain incompletely understood. Neurocirculatory abnormalities such as supine hypertension (SH) and orthostatic hypotension (OH), white matter hyperintensities upon magnetic resonance imaging, and dementia are inter-related in PD, even in patients with early, levodopa-untreated disease. These abnormalities might in turn be associated with carotid atherosclerosis which, by a variety of interacting means could contribute to repeated episodes of cerebral hypo- and hyper-perfusion. We investigated inter-correlations among neurocirculatory and carotid sonographic measurements [intimal-medial thickness (IMT) and wall:lumen ratios (WLR)] in 65 patients with levodopa-untreated, de novo PD who underwent tilt table testing and 24-h ambulatory blood pressure monitoring. Increased mean IMT and WLR were associated with OH and supine and overnight blood pressures. Across individuals the orthostatic fall in systolic pressure was correlated with both IMT and WLR. Since arteriosclerosis would be expected to splint carotid sinus baroreceptors, complex positive interactions among carotid wall thickening, SH, and OH may result in myriad episodes of cerebral hypo- and hyper-perfusion, contributing to microvascular injury and consequently to the cognitive dysfunction attending PD.

Auto-amplification of cortisol actions in human carotid atheroma is linked to arterial remodeling and stroke

High cortisol and aldosterone levels increase cardiovascular risk, but the respective roles of each hormone within the arterial wall remain controversial. We tested the hypothesis that cortisol production within the arterial wall may contribute to atherosclerotic remodeling and act through illicit activation of the mineralocorticoid receptor (MR). Gene expression studies of the corticoid system components and marker genes of the atherosclerotic process in human carotid atheroma plaque and nearby macroscopically intact tissue (MIT) were considered together with clinical data and compared with pharmacological stimulations of human vascular smooth muscle cells (VSMCs) in contractile or lipid-storing phenotypes. The components of corticoid production and action were present and active within the human carotid wall and VSMCs. Atheroma plaque and lipid-storing VSMCs expressed 11β-hydroxysteroid deshydrogenase-1 (11β-HSD1) at two- to tenfold higher levels than MIT or contractile VSMCs. The 11β-HSD1 expression was stimulated by cortisol and cortisone, especially in lipid-storing VSMCs. MR mRNA level was lower in atheroma and lipid-storing VSMCs and downregulated via MR by fludrocortisone and cortisol. Cortisol upregulated collagen1 and MCP-1 mRNAs via the glucocorticoid receptor (GRα), in both VSMC phenotypes, whereas fludrocortisone stimulated the collagen1 expression only in lipid-storing VSMCs. The GRα mRNA level in MIT was higher in patients with previous stroke and correlated positively with the collagen1 mRNA but negatively with diastolic blood pressure. Local cortisol production by 11β-HSD1, and its action via high parietal GRα could be relevant from the first step of atherosclerotic remodeling and auto-amplify with transdifferentiation of VSMCs during atheroma progression.

Cardiovascular magnetic resonance in systemic hypertension

Systemic hypertension is a highly prevalent potentially modifiable cardiovascular risk factor. Imaging plays an important role in the diagnosis of underlying causes for hypertension, in assessing cardiovascular complications of hypertension, and in understanding the pathophysiology of the disease process. Cardiovascular magnetic resonance (CMR) provides accurate and reproducible measures of ventricular volumes, mass, function and haemodynamics as well as uniquely allowing tissue characterization of diffuse and focal fibrosis. In addition, CMR is well suited for exclusion of common secondary causes for hypertension. We review the current and emerging clinical and research applications of CMR in hypertension.

Relationship between arterial impedance and concentric remodeling in patients with normal systolic function: impact on prevalence and survival

Although concentric remodeling (CR) is associated with increased morbidity and mortality, little is known regarding the interaction of arterial impedance (IMP) on survival in CR. The authors evaluated 50,421 patients with normal systolic function to assess prevalence of CR and impact of CR and IMP on survival (mean follow-up, 3.9±2.3 years.) In 2636 patients with paired echocardiograms, the authors assessed the impact of IMP on mortality, based on maintaining a high or low IMP (> or <4.0 mm Hg/mL/m(2) ). CR occurred in 21% of patients and was associated with twice the mortality compared with patients with normal left ventricular (LV) structure (P<.0001). The prevalence of CR increased with increasing IMP (P<.001 for trend). In the paired cohort, CR patients with an IMP <4.0 had a mortality of 6.3%, with 58% converting to normal LV structure, whereas mortality was higher (10%; P<.0001) and conversion to normal LV structure was less frequent (46%; P<.001) in those whose IMP remained ≥4.0. CR is prevalent and associated with high mortality and increases with higher IMP. Reducing IMP levels in CR is associated with lower mortality and greater conversion to normal LV structure. Studies are needed to determine whether reporting and targeting IMP is beneficial in CR.

