Search PubMed⌕ Search

Biomedical subjects

M Pornin

Publications and source records attributed to M Pornin.

11 recordsLinked to original sources
PubMed1992

[Quantitative thallium myocardial tomoscintigraphy. Value of intravenous infusion of dipyridamole after negative submaximal exercise test].

Patients with suspected coronary artery disease are sometimes unable to exercise adequately (85% of age calculated maximal heart rate) to validate their ergometric stress test. Some groups suggest performing dipyridamole scintigraphy from the outset but then the information provided by exercise stress testing is lost. The aim of this study was to compare scintigraphies performed after exercise alone and after exercise combined with dipyridamole using a method of quantification. Thirteen patients with ischaemic heart disease without necrosis (coronary lesions greater than 75% luminal narrowing in: 7 right coronary, 10 left anterior descending, 3 left circumflex arteries and 1 left main coronary artery with 50% luminal narrowing) underwent exercise stress testing followed by Thallium imaging. One week later, the same exercise stress test was performed followed by an intravenous injection of dipyridamole and Thallium scintigraphy. The circumference of the radioactivity was traced and the surface of each segment calculated in three different short axis views, subdivided into 4 segments (anterior, lateral, inferior and septal walls). Any segment vascularised by a stenosed coronary artery was considered to be underperfused (105 segments). The ratios of the surfaces of underperfused/normal segments were compared using the two study protocols. Segments of the same wall in the 3 short axis views were grouped in the same myocardial zone. Thirty five myocardial zones were thus obtained: 25 zones were more underperfused after combining exercise and dipyridamole than after simple exercise stress (p = 0.014). The average increase in underperfusion after the combined exercise-dipyridamole was 12.4% compared with 5.5% after exercise alone (p = 0.03). Secondary effects were minimal.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Disease↗
PubMed1990

[Enoximone in the hemodynamic evaluation before heart transplantation. A new test].

A better selection of patients referred for cardiac transplantation should lead to better surgical results. The presence of severe and irreversible pulmonary hypertension is an important factor and its pretransplantation assessment requires pharmacodynamic testing with vasodilators and dobutamine. The aim of this study of 10 patients in congestive cardiac failure referred for cardiac transplantation was to evaluate enoximone in this indication by comparing it with sodium nitroprussiate (3 micrograms/kg/mn). Intravenous enoximone (total dose of 1.5 mg/kg) increased the cardiac index (+49%; p less than 0.01), slightly reduced the mean systemic blood pressure (-8%; p less than 0.05) whilst inducing a greater reduction in systemic arterial resistances (-36%; p less than 0.01); the fall in mean blood pressure was less than with sodium nitroprussiate (-23%; p less than 0.01). Myocardial oxygen consumption (rate-pressure product) did not increase in contrast to the effect of dobutamine (+21%; p less than 0.01). There was a significant reduction in pulmonary arteriolar resistances (p less than 0.01) with all three drugs but the interpretation of this response and its prognostic significance in patients with a low cardiac output and persistent pulmonary hypertension are discutable even when pulmonary arteriolar resistances are less than 6 Wood units. The value of using an inotropic agent such as Dobutamine or Enoximone is to unmask fixed pulmonary hypertension which may be missed in patients with low cardiac output even with vasodilator drugs, and also to mimic the haemodynamic result of transplantation. In this indication Enoximone may be used like Dobutamine but with the advantage of not increasing myocardial oxygen consumption and being probably less arrhythmogenic.

Adult↗
PubMed1990

[Phosphodiesterase inhibitors].

Phosphodiesterase III inhibitors constitute a new therapeutic group for congestive cardiac failure. They inhibit the degradation of cyclic adenosine monophosphate and increase the intracellular calcium. They have a double inotropic and vasodilator haemodynamics occurs without any increase in the myocardial effect. The improvement in the consumption of oxygen. The beneficial haemodynamic effect seems to last over a medium period of time, but the survival in the long term treatment is not yet known.

Electrophysiology↗
PubMed1988

[Short-axis thallium 201 tomography. Changes in the isotope fixation on the circumference of the left ventricle].

Several authors have studied variations in myocardial thickness on short-axis sections cut through healthy postmortem hearts. The circumferential profiles showed a series of minima and maxima, with a minimum at the septum, a maximum at the anterior interventricular junction and another at the anterolateral papillary muscle, a minimum at the inferior wall followed by a maximum at the posterior papillary muscle, then at the posterior interventricular junction, after which came a septal minimum again. When examined by short-axis thallium 201 tomography, the left ventricle does not look like a ring of even density. The purpose of this study was to try and explain the changes in density observed by variations in thickness and to devise a quantification method that would take anatomical features into account. 23 patients with normal coronary angiography underwent thallium 201 scanning after exercise. Circumferential profiles were drawn from short-axis sections with the angle on the abscissa and the number of sections on the ordinate. 29 other patients with a more than 75 p. 100 stenosis of coronary vessels (anterior interventricular artery 15, right coronary artery 10, circumflex artery 8, diagonal artery 4) had the same examination. The circumferential profiles of normal subjects closely resembled those of anatomical sections, with a minimum at the upper and anterior septal wall (the limit between the two areas being undefinable), a maximum at the anterolateral papillary muscle and adjacent myocardium, a minimum at the inferior wall and a maximum at the posterior papillary muscle and adjacent septum. These curves enabled us to determine the relative perfusion values of one area compared with another, which will serve as reference.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Disease↗
PubMed1986

[Abnormal origin of the left coronary artery. Pre- and postoperative hemodynamic and metabolic studies].

