Biomedical subjects

G Plaustro

Publications and source records attributed to G Plaustro.

6 recordsLinked to original sources

PubMed1999

Coronary Doppler intensity changes during handgrip: a new method to detect coronary vasomotor tone in coronary artery disease.

OBJECTIVES: This study evaluates whether a quantitative measurement of Doppler intensity during handgrip may disclose coronary vasomotor dysfunction in patients with coronary artery disease (CAD). BACKGROUND: Atherosclerotic coronary segments show an exaggerated constrictive response to handgrip. The intensity of the scattered Doppler signal is proportional to the number of blood cells flowing through the vessel, and should be reduced during vasoconstriction. Therefore, changes in coronary flow during handgrip may be detected by measuring Doppler intensity rather than velocities. METHODS: The distal left anterior descending coronary artery (LAD) was imaged by high-resolution transthoracic color Doppler echocardiography during handgrip in 47 patients: 15 with normal coronary arteries and 32 with significant CAD involving the LAD. The Doppler signal was acquired at 70 dB dynamic range at baseline, 30-s handgrip and 5 min recovery. Peak and mean flow velocity, pressure half-time, deceleration time (ms), deceleration rate (cm/s2) and mean gray level intensity (intensity units [IU]) of the Doppler spectrum were measured in diastole. RESULTS The velocity parameters did not change significantly during handgrip both in normal and CAD patients. The Doppler intensity significantly decreased during handgrip (from 87.0 +/- 32.8 to 57.7 +/- 35.3 IU; p < 0.001) in patients with CAD, and it increased or remained unchanged in normals (from 74.1 +/- 27.3 to 85.1 +/- 31.2 IU; p = NS). The sensitivity of Doppler intensity in detecting CAD was 84.4%, specificity 93.3%, negative predictive value 73.7% and positive predictive value 96.4%. CONCLUSIONS: Doppler intensity measured by transthoracic echocardiography during handgrip allows the detection of CAD and coronary vasomotor dysfunction.

Blood Flow Velocity↗

PubMed1998

Imaging of the distal left anterior descending coronary artery by transthoracic color-Doppler echocardiography.

Two-dimensional echocardiography evaluates the effect of myocardial ischemia on left ventricular wall motion, but a direct measure of coronary flow by this method is still lacking. The aim of the present study is to evaluate the efficacy of new, high-resolution ultrasound equipment designed to image by color Doppler transthoracic echocardiography the epicardial and intramural coronary vessels. We have studied 33 consecutive patients in apical projections, to detect by color Doppler > or = 1 segments of the middle-distal tract of the left anterior descending coronary artery. In 25 of 33 patients (76%), the middle-distal tract of the left anterior descending coronary artery was imaged by color Doppler. In 15 of 33 patients (46%), the periapical tract of the left anterior descending was imaged along with its perforating branches. In 2 of 4 patients who had coronary artery bypass grafting, the anastomosis between the left internal mammary artery and the left anterior descending coronary artery was imaged. Once the coronary artery was imaged, pulsed Doppler was used to measure coronary blood flow velocity at rest. Peak and mean flow velocity, as well as the deceleration time (msec) and deceleration rate (cm/sec2), were measured on the diastolic phase of the Doppler tracing. In all 25 patients, it was possible to measure by pulsed Doppler the coronary flow velocity pattern characterized by a typical prevalent diastolic component. Peak diastolic flow velocity was 50 +/- 17 cm/sec and mean diastolic flow velocity was 37 +/- 12 cm/sec. The deceleration time was 916.2 +/- 429.1 msec and the deceleration rate was 86.3 +/- 69.3 cm/sec2. The Doppler pattern of the grafted mammary artery was different from the native mammary flow. This new noninvasive imaging technique of the coronary arteries promises to expand the field of diagnostic and experimental echocardiography and brings new insight into the pathophysiology of ischemic heart disease.

Adult↗

PubMed1998

[Visualization of native internal mammary arteries and aorto-coronary graft by means of high resolution color Doppler ultrasonography].

The internal mammary artery is routinely used for coronary artery bypass grafting because of its optimal long-term patency profile. This vessel can be imaged by angiography, but only the proximal tract at the origin from the succlavian artery can be imaged by conventional echography. The aim of our study was to visualize the intrathoracic course of the native and grafted internal mammary arteries by a new ultrasound equipment which allows high-resolution transthoracic color Doppler imaging of the chest wall vessels and coronary arteries. We studied 35 patients, 16 non operated and 19 operated of coronary surgery with the internal mammary artery grafted to the left anterior descending coronary artery. We used a multifrequency 3.5-7 MHz transducer with a small insonating surface, placed at the second-fifth intercostal space at the left and right sternal border, to image the native mammary arteries. The grafted mammary artery was detected at the fourth-fifth left intercostal space 2-4 cm lateral to the sternal border. The native left internal mammary artery was visualized in all 16 non operated patients, and the right internal mammary artery in 14/16 (87%). The native left internal mammary artery peak flow velocity was 41-160 cm/s (mean 81 +/- 34 cm/s), and the mean flow velocity was 28-89 cm/s (mean 45 +/- 17 cm/s). The right internal mammary artery peak flow velocity was 35-153 cm/s (mean 82 +/- 36 cm/s), and mean flow velocity was 21-82 cm/s (mean 46 +/- 22 cm/s). The grafted left internal mammary artery was visualized in 16/19 patients (84%), evaluated at 6 days to 36 months after surgery. Peak diastolic flow velocity ranged from 24 to 80 cm/s (mean 48 +/- 17 cm/s), and mean diastolic flow velocity ranged from 13 to 57 cm/s (mean 33 +/- 11 cm/s). The left anterior descending peak flow velocity distal to the anastomosis was 22-62 cm/s (mean 37 +/- 15 cm/s) and mean flow velocity was 18-53 cm/s (mean 29 +/- 12 cm/s). We conclude that transthoracic color Doppler echocardiography allows to image the native and grafted mammary arteries, with potential clinical applications in the management of patients with coronary artery disease.

