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1.
Am J Cardiol ; 97(10): 1535-7, 2006 May 15.
Article in English | MEDLINE | ID: mdl-16679100

ABSTRACT

Pseudoxanthoma elasticum is an inherited systemic disease of connective tissue with possible cardiac involvement. Nineteen patients with pseudoxanthoma elasticum without a history of cardiac disease were investigated by echocardiography using standard measurements and tissue Doppler imaging. Systolic function was normal, but diastolic parameters were abnormal in 7 patients. Explanations for these abnormalities could be silent myocardial ischemia due to early coronary involvement and/or the direct consequences of ultrastructural defects of the elastic tissue of the heart.


Subject(s)
Pseudoxanthoma Elasticum/diagnostic imaging , Pseudoxanthoma Elasticum/physiopathology , Diastole/physiology , Echocardiography, Doppler , Female , Humans , Male , Middle Aged , Systole/physiology
2.
Am J Cardiol ; 97(6): 912-5, 2006 Mar 15.
Article in English | MEDLINE | ID: mdl-16516601

ABSTRACT

The effects of anabolic androgenic steroids (AASs) on left ventricular (LV) diastolic function in strength-trained athletes are controversial. The main objective of this study was to evaluate the effects of regular AAS administration in bodybuilders using pulsed tissue Doppler imaging (TDI) to evaluate LV relaxation properties. Fifteen male bodybuilders with a history of intensive, long-term strength training and 16 age-matched sedentary controls were recruited. Six of the bodybuilders reported regular use of AASs, and 9 were drug free. To assess LV diastolic function, each subject underwent standard Doppler echocardiography and pulsed TDI. Drug-using bodybuilders exhibited altered LV diastolic filling characterized by a smaller contribution of passive filling to LV filling compared with their drug-free counterparts. TDI measurements indicated that drug-using bodybuilders had smaller peak E(m) than drug-free bodybuilders and sedentary controls, except at the level of the anterior wall, at which peak E(m) was significantly smaller than in drug-free bodybuilders only. The E/E(m) ratio, an index of LV filling pressures, was not affected by strength training or by AAS use. Drug-using bodybuilders exhibited larger LV end-diastolic diameters, volumes, and masses than their drug-free counterparts. However, no difference was found in LV wall thickness between the groups. In conclusion, drug-using bodybuilders showed a decrease in the contribution in LV passive filling to LV filling associated with a decrease in LV relaxation properties. Because no wall thickening was obtained in drug-using bodybuilders, the decrease in LV relaxation properties might have been be due to an alteration in the active properties of the myocardium, but that has yet to be confirmed.


Subject(s)
Anabolic Agents/pharmacology , Echocardiography, Doppler/methods , Heart Ventricles/drug effects , Steroids/pharmacology , Ventricular Function, Left/drug effects , Adult , Blood Pressure/drug effects , Case-Control Studies , Exercise/physiology , Humans , Male , Ventricular Function, Left/physiology
3.
Int J Cardiovasc Imaging ; 21(2-3): 239-47; discussion 249-51, 2005.
Article in English | MEDLINE | ID: mdl-16015435

ABSTRACT

PURPOSE: A dynamic cardiac phantom was used as a reference to compare volumes measured with gated SPECT and 4D echocardiography. MATERIAL AND METHODS: Gated SPECT data were acquired with a standard single-head gamma camera, and the volume reconstructions were carried out using the Mirage software by Segami. 4D echocardiography used a new prototype of rotating scan head to acquire ultrasound images during a cardiac cycle, used to reconstruct the volume deformations as a function of time. End-diastolic volume, end-systolic volume, and ejection fraction were measured using both gated SPECT and 4D echocardiography. RESULTS: The results obtained showed a good correlation between volumes measured with the two modalities, but a slight overestimation of volumes with gated SPECT. The influence of filtering and pixel size parameters on the measured volumes was quantified for gated SPECT, in order to correct the overestimation. CONCLUSION: The agreement between gated SPECT (after correction) and 4D echocardiography confirmed the relevance of the comparisons. This study was an initial step before conducting clinical trials to compare exhaustively left ventricular volumes obtained with the two modalities.


