Biomedical subjects

V Di Bello

Publications and source records attributed to V Di Bello.

At least 19 recordsLinked to original sources

PubMed2006

Myocardial systolic strain abnormalities in patients with acromegaly: a prospective color Doppler imaging study.

BACKGROUND: Heart abnormalities are frequent findings in patients with acromegaly: systolic abnormalities are considered to be secondary to diastolic changes. AIM: The aim of the study was to evaluate whether early systolic abnormalities might be revealed in acromegalic patients using the high sensitive color Doppler myocardial imaging (CDMI) technique. PATIENTS AND METHODS: Twenty-two consecutive acromegalic patients with active untreated disease (ACROUNTR) were evaluated at baseline and after a 6-month course with SS analogs (SSa) (ACROSSa); 25 healthy subjects served as controls. All subjects underwent conventional 2D-color Doppler echocardiography, pulse wave tissue Doppler imaging (PW-TDI) and CDMI. RESULTS: Mean left ventricular (LV) ejection fraction did not differ in ACROUNTR and in controls; at variance, ACROUNTR patients had reduced mean LV diastolic function (E/A ratio: 0.96+/-0.3 vs controls: 1.6+/-0.3; p<0.002). Impairment of global LV diastolic function was confirmed by PW-TDI in ACROUNTR patients having a normal systolic function. Regional myocardial systolic strain (epsilon) and strain rate (SR) values, indices of regional systolic heart deformation, were lower in ACROUNTR [epsilonsys (S) -19.8+/-2.9 and epsilonsys (L): -17.7+/-2.2] than in controls [epsilonsys (S): -27.9+/-3.8; p<0.001 and epsilonsys (L): -25.3+/-2.6; p<0.001]. In addition, the early phase of diastolic function, evaluated using SR parameters, was impaired in acromegalic patients (p<0.005 vs controls). Strain and SR values were related to serum GH and IGF-I levels (p<0.02) and greatly improved after a 6-month course with SSa [epsilonsys (S) improved to -23.8+/-3.8 (p<0.05) and epsilonsys (L) improved to -24.7+/-2.4 (p<0.03)]. CONCLUSIONS: Our study confirms that ACROUNTR patients have impaired diastolic function. More important, our study clearly shows that ACROUNTR patients have an impairment of regional myocardial systolic function, which is not secondary to diastolic changes. These intramyocardial functional abnormalities improved during medical treatment of acromegaly. It is conceivable that GH-IGF-I excess has detrimental effects either on the diastolic or the systolic phases of heart function.

Acromegaly↗

PubMed2006

Relationship between preclinical abnormalities of global and regional left ventricular function and insulin resistance in severe obesity: a Color Doppler Imaging Study.

BACKGROUND: The aim of this study was to evaluate the relationship between insulin resistance and preclinical abnormalities of the left ventricular structure and function detected in severe obesity by Color Doppler Myocardial Imaging (CDMI). Forty-eight consecutive severely obese patients (Group O) (11 males, 37 females, mean age 32.8+/-7 years) were enrolled. Forty-eight sex- and age-matched non-obese healthy subjects were also recruited as controls (Group C). All subjects underwent conventional 2D-Color Doppler echocardiography and CDMI. The homeostasis model assessment insulin resistance index (HOMA-IR) was used to assess insulin resistance results. Obese subjects had a greater left ventricular mass index (by height) (58.8+/-14 g/m(2.7)) than controls (37+/-8 g/m(2.7)) (P<0.0001), owing to compensation response to volume overload caused by a greater cardiac output (P<0.02). Preload reserve was increased in obese subjects, as demonstrated by a significant increase in left atrial dimension (P<0.0001). Obese patients had a slightly reduced LV diastolic function (transmitral E/A ratio: Group O, 1.1+/-0.8 vs Group C, 1.5 +/-0.5; P<0.002). Cardiac deformation assessed by regional myocardial systolic strain and strain rate (SR) values was significantly lower (abnormal) in obese patients than in controls, both at the septum and lateral wall level. These strain and SR abnormalities were significantly related to body mass index. In addition, the early phase of diastolic function, evaluated using SR, was compromised in obese patients (P<0.001). The HOMA-IR values in obese patients were significantly higher (3.09+/-1.6) than those determined in the control group (0.92+/-0.5) (P<0.0001). The HOMA-IR values, in the obese group, were significantly related to systolic strain and SR values sampled at the septum level (P<0.0001). CONCLUSION: In conclusion, this study has demonstrated that obese patients pointed out systolic structural and functional abnormalities at a preclinical stage, in particular through strain and SR analysis; on the other hand, those altered CDMI parameters well distinguish obese subjects as compared with the control group. Furthermore, another main finding of the study was that myocardial deformation (systolic strain) could have a correlation with insulin resistance level.

