PubMed Health⌕ Search

Biomedical subjects

G P Trevi

Publications and source records attributed to G P Trevi.

At least 19 recordsLinked to original sources
PubMed2002

GH-independent cardiotropic activities of hexarelin in patients with severe left ventricular dysfunction due to dilated and ischemic cardiomyopathy.

AIM: To investigate acute cardiotropic activities of hexarelin in patients with severe left ventricular dysfunction due to ischemic (iCMP) and dilated cardiomyopathy (dCMP). METHODS AND RESULTS: We studied the effect of intravenous hexarelin administration on growth hormone (GH) levels and left ventricular ejection fraction (LVEF) evaluated by radionuclide angiography in eight patients with dCMP (age 53.0+/-2.8, LVEF 16.7+/-2.1%) and five patients with iCMP (age 52.0+/-2.8 years, LVEF 22.6+/-2.1). Results were compared with a group of seven normal subjects (age 37.4+/-3.4 years, LVEF 64.0+/-1.5%) and seven patients with severe growth-hormone deficiency (GHD; age 42.0+/-4.4 years, LVEF 50.0+/-1.9%) previously studied with the same methodology. In dCMP and iCMP patients hexarelin induced a similar significant (P<0.05) increase in GH levels. In iCMP patients hexarelin induced a LVEF increase (peak LVEF 26.2+/-2.5%, P<0.05) as observed in normals and GHD, while in dCMP LVEF was unchanged (peak LVEF 17.7+/-1.7, P=NS). In all groups other hemodynamic parameters were unchanged. CONCLUSIONS: Acute hexarelin administration increases LVEF in iCMP patients (as in normals and GHD) but not in dCMP patients in spite of a similar GH releasing effect and basal LVEF. A possible explanation of the positive inotropic effect of hexarelin in iCMP could be a direct stimulation on viable myocardium or myocardial contractile reserve.

Adult↗
PubMed2002

[A case of pulmonary thromboembolism after interruption of treatment with unfractionated heparin].

Pulmonary embolism is a quite frequent event (incidence 1/10000/year), and blood stasis, endothelial lesions and coagulation disorders are predisposable factors. Elective treatment is heparin, but the use of this medication is associated with a possible ipercoagulative rebound effect. The case presented is a patient with unstable angina treated with heparin infusion, who developed pulmonary embolism after discontinuation of heparin treatment; the patient didn't present a genetic coagulopathy. Others risk factors have been analyzed and it was observed that discontinuation of heparin infusion could have a predominant role in the development of thrombosis. A MedLine research on the rebound effect of heparin and how to reduce it has been carried out.

Aged↗
PubMed2002

Drug-eluting stent: the emerging technique for the prevention of restenosis.

Percutaneous coronary interventions (PCI) have surpassed coronary artery bypass grafting as the most common means for treating coronary artery disease, because of materials improvement, the use of stent and pharmacotherapy. However, despite the variety of mechanical techniques such as dilatation, debulking or conventional stent implantation, the incidence of restenosis on short and mid-term follow-up is still representing an important limitation to PCI. Restenosis is mainly due to elastic recoil, negative vessel remodelling and neointimal proliferation, as a response to vessel injury induced by angioplasty devices. The use of conventional stents has provided an efficient method to avoid elastic recoil and negative vessel remodelling, thus partially reducing restenosis as compared to conventional balloon dilatation. However, neointimal proliferation (biological vessel response to injury caused by stent implantation) is not affected by stenting technique. Thus, the extensive use of coronary stent, even in complex lesions, have produced again a "new" disease: the in-stent restenosis especially in some patients' subset (diabetics) or in some lesion subset (bifurcations, long lesions, small vessels, total occlusions, diffuse disease). Therefore, the main target of today's interventional cardiologists is to resolve this problem. The combination between mechanical control of elastic recoil and negative remodelling (stent) and the control of neointimal proliferation - biological response to vessel injury - (antiproliferative drugs) is the emerging approach against restenosis. This emerging approach consists in using the stent as drug carrier to the target site. Local delivery of antiproliferative or immunosuppressive agents using a drug-coated stent is supposed to inhibit in stent restenosis. The first antiproliferative agents being used successfully in clinical trials are sirolimus and paclitaxel and, so far, the data available of these trials demonstrated a marked reduction of restenosis using sirolimus- and paclitaxel-coated stents as compared to conventional stents. However, many questions are still to be answered and several other clinical trials with drug-eluting stents are ongoing, evaluating safety and efficacy of sirolimus and paclitaxel in a larger number of patients and in different subset of coronary lesions type and morphology. Based on the very impressive results available at the present time, we can expect, in the very near future, remarkable changes in our clinical practice and the beginning of a new "era" of interventional cardiology.