Subject(s)
Cardiac Volume/physiology , Echocardiography, Four-Dimensional , Phantoms, Imaging , Tomography, Emission-Computed, Single-Photon , Cardiac Output/physiology , Heart Ventricles/diagnostic imaging , Humans , Image Processing, Computer-Assisted , Ventricular Function, Left/physiology
4.
Med Sci Sports Exerc ; 36(9): 1507-13, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15354031

ABSTRACT

UNLABELLED: In children and adults, endurance training increases resting stroke volume, mainly as a result of an increase in left ventricular (LV) filling. PURPOSE: To evaluate whether the LV morphologic and functional alterations responsible for this increase in cardiac filling are similar in children and young adults. METHODS: Standard echocardiography (LV morphology and function) and tissue Doppler imaging (LV relaxation properties) were assessed in 10 adult cyclists, 13 age-matched sedentary controls, 12 boy cyclists, and 11 untrained boys. RESULTS: In our endurance-trained adults, LV morphological adaptations included increase in LV internal diameters, wall thickness, and mass. However, effects associated with training on LV morphology were different in children because no true cardiac hypertrophy was observed in our child cyclists compared with age-matched nonactive boys. Effects related training on LV systolic and diastolic function assessed by TDI were similar in boys and men. The LV diastolic function was improved in trained subjects (i.e., increased transmitral early to late filling velocities) as a result of an increase in LV relaxation properties. However, LV filling pressures, estimated from TDI, were similar in trained individuals compared with age-matched controls. CONCLUSION: In both children and adults, an increase in LV relaxation properties and normal LV filling pressures in endurance-trained subjects might be taken as additional indicators for a physiologic or "normal" hypertrophy. However, further investigations are needed to evaluate whether the specific LV morphological adaptation observed in trained-children reflects a blunted trained-induced cardiac hypertrophy before puberty.


Subject(s)
Bicycling/physiology , Ventricular Function, Left , Adult , Case-Control Studies , Child , Echocardiography , France , Humans
5.
Article in English | MEDLINE | ID: mdl-15217240

ABSTRACT

A fast continuous rotating ultrasound scan-head transducer was used to perform three-dimensional (3-D) echocardiography with 2-D images acquired during a single cardiac cycle. The 3-D images were reconstructed by interpolating 2-D data acquired with the probe. Two experiments were carried out to validate the image reconstructions. A dynamic cardiac phantom was used as a known reference to compare the minimal and maximal volumes estimated manually on the reconstructed 3-D images. The left ventricle (LV) volume of 30 healthy volunteers also were estimated using a semiautomatic ellipse approach and compared to measurements obtained with standard 2-D examination. Results showed a good agreement between 3-D and reference measurements.


Subject(s)
Algorithms , Echocardiography, Three-Dimensional/instrumentation , Echocardiography, Three-Dimensional/methods , Equipment Failure Analysis , Heart Ventricles/diagnostic imaging , Image Enhancement/instrumentation , Image Enhancement/methods , Transducers , Humans , Phantoms, Imaging , Reproducibility of Results , Rotation , Sensitivity and Specificity , Stroke Volume , Time Factors
6.
Med Sci Sports Exerc ; 34(12): 1951-7, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12471301

ABSTRACT

UNLABELLED: A transient increase in left ventricular emptying has been reported in adults during the early recovery from submaximal upright exercise. PURPOSE: To investigate whether this "overshoot" occurs also after maximal exercise, and whether it is an age-related phenomenon. METHODS: Ten healthy young men (mean age: 22.5 +/- 1.5 yr) and 17 healthy prepubertal boys (11.5 +/- 0.8 yr) performed an upright cycle test until exhaustion. Respiratory gas exchange, heart rate, left ventricular dimensions (two-dimensional echocardiography method) as well as blood pressures (manual sphygmomanometry) were assessed and systemic vascular resistances were calculated at rest, during the final minute of the test, and during a 10-min recovery period. RESULTS: An improvement of cardiac emptying, characterized by a decrease in left ventricular end-systolic diameter, was observed in adults only. Moreover, during the first minute of recovery, a larger decrease in heart rate -21.8 +/- 7.6% and -13.7 +/- 6.3 beat.min, respectively, in children and adults, P < 0.01) and a larger increase in systemic vascular resistance (+24.1 +/- 18.2% and +6.4 +/- 12.6%, P < 0.05) were observed in the boys rather than in the adults. CONCLUSION: Our results suggest that a higher increase in cardiac afterload and a more prominent decrease in heart rate may be responsible in part for the absence of cardiac overshoot in children.


