Abnormal left ventricular diastolic filling in eccentric left ventricular hypertrophy of obesity

Obesity, hypertension, and the heart

Hypertension occurs more commonly in obese than in lean persons at virtually every age. A variety of endocrine, genetic, and metabolic mechanisms have been linked to the development of obesity hypertension. These include insulin resistance and hyperinsulinemia, increased serum aldosterone levels, salt sensitivity and expanded plasma volume in the presence of increased peripheral vascular resistance, a genetic predisposition, and possibly increased leptin levels. Pressure and volume overload are present in obese hypertensives. This leads to a mixed eccentric-concentric form of left ventricular hypertrophy and increases the predisposition to congestive heart failure. Weight loss, even in modest decrements, is effective in reducing obesity-hypertension, possibly by ameliorating several of the proposed pathophysiologic mechanisms. There are currently no specific recommendations concerning pharmacotherapy of obesity-hypertension because each drug group has pros and cons.

Obesity cardiomyopathy: pathophysiology and evolution of the clinical syndrome

Obesity produces an increase in total blood volume and cardiac output because of the high metabolic activity of excessive fat. In moderate to severe cases of obesity, this may lead to left ventricular dilation, increased left ventricular wall stress, compensatory (eccentric) left ventricular hypertrophy, and left ventricular diastolic dysfunction. Left ventricular systolic dysfunction may occur if wall stress remains high because of inadequate hypertrophy. Right ventricular structure and function may be similarly affected by the aforementioned morphologic and hemodynamic alterations and by pulmonary hypertension related to the sleep apnea/ obesity hypoventilation syndrome. The term obesity cardiomyopathy is applied when these cardiac structural and hemodynamic changes result in congestive heart failure. Obesity cardiomyopathy typically occurs in persons with severe and long-standing obesity. The predominant causes of death in those with obesity cardiomyopathy are progressive congestive heart failure and sudden cardiac death.

Left ventricular mass and function in young obese women

OBJECTIVE

Obesity is associated with a high mortality rate due to cardiovascular disease. Left ventricular (LV) hypertrophy has been described in relation to obesity. The aim of this study was to evaluate echocardiographically the LV mass and function in young obese women as compared to lean women with similar characteristics.

DESIGN

Prospective study.

SUBJECTS

Eighty-two young women (< or =40 y), with obesity degree varying from I to III (BMI from 30 to 50 kg/m2) were compared to eighty young lean women. All of them were normotensive, none had cardiovascular complaints or any previous history of pulmonary disease, and none were taking any medication. The LV mass was calculated by the Devereux and Reichek formula.

RESULTS

The LV mass was strongly increased in all obese groups (P<0.00003 to 0.000005) compared to lean subjects. LV mass adjusted indexes for height, BMI or volume were also increased compared to lean subjects and when adjusted for weight it was decreased. However when comparing LV mass/body surface area index this difference was not statistically significant. The linear regression analysis showed a strong association between the degree of obesity and LV mass, (r=0.52, P<0.001). Systolic and diastolic function in obese patients were similar to lean subjects, except for a lower E/A ratio in the obese group (P=0.005).

CONCLUSION

In asymptomatic young obese women, there are some echocardiographic findings suggesting early cardiac involvement that seems to be related to the degree of obesity.

Obesity and left ventricular diastolic function: noninvasive study in normotensives and newly diagnosed never-treated hypertensives

OBJECTIVE

To evaluate the influence of obesity, per se or associated with hypertension, on left ventricular (LV) diastolic function.

PATIENTS

Thirty-two obese newly-diagnosed never-treated hypertensives; 32 obese normotensives matched for age, sex and BMI with hypertensives; 32 lean newly diagnosed never-treated hypertensives and 32 lean normotensives, matched for age, sex and 24 h blood pressure (BP) with the obese subjects.