Adult↗

PubMed2005

Quantification methods in contrast echocardiography.

New technologies and the availability of new echo-contrast agents have resulted in advances of diagnostic and prognostic indications of left ventricular opacification (LVO) and myocardial perfusion. The clinical diagnostic value of ultrasound contrast media for LVO and its impact on the clinical decision-making process has been demonstrated in several studies. Recent research aims at developing new quantitative software to improve the delineation of the endocardial border, to assess 3D myocardial perfusion for more accurate regional/global LV function measurements, and to evaluate 4D intra-cardiac flow dynamics. Furthermore, a general consensus has been reached on the incremental value of myocardial contrast echocardiography (MCE) for obtaining additional information in both chronic and acute coronary artery disease (CAD) patients and on the possibility to make quantitative measurements of microvascular damage. Q-contrast is a new software system which provides quantitative measurements to generate parametric images of microcirculatory flow. In a research project including 120 patients, Q-contrast software has been tested to assess the role of contrast in AMI (Acute Myocardial Infarction Contrast Imaging (A.M.I.C.I. Study); good agreement between parametric MCE and SPECT has been found. Preliminary results further confirm that quantitative MCE may provide additional clinical value over qualitative information for the assessment of LV function and of the effects of coronary artery disease on the myocardial microcirculation (viability, ischemia or infarct).

Aged↗

PubMed2003

Coronary microcirculation into different models of left ventricular hypertrophy-hypertensive and athlete's heart: a contrast echocardiographic study.

The study was carried out in two different models of left ventricular hypertrophy: athlete's heart and essential arterial hypertension. Three groups of strictly age-matched males were studied: one group of 10 young adult untreated essential hypertensive patients (H), a second group of 10 athletes (A), and a group of 10 healthy individuals as controls (C). A Sonos 5500 echograph with S4 harmonic transducer was used with Levovist (ultrasonic tracer) before and after dipyridamole injection; digitised images of quantitative myocardial contrast echocardiography were collected with Power Harmonic Doppler. Angio images were analysed using dedicated PC software by placing a region-of-interest on the septum. Peak intensity, half-time (HT), the area under the curve of appearance and disappearance of microbubbles at 2/3 of PI, both in absolute and indexed values (/LVMi), were sampled. The per cent increase of PI after dipyridamole was significantly higher in C (+73%, P < 0.01) than in H (+31%) and in A (+33%) (P < 0.05). The area of appearance was significantly lower in H in comparison with C and A, both at rest and after vasodilatation. The disappearance area after dipyridamole was significantly higher in C and in A (+124%) than in H (+104%) (P < 0.05). Some hypothesis could be made: an impairment in the coronary microcirculatory function in hypertensive patients could be because of an in-crease in the arteriolar resistance. Angiogenesis and several different functional adaptations are the mechanisms that allow an optimal distribution of oxygen and of substrates to the hypertrophied myocardium of the athletes.

Adult↗

PubMed2003

Blood pressure independent association of microalbuminuria and left ventricular hypertrophy in hypertensive men.

BACKGROUND: Rather unique amongst the prognostic predictors, microalbuminuria (MA, albuminuria: 15-200 microg min-1) is associated with several cardiovascular risk factors including left ventricular hypertrophy (LVH). The relationship, usually assumed to reflect an increased blood pressure (BP) load on the heart and the kidney, may, however, represent more than a haemodynamic correlate. METHODS: To evaluate this possibility, we related MA to left ventricular mass index (LVMI) and other functional and structural echocardiographic parameters, office and 24-h BP, weight, lipids and smoking status in 330 never treated nondiabetic hypertensive men. RESULTS: The risk of MA increased linearly by ascending quartiles of LVMI and was 2.3-fold higher in the presence of LVH after adjustment for age, left atrial size, mean fractional shortening. Systolic BP, either office or 24 h, and smoking status were the only additional independent predictors in multivariate logistic regression models. The BP-adjusted risk of MA was about twofold higher in patients with LVH, either concentric or eccentric, and neutral in those with concentric remodelling compared with normal geometry. CONCLUSIONS: The association between elevated LVMI and MA independent of several other potential confounders, systolic BP in particular, is consistent with the existence of cardiac albuminuric factors, possibly of hormonal nature, which are to be identified more precisely. The extent to which LVH explains the predictive power of MA for morbid events independent of the BP load remains unknown.

