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C Giusti

Publications and source records attributed to C Giusti.

At least 19 recordsLinked to original sources

Simultaneous dobutamine stress echocardiography and dobutamine scintigraphy (99mTc-MIBI-SPET) for assessment of coronary artery disease.

BACKGROUND: Simultaneous dobutamine stress echocardiography (DSE) and 99Tc-MIBI-SPET (DMS) for the evaluation of the presence and the extent of coronary artery disease (CAD) were assessed for a head to head comparison regarding the diagnostic acuracy of the two rests. METHODS AND RESULTS: Forty-five consecutive patients (33 males and 12 females: 53 +/- 6.8 yr.) underwent exercise electrocardiography and simultaneous dobutamine stress echocardiography and MIBI-SPET imaging. Coronary angiography was performed in all patients (significant coronary stenosis > 50%). On the basis of the results of exercise electrocardiogram the pre-test probability for coronary artery disease (Diamond's algorithm) was low (45.6 +/- 12.7%). The overall specificity, sensitivity and predictive accuracy of Echo-dobutamine stress test for diagnosis of the presence or absence of CAD were: specificity 82%, sensitivity 76%, diagnostic accuracy 80%, positive predictive value 90%, negative predictive value 40%. The overall specificity, sensitivity and predictive accuracy of MIBI-SPET-dobutamine test for diagnosis of the presence or absence of CAD were: specificity 86%, sensitivity 87%, diagnostic accuracy 84%, positive predictive value 97%, negative predictive value 54%. MIBI-SPET-dobutamine test showed a significantly higher sensitivity in comparison with ECHO-dobutamine test (P < 0.05). CONCLUSION: Both noninvasive methods for the detection of CAD showed a good diagnostic accuracy. Nevertheless the SPET model showed a higher sensitivity in comparison with DSE model, essentially in the presence of a lower extent of CAD and during submaximal test.

Cardiotonic Agents

Left ventricular function during exercise in athletes and in sedentary men.

Aim of this study was to evaluate left ventricular function during exercise in 10 male elite runners and in 10 sedentary males. End-diastolic (EDV) and end-systolic volume (ESV), left ventricular ejection fraction (EF), early peak transmitral flow velocity (peak E), time-velocity integral of mitral inflow (m-TVI); mitral cross sectional area (m-CSA); mitral stroke volume (SV), and cardiac output (CO) were measured by echo-Doppler. We simultaneously analyzed: VO2max by spirometric method, mean arterial blood pressure (MAP) by sphygmomanometer, and heart rate (HR) by ECG. The parameters were measured under basal conditions (level 1), at 50% of maximal aerobic capacity (level 2), at peak of exercise (level 3) and during recovery. Ejection fraction in athletes increased significantly at peak of exercise through Frank-Starling mechanism. Stroke volume and cardiac output increased significantly in athletes at peak of exercise. Left ventricular diastolic function was superior in athletes versus controls: in fact, higher peak E in athletes enhanced early diastolic ventricular filling. Therefore, the athletes showed complex cardiovascular adjustments induced by training, which allowed an higher peak working power, a greater cardiac output, and VO2max when compared with an untrained control population.

Adult

The effect of cigarette-smoking on cardiovascular risk factors: a study of monozygotic twins discordant for smoking.

The association of cigarette smoking with the development of occlusive vascular disease is firmly established. Unfavourable changes in a series of variables held independent risk factors for the development of vascular lesions (HDL-cholesterol, haematocrit, white blood cell count, fibrinogen and plasminogen activator inhibitor-1 (PAI-1)) are thought to be directly influenced by cigarette smoking. However, the role played by the genotype in the effect of smoking on the above parameters has not been investigated. To control the genotype, we studied the relationship between cigarette smoking and a series of cardiovascular risk factors in 27 monozygotic twin pairs (7 male and 20 female pairs, mean age +/- SD: 47.4 +/- 12.9 yrs) with a life-long discordance for smoking. Smoking twins had a life-long dose of smoking (Brickman index) of 287.3 +/- 241.5. Body mass index, blood pressure, haematocrit, haemoglobin and red blood cell counts, total cholesterol levels and the acute phase reactants alpha 1-acid glycoprotein and C-reactive protein were similar in smokers and non-smokers. Triglyceride was higher by 12.6% (9.5-35%, 95% confidence interval, p = 0.02) and HDL-cholesterol lower by 7.5% (0.2-15%, p = 0.04) in the smoking co-twins, who also had 8.4% (-0.2-17%, p = 0.06) higher white blood cell counts and 4.1% (1.2-7%, p < 0.01) larger mean platelet volume. There was no significant difference in clottable fibrinogen (by two methods) or in the activity of plasminogen activator inhibitor-1 between the two groups, nor was the within-pair difference in these parameters related to the smoking dose. Echo-doppler examination of the carotid arteries of 24 twin pairs showed mostly minor atherosclerotic lesions in 46% and 42% of the smoking and non-smoking co-twins. After adjustment for age, systolic blood pressure and platelet count and volume were the only variables significantly associated to the presence of vascular lesions. Cigarette smoking is associated with an atherogenic lipid profile and with changes in platelets and white cells potentially reflecting endothelial cell damage. When controlling the genotype, fibrinogen and PAI-1 activity levels did not seem directly influenced by cigarette smoking.

