Echocardiographic assessment of cardiac anatomy and function in hypertensive subjects

Austrian consensus statement on the diagnosis and management of hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is the most common inherited heart disease that is characterized by left ventricular hypertrophy unexplained by secondary causes. Based on international epidemiological data, around 20,000-40,000 patients are expected to be affected in Austria. Due to the wide variety of clinical and morphological manifestations the diagnosis can be difficult and the disease therefore often goes unrecognized. HCM is associated with a substantial reduction in quality of life and can lead to sudden cardiac death, especially in younger patients. Early and correct diagnosis, including genetic testing, is essential for comprehensive counselling of patients and their families and for effective treatment. The latter is especially true as an effective treatment of outflow tract obstruction has recently become available in the form of a first in class cardiac myosin ATPase inhibitor, as a noninvasive alternative to established septal reduction therapies. The aim of this Austrian consensus statement is to summarize the recommendations of international guidelines with respect to the genetic background, pathophysiology, diagnostics and management in the context of the Austrian healthcare system and resources, and to present them in easy to understand algorithms.

Mechanical dyssynchrony and diastolic dysfunction are common in LVH: a pilot correlation study using Doppler echocardiography and CZT gated-SPECT MPI

Hypertrophic cardiomyopathy (HCM) is an often under-diagnosed cause of left ventricular hypertrophy (LVH). It affects 1/500 of the population, is the most commonly inherited cardiovascular disorder, and can present in apical, concentric, or septal forms. Although most patients are asymptomatic, sudden cardiac death can be the initial presentation of HCM. By retrospectively enrolling patients suspected of having three different types of HCM in the absence of epicardial coronary stenosis, we aimed to examine systolic and diastolic dysfunction and perfusion abnormalities using both Doppler echocardiography and state-of-the-art gated single-photon emission computerized tomography (SPECT) myocardial perfusion imaging (MPI) with a cadmium-zinc-telluride camera and thallium-201. Both regional perfusion and gated SPECT parameters were collected in addition to diastolic parameters from Doppler echocardiography. The results showed that mild ischemia was common in patients suspected of having HCM, with a mean summed stress score of 4.7 ± 4.9 (score 0–4 in 17-segment model). The patients with HCM were associated with discernible left ventricular mechanical dyssynchrony, especially those with the apical form. In addition, diastolic dysfunction was prevalent and early to late ventricular filling velocity ratios were significantly different between groups. By combining gated-MPI and Doppler data, the trivial functional changes in HCM may be identified.

Validity of electrocardiographic criteria for increased left ventricular mass in young patients in the general population

AIM

To investigate validity of electrocardiographic (ECG) criteria for left ventricular hypertrophy (LVH) in young adults.

METHODS

Retrospectively, echocardiograms showing LVH and concomitant electrocardiograms were collected in patients 18 to 39 years old. A control group of patients without LVH was collected. Using echocardiogram as the gold standard, electrocardiograms were analyzed using common voltage criteria.

RESULTS

Study included 100 subjects (52% male, mean age = 28 ± 6.8 years, 96% Hispanic or African-American) with 50% LVH prevalence. Sensitivity and specificity for Sokolow-Lyon criteria were 24% (95%CI: 13.5%-38.4%) and 88% (95%CI: 74.9%-95%). For Cornell criteria, sensitivity was 32% (95%CI: 19.9%-46.8%) and specificity 98% (95%CI: 87.9%-99.8%). For R in aVL criteria, sensitivity was 12% (95%CI: 4.9%-25%) and specificity 100% (95%CI: 91.1%-100%).

CONCLUSION

In young adults common ECG voltage criteria have low sensitivities and high specificities similar to other age groups. Low sensitivities preclude these ECG criteria from serving as effective screening tests.

Assessment of left ventricular ejection force and sympathetic skin response in normotensive and hypertensive subjects: A double-blind observational comparative case-control study

Background

Pathophysiology of essential hypertension remains obscure. Correlation among ventricular ejection force, sympathetic activity, and hypertension is less clearly narrated in hypertensive subjects.

Aims and objectives

To assess correlation among ventricular ejection force, sympathetic activity, and hypertension in hypertensive subjects, and to be compared with normotensive subjects.

Methods

This is a case–control study to assess left ventricular ejection force (LVEF) and sympathetic skin response, in normotensive (group 1; control), and hypertensive subjects (group 2; cases). 100 cases were selected. Subjects having stages 1 and 2 hypertension were categorized in groups 2A and 2B, respectively. LVEF was calculated by using echocardiography observing aortic acceleration time (AT) and peak systolic velocity. Comparison among groups was done by using one-way ANOVA.

Results

Both groups were comparable. In group 2, 60 cases had stage 1 hypertension and 40 had stage 2 hypertension. Significantly short AT and significantly high LVEF were found in hypertension (groups 2A and 2B) (p < 0.0001). Sympathetic activity was high in group 2A (p < 0.0001). Stroke volume (SV) was high in group 2B (p < 0.0001).

Conclusion

Stage 1 hypertension is a stage of increased sympathetic activity, leading to increased LVEF and hypertension (resetting of baroreceptors); stage 2 hypertension is a stage of normal sympathetic activity, increased LVEF, increased SV, and hypertension (possibly a stage of shift of renal equilibrium curve/renal output curve and blood pressure to a newer level).

The Relationship Between Aortic Root Size and Hypertension: An Unsolved Conundrum

Thoracic aortic aneurysms rupture and dissection are among the most devastating vascular diseases, being characterized by elevated mortality, despite improvements in diagnostic imaging and surgical techniques.An increased aortic root diameter (ARD) represents the main risk factor for thoracic aortic dissection and rupture and for aortic valve regurgitation.Even though arterial hypertension is commonly regarded as a predisposing condition for the development of thoracic aorta aneurysms, the role of blood pressure (BP) as determinant of aortic root enlargement is still controversial. The use of different methods for indexation of ARD may have in part contributed to the heterogeneous findings obtained in the investigations exploring the relationships between ARD and BP. Indeed, the best methods for ARD indexation, as well as the normal values of aortic root size, are still a matter of debate.Several non-hemodynamic factors influence ARD, including age, gender, and anthropometric variables, such as height, weight and their derivatives body surface area (BSA) and body mass index. Of these factors, anthropometric variables have the greatest impact.Several studies documented an association between ARD enlargement, assessed by echocardiography, and some indices of hypertensive target organ damage such as left ventricular hypertrophy, diastolic dysfunction, and carotid intima-media thickening. Recently, we found that ARD, expressed either as absolute values or normalized for BSA (ARD/BSA) or height (ARD/H), was significantly greater in hypertensive subjects with chronic kidney disease (CKD) when compared to their counterparts with normal renal function. Moreover, at univariate analyses estimated glomerular filtration rate (eGFR) showed significant inverse correlations with ARD not indexed and with ARD/BSA and ARD/H. Taking into account the effect of age, sex, duration of hypertension and other potentially confounding factors, in multiple regression analyses, only the association of GFR with ARD/H and that between GFR and ARD/BSA remained statistically significant. The receiver-operating characteristic curve analysis revealed that an estimated GFR of about 50 ml/min/1.73 m² represents the better threshold to distinguish hypertensive patients with dilated aortic root from those with a normal one.Some population-based studies showed that an enlarged ARD might predict an adverse prognosis, even in absence of aneurysmatic alterations.In the Cardiovascular Health Study, a dilated aortic root was independently associated with an increased risk for stroke, cardiovascular and total mortality in both sexes and with incident congestive heart failure only in men. The relationship between ARD and heart failure has been observed also in the Framingham Heart Study. More recently, the PAMELA (Pressioni Arteriose Monitorate E Loro Associazioni) study demonstrated an independent relationship of ARD/H with incident cardiovascular morbidity and mortality.Although the relationship between BP and aortic root size is still a matter of debate, increasing evidence seems to support the notion that aortic root dilatation, even in absence of aneurysmatic alterations, may be regarded as an hypertensive organ damage paralleling other preclinical markers whose unfavourable prognostic significance is firmly established. Future studies are needed to assess whether or not antihypertensive therapy is able to reduce aortic root dimension and the increased risk associated with its enlargement.

