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C Palombo

Publications and source records attributed to C Palombo.

At least 19 recordsLinked to original sources
PubMed1999

Alpha-adrenergic blockade improves recovery of myocardial perfusion and function after coronary stenting in patients with acute myocardial infarction.

BACKGROUND: AMI reperfusion by thrombolysis does not improve TIMI flow and LV function. The role of infarct-related artery (IRA) stenosis and superimposed changes in coronary vasomotor tone in maintaining LV dysfunction must be elucidated. METHODS AND RESULTS: Forty patients underwent diagnostic angiography 24 hours after thrombolysis. Seventy-two hours after thrombolysis, the culprit lesion was dilated with coronary stenting. During angioplasty, LV function was monitored by transesophageal echocardiography. Percent regional systolic thickening was quantitatively assessed before PTCA, soon after stenting, 15 minutes after stenting, and after phentolamine 12 microg/kg IC (n=10), the alpha1-blocker urapidil 600 microg/kg IV (n=10), or saline (n=10). Ten patients pretreated with beta-blockers received urapidil 10 mg IC. Coronary stenting significantly improved thickening in IRA-dependent and in non-IRA-dependent myocardium (from 27+/-15% to 38+/-16% and from 40+/-15% to 45+/-15%, respectively). Simultaneously, TIMI frame count decreased from 39+/-11 and 40+/-11 in the IRA and non-IRA, respectively, to 23+/-10 and 25+/-7 (P<0.05). Fifteen minutes after stenting, thickening worsened in both IRA- and non-IRA-dependent myocardium (to 19+/-14% and 28+/-14%, P<0.05), and TIMI frame count returned, in both the IRA and non-IRA, to the values obtained before stenting. Phentolamine and urapidil increased thickening to 36+/-17% and 41+/-14% in IRA and to 48+/-11% and 49+/-17% in non-IRA myocardium respectively, and TIMI frame count decreased to 16+/-6 and to 17+/-5, respectively. Changes were attenuated with beta-blocker pretreatment. CONCLUSIONS: Our finding that alpha-adrenergic blockade attenuates vasoconstriction and postischemic LV dysfunction supports the hypothesis of an important role of neural mechanisms in this phenomenon.

Adrenergic alpha-Antagonists↗
PubMed1998

Postischemic left ventricular dysfunction is abolished by alpha-adrenergic blocking agents.

OBJECTIVES: We sought to evaluate the efficacy of alpha-adrenergic blocking agents in counteracting left ventricular (LV) dysfunction occurring after transient ischemia in humans. BACKGROUND: The mechanisms underlying postischemic LV dysfunction are largely unknown. METHODS: Percutaneous transluminal coronary angioplasty (PTCA) provides a clinical model of ischemia and reperfusion. In 50 patients undergoing coronary stenting for 77+/-5% stenosis, LV function was monitored by transesophageal echocardiography during and 30-min after PTCA. Fifteen minutes after stenting, 15 patients received 12 microg/kg body weight of the alpha-blocker phentolamine intracoronarily, 15 patients received 600 microg/kg of the alpha1-blocker urapidil intravenously, 10 patients received the combination of phentolamine and 1.2 mg of propranolol intracoronarily, and 10 patients received saline. RESULTS: Fifteen minutes after successful coronary dilation, significant contractile dysfunction occurred in previously ischemic and nonischemic myocardium. LV dysfunction was accompanied by an increase in coronary resistance and diffuse vasoconstriction. Alpha-blockers counteracted LV dysfunction and coronary resistance and the increase in vasoconstriction. Phentolamine and urapidil increased global LV shortening from 34+/-9% to 45+/-8% and to 49+/-8%, respectively (p < 0.05). After the administration of propranolol combined with phentolamine, LV dysfunction remained unchanged (34+/-6%), as in control subjects. CONCLUSIONS: LV dysfunction occurs after PTCA, as described in animal models after ischemia. Alpha-blockers abolished LV, macrocirculatory and microcirculatory dysfunction, whereas the alpha-blocker effect was prevented by combining alpha- and beta-blockers. The evidence of diffuse rather than regional dysfunction, together with the opposite effects of alpha- and beta-blockade, supports the hypothesis of neural mechanisms eliciting postischemic LV dysfunction.

Adrenergic alpha-Antagonists↗
PubMed1998

Ultrafast three-dimensional ultrasound: application to carotid artery imaging.