Adult

Informed versus randomised consent to clinical trials.

We compared different procedures for seeking consent to participate in a sham randomised clinical trial and assessed whether refusal is affected by awareness of the severity of outlook. 2035 healthy subjects aged between 20 and 80 years, who visited a scientific exhibition, were enrolled in a hypothetical trial of experimental versus standard therapy, and randomly assigned to groups asked for conventional informed consent or prerandomisation consent. There were four study groups: one-sided informed consent for randomisation (subjects who refused would receive standard treatment); two-sided informed consent for randomisation (subjects who refused could choose between standard and experimental treatment); randomised consent to experimental treatment (subjects who refused would receive standard treatment); and randomised consent to standard treatment (subjects who refused would receive experimental treatment). The refusal rates were 16.2%, 19.9%, 12.1%, and 49.2%, respectively. The perceived severity of the simulated disease affected the refusal rate: the worse the outlook, the lower the refusal rate for informed consent or for consent after randomisation to new treatment, and the higher the refusal rate for consent after randomisation to standard treatment. The prerandomisation design seems to be efficient in a one-sided clinical scenario (eg, a trial of a new drug that would not be given outside the trial) because the refusal rate was substantially lower for prerandomisation to the new treatment than for conventional one-sided informed consent. However, in a two-sided clinical scenario (eg, a trial comparing similar treatments) the prerandomisation design is potentially highly inefficient; the refusal rate was much higher for prerandomisation to standard treatment than for conventional two-sided informed consent.

Adult

Increased echodensity of myocardial wall in the diabetic heart: an ultrasound tissue characterization study.

OBJECTIVES: We sought to characterize myocardial echodensity in asymptomatic patients with insulin-dependent diabetes and normal conventional two-dimensional echocardiographic findings to determine whether ultrasound tissue characterization can detect ultrastructural changes in myocardium, such as an increase in collagen content. BACKGROUND: Fibrosis alters the acoustic properties of the heart in animals and humans, and these changes are detectable by cardiac tissue characterization with ultrasound. Early changes detected in the diabetic heart include increased interstitial collagen deposition. METHODS: Using two-dimensional echocardiography, we evaluated 26 asymptomatic patients with insulin-dependent diabetes with normal regional and global rest function, and 17 age- and gender-matched control subjects. By selection, all diabetic patients were normotensive and had negative maximal exercise stress test results to avoid the confounding effects of hypertension and coronary artery disease. Using an echocardiographic instrument implemented at the Institute of Clinical Physiology, we performed an on-line radiofrequency analysis to obtain quantitative operator-independent measurements of the integrated back-scatter signal of the ventricular septum and posterior wall. The integrated values of the radiofrequency signal from the myocardial wall were normalized for those from the pericardial interface and were expressed as percentages (integrated backscatter index). RESULTS: Diabetic patients showed a significant increase in myocardial echodensity both in the septum ([mean +/- SD] 36.6 +/- 8.1 vs. 23.6 +/- 4.4, p < 0.0001) and posterior wall (21.2 +/- 5.3 vs. 18.4 +/- 3.7, p < 0.001). By individual patient analysis, 17 patients exceeded the 95% confidence limits for normal myocardial echocardiographic reflectivity found in normal subjects, and only 3 had a relatively abnormal transmitral Doppler filling pattern (E/A ratio), mainly consisting of an abnormally increased late peak flow velocity (65% vs. 11%, p < 0.001). The increased myocardial intensity was similar in patients with (n = 16) and without (n = 10) noncardiac complications, such as retinopathy or nephropathy (37.5 +/- 7.9% vs. 35.0 +/- 8.3%, p = 0.35). CONCLUSIONS: Abnormally increased myocardial echodensity, possibly related to collagen deposition, can be detected in asymptomatic diabetic patients with normal rest function. Theoretically, this finding might be considered a very early preclinical alteration potentially related to subsequent development of diabetic cardiomyopathy.

