Concentric or Eccentric Hypertrophy: How Clinically Relevant Is the Difference?

AI-based cluster analysis enables outcomes prediction among patients with increased LVM

Background

The traditional classification of left ventricular hypertrophy (LVH), which relies on left ventricular geometry, fails to correlate with outcomes among patients with increased LV mass (LVM).

Objectives

To identify unique clinical phenotypes of increased LVM patients using unsupervised cluster analysis, and to explore their association with clinical outcomes.

Methods

Among the UK Biobank participants, increased LVM was defined as LVM index ≥72 g/m2 for men, and LVM index ≥55 g/m2 for women. Baseline demographic, clinical, and laboratory data were collected from the database. Using Ward's minimum variance method, patients were clustered based on 27 variables. The primary outcome was a composite of all-cause mortality with heart failure (HF) admissions, ventricular arrhythmia, and atrial fibrillation (AF). Cox proportional hazard model and Kaplan-Meier survival analysis were applied.

Results

Increased LVM was found in 4,255 individuals, with an average age of 64 ± 7 years. Of these patients, 2,447 (58%) were women. Through cluster analysis, four distinct subgroups were identified. Over a median follow-up period of 5 years (IQR: 4-6), 100 patients (2%) died, 118 (2.8%) were admissioned due to HF, 29 (0.7%) were admissioned due to VA, and 208 (5%) were admissioned due to AF. Univariate Cox analysis demonstrated significantly elevated risks of major events for patients in the 2nd (HR = 1.6; 95% CI 1.2-2.16; p < .001), 3rd (HR = 2.04; 95% CI 1.49-2.78; p < .001), and 4th (HR = 2.64; 95% CI 1.92-3.62; p < .001) clusters compared to the 1st cluster. Further exploration of each cluster revealed unique clinical phenotypes: Cluster 2 comprised mostly overweight women with a high prevalence of chronic lung disease; Cluster 3 consisted mostly of men with a heightened burden of comorbidities; and Cluster 4, mostly men, exhibited the most abnormal cardiac measures.

Conclusions

Unsupervised cluster analysis identified four outcomes-correlated clusters among patients with increased LVM. This phenotypic classification holds promise in offering valuable insights regarding clinical course and outcomes of patients with increased LVM.

Echocardiographic Differences in Women Across Subtypes of Hypertensive Disorders of Pregnancy

Background

Hypertensive disorders of pregnancy (HDP) can be classified into gestational hypertension, preeclampsia (PRE), and chronic hypertension with superimposed preeclampsia (SPE).

Objectives

The purpose of this study was to retrospectively examine the echocardiographic differences in biventricular structure and function in 3 HDP groups of women in comparison to normotensive pregnant controls.

Methods

Women with an echocardiogram during or within the first year of pregnancy were identified within our integrated health network. Exclusion criteria included age <18 years, diagnosis of pulmonary embolism, malignancy, autoimmune disease, and structural heart disease.

Results

We identified a total of 706 subjects (cases: n = 427, normotensive controls: n = 279). Cases were divided into 3 groups: gestational hypertension (n = 57), PRE (n = 291), and SPE (n = 79). In adjusted analyses, echocardiographic parameters demonstrated a graded difference in left ventricular (LV) mass index, relative wall thickness, mitral inflow E, mitral inflow A, septal e', lateral e', E/e', left atrial volume index, tricuspid velocity, and lateral e' velocities with the most profound findings noted in the SPE group. Specifically, adjusted LV mass index (adjusted β = 14.45, 95% CI: 9.00-19.90) and E/e' (adjusted β = 2.97, 95% CI: 2.27-3.68) was highest in the SPE group in comparison to controls (P < 0.001).

Conclusions

LV remodeling and diastolic filling abnormalities are more common in HDP and are most evident in SPE and PRE. Echocardiography during or immediately after pregnancy may be useful in these high-risk women to identify these abnormalities. The long-term implications of these echocardiographic abnormalities require further study.