METHODS

Twenty-four-hour ambulatory blood pressure monitoring and digitized M-mode LV echocardiograms. PARAMETERS EVALUATED: Twenty-four-hour, day-time and night-time BP and heart rate, percentage nocturnal BP fall; LV end-diastolic diameter index, septal and posterior wall thickness, LV mass index, peak shortening and lengthening rate of LV diameter, peak thinning rate of LV posterior wall.

RESULTS

A main effect was found for obesity on LV diameter and LV mass and for hypertension on LV mass; LV systolic function was normal in all the subjects and similar among the four groups; LV diastolic function was significantly reduced in both obese groups with respect to lean ones. This difference persisted after correction of diastolic parameters for 24 h BP and heart rate, LV diameter and LV mass index and disappeared only after correction for body mass index. This latter was inversely related with diastolic parameters only in the obese groups.

CONCLUSIONS

Obesity is associated with a preclinical impairment of LV diastolic function in both normotensives and hypertensives; the diastolic impairment is independent of haemodynamic factors, such as 24 h BP and heart rate, and bears no relation to LV geometry in normotensives and only little relation in hypertensives, having therefore to be ascribed to obesity itself.

Obesidade, hipertensão arterial e suas influências sobre a massa e função do ventrículo esquerdo

Para avaliar as influências da obesidade e da hipertensão sobre a massa de ventrículo esquerdo (MVE), estudamos 121 mulheres divididas em 4 grupos: não-obesas normotensas (n = 25), não-obesas hipertensas (n = 30), obesas normotensas (n = 24) e obesas hipertensas (n = 42) quanto a parâmetros antropométricos, ecocardiográficos e de monitorização ambulatorial da pressão arterial (MAPA). As pacientes obesas hipertensas apresentaram maior MVE que os outros grupos - não-obesas normotensas, não-obesas hipertensas e obesas normotensas (167 ± 38,8 vs. 113 + 26,4; vs. 133 ± 26,5; vs. 132 ± 29,2g; p < 0,05, respectivamente) e maior diâmetro de átrio esquerdo (AE) quando comparadas aos grupos de não-obesas, tanto normotensas como hipertensas (36 ± 4,3 vs. 33 ± 5,1; vs. 35 ± 3,9mm; p < 0,05, respectivamente). Obesas normotensas apresentaram MVE similar à do grupo não-obesas hipertensas (133 ± 26,5 vs. 132 ± 29,5g; NS) e aumento de AE quando comparadas às não-obesas normotensas (35 ± 3,9 vs. 31 ± 4,6mm; p < 0,05). Detectou-se correlação entre a circunferência da cintura e a razão cintura-quadril com os níveis pressóricos à MAPA, assim como entre estas medidas e parâmetros ecocardiográficos que avaliam a massa cardíaca; o índice de massa corporal só se correlacionou ao diâmetro do AE. A correção da MVE pela altura ao invés da superfície corpórea aumentou a prevalência de hipertrofia de VE nas obesas (10,6 vs. 36,7%, p < 0,01), mas não nas não-obesas. Ausência de descenso noturno da pressão arterial sistólica à MAPA (non-dipper) foi mais prevalente nas pacientes obesas, hipertensas ou não; entretanto, as obesas hipertensas non-dippers não diferiram das dippers quanto à MVE. Nossos dados demonstram que a obesidade associada à hipertensão aumenta a MVE de modo mais importante do que as condições isoladamente. Concluímos, ainda, que pacientes obesas também apresentam alta freqüência de alterações do ritmo da pressão arterial de 24 horas, caracterizada por menor queda pressórica durante o sono.

Comparison of left ventricular mass and function in obese versus nonobese women <40 years of age

We evaluated, through Doppler echocardiography, left ventricular (LV) mass and function in 82 obese young women (aged <40 years) who were asymptomatic, without any cardiovascular or pulmonary disease compared with a lean control group matched by age and height. LV mass, LV mass/height, and LV mass/volume were increased in obese women, and a lower LV E- and A-wave velocity ratio was noted, suggesting early cardiac involvement.