Angiogenesis Inhibitors↗
PubMed2002

One year temporal pattern of neurohumoral factors and natriuretic peptides compared with clinical variables in patients with dilated cardiomyopathy.

BACKGROUND: Elevated levels of neuroendocrine peptides and hormones are some of the compensatory mechanisms activated in patients with congestive heart failure. The aim of this study was to describe their time related variability in clinically stable patients and to compare hormones and peptides levels to clinical variables. METHODS: Nineteen patients with history of congestive heart failure due to dilated cardiomyopathy and in sinus rhythm were recruited. At baseline, after 3 months, and at 1 year they underwent 6-min walk test, Minnesota Living with Heart Failure Questionnaire, and blood measurements of ANP, BNP, plasma renin activity, aldosterone, norepinephrine and epinephrine. RESULTS: After 1 year, 17 patients remained clinically stable, and did not change their therapy and functional class. Also echocardiographic data and neurohormonal parameters did not change significantly except for epinephrine that decreased significantly after 3 months and returned to a value similar to the basal one at 1 year. Two outliner values were observed for norepinephrine belonging to the only 2 patients that spontaneously withdrew the ace-inhibitor therapy during the follow-up. CONCLUSIONS: This study indicates that plasma concentration of neurohormones and peptides were fairly stable over 1 year interval in stable patients with mild-moderate heart failure due to dilated cardiomyopathy and that norepinephrine could be considered as the most sensible parameters to monitor therapy compliance.

Aged↗
PubMed2001

Different patterns of atrial activation in idiopathic atrial fibrillation: simultaneous multisite atrial mapping in patients with paroxysmal and chronic atrial fibrillation.

OBJECTIVES: We aimed to evaluate: 1) the behavior of electrical activity simultaneously in different atrial regions during atrial fibrillation (AF); 2) the difference of atrial activation between paroxysmal and chronic AF; 3) the atrial refractoriness dispersion; and 4) the correlation between the effective refractory periods (ERPs) and the FF intervals. BACKGROUND: Little data exist on the electrophysiologic characteristics of the different atrial regions in patients with AF. A more detailed knowledge of the electrical activity during AF may provide further insights to improve treatment of AF. METHODS: Right and left atria were extensively mapped in 30 patients with idiopathic AF (18 paroxysmal and 12 chronic). In different atrial locations, we analyzed 1) the FF interval duration; and 2) the grade of organization and, in case of organized electrical activity, the direction of atrial activation. Furthermore, in patients with paroxysmal AF, we determined the atrial ERP, evaluated the ERP dispersion and assessed the presence of a correlation between the ERPs and the FF intervals. RESULTS: In patients with chronic AF, we observed a shortening of the FF intervals and a greater prevalence of disorganized activity in all the atrial sites examined. In patients with paroxysmal AF, a significant dispersion of refractoriness was observed. The right lateral wall showed longer FF intervals and more organized atrial activity and, unexpectedly, the shortest mean ERPs. In contrast, the septal area showed shorter FF intervals, greater disorganization and the longest mean ERPs. CONCLUSIONS: Electrical activity during AF showed a significant spatial inhomogeneity, which was more evident in patients with paroxysmal AF. The mean FF intervals did not correlate with the mean ERPs.

Adult↗
PubMed2001

Influence of treatment delay on long-term left ventricular function in patients with acute myocardial infarction successfully treated with primary angioplasty.