Timing of Surgery for Asymptomatic Primary Mitral Regurgitation: Possible Value of Early, Serial Measurements of Left Ventricular Sphericity

Asymptomatic primary mitral regurgitation due to myxomatous degeneration of the mitral valve leaflets may remain so for long periods, even as left ventricular function progresses to a decompensated stage. During the early compensated stage, the ventricle's initial response to the volume overload is an asymmetric increase in the diastolic short axis dimension, accomplished by a diastolic shift of the interventricular septum into the right ventricular cavity, creating a more spherical left ventricular diastolic shape, increasing diastolic filling and stroke volume. Early valve repair is recommended to reduce postoperative left ventricular dysfunction. Early serial measurements of left ventricular sphericity index [LV-Si]. during the compensated stage of mitral regurgitation might identify subtle changes in left ventricular shape and assist in determining the optimal earliest timing for surgical intervention.

Blood pressure in heart failure management and prevention

Hypertension is a leading cause of heart failure and other cardiovascular diseases. Its role in the pathogenesis of heart failure with reduced ejection fraction (HFrEF) differs from that in heart failure with preserved ejection fraction (HFpEF). Moreover, rigorous blood pressure control may reduce the incidence of heart failure. However, once heart failure develops, prognosis is affected by blood pressure, which may differ between patients with and without heart failure. Therefore, the association between guideline-directed medical therapy (GDMT) for heart failure and its uptitration must be considered for blood pressure management and should not be overlooked. Heart failure medications affect the blood pressure and efficacy per baseline blood pressure value. This review discusses the potential mechanisms by which hypertension leads to HFrEF or HFpEF, the impact of hypertension on incident heart failure, and the recommended approaches for blood pressure management in patients with heart failure. Comparison between patients with and without heart failure regarding blood pressure The association between CV events and SBP is linear in patients without heart failure; however, it becomes J-shaped or inverse linear in those with heart failure. The management of BP, including optimal BP or pharmacotherapy, differs between the two populations. ACEi angiotensin-converting enzyme inhibitors, ARB angiotensin II receptor blockers; ARNi angiotensin receptor-neprilysin inhibitors, BB beta-blockers, BP blood pressure, CV cardiovascular, DASH Dietary Approaches to Stop Hypertension, GDMT guideline-directed medical therapy, HF heart failure, HFrEF heart failure with reduced ejection fraction, MRA mineralocorticoid receptor antagonists, SBP systolic blood pressure, SGLT2i sodium-glucose cotransporter 2 inhibitors.

Relationship between vascular ageing and left ventricular geometry in patients with newly diagnosed primary aldosteronism

BACKGROUND

Changes in left ventricular (LV) geometry are early manifestations of cardiac damage. The relationship between vascular aging and LV geometry has been reported. However, in newly diagnosed primary aldosteronism (PA), with more severe target organ damage than essential hypertension, the relationship between vascular aging and LV geometry has never been described.

METHODS

We conducted a retrospective study among newly diagnosed PA from 1 January 2017 to 30 September 2021 at the Third Xiangya Hospital. The data of vascular aging parameters were collected, including ankle-brachial index (ABI), brachial-ankle pulse wave velocity (baPWV), and carotid intima-media thickness (cIMT). Echocardiography data were collected to assess LV geometry patterns.

RESULTS

A total of 146 patients with newly diagnosed PA were included. The mean age was 44.77 ± 9.79 years, and 46.58% participants were women. Linear regression analysis adjusting all potential confounders showed that cIMT was significantly associated with LV mass index (LVMI) (β=0.164, P=0.028) and baPWV was significantly associated with relative wall thickness (RWT) (β= 0.00005, P=0.025). Multifactorial adjusted logistic regression analysis demonstrated that cIMT was significantly associated with LV hypertrophy (LVH) (OR=7.421, 95%CI: 1.717-815.688, P=0.021) and baPWV was significantly associated with LV concentric geometry (LVCG) (OR=1.003, 95%CI: 1.001-1.006, P=0.017).

CONCLUSION

baPWV was significantly associated with LVCG and cIMT was significantly associated with LVH in newly diagnosed PA. This study provides insights on the importance of baPWV measurement and cIMT measurement in early assessment of cardiac damage in newly diagnosed PA.