Diastolic compliance is reduced in obese rabbits

Obesity often leads to symptoms of cardiopulmonary congestion associated with normal systolic but abnormal diastolic function. This study analyzed alterations in passive diastolic compliance in obesity using the rabbit model. New Zealand White rabbits were fed a normal (n=8) or 10% added fat diet (n=8). After 12 weeks, rabbits fed the high fat diet developed obesity (5.34+/-0.11 versus 3.68+/-0. 04 kg, P</=0.05) and left ventricular hypertrophy (1.37+/-0.07 versus 0.98+/-0.03 g dry weight, P</=0.05). Compliance was assessed with the isolated heart preparation by analyzing the passive end-diastolic left ventricular pressure-volume relationship. The pressure-volume relation was fit to an exponential function by regression analysis; results showed that the modulus of stiffness was greater in obese than in lean rabbits (1.21+/-0.16 versus 0. 83+/-0.05, P</=0.05), indicating that diastolic compliance was reduced. Computer simulation analyses suggested that an isolated reduction in diastolic compliance may contribute to elevated cardiac filling pressures and exercise intolerance. These data suggest that diastolic compliance is reduced early in the development of obesity and may be an important component in the reduction of cardiac reserve in obesity.

Reduced cardiac contractile responsiveness to isoproterenol in obese rabbits

Although obesity is characterized by increased sympathetic nervous system activity, there is often a paradoxical reduction in cardiovascular end-organ response to sympathetic stimulation. Mechanisms involved in reduced sympathetic responsiveness in obesity have not been well characterized. Therefore, we determined cardiac contractile responsiveness to beta-stimulation in the obese rabbit model using both isolated heart (IH) and isolated papillary muscle (IPM) preparations. Female New Zealand White rabbits were fed control (IH: n=9; IPM: n=6) or 10% fat diets (IH: n=9; IPM: n=7) for 12 weeks. Contractile responsiveness in the IH was determined using a modified Langendorff preparation to evaluate the dose-response relationship between isoproterenol and 1) peak developed pressure/g of left ventricular wet weight and 2) maximal rate of pressure development (+dP/dt/P). Contractile responsiveness in the IPM was determined using right ventricular papillary muscles to evaluate the dose-response relationship between isoproterenol and (1) peak developed tension (T)/mm2 cross-sectional area (CSA) and (2) maximal rate of tension development (dT/dt/CSA). In the IH, baseline and maximum developed pressure/g were reduced in obese rabbits by 37% and 31%, respectively (P< or =.05). In the IPM, baseline and maximum T/CSA responses were reduced in obese rabbits by 59% and 33%, respectively (P< or =.05). Potency of isoproterenol as reflected by the EC50 did not differ between lean and obese animals in either preparation. These results demonstrate that left ventricular contractility in obesity is reduced at baseline and in response to stimulation with isoproterenol and suggest that decreased responsiveness to beta-stimulation may be a factor in the obesity-related systolic dysfunction.

Nonpharmacologic approaches to hypertension. Weight, sodium, alcohol, exercise, and tobacco considerations

Weight loss decreases blood pressure, and this change can be sustained over the long-term when the lower weight is maintained. Salt restriction may be effective in blood pressure control only in salt-sensitive individuals. Heavy drinkers (those who drink more than three drinks [30 mL] daily) experience deleterious effects such as hypertension and more cardiovascular risk factors. Consequently, they should be advised to reduce alcohol intake to less than 30 mL daily. Endurance training with dynamic exercise appears to be beneficial for hypertensive patients, although recommendation guidelines are still imprecise. Finally, smoking cessation has not been proven to decrease blood pressure levels but should nonetheless be recommended because of its favorable effects on cardiovascular morbidity and mortality.