Hypertensive cardiomyopathy: A clinical approach and literature review

Hypertensive cardiomyopathy (HTN-CM) is a structural cardiac disorder generally accompanied by concentric left ventricular hypertrophy (LVH) associated with diastolic or systolic dysfunction in patients with persistent systemic hypertension. It occurs in the absence of other cardiac diseases capable of causing myocardial hypertrophy or cardiac dysfunction. Persistent systemic hypertension leads to structural and functional myocardial abnormalities resulting in myocardial ischemia, fibrosis, and hypertrophy. HTN-CM is predominantly a disease of impaired relaxation rather than impaired contractility, so patients are usually asymptomatic during resting conditions. However, their stiff left ventricles become incapable of handling increased blood volume and cannot produce appropriate cardiac output with the slight change of circulating volume that may occur during exercise. Importantly, the accompanying LVH is itself a risk factor for mortality and morbidity. Therefore, early detection of LVH development in patients with hypertension (referred to as HTN-CM) is critical for optimal treatment. In addition to pathological findings, echocardiography and cardiac magnetic resonance imaging are ideal tools for the diagnosis of HTN-CM. Timely diagnosis of this condition and utilization of appropriate treatment are required to improve morbidity and mortality in hypertensive patients. This review article presents an overview of the multidimensional impact of myocardial disorder in patients with hypertension. Relevant literature is highlighted and the effects of hypertension on cardiac hypertrophy and heart failure development are discussed, including possible therapeutic options.

Utilizing ECG-Based Heartbeat Classification for Hypertrophic Cardiomyopathy Identification

Hypertrophic cardiomyopathy (HCM) is a cardiovascular disease where the heart muscle is partially thickened and blood flow is (potentially fatally) obstructed. A test based on electrocardiograms (ECG) that record the heart electrical activity can help in early detection of HCM patients. This paper presents a cardiovascular-patient classifier we developed to identify HCM patients using standard 10-second, 12-lead ECG signals. Patients are classified as having HCM if the majority of their recorded heartbeats are recognized as characteristic of HCM. Thus, the classifier's underlying task is to recognize individual heartbeats segmented from 12-lead ECG signals as HCM beats, where heartbeats from non-HCM cardiovascular patients are used as controls. We extracted 504 morphological and temporal features—both commonly used and newly-developed ones—from ECG signals for heartbeat classification. To assess classification performance, we trained and tested a random forest classifier and a support vector machine classifier using 5-fold cross validation. We also compared the performance of these two classifiers to that obtained by a logistic regression classifier, and the first two methods performed better than logistic regression. The patient-classification precision of random forests and of support vector machine classifiers is close to 0.85. Recall (sensitivity) and specificity are approximately 0.90. We also conducted feature selection experiments by gradually removing the least informative features; the results show that a relatively small subset of 264 highly informative features can achieve performance measures comparable to those achieved by using the complete set of features.

Determinants of discrepancies in detection and comparison of the prognostic significance of left ventricular hypertrophy by electrocardiogram and cardiac magnetic resonance imaging

Despite the low sensitivity of the electrocardiogram (ECG) in detecting left ventricular hypertrophy (LVH), ECG-LVH is known to be a strong predictor of cardiovascular risk. Understanding reasons for the discrepancies in detection of LVH by ECG versus imaging could help improve the diagnostic ability of ECG. We examined factors associated with false-positive and false-negative ECG-LVH, using cardiac magnetic resonance imaging (MRI) as the gold standard. We also compared the prognostic significance of ECG-LVH and MRI-LVH as predictors of cardiovascular events. This analysis included 4,748 participants (mean age 61.9 years, 53.5% females, 61.7% nonwhites). Logistic regression with stepwise selection was used to identify factors associated with false-positive (n = 208) and false-negative (n = 387), compared with true-positive (n = 208) and true-negative (n = 4,041) ECG-LVH, respectively. A false-negative ECG-LVH status was associated with increased odds of Hispanic race/ethnicity, current smoking, hypertension, increased systolic blood pressure, prolongation of QRS duration, and higher body mass index and with lower odds of increased ejection fraction (model-generalized R(2) = 0.20). A false-positive ECG-LVH status was associated with lower odds of black race, Hispanic race/ethnicity, minor ST-T abnormalities, increased systolic blood pressure, and presence of any major electrocardiographic abnormalities (model-generalized R(2) = 0.29). Both ECG-LVH and MRI-LVH were associated with an increased risk of cardiovascular disease events (hazard ratio 1.51, 95% confidence interval 1.03 to 2.20 and hazard ratio 1.81, 95% confidence interval 1.33 to 2.46, respectively). In conclusion, discrepancy in LVH detection by ECG and MRI can be relatively improved by considering certain participant characteristics. Discrepancy in diagnostic performance, yet agreement on predictive ability, suggests that LVH by ECG and LVH by imaging are likely to be two distinct but somehow related phenotypes.

Correlation between Left Ventricular Mass Index and Calcium Metabolism in Patients with Essential Hypertension

OBJECTIVE

To determine the correlation between left ventricular mass index and calcium metabolism in patients with essential hypertension.

STUDY DESIGN

Cross sectional case-control study.

MATERIAL AND METHODS

Twenty-seven patients with essential hypertension and 20 healthy individuals were compared with respect to calciotropic hormones, left ventricular mass index (LVMI), and urinary and serum biochemical parameters. The correlations between parathormone, vitamin D, and calcitonin levels and LVMI and blood pressure elevation were determined.