Inorganic nitrate attenuates cardiac dysfunction: role for xanthine oxidoreductase and nitric oxide

Nitric oxide (NO) is a vasodilator and independent modulator of cardiac remodelling. Commonly, in cardiac disease (e.g. heart failure) endothelial dysfunction (synonymous with NO-deficiency) has been implicated in increased blood pressure (BP), cardiac hypertrophy and fibrosis. Currently no effective therapies replacing NO have succeeded in the clinic. Inorganic nitrate (NO₃ ^- ), through chemical reduction to nitrite and then NO, exerts potent BP-lowering but whether it might be useful in treating undesirable cardiac remodelling is unknown. In a nested age- and sex-matched case-control study of hypertensive patients +/- left ventricular hypertrophy (NCT03088514) we show that lower plasma nitrite concentration and vascular dysfunction accompany cardiac hypertrophy and fibrosis in patients. In mouse models of cardiac remodelling, we also show that restoration of circulating nitrite levels using dietary nitrate improves endothelial dysfunction through targeting of xanthine oxidoreductase (XOR)-driven H₂ O₂ and superoxide, and reduces cardiac fibrosis through NO-mediated block of SMAD-phosphorylation leading to improvements in cardiac structure and function. We show that via these mechanisms dietary nitrate offers easily translatable therapeutic options for treatment of cardiac dysfunction.

Echocardiographic left ventricular geometry profiles for prediction of stroke, coronary heart disease and all-cause mortality in the Chinese community: a rural cohort population study

Background

The utility of echocardiographic left ventricular (LV) geometry in the prediction of stroke/coronary heart disease (CHD) and all-cause mortality is not well characterized. This study aimed to evaluate the overall and sex-specific prognostic value of different geometric patterns on the incidence of stroke/CHD and all-cause mortality in a Chinese population-based cohort.

Methods

We conducted a prospective study in the general population in Northeast China, and a total of 9940 participants aged ≥ 35 years underwent echocardiography for LV geometry and were successfully followed up for incident stroke/CHD and all-cause death. Cox proportional hazards models were utilized to estimate the association of baseline LV geometry with adverse outcomes.

Results

Over a median follow-up of 4.66 years, abnormal LV geometric patterns had increased crude incident rates of stroke/CHD and all-cause mortality compared with normal geometry in overall population and each sex group (all P < 0.05). Multivariable Cox analysis reported that LV concentric and eccentric hypertrophy were associated with incident stroke/CHD (concentric hypertrophy: hazard ratio (HR) = 1.39, 95% confidence interval (CI) = 1.04–1.86; eccentric hypertrophy: HR = 1.42, 95% CI = 1.11–1.82) and all-cause mortality (concentric hypertrophy: HR = 1.50, 95% CI = 1.07–2.12; eccentric hypertrophy: HR = 1.58, 95% CI = 1.19–2.10), and LV concentric remodeling was related to stroke/CHD incidence (HR = 1.42, 95% CI = 1.09–1.84) in total population compared to normal geometry after the adjustment for potential confounders. In men, a significant increase was observed from LV eccentric hypertrophy for incident stroke/CHD, whereas in women, LV concentric hypertrophy was associated with elevated incidence of both stroke/CHD and all-cause death, and eccentric hypertrophy was correlated with increased all-cause mortality (all P < 0.05).

Conclusions

Our prospective cohort supports that abnormal LV geometry by echocardiography has a prognostic significance for incident stroke/CHD and all-cause mortality, implying that early detection and intervention of LV structural remodeling in rural China are urgently needed to prevent adverse outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02055-w.