Left ventricular filling in arterial hypertension. Influence of obesity and hemodynamic and structural confounders

We assessed the relations of left ventricular filling to load and geometry by Doppler echocardiography in 80 normotensive subjects (40 normal-weight [36 +/- 12 years, 24 women] and 40 obese [35 +/- 13 years, 24 women]) and 61 hypertensive subjects without silent coronary heart disease (29 normal-weight [43 +/- 13 years, 15 women] and 32 obese [42 +/- 13 years, 19 women]) and comparable left ventricular midwall performance. Left ventricular mass divided by height to the 2.7 power was higher in all groups than in normotensive normal-weight subjects (all P < .0001) and in hypertensive than normotensive obese subjects (P < .001). After controlling for age, sex, blood pressure, and heart rate, isovolumic relaxation time was prolonged in hypertensive subjects and normotensive obese subjects compared with normotensive normal-weight subjects (all P < .0001). Body mass index, left ventricular dimension and mass, and circumferential end-systolic stress did not influence these differences. In pooled groups, prolonged isovolumic relaxation time was predicted by high mean blood pressure (beta = 0.52, P < .001), low end-systolic stress (beta = -0.33, P < .001), increased left ventricular mass (beta = 0.24, P < .004), and high body mass index (beta = 0.14, P < .05, multiple R = .72, SEE = 16.5 milliseconds, P < .0001). Between-group differences in peak early transmitral flow velocity, the deceleration time of early filling velocity, and the ratio of early to late left ventricular filling disappeared after controlling for left ventricular mass. Thus, (1) isovolumic relaxation time is prolonged in both arterial hypertension and obesity; (2) the presence of obesity does not significantly increase isovolumic relaxation time in hypertension; and (3) abnormalities of left ventricular filling in arterial hypertension are offset after controlling for left ventricular mass.

Left ventricular diastolic function in hypertension and role of plasma glucose and insulin. Comparison with diabetic heart

BACKGROUND

Experimental production of glucose intolerance has been associated with increased diastolic stiffness of the left ventricle, accompanied by interstitial fibrosis. Because carbohydrate metabolism is altered in hypertension, we undertook the present study to assess the relation of diastolic dysfunction in hypertension to plasma glucose and insulin concentrations. The latter are also affected by obesity. To facilitate this analysis, we studied moderately obese hypertensives. Elucidation of these relations was then sought in diabetic subjects.

METHODS AND RESULTS

Subjects undergoing catheterization for chest pain were included in the study when significant coronary disease was not present. In groups 1 (lean), 2 (obese), 3 (lean hypertensive), and 4 (obese hypertensives), intraventricular pressures and volumes were determined. Fasting plasma glucose, insulin, hemoglobinAIC, and glucose tolerance were assessed. Basal ejection fraction and end-systolic wall stress were normal in the four groups. Chamber stiffness was significantly elevated in the hypertensives and was higher in group 4 than in group 3 (P < .05). Diastolic dysfunction was correlated with fasting blood glucose (r = .69, P < .006) but not with plasma insulin or left ventricular mass. Chamber stiffness was also increased in diabetics, with a larger effect in the obese.

CONCLUSIONS

Hypertension is associated with increased diastolic stiffness of the left ventricle, which is enhanced by moderate obesity, and abnormal carbohydrate metabolism. Experimentally and in humans, hypertension is associated with interstitial fibrosis of mycardium, the presumed basis for the diastolic dysfunction. Chamber stiffness in group 4 hypertensives was similar to that in the lean diabetics but less than that in the obese diabetics. Although the latter exhibited a correlation with plasma hemoglobinAIC, the large rise in stiffness suggests a potential role for growth factors in further alteration of myocardial composition.