Adult

Evaluation of maximal left ventricular performance in elite bicyclists.

Aim of this work was to study in a group of elite cyclists, undergoing laboratory testing, the trend of the left ventricular systolic and diastolic function, echocardiographically and Doppler derived, simultaneously with the evaluation of ergospirometric parameters during maximal exercise. We studied a group of male subjects, consisting of 10 professional elite bicyclists (mean age: 25.1 +/- 3.2 years) during competitive activity (VO2/kg max: 78.5 +/- 7.7 ml.kg.min-1). The maximal exercise test, conducted with Wind Loaded Simulator for optimisation of ergometric capacity, showed, at the end of exercise, at a speed of 49.2 +/- 2.4 km/h, a VO2max of 5365 +/- 543.4 ml/min, with a calculated Cardiac Output (CO) of 19.3 +/- 3.7 l/min. A linear regression relationship was found between VO2max and CO (r = 0.84; p < 0.0001) as well as between VO2max and maximal reached speed (r = 0.97; p < 0.0001). During the aerobic period a slight but significant increase in End Diastolic Volume (EDV) was observed due to the greater venous return from exercising muscles. At stop, in anaerobic period, the EDV remained substantially constant. Ejection Fraction (EF) also increased during exercise through the Frank-Starling mechanism activation. The slight, but not significant, increase in EF at stop level may be explained by an activation of homeometric control of contractility with a sympathetic modulation on myocardial fibres. The early diastolic mitral flow velocity (Peak E) increased significantly during exercise, in comparison with basal upright values. The left ventricular diastolic compliance observed in athletes permits a good left ventricular filling, particularly in early diastolic phase; this allows an excellent left ventricular systolic performance. Based on echocardiography and pulsed Doppler measurements, calculated cardiac output is underestimated by approximately 20%.

Adult

[The request for consent in clinical research: a randomized study in healthy subjects].

To compare two strategies of consent requirement (classical informed consent and randomised consent according to Zelen), the Clinical Data Elaboration Centre of South Italy, within the special project Clinical Application of Oncological Research of the National Research Council of Italy (CNR-ACRO) invited healthy people visiting the 7th edition of the scientific exhibition "Futuro Remoto" to simulate of being ill and receiving the offer of entering a clinical trial. Within informed consent strategy patients are asked to agree to the randomisation process, while, in the randomised consent, randomised treatment assignment is performed before consent requirement and patients should agree directly to the assigned therapy. Major aims of the study were (a) to compare the strategies in terms of refusal rate to a hypothetical clinical trial, and (b) to estimate whether severity of prognosis affected subjects' decision. 3,217 visiting people participated to the simulation; they were prevalently young, males and with a high level of school education. The study was performed in two different scenarios. In the first one, with one choice option, subject refusing consent could receive standard therapy only; refusal rate was 16% after informed consent and 13.4% after randomised consent (for experimental therapy). In the other scenario, with two choice options, subjects refusing consent could choose the preferred therapy; refusal rate was 20.6% after informed consent, 48.1% after randomised consent (for standard therapy) and 13.4% after randomised consent (for experimental therapy).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent

[Ultrasonic evaluation of early atherosclerotic damage in patients with type 1 diabetes mellitus].

UNLABELLED: The aim of this study was to evaluate the influence of metabolic control on the development of atherosclerotic lesions in type 1 insulin-dependent diabetic patients (IDDM). MATERIALS AND METHODS: Twenty-eight well controlled IDDM patients, without known risk factors or clinical evidence of cardiovascular disease, together with 28 age-matched healthy controls spontaneously underwent high-resolution echographic evaluation of carotid femoral arteries. A global score of atherosclerotic damage as been assigned to the four investigated vessels on the basis of 1-6 scale, which takes into account most important ultrasound atherosclerotic lesion found in every artery. RESULTS: Diabetic and healthy controls differed significantly as regard to medio-intimal carotid thickness (p < 0.001), but were similar as for score of atherosclerotic damage. CONCLUSIONS: Our results suggest that, in spite of a carotid wall medio-intimal thickness more pronounced in IDDM patients, well controlled IDDM is associated with atherosclerotic damage almost identical to that of healthy age-matched controls.

