Early signs of cardiac involvement in hypertension

The HARVEST. Looking for optimal management of young people with stage 1 hypertension

In the last few decades there has been much debate about the management of low-risk stage 1 hypertension in youth. In this article, we review the main findings of the HARVEST cohort accrued over 30 years, highlighting the contribution of this study to the existing literature. Tachycardia and sympathetic overdrive were closely intertwined in our HARVEST participants, promoting the development of sustained hypertension, metabolic abnormalities, and increased susceptibility to vascular complications. Short-term blood pressure variability in this age group had a prognostic power even greater than that of average 24h blood pressure. In the HARVEST participants, changes in left ventricular anatomy and contractility were the earliest signs of hypertensive cardiac involvement, whereas left ventricular filling was only marginally affected. Our results highlighted the role of glomerular hyperfiltration in determining microalbuminuria and renal damage in the early stage of hypertension. The genetic approach provided an important contribution to risk stratification and patient management. The HARVEST confirmed the importance of maintaining a good lifestyle for preventing the onset of hypertension, diabetes and cardiovascular events. Isolated systolic hypertension in the first decades of life appeared as a heterogeneous condition. To establish whether antihypertensive drug treatment should be started in this condition the clinician should consider the individual cardiovascular risk profile, the level of office mean BP and central BP. Despite recent progress in our knowledge, systolic hypertension still represents a challenging issue for the clinician. Hopefully, the HARVEST will continue to contribute data that help to fill the present gaps in evidence.

Cardiovascular sexual dimorphism in a diet-induced type 2 diabetes rodent model, the Nile rat (Arvicanthis niloticus)

Background

The Nile rat (Arvicanthis niloticus) is an emerging laboratory model of type 2 diabetes. When fed standard rodent chow, the majority of males progress from hyperinsulinemia by 2 months to hyperglycemia by 6 months, while most females remain at the hyperinsulinemia-only stage (prediabetic) from 2 months onward. Since diabetic cardiomyopathy is the major cause of type-2 diabetes mellitus (T2DM)-related mortality, we examined whether sexual dimorphism might entail cardiac functional changes. Our ultimate goal was to isolate the effect of diet as a modifiable lifestyle factor.

Materials and methods

Nile rats were fed either standard rodent chow (Chow group) or a high-fiber diet previously established to prevent type 2 diabetes (Fiber group). Cardiac function was determined with echocardiography at 12 months of age. To isolate the effect of diet alone, only the small subset of animals resistant to both hyperinsulinemia and hyperglycemia were included in this study.

Results

In males, Chow (compared to Fiber) was associated with elevated heart rate and mitral E/A velocity ratio, and with lower e’-wave velocity, isovolumetric relaxation time, and ejection time. Of note, these clinically atypical types of diastolic dysfunction occurred independently of body weight. In contrast, females did not exhibit changes in cardiovascular function between diets.

Conclusions

The higher prevalence of T2DM in males correlates with their susceptibility to develop subtle diastolic cardiac dysfunction when fed a Western style diet (throughout most of their lifespan) despite no systemic evidence of metabolic syndrome, let alone T2DM.

A comparison study of the echocardiographic changes in hypertensive patients treated with telmisartan vs. enalapril

BACKGROUND

Hypertension-induced cardiac dysfunction is variable among different anti-hypertensive medications. This study compares the effects of telmisartan and enalapril on echocardiographic parameters in hypertensive patients.

MATERIALS AND METHODS

This was a randomised single blinded study. Eighty hypertensive patients were included in this study and they were randomly allocated into two study groups: Group 1 included 40 patients who took telmisartan 80mg once daily for six months. Group 2 included 40 patients who took enalapril, 20mg once daily for six months. An additional 40 healthy participants were enrolled in the study as controls (Group 3). Baseline echocardiographic scan was done at the start of the study and after 6 months of treatment including assessment of left ventricular systolic and diastolic functions with assessment of left ventricular mass index, in addition to measurements of blood pressure, heart rate and double product.