BACKGROUND: Myocardial salvage has been shown to be dependent on the time elapsed from the onset of acute myocardial infarction (AMI) to reperfusion. The aim of this study was to evaluate the importance of time to reperfusion for left ventricular function recovery after primary angioplasty (percutaneous transluminal coronary angioplasty [PTCA]) for AMI. METHODS: Ninety-five patients undergoing long-term successful PTCA for AMI were studied. Echocardiography was performed before and 3, 7, 30, 90, and 180 days after PTCA. End-diastolic volume index (EDVI) and end-systolic volume index (ESVI), ejection fraction, and left ventricular wall motion score index (WMSI) were evaluated. RESULTS: Patients were divided into group A, 23 patients reperfused within 2 hours; group B, 32 patients reperfused between 2 and 4 hours; group C, 22 patients reperfused between 4 and 6 hours; and group D, 18 patients reperfused between 6 and 12 hours. Both EDVI and ESVI were reduced in groups A and B at 90 days. Groups C and D did not show any changes of EDVI and ESVI at any stage throughout the study. Ejection fraction improved only in groups A and B at 30, 90, and 180 days. At study entry, WMSI was similar in all groups. After 7 days, in group A and in group B, WMSI was improved, no changes were observed in group C, and a mild deterioration was observed in group D at 3 and 7 days. Subsequent evaluations showed progressive improvement of WMSI in all groups. CONCLUSIONS: Myocardial salvage is achieved only in patients revascularized within 4 hours from AMI onset. However, revascularization after 6 hours may be worthwhile by preventing ventricular remodeling.

Adult↗
PubMed2001

[Functional assessment of mitral stenosis].

The following parameters must be taken into account when assessing the severity of mitral stenosis: symptoms, objective examination, electrocardiogram, chest X-ray, a simple exercise test with or without cardiopulmonary test, echocardiography and lastly a hemodynamic test. Differences are often observed between the clinical and instrumental findings. In these cases a major contribution is made by the use of physical effort in response to both ECG and heart catheterization in order to quantify the patient's functional deficiency and valve response. The latter aspect must be validated using a simultaneous comparison between echocardiography and the hemodynamic test and longitudinal clinical studies.

Exercise Test↗
PubMed2001

Comparison of defibrillation thresholds using monodirectional electrical vector versus bidirectional electrical vector.

BACKGROUND: Currently, two main lead configurations are used for implantable cardioverter-defibrillators (ICD). One generates a monodirectional electrical vector by using the can surface as an active part (hot can) together with a right ventricular defibrillation coil. The other one (TRIAD) produces a bidirectional electrical vector by adding a proximal defibrillation electrode on the same lead. The purpose of this prospective study was to determine whether there is a difference between these configurations in terms of the acute defibrillation threshold (DFT). The secondary objective was to evaluate the possible sequential effect of successive arrhythmia induction and defibrillation shocks on the final DFT value. METHODS: In 44 patients (37 males, 7 females, mean age 59.18 +/- 12.05 years; mean ejection fraction 35.21 +/- 11.69%), a Hot Can Ventak family ICD (Guidant, St. Paul, MN, USA) was implanted in a left pectoral pocket. During the implant procedure, step-down to failure DFT testing was performed twice in each patient using the two different above-mentioned configurations: the bidirectional and the monodirectional. The first configuration to be tested was determined by a 1:1 randomization by center. RESULTS: The step-down DFT protocol was followed in 35 patients. The average DFT was 8.6 +/- 4.0 J for TRIAD and 10.4 +/- 4.3 J for the monodirectional (p = 0.009) lead configuration; this represents a 16.3% decrease in the DFT using a bidirectional configuration. Furthermore, no relationship between the final DFT and the number of ventricular fibrillation inductions and shocks received was observed, confirming the secondary objective. CONCLUSIONS: Compared to the monodirectional electrical vector, the bidirectional electrical vector is clearly more beneficial for the patient.

Adult↗
PubMed2001

Atrial mapping by basket catheter in patients with atrial fibrillation submitted to linear ablation.

