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F Lattanzi

Publications and source records attributed to F Lattanzi.

83 records · Page 5Linked to original sources
PubMed1985

Dipyridamole-echocardiography test in effort angina pectoris.

This study assesses the clinical feasibility and usefulness of dipyridamole infusion for the detection of coronary artery disease (CAD) by using 2-dimensional echocardiography (2-D echo) and 12-lead electrocardiographic monitoring. Dipyridamole infusion (0.14 mg/kg/min for 4 minutes) was performed in 66 consecutive patients with effort chest pain and in 9 control subjects. Among the 28 patients with positive dipyridamole-echocardiography test responses, 18 had diagnostic electrocardiographic changes (ST-segment depression on anterolateral leads), but these changes were unrelated to the site of asynergy. The dipyridamole-echocardiography test had an overall sensitivity of 56% and specificity of 100% for the presence of CAD. Exercise stress testing (EST) had an overall sensitivity of 62% and a specificity of 80%. Thus, the dipyridamole-echocardiography test, which is feasible in essentially all patients with good basal echocardiograms, has a lower overall sensitivity in detecting CAD than EST but a higher specificity, detects the site of apparent ischemia as identified by regional asynergy more precisely than EST, and can unmask electrocardiographically silent effort ischemia.

Adult↗
PubMed1985

Angle dependence of ultrasonic backscatter in arterial tissues: a study in vitro.

The object of this study was to obtain quantitative data on the angle dependence of reflected ultrasound signals in freshly excised normal human arterial walls and those with different degrees of atherosclerotic involvement (fatty, fibrofatty, fibrous, or calcified). Fifteen specimens were evaluated in each pathologic subset. The backscatter coefficient (BS, expressed as cm-1 X steradians -1), measured at the single frequency of 10 MHz, was evaluated at a normal angle of incidence of the interrogating beam to the tissue sample and over an angular span of 60 degrees (+/- 30 degrees around normal incidence, 2 degree steps). BS measured at normal incidence separated normal (10(-2) X 0.155 +/- 0.018; mean +/- SE) from fibrofatty (10(-1) X 0.0103 +/- 0.008), fibrous (10(-1) X 0.182 +/- 0.016), and calcified (0.202 +/- 0.016) specimens; normal and fatty (10(-3) X 0.759 +/- 0.142) and fibrofatty and fibrous samples could not be distinguished from each other in a statistically significant way. Angular scattering measurements identified two patterns: A "directive" pattern, characterized by a strongly angle-dependent BS that falls abruptly when the beam is moved slightly away from normal incidence. This pattern was typical of calcified, fibrous, and less markedly, fibrofatty and normal samples. A "nondirective" pattern, characterized by a BS that is not significantly angle dependent and fluctuates throughout the entire angular range. This was typical of fatty samples.

Aorta↗
PubMedDate not supplied

In vivo radiofrequency ultrasound analysis of normal human heart structures.

Twenty young subjects were studied with a microprocessor system for quantitative analysis of backscattered radiofrequency (RF) signals from normal heart structures. This system allows an "on line" quantitative evaluation of the amplitude of the RF "native" signal, before the chain of processing and display, with the acquisition gate displayed on a conventional M-mode machine. Septum, posterior wall, and anterior mitral leaflet were analyzed. The gate length was kept at 3 microseconds (2.35 mm) for the ventricular walls (excluding endo- and epicardial reflections), and at 1 microsecond (0.8 mm) for the mitral valve. Integrated backscatter index (IBI) was calculated as the time integral of [u(t)[, where u(t) = i(t) X s(t); is the time sequence of backscattered echoes and s(t) is the time gate delimiting the thickness of the insonated tissue. The IBI was expressed in percent, normalized for the pericardial interface (the strongest reflection was assumed to be 100%). The percent IBI for the septum was found to be 22 +/- 4%; for the posterior wall it was 17 +/- 3%; for the anterior mitral leaflet it was 5 +/- 2%. A second reading of the same structures was performed by the previous observer and by a new one. Good intraobserver (r = 0.92) and interobserver (r = 0.88) correlations were obtained. In conclusion, a regional variation in echo amplitude from different heart structures can be observed in man. This set of values can be used as normal values for future studies in pathologic conditions.

Adult↗
PubMedDate not supplied

[The dipyridamole-echo-ECG test in hypertensives with microvascular angina].

Microvascular angina - chest pain syndrome in the presence of angiographically normal epicardial coronary arteries and reduced flow reserve - has been also described in patients with essential hypertension and it has been linked to the development of left ventricular hypertrophy. Dipyridamole-Echocardiography Test (DET: 2D-echo and 12 lead ECG monitoring with dipyridamole infusion, up to 0.84 mg/kg over 10') was performed in 28 essential hypertensives meeting the following inclusion criteria; 1) history of chest pain; 2) angiographically normal coronary arteries; 3) normal resting regional and global left ventricular function. A group of 12 (age and sex matched) normotensives with the same inclusion criteria, as well as with negative exercise stress test, was also evaluated. During DET, none, either in essential hypertensives or in control group, developed a regional dyssynergy of contraction; 15 in essential hypertensives, and 2 in control group had a diagnostic (greater than 0.1 mVolt from baseline) ST segment depression on ECG tracing (54 vs 17% p less than 0.01); 16 in essential hypertensives and 2 in control group had chest pain (57 vs 17%, p less than 0.01). None of the control group and 9 of the essential hypertensives had echocardiographically assessed left ventricular hypertrophy. In the essential hypertensives group, ventricular hypertrophy was present in 7/20 patients with and in 2/8 patients without dipyridamole induced chest pain and/or ST segment depression (35 vs 25%, p = ns). In conclusion, essential hypertensives patients with chest pain and angiographically normal coronary arteries frequently show "echocardiographically silent" angina and/or ST segment depression during DET. The presence of ventricular hypertrophy does not appear to be a prerequisite for the induction of angina in these patients.

Angina Pectoris↗
PubMedDate not supplied

[Increase in tolerance to physical effort in patients with X syndrome after acute administration of aminophylline].

Myocardial flow maldistribution and transmural steal phenomena, due to excessive arteriolar dilation elicited by elevated adenosine release during exercise, might be the mechanism of myocardial ischemia in patients with syndrome X. The effect of the adenosine receptor blocker aminophylline (AM) on effort ischemia in patients with syndrome X was tested: following double blind, randomized intravenous infusion of aminophylline (6 mg/kg over 15 minutes) or placebo, 8 patients with syndrome X underwent exercise stress test. After AM administration there was an increase in work tolerance (AM = 7.7 +/- 1.2 minutes of exercise vs placebo = 5.6 +/- 0.9, p less than 0.01) paralleled by an increase of the ischemic threshold, evaluated through the rate pressure product (mmHg x beats/min x 1/100) at 0.1 mV of ST-segment depression or at peak exercise (AM = 278 +/- 55 vs placebo = 230 +/- 24, p less than 0.05). AM prevented the occurrence of ischemic ECG signs in all 8 patients. Thus, at a dosage which effectively inhibits adenosine receptors, aminophylline infusion exerts beneficial effect on exercise induced ischemia in syndrome X, possibly through the prevention of transmural steal phenomena, elicited by inappropriate adenosine release during effort.

Adult↗