RESULTS

The parathormone level was significantly higher (p=0.006) and vitamin D level was significantly lower (p=0.01) in the patient group compared with the control group. However, the two groups were similar in terms of albumin-corrected calcium levels, which were within the normal range (p=0.988). The serum sodium (p=0.014) and urinary calcium (p=0.003) levels and LVMI (p<0.01) were also significantly higher in the patient group. No significant correlations were determined between ambulatory blood pressure and parathormone and vitamin D levels, but a significant correlation was found between LVMI and parathormone level (p=0.06) in hypertensive patients.

CONCLUSION

Essential hypertension alters calcium metabolism, causing calciuresis by hypernatremia. Parathormone release increases to compensate for this, and leads to protein synthesis, which in turn provokes the development of myocardial hypertrophy.

Imaging in hypertensive heart disease

Hypertensive heart disease is the target organ response to arterial hypertension. Left ventricular hypertrophy represents an important predictor for cardiovascular events. Myocardial fibrosis, a common end point in hypertensive heart disease, has been linked to the development of left ventricular hypertrophy and diastolic dysfunction. Echocardiography is clinically useful in the detection of left ventricular hypertrophy and the assessment of diastolic function. Although echocardiography is more widely available, cardiac magnetic resonance has been demonstrated to be more reproducible for the estimation of left ventricular mass. Future developments in cardiac magnetic resonance techniques may facilitate the quantification of diffuse fibrosis that occurs in hypertensive heart disease. Thus, advances in cardiac imaging provide comprehensive, noninvasive tools for imaging left ventricular hypertrophy, diastolic dysfunction, myocardial fibrosis and ischemia observed in hypertensive heart disease. The objective of this article is to summarize the state-of-the-art and the future of multimodality imaging of hypertensive heart disease.

Correlation of echocardiographic findings with cerebral infarction in elderly adults: the AGES-Reykjavik study

BACKGROUND AND PURPOSE

Chronic effects of hypertension may be observed in multiple end organs. Previous reports suggest that cardiovascular morphological features can mirror cerebral infarction. In this cross-sectional analysis of elderly subjects, we investigated the relationship of a comprehensive set of echocardiographic measures with cerebral infarction detected by MRI.

METHODS

We compared echocardiographically determined left ventricular (LV) mass, left atrial volume, aortic root diameter, mitral annular calcification, and measures of diastolic function with cerebral infarction determined by MRI using logistic regression in a random sample drawn from the Age Gene/Environment Susceptibility-Reykjavik Study cohort. The model was first adjusted for age and gender, and then for age, gender, and vascular risk factors.

RESULTS

Among 692 subjects aged 75 (standard deviation, 6) years, 28% had at least 1 cerebral infarct. When adjusted for age and gender, the presence of cerebral infarction was modestly related to LV mass (odds ratio [OR], 1.01; 95% confidence interval [CI], 1.00-1.02) and left atrial volume (OR, 1.03; 95% CI, 1.01-1.05), as well as the lowest quartile of early-to-late pulsed Doppler velocity ratio (early-to-late pulsed Doppler velocity ratio <0.75; OR, 1.87; 95% CI, 1.22-2.87). The latter relation remained significant after adjustment for vascular risk factors and LV ejection fraction (OR, 1.82; 95% CI, 1.16-2.86).

CONCLUSIONS

Of all echocardiographic parameters, LV filling abnormality as indicated by low early-to-late pulsed Doppler velocity ratio displayed the strongest association with cerebral infarction and this relationship was independent of vascular risk factors. This simple marker of cerebral infarction may be useful when evaluating older patients.

Association of the beta-1 adrenergic receptor carboxyl terminal variants with left ventricular hypertrophy among diabetic and non-diabetic survivors of acute myocardial infarction

Background

The beta-1 adrenergic receptor (β₁AR) plays a fundamental role in the regulation of cardiovascular functions. It carries a nonsynonymous single nucleotide polymorphism in its carboxyl terminal tail (Arg389Gly), which has been shown to associate with various echocardiographic parameters linked to left ventricular hypertrophy (LVH). Diabetes mellitus (DM), on the other hand, represents a risk factor for LVH. We investigated the possible association between the Arg389Gly polymorphism and LVH among non-diabetic and diabetic acute myocardial infarction (AMI) survivors.

Methods

The study population consisted of 452 AMI survivors, 20.6% of whom had diagnosed DM. Left ventricular parameters were measured with two-dimensional guided M-mode echocardiography 2-7 days after AMI, and the Arg389Gly polymorphism was determined using a polymerase chain reaction-restriction fragment length polymorphism assay.

Results

The Arg389 homozygotes in the whole study population had a significantly increased left ventricular mass index (LVMI) when compared to the Gly389 carriers (either Gly389 homozygotes or Arg389/Gly389 heterozygotes) [62.7 vs. 58.4, respectively (p = 0.023)]. In particular, the Arg389 homozygotes displayed thicker diastolic interventricular septal (IVSd) measures when compared to the Gly389 carriers [13.2 vs. 12.3 mm, respectively (p = 0.004)]. When the euglycemic and diabetic patients were analyzed separately, the latter had significantly increased LVMI and diastolic left ventricular posterior wall (LVPWd) values compared to the euglycemic patients [LVMI = 69.1 vs. 58.8 (p = 0.001) and LVPWd = 14.2 vs. 12.3 mm (p < 0.001), respectively]. Furthermore, among the euglycemic patients, the Arg389 homozygotes displayed increased LVMI and IVSd values compared to the Gly389 carriers [LVMI = 60.6 vs. 56.3, respectively (p = 0.028) and IVSd = 13.1 vs. 12.0 mm, respectively (p = 0.001)]. There was no difference in the LVMI and IVSd values between the diabetic Arg389 homozygotes and Gly389 carriers.

Conclusions

The data suggest an association between the β₁AR Arg389Gly polymorphism and LVH, particularly the septal hypertrophy. The Arg389 variant appears to confer a higher risk of developing LVH than the corresponding Gly389 variant among patients who have suffered AMI. This association cannot be considered to be universal, however, since it does not appear to exist among diabetic AMI survivors.

Pre-clinical diabetic cardiomyopathy: prevalence, screening, and outcome

AIMS

Diabetic cardiomyopathy, characterized by left ventricular (LV) dysfunction and LV hypertrophy independent of myocardial ischaemia and hypertension, could contribute to the increased life-time risk of congestive heart failure seen in patients with diabetes. We assessed prospectively the prevalence, effectiveness of screening methods [brain natriuretic peptide (BNP) and C-reactive protein in combination with clinical parameters], and outcome of pre-clinical diabetic cardiomyopathy.