A thermodynamic transient cross-bridge model for prediction of contractility and remodelling of the ventricle

Cardiac hypertrophy is an adaption of the heart to a change in cardiovascular loading conditions. The current understanding is that progression may be stress or strain driven, but the multi-scale nature of the cellular remodelling processes have yet to be uncovered. In this study, we develop a model of the contractile left ventricle, with the active cell tension described by a thermodynamically motivated cross-bridge cycling model. Simulation of the transient recruitment of myosin results in correct patterns of ventricular pressure predicted over a cardiac cycle. We investigate how changes in tissue loading and associated deviations in transient force generation can drive restructuring of cellular myofibrils in the heart wall. Our thermodynamic framework predicts in-series sarcomere addition (eccentric remodelling) in response to volume overload, and sarcomere addition in parallel (concentric remodelling) in response to valve and signalling disfunction. This framework provides a significant advance in the current understanding of the fundamental sub-sarcomere level biomechanisms underlying cardiac remodelling. Simulations reveal that pathological tissue loading conditions can significantly alter actin-myosin cross-bridge cycling over the course of the cardiac cycle. The resultant variation in sarcomere stress pushes an imbalance between the internal free energy of the myofibril and that of unbound contractile proteins, initiating remodelling. The link between cross-bridge thermodynamics and myofibril remodelling proposed in this study may significantly advance current understanding of cardiac disease onset.

Relationship Between Vascular Aging and Left Ventricular Concentric Geometry in Community-Dwelling Elderly: The Northern Shanghai Study

Purpose

There have been few recent studies regarding vascular aging and its relationship with left ventricular (LV) geometry. Moreover, the association of abnormal LV geometry with various kinds of vascular aging has not yet been systematically analyzed. Thus, this study aimed to further elucidate this relationship.

Materials and Methods

In this study, 3363 older participants (43.6% male, aged 71.1±5.9 years; 56.4% female, aged 71.1±6.1 years) derived from the Northern Shanghai Study were enrolled. Vascular aging criteria included arteriosclerosis, defined as carotid-femoral pulse wave velocity >10 m/s or brachial-ankle pulse wave velocity >1800 cm/s, and peripheral atherosclerosis, defined as ankle-brachial index <0.9, carotid artery intima-media thickness (cIMT) greater than 0.9 mm, or carotid plaque indicating carotid artery abnormality. Micro-albuminuria was defined as urinary albumin-to-creatinine ratio >30 mg/g. Decreased estimated glomerular filtration rate (eGFR) was defined as eGFR <60 mL/min/1.73 m².

Results

When vascular aging parameters were respectively adjusted for age and sex, arteriosclerosis, micro-albuminuria, and peripheral atherosclerosis were significantly associated with concentric remodeling, eccentric LV hypertrophy (LVH), and concentric LVH (P<0.045) but not with decreased eGFR or abnormal cIMT and presence of plaque. Peripheral atherosclerosis was strongly associated with LV concentric geometry (LVCG) when considering other covariates (risk factors, diseases, and treatments) (P<0.012).

Conclusion

Vascular aging parameters such as arteriosclerosis, micro-albuminuria, and peripheral atherosclerosis are significantly and independently associated with LVCG in community-dwelling older Chinese population, suggesting the importance of vascular aging during early clinical assessment of abnormal LV geometry change and serious cardiovascular events.

Heart Plasticity in Response to Pressure- and Volume-Overload: A Review of Findings in Compensated and Decompensated Phenotypes

The adult human heart has an exceptional ability to alter its phenotype to adapt to changes in environmental demand. This response involves metabolic, mechanical, electrical, and structural alterations, and is known as cardiac plasticity. Understanding the drivers of cardiac plasticity is essential for development of therapeutic agents. This is particularly important in contemporary cardiology, which uses treatments with peripheral effects (e.g., on kidneys, adrenal glands). This review focuses on the effects of different hemodynamic loads on myocardial phenotype. We examine mechanical scenarios of pressure- and volume overload, from the initial insult, to compensated, and ultimately decompensated stage. We discuss how different hemodynamic conditions occur and are underlined by distinct phenotypic and molecular changes. We complete the review by exploring how current basic cardiac research should leverage available cardiac models to study mechanical load in its different presentations.