The authors report the case of an asymptomatic 45 year old man in whom an abnormal origin of the left coronary artery was discovered fortuitously. Coronary angiography was carried out for electrocardiographic signs of anterior myocardial infarction and showed the left coronary artery arising from the pulmonary artery: there was apical dyskinesia with alteration of global left ventricular function. The ostium of the left coronary artery was closed and a saphenous vein aorto-left anterior descending artery bypass was performed. There were no complications. Left ventricular function has not improved 8 months after surgery. The haemodynamic and coronary signs of myocardial ischaemia demonstrated preoperatively regressed after surgery: the coronary "steal" caused by the malformation which led to poor perfusion of the territory of the left coronary artery has therefore been corrected by surgery. This procedure should be carried out as early as possible in order to limit extension of the myocardial lesions.

Coronary Artery Bypass↗
PubMed1985

[Myocardial infarction with normal coronary vessels in young subjects. Apropos of 2 cases with an interval of 2 months in 2 brothers aged 32 and 34].

The authors report 2 cases of myocardial infarction with normal coronary arteries occurring at an interval of 2 months in 2 brothers aged 32 and 34. Following an episode of angina, the younger brother, a sportsman, but a smoker, developed an antero-septal infarct at rest, which was complicated by complete persistent right bundle branch block. Ventriculography and coronary angiography were normal. Induced spasm tests were not performed. The elder brother presented an infero-apico-lateral infarct on effort, without any prodromal syndrome, which was complicated by apical akinesia. Ventriculography revealed mitral prolapse. Coronary angiography was normal and the methylergometrine test was negative. In relation to this example of familial infarction with normal coronary vessels, the authors review the features of this type of infarction reported in the literature which predominantly occurs in young people. They discuss the principal points of interest, including the incidence, the criteria of definition based on the coronary angiography, the elements of the prognosis, the pathophysiological mechanisms and the possibility of a genetic predisposition.

Adult↗
PubMed1985

[Intravenous labetalol in normotensive coronary patients. Effects on hemodynamics and myocardial metabolism].

The haemodynamic and myocardial metabolic effects of intravenous Labetalol were studied in 7 normotensive coronary patients with at least one significant stenosis on the left anterior descending artery. The study consisted of 5 successive observation periods: basal (I); during atrial pacing at the theoretical maximal heart rate or when anginal pain occurred (II); return to basal conditions (III); 20 minutes after an injection of 1.5 mg/kg of Labetalol over 3 minutes into the pulmonary artery (IV); during repeat atrial pacing at the rate achieved during phase II (V). There was no significant difference between phases I and III except for a slightly faster heart rate in phase III. The effects of Labetalol were assessed by comparing the results during phases III and IV between phases II and V and by analysing the variations between phases I, II, IV and V. In comparison with basal conditions (phase III), Labetalol (phase IV) induced a slight decrease in cardiac output (p less than 0.05), a decrease in aortic pressure and systemic arterial resistances (p less than 0.01) and of the double product. Coronary sinus flow did not change but myocardial oxygen consumption fell by an average of 11% (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

[Current aspects of infectious endocarditis. Review of 101 cases].

One hundred and one cases of infectious endocarditis were reviewed, from 1966 to 1982. The mean age of the patients was 56.3 +/- 15 years. There was a marked predominance of men (70.2 p. 100); the commonest portal of entry was dental (45.9 p. 100); the number of iatrogenic portals of entry and cases of endocarditis on prosthetic valves has been increasing in recent years. Blood cultures were positive in 83 p. 100 of cases; the commonest responsible organism was the non-D streptococcus (31 p. 100 of cases) followed by the D streptococcus (18.8 p. 100), the staphylococcus aureus (17.8 p. 100), and the staphylococcus epidermidis (2.9 p. 100). Gram-negative bacilli were isolated in 9.9 p. 100 of cases. Rare and slow growing organisms have been isolated since 1977. Echocardiography was then introduced and helped the diagnostic in 70 p. 100 of cases. Circulating immune complexes were measured in 25 patients and were found to be raised in 14 cases (56 p. 100). The commonest complication was cardiac failure (43 p. 100) which led to valve replacement in the acute phase in 14 p. 100 of cases. The occurrence of cardiac arrhythmias was a poor prognostic factor. The other complications were neurological (15 p. 100), renal (10 p. 100), embolic (19 p. 100), and pulmonary (9 p. 100). The mortality rate in the acute phase was 30 p. 100 and the probability of a five year survival was 54 p. 100.

Adult↗