BACKGROUND AND PURPOSE: Three-dimensional (3-D) vascular ultrasound can be expected to improve qualitative evaluation of vessel pathology and to provide quantitative data on vascular morphology and function. The objective of this study was to develop an ultrafast 3-D vascular system and to validate its performance for quantitation of atherosclerosis and assessment of regional arterial distensibility. METHODS: The quantitative analysis of focal atherosclerotic lesions was validated in vitro on 27 phantoms of fibroadipous plaques of known volume (range, 100 to 600 mm3). In vivo reproducibility of plaque volume measurement was tested in 33 patients who had a total of 47 predominantly fibroadipous carotid plaques. Distensibility assessment was validated indirectly through the evaluation of age-related changes in distensibility of common carotid artery in healthy and hypertensive subjects (25 men in each group). RESULTS: The volume of plaque phantoms measured from the 3-D data set showed a very close correlation with the true volume (r=0.99; y=0.96x+12.38; P<0.01), with the mean difference between the 2 measurements being -3.12+/-15.1 mm3. High reproducibility was found for measurement of carotid plaque volume in vivo: the mean difference between measurements from 2 observers for the same data set was 0.60+/-11.2 mm3. Indexes of arterial distensibility decreased with age in healthy population, whereas this relationship was lost in hypertensive subjects. CONCLUSIONS: Ultrafast 3-D ultrasound imaging of carotid artery demonstrates good accuracy and reproducibility for atherosclerotic plaque volume measurements. The system also allows the study of age-related degenerative vascular changes.

Aged↗
PubMed1997

Comparative effects of enalapril and verapamil on myocardial blood flow in systemic hypertension.

BACKGROUND: The comparative effects of calcium channel blockers and ACE inhibitors on myocardial blood flow (MBF) in hypertensive patients after long-term treatment are still unknown. METHODS AND RESULTS: Twenty hypertensive subjects with normal coronary arteries were randomly assigned to verapamil 240 to 480 mg/d or enalapril 10 to 40 mg/d. MBF was quantified at rest, during pacing tachycardia, and after dipyridamole by positron emission tomography and 13N-ammonia before and 6 months after treatment after 1 week of pharmacological washout. In both groups, blood pressure and heart rate during flow measurements were not different before and after therapy. Before treatment, mean MBF at rest, during pacing tachycardia, and after dipyridamole infusion was similar in the two groups; however, pacing and dipyridamole flows were significantly lower than those obtained in a control group of normotensive subjects. After treatment, in the enalapril-treated patients, MBF did not change in the three study conditions. In the verapamil-treated patients, MBF did not change at rest and significantly increased during pacing and after dipyridamole. The inhomogeneity of regional MBF distribution, evaluated from the coefficient of variation, decreased at rest after both treatments and, in the enalapril group, also during pacing. No relation was found between changes in MBF and changes in left ventricular mass. CONCLUSIONS: In arterial hypertension, MBF during pacing tachycardia and after dipyridamole is impaired. Successful therapy with verapamil increases MBF response to these stimuli, independent of changes in perfusion pressure and left ventricular mass. These results suggest that verapamil directly improves coronary microcirculatory function in hypertension. Enalapril does not significantly change MBF but reduces the inhomogeneity of regional flow distribution.

Antihypertensive Agents↗
PubMed1997

Assessment of coronary reserve by transoesophageal Doppler echocardiography. Direct comparison between different modalities of dipyridamole and adenosine administration.

BACKGROUND: This study was undertaken to compare the coronary vasodilator response to different application modalities of intravenous vasodilators, in order to identify the optimal pharmacological protocol for the evaluation of coronary reserve by means of transoesophageal Doppler echocardiography. METHODS: Blood flow velocity in the left anterior descending artery, coronary vascular resistance and left main coronary artery cross-sectional area were assessed by transoesophageal echo-Doppler during an i.v. adenosine bolus (5 mg), a 5-min adenosine infusion (infusion rate 140 micrograms. kg-1 min-1), and low (0.56 mg.kg-1. 4 min-1), and high-dose (0.84 mg.kg-1.9 min-1) dipyridamole infusions in 10 healthy normals (Group 1) and in 20 patients (Group 2) with either coronary microvascular disease (11 patients) or coronary artery disease (nine patients). RESULTS: In both groups, the highest flow velocity and the lowest coronary vascular resistance were observed during the adenosine infusion. Flow velocity values and indices of coronary vasodilator capacity observed after the adenosine bolus and the high-dose dipyridamole infusion were very close to those obtained during the adenosine infusion, especially in Group 1. Coronary flow velocity was lower and coronary vascular resistance higher after low-dose dipyridamole, significantly in Group 2. The maximal flow response to the adenosine bolus was observed within a few seconds after the injection, and was very short. The peak response to the adenosine infusion was observed 57 +/- 27 s after its start. The coronary flow velocity response to dipyridamole was dose dependent and differed between Groups 1 and 2. CONCLUSION: In combination with transoesophageal Doppler echocardiography, a short-lasting adenosine infusion at a rate of 140 micrograms.kg-1.min-1 seems to be preferable to an adenosine bolus and dipyridamole infusion. The effect of the bolus is too short for an accurate measurement of coronary flow velocity, while the dipyridamole infusion, especially at a low dose, induces a submaximal vasodilator response.