RESULTS

Both group 1 and group 2 (telmisartan and enalapril groups respectively) showed comparable statistically significant improvement in the diastolic functional parameters (P<0.010), while both medications didn't demonstrate changes in the systolic functional parameters. Furthermore, telmisartan was significantly effective in reducing the interventricular septal thickness and left ventricular mass index (P<0.010).

CONCLUSIONS

Both drugs interfere with renin-angiotensin aldosterone system, protecting the myocardium from high blood pressure. Findings from our study provide key results for physicians in deciding the appropriate antihypertensive drug for each patient depending based on the patient's intolerability for either medication.

Echocardiographic Assessment of Left Ventricular Structure in Hypertension and the Impact on Clinical Outcomes

Hypertension (HTN) is present in nearly 50 million individuals, or approximately 29% of the adult US population. The prevalence of HTN is higher in men, increases with age, and varies among ethnic groups. Alterations of left ventricular structure and function can be present in patients with HTN and accurately characterized by echocardiography. The presence of left ventricular hypertrophy with increased left ventricular mass has prognostic implications in patients with HTN.

Structural and functional left ventricular impairment in subjects with chronic spinal cord injury and no overt cardiovascular disease

CONTEXT

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in subjects with long-term spinal cord injury (SCI). More specific recommendations for CVD prevention in this population are needed.

METHODS

One hundred thirty male subjects (47 subjects with SCI and 83 able-bodied persons (ABPs), mean age 43.89 ± 1.9 and 45.44 ± 12.2 years; P = 0.48) underwent transthoracic echocardiography (TTE). The effects of age, weight, mean arterial pressure (MAP) and level of physical training on cardiac adaptations were evaluated through multiple regression analysis.

RESULTS

In subjects with SCI, TTE revealed increased wall thickness (P < 0.05), lower E wave, E/A ratio and early diastolic myocardial relaxation velocity on Tissue Doppler Imaging (TDI) (P < 0.05) and higher systolic myocardial contraction velocity on TDI (0.10 ± 0.02 vs. 0.09 ± 0.02 m/seconds, P = 0.002) and peak systolic pressure to end-systolic volume ratio (3.62 ± 1.39 vs. 2.82 ± 0.90, P < 0.001) compared with ABPs. Aortic diameters were larger in subjects with SCI than ABPs. Differences remained statistically significant even after adjustment for age, weight, MAP, and level of physical training. Weight and age were found to be independent variables that substantially affected left ventricular structure and function in subjects with SCI.

CONCLUSIONS

Subjects with post-traumatic chronic SCI and no overt cardiovascular risk factors, exhibit initial left ventricular remodeling (as assessed by TTE) compared with ABPs. Lifestyle modifications, including regular physical exercise and weight control, should be implemented in all subjects with SCI, even at a very early stage, in order to reduce cardiovascular risk and prevent the development of CVD.

White-coat hypertension in the elderly. Echocardiographic analysis. A substudy of the EPICARDIAN project

The aims of this study were to investigate echocardiographic abnormalities in the elderly and to evaluate differences between those who are normotensive and those who have white-coat hypertension or sustained hypertension. The study used data on a subsample of participants in the EPICARDIAN project who came from the Lista district of Madrid, Spain. Of the 271 included, 61 (22.5%) were normotensive, 81 (29.9%) had white-coat hypertension and 129 (49.6%) had sustained hypertension. The left ventricular mass index was significantly different between the subgroups: 94.9 g/m2 in normotensives, 125.6 g/m2 in those with white-coat hypertension and 136.3 g/m2 in those with sustained hypertension (P< .001). The prevalence of left ventricular hypertrophy, defined using Deveraux's criteria, was 13.2% in normotensives, 49.1% in those with white-coat hypertension and 54.3% in those with sustained hypertension (P=.00007). White-coat hypertension is not a innocuous finding in the elderly because its implications for cardiac health are closer to those of sustained hypertension than to those of normal blood pressure.

