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G Zanotto

Publications and source records attributed to G Zanotto.

8 recordsLinked to original sources
PubMed1995

Maximal myocardial perfusion by videodensitometry in the assessment of the early and late results of coronary angioplasty: relationship with coronary artery measurements and left ventricular function at rest.

In the assessment of the acute results of percutaneous transluminal coronary angioplasty (PTCA), myocardial perfusion at maximal vasodilatation theoretically has fewer limitations than the coronary flow reserve measurements and quantitative coronary angiography. The purpose of this study was to compare the myocardial perfusion to the measurements of the severity of the lesion (minimal luminal diameter and percent area stenosis) and to relate it to the changes of left ventricular function after PTCA. Regional myocardial perfusion was assessed during intracoronary papaverine, using the inverse mean transit time of contrast medium (1/Tmn), before, 15 min after, 18-24 hr after, and 6 months after successful single-vessel PTCA in 14 patients with stable angina. Left ventricular angiography (before angioplasty, 18-24 hr after, and 6 months later) was analysed by area-length and centerline methods. Immediately after PTCA, 1/Tmn increased from 0.14 +/- 0.07 sec-1 to 0.21 +/- 0.09 sec-1 (P = .001). Maximal myocardial perfusion remained higher than the pre-PTCA value the day after angioplasty (1/Tmn of 0.23 +/- 0.09 sec-1), while it reduced to near pre-PTCA values at follow-up (1/Tmn of 0.16 +/- 0.05 sec-1). Before PTCA, three out of ten patients had ejection fraction of < 65%, and seven had mild-to-moderate hypokinesis. The day after PTCA the ejection fraction and the regional dysfunction improved significantly. The change in ejection fraction 18-24 hr after PTCA did not correlate with minimal luminal diameter and percent area stenosis and correlated slightly with the improvement of perfusion (r = 0.54, P = .10). At follow-up left ventricular function deteriorated in the whole group, despite the persistence of angiographic success of PTCA, possibly because of changes in the loading condition. Coronary artery stenosis measurements and 1/Tmn failed to correlate with the left ventricular function. Given the difficulties in routine application of the analysis of time-density curves, the measurement of minimal luminal diameter remains a more practical assessment of the results of the intervention. However, the improvement of myocardial perfusion may give more information than coronary artery dimensions of the early recovery of left ventricular function.

Adult↗
PubMed1994

Coronary vasoconstriction in response to acetylcholine after balloon angioplasty: possible role of endothelial dysfunction.

BACKGROUND: Abnormal endothelium-dependent vasomotion has frequently been observed early after coronary angioplasty. The aim of this study was to investigate endothelium-mediated coronary vasomotion caused by increasing intracoronary infusions of acetylcholine into epicardial coronary arteries 3-6 months after coronary angioplasty in patients without restenosis (50% luminal diameter reduction). METHODS: Intracoronary acetylcholine was infused during follow-up coronary angiography followed by an intracoronary bolus of 250 g nitroglycerin in 18 patients who had undergone successful angioplasty of 21 isolated coronary artery lesions. Using an automated edge-detection program, coronary artery measurements were performed in the proximal reference segment, in the proximal part of the angioplasty site, at the site of previous maximal stenosis, in the distal part of the angioplasty site, and in the distal reference segment. RESULTS: In the segments of the coronary artery not manipulated by balloon catheter, acetylcholine did not produce significant luminal diameter changes (+2 +/- 23% in the proximal segment and -3 +/- 27% in the distal segment at 10(-4) mol/l). All the angioplasty vessel segments, excluding the proximal reference segments, showed an abnormal dose-related reactivity to the acetylcholine. Maximal vasoconstriction was observed at 10(-4) mol/l and was 4.9 +/- 11.1% in the proximal reference segment, 9.3 +/- 19.1% in the proximal angioplasty site (P = 0.0314), 20.3 +/- 24.1% at the site of previous maximal stenosis (P = 0.0005), 10.7 +/- 16.8% at the distal angioplasty site (P = 0.0098), and 9.3 +/- 14.1% in the distal reference segment (P = 0.0032). The maximal response of the angioplasty site to acetylcholine and to nitroglycerin did not correlate either with the time to follow-up or with the follow-up stenosis. Nitroglycerin-induced vasodilation was significant in all segments, but was lower in the lesion-related segments. Acetylcholine evoked the same effect on both the vessels that were manipulated and those that were not. CONCLUSIONS: Three to 6 months after coronary angioplasty, endothelium-dependent vasodilation was impaired not only at the site of previous maximal stenosis, but also in segments directly injured by balloon inflation. In contrast, endothelium-independent vasodilation by nitroglycerin is maintained in all segments. These observations suggest that the endothelium is still functionally impaired in the area of balloon dilation.

Acetylcholine↗
PubMed1994

Distribution of CII and CIII peptides in lipoprotein classes: methods and clinical significance.

