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P Voci

Publications and source records attributed to P Voci.

At least 37 records · Page 2Linked to original sources
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

Neuromuscular relaxants in non-cardiac surgery after cardiomyoplasty.

PURPOSE: Dynamic cardiomyoplasty is a therapeutic alternative to heart transplantation in irreversible cardiac insufficiency. Little information exists about the use of muscle relaxants in patients with cardiomyoplasty. In particular, it is not clear if the muscle flap is responsive to neuromuscular blockers. The purpose of this report is to describe the safe use of vecuronium in a patient with cardiomyoplasty. CLINICAL FEATURES: A 59-yr-old man, after cardiomyoplasty for dilated cardiomyopathy two years earlier, underwent general anaesthesia with fentanyl, propofol and vecuronium during surgery for intestinal ischaemia. Intraoperative transthoracic echocardiography showed that vecuronium did not affect muscle flap motion. Two days after surgery he died in septic shock. Post-mortem histological and immunohistochemical examination showed nervous degeneration of the flap probably as a result of the chronic low frequency pacing. There was also an increase in extrajunctional receptors and an alteration in junctional receptors, as demonstrated by the negative reaction to anti-synaptophysin antibodies, used to identify the neuromuscular plate. CONCLUSION: In patients undergoing non-cardiac surgery after previous cardiomyoplasty, muscle relaxants, such as vecuronium, may be used safely. Depolarising agents, such as succinylcholine, should probably be avoided because of the possible exaggerated actions on extrajunctional receptors.

Cardiomyoplasty↗
PubMed1998

Tissue-type plasminogen activator therapy versus primary coronary angioplasty: impact on myocardial tissue perfusion and regional function 1 month after uncomplicated myocardial infarction.

OBJECTIVES: This study sought to compare the impact of primary coronary angioplasty and thrombolytic therapy for acute myocardial infarction (AMI) on 1-month infarct size and microvascular perfusion. BACKGROUND: The effect of the reperfusion strategies of primary coronary angioplasty and thrombolytic therapy on microvascular integrity still remains to be determined. METHODS: Sixty-two consecutive patients with a first AMI, undergoing intravenous tissue-type plasminogen activator (t-PA) therapy (32 patients, Group I) or primary angioplasty (30 patients, Group II), were studied. Only patients with 1-month Thrombolysis in Myocardial Infarction (TIMI) flow grade 2 or 3 were selected for the study. Patients in whom primary angioplasty was unsuccessful or those with clinical evidence of failed reperfusion were excluded. Microvascular perfusion was assessed at 1 month by intracoronary injection of sonicated microbubbles. Contrast score index (CSI) and wall motion score index (WMSI) were derived using qualitative methods. RESULTS: At baseline there were no significant differences between groups for age, risk factors, time to hospital presentation, Killip class on admission, prevalence of multivessel disease or anterior infarct site, infarct area extension before reperfusion, peak creatine kinase levels and postinfarction treatment. Conversely, significant differences between groups were found at follow-up for percent residual infarct related-artery (IRA) stenosis (70 +/- 12 vs 36 +/- 14 [mean +/- SD], p = 0.0001), CSI (1.02 +/- 0.4 vs. 1.49 +/- 0.5, p = 0.0003) and WMSI (1.67 +/- 0.3 vs. 1.45 +/- 0.3, p = 0.015). In particular, in the subset of patients with TIMI grade 3 flow, a perfusion defect occurred in one or more segments subtended by the IRA in 72% of Group I versus 31% of Group II patients (p < 0.00001) and in 27% of Group I versus 8% of Group II segments (p < 0.00001). CONCLUSIONS: The present study shows, in a highly selected cohort with successful IRA recanalization, that primary angioplasty is more effective than thrombolysis in preserving microvascular flow and preventing extension of myocardial damage at 1-month after AMI.

Age Factors↗
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

"Patch-glue" annular reconstruction for mitral valve replacement in severely calcified mitral annulus.

Mitral valve replacement in severe annular calcification may be complicated by atrioventricular rupture, left circumflex coronary artery injury, and thromboembolic events. Mitral valve replacement was performed in 2 patients with massive annular calcification, by suturing a Tissucol fibrin glue-treated Teflon patch on the posterolateral atrial wall. After 30 and 34 months, respectively, the valve was normally functioning and the patients were asymptomatic and free from hemorrhagic and thromboembolic events.

Aged↗
PubMed1997

Collateral flow prevents unintentional myocardial ischemia during antegrade cardioplegia in patients undergoing coronary artery bypass grafting.