Recently non-pharmacological therapies for atrial fibrillation (AF) have been developed. The electrophysiological mechanisms of AF is thought to be the development of multiple reentrant wavelets circulating around anatomic barriers and variable regions of functional conduction block responsible of the perpetuation of the arrhythmia. Also the role of the triggering foci has been highlighted. To cure AF by means of non pharmacological therapy we may eliminate and/or modify the substrate. To better understand the mechanism underlying the AF and to choose the best ablation strategy is of fundamental importance to map the right and the left atrium during AF. Our experience shows that in chronic idiopathic AF disorganized atrial activity is observed at all atrial regions while in paroxysmal idiopathic AF the left septum and the right atrial posterior areas are highly disorganized while the lateral region shows more organized atrial electrical activity. Multipolar basket catheters are extremely useful in mapping right and left atrium in order to guide the best ablation strategy.

Atrial Fibrillation↗
PubMed2000

Acute myocardial infarction in young adults: prognostic role of angiotensin-converting enzyme, angiotensin II type I receptor, apolipoprotein E, endothelial constitutive nitric oxide synthase, and glycoprotein IIIa genetic polymorphisms at medium-term follow-up.

BACKGROUND: A number of reports have investigated the association between various gene polymorphisms and the phenotypic expression of myocardial infarction. No investigations have evaluated the prognostic role of genetic factors in young people with premature coronary disease. The aim of this study was to investigate the influence of genetic factors compared with that of conventional risk factors on follow-up events in a population of Italian young adults with myocardial infarction. METHODS AND RESULTS: The study population consisted of 106 young patients (mean age 40 +/- 4 years, range 23 to 45 years) with diagnosis of acute myocardial infarction. Clinical and genetic data from the group of patients with events during follow-up were compared with those from patients without events. The following genetic polymorphisms were tested: angiotensin I converting enzyme, angiotensin II type I receptor, apolipoprotein E (ApoE), endothelial constitutive nitric oxide synthase, and platelet glycoprotein IIIa. Coronary angiography was performed in 94 patients. Coronary angiography showed coronary artery disease in 93% of patients. During follow-up (46 +/- 12 months, range 25 to 72) the overall combined end points (cardiac death, myocardial infarction, and revascularization procedures) accounted for 21 events. Family history of coronary artery disease, smoking, stenosis of the left anterior descending artery at coronary angiography, and ApoE polymorphism (presence of epsilon4 allele) were significantly more prevalent (univariate analysis) in the group of patients with events. Logistic multivariate analysis showed that ApoE polymorphism (P =. 004, odds ratio [OR] 6.8, 95% confidence interval [CI] 2 to 22), family history (P =.005, OR 8.3, 95% CI 2 to 35), smoking after acute myocardial infarction (P =.008, OR 10.9, 95% CI 2 to 62), and left anterior descending coronary artery disease (P =.02. OR 6.6, 95% CI 1.3 to 33) were independent predictors of adverse events. CONCLUSIONS: Myocardial infarction at a young age is commonly characterized by evidence of multiple cardiovascular risk factors and by a favorable prognosis in short- and medium-term follow-up. Evidence of significant disease at coronary angiography suggests the presence of a premature atherosclerotic process. ApoE polymorphism (presence of epsilon4 allele) appears to be a strong independent predictor of adverse events, suggesting a remarkable influence in the accelerated coronary disease.

Adult↗
PubMed1997

The effects of combined distension of the stomach and the descending colon on coronary blood flow in anaesthetized pigs.

The effects of the combined distension of the stomach and the descending colon on coronary blood flow were examined in seven alpha-chloralose anaesthetized pigs whilst preventing changes in heart rate and aortic blood pressure. Changes in coronary blood flow in the left circumflex or anterior descending coronary artery were assessed using electromagnetic flowmeters during distension with Ringer solution of balloons positioned in the viscera. In a first set of studies, graded distension of the stomach with distending volumes of 0.8, 1.1 and 1.4 l always caused graded decreases in coronary blood flow. The additional distension of the descending colon at a distending volume of 0.25 l augmented the response of decrease in coronary blood flow caused by the first two levels of gastric distension, but it did not have any further effect when added to the higher level of gastric distension. Similar results were obtained in a second set of studies in which distension of the stomach at a volume of 0.8 l was additionally performed during graded distension of the descending colon with distending volumes of 0.25, 0.35 and 0.45 l. These effects elicited by combined distension of the two viscera were not affected by the administration of propranolol, but they were abolished by subsequent administration of phentolamine. The results showed that combined distension of the stomach and the descending colon in anaesthetized pigs augmented the reflex response of coronary vasoconstriction and that the response to distension of one viscus was attenuated during increased levels of distension of the other viscus. These combined responses to distension of the two viscera involved efferent sympathetic mechanisms related to alpha-adrenoceptors.