Adult↗

PubMed1998

[Natural harmonic echocardiography].

The acquisition of echocardiographic images in harmonic mode (a frequency double than the transmitted, or fundamental) improves imaging quality. We assessed whether harmonic imaging improves the detection of endocardial borders, evaluation of ventricular function and diagnostic confidence in the clinical arena. We have studied in fundamental and harmonic imaging 45 patients (age 20-89 years, mean 53 years) using a multifrequency transthoracic probe transmitting at 1.75 MHz and receiving at 3.5 MHz (Acuson Sequoia). In 34 low echogenic patients we assessed left ventricular function. The remaining 11 patients represented selected cases (i.e. atrial septal aneurysm, aortic dissection, endocarditis and atrial septal defect). The echocardiographic images were recorded on a magneto-optical disk and analyzed by two blinded observers. Endocardial definition has been semiquantitatively evaluated assigning a 0-4 score for each of the 16 segments of the left ventricle. A score of 0 was allotted to the non-visualizable segments and a score of 4 to the best detectable segments. Ejection fraction was calculated in each patient from the apical 4-chamber view. We compared endocardial border definition and ejection fraction at rest, in fundamental and harmonic mode, and assessed the interobserver agreement in the calculation of ejection fraction. Harmonic images always showed a better definition and lower noise compared to fundamental. Endocardial border definition was significantly improved in all segments (from 1.3 +/- 1.1 fundamental to 2.9 +/- 1.0 harmonic). Forty-two segments were non detectable in fundamental (score 0) compared to 5 in harmonic. Of these 42 segments, 37 were detectable in harmonic, with a score of 2.0 +/- 1.0. Conversely, none of the 5 segments non detectable in harmonic could be visualized in fundamental. The interobserver agreement in calculating ejection fraction was improved by harmonic imaging compared to fundamental (r = 0.91 and r = 0.67, respectively). In the selected clinical cases the diagnosis was easier and faster by harmonic imaging. The harmonic mode drastically improves echocardiographic imaging, it may be used routinely and reduce the need for more invasive techniques such as transesophageal echocardiography.

Adult↗

PubMed1997

[Study of the coronary flow with high resolution transthoracic echocardiography and nondirectional Doppler].

Two-dimensional echocardiography allows to evaluate the effect of myocardial ischemia on left ventricular wall motion, but a direct measure of coronary flow by this method is still lacking. The aim of the present study was to evaluate the efficacy of a new, high-resolution echocardiographic equipment designed to image the epicardial and intramural coronary vessels by non directional Doppler. We studied 33 consecutive patients by transthoracic echocardiography in apical projections, to detect one or more segments of the left anterior descending coronary artery by non directional Doppler. Once the coronary artery has been imaged, pulsed Doppler was used to measure coronary blood flow velocity at rest. Peak and mean flow velocities were measured on the diastolic phase of the Doppler spectrum. In 25/33 patients (75.7%) the middle-distal tract of the left anterior descending coronary artery was imaged by non directional Doppler. In 15/33 patients (45.5%) the periapical tract of the left anterior descending coronary artery was imaged along with its perforating branches. In 2 out of 4 patients operated of coronary artery bypass grafting, the anastomosis between the left internal mammary artery and the left anterior descending coronary artery was imaged. In all 25 patients it was possible to measure by pulsed Doppler the coronary velocity flow pattern, characterized by a typical prevalent diastolic component. Peak diastolic flow velocity was 49.98 +/- 17.30 cm/s and mean diastolic flow velocity was 36.52 +/- 11.91 cm/s. The Doppler pattern of the grafted mammary artery was different from the native mammary flow. This new non invasive imaging technique of the coronary arteries promises to expand the field of diagnostic and experimental echocardiography and brings new insight into the pathophysiology of ischemic heart disease.

Aged↗

PubMed1997

Cor triatriatum associated with degenerative aortic insufficiency in an adult patient.

Cor triatriatum is a rare cardiac anomaly which can be congenital or acquired in origin. Congenital cor triatriatum is due to an alteration of the common pulmonary vein resorption and therefore the left atrium is divided into two chambers, a proximal one, in communication with the pulmonary veins, and a distal one, in communication with the mitral valve orifice. The diagnosis is usually made at birth, but in rare cases, when the communication between the two chambers is wide and the patient is asymptomatic, the lesions may be diagnosed incidentally during a routine echocardiographic examination. We report a 32-year-old man, admitted to our hospital with a diagnosis of aortic insufficiency, in whom echocardiography revealed the presence of cor triatriatum. The patient underwent aortic valve replacement and resection of the atrial membrane. Histology of the aortic valve revealed myxoid degeneration of the spongiosa.

Adult↗