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M C Morice

Publications and source records attributed to M C Morice.

70 records · Page 4Linked to original sources

[Contribution of new technologies to the management of acute complications of coronary angioplasty].

This retrospective study of 4,000 coronary angioplasty procedures performed between 1/1/87 and 31/1/92 was undertaken to assess the benefits of new therapeutic options (perfusion balloon catheter, temporary and permanent stenting, laser balloon angioplasty, cardiopulmonary bypass) in the management of major complications of angioplasty and to evaluate the results of emergency coronary bypass surgery. Angioplasty was performed before (1,000 angioplasties: Group 1) and after (3,000 angioplasties: Group 2) the introduction of these new techniques at the Centre cardiologique du Nord. Despite the increasing complexity of the clinical and angiographic features of the patients, the global results show a significant decrease in the rates of emergency bypass surgery (2.1% in Group 1 versus 0.7% in Group 2; p < 0.0015) and of periprocedural acute myocardial infarctions (1.8% in Group 1 versus 0.7% in Group 2; p < 0.015). The use of these new techniques in cases of acute complications of coronary angioplasty decreases the signs of ischaemia before surgery (61.9% in Group 1 versus 68.1% in Group 2; p < 0.05). Coronary bypass surgery was performed under haemodynamically stable conditions in all patients requiring the procedure in Group 2, enabling the surgeon to perform more complete revascularisation with implantation of the mammary artery in 50% of cases (9.5% of cases in Group 1; p < 0.001). The interval to emergency bypass surgery depends mainly on the rapidity of the operative decision in cases of failure of these new techniques.

Angioplasty, Balloon↗

[Value and limits of balloon laser-assisted angioplasty in the treatment of acute obstruction during percutaneous transluminal coronary angioplasty].

One of the problems of percutaneous transluminal coronary angioplasty is acute occlusion during the procedure, the main cause of serious complications and emergency coronary bypass surgery. Acute occlusion is generally related to severe intimal dissection and/or thrombosis. In animal experiments, it is possible to treat intimal dissection and dessicate thrombi by balloon laser angioplasty. Using this method, a programmed laser energy may be delivered to the arterial wall via a fiber optic system linked to a Nd:Yag laser during classical balloon inflation. This has been proposed for the treatment of acute coronary occlusion. Between September 1989 and August 1990, 923 patients underwent coronary angioplasty at the Centre Cardiologique du Nord. Peroperative acute occlusions occurred 52 times (3.9%) in 52 patients. Sixteen patients who were "candidates" for emergency coronary bypass surgery (residual stenosis > or = 75%; delayed flow; myocardial ischaemia) were treated by laser balloon angioplasty, 14 with success (87%). Two patients had to be operated as an emergency. There were no hospital deaths. The average follow-up was 4.7 months for the 14 non-operated patients. Systematic control coronary angiography was refused by 2 asymptomatic patients. In the other 12 patients investigated 1 to 17 months after the procedure, there were 10 restenoses (76%), 6 of which were treated by repeat angioplasty and 3 by coronary bypass surgery. These results show that balloon laser angioplasty is very effective in the treatment of peroperative acute occlusions, enabling emergency coronary bypass surgery to be avoided in 87% of cases, but it is associated with a very high restenosis rate which is difficult to accept.

Acute Disease↗

[Acute myocardial infarction: recent physiopathological data. 2: Left ventricular function].

Myocardial infarction is an anatomical and therefore functional amputation of some of the myocardial tissues. Moments after acute coronary occlusion, a cascade of metabolic, mechanical and electrical ischaemia related events is observed. Contraction stops and regional left ventricular akinesis (then dyskinesis) occurs in the zone at risk of irreversible myocardial damage. This is partially compensated by hyperkinetic motion of non-ischaemic myocardium. The degree of alteration of the global ejection fraction is the resultant of these akinetic and hyperkinetic wall motions. It is lower in cases of anterior myocardial infarction, of occlusion of the proximal segment of the left anterior descending artery and of multivessel disease. Its eventual outcome depends on coronary blood flow. If the artery responsible is recanalized early, the global ejection fraction stabilises or improves. When this does not happen, the global ejection fraction decreases. The end-diastolic volume, an indicator of left ventricular remodeling, increases in relation to the size of the infarct and to the persistence of coronary artery occlusion. The delay before the appearance of the first irreversible lesions, the rate of their propagation within the myocardial wall and the presence of reperfusion lesions are poorly understood factors in the clinical setting and influence the efficacy of methods of myocardial protection.

Coronary Disease↗

[Coronary angioplasty under extracorporeal circulation. Technique and experience of the Centre cardiologique du Nord].

Between May 1989 and April 1990, 21 patients, candidates for coronary angioplasty but with major left ventricular dysfunction, underwent the procedure using percutaneous cardiopulmonary support (CPS). All patients had one or more previous infarcts, severe angina, and 19 out of 21 had one or more episodes of cardiac failure. Angioplasty was carried out by the usual method, after establishing a percutaneous femoro-femoral CPS. Twenty-three procedures were performed and 22 successes were recorded without any complications (success = 95% per patient). There were no deaths, infarcts or emergency surgical referrals. Two patients required transfusion. The canulae were removed by compression. The only local complication was one case of deep vein thrombosis. The results of this short series suggest that myocardial revascularisation is possible with an acceptable risk in selected coronary patients with severe left ventricular dysfunction by coronary angioplasty with percutaneous cardiopulmonary support.