METHODS AND RESULTS

We studied 100 adults (mean age 57.4 +/- 10.2 years, 44% females) with diabetes and no previous evidence of structural heart disease. By echocardiography, diabetic cardiomyopathy was present in 48% of patients. Screening with combinations of clinical parameters (gender, systolic blood pressure, and body mass index), but not BNP, resulted in high negative predictive values for diabetic cardiomyopathy. During a mean follow-up of 48.5 +/- 9.0 months, in the groups with and without diabetic cardiomyopathy, 12.5 vs. 3.9% (P < 0.2) patients died or experienced cardiovascular events and 37.5 vs. 9.6% (P < 0.002) had a deterioration in NYHA functional class. Overall event-free survival was 54 vs. 87% (P = 0.001) in the groups with and without diabetic cardiomyopathy, respectively. Brain natriuretic peptide was an independent predictor of events [odds ratio 3.5 (1.1-10.9), P = 0.02].

CONCLUSION

Pre-clinical diabetic cardiomyopathy is common. Screening with combinations of simple clinical parameters, but not BNP, can be useful to identify those patients needing further evaluation. Patients with pre-clinical diabetic cardiomyopathy are at increased risk for functional deterioration and possibly cardiovascular events during follow-up. Brain natriuretic peptide was shown to be an independent predictor of future events.

Normalization of left ventricular dysfunction in systemic hypertension

BACKGROUND

In hypertensive heart disease, it is uncertain whether the impairment of left ventricular (LV) systolic function might be reverted by antihypertensive treatment.

HYPOTHESIS

This study was undertaken to address the likelihood of recovery of LV dysfunction and to identify factors potentially related.

METHODS

Twenty-six patients with primary (n = 16) and renovascular (n = 10) hypertension participated in the study and were classified into Groups A (n = 12) and B (n = 14) according to normalization or persistent left ventricular dysfunction (fractional shortening < 0.30) after 36 weeks of follow-up. All patients received standard medical therapy and appropriate procedures for renovascular disease correction. Logistic regression analysis was used to identify variables associated with recovery.

RESULTS

Patients in Group A compared with those in Group B were younger (41 +/- 14 vs. 52 +/- 10 years; p < 0.05), had a greater frequency of renovascular hypertension (8 vs. 2; p < 0.05), showed shorter LV end-diastolic (54 +/- 5 vs. 61 +/- 8 mm; p < 0.05) and end-systolic dimensions (41 +/- 6 vs. 49 +/- 9 mm; p < 0.05), and lower mass index (215 +/- 64 vs. 261 +/- 47 g.m-2; p < 0.05) before treatment, whereas fractional shortening (0.24 +/- 0.4 vs. 0.20 +/- 0.5; p > 0.05) and diastolic blood pressure (116 +/- 12 vs. 122 +/- 19 mmHg; p > 0.05) were similar. On follow-up, Group A patients showed lower diastolic blood pressure (89 +/- 15 vs. 105 +/- 20 mmHg; p < 0.05) and mass index (142 +/- 34 vs. 222 +/- 40 g.m-2; p < 0.05). Logistic regression analysis identified systolic dimension and renovascular hypertension as factors associated with fractional shortening normalization.

CONCLUSION

The recovery of LV dysfunction is expected to occur most likely in patients with renovascular hypertension and the shortest systolic dimensions.

Left atrial size in 164 hypertensive patients: an echocardiographic and ambulatory blood pressure study

BACKGROUND

Left atrial enlargement (LAE) is associated with an increased risk of death and cardiovascular (CV) hospitalization. Whether or not LAE reflects early structural change from hypertension is unclear.

HYPOTHESIS

The aim of this study was to evaluate the relationship between LA size, 24-h blood pressure measurements, age, body mass index (BMI), and left ventricular mass index (LVMI) in hypertensive patients.

METHODS

We studied 164 outpatients (age range 30-76 years, 73 men and 91 women) with mild to moderate hypertension. Physical examination, electrocardiogram, noninvasive blood pressure monitoring (ABPM), Doppler echocardiogram were performed. Left ventricular mass index and LA dimensions were calculated. The sample was divided by age (< 60 and > or = 60 years).

RESULTS

Left ventricular hypertrophy (LVH) was present in 45% of patients aged < 60 years and in 70% of patients aged > or = 60 years (p = 0.002). Left atrial enlargement (> 4 cm) was present in 35% of elderly and in 24% of young patients (p = 0.31), and in 36% of patients with and 21% of patients without LVH (p = 0.0057). There was no significant difference in the younger patients with and without LVH. The incidence of obesity was low (31%) in the whole sample. The percentage of overweight in the elderly patients with LVH and higher LA size was equally low. Multivariate analysis showed age (p = 0.044) and LVMI (p = 0.002) as the only significant predictors of LA enlargement.

CONCLUSION

Since LAE is associated with a high risk of death and CV hospitalization, we emphasize the importance of development and use of drugs that inhibit LVH.

Symmetric and asymmetric left ventricular hypertrophy in patients with end-stage renal failure on long-term hemodialysis

BACKGROUND

Patients with end-stage renal disease on regular hemodialysis have an increased prevalence of left ventricular (LV) hypertrophy that is associated with morbidity and mortality. Asymmetric septal hypertrophy and impairment of LV outflow can occur in these patients and may contribute to adverse outcomes. More insight into the prevalence, extent, geometry, and promoting factors of LV hypertrophy is important.

METHODS

An unselected group of 62 patients (31 women), aged 55 +/- 14 years, on maintenance hemodialysis was investigated by Doppler echocardiography. Eight patients with valvular heart disease were excluded from further analysis. We assessed prevalence of LV hypertrophy and asymmetric septal hypertrophy, as well as parameters of LV geometry and LV filling and outflow dynamics.

RESULTS

Prevalence of LV hypertrophy was 65%. Patients were analyzed according to LV mass and geometry. Mean LV mass index was normal (105 +/- 17 g/m2) in Group 1 without LV hypertrophy (n = 19); it was markedly elevated in Group 2 (symmetric hypertrophy, n = 22) and Group 3 (asymmetric hypertrophy with systolic anterior movement of mitral valve, n = 7), and highest (191 +/- 54 g/m2) in Group 4 (asymmetric hypertrophy without systolic anterior movement of mitral valve, n = 6, p < 0.001). Age, body mass index, and duration of hypertension were associated with LV hypertrophy and asymmetric septal hypertrophy (p = 0.01). Group 3 with systolic anterior motion of mitral valve had the smallest end-diastolic LV diameters (p = 0.02); increased heart rates, and increased ejection velocities in the LV outflow tract (p = 0.03, and p = 0.005, respectively, vs. Groups 1, 2, and 4) which pointed to an impairment of LV outflow.

CONCLUSIONS

Symmetric LV hypertrophy and asymmetric septal hypertrophy are frequent in patients on maintenance hemodialysis. Predictors for LV hypertrophy were age and body mass index, and, particularly for asymmetric septal hypertrophy, age and hypertension duration. Volume withdrawal during hemodialysis may lead to symptomatic hypotension due to dynamic obstruction in some patients with severe asymmetric septal hypertrophy.