Adolescent

[Cardiovascular effects of autonomic neuropathy in insulin-dependent diabetes mellitus].

The present study was designed to evaluate whether autonomic diabetic neuropathy is a marker of severe cardiovascular disease. We recruited three groups of 12 patients each with the same age, sex and body weight distribution: Group DAN + (diabetics with neuropathy), Group DAN- (diabetics without neuropathy) and Group C (healthy control group). The patients underwent two-dimensional color Doppler echocardiography and maximal electrocardiographic exercise test by cycloergometer (multistage program with 25 W increments 3 min steps). Cardiovascular autonomic function was evaluated by Ewing's tests (heart rate and blood pressure measurement during lying to standing, deep breathing, handgrip isometric stress test and Valsalva manoeuvre). Heart rate and blood pressure proved to be significantly higher in the Group DAN+, than in the other groups, either at baseline or during stress test. Only 33% of DAN+ patients proved to reach 100 W during stress test, compared to 82% of DAN- and 87% of control subjects. No DAN+ patients reached 125 W, compared with 45% of DAN- and 58% of Group C patients. Echocardiographic examination showed normal left ventricular systolic function in all groups, without any significant difference in ventricular dimensions, and impaired left ventricular diastolic function in DAN+ patients, compared to Group C subjects (peak E 66.75 +/- 8.36 vs 73.49 +/- 12.53 cm/s; peak A 72.1 +/- 13.42 vs 59.75 +/- 13.26 cm/s; E/A 0.84 +/- 0.21 vs 1.38 +/- 0.15 and isovolumetric relaxation time 101 +/- 21 vs 70 +/- 17 ms). Our data suggest that diabetic autonomic neuropathy is a marker of reduced exercise tolerance and of diastolic left ventricular dysfunction.

Adult

Forearm blood flow reserve and cardiac and renal indexes of pressure load in normotensive and hypertensive individuals.

In response to hypertension, arterioles remodel their structure, the heart develops myocardial hypertrophy, and the kidney reduces creatinine clearance and increases albuminuria. To better understand the interrelations among the target organs involved in hypertension, we evaluated minimal forearm vascular resistances--a hemodynamic index of arteriolar structure derived from mean blood pressure and maximal postischemic forearm blood flow--the echocardiographic indexes of cardiac structure, and urinary albumin excretion and creatinine clearance in 29 male mild to moderate non-macroalbuminuric essential hypertensive patients on no drugs and 11 age- and sex-matched normotensive control subjects. Minimal forearm resistances were elevated in hypertensive patients and correlated with left ventricular mass, wall thickness, and mean arterial pressure. Patients with abnormal minimal forearm resistances (2 SD above normal) were characterized by higher pressure, greater wall thickness, lower creatinine clearance, and higher albumin excretion, suggesting that maximal forearm flow capacity does relate to the hemodynamic load exerted on both the kidney and heart. However, the correlation with cardiac structure and mean arterial pressure explained only part of the variability of minimal forearm resistances. Furthermore, no correlation among these parameters was found when hypertensive patients were evaluated separately from normotensive subjects, possibly because of heterogeneous factors active on arteriolar structure and unrelated to the pressor load. Overall, the data suggest that the development of abnormal minimal forearm resistances in the course of the hypertensive process is related to the pressor load, but its details need further understanding.

Adult

[Therapy of arterial hypertension associated with acute stroke. Current trends and problems].

Acute stroke may cause hypertension and actually available devices for non-invasive blood pressure monitoring make it possible to study short-term variability of pressure in this condition, in order to settle a more rational diagnostic and therapeutic approach. In our experience blood pressure variability has shown to be greater in thrombo-embolic, than haemorrhagic stroke. This outcome contributes to explain literature disagreement on benefits of antihypertensive therapy and suggests the need for blood pressure monitoring in every trial, that wants to evaluate with satisfactory reliability the antihypertensive treatment in ischaemic stroke. As to antihypertensive drugs to be used in stroke patients, we prefer antiadrenergics, because hypertension in this clinical condition is due to adrenergic overactivity. Our preliminary experience with a centrally acting antiadrenergic drug (clonidine) has shown its ability not only to reduce blood pressure, but also blood pressure variability in ischaemic stroke.