Left ventricular filling pattern in uncomplicated obesity

To determine if uncomplicated obesity is associated with systolic dysfunction or impairment of left ventricular (LV) filling, 40 normotensive, white, asymptomatic, obese subjects (16 men and 24 women, mean +/- SD age 35 +/- 13 years; body mass index 36 +/- 6 kg/m2) and 40 normotensive, normal-weight, white volunteers matched for age and sex distribution, were studied by Doppler echocardiography. Endocardial and midwall shortening did not show differences between groups (obese = 33 +/- 4% and 17 +/- 2%; normal weight = 33 +/- 3% and 18 +/- 2%, respectively). LV mass index was higher in obese than in normal-weight subjects (p <0.0001). Obese persons had prolonged isovolumic relaxation time (p <0.0001), lower transmitral peak early diastolic filling wave (E) velocity (p <0.02), higher E velocity deceleration time (p <0.002) and lower E/atrial diastolic filling wave (A) flow velocity ratio (p <0.01) than did normal-weight subjects, even after controlling for age and blood pressure. Between-group differences in E and E velocity deceleration time disappeared when controlling for LV mass index, whereas prolonged isovolumic relaxation time in obesity was independent of LV mass, chamber dimension, and end-systolic stress. LV filling variables were not statistically related to endocardial or midwall shortening, both as absolute value or as a percentage of that predicted from wall stress. We conclude that uncomplicated obesity is associated with primary impairment of LV isovolumic relaxation; abnormalities of early passive filling flow in obesity are associated with increased LV mass.

Obesity and left ventricular diastolic dysfunction

To assess the influence of obesity on left ventricular function, 20 obese women (mean body mass index (BMI) 33.8 +/- 3.1 kg/m2 and mean age 31.1 +/- 2.4 years) without evidence of heart disease were evaluated by echocardiography. Obese subjects had greater left ventricular mass index (103 +/- 22 g/m2, 76 +/- 18 g/m2; P < 0.0001) and augmented fractional shortening (39 +/- 2.6%, 36 +/- 0.1%; P < 0.0001) than normals. Isovolumic relaxation time was prolonged in the obese group (92 +/- 11 ms) as compared with the control group (76 +/- 11 ms; P < 0.0001). The ratio of peak early and atrial filling velocities was significantly lower (1.2 +/- 0.4, 1.9 +/- 0.6; P < 0.0001) and atrial contribution was higher (39 +/- 9, 25 +/- 5; P < 0.0001) in obese subjects than in normals. Shortened deceleration time was measured in obese subjects (142 +/- 30, 179 +/- 20 ms; P < 0.0001). In conclusion, obesity causes relaxation and early filling abnormalities and diastolic filling is compensated by augmented atrial contribution. Diastolic dysfunction is an early indicator of cardiac involvement in obesity.

Influence of left ventricular mass on left ventricular diastolic filling in normotensive morbid obesity

To identify factors influencing left ventricular (LV) diastolic filling in patients with morbid obesity, we performed transthoracic and Doppler echocardiography on 50 subjects whose actual body weight was > or = twice their ideal body weight and on 50 normal lean control subjects. The transmitral Doppler E/A ratio and E wave deceleration half-time were used to assess LV diastolic filling. Significant negative correlations were seen between the E/A ratio and the LV internal dimension in diastole (r = 0.819, p = 0.0001), systolic blood pressure (r = 0.751, p = 0.0001), LV end-systolic wall stress (r = 0.782, p = 0.0001), and LV mass/height index (r = 0.901, p = 0.0001). Significant positive correlations were seen between the E wave deceleration half-time and the LV internal dimension in diastole (r = 0.743, p = 0.0001), systolic blood pressure (r = 0.789, p = 0.0001), LV end-systolic wall stress (r = 0.828, p = 0.0001), and LV mass/height index (r = 0.831, p = 0.0001). No correlation was seen between diastolic blood pressure and either index of LV diastolic filling. Thus increasing LV mass is associated with progressive impairment of LV diastolic filling in morbidly obese individuals. The aforementioned alterations in LV loading conditions may contribute to impairment of LV diastolic filling directly or by increasing LV mass.