Do hypertensive individuals have enlarged aortic root diameters? Insights from studying the various subtypes of hypertension

BACKGROUND

Aortic root diameter (AoD) increases with aging and is related to body size. AoD is also presumed to increase in hypertension. In prior studies, however, after adjusting for age and body size, AoD did not differ between hypertensive and normotensive (NT) individuals. Hypertension is a heterogeneous condition with various subtypes that differ in pathophysiology and age distribution. We assessed whether AoD differs among subjects with the various subtypes of hypertension and nonhypertensive individuals.

METHODS

In 1,256 volunteers aged 30-79 years (48% women, 48% hypertensive; all untreated), AoD was measured at the sinuses of Valsalva with transthoracic echocardiography. Using cutoff values based on the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, subjects were identified as NT (23%), or prehypertensive (PH, 29%), or as having isolated diastolic (IDH, 6%), isolated systolic (ISH, 12%), or systolic-diastolic (SDH, 30%) hypertension. Groups were compared using analysis of variance with Bonferroni's correction.

RESULTS

AoD increased with age and body surface area (BSA) in both men (r = 0.25 and 0.19, respectively) and women (r = 0.30 and 0.22, respectively) (all P < 0.0001). In men, those identified as having IDH, ISH, and SDH each had a 6% larger AoD than NT individuals (all P < 0.05). In women, those identified with ISH and SDH had a 10 and 8% larger AoD than NT individuals, respectively (all P < 0.05). In both sexes, after indexing to BSA, only ISH individuals exhibited larger AoD compared with NT individuals (both P < 0.05). But, with further adjustment for age, these differences were no longer observed.

CONCLUSIONS

Even when the subtypes of hypertension are examined separately, age and BSA, not hypertension status, account for the AoD differences between NT and hypertensive subjects.

Irbesartan and atenolol improve diastolic function in patients with hypertensive left ventricular hypertrophy

OBJECTIVES AND DESIGN

An abnormal diastolic filling is common in hypertensive left ventricular (LV) hypertrophy, a condition that may lead to heart failure and death. The renin-angiotensin-aldosterone system has been implicated in the development of LV hypertrophy. This study examines the effects of 48 weeks of double-blind treatment with the AT1 receptor blocker irbesartan and the beta-blocker atenolol on diastolic function.

METHODS

Diastolic function was evaluated in 115 hypertensive patients with LV hypertrophy by Doppler echocardiography mitral inflow velocities calculated from the peak of early (E) and peak of late (A) diastolic velocities (E/A ratio), the E-wave deceleration time, the isovolumic relaxation time, the pulmonary venous flow velocity, and by the atrioventricular valve plane displacement method.

RESULTS

By similar reductions in blood pressure both groups progressively reduced the LV mass index, with a greater reduction in the irbesartan group (P = 0.024). Diastolic function was improved similarly by irbesartan and atenolol; for example, the E/A ratio by 12 and 14% (P = 0.022 and P < 0.001), and the pulmonary venous flow velocity by 10 and 7% (P = 0.036 and P = 0.001), respectively. The isovolumic relaxation time was improved by irbesartan (P = 0.040) only, and was related to changes in LV geometry (P < 0.001). For atenolol, improvement in diastolic function was associated only with the reduction in blood pressure (P = 0.048). An improvement in diastolic function appeared greater in concentric LV hypertrophy than in eccentric LV hypertrophy.

CONCLUSIONS

Treatment based on atenolol or irbesartan improves diastolic function in patients with hypertensive LV hypertrophy to the same degree, but through different mechanisms.

Heritability of left atrial size in the Tecumseh population

BACKGROUND

Little is known about the determinants of atrial size, and no study has analyzed whether genetic factors are involved in the pathogenesis of LA enlargement.

MATERIALS AND METHODS

We studied the heritability of echocardiographic left atrial size in 290 parents from the Tecumseh Blood Pressure Study and 251 children from the Tecumseh Offspring Study. All data from the parents and children were obtained at the same field office in Tecumseh, USA. Left atrial dimension was determined echocardiographically in accordance with American Society of Echocardiography guidelines with the use of leading-edge-to-leading-edge measurements of the maximal distance between the posterior aortic root wall and the posterior left atrial wall at end systole.

RESULTS

For correlation between the left atrial dimensions of the parents and their offspring, several models were generated to adjust the atrial dimensions in both groups for an increasing number of clinical variables. After removing the effect of age, gender, height, weight, skinfold thickness, and systolic blood pressure, parent-child correlation for left atrial size was 0.19 (P = 0.007). Further adjustment for left ventricular mass and for measuring left ventricular diastolic function increased the correlation to 0.25 (P = 0.001).

CONCLUSIONS

The present data indicate that heredity can explain a small but definite proportion of the variance in left atrial dimension.

Angiotensin II as a cardiovascular risk factor

A renin-angiotensin level that is inappropriately high for the systemic blood pressure and the state of sodium balance is now recognized to be one of the modifiable cardiovascular risk factors. Angiotensin acts both as a circulating hormone and as a locally acting paracrine/autocrine/intracrine factor. The adverse effects of angiotensin on the heart include the mechanical results of elevated resistance to the pumping function of the myocardium, as well as the effects of neurohumoral abnormalities on various cardiac structures. In addition, cardiac damage follows acute ischaemic injury or chronic energy starvation due to coronary artery disease, attributable to either mechanical obstruction (atherosclerotic and/or thrombotic) or functional stenosis (vasospasm). Activation of the renin-angiotensin system has several haemodynamic and humoral consequences, all of which may damage the myocardium. These include acute myocardial ischaemia, left-ventricular hypertrophy, arrhythmias, alterations in the coagulation-fibrinolysis equilibrium, increased oxidative stress, and pro-inflammatory activity. A brief review of some of the mechanisms by which activation of the renin-angiotensin system can inflict damage on the heart is presented.

Relationship of clinic, ambulatory, and laboratory stress blood pressure to left ventricular mass in overweight men and women with high blood pressure

OBJECTIVE

This study was designed to evaluate the relationship between left ventricular (LV) mass and blood pressure (BP) recorded in the following contexts: in the clinic, using standard auscultatory procedures, during a typical day using ambulatory BP monitoring, and in the laboratory environment during behavioral stress testing.

METHODS

Ninety-seven men and women with clinic systolic blood pressure (SBP) of 130 to 180 mm Hg and/or diastolic blood pressure (DBP) of 85 to 110 mm Hg and mild to moderate obesity were included in the study. Laboratory stressors included the following tasks: Public Speaking; Anger Interview; Mirror Trace; and Cold Pressor. LV mass was measured using echocardiography and adjusted for body size by dividing by height(2.7) to yield LV mass index (LVMI).