Acute Disease

Left ventricular performance and ultrasonic myocardial quantitative reflectivity in endurance senior athletes: an echocardiographic study.

Young elite athletes often show left ventricular hypertrophy, but normal values of quantitatively evaluated myocardial wall reflectivity. The aim of this study is to assess the acoustic pattern of ventricular wall reflectivity, as well as of systolic and diastolic function, in older endurance runners with increased left ventricular mass. For this purpose, 12 elite, senior isotonic athletes in full training and 11 normal, age-matched controls with sedentary life styles were studied. The following parameters were measured with a commercially available 2D echo-Doppler machine: end-diastolic diameter, diastolic septum thickness, left ventricular mass index, ejection fraction (by Teicholtz rule); peak E, peak A, E/A ratio, acceleration and deceleration time of mitral inflow velocity and isovolumic relaxation time. On-line radio frequency analysis was also performed to obtain quantitative operator-independent measurements of the integrated backscatter signal of the ventricular septum and the posterior wall. The integrated values of the radiofrequency signals were normalized for the pericardial interface and expressed in percent (% 2D-IB). In spite of the greater left ventricular mass in athletes versus normal controls (319 +/- 81 vs 225 +/- 63 g.m-2, P < 0.0005), there were no significant intergroup differences as regards end-diastolic diameter (50.7 +/- 5.1 vs 48.1 +/- 5.2 mm, P = ns), ejection fraction (75.5 +/- 9.3 vs 71.8 +/- 9.1%, P = ns), and 2D-IB of septum (22.2 +/- 6.9 vs 22.4 +/- 7.0, P = ns) and posterior wall (12.5 +/- 5.6 vs 13.1 +/- 2.8, P = ns).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged

Microalbuminuria is a marker of left ventricular hypertrophy but not hyperinsulinemia in nondiabetic atherosclerotic patients.

Microalbuminuria predicts cardiovascular events in diabetic and nondiabetic patients. For a better understanding of the physiopathological importance of microalbuminuria in atherosclerotic disease, we evaluated the relation between urinary albumin excretion and arterial blood pressure, left ventricular mass, insulin, and lipid levels. The studies were conducted in patients with atherosclerotic peripheral vascular disease. Urinary albumin excretion (studied by nephelometry; an average of triplicate collections from 8 PM to 8 AM), causal blood pressure, echocardiographic left ventricular mass index and wall thickness, plasma immunoreactive insulin and C-peptide (both basally and after a 75-g oral glucose load), blood lipids, and fibrinogen were studied in eight normal subjects and 20 nonobese, nondiabetic male patients with angiographically documented atherosclerotic peripheral vascular disease and preserved renal function, 12 of whom were either hypertensive or on antihypertensive treatment. Eight patients were microalbuminuric (urinary albumin > 20 micrograms/min) and 12 were not. Ankle-arm index and calf and foot transcutaneous oxygen tension were reduced in comparison with normal control subjects but superimposable between the two patient groups to indicate a comparable clinical progression of the vascular disease. In the microalbuminuric subjects, left ventricular mass index was greater, interventricular septum was thicker, and cardiac hypertrophy was more frequent than in nonmicroalbuminuric patients. The prevalence of hypertension tended to be greater and systolic blood pressure values were higher in the presence of microalbuminuria. Overall, a highly significant relation existed between urinary albumin excretion and left ventricular mass. Systolic blood pressure was greater and a history of arterial hypertension was more frequent among microalbuminurics, whereas diastolic blood pressure values showed a statistically significant correlation with both variables.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral

Dilation of venous vessels at the splenic hilum in normal sized spleens as an indication of pathologic splenic involvement: preliminary results.