Albuminuria↗

PubMed2002

Microalbuminuria, an integrated marker of cardiovascular risk in essential hypertension.

This paper reviews the existing epidemiological and clinical evidence about the relationships of non-diabetic microalbuminuria with cardiovascular risk factors such as elevated blood pressure (BP), systolic particularly, cardiac hypertrophy, adverse metabolic status, smoking habits, elevated angiotensin II levels, endothelial dysfunction, acute and perhaps subclinical inflammation. Because of that unique property of reflecting the influence of so many clinically relevant parameters, microalbuminuria may legitimately be defined as an integrated marker of cardiovascular risk, an unique profile among the several prognostic predictors available to stratify risk in hypertensive patients. Recent cohort studies also showed associations with cardiovascular morbidity and mortality independently from conventional atherogenic factors. This behaviour, whose understanding still needs further elucidation, suggests to measure albuminuria and to screen patients at a higher absolute risk in whom preventive treatment is expected to be more beneficial than in those with a lower absolute risk.

Albuminuria↗

PubMed2002

Coronary microcirculation in essential hypertension: a quantitative myocardial contrast echocardiographic approach.

AIMS: The aims of the present study were: (a) to demonstrate whether quantitative myocardial contrast echocardiography can detect the increase in coronary flow induced by dipyridamole infusion vasodilation through the myocardial opacification due to the transit of microbubbles, both at rest and after dipyridamole induced vasodilation; (b) to explore the coronary microcirculatory function before and after dipyridamole in two different models: asymptomatic and relatively young hypertensive patients with a mild degree of left ventricular hypertrophy, and healthy controls. METHODS AND RESULTS: Two groups of strictly age-matched males were studied (case-control study): 10, relatively young and asymptomatic essential hypertensive patients with a mild degree of left ventricular hypertrophy with a normal left ventricular function, and 10 healthy controls. The main findings were: the microbubbles' appearance area was significantly lower in hypertensive patients than in controls (P<0.05) because of a significantly lower time to peak. The peak intensity at rest was higher in hypertensives than in controls (P<0.05); but the per cent increase after vasodilatory stimulus was significantly higher in controls (+71% in controls vs +31% in hypertensives; P<0.05). The microbubbles' disappearance area was comparable in both groups at rest; the per cent increase of this parameter after dipyridamole was significantly higher in controls (+124%) than in hypertensives (+90%) (P<0.05). The results achieved in this study documented that the coronary microcirculation in hypertensive patients presenting a mild degree of left ventricular hypertrophy, explored with quantitative myocardial contrast echocardiography, showed a different behaviour in comparison with controls, in the vasodilatory response to dipyridamole. CONCLUSION: The coronary microcirculation in hypertensives showed a reduced vasodilation capacity of the resistance arterioles under dipyridamole induced vasodilatation, and a possible impairment of the endothelium dependent vasodilation. This happened despite an increase in the left ventricular mass, where the relation between capillary bed distribution and hypertrophied myocardium (rarefaction phenomenon) is not completely respected.

Adult↗

PubMed2001

Echocardiographic ultrasonic tissue characterization in a case of Fabry's disease following renal transplantation.

We report a case of Fabry's disease where stabilization of progressive cardiac involvement was recorded in a 29-yr-old Caucasian man, to our knowledge, for the first time by ultrasonic tissue characterization echocardiography after 1 yr of successful renal transplantation. Three echocardiographic evaluations have been made: the first 3 months before, the second 6 months after, and the third 1 yr after kidney transplantation. The myocardial structural damage - evaluated by integrated backscatter index - shows a persistence of the impairment of intrinsic myocardial contractility at septum level, probably due to coexistent hypertensive status, which is able to induce per se alterations of myocardial textural parameters. On the other hand, the cyclic variation index at posterior free wall, which is less dependent on strictly hemodynamic factors than the septum, appears quite normal at the third observation. These data could reflect the improvement of the ultrastuctural myocardial findings in relation to renal transplantation, which could correct not only renal failure but also the enzymatic deficiency by replacement of alpha-galactosidase A through the transplanted kidney.