Echocardiographic and spiroergometric data of elite Hungarian female water polo players

In the authors' earlier study the relative aerobic power of Hungarian top-level male water polo players was found to be smaller than that of other top-level athletes, while their echocardiographic parameters proved to be the most characteristic of the athlete's heart. In the present investigation echocardiographic and spiroergometric data of female top-level water polo players were compared to those of other female elite athletes and of healthy, non-athletic subjects. Relative aerobic power in the water polo players was lower than in endurance athletes. Mean resting heart rates were the slowest in the water polo players and endurance athletes. Morphologic indicators of the heart (body size related left ventricular wall thickness and muscle mass) were the highest in the water polo players, endurance and power athletes. In respect of diastolic functions (diastolic early and late peak transmitral flow velocities) no difference was seen between the respective groups.These results indicate that, similarly to the males, top-level water polo training is associated with the dimensional parameters of the heart rather than with relative aerobic power. For checking the physical condition of female water polo players spiroergometric tests seem to be less appropriate than swim-tests with heart rate recovery studies such as the ones used in the males.

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 ventricle diastolic dysfunction in obese patients with newly diagnosed arterial hypertension

BACKGROUND

The frequent coexistence of obesity and arterial hypertension is well known. Although both conditions have been identified as independent risk factors for impaired left ventricular diastolic function, there is a paucity of data on the dysfunction among obese patients with newly diagnosed arterial hypertension. The study was performed to determine the prevalence of diastolic dysfunction in obese individuals with newly diagnosed arterial hypertension and to compare it with the prevalence in normotensive obese persons.

METHODS

We enrolled 125 obese patients: 65 with newly diagnosed hypertension and 60 normotensive patients matched for age, sex and body mass index. Left ventricular diastolic function was assessed from the following Doppler-echocardiographic measurements: mitral inflow velocities (E and A wave), E wave deceleration time, isovolumetric relaxation time, left atrial and left ventricular diameters, left ventricular wall thickness and left ventricular heart mass index. Diastolic dysfunction was considered when the E/A ratio was <1.

RESULTS

We found significantly higher A wave, lower E/A ratio, longer E deceleration time and a bigger left atrium in obese patients with newly diagnosed arterial hypertension. We did not find significant differences in E wave peak velocities between the two groups. Although there was no difference in left ventricle heart mass or the prevalence of left ventricle hypertrophy, the prevalence of diastolic dysfunction was higher in the group with newly diagnosed arterial hypertension.

CONCLUSION

This study suggests that newly diagnosed arterial hypertension significantly contributes to impairment of left ventricular diastolic function in obese patients before development of structural aberrations detectable on echocardiography.

Cardiac and systemic hemodynamic characteristics of hypertension and prehypertension in adolescents and young adults: the Strong Heart Study

BACKGROUND

The epidemic of overweight is increasing the prevalence of both prehypertension and early-onset hypertension, but few population-based data exist on their impact on cardiac structure and function in adolescents and young adults.

METHODS AND RESULTS

We analyzed clinical characteristics, hemodynamic parameters, and left ventricular structure and function in 1940 participants, 14 to 39 years of age, in the Strong Heart Study. Hypertension occurred in 294 participants (15%), who were more often men (70% versus 30%), older (age, 31+/-7 versus 25+/-8 years), and more commonly diabetic (23% versus 4.5%; all P<0.001) than their normotensive counterparts. Prehypertension occurred in 675 (35%) of participants with similar trends in gender, age, and diabetes status. After adjustment for covariates, both hypertensive and prehypertensive participants had higher left ventricular wall thickness (0.83 and 0.78 versus 0.72 cm), left ventricular mass (182 and 161 versus 137 g), and relative wall thickness (0.30 and 0.29 versus 0.28 cm) and 3- and 2-fold-higher prevalences of left ventricular hypertrophy than their normotensive counterparts (all P<0.001). Hypertension and prehypertension also were associated with higher mean pulse pressure/stroke volume index (1.24 and 1.15 versus 1.02 mm Hg/mL x m2) and total peripheral resistance index (3027 and 2805 versus 2566 dynes x s x cm(-5) x m2; all P<0.001).