Adenosine↗
PubMed1997

Mechanisms of coronary flow reserve impairment in human hypertension. An integrated approach by transthoracic and transesophageal echocardiography.

The purpose of this study was to investigate the different mechanisms responsible for an impairment of coronary vasodilator capacity in hypertensive subjects by an integrated echocardiographic approach, including transesophageal Doppler echocardiography, which allows noninvasive monitoring of coronary flow velocity in the left anterior descending artery during pharmacological vasodilation. The study population consisted of 17 healthy control subjects and 33 hypertensive subjects: 10 without hypertrophy, 16 with mild to moderate hypertrophy, and 7 with severe left ventricular hypertrophy. Mean systolic and diastolic flow velocities were monitored basally (together with indexes of myocardial oxygen demand, such as heart rate, myocardial inotropism, and left ventricular wall stress) and during infusion of low-dose (0.56 mg/kg per 4 minutes) and high-dose (0.84 mg/kg per 9 minutes) dipyridamole. Coronary reserve was assessed as the ratio of mean diastolic velocity after high-dose dipyridamole and basal diastolic velocity, and minimum coronary resistance as the ratio of diastolic blood pressure and diastolic velocity after high-dose dipyridamole. Compared with the control group, in all hypertensive groups, coronary reserve was similarly decreased (3.54 +/- 0.84 versus 2.59 +/- 0.42, 2.29 +/- 0.46, and 2.43 +/- 0.71; P < .01) and minimum resistance increased (0.56 +/- 0.15 versus 0.75 +/- 0.31, 0.75 +/- 0.19, and 0.78 +/- 0.21 mm Hg.s-1.cm-1; P = NS). These results confirm that coronary reserve in hypertensive individuals is reduced even before the occurrence of left ventricular hypertrophy. The reduction in coronary reserve depends on both an increase in resting coronary flow and an impairment in maximal vasodilator capacity. An increase in resting flow is dependent on higher heart rate and wall stress in hypertensive subjects without ventricular hypertrophy and on increased myocardial mass in hypertensive subjects with hypertrophy. Hypertensive subjects with ventricular hypertrophy also demonstrated a significantly blunted response to low-dose dipyridamole.

Adult↗
PubMed1997

[Evaluation of cerebral perfusion during aortic clamping and cross-clamping in patients undergoing resection for abdominal aortic aneurysm. A study with transcranial doppler].

OBJECTIVE: To evaluate the cerebral blood flow parameters assessed by transcranial Doppler during aortic cross-clamping and unclamping in patients undergoing abdominal aortic aneurysmectomy. METHODS: Invasive intraoperative monitoring of mean arterial pressure (MAP) and PaCO2, and right middle cerebral artery (RMCA) monitoring of blood flow parameters (mean velocity "Vm" and pulsatility index "PI") by transcranial Doppler were performed as well as evaluation of the four parameters during these subsequent periods: pre-cross-clamping, pre-unclamping, unclamping and 1-5-10-20 minutes after abdominal aortic unclamping. RESULTS: No significative changes of MAP, PaCO2, Vm and PI were noticed during the aortic cross-clamping period (77.5 +/- 18.5 SD minutes). During aortic unclamping Vm and MAP decreased (64 +/- 20 vs 52 +/- 20 cm/sec, p < 0.05, and 101 +/- 8 vs 80 +/- 15 mmHg, p < 0.01, respectively). At the 1th post-unclamping minute there was an increase from pre-unclamping values of Vm (75 +/- 20 cm/sec, p < 0.05) and PaCO2 (42 +/- 1.5 vs 36 +/- 2 mmHg, p < 0.05), with persistent reduction of MAP (92 +/- mmHg, p < 0.05), even more evident at the 5th post-unclamping minute (Vm = 93 +/- 25 cm/sec; PaCO2 = 46 +/- 1.2 mmHg, p < 0.001, and MAP returned to pre-unclamping value), in which there was also a decrease of PI (0.65 +/- 0.16 vs 0.78 +/- 0.2, p < 0.05). At the 10th minute Vm (83 +/- 24 cm/sec, p < 0.02) and PaCO2 (41 +/- 1.5 mmHg, p < 0.05) increments were present together with persistent reduction of PI (0.69 +/- 0.17, p < 0.05), while at the 20th post-unclamping minute also Vm, PaCO2 and PI returned to their pre-unclamping values. CONCLUSIONS: The Vm decrease at aortic unclamping might correlate with the acute changes in MAP (blood steal hypovolemia) and is likely due to an inadequate cerebral autoregulatory response to abrupt MAP changes. The arterial CO2 increase after aortic unclamping could lead to a dilation of cerebral arterioles and a rise of CBF (increase of Vm and decrease of PI). Transcranial Doppler is a simple and reliable technique for the monitoring of cerebral blood flow parameters and seems to be quite suitable for the recognition and the quantification of changes in these parameters induced by surgical manoeuvres able to produce hemodynamic instability.

