Left ventricular hypertrophy in patients with autonomic failure.

BACKGROUND: In autonomic failure (AF), supine hypertension may predispose patients to end-organ damage. The pathophysiology of hypertensive heart disease in AF is not known. The aim of the present study was to evaluate the prevalence and predisposing factors of left ventricular hypertrophy (LVH) in patients with AF. METHODS: We studied 25 patients with AF (67 +/- 8 years); 80% were being treated for orthostatic hypotension. Twenty patients with essential hypertension (68 +/- 6 years) were considered as the control group. All subjects underwent echocardiography for measurement of left ventricular mass (LVM). The patients with AF underwent a 24-h BP monitoring and long-term blood pressure (BP) variability was calculated as standard deviation (SD) of the average of the half-hour mean values. RESULTS: The LVM is comparable in patients with AF and hypertensive controls (145 +/- 35 g/m2 v 127 +/- 32 g/m2, P = .07). The proportion of patients with LVH is similar in both populations (AF 80%, hypertensive 70%). The patients with AF were divided into two groups, with and without LVH. The SDs are significantly higher in AF patients with LVH than in those with normal LVM (SD 24-h systolic BP: 22 +/- 4 v 14 +/- 1 mm Hg, P = .001). CONCLUSIONS: A high proportion of patients with AF show LVH. The LVM values are comparable with those of patients with essential hypertension. The development of LVH seems to depend on high BP variability, characteristic of AF patients. Detection of LVH may help in the choice of treatment for orthostatic hypotension and in the prevention of heart failure.

Comparison between generalized retinal arteriolar narrowing and left ventricular mass in young untreated hypertensive patients.

PURPOSE: This study aims to examine the relationship between retinal arteriolar narrowing and left ventricular hypertrophy in hypertensive patients. METHODS: A total of 30 patients with a recent history of hypertension (22 M, 8 F; 33 +/- 8; BMI 24,96 +/- 2.8;), consecutively referred to the Hypertension Unit by their family doctors, were studied. Generalized retinal arteriolar narrowing was measured by two ophthalmologists from computer-scanned images on retinal photographs, and summarized as arteriole-to-venule ratio (AVR). Left ventricular hypertrophy was evaluated by quantitative M-mode echocardiography. RESULTS: All patients were stratified according to the 2003 European Society of Hypertension (ESH) guidelines: 20 subjects (66.7%) were affected by hypertension grade 1, and 10 (33.3%) were affected by hypertension grade 2. Retinal vessel diameters did not differ significantly by grade 1 vs grade 2 hypertension. Echocardiographic left ventricular hypertrophy was present in 10 (33%) patients. No significant correlation was shown between arteriole-to-venule ratio (AVR) and left ventricular mass. [Spearman r = 0.22; p = 0.23]. CONCLUSIONS: We suggest some explanations for the fact that we did not find any correlation between AVR and left ventricular mass. Further clinical studies are required for a greater understanding as to whether early microvascular changes relate with other clinical indicators of hypertensive organ damage.

Assessment of cardiac autonomic modulation during adolescent obesity.

OBJECTIVE: To investigate the cardiovascular autonomic function in pediatric obesity of different duration by using standard time domain, spectral heart rate variability (HRV), and nonlinear methods. RESEARCH METHODS AND PROCEDURES: Fifty obese children (13.9 +/- 1.7 years) were compared with 12 lean subjects (12.9 +/- 1.6 years). Obese children were classified as recent obese (ROB) (<4 years), intermediate obese (IOB) (4 to 7 years), and long-term obese (OB) (>7 years). In all participants, we performed blood pressure (BP) measurements, laboratory tests, and 24-hour electrocardiogram/ambulatory BP monitoring. The spectral power was quantified in total power, very low-frequency (LF) power, high-frequency (HF) power, and LF to HF ratio. Total, long-term, and short-term time domain HRV were calculated. Poincaré plot and quadrant methods were used as nonlinear techniques. RESULTS: All obese groups had higher casual and ambulatory BP and higher glucose, homeostasis model assessment, and triglyceride levels. All parameters reflecting parasympathetic tone (HF band, root mean square successive difference, proportion of successive normal-to-normal intervals, and scatterplot width) were significantly and persistently reduced in all obese groups in comparison with lean controls. LF normalized units, LF/HF, and cardiac acceleration (reflecting sympathetic activation) were significantly increased in the ROB group. In IOB and OB groups, LF, but not nonlinear, measures were similar to lean controls, suggesting biphasic behavior of sympathetic tone, whereas nonlinear analysis showed a decreasing trend with the duration of obesity. Long-term HRV measures were significantly reduced in ROB and IOB. DISCUSSION: Autonomic nervous system changes in adolescent obesity seem to be related to its duration. Nonlinear methods of scatterplot and quadrant analysis permit assessment of autonomic balance, despite measuring different aspects of HRV.