CONCLUSIONS

In a population with high prevalences of obesity and diabetes, hypertension and prehypertension are associated with increases in both cardiac output and peripheral resistance index. Despite the young age of participants with hypertension and prehypertension, they had prognostically adverse preclinical cardiovascular disease, including left ventricular hypertrophy and evidence of increased arterial stiffness.

Left ventricular geometry in patients with obstructive sleep apnea coexisting with treated systemic hypertension

BACKGROUND

Left ventricular (LV) hypertrophy is a common consequence of systemic hypertension (SH) and obstructive sleep apnea (OSA). However, little is known about the degree of LV involvement in patients with OSA coexisting with treated SH.

OBJECTIVES

Our study was designed in order to assess the prevalence of distinct types of LV geometry in treated hypertensive OSA patients.

METHODS

PATIENTS

183 patients with treated SH were enrolled to the study. Group 1 consisted of 38 patients with newly-diagnosed OSA and ineffectively treated SH. The remaining 145 patients with effectively treated SH were divided into three groups: group 2 - 70 patients with newly-diagnosed OSA, group 3 - 31 patients with OSA treated with continuous positive airway pressure (CPAP), and group 4 - 44 patients without OSA. Overnight sleep studies and M-mode echocardiography were performed.

RESULTS

LV mass index did not differ between the study groups. Mean values of LV end-diastolic diameter (LVED) were 55.4 +/- 6.8 mm in group 1 and 53.6 +/- 6.9 mm in group 2 and were significantly increased in comparison to subjects treated with CPAP and controls (49.8 +/- 6.8 mm and 50.1 +/- 64.7 mm, respectively; p = 0.001). LVED correlated positively with the apnea-hypopnea index and desaturation index. LV eccentric hypertrophy was the commonest type of LV geometry in newly-diagnosed OSA patients.

CONCLUSIONS

The major finding of our study is the predominance of LV eccentric hypertrophy in newly-diagnosed OSA patients. We suggest that a relatively moderate degree of LV involvement in hypertensive OSA patients may depend on the cardioprotective effect of concomitant antihypertensive therapy, ameliorating OSA-dependent neurohumoral abnormalities.

Prevalence and Clinical Significance of Isolated Ambulatory Hypertension in Young Subjects Screened for Stage 1 Hypertension

Little is known about the clinical significance of isolated ambulatory hypertension, a condition characterized by low office but elevated ambulatory blood pressure. This study aimed to investigate the prevalence and the predictive value of isolated ambulatory hypertension diagnosed after 3 months of observation for the development of sustained hypertension within a cohort of 871 never-treated stage-1 hypertensive subjects. The study end point was progression to more severe hypertension and need of antihypertensive medication. In 244 subjects (28%), clinic blood pressure declined to <140/90 mm Hg after 3 months. Of these, 124 (14.2% of total) had low clinic and ambulatory blood pressures after 3 months (nonhypertensive subjects), whereas 120 subjects (13.8% of total) showed low clinic but elevated ambulatory blood pressure (isolated ambulatory hypertension). During the 6 years of observation, the number of end points based on multiple clinic blood pressure readings progressively increased from the nonhypertensive subjects (19%) to the subjects with isolated ambulatory hypertension (35%) and to the subjects with high clinic and high ambulatory blood pressures (65%, P<0.0001). In an adjusted proportional hazard model, isolated ambulatory hypertension status was associated with a 2.2 (P=0.02) increase in the risk of reaching the end point in comparison with the nonhypertensive subjects. Final ambulatory systolic blood pressure was also higher in the former than the latter (P=0.03). Our results indicate that among subjects screened for stage 1 hypertension, individuals with isolated ambulatory hypertension after 3 months of observation have increased risk of developing sustained hypertension in later life compared with subjects in whom both clinic and ambulatory blood pressures are normal.