Twelve hundred patients without liver or heart disease, having a normal sized spleen without focal lesions, were examined by ultrasonography to measure the inner diameter of the splenic vein in relation to possible current or recent recovery from pathologic processes. SVD was measured at the hilum of the spleen with the patients supine. Ten of the patients in whom dilation of the SVD was found, together with a group of healthy controls (25), were subsequently studied with a duplex Doppler analysis to measure the venous outflow from the spleen. The results showed 1,175 spleens (98%) with SVD at the hilum of < 8 mm and 25 spleens (2%) with SVD of > 8 mm. Twenty-three of 25 patients (92%) with enlarged SVD had recent histories of hematopoietic or infectious diseases. Ten of 23 patients with enlarged SVD were studied further with a Doppler analysis. They demonstrated a rapid splenic blood flow with maximum flow velocities ranging from 14 to 27 cm/sec and high outflow volumes (from 430 to 1,227 ml/min, averaging 786 ml/min +/- 266), both significantly increased in comparison with controls (outflow volume from 200 to 355 ml/min, averaging 274 +/- 40; P < 0.0001). We conclude that dilation of the SVD accompanied by an increased intrasplenic blood flow volume without splenic enlargement would indicate a state of increased perfusion of splenic tissue associated with an immune response, reflecting reaction of the spleen to disease.

Adolescent

[Cardiovascular effects of amitriptyline in therapeutic dosages. Echocardiographic study].

The authors studied the cardiovascular effects of amitriptyline at therapeutic plasma concentrations in 15 depressed patients (6 M. 9 F.) without cardiovascular disease both before treatment and after six months of therapy. The cardiovascular effects were evaluated by means of electrocardiographic and 2D-echocardiographic examinations in basal conditions and after hand-grip stress test. The effects of isometric hand-grip exercise (IHG) on left ventricular size and performance were studied non invasively in all patients at rest and after 3 min. of IHG at 30% of maximum contraction. Left ventricular internal diameter was measured at end-diastole and end-systole on LV echograms, and blood pressure was measured by sphygmomanometer. Our data confirmed the depressant effect of amitriptyline even on healthy myocardium, an effect that becomes manifest only at handgrip stress with a significant reduction of ejection fraction (form 70.6 to 66.4%; p < 0.001), while ECG and arterial blood pressure did not change throughout the study. This goes to show that treatment with tricyclic antidepressants always has a latent depressant effect on myocardial contractility that becomes clinically evident under stress, as well as in subjects with heart disease and in the elderly. Hence the need to monitor left ventricular function, as well as ECG and blood pressure, and to exercise great caution in prescribing tricyclic antidepressants to subjects with a history of myocardial failure.

Aged

[The effect of physical exercise on the response to exertion in the elderly].

BACKGROUND: A decrease in adaptation to exertion has been observed as age progresses. Although this decline may also be affected by factors such as health conditions and age, physical inactivity related to sedentary behaviour plays a dominant role. METHODS: In order to evaluate the influence of physical activity on cardiovascular response to exertion in the elderly, 4 groups of 22 subjects each were submitted to maximal electrocardiographic exercise test on a cycloergometer (multistage program with 30 Watts x 3 min. steps). All subjects were male. The composition of the groups was as follows: 1) veteran long distance runners (mean age: 71 +/- 5.4); 2) sedentary veterans (mean age: 69.8 +/- 3.9); 3) young long distance runners (mean age: 25.4 +/- 4.3); 4) sedentary young adults (mean age: 25.8 +/- 3.9). The endurance athletes, well fitted to competition, had been practicing sport activity for at least 3 years. RESULTS: Heart rate, arterial systolic and diastolic blood pressure were recorded; mean blood pressure and double product were calculated at baseline and at the climax of the stress test; furthermore, total and maximal watts were recorded. For each of the parameters, Student's t test for non-paired observations were used to evaluate statistical differences amongst the four groups. The most interesting result arises in the comparison between veteran long distance runners and sedentary young adults: between the two groups no statistically significant differences in workload, expressed as total watts (1649.55 +/- 296.32 vs 1650.00 +/- 446.32; p = NS) and maximal watts (175.91 +/- 19.19 vs 173.18 +/- 24.38; p = N.S.), were observed. On the contrary, highly significant differences in both total (p < 0.01) and maximal (p < 0.01) watts were noticed by comparing long distance runners and sedentary subjects of the same age. CONCLUSIONS: These data support the hypothesis that the progressive reduction in physical activity, which is usually observed in aging, is the major determinant of exercise deconditioning in the elderly.

Adolescent

Suitability of Doppler echocardiography for the assessment of right heart hemodynamics after De Vega tricuspid annuloplasty.