Subject(s)
Exercise/physiology , Recovery of Function/physiology , Ventricular Function, Left/physiology , Ventricular Function , Adult , Age Factors , Blood Pressure/physiology , Body Mass Index , Body Surface Area , Child , Diastole/physiology , Echocardiography , Exercise Test , Heart Rate/physiology , Heart Ventricles/diagnostic imaging , Humans , Male , Oxygen Consumption/physiology , Reference Values , Stroke Volume/physiology , Systole/physiology , Time Factors , Vascular Resistance/physiology
7.
J Am Soc Echocardiogr ; 15(6): 593-600, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12050600

ABSTRACT

The evaluation of left ventricular function by noninvasive methods is still a major problem in cardiology. Two-dimensional echocardiography requires mental reconstruction of the heart by the physician and is always based on approximation of heart shapes and volumes. Three-dimensional echocardiography is promising but has rhythmic and function constraints because of the acquisition during many cardiac cycles. This article reports a study carried out to validate a new 4-dimensional echocardiography method. With the use of a classical phased-array sensor with a fast rotating motorized motion and a standard ultrasound system, many slices at different angulations are obtained in a single cardiac cycle. After manual endocardial delineation and computation, a representation of the left ventricle (beating heart) and a volume quantification are obtained at each instant of the cardiac cycle. This method has been tested on 11 healthy volunteers and the results are in agreement with those obtained with standard 2-dimensional echocardiography. Because of its simplicity of operation and short time acquisition, this new imaging modality is highly valuable in left ventricle evaluation, even if further studies on pathologic hearts need to be performed.


Subject(s)
Echocardiography, Four-Dimensional , Heart Ventricles/diagnostic imaging , Ventricular Function, Left/physiology , Adult , Diastole/physiology , Echocardiography , Humans , Image Processing, Computer-Assisted , Observer Variation , Stroke Volume/physiology , Systole/physiology
8.
Med Sci Sports Exerc ; 34(3): 456-63, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11880810

ABSTRACT

PURPOSE: Stroke volume response to exercise depends on changes in cardiac filling, intrinsic myocardial contractility, and left ventricular afterload. The purpose of this study was to compare these responses during an upright cycle test performed until exhaustion in children and adults. METHODS: Stroke volume, cardiac output (Doppler echocardiography), left ventricular dimensions (two-dimensional and time-movement echocardiography), as well as arterial pressure and systemic vascular resistance (SVR) were assessed in 17 boys (mean age, 11.7 +/- 0.6 yr) and 23 young adult men (mean age, 21.2 +/- 2.7 yr) having a similar aerobic potential. All variables were measured at the end of the resting period, during the final minute of each workload, and during the last minute of the test. RESULTS: No significant differences were obtained for stroke volume, cardiac output, and left ventricular dimensions when they were scaled to body surface area at rest and whatever the exercise intensity. However, arteriovenous oxygen uptake was higher and the SVR lower in the adults than in the children. CONCLUSION: The patterns of stroke volume, as well as its underlying mechanisms, were not age-related during an upright maximal exercise test. However, other studies are required to understand further the effect of pubertal status on the peripheral cardiovascular system.


Subject(s)
Adaptation, Physiological , Exercise/physiology , Heart Rate , Stroke Volume , Ventricular Function, Left , Adult , Child , Echocardiography, Doppler , Humans , Male , Myocardial Contraction , Oxygen Consumption , Pulmonary Gas Exchange
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