Biomarkers of left ventricular hypertrophy and remodeling in blacks

Left ventricular (LV) hypertrophy, a marker for adverse cardiovascular events, is more common in blacks than in non-Hispanic whites. Mechanisms leading to LV hypertrophy and mediating its clinical sequelae in blacks are not fully understood. We investigated the associations of 39 candidate biomarkers in distinct biological pathways with LV mass and geometry in blacks. Participants included 1193 blacks (63±9 years of age; 72% women; 78% hypertensive) belonging to hypertensive sibships. LV mass was measured by transthoracic echocardiography and indexed to height.(2.7) LV geometry was categorized as normal, concentric remodeling, concentric hypertrophy, and eccentric hypertrophy. Generalized estimating equations were used to assess associations of the 39 biomarkers with LV mass index after adjustment for age, sex, and conventional risk factors. After adjustment for potential confounders, log-transformed levels of the following biomarkers were independently associated with LV mass index: N-terminal pro-brain natriuretic peptide (β±SE=0.07±0.01 pg/mL; P<0.0001), mid-regional pro-atrial natriuretic peptide (β±SE=0.08±0.02 pmol/L; P<0.0001), mid-regional pro-adrenomedullin (β±SE=0.09±0.03 nmol/L; P=0.0006), C-terminal pro-endothelin (β± SE=0.05±0.02 pmol/L; P=0.0009), and osteoprotegerin (β±SE=0.07±0.02 pg/mL; P=0.0005) (β is for 1 log increase in biomarker level). The associations of these biomarkers with LV mass index were mainly due to their association with eccentric hypertrophy. Higher circulating levels of natriuretic peptides, adrenomedullin, endothelin, and osteoprotegerin were associated with increased LV mass index, providing insights into the pathophysiology of LV hypertrophy in blacks.

Association of left ventricular hypertrophy with incident hypertension: the multi-ethnic study of atherosclerosis

Increased left ventricular (LV) mass and changes in LV geometry may precede hypertension onset. The authors examined the associations of LV mass and geometry, assessed by cardiac magnetic resonance imaging, with hypertension incidence in 2,567 normotensive participants enrolled in 2000-2002 in the Multi-Ethnic Study of Atherosclerosis, an ethnically diverse, population-based, US study. Over a median follow-up of 4.8 years, 745 (29%) participants developed hypertension. In a fully adjusted model including baseline blood pressure, the relative risks of incident hypertension from the lowest to highest LV mass quartile were 1.00 (referent), 1.13 (95% confidence interval (CI): 0.89, 1.43), 1.28 (95% CI: 1.00, 1.63), and 1.78 (95% CI: 1.38, 2.30) (P < 0.001 for linear trend). Higher levels of LV concentric geometry, defined by higher LV mass to end-diastolic volume quartiles, were associated with higher risk of incident hypertension in a fully adjusted model (P = 0.044 for linear trend). In a final model containing both quartiles of LV mass and LV mass/volume along with all covariates including baseline blood pressure, higher LV mass quartiles were associated with incident hypertension (P < 0.001 for linear trend), whereas higher LV mass/volume quartiles were not (P = 0.643 for linear trend). In this multiethnic cohort, alterations in LV mass preceded hypertension onset among normotensive individuals.

Alterations in capillary morphology are found in mild blood pressure elevation

OBJECTIVES

Remodeling of small resistance arteries is an early sign of target organ damage in hypertension. Peripheral capillary morphology abnormalities in hypertension are not well studied. The study objective was to determine whether altered capillary morphology is associated with SBP, DBP, or both in individuals without and with mild blood pressure elevation (SBP = 130-160 mmHg). Another objective was to determine whether capillary morphology is associated with minimum forearm vascular resistance, a measure of altered resistance artery structure.

METHODS

Participants included 115 nonpregnant, nondiabetic individuals 23-55 years of age. A five-component morphology score (distribution, tone, configuration, hypertrophy, and extravasates) was developed to describe fingernail bed capillaries visualized using venous congestion in digital photomicrographs. Multiple linear regression models adjusted for age, sex, race, tobacco use, hyperglycemia, dyslipidemia, and renal function were used to analyze the relationship between SBP, DBP, and minimum forearm vascular resistance with the morphology score.

RESULTS

The total morphology score was significantly associated with SBP and DBP as well as minimum forearm vascular resistance (P < 0.005 for all). Among the five individual morphology score components, hypertrophy was significantly associated with SBP and DBP (P = 0.002 and 0.001, respectively), whereas extravasates were significantly associated with SBP only (P = 0.002).

CONCLUSION

A five-component capillary morphology score is associated with SBP, DBP, and altered resistance artery structure in individuals with and without mild blood pressure elevation. These observations suggest that target organ damage at the level of the microcirculation can be detected using capillary morphology.

