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S Chierchia

Publications and source records attributed to S Chierchia.

14 recordsLinked to original sources
PubMed1992

99Tcm-MIBI single photon emission tomography (SPET) for detecting myocardial ischaemia and necrosis in patients with significant coronary artery disease.

The ability of 99Tcm-methoxyisobutylisonitrile (MIBI) single photon emission tomography (SPET) to detect myocardial ischaemia and necrosis was assessed in 56 patients (45 male, 11 female, aged 55 +/- 5 years), with clinically recognized ischaemic heart disease (IHD). All underwent coronary angiography (CA) and left ventriculography (LV). SPET images were obtained at rest and at peak exercise (Modified Bruce) 90 min after injection of 99Tcm-MIBI (650-850 MBq). Data were acquired in 30 min over 180 degrees (from 45 degrees RAO to 45 degrees LPO) with no correction for attenuation, using a 64 x 64 matrix. The presence of persistent (P) or reversible (R) perfusion defects (PD) was then correlated to the resting and exercise ECG and to the results of CA and LV. Of the 56 patients, 34 had reversible underperfusion (RPD), 46 persistent underperfusion (PPD) and 31 had both. The occurrence of RPD correlated well with the occurrence of exercise-induced ST segment depression and/or angina (27 patients of 34 patients, 79%) and with the presence of significant coronary artery disease (CAD) (33 of 44, 73%). In 45 of 46 patients (98%) PPD corresponded to akinetic or severely hypokinetic segments (LV) usually explored by ECG leads exhibiting diagnostic Q waves (42 of 46 patients, 91%). The scan was normal both at rest and after stress in four of 11 patients with no CAD, and in two of 45 patients with CAD. Finally, an abnormal resting scan was seen in seven of 11 patients with normal coronary arteries, of whom six had regional wall motion abnormalities.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Proarrhythmic activity of intracoronary endothelin in dogs: relation to the site of administration and to changes in regional flow.

The endothelium-derived peptide, endothelin, has been shown to exert powerful constrictor activity in both isolated and in situ coronary arteries. Recent in vitro data on isolated cardiac myocytes suggest that the substance might also possess electrophysiologic properties. We investigated the possibility that endothelin (ET-1) may exert proarrhythmic effects when infused selectively in the coronary circulation of open-chest-anesthetized dogs. Animals were instrumented for the measurement of left anterior descending (LAD) or left circumflex (LCX) coronary artery blood flow, left systolic ventricular pressure (LSVP), dP/dtmax, mean arterial pressure (MAP), and epicardial electrocardiogram (ECG; three leads). Data were recorded during infusion (2 min) of saline (n = 5) or increasing doses of endothelin (5-80 pmol/kg) given selectively in either the LCX (n = 10) or the LAD (n = 10). When infused into the LCX, endothelin produced a dose-dependent decrease in flow (40 +/- 23% at 80 pmol/kg, mean +/- SD, p less than 0.01) with a concomitant increase in coronary resistance and a decrease in dP/dtmax and MAP. ECG changes typical of myocardial ischemia paralleled the decrease in flow and culminated in ventricular fibrillation at the highest dose (80% of dogs). Endothelin caused similar hemodynamic effects when infused in the LAD, but fatal arrhythmias occurred for lower doses and for little or no change in coronary blood flow. Thirty percent of the animals died at 10 and 60% died at 20 pmol/kg, doses that induced only a moderate decrease (8 +/- 7 and 21 +/- 12%, respectively) in LAD total blood flow. Ventricular tachycardia always preceded ventricular fibrillation and death.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

[Coronary angioplasty in the presence of a myocardial bridge: a clinical case].