Platycodin D Reverses Pathological Cardiac Hypertrophy and Fibrosis in Spontaneously Hypertensive Rats

Platycodin D (PD) is the main active saponin isolated from Platycodon grandiflorum (PG) and is reported to exhibit anticancer, anti-angiogenic, anti-inflammation and anti-obesity biological effects. The current study aims to evaluate the therapeutic efficacy of PD in cardiac fibrosis and for hypertrophy in spontaneous hypertension rats (SHRs) and to verify inhibition of the signaling pathway. Significant increases in the cardiac functional indices of left ventricular internal diameter end diastole (LVIDd) and left ventricular internal diameter end systole (LVIDs); the eccentric hypertrophy marker p-MEK5; concentric hypertrophy markers, such as CaMKII[Formula: see text] and calcineurin; and expression levels of NFATc3, p-GATA4 and BNP were observed in spontaneously hypertensive groups. PD treatment reversed these increases in SHRs. In addition, an increase in the fibrosis markers FGF2, uPA, MMP2, MMP9, TGF[Formula: see text]-1 and CTGF during cardiac hypertrophy was detected by western blotting analyses. These results demonstrated that PD treatment considerably attenuates cardiac fibrosis. Histopathological examination revealed that PD treatment remarkably reduced collagen accumulation in contrast to spontaneously hypertensive groups. This study clearly suggests that PD provides myocardial protection by alleviating two damaging responses to hypertension, fibrosis and hypertrophy, in the heart.

Left ventricular geometry in obesity: Is it what we expect?

Obesity is characterized by the disproportionate growth of the components of body size, including adipose tissue and lean body mass. Left ventricular (LV) hypertrophy often develops, due to the coexistence of hemodynamic (cardiac workload) and non-hemodynamic components (including body composition and activity of visceral fat). While the hypertrophy of cardiomyocytes is produced by the hemodynamic load, through sarcomeric replication, there is a parallel growth of non-muscular myocardial components, including interstitial fat infiltration and accumulation of triglycerides in the contractile elements, which are thought to influence LV geometric pattern. Thus, pure intervention on hemodynamic load is unlikely to result in effective reduction of LV hypertrophy in obese. We review pathophysiology and prevalence of LV hypertrophy in obesity, with specific attention to LV geometric abnormalities and relations with body size.

Different pattern of carotid and myocardial changes according to left ventricular geometry in hypertensive patients

The relation between left ventricular (LV) hypertrophy and LV function is well known. However, less is known about the vascular changes influenced by LV geometry. We sought to investigate the relationship of LV geometry to carotid arterial and LV function. A total of 476 hypertensive patients were prospectively recruited. All subjects underwent echocardiography and carotid ultrasound. LV geometry is categorized into four groups according to relative wall thickness (RWT) and LV mass index (LVMI). Concentric LV geometry was associated with increased carotid intima-media thickness (IMT), β-stiffness, and lower strain. All of the carotid parameters showed a stepwise change according to RWT of LV, whereas LV function was worse in hypertrophic geometry, as reflected by significantly lower systolic mitral annular velocity, higher left atrial volume index and E/E' ratio (P<0.001). By multivariate analysis after adjustment for clinical and laboratory parameters, IMT was independently associated with RWT, whereas myocardial function was independently associated with LVMI. Carotid arterial function and IMT showed worse values in concentric geometry, whereas LV systolic and diastolic function were worse in hypertrophic geometry, suggesting a discrepancy between carotid arterial and LV function in hypertensive patients.

Natural history of concentric left ventricular geometry in community-dwelling older adults without heart failure during seven years of follow-up

Presence of concentric left ventricular (LV) geometry has important pathophysiologic and prognostic implications. However, little is known about its natural history in older adults. Of the 5,795 community-dwelling adults ≥65 years of age in the Cardiovascular Health Study, 1,871 without baseline heart failure had data on baseline and 7-year echocardiograms. Of these 343 (18%) had baseline concentric LV geometry (concentric remodeling 83%, concentric LV hypertrophy [LVH] 17%) and are the focus of the present study. LV geometry at year 7 was categorized into 4 groups based on LVH (LV mass indexed for height >51 g/m²·⁷) and relative wall thickness (RWT): eccentric hypertrophy (RWT ≤0.42 with LVH), concentric hypertrophy (RWT >0.42 with LVH), concentric remodeling (RWT >0.42 without LVH), and normal (RWT ≤0.42 without LVH). At year 7, LV geometry normalized in 57%, remained unchanged in 35%, and transitioned to eccentric hypertrophy in 7% of participants. Incident eccentric hypertrophy occurred in 4% and 25% of those with baseline concentric remodeling and concentric hypertrophy, respectively, and was associated with increased LV end-diastolic volume and decreased LV ejection fraction at year 7. Previous myocardial infarction and baseline above-median LV mass (>39 g/m²·⁷) and RWT (>0.46) had significant unadjusted associations with incident eccentric LVH; however, only LV mass >39 g/m²·⁷ (odds ratio 17.52, 95% confidence interval 3.91 to 78.47, p <0.001) and previous myocardial infarction (odds ratio 4.73, 95% confidence interval 1.16 to 19.32, p = 0.031) had significant independent associations. In conclusion, in community-dwelling older adults with concentric LV geometry, transition to eccentric hypertrophy was uncommon but structurally maladaptive.