Association between transforming growth factor-beta(1) and left ventricular mass and diameter in hypertensive patients

Angiotensin II influences development of left ventricular hypertrophy (LVH) by stimulating cardiomyocyte hypertrophy, fibroblast proliferation, and collagen synthesis. Because pro-fibrotic actions of angiotensin may be mediated by increased production of transforming growth factor-beta(1) (TGF-beta(1)), we assessed whether serum TGF-beta(1) levels might reflect involvement in LVH development. We analyzed relationships between left ventricular mass and levels of renin, aldosterone, and TGF-beta(1) in 67 hypertensive subjects (mean age 64 +/- 11.3 years) with electrocardiographic evidence of LVH. Levels were obtained after a 2-week washout of antihypertensive medications; two-dimensional echocardiography was subsequently performed. Linear regression analysis showed a correlation between TGF-beta(1) and LV mass (r = 0.36, P = .002). This was apparently explained by the correlation between TGF-beta(1) and left ventricular diastolic internal diameter (r = 0.42, P < .001), because no correlation between TGF-beta(1) levels and LV wall thickness was found. In multivariate analysis, the correlation between TGF-beta(1) and internal diameter remained significant (r = 0.39, P = .0014). There were no racial differences in levels of TGF-beta(1) or left ventricular geometry, and no correlations between age, blood pressure, renin, aldosterone, and left ventricular mass or dimensions. These findings indicate that serum TGF-beta(1) levels are related to left ventricular structure in hypertensive subjects, suggesting its possible involvement in the process of hypertensive left ventricular remodeling.

Clinical impact of left ventricular hypertrophy and implications for regression

Left ventricular hypertrophy (LVH) is an independent risk factor and predictor of cardiovascular (CV) events and all-cause mortality. Patients with LVH are at increased risk for stroke, congestive heart failure, coronary heart disease, and sudden cardiac death. Left ventricular hypertrophy represents both a manifestation of the effects of hypertension and other CV risk factors over time as well as an intrinsic condition causing pathologic changes in the CV structure and function. We review the risk factors for LVH and its consequences, concentric remodeling, and its prognostic significance, clinical benefits and supporting evidence for LVH regression, and its implications for management. We conclude our review summarizing the various pharmacological and nonpharmacological therapeutic options approved for the treatment of hypertension and LVH regression and the supporting clinical trial data for these therapeutic strategies.

Spectrum of M-mode echocardiographic abnormalities in 75 cats with systemic hypertension

A retrospective study was performed in 75 hypertensive cats to determine the spectrum and frequency of M-mode echocardiographic abnormalities. Results indicated that 21.3% of the cats had M-mode measurements within normal reference ranges. For cats with echocardiographic abnormalities, changes were variable. Thirty-nine percent of hypertensive cats had hypertrophy of the interventricular septum in diastole, and 41.3% had hypertrophy of the left ventricular (LV) posterior wall in diastole. One cat in five had a dilated left atrium, while fractional shortening and LV internal dimension in diastole were normal in 82.7% and 86.7% of the cats, respectively. The marked variability of echocardiographic findings in hypertensive cats made echocardiography an unreliable screening test for hypertension.

Irbesartan reduces common carotid artery intima-media thickness in hypertensive patients when compared with atenolol: the Swedish Irbesartan Left Ventricular Hypertrophy Investigation versus Atenolol (SILVHIA) study

BACKGROUND AND PURPOSE

Angiotensin II promotes cell growth and has been implicated in the development and maintenance of left ventricular (LV) hypertrophy and of structural vascular changes. We wished to examine whether an angiotensin receptor blocker (ARB) would influence structural vascular changes beyond the effects of blood pressure reduction.

METHODS

Hypertensive patients with LV hypertrophy (age 55 +/- 9 years, blood pressure 162 +/- 19/104 +/- 8 mmHg, LV mass index 148 +/- 31 g m(-2); mean +/- SD) were randomized double-blind to the ARB irbesartan (n=52) or the beta(1) receptor blocker atenolol (n=56) for 48 weeks. Ultrasonography of the left and right common carotid artery (CCA) and echocardiography were performed at week 0 and 48.

RESULTS

With similar reductions in blood pressure, CCA intima-media thickness (IMT) was reduced by irbesartan (from 0.92 +/- 0.14 by 0.01 +/- 0.10 mm, NS), whereas it was increased by atenolol (from 0.94 +/- 0.21 by 0.03 +/- 0.12 mm, P=0.018; P=0.002 between groups). CCA lumen diameter was less reduced by irbesartan than by atenolol. Thus, CCA intima-media area was reduced by irbesartan (from 21.3 +/- 5.0 by 0.90 +/- 2.45 mm(2), P=0.034) but not by atenolol (from 21.3 +/- 6.1 by 0.18 +/- 2.71 mm(2), NS; P=0.037 between groups). Changes in CCA IMT or area did not relate to changes in LV mass.

CONCLUSIONS

The favourable effects by irbesartan on CCA IMT with an outward vascular remodelling suggest that angiotensin II mediates structural vascular changes, beyond the effects of blood pressure. This may be important in the prevention of cerebrovascular events.