Cardiac Doppler Echocardiography is a suitable method for to evaluating right heart hemodynamics. However, the surgical correction of tricuspid valve annuloplasty changes valve geometry and might possibly lead to a technical obstacle to this estimation. The accuracy of Doppler echocardiography in the assessment of tricuspid regurgitation and systolic pulmonary pressure in patients who had undergone De Vega annuloplasty was evaluated in this study. Ten patients (9 females and 1 male), mean age 55.7 +/- 7.8 years, who had a previous De Vega annuloplasty for the treatment of tricuspid regurgitation due to a severe mitral stenosis, underwent a Doppler echocardiography study and, within two hours, right heart catheterization for a direct comparison of parameters calculated by different methods. Right ventricular-atrial maximal pressure gradient was found to be 32.6 +/- 11.07 mmHg by Doppler and 31.4 +/- 11.07 mmHg by catheterization. Pulmonary systolic pressure was 42.6 +/- 9.1 mmHg at Doppler and 39.1 +/- 11.3 mmHg at catheterization, with a highly significant correlation between the 2 techniques (r = 0.98%, p < 0.01). With semiquantitative Doppler evaluation 10 patients showed tricuspid insufficiency, which was mild in 8 and medium in 2. At catheterization all patients were found to have mild tricuspid insufficiency. Cardiac Doppler seems a reliable method in the evaluation of tricuspid regurgitation and of pulmonary systolic pressure even in patients who underwent De Vega annuloplasty.

Blood Pressure

Normal ultrasonic myocardial reflectivity in athletes with increased left ventricular mass. A tissue characterization study.

BACKGROUND: Ultrasonic integrated backscatter of myocardial walls is directly related to the morphometrically evaluated collagen content. The integrated backscatter is also increased in hypertrophic cardiomyopathy, probably because of fiber disarray. The purpose of this study was to investigate myocardial tissue reflectivity in subjects with physiological hypertrophy caused by intense physical training and to assess the relation between the acoustic properties of myocardial tissue and left ventricular wall thickness assessed by conventional two-dimensional echocardiography. METHODS AND RESULTS: Twenty-four young male athletes (14 professional cyclists and 10 weight lifters, all in full agonistic activity) were studied together with 10 normal age-matched controls with sedentary life. By means of a commercially available two-dimensional echocardiograph, standard measurements were obtained according to the recommendations of the American Society of Echocardiography. With a prototype implemented in our Institute, an on-line radiofrequency analysis of ultrasound signals was also performed to obtain quantitative operator-independent measurements of the integrated backscatter of the myocardial walls. The integrated values of the radiofrequency signal were normalized for the pericardial interface and expressed in percent integrated backscatter (%IB). Compared with control subjects, athletes showed greater thickness values of septum (controls, 9 +/- 1; cyclists, 14 +/- 2; weight lifters, 15 +/- 1 mm, mean +/- SD; p less than 0.01) and posterior wall (9 +/- 1, 12 +/- 2, and 12 +/- 1 mm, respectively; p less than 0.01) but similar values of %IB for both septum (23 +/- 4%, 21 +/- 7%, and 23 +/- 8%, p = NS) and posterior wall (10 +/- 2%, 9 +/- 2%, and 11 +/- 2%, p = NS). In athletes, no correlation was found between septal and posterior wall thickness and the corresponding regional myocardial reflectivity (r = 0.23, p = NS and r = 0.01, p = NS, respectively). Furthermore, we compared the quantitative ultrasonic data between two subsets of 10 athletes and 10 patients with hypertrophic cardiomyopathy and similar degrees of septal thickness (16 +/- 1 versus 17 +/- 1 mm, respectively, p = NS). Septal and posterior wall %IB results were significantly higher in patients with hypertrophic cardiomyopathy (53 +/- 13% and 36 +/- 9%, respectively) than in athletes (21 +/- 7% and 10 +/- 3%, respectively; p less than 0.01 for both). CONCLUSIONS: We conclude that 1) endurance athletes show a normal pattern of quantitatively assessed ultrasonic backscatter despite of a marked left ventricular hypertrophy and 2) athletes and patients with hypertrophic cardiomyopathy and similar degrees of myocardial wall thickness can be differentiated on the basis of quantitative analysis of backscattered signal.

Adult