Adult↗

PubMed2001

Cyclic variation of the myocardial integrated backscatter signal in hypertensive cardiopathy: a preliminary study.

BACKGROUND: Ultrasound tissue characterization studies realized through integrated backscatter analysis with end-diastolic sampling in hypertensive cardiopathy have demonstrated that abnormalities in the left ventricular myocardial ultrasonic texture are present in extreme forms of left ventricular hypertrophy (LVH). Such abnormalities are not evident in the athlete's heart. The aim of the present study was to analyze the ultrasonic backscatter myocardial indexes both as peak end-diastolic signal intensity and as cardiac-cyclic variation in two models of LVH: hypertensive cardiopathy and athlete's heart. METHODS: Three groups of 10 subjects each, all men of mean age (31.6+/-3.5 years), and of comparable weight and height, were analyzed. Group A comprised 10 cyclists of good professional level, while hypertensive patients were grouped in Group H. Both groups presented a comparable left ventricular mass (LVM). Group C included 10 healthy subjects acting as controls. The men with hypertension were selected on the basis of the results of ambulatory monitoring of the blood pressure according to ISH-World Health Organization guidelines (International Society of Hypertension). A 2D-color Doppler echocardiography with a digital echograph Sonos 5500 (Agilent Technologies, Andover, Massachusetts, USA), was carried out on all the subjects in the study for conventional analysis of the LVM and function. The ultrasonic myocardial integrated backscatter signal (IBS) was analyzed with an 'acoustic densitometry' module implemented on a AT echograph. The signal was also sampled with a region of interest (ROI) placed at interventricular septum and at posterior left ventricular wall level. The systo-diastolic variation of the backscatter was also considered, as cyclic variation index (CVIibs). RESULTS: According to the inclusion criteria, the LVM was comparable in groups A and H, but it was significantly higher than group C (left ventricular mass (body surface) (LVMbs)=154.5+/-18.7 (A), 146.8+/-25.5 (H), 101.4+/-12.4 (C), p < 0.001). The end-diastolic IBS did not show significant statistical differences among the three groups. The CVI(IBS) both at septum (30.5+/-5.3 (A), 13.2+/-13.1 (H), 27.2+/-7.3(C), p < 0.002) and posterior wall level (43.7+/-9.1 (A), 16.5+/-12.1 (H), 40.7+/-9.1 (C), p < 0.001) though, was significantly lower in the hypertensive patients than in both the athletes and the control group, where the results were comparable. CONCLUSION: A significant alteration of the myocardial CVIibs (both for septum and posterior wall) was found in the hypertensive model. This was probably the expression of an alteration in the intramural myocardial function.

Adult↗

PubMed2001

Microalbuminuria, pulse pressure, left ventricular hypertrophy, and myocardial ultrasonic tissue characterization in essential hypertension.