OBJECTIVE: We evaluated, in the prevention of perioperative unintentional myocardial ischemia, the role of coronary collateral flow in patients with left anterior descending coronary artery stenosis or occlusion who underwent elective coronary artery bypass grafting. METHODS: Coronary lesions and collaterals were assessed by coronary angiography in 21 patients. Anteroseptal myocardial viability was evaluated by dobutamine echocardiography. Antegrade perfusion of cardioplegic solution was assessed by myocardial contrast echocardiography. Time-intensity curves were generated from the anteroseptal region. Twelve parameters were measured and averaged in the following four groups of patients: those with stenosis of the left anterior descending artery and poor collaterals; those with stenosis of the left anterior descending artery and good collaterals; those with occlusion of the left anterior descending artery and good collaterals; and those with occlusion of the left anterior descending artery and poor collaterals. RESULTS: Time-intensity curves were significantly different in patients with stenosis versus occlusion of the left anterior descending artery (p < 0.005); multiple comparisons with Bonferroni's correction showed that this difference was mainly a result of the impact of collateral circulation (p < 0.01). However, the role of collaterals was nonsignificant within the groups with stenosis and occlusion of the left anterior descending artery. Patients with occlusion of the left anterior descending artery and good collaterals had perfusion parameters similar to those of patients with stenosis of the left anterior descending artery (p = not significant), except for the ascending slope and time to peak values (p < 0.05 and p < 0.01, respectively), which reflected a higher flow resistance in the collateral circulation. Regional systolic function after coronary artery bypass grafting was depressed in patients with poor collaterals and poor perfusion of cardioplegic solution, as compared with findings in other subgroups. CONCLUSIONS: Incomplete myocardial protection may impair the early recovery of function after coronary artery bypass grafting.

Cell Survival↗
PubMed1997

Combined use of dobutamine echocardiography and myocardial contrast echocardiography in predicting regional dysfunction recovery after coronary revascularization in patients with recent myocardial infarction.

BACKGROUND: Myocardial contrast echocardiography and dobutamine echocardiography have recently emerged as potentially useful clinical tools to detect reversible myocardial dysfunction. However, the relative accuracy of these two techniques in predicting regional wall motion improvement after coronary interventions is still unclear. The aim of the present study was to compare their diagnostic value in predicting functional recovery after coronary revascularization in patients with recent acute myocardial infarction. METHODS AND RESULTS: Twenty-four patients with acute myocardial infarction underwent myocardial contrast echocardiography and dobutamine echocardiography within 2 weeks of hospital admission. Infarct zone contrast score and wall motion score indexes were derived in each patient. Infarct-related artery revascularization was performed before hospital discharge in all selected patients. Resting echocardiography was repeated 3 months after revascularization, and regional function recovery was analysed. The degree of wall motion score improvement at 3-month follow-up and the percentage of positive responses to dobutamine echo were greater (P < 0.001 and P < 0.002, respectively) in patients with a higher baseline contrast score (> or = 0.50). Conversely, no significant changes were observed either during dobutamine echo or after revascularization in the group of patients without residual perfusion within the infarct area. Diagnostic agreement between both techniques in predicting reversible dysfunction was high (81% of segments). The sensitivity and negative predictive value in predicting functional outcome were 100% (95% confidence interval [CI], 87% to 100%) and 100% (95% CI, 93% to 100%) by contrast echo, and 85% (95% CI, 66% to 96%) and 93% (95% CI, 84% to 98%) by dobutamine echo. The specificity and positive predictive value were 90% (95% CI, 80% to 96%) and 81% (95% CI, 64% to 93%) by contrast echo, and 88% (95% CI, 78% to 95%) and 76% (95% CI, 58% to 90%) by dobutamine echo. The combination of myocardial contrast and dobutamine echocardiography positive responses improved specificity and positive predictive value in detecting functional recovery after revascularization to 100% (95% CI, 94% to 100%) and 100% (95% CI, 85% to 100%), respectively. However, the sensitivity and negative predictive value slightly decreased with the use of both methods (85% [95% CI, 66% to 96%)] and (93%[95% CI, 85% to 98%)], respectively. CONCLUSIONS: In patients with recent myocardial infarction, reversible dysfunction after coronary revascularization and the response to dobutamine infusion are strictly dependent on microvascular integrity. However, microvascular perfusion does not always imply functional recovery after coronary revascularization. The integration with dobutamine echo results seems particularly helpful to further improve myocardial contrast echo specificity and positive predictive values.

Adult↗
PubMed1997

Opacification of the thoracic aorta after venous injection of sonicated albumin microbubbles. Implications for aortic dissection.

This study was designed to assess the feasibility of thoracic aorta opacification after intravenous injection of sonicated albumin microbubbles in patients with and without aortic dissection. Twenty-one patients were studied by transesophageal echocardiography. In 11 patients without aortic dissection, the opacification of the left ventricular outflow tract, aortic root and descending aorta was evaluated. Ten patients with aortic dissection were studied to assess perfusion of the true and false lumen. The left ventricular outflow tract, aortic root and descending aorta were opacified in all patients, with a systolic increase in contrast at visual analysis and at videodensitometry. The differentiation between false and true lumen was improved and was crucial in 1 case of type A chronic dissection. The intimal tear was detected in 7/9 cases by color Doppler vs 9/9 cases by contrast echocardiography. The noninvasive ultrasound opacification of thoracic aorta is feasible and may improve the diagnosis of aortic dissection.