Prevalence and predictors of audible physiological third heart sound in a population sample aged 36 to 37 years

BACKGROUND

A physiological third heart sound (S3) is common in youth but allegedly very rare after the age of 40 years. The mechanism of its disappearance is not known. The aim of this work was to study the prevalence and predictors of physiological S3 in a population-based sample of persons approaching 40 years of age.

METHODS AND RESULTS

A random sample of 120 persons born in 1954 was invited; 93 (42 men) entered the study. Their physical activity, alcohol and tobacco consumption, and salt intake were quantified by diary follow-up. The presence of an S3 was determined by auscultation and confirmed by phonocardiography. Left ventricular (LV) size, mass, and systolic function were assessed by M-mode echocardiography and LV filling by Doppler velocimetry of transmitral flow. An audible S3 was detected in 22 subjects, 1 of whom had heart disease. The prevalence of physiological S3 was 23.1%. Subjects with physiological S3 had a lower body mass index (22.3 +/- 2.8 versus 24.6 +/- 4.1 kg/m2 [mean +/- SD], P = .005), lower heart rate (63 +/- 7 versus 68 +/- 10 beats per minute, P = .015), higher peak early diastolic transmitral velocity (67 +/- 10 versus 58 +/- 8 cm/s, P = .002), and higher acceleration of early diastolic velocity (717 +/- 148 versus 622 +/- 122 cm/s2, P = .012) than those without S3. No differences were noted in the lifestyle characteristics, blood pressure, or LV mass and systolic function. Body mass index and peak early diastolic transmitral velocity were independent predictors of physiological S3 in logistic regression analysis.

CONCLUSIONS

Nearly one fourth of persons approaching their forties still have an audible physiological S3. The presence of S3 is predicted by leanness and a high early diastolic LV inflow velocity; the disappearance of S3 is unlikely to be secondary to increasing blood pressure and relative LV hypertrophy, as is widely presented, but reflects a more primary age-related alteration of LV early diastolic function.

Obesity and the heart

Obesity can result in alterations in cardiac structure and function even in the absence of systemic hypertension and underlying organic heart disease. Increased total blood volume creates a high cardiac output state that may cause ventricular dilatation and ultimately eccentric hypertrophy of the left (and possibly the right) ventricle. Eccentric left ventricular (LV) hypertrophy produces diastolic dysfunction. Systolic dysfunction may ensue due to excessive wall stress if wall thickening fails to keep pace with dilatation. This disorder is referred to as obesity cardiomyopathy. The presence of systemic hypertension in obese individuals facilitates development of LV dilatation and hypertrophy. Congestive heart failure may occur in such individuals, and may be attributable to LV diastolic dysfunction or to combined LV diastolic and systolic dysfunction. The sleep apnea/obesity hypoventilation syndrome occurs in 5% of morbidly obese individuals and is potentially life-threatening. Treatment of obesity cardiomyopathy consists of weight loss, salt restriction, and diuretics. Digitalis and vasodilators may be useful in selected cases. Central obesity is probably a risk factor for the development of coronary heart disease. Alterations in lipid and insulin metabolism may facilitate development of coronary heart disease in obese patients.

Cardiac manifestations of cocaine abuse: a cross-sectional study of asymptomatic men with a history of long-term abuse of "crack" cocaine

OBJECTIVES

The objective of this study was to evaluate the prevalence of cardiac abnormalities in young, asymptomatic long-term "crack" cocaine abusers.

BACKGROUND

Although the cardiac complications of cocaine abuse have received widespread attention, the prevalence of cardiac abnormalities in asymptomatic long-term cocaine abusers is unknown.

METHODS

History, physical examination, electrocardiogram (ECG) and echocardiogram were performed in 52 consecutive long-term cocaine abusers admitted to a drug rehabilitation program. Findings were compared with those in 14 age-matched normal volunteers and 14 age-matched normotensive patients admitted to a psychiatric service who had a pattern of smoking and alcohol consumption similar to that of the study patients.