Altered gene expression pattern in peripheral blood leukocytes from patients with arterial hypertension

The role of various inflammatory mechanisms and oxidative stress in the development of atherosclerosis and arterial hypertension (AH) has been increasingly acknowledged during recent years. Hypertension per se or factors that cause hypertension along with other complications lead to infiltration of activated leukocytes in the vascular wall, where these cells contribute to the development of vascular injury by releasing cytokines, oxygen radicals, and other toxic mediators. However, molecular mechanisms underlying leukocyte activation at transcriptional level in AH are still far from being clear. To solve this problem we employed cDNA microarray technology to reveal the differences in gene expression in peripheral blood leukocytes from patients with AH compared with healthy individuals. The microarray data were verified by a semi-quantitative RT-PCR method. We found 25 genes with differential expression in leukocytes from AH patients among which 21 genes were upregulated and 4 genes were downregulated. These genes are implicated in apoptosis (CASP2, CASP4, and CASP8, p53, UBID4, NAT1, and Fte-1), inflammatory response (CAGC, CXCR4, and CX3CR1), control of MAP kinase function (PYST1, PAC1, RAF1, and RAFB1), vesicular trafficking of molecules among cellular organelles (GDI-1 and GDI-2), cell redox homeostasis (GLRX), cellular stress (HSPA8 and HSP40), and other processes. Gene expression pattern of the majority of genes was similar in AH patients independent of the disease stage and used hypotensive therapy, but was clearly different from that of normotensive subjects.

Left ventricular geometry and mortality in patients >70 years of age with normal ejection fraction

Numerous studies have indicated that left ventricular (LV) hypertrophy predicts morbidity and mortality, including studies in older patients. The prognostic impact of other LV geometric patterns, including concentric remodeling (CR), compared with LV hypertrophy has not been studied in a large cohort of older patients. Echocardiographic and clinical data were studied in 9,771 consecutive patients aged >70 years with ejection fractions > or =50% who were followed for 3.1 years to determine the impact of LV geometric patterns. CR was the most prevalent pattern (43%), and 16% met criteria for LV hypertrophy. Although patients with CR had significantly lower LV mass indexes than patients with normal structure as well as those with LV hypertrophy, their mortality was 35% higher than that of normal subjects (15.5% vs 11.5%, p <0.0001) and 13% higher than that of patients with eccentric LV hypertrophy (15.5% vs 13.7%, p <0.001) with similar mortality to those with concentric LV hypertrophy (15.5% vs 15.9%). In conclusion, abnormal LV geometry is extremely common in patients aged >70 years with normal systolic function, being present in 59% of this population, with CR (43%) by far the most common LV geometric pattern. Patients aged >70 years with CR have significantly increased mortality compared with similarly aged patients with either normal structure or eccentric LV hypertrophy, with similar increased mortality to those with concentric LV hypertrophy.

Arterial plasma noradrenaline predicts left ventricular mass independently of blood pressure and body build in men who develop hypertension over 20 years

BACKGROUND

Increased sympathetic activity may be an underlying mechanism in cardiovascular disease. It has been hypothesized that the degree of left ventricular (LV) hypertrophy is partly related to the blood pressure level, and partly to neurohormonal factors. The aim of this study was to investigate predictors of LV mass, including arterial plasma noradrenaline as an index of sympathetic activity, with particular emphasis on subjects who developed hypertension over a period of 20 years.

METHODS

In a 20-year prospective study of middle-aged men, sustained hypertensives (n = 22), new hypertensives (crossovers) (n = 17) and sustained normotensives (controls) (n = 17) were examined both at baseline and after 20 years of follow-up (at ages 42.1 +/- 0.5 and 62.3 +/- 0.6 years, respectively). Relationships between arterial plasma catecholamines, blood pressure and body mass index at baseline to left ventricular parameters by echocardiography at follow-up were investigated.

RESULTS

Groups were homogeneous regarding age, gender, race and body build. The group of sustained hypertensives had significantly more LV hypertrophy (P = 0.025) and diastolic dysfunction (P = 0.010). Among the crossovers, LV mass index was positively correlated to arterial plasma noradrenaline (r = 0.50, P = 0.043) and body mass index (BMI) (r = 0.51, P = 0.039) and showed a positive trend with systolic blood pressure (SBP) at baseline. Arterial plasma noradrenaline (beta = 0.47) was found to predict LV mass index after 20 years independently of BMI (beta = 0.45) and SBP (beta = 0.22) at baseline (R adjusted = 0.345, P = 0.037). Such a relationship was not found in the controls or in the sustained hypertensives, of which 16 were treated with antihypertensive drugs.

CONCLUSIONS

Arterial plasma noradrenaline at baseline, as an index of sympathetic activity, predicts LV mass at follow-up independently of systolic blood pressure and body build in middle-aged men who developed hypertension over a period of 20 years.

Soluble guanylate cyclase stimulation on cardiovascular remodeling in angiotensin II-induced hypertensive rats

