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Biomedical subjects

C Giusti

Publications and source records attributed to C Giusti.

At least 37 records · Page 2Linked to original sources
PubMed1994

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↗
PubMed1994

[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↗
PubMed1993

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↗
PubMed1993

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↗
PubMed1993

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↗
PubMed1993

[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↗
PubMed1993

[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↗
PubMed1993

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↗
PubMed1992

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↗
PubMed1991

Twenty-four-hour activity of felodipine extended release in chronic stable angina pectoris.

To investigate the antiischemic efficacy and duration of action of the dihydropyridine calcium antagonist felodipine, 15 patients with stable exertional angina were enrolled in a double-blind, crossover study comparing 2 doses (5 and 10 mg) of felodipine extended release (ER) and placebo given once daily for 1 week. Bicycle exercise tests were repeated at the end of each treatment period 4 and 24 hours after dosing. Four hours after dosing with both felodipine doses, only 5 patients discontinued the exercise test because of greater than 2 mm of ST-segment depression, whereas 10 continued until exhaustion (p less than 0.01 vs placebo). Compared with placebo, total exercise time was increased by 19% (p less than 0.001), with no difference between doses. After 24 hours, exercise duration was prolonged up to physical exhaustion in 6 patients taking felodipine 10 mg (p less than 0.05 vs both placebo and felodipine 5 mg); moreover, 11 patients taking 10 mg and 5 taking 5 mg increased time to 1 mm of ST depression greater than or equal to 15% compared with exercise time during the placebo test. Mean time to 1 mm of ST depression at 24 hours was increased by 8% with 5 mg and by 18% with 10 mg (p less than 0.001 vs placebo; p less than 0.01 between doses). Total exercise time at 24 hours was increased with both doses (p less than 0.001), with greater efficacy with the 10-mg dose (p less than 0.05 vs 5 mg).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1991

[Heparin anticoagulant activity: new knowledge and future prospects].

The present knowledge about the heparin molecular structure has been reported by current scientific literature and especially the relationship between structure and function. From the pharmacological point of view the authors suggest future lines of research in this field. The role of endothelial and the mechanisms of heparin removal from the circulation (saturation and desaturation) are analyzed. From the anticoagulation point of view the authors after the analysis of the anti-thrombin III and anti-factor Xa activity, evaluate the heparin biological action on the platelets, complement, white blood cells. They also evaluate the questions collected to heparin use in non classical clinical situations, alternative routes of administration and new therapeutic and anticoagulant procedure; the association of prostacyclin together with heparin.

Animals↗
PubMed1991

[Risk of disseminated intravascular coagulation in patients undergoing echo-guided transperineal prostatic needle biopsy with transrectal probe].

Disseminated intravascular coagulation (DIC) is a severe life-threatening acute bleeding disorder. Traumatized tissues, tumors, necrotic tissues, or bacterial endotoxines release similar material in the blood to the tissutal factors activating the coagulation cascade. This preliminary study was aimed at verifying the risk of DIC in patients undergoing US-guided transperineal prostatic biopsy with Chiba and Tru-Cut needles. To evaluate the activation degree of coagulation factors in the circulation, the authors measured the concentrations of urinary fibrin degradation products in 10 patients undergoing US-guided transperineal prostatic biopsy, both before and after biopsy, every second hour, for 24 hours. Every tube of urine sample contained soya bean trypsin inhibitor and bovine thrombin to prevent any further fibrin degradation during incubation period for the possible presence of blood in urine samples. The results showed that 7/10 patients had marked increase in urinary fibrin degradation product levels (up to 800 micrograms%), with a 3-phase trend: early peak after 2-6 hours, middle peak after 6-14 hours, and late peak after 18-24 hours, which proved the activation of the coagulation cascade.

Aged↗
PubMed1990

Fractional shortening/end-systolic stress correlation in the evaluation of left ventricular contractility in patients treated by acetate dialysis and lactate haemofiltration.

Fractional shortening/end-systolic stress (FS/ESS) correlation by echocardiography is a reliable index of left ventricular function. Acetate infusion or preload reduction due to water compartment re-equilibrium may induce ventricular derangements during dialytic treatment. In 13 patients on lactate haemofiltration (LHF) (mean age 56.8 +/- 11.9 years on regular dialytic treatment (RDT) for 75.3 +/- 56.5 months) and in seven patients on acetate haemodialysis (AHD) (mean age 48 +/- 10.7 years; on RDT for 43.9 +/- 49.2 months) fractional shortening/end-systolic stress was evaluated before and after single dialytic session. The following biochemical parameters were also studied: haematocrit (Htc), plasmatic osmolarity, ionised Ca, Na, K, and blood gases. In both groups the mean fractional shortening/end-systolic stress correlation maintained the same correlation coefficient before and after treatment (r = -0.68, P less than 0.001). Lactate haemofiltration and acetate haemodialysis by reducing the volume expansion and preload (mean interdialytic body-weight increase 2.5 +/- 0.8 kg in our patients), may decrease left ventricular contractility (Starling's law). Furthermore, acetate was postulated as a myocardial depressant. Dialysis-induced myocardial contractility variations plotted against fractional shortening/end-systolic stress correlation allowed the division of our patients into four different groups: (1) patients with increased fractional shortening and reduced end-systolic stress; (2) patients with unchanged fractional shortening and reduced end-systolic stress; (3) patients with reduced fractional shortening and increased end-systolic stress; and (4) patients with reduced fractional shortening and unchanged or reduced end-systolic stress. These groups include patients treated with either lactate haemofiltration or acetate haemodialysis. Our data cannot confirm the postulated acetate myocardial depressant activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetates↗
PubMed1989