Microalbuminuria (UAE) may be considered a marker of systemic vascular dysfunction, while pulse pressure (PP) is an indicator of the stiffness of vascular conduits. Both these parameters, together with left ventricular hypertrophy (LVH), are linked to cardiovascular morbidity in hypertensive patients. The aim of this study was the analysis of the possible relationships among UAE, PP, and LVH with ultrasonic myocardial textural parameters, which are altered in hypertensives patients. A group of male (n = 70) essential hypertensive patients (mean age: 58 +/- 7 yr) was analyzed with a group of age-comparable normotensive healthy subjects as controls (n = 32). Ambulatory blood pressure monitoring (ABPM) was performed with an oscillometric monitor; UAE was measured by nephelometry. A conventional 2D-Doppler echocardiography (to analyze left ventricular mass: LVM) and a quantitative analysis of the echocardiographic digitized imaging with the use of a calibrated digitization system (to calculate the septum and the posterior wall textural parameters) were performed on all subjects. The myocardial mean gray level was calculated to derive the cyclic variation index (CVI). The CVI was significantly lower in hypertensives both for the septum (- 16.3 +/- 22.8 vs 34.7 +/- 15.3%; p < 0.001) and for the posterior wall (- 15.2 +/- 23.6 vs 38.2 +/- 15.4%; p < 0.001). A significant negative correlation was found between logUAE and the CVI of the septum (r = -0.42; p < 0.001), between the PP and the CVI of the septum (r = -0.40; p < 0.002) and between the CVI and the LVM (r = -0.38; p < 0.001). Multiple regression analysis having as dependent variable the CVI at septum level showed as significantly related independent variables: PP (p < 0.01), logUAE (p < 0.001), and LVM (p < 0.05) (multiple R: 0.76, squared multiple R: 0.57; p < 0.001). It was found that LVM, logUAE, and PP are all correlated with textural parameters, and the CVI can be considered a sensitive parameter in the identification of an abnormal myocardial texture in hypertension. A high level of arterial stiffness and the presence of vascular dysfunction in essential hypertension could participate in the determination of myocardial alterations and permit the identification of patients with the worst prognosis in terms of morbidity or mortality due to cardiovascular events.

Albuminuria↗

PubMed2001

Effect of levothyroxine on cardiac function and structure in subclinical hypothyroidism: a double blind, placebo-controlled study.

Subclinical hypothyroidism (sHT) affects 5-15% of the general population; however, the need of lifelong L-T(4) therapy is still controversial. As myocardium is a main target of thyroid hormone action, we investigated whether sHT induces cardiovascular alterations. Twenty sHT patients were randomly assigned to receive placebo or L-T(4) therapy and were followed for 1 yr. Twenty sex- and age-matched normal subjects served as controls. Doppler echocardiography and videodensitometric analysis were performed in all subjects. Myocardium textural parameters were obtained as mean gray levels, which were then used to calculate the cyclic variation index (CVI; percent systolic/diastolic change in mean gray levels). Patients had a significantly higher isovolumic relaxation time (3.1 +/- 0.5 vs. 2.6 +/- 0.6; P < 0.03), peak A (0.77 +/- 0.16 vs. 0.56 +/- 0.13 m/s; P < 0.01), and preejection/ejection time (PEP/ET) ratio (0.72 +/- 0.05 vs. 0.57 +/- 0.06; P < 0.03) and a lower CVI (P < 0.0001) than controls. CVI was inversely related to TSH level (P < 0.0001) and PEP/ET ratio (P < 0.01). L-T(4)-treated patients showed a significant reduction of the PEP/ET ratio (P < 0.05), peak A (P < 0.05), and isovolumic relaxation time (P < 0.05) along with a normalization of CVI. Conversely, no changes were observed in the placebo-treated group. In conclusion, sHT affects both myocardial structure and contractility. These alterations may be reversed by L-T(4) therapy.

Adult↗

PubMed2001

Ultrasonic myocardial tissue characterization: a methodological review.

Ultrasonic myocardial tissue characterization represents a relatively new diagnostic tool which allows integration of the conventional echocardiographic evaluation, in order to obtain specific textural parameters which reflect the myocardial ultrastructural texture. In particular, through this approach it is possible to obtain two different types of information: the first is static and consists of the absolute myocardial echo intensity that reflects the ultrastructural myocardial changes in different diseases; the second is dynamic and is related to the variations of echo intensity during the cardiac cycle which seem to be linked, even though not linearly, to the intrinsic myocardial contractility. Our research group has extensively applied this methodological approach to different pathophysiological models, in particular to essential hypertension. In the present review the technological evolution of the method and comparison with other research groups' experience with the specific pathophysiological models, are shown and discussed.

Echocardiography↗

PubMed2000

Ultrasonic myocardial textural parameters and midwall left ventricular mechanics in essential arterial hypertension.