Adrenergic alpha-Antagonists↗
PubMed1993

Left ventricular dysfunction following transient ischaemia induced by transluminal coronary angioplasty. Beneficial effects of calcium antagonists against post-ischaemic myocardial stunning.

Acute and severe ischaemia is followed by depression of myocardial contractility during reperfusion; return to full recovery might take a long time. This phenomenon, termed myocardial stunning, has been extensively demonstrated in experimental studies and in different clinical settings. The beneficial effects of calcium antagonists in preventing post-ischaemic myocardial stunning have been tested in experimental studies, showing that when administered before or during ischaemia, they inhibit post-ischaemic myocardial dysfunction. The present study was undertaken to verify the possible occurrence of myocardial stunning following transient ischaemia induced by coronary angioplasty. The aim was also to evaluate the possible protective effects of calcium antagonists (nisoldipine) and nitrates against myocardial stunning in patients with coronary artery disease undergoing routine coronary angioplasty (PCTA) with prolonged inflation. The study included 25 patients, aged between 40 and 69 years, with exercise-induced angina and single vessel disease. The stenosis was severe (80% to subtotal occlusion), localized on the left anterior descending artery, but without collaterals at coronary angiogram. All patients had normal left ventricular (LV) overall function and normal systolic thickening of the anterior wall supplied by the diseased artery. Our data suggest that post-ischaemic myocardial stunning is not only an experimental curiosity, but that it does occur in different clinical settings. Calcium antagonists (i.e. nisoldipine), when added before or during ischaemia, seem to prevent myocardial stunning. These findings confer a potential role to these agents in the treatment of post-ischaemic myocardial dysfunction.

Adult↗
PubMed1993

Noninvasive ultrasonic biopsy: evaluation of early arteriosclerotic lesions progression in normal asymptomatic, hyperlipidemic, and diabetic subjects.

Noninvasive ultrasonic biopsy (UB) is a method of detecting early arteriosclerotic changes by high-resolution ultrasound scanning of the carotid and femoral bifurcation. Six UB classes (scoring 0 to 10) have been identified in 2000 asymptomatic subjects and 600 vascular patients followed up for four years. The incidence of silent coronary ischemia (tested by effort test) and the occurrence of symptomatic events in four years are increased in advanced classes and with increasing UB score. The rate of progression (ROP) in four years to the next UB class has been defined in normal subjects (1.4% in class I, 3.1% in II, 10.7% in III, 17.9% in IV, and 79.2% in class V). In a group of 305 asymptomatic hyperlipidemic subjects and in a group of 269 diabetics the ROP (in four years) was significantly higher. Therefore ultrasonic biopsy is useful to identify subjects at risk of coronary ischemia and cardiovascular events and to follow up noninvasively the progression of arteriosclerosis.

Adult↗
PubMed1993

[The clinical and echocardiographic parameters at rest and during mental arithmetic stress in preadolescent subjects with a hypertensive parent].

Previous studies have showed that a genetic predisposition and/or a family history of essential hypertension may play a significant role in the development of cardiovascular changes in borderline hypertensive patients. Moreover, mental stress has been identified as contributing to the development of cardiovascular disease. The aim of this study was to compare the possible changes in blood pressure and Doppler echocardiographic parameters in resting and during mental arithmetic stress in 21 children with a hypertensive parent (Group I) and 21 age-matched children with normotensive parents (Group II), similar for body mass index, alimentary and life habits, and not differing in resting blood pressure, heart rate and Doppler echocardiographic parameters. Mass index was slightly but not significantly high in Group I with respect to controls. During mental stress only in the children with a family history of hypertension there was a significant increase (p < 0.02) in systolic blood pressure. A positive relation between the increase in systolic blood pressure and end-diastolic thickness of interventricular septum and posterior wall was observed in the same group. In addition a close relation (p < 0.05) between mass index and end-systolic left ventricular stress at rest was evidenced, whereas a negative relation (p < 0.03) between the increase in systolic blood pressure on one side and the early peak diastolic filling velocity (Vmax E) and the ratio of early to atrial peak diastolic filling velocity (Vmax E/Vmax A), on the other side, were found.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