Implications of persistent prehypertension for ageing-related changes in left ventricular geometry and function: the MONICA/KORA Augsburg study

BACKGROUND

It is unclear whether persistent prehypertension causes structural or functional alterations of the heart.

METHODS

We examined echocardiographic data of 1005 adults from a population-based survey at baseline in 1994/1995 and at follow-up in 2004/2005. We compared individuals who had either persistently normal (<120 mmHg systolic and <80 mmHg diastolic, n = 142) or prehypertensive blood pressure (120-139 mmHg or 80-89 mmHg, n = 119) at both examinations using multivariate regression modeling.

RESULTS

Over 10 years, left ventricular end-diastolic diameters were stable and did not differ between the two groups. However, the prehypertensive blood pressure group displayed more pronounced ageing-related increases of left ventricular wall thickness (+4.7 versus +11.9%, P < 0.001) and left ventricular mass (+8.6 versus +15.7%, P = 0.006). Prehypertension was associated with a raised incidence of left ventricular concentric remodeling (adjusted odds ratio 10.7, 95% confidence interval 2.82-40.4) and left ventricular hypertrophy (adjusted odds ratio 5.33, 1.58-17.9). The ratio of early and late diastolic peak transmitral flow velocities (E/A) decreased by 7.7% in the normal blood pressure versus 15.7% in the prehypertensive blood pressure group (P = 0.003) and at follow-up the ratio of early diastolic peak transmitral flow and early diastolic peak myocardial relaxation velocities (E/EM) was higher (9.1 versus 8.5, P = 0.031) and left atrial size was larger (36.5 versus 35.3 mm, P = 0.024) in the prehypertensive blood pressure group. Finally, the adjusted odds ratio for incident diastolic dysfunction was 2.52 (1.01-6.31) for the prehypertensive blood pressure group.

CONCLUSIONS

Persistent prehypertension accelerates the development of hypertrophy and diastolic dysfunction of the heart.

Left ventricular mass predicts heart failure not related to previous myocardial infarction: the Cardiovascular Health Study

AIMS

The relationship of left ventricular hypertrophy (LVH) to incident heart failure (HF) not attributable to myocardial infarction (MI) has not been defined. We assessed whether LVH is an independent predictor of MI-independent HF.

METHODS AND RESULTS

LVH was assessed by echocardiographic LV mass index (in g/m2.7) and excess of LV mass (eLVM, in % of the observed value) relative to the amount predicted by sex, stroke work, and height, using a prognostically validated equation in 2078 participants of Cardiovascular Health Study without prevalent MI and normal systolic function. Increasing eLVM was associated with progressively increasing left atrial dimension and concentric geometry, decreasing systolic (P < 0.0001), and diastolic function (P < 0.04). After adjustment for age, sex, obesity, diabetes, hypertension, and antihypertensive therapy, and accounting for by incident MI, hazard of HF increased by 1% for each 1% increase in eLVM and by 3% for each g/m2.7 increase in LV mass index (both P < 0.0001). The results were confirmed when also C-reactive protein and measures of systolic (endocardial shortening) and diastolic function (categories of E/A ratio) were added to the Cox models.

CONCLUSION

In an elderly population, LVH, measured as LV mass index or eLVM is an independent predictor of incident HF not related to prevalent or incident MI.