Percutaneous transluminal coronary angioplasty (PTCA) is a widely used technique of myocardial revascularization. The number of patients treated by PTCA is continuously growing in spite of its major drawback, represented by restenosis in approximately 30% of patients. We report here the case of a PTCA performed on a tight left anterior descending lesion in the presence of a muscular bridge involving the stenotic area. The procedure was completely successful by both the angiographic and clinical side. Good patency of the vessel with nearly complete disappearance of the lesion was confirmed at 6-month angiographic follow-up. In conclusion, the presence of a muscular bridge involving the stenotic area does not seem to represent a contraindication to PTCA.

Angina Pectoris↗
PubMed1978

Coronary vasospasm as a possible cause of myocardial infarction. A conclusion derived from the study of "preinfarction" angina.

To investigate the pathogenesis of myocardial infarction we undertook a systematic study of patients with angina at rest, a syndrome known to evolve frequently into infarction. Among 187 consecutive patients, 37 had infarction, all in the area that showed electrocardiographic changes during angina. In all 76 patients who underwent hemodynamic monitoring, 201thallium myocardial scintigraphy or angiography during angina, a vasospastic origin of the attacks was documented. In six patients with infarction shortly after these studies and in two in whom the infarction developed during hemodynamic monitoring or during angiography the onset of infarction was indistinguishable from the onset of anginal attacks. One patient in whom spasm was observed at the onset of infarction died six hours later; at post-mortem examination, a fresh laminar thrombus was found at the site of the spasm. After infarction, complete thrombotic occlusion of the branch shown to undergo vasospasm was documented in two patients by angiography.

Adult↗
PubMed1976

[Clinical coronarographic characteristics and pathogenetic mechanism of angina pectoris with s-t elevation (author's transl)].

The study of 46 patients with frequent anginal episodes characterized by S-T elevation (so called "variant angina pectoris") demonstrated that this type of electrocardiographic pattern does not characterize a homogeneous group of patients. In fact, while in some patients angina occurred only at rest, in others it occurred also on exercise. Sometimes ecgraphic alterations characterized by S-T depression were observed on the same leads which on other occasions had shown S-T elevation. The angiographic picture revealed: absence of significant coronary alterations in 10% of cases, stenosis greater than 75% in one main branch in 29%, in two branches in 39% and in three branches in 22% of cases. The hemodynamic monitoring carried out on 14 of these patients demonstrated that the ecgraphic modifications occur before the onset of the hemodynamic parameters which control myocardial O2 consumption. This suggests a primitive reduction of regional myocardial blood supply as a cause of the ischaemic episodes. The study of the regional myocardial perfusion with 201Tl technique in 6 patients confirmed this hypothesis. Coronary angiography carried out during an ischemic episode showed that the reduction of myocardial blood supply was caused by a spasm of a large coronary artery involving a long segment of the vessel, reversible by nitroglycerin administration. Aorto-coronary by-pass operation performed on 6 patients was followed by the disappearance of pain in two patients, even though the "by-pass" patency was angiographically proved in two patients.

Adult↗
PubMedDate not supplied

Psychological and physiopathological study on coronary patients.

In this paper the AA have tried to define the relationship between psychopathological characteristics or symptoms and angina attacks in coronary patients. The research plan was agreed upon and carried out as a collaborative program between psychiatrists and internists with the goal of reaching a more comprehensive approach to the psychosomatic patient. In 20 patients suffering from nocturnal angina attacks the polygraphic sleep recording was performed; 10 of them received psychodiagnostic examination (MMPI). In 8 cases during sleep recordings hemodynamic monitoring was also performed. The MMPI data were compared with 82 other individuals who had myocardial infarction (56 ss) and diurnal angina (26 ss) and 34 control subjects without cardiac disease. The results show that the sleep patterns were strongly affected and the most relevant alterations were recorded during the nights with ischemic episodes. No significant correlations were found between ischemic episodes and sleep stages. In no instance did the hemodynamic monitoring show an increase in the parameters related to myocardial oxygen consumption. The psychological data showed that the most severe symptomatology was observed in the nocturnal angina patients where the disease seems to be mostly related to a functional pathogenic mechanism.

Adolescent↗