BACKGROUND: The evaluation of the systolic left ventricular performance in hypertensive patients presents some problems related to left ventricular hypertrophy (LVH) which alters the ventricular geometry. The videodensitometric textural ultrasonic analysis of hypertensive myocardium has provided evidence of impairment in the cyclic variation of the mean gray level. This might be considered as an index of intrinsic myocardial function. OBJECTIVES: The aim of the present study was to analyse the connection between the midwall fractional shortening and end-systolic stress. The ultrasonic textural parameters in hypertensive patients, arranged in different groups according to the level of LVH and relative wall thickness, were also evaluated. METHODS: A group of age-matched (58 +/- 7 years) male essential hypertensive patients (n = 70) were compared to a group of normotensive and healthy subjects used as controls (n = 32). All subjects performed a conventional 2D-Doppler echocardiography to analyse the left ventricular performance. A quantitative analysis of the echocardiographic digitised imaging was also carried out with the help of a calibrated digitization system in order to calculate the septum and the posterior wall textural parameters. The myocardial mean gray level was calculated to derive the cyclic variation index (CVI). RESULTS: When subjected to a higher meridional end-systolic stress, the hypertensive patients showed a significantly lower midwall fractional shortening than the control patients. The CVI was also significantly lower in the hypertensives group, both for the septum wall (-16.3 +/- 22.8 vs34.7 +/- 15.3%; P < 0.001) and the posterior wall (-5.2 +/- 23.6 vs 38.2 +/- 15.4%; P < 0.001). A significant correlation was found between the midwall fractional shortening (MFS) and the textural parameters, and between these two variables and the end-systolic stress. CONCLUSION: The CVI was found to be a highly sensitive parameter in the identification of abnormal echodensity in essential hypertension. The CVI was significantly lower in patients with concentric hypertrophy in comparison with other left ventricular geometric models. This parameter could be considered as an index of the intrinsic myocardial function, being related, in essential hypertension, to midwall fractional shortening and to end-systolic stress. Journal of Human Hypertension (2000) 14, 9-16.

Blood Pressure↗

PubMed2000

Physiological cyclic variation of the myocardial integrated backscatter signal in athlete's heart.

BACKGROUND: Left ventricular hypertrophy which realizes in athlete's heart could create some problems of acoustic reflection related to the increase of myocytic and not-myocytic elements of the heart. The aim of the present study was to analyze the ultrasonic backscatter myocardial indexes both as peak end-diastolic signal intensity and as its cardiac-cyclic variation in athlete's heart, compared to healthy sedentary controls. METHODS: Two groups of ten subjects each, all males of mean age (31.6+/-3.5), and of comparable weight and height were analyzed: group (A) comprised ten cyclists of good professional level and group (C) included ten healthy subjects acting as controls. A 2D-color Doppler echocardiography with a digital echograph Agilent Technologies (AT) Sonos 5500 was carried out on all subjects in the study for the conventional analysis of the left ventricular mass and function. The ultrasonic myocardial integrated backscatter signal (IBS) was analyzed with an "Acoustic Densitometry" module implemented on an AT echograph. The signal was also sampled with a R.O.I. placed at interventricular septum and at posterior left ventricular wall level. The systo-diastolic variation of the backscatter was also considered as Cyclic Variation Index (CVIibs). RESULTS: The left ventricular mass was significantly higher in athletes in comparison with controls (LVMbs: A: 154.5+/-18.7; C: 101.4+/-12.4; p<0.001). The end diastolic IBS signal did not show significant statistical differences between the two groups. The CVIibs both at septum (A: 30.5+/-5.3; C: 27.2+/-7.3; p<0.002) and posterior wall level (A: 43.7+/-9.1; C: 40.7+/-9.1; p<0.001) though was comparable in both groups. CONCLUSION: The conclusions reached in the present study confirmed the physiology of the left ventricular hypertrophy of the athlete's heart evaluated with an ultrasonic integrated backscatter tissue characterization, in particular through the cyclic variation of integrated backscatter myocardial signal. This finding is probably the expression of a preserved intramural myocardial function in the athlete's heart despite the increase of left ventricular mass induced by physical training.

Adult↗

PubMed2000

Ultrasonic myocardial textural analysis in subclinical hypothyroidism.