It is unknown whether long-term pharmacological stimulation of soluble guanylate cyclase (sGC), elevating intracellular cGMP levels, has a beneficial effect on hypertension. The purpose of this study is to investigate the effects of BAY41-2272, an orally available sGC stimulator, on cardiovascular remodeling in hypertensive rats. Eight-week-old male Wistar rats with hypertension induced by angiotensin II infused subcutaneously at 250 ng/kg per minute were treated orally with a low ([L] 2 mg/kg per day) or high ([H] 10 mg/kg per day) dose of BAY41-2272 for 14 days. BAY41-2272-H partially suppressed the rise in blood pressure and reduced the heart weight (4.20+/-0.34 versus 3.68+/-0.20 mg/g; P<0.01), whereas BAY41-2272-L had no effect. However, both doses decreased the angiotensin II-induced left ventricular accumulation of collagen in the perivascular area (L, -20%, P<0.05; H, -30%, P<0.01) and myocardial interstitium (L, -21%, P<0.05; H, -38%, P<0.01), reducing the number of activated fibroblasts surrounding coronary arteries (L, -74%; H, -79%; P<0.05). BAY41-2272 downregulated the angiotensin II-induced left ventricular gene expression of type 1 collagen (L, -41%, P<0.05; H, -49%, P<0.01) and transforming growth factor-beta1 (L, -49%, P<0.05; H, -65%, P<0.01). cGMP levels were elevated by BAY41-2272 not only in the left ventricle, but also in cultured cardiac fibroblasts, resulting in reduced thymidine incorporation into the cells. Thus, stimulation of sGC by BAY41-2272 attenuates fibrosis of the left ventricle in rats with angiotensin II-induced hypertension partly in a pressure-independent manner, suggesting an important role for sGC generating cGMP in inhibiting cardiovascular remodeling.

Left ventricular hypertrophy and arterial wall thickening in children with essential hypertension

OBJECTIVE

Our aim was to determine the prevalence of left ventricular hypertrophy (LVH) and increased intima-media thickness (IMT) in Caucasian children with newly diagnosed, untreated essential hypertension (EH).

PARTICIPANTS

Our study cohort consisted of 72 children with EH (mean age: 14.5 years; range: 5-18 years). The control groups consisted of 103 age-matched, healthy children.

METHODS

We evaluated the left ventricular mass (LVM), intima-media thickness in the carotid (cIMT) and superficial femoral (fIMT) arteries, 24-h ambulatory blood pressure, and biochemical cardiovascular risk factors.

RESULTS

Of the hypertensive children examined, 41.6% had LVM above the 95th percentile, and 13.2% had LVM above 51 g/m2.7. Of the hypertensive subjects, the cIMT was above 2 SDS of normal values in 38.8%, and the flMT was above 2 SDS of normal values in 17.5%. Patients with LVM above 51 g/m2.7 had a higher birth weight than other patients. LVM, cIMT, and fIMT correlated with 24-h SBP and pulse pressure; LVM also correlated with homocysteine and serum uric acid concentrations. fIMT correlated with low Aprotein A1 (ApoA1), higher ApoB and C reactive protein, and daily sodium excretion. Step-wise regression analysis revealed that serum uric acid and higher birth weight were predictors for LVM, pulse pressure was a predictor for cIMT, and ApoB was a predictor for fIMT.

CONCLUSIONS

A significant number of adolescents with EH already had cardiovascular damage at diagnosis. LVM and markers of arterial injury correlate with SBP, biochemical, and perinatal cardiovascular risk factors. Serum uric acid and higher birth weight are predictors of LVM.

Reductions in albuminuria and in electrocardiographic left ventricular hypertrophy independently improve prognosis in hypertension: the LIFE study

BACKGROUND

In the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study, reduced urine albumin/creatinine ratio (UACR) as well as regression of left ventricular hypertrophy have been associated with lower incidence of cardiovascular events. We wanted to investigate whether these prognostic improvements were independent.

METHODS

In 6679 hypertensive patients included in the LIFE study, we measured UACR, left ventricular hypertrophy by electrocardiography, serum cholesterol, plasma glucose and blood pressure after 2 weeks of placebo treatment and again after 1 year of anti-hypertensive treatment with either an atenolol- or a losartan-based regimen. During this first year of treatment, 77 patients encountered a non-fatal stroke or myocardial infarction and were excluded to avoid bias. During the next 3-4 years, 610 composite endpoints [cardiovascular death (n = 228), fatal or non-fatal myocardial infarction or stroke] were recorded.

RESULTS

In Cox regression analyses, the composite endpoint was after adjustment for treatment allocation predicted by baseline logUACR [hazard ratio (HR) = 1.16 per 10-fold increase, P < 0.05], 1-year logUACR (HR = 1.29 per 10-fold increase), baseline Sokolow-Lyon voltage (HR = 1.01 per mm, both P < 0.001) and 1-year Cornell product (HR = 1.01 per 100 mm x ms, P < 0.01). Cardiovascular death was predicted by 1-year logUACR (HR = 1.59, P < 0.001), baseline Sokolow-Lyon voltage (HR = 1.01, P = 0.06) and 1-year Cornell product (HR = 1.02, P < 0.001). Both were predicted independent of age, Framingham risk score, current smoking, history of cardiovascular disease and diabetes. Gender, serum cholesterol, plasma glucose and blood pressure did not enter the models.

CONCLUSIONS

Baseline UACR and Sokolow-Lyon voltage, as well as in-treatment UACR and Cornell product, added to the risk prediction independent of traditional risk factors, indicating that albuminuria and left ventricular hypertrophy reflect different aspects of cardiovascular damage and are modifiable cardiovascular risk factors.