RESULTS

LVMI was positively correlated with clinic SBP (r = 0.24, p <.05), ambulatory SBP (r = 0.34, p <.01), and aggregated laboratory stress SBP (r = 0.28, p <.01). Of the individual stressors, only SBP responses to the Mirror Trace and Cold Pressor tasks were independently correlated with LVMI (r = 0.35 and 0.34, respectively, p values <.01). Hierarchical regression analyses revealed that laboratory stress SBP remained a significant predictor of LVMI, after controlling for BMI and clinic pressure.

CONCLUSIONS

These findings suggest that cardiovascular responses to behavioral stress are associated with individual differences in LVMI in men and women with high blood pressure who are overweight. Laboratory studies of behavioral stress may help promote our understanding of the pathophysiology of LVH.

Left ventricular mass index increases in proportion to the progression of diabetic nephropathy in Type 2 diabetic patients

The aim of our cross-sectional case-control study was to evaluate the mechanism of increased cardiac morbidity and mortality in Type 2 diabetic patients with normo-, micro-, and macroalbuminuria. Twenty-nine Type 2 diabetic patients with normoalbuminuria (group N), 19 patients with microalbuminuria (group M1), and seven patients with macroalbuminuria (group M2) were investigated. Groups were not significantly different concerning age, sex and diabetes duration. All patients took their normal medication throughout the study and had no clinical evidence of heart disease. Left ventricular mass index (LVMI) and systolic function were determined by echocardiography. As to the elevation of urinary albumin excretion levels, LVMI was significantly elevated, 101.4+/-20 gm(-2) of group N, 119.5+/-29 gm(-2) of group M1, and 141.9+/-27 gm(-2) of group M2. The prevalence of left ventricular hypertrophy (LVH) was significantly higher in group M2 (100%), and M1 (58%), as compared with group N (24%), but was not significantly different between groups M1 and M2. The body mass index and systolic blood pressure were significant independent predictors of LVMI by multiple regression analysis. In conclusion, the mechanism of the link between albuminuria and cardiovascular mortality was suggested to be LVH.

Use of ambulatory blood pressure monitoring data to predict left ventricular mass in hypertension

BACKGROUND

Many studies have shown definite but weak correlations between 24h blood pressure and left ventricular mass in hypertension.

OBJECTIVE

The present study applied an original multivariate analysis of parameters from ambulatory blood pressure monitoring to predict left ventricular mass in hypertension.

METHODS

Two hundred untreated hypertensive subjects (age=51+/-13 years, clinic blood pressure=163/98mmHg) had echocardiography and 24h recording of blood pressure. Data from 102 subjects were used to construct a mathematical model for prediction of left ventricular mass. The remaining 98 subjects were used to validate the model.

RESULTS

The model included age, weight, height, 24h systolic blood pressure, heart rate over 24h, standard deviations of systolic blood pressure and of heart rate over 24h. Using this model, we explained 63% of the variance of left ventricular mass. Moreover, the model was validated for the correlation (r=0.70) between measured and the estimated left ventricular mass.

CONCLUSIONS

Systolic blood pressure, heart rate and their standard deviations over 24h contribute to left ventricular mass in hypertensive subjects. Thus, it is important to take into account not only blood pressure but also heart rate in clinical studies.

Prognostic implications of left ventricular hypertrophy

BACKGROUND

To date there has been no comprehensive review of the association between left ventricular hypertrophy (LVH) at baseline and subsequent adverse clinical events.

METHODS

A total of 20 studies (with 48,545 participants) published between January 1960 and January 2000, identified through MEDLINE and other sources, related baseline electrocardiographic (ECG) or echocardiographic data on LVH to subsequent cardiovascular morbidity and all-cause mortality.

RESULTS

The prevalence of baseline LVH was higher in echocardiographic studies than in ECG studies (16%-74% vs 1%-44%, respectively). The adjusted risk of future cardiovascular morbidity associated with baseline LVH ranged from 1.5 to 3.5, with a weighted mean risk ratio of 2.3 for all studies combined. The adjusted risk of all-cause mortality associated with baseline LVH ranged from 1.5 to 8.0, with a weighted mean risk ratio of 2.5 for all studies combined. There was a trend toward a worse prognosis among women with baseline LVH compared with men. These findings persisted in the various population and ethnic groups studied.

CONCLUSION

With the exception of one study in dialysis patients, LVH consistently predicted high risk, independently of examined covariates, with no clear difference in relation to race, presence or absence of hypertension or coronary disease, or between clinical and epidemiologic samples. These results clarify the strong relation between LVH and adverse outcome and emphasize the clinical importance of its detection.

Effects of antihypertensive agents on the left ventricle: clinical implications

Hypertensive heart disease (HHD) is characterized by left ventricular hypertrophy (LVH), alterations of cardiac function, and coronary flow abnormalities. LVH is an independent cardiovascular risk factor related to cardiovascular complications in patients with hypertension. Therefore, a decrease in left ventricular mass is a therapeutic goal in these patients. The effect of the different antihypertensive agents on LVH regression has been studied in nearly 500 clinical trials. Most studies conclude that there is regression of LVH after significant decrease in blood pressure with most commonly prescribed antihypertensive agents. However, the ability to regress LVH is different between antihypertensive drug classes. ACE inhibitors and calcium channel antagonists are more potent in reducing left ventricular mass than beta-blockers, with diuretics falling in the intermediate group. Recent data suggest that angiotensin AT(1) receptor antagonists reduce left ventricular mass to a similar extent as ACE inibitors or calcium channel antagonists. Although a large number of studies have established that reversal of LVH decreases the occurrence of adverse cardiovascular events in patients with hypertension, the hypothesis that LVH regression is beneficial has not yet been conclusively proven. On the other hand, the time has come to revisit the current management of HHD simply focused on controlling blood pressure and reducing left ventricular mass. In fact, it is necessary to develop new approaches aimed to repair myocardial structure and protect myocardial perfusion and function and, in doing so, to reduce in a more effective manner, adverse risk associated with HHD. The identification of genes involved in both the process of HHD and the response to therapy may be critical for the development of these new approaches. This article will review briefly the available data on the effects of antihypertensive agents on HHD. In addition, the emerging new concepts on the pharmacology of hypertensive myocardial remodeling and the pharmacogenetic basis of the treatment of HHD will be also considered.