[Coronary angioplasty. Indications, diagnostic and indicative methods, follow-up results].

Coronary angioplasty (PTCA) represents a valid alternative to coronary artery bypass surgery (CABG) in several cases; moreover, PTCA might be performed, for myocardial revascularization, even in patients in whom CABG is transitory or definitely contraindicated. However, the guidelines for mechanical myocardial revascularization are still mainly based on clinical criteria and the only angiographic data should not be sufficient to extend the indications for PTCA. Despite the technical improvement of the procedure and the material used, PTCA continues to have two main limitations: the relatively high acute complications rate (4-7%) and long-term restenosis rate (20-40%). The advent of new techniques for myocardial revascularizations (transluminal atherectomy, coronary stents, laser angioplasty) might partially reduce these limitations.

Angioplasty, Balloon, Coronary↗
PubMed1993

[The myocardial protective effects of cardiac tissue ACE inhibition in experimental ischemia-reperfusion in isolated rat hearts].

The protective effects of captopril were evaluated in vitro on isolated perfused rat hearts after a global ischemia of 20 min. The hearts were randomly allocated in 2 groups. In the first one (n = 6) captopril was added at a concentration of 270 microM. The second one was utilized as control (n = 6). Aortic flow and minute work respectively decreased on reperfusion by 35% and 49% in captopril group and by 65% and 71% in controls (p < 0.001). No changes occurred in heart rate. Aortic systolic pressure and coronary flow decreased in the 2 groups, but not significantly. Myocardial enzyme release during reperfusion showed significant lower levels of CPK and LDH in the captopril group as compared to controls (p < 0.001 after 41 min). The occurrence of serious ventricular arrhythmias was considerably higher in controls with respect to the captopril group. Irreversible ventricular fibrillation occurred only in control hearts (50%). These data indicate that captopril exerts a protective effect during myocardial ischemia and reperfusion by preventing serious ventricular arrhythmias, reducing enzymatic release and a lower decrease in cardiac performance, without an increase in heart rate.

Animals↗
PubMed1992

Myocardial stunning following coronary angioplasty: protective effects of calcium-channel blockers.

The beneficial effects of calcium-channel blockers against myocardial stunning have been tested in experimental studies, showing that, when added before or during ischemia, a protective effect against postischemia stunning is achieved. The present study was undertaken to test and compare the protective effect of calcium antagonists [nisoldipine (NIS) and nifedipine (NIF)] and nitrates (NIT) against myocardial stunning in patients with coronary artery disease undergoing percutaneous transluminal coronary angioplasty (PTCA) with prolonged inflation as PTCA represents a model of induced acute and severe ischemia for a brief period and might cause myocardial stunning. The study included 30 patients between the ages of 42 and 67 years, all with exercise-induced angina and single-vessel disease, with severe stenosis (80% to subtotal occlusion) localized on the left anterior descending artery and with the absence of collaterals on the coronary angiograms. Moreover, all patients had normal left ventricular (LV) overall function, as well as normal systolic thickening of the anterior wall, supplied by the diseased artery. Patients were randomized to a pre-PTCA treatment with NIT, 80-120 mg/day (10 patients), NIF, 40-60 mg/day (10 patients), and NIS, 10-20 mg/day (10 patients). Pre-PTCA treatment was initiated 7 days before the procedure and continued after. During the PTCA, at the first balloon inflation, an additional dose of 300 micrograms of NIT was injected into the left anterior descending artery through the balloon catheter in the patients in the NIT group, as well as 0.2 mg of NIF in NIF group patients and 0.05 mg of NIS in NIS group patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