Left ventricular geometry and survival in patients with normal left ventricular ejection fraction

In hypertensive populations, left ventricular (LV) geometry, which is characterized by hypertrophy, predicts cardiovascular outcome. The left ventricle can also alter its shape by concentric remodeling (CR) in the absence of LV hypertrophy, a feature that is detected by echocardiography. This study assessed the prevalence and prognostic significance of various forms of LV geometry and changes in LV geometry over time in patients with normal LV systolic function. Retrospective analysis of a large clinical population (n = 35,602) that was referred for echocardiography was done, with all-cause mortality as the primary outcome. Abnormal LV geometry was identified in 46% of patients, with CR present in 35% (n = 12,362) and LV hypertrophy in 11% (n = 3,958). Patients with abnormal LV geometry were older and more obese compared with subjects with normal LV geometry. There was a strong relation between abnormal LV geometry and mortality, and patients with CR and LV hypertrophy exhibited considerably higher relative risk for all-cause mortality compared with subjects with normal LV geometry (relative risk [RR] 1.99, 95% confidence interval [CI] 1.88 to 2.18, p <0.0001; RR 2.13, 95% CI 1.89 to 2.40, p <0.0001, respectively). Subjects with CR who reverted to a normal geometric pattern had improved survival (RR 0.64, 95% CI 0.42 to 0.97, p = 0.03) compared with those who progressed to LV hypertrophy (RR 1.54, 95% CI 1.01 to 2.47, p = 0.05). In conclusion, CR, a form of cardiac adaptation, is frequently noted in patients with normal LV ejection fractions and confers a risk of death similar to that of LV hypertrophy. Normalization of CR is associated with better survival, whereas transition to LV hypertrophy increases mortality.

The cardiovascular continuum and renin-angiotensin-aldosterone system blockade

A progressive chain of pathophysiological events links cardiovascular risk factors to clinical manifestations of disease and life-threatening cardiovascular events. This chain--the cardiovascular continuum--underlies cardiovascular disease and holds the key to its prevention and treatment. Progressive tissue damage can result in morbidity from congestive heart failure, end-stage heart disease, nephrotic proteinuria and dementia and, eventually, death from cardio- or cerebrovascular causes. The renin-angiotensin-aldosterone system (RAAS) is involved at all stages of the cardiovascular continuum, because the effector molecules of the RAAS, angiotensin II in particular, have direct pathobiological effects on a variety of tissues, including the endothelium, vascular smooth muscle and the renal mesangium. Clinical trials of angiotensin II receptor blockers (ARBs) and angiotensin-converting enzyme (ACE) inhibitors have demonstrated the essential validity of this hypothesis. Interruption of the RAAS has been shown to reduce cardiovascular morbidity and mortality in patients with left ventricular hypertrophy, heart failure and post-myocardial infarction, as well as renal disease in patients with type 2 diabetes. Key questions remain, however. What are the clinical effects of combination ARB and ACE inhibitor treatment? How will combinations of RAAS blockade with other agents, such as statins, affect the cardiovascular continuum? Answers to these questions will require well-planned, adequately powered clinical trials, such as the Programme of Research tO evaluate Telmisartan End-organ proteCTION (PROTECTION) and the ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET) programmes. However, it is already clear that RAAS blockade is an essential part of blocking progression along the cardiovascular continuum.

Nurse-recorded clinic and ambulatory blood pressures correlate equally well with left ventricular mass and carotid intima-media thickness

OBJECTIVE

To assess relationships between noninvasive ambulatory blood pressure (BP), clinic BP (mean value of three readings in the seated position measured by nurses), structural cardiac indices, intima-media thickness of the common carotid artery and several hormones.

DESIGN

Cross-sectional study of 75 subjects with hypertension and left ventricular hypertrophy (HTH) according to echocardiography, 35 subjects with hypertension and normal left ventricular dimensions (HT) and 23 normotensive subjects (NT).

RESULTS

We found an excellent correlation between mean 24-h ambulatory BP and clinic BP, the r-value for systolic BP being 0.82 and for diastolic levels 0.78 (both P < 0.0001). Clinic and ambulatory BP correlated equally well with left ventricular (LV) mass index (r-values between 0.55 and 0.64, all P < 0.0001) and to intima-media thickness of the carotid artery (r = 0.18-0.34, P < 0.01). The systolic white-coat effect (clinic BP - day-time BP) was higher in the HTH and HT compared with NT and was weakly correlated to LV mass index (r = 0.18, P = 0.04). Nondippers (mean arterial night/day BP ratio of > 0.9) had higher brain (6.1 +/- 7.5 pmol L(-1) vs. 3.7 +/- 3.2 pmol L(-1), P = 0.01) and atrial (14 +/- 3.4 pmol L(-1) vs. 9.3 +/- 5.4 pmol L(-1), P = 0.04) natriuretic peptide levels, and also exhibited a lower ejection fraction (49 +/- 8% vs. 57 +/- 9%, P = 0.006), than dippers.

CONCLUSION

Clinic BP recordings performed by nurses as three measurements 1 min apart provide excellent relationship to target organ damage. Nondippers exhibited signs of a more advanced hypertensive organ damage than dippers which corresponds well with the poor prognosis linked to this condition.