Myocardial hipertrophy in hypertensive patients with and without metabolic syndrome

Background/Aim. Beside arterial hypertension as the most important factor of a myocardial hypertension development, very important risk factors are obesity, hypercholesterolemia, insulin resistance, etc. The aim of the study was to examine the influence of metabolic syndrome (MetS) on left ventricular hypertrophy in patients with arterial hypertension. Methods. We checked medical records for 138 patients with arterial hypertension, and compared them with the control group of 44 normotensive subjects. The patients with arterial hypertension were divided into two groups considering the presence of MetS: with MetS (59 patients), and without MetS (79 patients). We defined MetS as presence of three (or more) within five criteria: central obesity (> 102 cm male, > 88 cm female), raised triglycerides (> 1.7 mmol/L, or drug treatment for elevated triglycerides), reduced high density lipoprotein (HDL) cholesterol (< 1.03 mmol/L male, < 1.3 mmol/L female), raised blood pressure (> 130 mmHg systolic, > 90 mmHg diastolic), raised fasting glucose (> 6.11 mmol/L, or drug treatment for elevated glucose level). In each group routine laboratory, echocardiography and 24-hour ambulatory blood pressure monitoring were performed. Results. We found statisticaly significant higher left ventricular mass in both subgroups hypertensive patients in comparison with the control group (p < 0.05). We did not find statistically significant difference (227.31?63.44 vs 219?59.5, p > 0.05) in left ventricular mass between these two groups of patients. In the patients with arterial hypertension and MetS we found hypertrophy more frequently than in the subgroup without MetS (43/57 vs 34/69, p < 0.001). Conclusion. Our results suggest that associated cardiometabolic risks increase the prevalence of myocardial hypertrophy, but do not influence left ventricular mass.

Left ventricular geometric patterns in newly presenting Nigerian hypertensives: an echocardiographic study

Background

Hypertension is a global problem and it is prevalent in Nigeria. Left ventricular hypertrophy is a major complication of hypertension with risk of sudden death and arrhythmias among others. Abnormal left ventricular geometric patterns also increase the burden of morbidity and mortality. It is therefore important to know the different left ventricular geometric patterns in Nigerian hypertensives because of their prognostic significance.

Methods

One hundred (100) newly presenting hypertensives (53 males and 47 females) and 100 controls (53 males and 47 females) were recruited for the study. All were subjected to clinical evaluation and full echocardiographic examination was performed according to the ASE recommendation. The relative wall thickness and the presence or absence of echocardiographic left ventricular hypertrophy were used to determine the various geometric patterns

Results

The mean age of the hypertensive subjects was 56.06 (± 7.68) years while that of the control subjects was 56.10 (± 7.68) years. There was no significant difference in the mean ages of the two groups. In the hypertensive subjects 28% had normal geometry, 26% had concentric remodeling, 28% had concentric hypertrophy and 18% had eccentric hypertrophy. In the control group, 86% had normal geometry, 11% had concentric remodeling, 3% had eccentric hypertrophy and none had concentric hypertrophy. There was statistical significance when the geometric patterns of the hypertensive and controls were compared (χ² = 74.30, p value < 0.0001).

Conclusion

The study showed that only 28% of the hypertensive subjects had normal LV geometric pattern while 86% of the normal subjects had normal geometry. There is need for longitudinal studies in order to prognosticate the various geometric patterns.

A genetic locus accentuates the effect of volume overload on adverse left ventricular remodeling in male and female rats