We describe a method for measuring apolipoprotein (apo) C distribution between apo B-containing lipoprotein (apo B-LP) and non-apo B-LP. The procedure requires the precipitation of apo B-LP, the redissolution of the pellet, and the quantification of C peptides in the redissolved pellet. The ratio of apo C in non-apo B-LP to apo C in apo B-LP has been calculated for both CII and CII (R-CII and R-CIII, respectively). R-CII (0.49 +/- 0.25) and R-CIII (0.84 +/- 0.54) in patients on maintenance dialysis are significantly lower than in the control group (1.14 +/- 0.57 and 1.45 +/- 0.92, respectively), indicating that hypertriglyceridemia in these patients results from a reduced catabolism of triglyceride-rich LP (TGRLP). Patients with coronary artery disease (CAD) show a distribution of C peptides no different from the control group. Analysis of covariance reveals that the patterns of R-CII and R-CIII are not entirely predictable from the serum concentration of triglycerides. This result seems to support the hypothesis that the underlying metabolic defects involving TGRLP in dialysis patients are not the same as those in patients with CAD.

Adult↗
PubMed1993

[Endothelial dysfunction in ischemic syndromes].

Several studies have shown evidence of the key role of the endothelium in modulating the tone of epicardial coronary vessels, in the different manifestations of coronary artery disease. Recently, the role of endothelium-dependent vasodilation has been focused, because clinical observations have suggested that myocardial ischemia might be caused or aggravated by inappropriate vasoconstriction of resistance vessels. An abnormal endothelium-dependent vasodilation, either of epicardial and of coronary microvasculature, has been documented in patients with syndrome X and in patients with history of hypertension and left ventricular hypertrophy. Vasoconstriction of the small coronary vessels is probably the mechanism underlying the impaired increase of coronary blood flow during atrial pacing and the wide variations of the ischemic threshold in some patients with chronic stable angina. In patients with variant angina, the endothelial function seems abnormal only in the conductance vessels. It is likely that the endothelial dysfunction of the small coronary arteries be present in many clinical situations in which a discrepancy between a mild atherosclerosis of epicardial coronary artery and signs of ischemia exists, as it has been observed early after successful angioplasty and after coronary artery reperfusion during acute myocardial infarction.

Coronary Vessels↗
PubMed1991

[Angina due to anatomical anomalies and to functional changes in the epicardial coronary vessels].

Myocardial ischemia with normal coronary arteries can be due to anatomic or functional reasons. The more severe congenital coronary anomalies in the adulthood are the origin of the left main of the left coronary artery from the right aortic sinus, with a course between the aorta and the pulmonary trunk, and the origin of the left main from the pulmonary trunk. Both these anomalies can cause sudden death, usually associated with physical exertion. The coronary vasomotion of epicardial vessels depends on the interaction of several neurohumoral substances. We report the hemodynamic, angiographic and stress test data of 30 patients affected by chest pain, with myocardial ischemia and normal coronary arteries. In 8 patients the response of epicardial coronary arteries to intracoronary infusion of acetylcholine was evaluated.

Acetylcholine↗
PubMed1991

[Myocardial infarct and angiographically normal coronary arteries].

Myocardial infarction and normal coronary arteries is not a rare event in the ischemic heart disease. Even if the patients with acute myocardial infarction and angiographically normal coronary arteries represent a small percentage (reported incidence varies from 1% to 12%) of all patients with acute ischemic attacks, they might be useful to highlight the pathogenetic mechanisms of this syndrome. To improve the understanding of this clinical entity, we reviewed our experience of 18 patients with myocardial infarction and normal coronary arteries. They were compared with a control group of patients with similar clinical characteristics (gender, age, infarct location) and residual coronary artery stenosis. The myocardial damage was less extensive in patients without residual stenosis (peak CK-MB: 56.1 +/- 71.9 vs 126.5 +/- 87.9 IU/I, p < 0.05), with a better left ventricular function either global (ejection fraction: 64 +/- 11 vs 55 +/- 13%, p < 0.05) and regional (SD/chord: -1.36 +/- 1.20 vs -2.42 +/- 1.04, p < 0.02). These findings probably reflect a more prompt and complete reperfusion of the infarct related artery. Myocardial necrosis may occur without obstructive coronary artery disease by the interaction of multiple factors such as abnormal platelet aggregation, thrombus formation and localized or diffuse changes of coronary vascular tone.

Adult↗
PubMedDate not supplied

[Knowledge about HIV infection in a group of professional nursing students].

A confidential questionnaire was given to 241 students of the nursing school of a Milano Hospital to record the knowledge on HIV infection and their experience with HIV patients during their training in wards different from Infectious Departments. The results evidence a good level of knowledge, comparable to the italian young population (according to other studies) of the same age. Nursing students from the very beginning of their practical training, happen to care for asymptomatic HIV positive subjects, therefore the school should provide knowledge and information on the HIV infection before the beginning of the practical training.

Adult↗