BACKGROUND: In subclinical hypothyroidism (sHT), a condition in which impaired hormone synthesis is compensated by thyroid-stimulating hormone (TSH) hypersecretion, previous studies have suggested the presence of disturbances in left ventricular (LV) function. OBJECTIVES: Our goal was to investigate LV structure and function through the combined use of conventional Doppler echocardiography and ultrasonic videodensitometry. METHODS: We studied 16 patients with sHT (aged 32+/-12 [mean +/- SD] years) who had raised TSH levels (> 3.6 mIU/L) but normal levels of free thyroid hormones (free thyroxine [FT(4)] and free triiodothyro-nine [FT(3)]), and 16 carefully age- and sex-matched euthyroid subjects. Transmitral flow Doppler analysis and quantitative analysis of the echocardiographic digitized images were performed in all study subjects. Textural parameters of the septum and posterior wall were obtained as mean gray levels, which were then used to calculate the cyclic variation index (CVI), that is, the percent change in mean gray levels between diastole and systole. RESULTS: Patients with sHT had a significantly higher LV mass index (92 +/- 16 versus 76 +/- 16 g.m(2), P<.01) and isovolumic relaxation time corrected for heart rate (IVRTc) (2.9 +/- 0.6 versus 2.5 +/- 0.6, P<.04) than did controls. On videodensitometry, patients had lower CVIs both for the septum (-5% +/- 22% versus 33% +/- 9%, P<.0001) and the posterior wall (10% +/- 26% versus 49% +/- 18%, P<.0001). IVRTc discriminated only 25% of the patients from the controls, whereas CVI analysis correctly identified 85% of the patients with sHT (P<.002). Furthermore, CVI values were found to be significantly related to serum FT(4) and FT(3) concentrations in a direct fashion, and to serum TSH levels in an inverse fashion. CONCLUSIONS: Subclinical hypothyroidism is associated with changes in videodensitometric myocardial structure. These changes, which are not accurately detected by conventional or Doppler echocardiography, are quantitatively related to loss of thyroid function and could represent an early sign of myocardial damage in hypothyroidism.

Adult↗

PubMed2000

The potential prognostic value of ultrasonic characterization (videodensitometry) of myocardial tissue in essential arterial hypertension.

BACKGROUND: Left ventricular hypertrophy (LVH) and the geometric shape of the left ventricle are well-established important risk factors for cardiovascular morbidity and mortality in the hypertensive population. Videodensitometry is an alternate echocardiographic approach to the study of myocardial structural and functional alterations in essential hypertension. OBJECTIVES: To analyze the behavior of the ultrasonic videodensitometric parameter for various subgroups of a hypertensive population; first according to the severity of LVH (group A, without LVH; group B, with mild-to-moderate LVH; and group C, with severe LVH) and second according to geometric adaptation of left ventricle to pressure-volume overload of essential hypertension (group NG, normal geometry; group CR, concentric remodeling; group CH, concentric hypertrophy; and group EH, eccentric hypertrophy). METHODS: For 70 male, essential hypertensive patients and 32 normotensive healthy subjects matched for age (58 +/- 7 years) and sex as controls (group N) we performed ambulatory blood pressure measurements for the evaluation of 24 h mean systolic and diastolic blood pressures, conventional two-dimensional Doppler echocardiography to evaluate left ventricular performance and left ventricular mass index, and digitization of left ventricular parasternal long-axis echocardiographic images. For regions of interest selected within the septum and the posterior wall, the mean gray levels were calculated at end-systole and end-diastole. The resulting values were used to estimate the percentage cyclic variation index (CVI). RESULTS: The results according to left ventricular mass index were CVI for septum group N 34.7 + 16.3%; group A - 0.18 +/- 16%, group B - 13 +/- 19%, and group C - 22 +/- 12% (P < 0.001); and CVI of posterior wall, group N 38.2 +/- 15.4%, group A -0.75 +/- 16%, group B -16 +/- 16% and group C -16 +/- 13% (P< 0.001). According to left ventricular geometry CVI for septum were group NG 0.6 +/- 24%, group CR 1.9 +/- 17%; group CH - 25.4 +/- 18%, and group EH -17.1 +/- 20% (P < 0.01). CVI of posterior wall were group NH -5.8 + 24%, group CR 6.4 +/- 23%, group CH -29 +/- 20%, group EH -20 +/- 21 (P < 0.01). CONCLUSIONS: Our results demonstrate that subjects with high left ventricular masses and those with concentric hypertrophy, which have the worst prognostic impacts, have the most significant changes in CVI. Furthermore, videodensitometric findings are quite different even among the subgroups with mild-to-moderate left ventricular hypertrophy and eccentric hypertrophy. Therefore this videodensitometric approach could provide some useful information for better definition of cardiovascular risk in hypertension.