Left ventricular mass and atrial volume determined by cine magnetic resonance imaging in essential hypertension

To evaluate the relationship between left atrial volume determined by cine magnetic resonance imaging and progression of left ventricular hypertrophy (LVH), left atrial volume and echocardiographic left ventricular mass (LVM) were measured in 30 hypertensive patients (15 without LVH and 15 with LVH) and 10 normotensive control subjects. We also evaluated the effects of antihypertensive therapy on the cardiac chamber volumes and LVM in hypertensive patients. The cardiac chamber volumes and LVM were indexed by body surface area. Although there were no significant differences in left ventricular chamber volumes among the three groups, both maximum and minimum left atrial volume indexes, and the LVM index were greater in hypertensive patients with LVH than in the other two groups. The LVM index was correlated with maximum left atrial volume index (r = 0.74, P < .0001), and minimum left atrial volume index (r = 0.76, P < .0001), respectively. Furthermore, in multivariate models, the LVM index was significantly correlated with maximum left atrial volume index. In hypertensive patients with LVH, both maximum and minimum left atrial volume indexes, and the LVM index significantly reduced after treatment. The percent of changes in maximum left atrial volume index after treatment was significantly correlated with the percent of changes in LVM index after treatment. In conclusion, our data indicate that LVH is an independent determinant of left atrial enlargement, and both LVH and left atrial enlargement may be reversed by some effective therapeutic interventions.

Ambulatory blood pressure monitoring and echocardiography--noninvasive techniques for evaluation of the hypertensive patient

Clinic blood pressure measurements have only limited ability to determine which hypertensive patients are at greatest risk of cardiovascular events. Ambulatory blood pressure monitoring allows for noninvasive measurement of blood pressure throughout the 24-hour period. This may help to clarify discrepancies between blood pressure values obtained in and out of the clinic and confirm the presence of white-coat hypertension, broadly defined as an elevated clinic blood pressure but a normal ambulatory blood pressure. Ambulatory blood pressure values have been shown to have a better relationship to cardiovascular morbidity and mortality and end-organ damage than clinic blood pressure values. Further, patients with white-coat hypertension appear to be at greater risk of cardiovascular morbidity and end-organ damage than a normotensive population, although they are at less overall risk than a hypertensive population. Hypertensive heart disease is characterized by diastolic dysfunction, increased left ventricular mass, and coronary flow abnormalities. Left ventricular hypertrophy increases the risk of coronary heart disease, congestive heart failure, stroke, ventricular arrhythmias, and sudden death. A variety of invasive and noninvasive techniques are described herein that measure left ventricular mass, diastolic function, and coronary blood flow abnormalities. Most antihypertensive treatments promote regression of left ventricular hypertrophy and reversal of diastolic dysfunction, which may decrease symptoms of congestive heart failure and improve survival.

The heart and conduit vessels in hypertension

The heart and conduit vessels, integral components of a pulsatile pumping system, undergo complex adaptive and degenerative changes in response to the increased load of hypertension. Over the last two decades, great technological strides have been made with regards to further discovering the role of the heart and conduit vessels in hypertension. This article reviews the adaptation of the heart and vessels to hypertension, the clinical implications of these structural and functional changes, and the effects of therapy on cardiovascular function.

Cerebrovascular reactivity in hypertensive patients: a transcranial Doppler study

PURPOSE

We studied the usefulness of transcranial Doppler sonography for assessing changes in vasoreactivity in patients with hypertension and the hemodynamic consequences of hypertension.

METHODS

The study group comprised 25 patients with chronic severe hypertension and 25 age- and sex-matched healthy subjects. Cerebrovascular reserve capacity was assessed by transcranial Doppler recording of the blood flow velocity in both middle cerebral arteries before and 5, 10, 15, and 20 minutes after intravenous injection of 1 g of acetazolamide (Diamox). Blood pressure, blood gases, and other blood parameters were also measured before and after acetazolamide injection. The sizes of the left atrium, left ventricle, and aortic root were measured by echocardiography and correlated with the vasoreactivity after acetazolamide injection.

RESULTS

After acetazolamide injection, no significant changes in blood pressure were observed in either group. The mean blood flow velocity in the middle cerebral arteries of hypertensive patients (60.8 +/- 2.6 cm/sec) was not significantly different from that of controls (58.8 +/- 1.9 cm/sec) before acetazolamide injection. Ten minutes after acetazolamide injection, the percentage change in blood flow velocity was significantly lower in the hypertensive group (36.2 +/- 4.5%) than in the controls (52.6 +/- 3.7%). A significant negative correlation (p < 0.05) between decreased vasoreactivity and increased size of the left atrium and aortic root was observed.

CONCLUSIONS

Vasoreactivity decreases in hypertensive patients without neurologic deficits or computed tomography abnormalities. Enlargement of the left atrium correlates well with the severity of the impairment in vasoreactivity. Transcranial Doppler sonography can be a sensitive tool in the investigation of vascular impairment caused by hypertension and in the follow-up of hypertensive patients.

Myocardial glucose metabolism is different between hypertrophic cardiomyopathy and hypertensive heart disease associated with asymmetrical septal hypertrophy

Myocardial glucose metabolism has been shown to be heterogeneous in patients with hypertrophic cardiomyopathy (HCM). We tested the hypothesis that myocardial glucose metabolism differs between patients with HCM and those with hypertensive heart disease (HHD) associated with asymmetrical septal hypertrophy. We studied 12 patients with HCM, 7 HHD patients associated with asymmetrical septal hypertrophy using 18F 2-deoxyglucose (FDG) and positron emission tomography. We calculated % FDG fractional uptake in the inter-ventricular septum and posterolateral wall. Heterogeneity of FDG uptake was evaluated by % interregional coefficient of variation of FDG fractional uptake in each wall segment. In both the interventricular septum and posterolateral wall, % FDG fractional uptake was not significantly different between the two groups. The % interregional coefficient of variation for both interventricular septum (10.6 +/- 1.6 vs. 4.1 +/- 0.5, p < 0.01) and posterolateral wall (5.9 +/- 0.7 vs. 3.8 +/- 0.5, p < 0.05) was significantly larger in patients with HCM than in HHD patients associated with asymmetrical septal hypertrophy. Echocardiography demonstrated that the degree of asymmetrical septal hypertrophy was similar between the two groups. These results suggest that myocardial glucose metabolism may be more heterogeneous in patients with HCM compared to HHD patients associated with asymmetrical septal hypertrophy, although the left ventricular shape is similar. The difference in the heterogeneity might have resulted from differences in the pathogeneses of the two diseases.

Left atrial size in hypertensive men: influence of obesity, race and age. Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

OBJECTIVES

We sought to determine the relations of left atrial (LA) size to blood pressure, obesity, race, age and left ventricular (LV) mass in hypertension.

BACKGROUND

Although obesity, race and age may influence LV mass, their effects on LA size have not been defined in hypertension.

METHODS

Left atrial size was measured in 690 men (58% African-Americans) with mild to moderate hypertension (mean [+/-SD] blood pressure 152 +/- 15/98 +/- 6 mm Hg) and a high prevalence of LV hypertrophy. Effects of LV mass, adiposity, race, age, physical activity, height, weight, sodium excretion, plasma renin activity and heart rate were examined.