[Echocardiographic parameters and systolic times in arterial hypertension in the elderly].

In 40 subjects, 15 mean age 70.7 +/- 5.6 with systolic-diastolic hypertension, 15 mean age 75.5 +/- 6.8 years with systolic hypertension and 10 mean age 73.6 +/- 5.1 normotensive control group we have analyzed with M-mode 2D echocardiography and echophonocardiography the following parameters: diastolic--EDD--and systolic diameter--SD--of left ventricle, diastolic thickness of septum--SSD--and posterior wall--SPPD--of left ventricle, left ventricular ejection fraction--EF--(Theicholtr. formula), radius posterior wall thickness--R/SPPD--, left ventricular mass--LVM--(Devereux' formula), and systolic time intervals (Q-A2, LVET, PEP and PEP/LVET). The differences between groups are: systolic-diastolic hypertensive patients have increased EDD, SPPD and LVM, reduction of EF and increased PEP/LVET ratio in comparison with B and C groups; systolic hypertension doesn't increase EDD; SSD and PEP/LVET increase, while the EF remains within normal limits. In the healthy aged subjects SSD, SPPD and LVM are normal.

Aged↗
PubMed1987

Cardiovascular adjustments induced by training evaluated during semisupine isotonic exercise and recovery period: an echocardiographic study.

Two groups of subjects were examined: trained athletes (group A) and a sedentary control group (group B). The subjects performed submaximal bicycle exercise in the semisupine position to evaluate the differences between the two groups with regard to cardiovascular response during exercise and recovery and to point out all the changes due to training. During the first part of exercise, cardiac output increased contemporary with heart rate and myocardial contractility as shown by the trend of the ejection fraction, higher in group A, under the same level of total vascular peripheral resistances. Later there was an increase of cardiac output for a further increase of heart rate and cardiac inotropism due to the homeometric mechanism. During recovery the heart rate and peripheral vascular resistance reduction led to an increase of venous return which set up the Frank-Starling mechanism via an increase of left ventricular dimensions. These adjustments were more efficient in group A. During exercise and recovery the heart rate-pressure product was constantly lower in group A with a significant difference to group B. Therefore, trained athletes' myocardium is more efficient than that of the sedentary group because it performs an external work load with a lower oxygen consumption.

Adult↗
PubMed1987

Cardiac damage due to nonpenetrating trauma. Report of four cases.

Four examples of cardiac damage secondary to nonpenetrating trauma in road accidents are described. Two patients had interventricular septal defect and other two had tricuspid insufficiency. In all four cases the lesion was not recognized at the time of the accident but became clinically important later. The time interval between trauma and surgery was one month to thirteen years. After surgical treatment, all four patients have continued to be asymptomatic.

Accidents, Traffic↗
PubMed1984

[Analysis of variations in cardiac performance induced by tilt and hand-grip in athletes and in untrained subjects].

The aim of the present study is to analyze variations of external cardiac work and of indices of myocardial oxygen consumption induced by upright tilting and hand-grip in volley-ball athletes (group A) in comparison with a group of normal subjects (group N). For this purpose we have used impedance cardiography, a simple, reproducible and non invasive technique, which is very reliable in evaluating both systolic time intervals and hemodynamic parameters such as stroke volume and cardiac output. No significant differences, of external cardiac work, double and triple product were observed between group A and N upon upright tilting. Hand-grip test, on the other hand, can differentiate the myocardial behaviour of trained people from that of the control group. The double product was significantly reduced in group A in comparison with group N (P less than 0.001 and the end of the test, P less than 0.05 after 30", P less than 0.001 after 1' and 3"). The triple product was significantly reduced in group A in comparison with group N at the end of the test (P less than 0.005). External cardiac work was always higher in group A in comparison with group N (P less than 0.02, at the stop P less than 0.05 after 30", P less than 0.01 after 1', P less than 0.0001 after 3'). Therefore in volleyball athletes the myocardium exhibits better mechanical performance than in normal subjects.

Blood Pressure↗