Relation between left ventricular geometric alteration and extracardiac target organ damage in hypertensive patients

Left Ventricular Hypertrophy Is More Prevalent in Type B than Type A Aortic Dissection

OBJECTIVES

Several factors determining differences between types A and B aortic dissection (AD) have been reported; however, little data exist examining their differences in left ventricular hypertrophy (LVH). We compared the prevalence of LVH in patients with types A and B AD.

METHODS

We retrospectively analyzed 334 patients with acute AD (227 type A; 107 type B). Concentric hypertrophy (CH; increased left ventricular mass index [LVMI] and relative wall thickness [RWT]) is one of four types of left ventricular (LV) geometry thought to be most associated with hypertension. We compared LVMI and the prevalence of CH in patients with types A or B AD. Multivariate logistic regression analyses of variables associated with type B AD were performed.

RESULTS

Comparing type A and B AD, LVMI (95 ± 26 vs.107 ± 28, p <0.001) and prevalence of CH (26% vs. 44%, p = 0.001) were higher in type B AD. In multivariate analysis, CH was an independent factor associated with type B AD (odds ratio: 2.62, confidence interval: 1.54-4.47, p <0.001).

CONCLUSIONS

Our data suggested LVH was more prevalent in type B than in type A AD. Considering LVH usually results from hypertension, patients with type B AD may be more affected by hypertension than those with type A.

Wave Intensity Analysis Can Identify Eccentric Cardiac Hypertrophy in Hypertensive Patients With Varied Left Ventricular Configurations

OBJECTIVES

The primary aim of this study was to determine whether wave intensity can discriminate cases of eccentric hypertrophy in patients with essential hypertension who have varied left ventricular configurations.

METHODS

A total of 155 hypertensive patients with different ventricular configurations (27 normal configuration, 42 concentric remodeling, 62 concentric hypertrophy, and 24 eccentric hypertrophy) were recruited. We performed a noninvasive wave intensity analysis of the common carotid artery and conventional echocardiography. Blood pressure and flow velocity were measured in the right carotid artery of all patients.

RESULTS

The left ventricular ejection fraction (LVEF) in the eccentric hypertrophy group was significantly lower than the values in the other groups (P < .05). The R-W1 interval/W1-W2 interval ratio (where W1 indicates the first positive peak and W2 the second positive peak) in the eccentric hypertrophy group was much higher than the values in the other groups (P < .05). However, there were no significant differences in W1, W2, and negative area among these groups. Pearson correlation analysis showed that R-W1/W1-W2, R-W1, and W1-W2were correlated with the LVEF, whereas there was no correlation between W1, W2, negative area, and the reflection coefficient with the LVEF.

CONCLUSIONS

We propose that by using the R-W1/W1-W2 ratio, wave intensity analysis can identify hypertensive patients with eccentric hypertrophy without the need for echocardiography.

Midwall mechanics in physiologic and hypertensive concentric hypertrophy

OBJECTIVE

We sought to analyze and compare midwall fractional shortening (mFS), and its relations with circumferential end-systolic stress (cESS) and relative wall thickness (RWT), among subjects with physiologic concentric left ventricular (LV) hypertrophy, patients with hypertension and concentric LV hypertrophy, and control subjects.

METHODS

A total of 51 normotensive athletes and 56 young patients with hypertension and echocardiographic evidence of concentric LV hypertrophy were enrolled. In addition, 49 age- and sex-matched control subjects were recruited. LV cavity size and wall thicknesses, LV mass, RWT, cESS, and mFS were determined by echocardiography.

RESULTS

The 3 groups were similar in age, sex, height, weight, body surface area, LV diameters, and conventional indices of systolic function. LV thicknesses, RWT, LV mass, and LV mass index were similarly increased in the athletes and in the hypertensive group when compared with the control subjects. A similar depression in mFS was observed in both the athletes (22.4 +/- 2.6%) and hypertensive group (22.5 +/- 3.6%) in comparison with the control group (24.5 +/- 2.5%, P =.0003). The depression in mFS was still significant after taking into account the effect of cESS, but was no more evident after indexation of mFS by RWT or LV mass. At regression analysis, the relation between mFS and cESS showed a steeper negative slope in the patients with hypertension than in the other 2 groups.

CONCLUSIONS

MFS is similarly depressed in physiologic and hypertensive concentric LV hypertrophy. The depression is abolished by adjustment for RWT or LV mass, suggesting that geometric factors are the major determinants of midwall performance in both types of concentric LV hypertrophy. However, an impaired response to different values of cESS seems to exist only in hypertensive concentric LV hypertrophy, because increasing levels of cESS may be associated with more evident mFS depression in patients with hypertension than in the athletes and control subjects.

The relation between left ventricular geometric patterns and left ventricular midwall mechanics in hypertensive patients

To evaluate the alteration of myocardial contractility in hypertensive patients with different left ventricular geometric patterns by the end-systolic stress-midwall fractional shortening relation. Echocardiography was applied to study the left ventricular geometry and cardiac function among 117 cases of essential hypertension, with 45 normal cases as control(s). Left ventricular mass index (LVMI) and relative wall thickness (RWT) were calculated using echocardiographic data. All patients were divided into four kinds of left ventricular geometry pattern based on LVMI and RWT. Patients of the eccentric hypertrophy group suffered the most serious damage of left ventricular systolic function. Myocardial contractility shown by end-systolic stress-midwall fractional shortening relation was significantly decreased in the concentric remodeling group, eccentric hypertrophy group and concentric hypertrophy group, and those with concentric hypertrophy showed the worst contractility. The degree of myocardial contractility damage was different in patients with different left ventricular geometric patterns. Geometric changes may have compensated for the reduction of myocardial contractility in some phases in order to maintain the normal pump function.