Aged↗
PubMed1995

Transcranial Doppler ultrasound in migraine and tension-type headache after apomorphine administration: double-blind crossover versus placebo study.

The effect of the dopaminergic agonist apomorphine on blood velocity in the middle cerebral artery has been studied in patients with migraine, tension-type headaches, and healthy subjects by means of transcranial Doppler monitoring. Following the administration of apomorphine, systolic velocity and mean velocity significantly increased and pulsatility index significantly decreased in migraineurs compared to placebo and to the other groups of subjects. These changes were dose-dependent and showed a time-curved compatible with the pharmacokinetic profile of the drug. The different effect of apomorphine in migraineurs compared with controls and tension-type headache patients implies that migraineurs have increased sensitivity to dopaminergic stimuli and suggests that transcranial Doppler monitoring after apomorphine administration could be a useful tool in the evaluation of migraineurs.

Adult↗
PubMed1995

Transesophageal echocardiography in myocardial ischemia: a review.

This article reviews established as well as emerging fields in the application of transesophageal echocardiography (TEE) in the investigation of myocardial ischemia. TEE already has a well defined and established role in stress echocardiography in patients with poor transthoracic acoustic window, and in the detection of intraoperative myocardial ischemia in cardiac and noncardiac surgery. The evaluation of right ventricular ischemia and infarction and the assessment of coronary flow reserve (CFR) are relatively new fields in the application of TEE and the potential of this technique has not yet been fully evaluated. The evidence collected and reviewed in this article is still preliminary but it presupposes a significant role of TEE in the diagnosis and pathophysiological assessment of myocardial ischemia.

Echocardiography, Transesophageal↗
PubMed1994

Diastolic function in the different patterns of left ventricular adaptation to essential hypertension.

Recent reports have shown that four distinct left ventricular anatomical patterns, with different hypertension severity and hemodynamic features, are associated with sustained arterial hypertension (normal anatomy, concentric remodeling, concentric hypertrophy and eccentric hypertrophy). The aim of this study was to evaluate left ventricular diastolic function in these different left ventricular anatomic patterns. To achieve this aim, 94 borderline-to-severe essential hypertensive patients (60 never treated before, 34 off treatment for at least 3 weeks before the study) underwent an echo-Doppler study; left ventricular thickness, dimension and mass index were obtained. Early (E) and late (A) transmitral flow velocity, their ratio (A/E) and the early filling fraction (EFF) were obtained by pulsed-wave Doppler and used as left ventricular diastolic function indexes. Differences between groups were evaluated by one-way ANOVA followed by Scheffe F-test. A normal left ventricular anatomy was found in 41 (44%), concentric remodeling in 17 (18%), concentric hypertrophy in 21 (22%) and eccentric hypertrophy in 15 (16%) patients. Early filling fraction and A/E ratio which resulted were significantly different for the groups (P < 0.001 and P < 0.002, respectively). As compared with the group with normal left ventricle, patients with concentric hypertrophy had significantly EFF and those with eccentric hypertrophy had significantly lower EFF and higher A/E ratio. Our results thus confirm the presence of distinct anatomical left ventricular adaptation patterns in arterial hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Physiological↗
PubMed1994

Echo Doppler diastolic function and exercise tolerance.