Improving outcomes in the post-myocardial infarction setting

Heart disease is the leading cause of death in the United States, with African-American men having the highest rate of cardiovascular mortality in the US population. Although the clustering of multiple cardiovascular risk factors is particularly apparent in this group, a key reason for the higher rate of cardiovascular mortality among African-American men compared with other ethnic groups may be related to underdiagnosis and undertreatment. Studies have shown that minority persons with myocardial infarction are less likely than non-minorities to be diagnosed, to receive appropriate drug therapy, or to undergo bypass surgery. However, there are no data that suggest established treatments and secondary prevention strategies are less effective in African Americans. Appropriate therapy for secondary prevention--including thrombolysis, antiplatelet strategies, angiotensin-converting enzyme inhibition, beta blockade, and lipid-lowering therapies--results in significant reductions in mortality for all patients.

Albuminuria predicts cardiovascular events independently of left ventricular mass in hypertension: a LIFE substudy

We wanted to investigate whether urine albumin/creatinine ratio (UACR) and left ventricular (LV) mass, both being associated with diabetes and increased blood pressure, predicted cardiovascular events in patients with hypertension independently. After 2 weeks of placebo treatment, clinical, laboratory and echocardiographic variables were assessed in 960 hypertensive patients from the LIFE Echo substudy with electrocardiographic LV hypertrophy. Morning urine albumin and creatinine were measured to calculate UACR. The patients were followed for 60+/-4 months and the composite end point (CEP) of cardiovascular (CV) death, nonfatal stroke or nonfatal myocardial infarction was recorded. The incidence of CEP increased with increasing LV mass (below the lower quartile of 194 g to above the upper quartile of 263 g) in patients with UACR below (6.7, 5.0, 9.1%) and above the median value of 1.406 mg/mmol (9.7, 17.0, 19.0%(***)). Also the incidence of CV death increased with LV mass in patients with UACR below (0, 1.4, 1.3%) and above 1.406 mg/mmol (2.2, 6.4, 8.0%(**)). The incidence of CEP was predicted by logUACR (hazard ratio (HR)=1.44(**) for every 10-fold increase in UACR) after adjustment for Framingham risk score (HR=1.05(***)), history of peripheral vascular disease (HR=2.3(*)) and cerebrovascular disease (HR=2.1(*)). LV mass did not enter the model. LogUACR predicted CV death (HR=2.4(**)) independently of LV mass (HR=1.01(*) per gram) after adjustment for Framingham risk score (HR=1.05(*)), history of diabetes mellitus (HR=2.4(*)) and cerebrovascular disease (HR=3.2(*)). (*)P<0.05, (**)P<0.01, (***)P<0.001. In conclusion, UACR predicted CEP and CV death independently of LV mass. CV death was predicted by UACR and LV mass in an additive manner after adjustment for Framingham risk score and history of CV disease.

Is inappropriate left ventricular mass related to neurohormonal factors and/or arterial changes in hypertension? a LIFE substudy

We investigated whether inappropriately high left ventricular (LV) mass, defined as observed LV mass exceeding the level of individual LV mass predicted from gender, height, and stroke work, may be associated with an imbalance between growth-promoting and growth-inhibitory factors and/or structural vascular changes. In 53 patients with hypertension and electrocardiographic LV hypertrophy, 24-h ambulatory blood pressure (BP); echocardiographic LV mass, stroke volume and stroke work; minimal forearm vascular resistance (MFVR); and intima-media cross-sectional area in common carotid arteries (IMA) were evaluated after 2 weeks of placebo treatment. Serum insulin, plasma epinephrine, norepinephrine, endothelin, angiotensin II, aldosterone, and brain natriuretic peptide (BNP) were also measured. High observed LV mass was related to high IMA (r=0.46, P<0.001), MFVR (in men: r=0.36, P<0.05), 24-h ambulatory systolic BP (r=0.30, P=0.06), and lower plasma angiotensin II (r=-0.33, P<0.05), but not to other circulating growth factors. Stroke work was similarly related to IMA (r=0.42, P<0.01), MFVR (in men: r=0.41, P<0.05), and plasma angiotensin II (r=-0.32, P<0.05). Inappropriate LV mass, identified by the ratio between observed LV mass and the value predicted for gender, height, and stroke work, was not significantly related to any of the arterial or neurohormonal variables. In this small series of older hypertensive patients, inappropriate LV mass was not significantly related to arterial changes or to measured circulating growth factors, although weak relations cannot be excluded. Alternatively, inappropriately high LV mass might be related to unmeasured factors such as local myocardial alterations in growth factors and/or genetic predisposition to develop excessive LV hypertrophy.

[Hypertensive heart disease and microangiopathy]

Cardiac alterations in patients with arterial hypertension comprise the manifestation of stenosis in epicardial arteries, disease of coronary resistive vessels, prothrombotic changes and endothelial dysfunction, pronounced perivascular and interstitial fibrosis, left ventricular hypertrophy, dilatation of the left atrium, increased sympathetic drive and degeneration of aortic valve. These alterations leads to the major clinical manifestations of hypertensive heart disease, that are symptoms of reduced coronary conductance, left ventricular hypertrophy, diastolic and systolic dysfunction with or without left ventricular enlargement and arrhythmia. Different non-invasive and invase procedures are available for screening and follow up of patients with hypertensive heart disease. The primary therapeutic target is, apart from lowering blood pressure, to reverse cardiac manifestations of arterial hypertension using specific therapeutic algorithms.