RESULTS

The ECG findings were abnormal in 29% of cocaine abusers, and included nonspecific ST-T wave changes in 15%, abnormal ST segment elevation in 10%, old inferior infarction in 2%, old anteroseptal infarction in 2% and abnormal precordial R wave progression in 10%. When compared with normal volunteers and control patients, cocaine abusers had increased left ventricular posterior wall thickness (1.12 vs. 0.76 and 0.85 cm, respectively, p < 0.0001), increased septal thickness (1.13 vs. 0.76 and 0.86 cm, p < 0.001) and higher left ventricular mass index (142 vs. 84 and 94 g/m2, p < 0.0001). Left ventricular diastolic filling variables did not differ significantly among the three groups. Diastolic filling variables were similar in cocaine abusers with and without left ventricular hypertrophy, and the prevalence of left ventricular hypertrophy did not differ significantly between those who used no alcohol or < 35 ml/week of alcohol and those who consumed > or = 500 ml/week of alcohol. Left ventricular segmental wall motion abnormalities were present in 11 subjects (21%) and the ejection fraction was decreased (< 0.45) in 2 (4%).

CONCLUSIONS

Electrocardiographic and echocardiographic abnormalities are common in long-term cocaine abusers. Despite the frequent occurrence of left ventricular hypertrophy, Doppler-derived diastolic filling pattern was not altered. Concomitant alcohol use did not affect the prevalence of these abnormalities.

The influence of obesity on left ventricular filling and systolic function

Little information on the possible influence of obesity on diastolic function is available. Thus we studied 24 asymptomatic obese volunteers (greater than 120% ideal body weight; mean 153 +/- 30%), aged 34 +/- 11 years. Each obese subject was matched for age, height, and sex, with a healthy normal-weight control subject. Isovolumic relaxation time (IVRT) and diastolic filling indexes were determined by pulsed Doppler echocardiography. The IVRT was significantly prolonged in the obese group (84 +/- 17 msec) as compared with the control group (57 +/- 13 msec; p less than 0.0002). Multiple regression analysis showed that percentage of ideal body weight was the most important predictor of peak early filling velocity (r = 0.59, p less than 0.005) and mean deceleration rate of early filling (r = 0.61, p less than 0.005) in the obese group. However, age as compared with percentage of ideal body weight was a more important determinant of the relative distribution of early and atrial filling, such as peak early-to-atrial filling velocity ratio (r = -0.75, p less than 0.0001). Ejection fraction, heart rate, and blood pressure did not differ between the obese and control groups. In conclusion, obesity is associated with preclinical abnormalities of IVRT, which may reflect impaired relaxation. The IVRT may be useful in the early detection of left ventricular dysfunction in obesity. Last, studies comparing Doppler indexes of diastolic filling among groups must control for potential differences in percentage of ideal body weight.

Left ventricular hypertrophy. Its relationship to obesity and hypertension

Hypertension and obesity are closely related. Obese patients tend to have increased intravascular volume and cardiac output and decreased total peripheral vascular resistance and plasma renin activity. Lean patients with essential hypertension usually have increased total peripheral resistance. Left ventricular adaptation in obesity consists of eccentric left ventricular hypertrophy (LVH), regardless of the level of arterial pressure. Obesity and hypertension occurring together place a dual burden on the left ventricle and are associated with systolic and diastolic dysfunction, lipid abnormalities, insulin resistance, and a propensity for frequent, complex ventricular arrhythmias. Congestive heart failure and sudden death are common sequelae of obesity-hypertension and LVH. Treatment should include vigorous efforts at weight reduction and sodium restriction. Diuretics are ideal agents from a hemodynamic standpoint but often do not improve the total risk profile, with the possible exception of indapamide (Lozol). Calcium blockers may be ideal agents because of their favorable effects on both hemodynamics and total cardiovascular risk profile.