OBJECTIVE: To investigate the possible association between Doppler left ventricular filling pattern and exercise capacity in a group of normotensives to severe hypertensive patients. BACKGROUND: Invasive left ventricular filling indexes evaluated at rest are reported to be related to exercise capacity in heart failure. Whether exercise capacity is limited by abnormalities of left ventricular filling also in other less severe conditions is however unclear. METHODS: Fifty-one subjects with normal to severely elevated blood pressure underwent a standard exercise test on cycle ergometer, negative for myocardial ischemia, and a complete echo Doppler evaluation showing a basal systolic function within normal limits. RESULTS: Basal systolic function indexes were not significantly related to exercise duration. On the contrary, exercise duration was highly significantly correlated to the relative atrial contribution to left ventricular filling (0.001 < P < 0.05), in both the overall group and the two subgroups in whom exercise was interrupted because of fatigue (n = 30) or because of attaining target heart rate (n = 21). Significant correlations were also observed between exercise time and resting blood pressure, whereas no association with resting heart rate, age and body surface area was found. Exercise time also correlated to left ventricular mass and mass index but not to left ventricular volume. Multiple regression analysis showed that exercise tolerance was significantly related to diastolic blood pressure and left ventricular filling. Echo Doppler indexes of left ventricular filling are associated with exercise duration; left ventricular diastole could thus influence effort tolerance, not only in patients with cardiac insufficiency, but also in subjects with normal to elevated blood pressure levels and normal systolic function at rest.

Blood Pressure↗
PubMed1994

Twenty-four-hour ambulatory blood pressure monitoring and antihypertensive treatment: focus on ACE inhibitors.

The use of ambulatory blood pressure monitoring in clinical studies offers some advantages in comparison to the clinic blood pressure measurement. In fact, this approach does not induce any alerting reaction and provides 24-h blood pressure values that are more reproducible and not affected by the placebo effect. This allows a better evaluation of blood pressure under antihypertensive treatment and an optimization of the number of patients to be studied in pharmacologic trials. In a recent double-blind, parallel-group study, ambulatory blood pressure monitoring was used to investigate the antihypertensive efficacy of a new angiotensin-converting enzyme inhibitor, trandolapril, in 62 mild and moderate hypertensive patients. After a washout period, patients received trandolapril, 2 mg o.d., or placebo for 6 weeks, followed by a second washout period. Clinic and 24-h blood pressures were assessed at the end of each period. In comparing the pre- and post-treatment period, trandolapril significantly reduced clinic and 24-h systolic and diastolic blood pressures. The fall was evident throughout the 24 h and was statistically significant also in the last 4 h of blood pressure monitoring. The placebo group did not show any significant blood pressure change. Thus, trandolapril, 2 mg once daily, is effective in reducing blood pressure. Its efficacy over 24 h is better documented by 24-h blood pressure monitoring than by isolated clinic blood pressure measurement.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1994

Analysis of right ventricular kinesis by means of transesophageal echocardiography: present problems and perspectives.

The evaluation of right ventricular (RV) kinesis by two-dimensional echocardiography represents a difficult task. Transthoracic echocardiography can visualize the RV in several projections, but the image quality and the variability of imaging views usually do not allow quantitative analysis. We investigated the potential of transesophageal echocardiography (TEE) for evaluating RV global function and regional kinesis, in 32 controls and in 16 patients with inferior myocardial infarction (MI) and asynergy involving the inferior wall of both ventricles. Good-quality images of at least one horizontal section of the RV were obtained in 73% of subjects by conventional, 90 degrees sector and in 100% of subjects by wide-angle, "panoramic" sector. Images of the RV in short-axis view at medium level were acquired and evaluated in 93% of cases, but at basal and apical levels only in 67% and 39%, respectively. The low percentage of successful detection and evaluation of the RV at apical level can be explained by prominent motion and trabeculation of the apex. Global systolic area changes (SAC) in controls attained similar values at apical and medium levels (60% and 59%, respectively), but were significantly lower (48%, P less than 0.05) at basal level. In patients with previous inferior MI and inferoposterior asynergy, global SAC were significantly (P less than 0.01) lower at medium and basal levels (32% and 27%, respectively) compared with controls. Regional kinesis of RV was assessed as segmental SAC in 12 different segments, by fixed and float system of center of cavity.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Insulin resistance and vasodilation in essential hypertension. Studies with adenosine.