Clinical implications of carotid artery remodeling in acute coronary syndrome

OBJECTIVES

We investigated the relationship between ultrasonographic features of the carotid artery and the angiographic features of coronary plaques in acute coronary syndrome (ACS).

BACKGROUND

The carotid intima-media thickness (IMT) may be a marker of advanced coronary artery disease.

METHODS

Consecutive ACS patients (N = 125) underwent B-mode ultrasonography within one week of the acute coronary event. Using a 7.5-MHz linear array transducer, the common carotid IMT, interadventitial diameter, and luminal diameter were examined. Carotid plaques were also assessed. Then patients were divided into two groups based on the number of complex plaques identified by coronary angiography.

RESULTS

The carotid IMT of 75 patients with multiple complex coronary plaques was significantly larger than that of 50 patients with solitary plaques (p < 0.0003). The prevalence of soft and hard carotid plaques was higher in the group with multiple coronary plaques than in those with single plaques (28% vs. 12%, p < 0.04 and 13% vs. 0%, p < 0.008, respectively). Additionally, the carotid interadventitial diameter was larger in the patients with multiple plaques than in those with single plaques (7.93 +/- 0.97 mm vs. 7.48 +/- 0.88 mm, p < 0.01), and a significant correlation was observed between the carotid IMT and interadventitial diameter (R = 0.54, p < 0.0001).

CONCLUSIONS

In ACS, multiple complex coronary plaques are associated with positive carotid remodeling, suggesting that plaque vulnerability may be a systemic phenomenon.

Management of the hypertensive patient with coronary insufficiency but without atherosclerosis

Arterial hypertension is a major risk factor for the clinical syndrome of angina pectoris, in which the ECG is abnormal but the coronary arteries are normal. Structural and functional abnormalities in coronary circulation as well as extravascular factors (eg, left-ventricular hypertrophy, fibrosis with diastolic dysfunction) compromise the adequate ratio of coronary blood flow to oxygen demand causing angina, dyspnea, and major cardiac events. Recent studies stress the importance to functional disturbances of coronary microvasculature leading to profound morphologic changes associated with impaired coronary conductance. In patients without epicardial coronary stenosis hypertensive microvascular disease can be qualitatively assessed by noninvasive diagnostic approaches based on new Doppler echocardiography techniques and may also be monitored by widely available stress tests. For ultimate quantitative assessment, invasive procedures are still required. Beyond guidelines to control blood pressure in hypertensive individuals, restoration of functional and structural integrity of the coronary microvasculature represents the ultimate therapeutic goal in hypertensive patients with coronary insufficiency and without angiographic evidence of atherosclerosis. Concomitant factors reducing coronary conductance such as left-ventricular hypertrophy and diastolic dysfunction should be reversed in parallel. Currently, therapeutic intervention in the renin-aldosterone-angiotensin-II-system using ACE inhibitors, angiotensin receptor blockers, and low doses of aldosterone antagonists represent the most promising strategy to achieve these goals. Using the knowledge of these recent results we should refine the overall management of our hypertensive patients with coronary insufficiency but without atherosclerosis.

Are left ventricular mass, geometry and function related to vascular changes and/or insulin resistance in long-standing hypertension? ICARUS: a LIFE substudy

Vascular hypertrophy and insulin resistance have been associated with abnormal left ventricular (LV) geometry in population studies. We wanted to investigate the influence of vascular hypertrophy and insulin resistance on LV hypertrophy and its function in patients with hypertension. In 89 patients with essential hypertension and electrocardiographic LV hypertrophy, we measured blood pressure; insulin sensitivity by hyperinsulinaemic euglucaemic clamp; minimal forearm vascular resistance (MFVR) by plethysmography; intima-media cross-sectional area of the common carotid arteries (IMA) by ultrasound; and LV mass, relative wall thickness (RWT), systolic function and diastolic filling by echocardiography after two weeks of placebo treatment. LV mass index correlated to IMA/height (r=0.36, P=0.001), serum insulin (r=-0.25, P<0.05), plasma glucose (r=-0.34, P<0.01), and showed a tendency towards a correlation to insulin sensitivity (r=0.21, P=0.051), but was unrelated to MFVR. Deceleration time of early diastolic transmitral flow positively correlated to IMA/height (r=0.30, P<0.01). The ratio between early and atrial LV filling peak flow velocity negatively correlated to MFVR(men) (r=-0.30, P<0.05). Endocardial and midwall systolic LV function were not related to vascular hypertrophy, plasma glucose, serum insulin or insulin sensitivity. In conclusion, insulin resistance was not related to LV hypertrophy or reduced LV function. However, high thickness of the common carotid arteries was associated with LV hypertrophy and high deceleration time of early diastolic transmitral flow. High MFVR was associated with low ratio between early and atrial LV filling peak flow velocity. This may suggest that systemic vascular hypertrophy contributes to abnormal diastolic LV relaxation in patients with hypertension and electrocardiographic LV hypertrophy.