RESULTS

Left atrial size was greater (p < or = 0.0001) in obese (44.2 +/- 5.7 mm) than in overweight (41.6 +/- 5.9 mm) or normal weight (38.9 +/- 6.2 mm) patients. Left atrial enlargement (> or = 43 mm) was present in 56% of obese patients compared with 42% of overweight and 25% of normal weight hypertensive men. As age increased, white patients had a greater LA size than African-American patients. Although there was no relation between LV mass and LA size in normal weight patients, there was a significant positive relation in obese patients. On multiple regression analysis, obesity was the strongest independent predictor of increased LA size.

CONCLUSIONS

Obesity is the strongest predictor of LA size in patients with hypertension and amplifies the relation between LA size and LV mass. Race influences effects of age and hypertension on LA size. Because increased LA size and LV mass (also influenced by obesity) are associated with an adverse outcome, these findings underscore the importance of obesity, race and age with regard to the cardiac effects of hypertension.

Mechanism of left atrial enlargement related to ventricular diastolic impairment in hypertension

BACKGROUND AND HYPOTHESIS

Systemic hypertension is the leading cause of left ventricular (LV) hypertrophy. The present study aimed to investigate the mechanism of left atrial (LA) enlargement in patients with hypertensive heart disease during cardiac catheterization.

METHODS

Data were obtained from eight control subjects and seven patients with hypertensive heart disease. Left atrial and LV pressures from catheter-tip micromanometer, and LA and LV volumes from biplane cineangiograms were analyzed during the same cardiac cycle.

RESULTS

Left atrial maximal volume were 93 +/- 26 ml in patients with hypertensive heart disease and 63 +/- 12 ml in control subjects (p < 0.05). In patients with hypertensive heart disease, time constant of LV relaxation was significantly greater than that in controls (54 +/- 18 vs. 31 +/- 16 ms, respectively; p < 0.01). Left atrial maximal volume correlated with time constant of LV relaxation (r = 0.86, p < 0.01). The ratio of LV filling volume before LA contraction to LV stroke volume in patients with hypertensive heart disease was significantly lower than that in control subjects (65 +/- 13 vs. 76 +/- 7%, respectively; p < 0.05). On the other hand, the ratio of LV filling volume during LA contraction to stroke volume in patients with hypertensive heart disease was significantly higher than that in controls (35 +/- 13 vs. 24 +/- 7%, respectively; p < 0.05). Left atrial volume before LA contraction in patients with hypertensive heart disease was significantly larger than that in controls (74 +/- 22 vs. 47 +/- 10 ml, respectively, p < 0.01). During LA contraction, LA work was significantly increased in patients with hypertensive heart disease compared with that in controls (274 +/- 101 vs. 94 +/- 42 mmHg. ml, respectively; p < 0.001). Left atrial work showed significant correlation with LA volume before LA contraction (r = 0.75, p < 0.01).

CONCLUSION

Left ventricular diastolic filling was impaired in patients with hypertensive heart disease. Enlargement of left atrium might be attributed to the impairment of blood flow from left atrium to left ventricle due to the increased LV stiffness.

Ambulatory blood pressure and echocardiographic left ventricular dimensions in elderly hypertensive subjects

In a consecutive series of 62 hypertensive elderly subjects, the authors studied the relation of blood pressure circadian variations with echocardiographic parameters of left ventricular (LV) hypertrophy. All the subjects were submitted to an ambulatory blood pressure monitoring (ABPM) and to B- and M-mode echocardiography. In the elderly hypertensive group, LV mass index (LVMI) was more strongly related to twenty-four-hour, daytime and nighttime systolic ambulatory blood pressure (r = 0.52, r = 0.37, r = 0.51) than diastolic ambulatory blood pressures were (r = 0.32, r = 0.18, r = 0.33). Casual systolic and diastolic blood pressure (CBP) was found more weakly related to LVMI than ambulatory blood pressures were (r = 0.35, r = 0.26). Elderly hypertensive subjects were divided into two subgroups in relation to the presence (group 1) or absence (group 2) of blood pressure nocturnal decline. No differences were found between these two subgroups in regard to: casual blood pressure values, ambulatory blood pressures in the diurnal period, sex, body surface area, height, weight, and age. LVMIs were computed in all three groups and showed the following results: 89.32 +/- 19.76 in elderly normotensives, 91.21 +/- 31.32 in group 1, and 99.80 +/- 18.21 in group 2. Echocardiographic parameters of LV dimensions and LVMIs were different in group 1 and 2. An inverse correlation, statistically significant, was observed between LVMIs and the nocturnal blood pressure reduction (systolic: r = -0.36, P < 0.05; diastolic: r = -0.29, P < 0.05). These results suggest an association between a smaller LV mass and nocturnal blood pressure decline in elderly hypertensive patients.

Clinical implications of white coat hypertension

OBJECTIVE

To determine the clinical implications of mild white coat hypertension (WCH).

SUBJECTS AND METHODS

We studied 102 subjects (54 men, 48 women), 51 of whom were normotensive and 51 slightly hypertensive. None had ever received antihypertensive therapy. An ambulatory blood pressure (ABP) record (Accutracker II), a 24-h electrocardiogram and an echocardiogram were obtained from each, and each was examined by funduscopy. WCH subjects were compared with sustained hypertension (SH) subjects and with normotensives.

RESULTS

Fifty-three percent of the hypertensives qualified as WCH. The ultrasonographic characteristics and the ABP variables of the WCH group differed significantly from those of normotensives, but not from those of the SH group. The prevalence of left ventricilar hypertrophy (LVH) in the SH group (62.5%) did not differ significantly from its prevalence in the WCH group (40.7%), but the prevalence among normotensives (17.6%) was significantly lower than in either of the other two groups. The WCH and SH groups did not differ significantly as regards the prevalence of hypertensive retinopathy (33.3% in the former, 58.3% in the latter). For no non-LVH, non-retinopathic subject, whether normotensive or hypertensive, were more than 18% of daytime diastolic ABP measurements > or = 90 mmHg. Ultrasonographic findings were no better correlated with ABP than with in-clinic BP measurements. Fundus findings correlated well with in-clinic BP and with numerous ABP parameters. Retinopathy, with or without LVH, was efficiently predictable among hypertensives on the basis of body mass index and the 24-h maximum of systolic BP.

CONCLUSIONS

Myocardiac remodelling and vascular retinopathy develop early and in parallel in hypertensives, and both developments appear to involve determinants including body mass index and 24-h maximum systolic BP. WCH subjects, as defined by current ABP-based criteria, have cardiac and retinovascular characteristics different to normotensive subjects. Stricter criteria are needed to discriminate between hypertensives with and without the systemic developments that constitute the immediate source of risk to the hypertensives individual.