Adult↗
PubMed1997

Assessment of left ventricular systolic function in low-echogenic patients by intravenous Infoson injection during dopamine echocardiography. An open, phase III trial.

This trial evaluated whether the intravenous injection of an ultrasound contrast agent (Infoson) facilitates the assessment of systolic function in 40 low-echogenic patients undergoing low-dose (4 mcg/kg/min) dopamine echocardiography. Interobserver difference in calculated ejection fraction at entry was > 10%. Echocardiographic monitoring was performed in the apical 4-chamber view at four intervals: baseline, no contrast; first Infoson injection; dopamine infusion, no contrast; dopamine infusion+second Infoson injection. The left ventricle was divided into 5 segments and analysis was performed by two blinded observers. Wall motion abnormalities, ejection fraction and the confidence in detecting the endocardial border, were assessed. Infoson provided adequate left ventricular opacification in 90% of the injections, with a significant improvement in endocardial border detection. The interobserver variability of ejection fraction measurements was significantly reduced. The probability of attaining concordance between the investigators on wall motion assessment improved significantly. These results suggest potential applications in stress echocardiography.

Aged↗
PubMed1997

[Who are the "non-dippers": an insight from the ambulatory monitoring of arterial pressure in heart transplant patients].

This study was performed in order to define who are the "non-dippers", knowing that their present definition does not imply any explanation about the mechanisms. The investigation was performed on 34 heart transplanted patients, 28 males (mean age 52 +/- 11 years) and 6 women (mean age 35 +/- 14 years), knowing that the "non-dippers" were described as the hypertensives who are devoid of the expected nocturnal fall in blood pressure (BP). The "non-dipping" phenomenon was investigated by exploring the BP 24-h pattern via ambulatory non-invasive BP monitoring, and by applying the rhythmometric analysis for quantifying the BP circadian rhythm. The study provided evidence that the "non-dippers" can be found among the hypertensives as well as the normotensives, suggesting that high BP is not a necessary condition for the "non-dipping" phenomenon, and vice versa. Both the normotensive and hypertensive "non-dippers" were seen to show stereotypic changes in BP circadian rhythm. There are normotensive and hypertensive "non-dippers" with or without the BP circadian rhythm. The "rhythmic non-dippers" show a BP circadian rhythm which is inverted in phase or demodulated in amplitude. The "non-dippers" are, thus, a heterogeneous category.

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↗
PubMed1996

Anaesthesia for caesarean section in a Marfan patient with recurrent aortic dissection.

PURPOSE: We report the anaesthetic management of a 34-yr-old pregnant woman with recurrent aortic dissection and Marfan syndrome for Caesarean section. CLINICAL FEATURES: She presented at 28 wk gestation with recurrent aortic dissection and had undergone aortic valve replacement and coronary ostia reimplantation (Bentall procedure) in the first trimester of pregnancy. She was treated in hospital with labetalol, anticoagulants and steroids and daily echocardiographic examination until 34 wk when caesarean section was planned. After positioning radial artery and CVP catheters and a transoesophageal echocardiographic probe, general anaesthesia was induced with thiopentone and maintained with isoflurane, and endotracheal intubation was facilitated with vecuronium. The site of incision was infiltrated with lidocaine before surgery which was uneventful. The patient was discharged at 10 days. CONCLUSIONS: With appropriate preoperative care and monitoring, uneventful general anaesthesia for caesarean section was achieved in a patient with Marfan syndrome in the presence of recurrent aortic dissection.

Adult↗
PubMed1996

Transesophageal echocardiography in critically-ill patients using a miniaturized probe: feasibility, efficacy and indications.

Transesophageal echocardiography (TEE) with standard probes may be unsuccessful in emergencies, and in critically-ill or non collaborative patients. A miniaturized pediatric probe was used to overcome these limitations. Thirty-nine patients (age 18-87 years, height 155-184 cm, weight 45-102 kg) were studied with the pediatric probe, and 21 of them were studied using both the pediatric and adult probes in a random sequence. Feasibility, efficacy and patient's compliance were assessed. The use of the pediatric probe was mandatory in 18 critically-ill and/or non collaborative patients for the following reasons: contraindication to sedation in 15 patients with respiratory failure and/ or with unstable hemodynamics (12 not intubated patients) or patients undergoing electroencephalographic monitoring (3 intubated patients); inability to advance the probe into the esophagus in 1 patient with esophageal compression from intrathoracic struma and in 2 patients with stenosing esophageal cancer. Imaging projections and diagnostic accuracy in a wide range of cardiac, aortic and mediastinal diseases were similar for both the pediatric and adult probes. Patient's compliance was much improved by the pediatric probe. In conclusion, TEE by pediatric probes can be used in critically-ill adult patients when the approach with the standard probe is unfeasible or when sedation is undesirable.

Adult↗