Insulin-mediated vasodilation has been proposed as a determinant of in vivo insulin sensitivity. We tested whether sustained vasodilation with adenosine could overcome the muscle insulin resistance present in mildly overweight patients with essential hypertension. Using the forearm technique, we measured the response to a 40-min local intraarterial infusion of adenosine given under fasting conditions (n = 6) or superimposed on a euglycemic insulin clamp (n = 8). In the fasting state, adenosine-induced vasodilation (forearm blood flow from 2.6 +/- 0.6 to 6.0 +/- 1.2 ml min-1dl-1, P < 0.001) was associated with a 45% rise in muscle oxygen consumption (5.9 +/- 1.0 vs 8.6 +/- 1.7 mumol min-1dl-1, P < 0.05), and a doubling of forearm glucose uptake (0.47 +/- 0.15 to 1.01 +/- 0.28 mumol min-1dl-1, P < 0.05). The latter effect remained significant also when expressed as a ratio to concomitant oxygen balance (0.08 +/- 0.03 vs 0.13 +/- 0.04 mumol mumol-1, P < 0.05), whereas for all other metabolites (lactate, pyruvate, FFA, glycerol, citrate, and beta-hydroxybutyrate) this ratio remained unchanged. During euglycemic hyperinsulinemia, whole-body glucose disposal was stimulated (to 19 +/- 3 mumol min-1kg-1), but forearm blood flow did not increase significantly above baseline (2.9 +/- 0.2 vs 3.1 +/- 0.2 ml min-1dl-1, P = NS). Forearm oxygen balance increased (by 30%, P < 0.05) and forearm glucose uptake rose fourfold (from 0.5 to 2.3 mumol min-1dl-1, P < 0.05). Superimposing an adenosine infusion into one forearm resulted in a 100% increase in blood flow (from 2.9 +/- 0.2 to 6.1 +/- 0.9 ml min-1dl-1, P < 0.001); there was, however, no further stimulation of oxygen or glucose uptake compared with the control forearm. During the clamp, the ratio of glucose to oxygen uptake was similar in the control and in the infused forearms (0.27 +/- 0.11 and 0.23 +/- 0.09, respectively), and was not altered by adenosine (0.31 +/- 0.9 and 0.29 +/- 0.10). We conclude that in insulin-re15-76sistant patients with hypertension, adenosine-induced vasodilation recruits oxidative muscle tissues and exerts a modest, direct metabolic effect to promote muscle glucose uptake in the fasting state. Despite these effects, however, adenosine does not overcome muscle insulin resistance.

Adenosine↗
PubMed1993

Intra-operative assessment of myocardial ischaemia during general surgery by transoesophageal echocardiography: present state and future perspectives.

This paper reviews the present state and future perspectives of the peri-operative application of Transoesophageal Echocardiography (TEE) for early detection of myocardial ischaemia during general surgery. The increasing clinical relevance of this problem parallels the progressively higher frequency of surgery performed in patients at relatively high cardiovascular risk, due to a longer life-span and improved anaesthetic techniques. TEE potentially provides a powerful method for detailed cardiac monitoring in patients undergoing general surgery. The detection of a new regional asynergy during echocardiographic monitoring represents an early and reliable marker of myocardial ischaemia. The sensitivity, specificity and feasibility of TEE monitoring of intraoperative myocardial function and ischaemia will be outlined and compared with those of ECG and invasive monitoring. Problems related to the interpretation of intra-operative findings, with special reference to possible non-ischaemic mechanisms responsible for intra-operative regional asynergies--which can decrease the specificity of this method--are considered. Though still under investigation, the potential contribution of ultrasonic tissue characterisation of the asynergic ventricular wall as an additional, or even alternative, marker of myocardial ischaemia, is discussed. Finally, educational problems related to the new tasks facing the anaesthesiologist involved in intra-operative echo-Doppler evaluation of cardiac function are also foreseen.

Echocardiography, Transesophageal↗
PubMed1993

[Arterial hypertension and arteries of large caliber].

In the last few years increasing attention has been given to investigate the role of large arteries in the pathophysiology of arterial hypertension and cardiovascular diseases. Thanks to their elastic properties, these vessels convert pulsatile flow in continuous flow at capillary level, thus significantly affecting the tissue perfusion. Various factors can modify the elastic properties of large arteries (arterial-wall structure alteration, vasoactive substances, elevated transmural pressure) and thus have positive or negative effect on cardiac function, vascular damage and systemic circulation. New ultrasonic techniques allow one to evaluate these vascular properties and to detect early changes in vessel structure and function. These techniques appear to be a promising tool to provide early markers of hypertensive vascular disease and of vascular risk in general, as well as to follow the vascular effects of treatment.

Arteries↗