Blood Pressure↗

PubMed2000

Microalbuminuria and pulse pressure in hypertensive and atherosclerotic men.

To identify the biological covariates of microalbuminuria (albuminuria >/=15 microg/min) in nondiabetic subjects, brachial blood pressure, echocardiographic left ventricular mass, and other cardiovascular and metabolic parameters were evaluated in 211 untreated males (38 normal controls, 109 uncomplicated stage 1 to 3 essential hypertensives, and 64 patients with clinically stable atherosclerotic peripheral vascular disease either with [n=44] or without [n=20] essential hypertension) with normal cardiac and renal function. Compared with normoalbuminuric subjects, microalbuminuric subjects (n=67) were characterized by higher systolic blood pressure, comparable diastolic blood pressure, and, therefore, wider pulse pressure. Greater prevalence of hypertension, peripheral vascular disease, left ventricular hypertrophy, and reduced HDL cholesterol values further distinguished microalbuminuric from normoalbuminuric subjects in univariate comparisons. The risk of microalbuminuria increased by ascending pulse pressure quintiles in age-corrected logistic regression models, in which pulse pressure was more predictive than systolic pressure and was independent of mean pressure. When microalbuminuric status was regressed against a series of dichotomous (vascular and active smoker status) and continuous (age, pulse and mean pressure, left ventricular mass index, and HDL and LDL cholesterol) variables, only pulse pressure, left ventricular mass index, and smoking status were independent predictors. The association of increased albuminuria with wider pulse pressure, a correlate of the pulsatile hemodynamic load and conduit vessel stiffness as well as an important cardiovascular risk factor, may explain why microalbuminuria predicts cardiovascular events in nondiabetic subjects. The independence from concomitant vascular disease also suggests that wider pulse pressure, rather than representing a simple marker for atherosclerotic disease, influences albuminuria directly.

Adult↗

PubMed1999

Can insulin action induce myocardial texture alterations in essential hypertension?

The prevalence of hyperinsulinemia/insulin resistance in hypertensive individuals, as well as the effects of insulin on myocytic and fibroblastic growth, are well known in both epidemiologic and animal models. To check whether there are any links between ultrasonic myocardial texture parameters and insulin level in essential hypertensives, we compared 18 essential hypertensive men (Group 1, H) with 18 age- and gender-matched healthy controls (Group 2, C) (age, 57 +/- 10 years). For all study subjects we performed ambulatory blood pressure monitoring (ABPM); conventional 2-D Doppler echocardiography for the assessment of the left ventricular mass index (LVMi) and function; quantitative analysis of digitized echocardiographic images for evaluation of cyclic variation (CVI) of mean gray level (MGL) at the septum and posterior wall levels; and 75-g 3-h oral glucose tolerance test (OGTT) for analysis of area under glycemic curve (AUGC, g/min/dL) and insulinemic curve (AUIC, mU/min/mL), as well as serum glucose and insulin peaks. Both the daily mean blood pressure (H: 109 +/- 4.6 v C: 94.6 +/- 4.6, P < .0001) and LVMi (adjusted for body surface) (H: 133 +/- 24 v C: 97 +/- 21 g/m2, P < .0001) were significantly higher in hypertensives. Values for AUIC were significantly higher in hypertensives (10.37 +/- 5.53 v 6.33 +/- 5.28), P < .032); CVI was also significantly higher in group C, for both septum (C: 40.2 +/- 16.9 v H: 15.9 +/- 18.1, P < .0001) and posterior wall (C: 44.5 +/- 19.6 v H: 20 +/- 17.5; P < .0001). There was a significant inverse correlation between AUIC and CVI for both septum (r: -0.57, P < .001) and posterior wall (r: -0.50, P < .002). The significantly higher impairment of myocardial ultrasonic texture and the higher level of the AUIC insulinemia in hypertensives, as well as the significant inverse relationship between CVI and hyperinsulinemia, are our major findings. Hyperinsulinemia/insulin resistance could cause an altered collagen/muscular ratio, which could potentially explain, at least in part, the CVI alterations detected in hypertensive patients.

Adolescent↗