Although increased left ventricular (LV) mass is highly predictive of cardiovascular morbidity and mortality in humans, it has never been verified in an experimental model that naturally occurring alleles linked to increased LV mass under basal conditions also associate with worsened cardiovascular prognosis. Because we have shown previously that locus Cm24 on chromosome 5 was responsible for differences in LV mass between WKY and WKHA rats, we used WKY.WKHA-(D5Rat45-D5Rat245) congenic rats (where locus Cm24 has been transferred from WKHA into WKY rats) to test how naturally occurring gene variants present in Cm24 would, in addition to their effects under basal conditions, affect LV mass remodeling and/or function in the context of overload. Volume overload was induced in WKY, WKHA, and WKY.WKHA congenic rats by surgical creation of an aorto-caval fistula. In females, the fistula had no effect on the hearts of WKY rats, yet it induced dilated eccentric hypertrophy and isolated diastolic dysfunction in WKHA and WKY.WKHA congenic rats, along with signs of congestive heart failure. In males, the surgical maneuver induced only mild or inconsistent responses in WKY rats but had much more pronounced effects in WKHA and WKY.WKHA congenic rats. Altogether, our data show that a genetic locus that induces, under basal conditions, either mild or no concentric LV remodeling in either male or female rats, respectively, associates with LV dilatation and dysfunction in both sexes when the hearts are additionally challenged.

Reduced left ventricular functional reserve in hypertensive patients with preserved function at rest

In many hypertensive patients, left ventricular pump function is normal at rest but abnormal during exercise. Myocardial dysfunction or altered left ventricular loading may be responsible for this finding. To verify the hypothesis of impaired myocardial functional reserve in the hypertensive heart, we assessed the response of stress-adjusted midwall shortening to graded, low-dose dobutamine infusion in hypertensive subjects with normal midwall shortening at rest. Sixty-five subjects (45 never treated hypertensive subjects and 20 normotensive volunteers comparable for age) received dobutamine at 1, 2, 3, 4, and 5 microg x kg(-1) x min(-1) for 5-minute steps; within this range of infusion rates, heart rate and systemic blood pressure were stable. Two-dimensional, M-mode, and Doppler echocardiography were performed at baseline and at the end of each step. In normotensive controls, midwall shortening increased from baseline during 2 microg x kg(-1) x min(-1) dobutamine by an average of 16+/-4.5% (P<0.01); a value of 2 standard deviations below this mean response was taken as the lower limit of normal. In the hypertensive subjects, 24 had a normal midwall shortening response to dobutamine at this dose (group I) and 21 had a subnormal response (group II). Whereas blood pressure and left ventricular mass were similar in group II and group I, the former had greater relative wall thickness (P<0.01) than the latter. beta-adrenergic stimulation by very-low-dose dobutamine unmasks subtle impairment of myocardial functional reserve in hypertensive subjects with normal myocardial performance at rest. This alteration seems to be related mainly to increase in left ventricular relative wall thickness.

Evaluation of Concentric Left Ventricular Geometry in Humans

There might be limitations in identifying concentric left ventricular (LV) geometry by ratio of diastolic posterior wall thickness (WT p ) to cavity radius, defined as relative wall thickness (RWT p ). This study has been designed to evaluate age effects on RWT p . WT p , mean of septal thickness and WT p (WT m ), and cavity radius were cross-sectionally evaluated in 766 1- to 85-year-old, normotensive, nonobese subjects and 331 hypertensive Italians (used as a test series). RWT p ≥0.43 defined “traditional” concentric LV geometry. The ratios WT m /radius (RWT m ) and RWT p increased by 0.005 and 0.006 per year of age in the age stratum up to 17 years and by 0.002 in the older age stratum (18 years or older; all P <0.0001). Thus, RWT m and RWT p were normalized to average age in both age strata (10 and 46 years) by age-specific regression coefficients. The 90th and 95th percentiles of age-normalized RWT p or RWT m were 0.40 and 0.42 or 0.41 and 0.43, respectively, in adults and 0.36 and 0.39 or 0.36 and 0.38, respectively in young subjects. In hypertensive subjects, traditional RWT p cutoff identified 74 subjects (22%) with concentric LV geometry; by 95th or 90th normal percentiles, normalized RWT m identified 112 (34%), or 149 (45%) subjects with concentric LV geometry, and normalized RWT p 29% and 39%, respectively (all P <0.0001 versus unadjusted RWT p ). Thus, prevalence of concentric LV geometry increases with age-normalized RWT. Accordingly, we suggest that concentric LV hypertrophy be defined by coexistence of high LV mass with age-normalized RWT m >0.41 or RWT p >0.40. Further studies are required to establish prognostic implications of our findings.