Adult↗

"High-risk" percutaneous transluminal coronary angioplasty with preventive intra-aortic balloon counterpulsation.

Between January 1987 and February 1988, 1,385 patients underwent percutaneous transluminal coronary angioplasty; 27 procedures were performed using prophylactic intraaortic balloon counterpulsation. Twenty-four patients had poor left ventricular function (EF less than 40%), and coronary dilatation was performed in arteries opposite to an occluded myocardial necrosis related vessel. In three patients of advanced age with distal stenoses and normal left ventricular function a multivessel dilatation was performed. Primary success rate was achieved in all patients. There were no deaths, myocardial infarctions or emergency bypass operations in the hospitalization period. During the follow-up (9 to 21 months) there were 2 deaths, 1 cardiac transplantation, and 6 restenosis with repeated dilatation. If revascularization is warranted, in high-risk patients, coronary angioplasty can be performed safely and successfully with protection by intraaortic balloon counterpulsation. However the long-term prognosis of these patients is complicated by the presence of other high-risk variables, such as advanced age or poor left ventricular function.

Age Factors↗

[Coronary angioplasty in the treatment of threatening extension of myocardial infarction].

Recurrent angina with reversible ECG changes within days of a myocardial infarction is a serious clinical entity associated with a high incidence of reinfarction and death. In this study, we report a one-year experience of the treatment and outcome of patients presenting early post-myocardial infarction angina. Out of 32 patients who underwent coronary angiography, 3 were treated medically, 4 were operated upon and 25 had coronary angioplasty at the same time as coronary angiography with a 100 p. 100 immediate success rate. Four early reocclusions were redilated successfully. While in hospital 3 of these 32 patients had myocardial infarct extension (very moderate in 2 cases with CPK less than 500 and a patent artery), and there was no death. During an 8-month follow-up period there were 3 late deaths and 2 reinfarctions; 4 patients were operated upon and 4 were redilated. Thus, angioplasty has a high success rate in early post-myocardial infarction angina, enabling most patients to get through an unstable phase. In some patients, however, the course of the disease is marred by secondary adverse events.

Adult↗

[A new procedure for the study and treatment of myocardial infarction in the acute phase: percutaneous coronary angioscopy].

The recent development of small diameter optical fibers, which are also very flexible allows us to realise percutaneous coronary angioscopy. First of all we visualized normal dog's arteries, bifurcations, origin of small branches; then we created and visualized intimal tears, dissections and experimental thrombi. The second part of this work consisted in applying this new technic in three patients who had an evolving myocardial infarction and an occluded right coronary artery. In all three cases a clot has been visualized, occluding the lumen of the artery. This small experiment shows that percutaneous angioscopy is a feasible, quick and save procedure. Its developments will be very important according to the development of percutaneous interventional therapies.

Animals↗

[Median-term course of left ventricular effects in aortic insufficiency. Echocardiographic study of 90 patients].

It is important to know the natural evolution of the changes in left ventricular dimensions and contractility in AR if one wishes to determine the critical echocardiographic values at which LV function starts to deteriorate. This was the aim of our echocardiographic study of 90 patients with chronic pure AR in whom we analysed the changes in LV dimensions, mass and contractility for 11 to 84 months (average 34.6 months). The patients were divided into 2 groups according to the degree of ventricular dilatation (delta DD): Group A: delta DD less than 30% (58 patients), Group B: delta DD greater than 30% (32 patients). The annual mean increase in diastolic and systolic LV dimensions and myocardial mass in each group was: 1.5 mm vs 3.2 mm (p less than 0.02); 0.9 mm vs 4.1 mm (p less than 0.003), 14 g vs 24 g (p = 0.07 NS) respectively. The parameters of the systolic function were normal in Group A (EF = 68 +/- 8% and % FS = 38 +/- 6%) and decreased in Group B (EF = 58 +/- 13%, % FS = 32 +/- 9%). A significant annual decrease of the mean values of these parameters was only observed in patients of Group B (EF = 1.8% per year; % FS = -1.2% per year). These results are on average of unequal individual variations: variations of DD or EF greater than the variability due to the reproducibility of the method were only observed in 43 patients. The number of patients in whom echocardiographic changes were observed was comparable in Groups A and B.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Echocardiography in chronic aortic insufficiency. Prediction of the reversibility of left ventricular dysfunction following surgical correction].

UNLABELLED: The long term outcome of patients undergoing aortic valve replacement (AVR) for chronic aortic regurgitation (AR) is mainly determined by the reversibility or permanence of left ventricular dysfunction. We analysed the echocardiogram of 49 patients before and after surgery to identify the patients whose left ventricular dysfunction regressed completely after AVR. The patients were divided into 2 groups according to the results of the last postoperative echocardiogram: Group I: 25 patients whose left ventricular dimensions and wall motion reverted to normal; Group II: 24 patients with dilated and/or hypokinetic left ventricles. The two groups of patients were comparable for sex (Group I: 19 men, 6 women; Group II: 20 men, 4 women), age (Group I: 50,8 years, Group II: 53,9 years) and length of postoperative follow-up (Group I: 32 months, Group II: 34 months). The following parameters were measured and compared: diastolic and systolic left ventricular dimensions, myocardial mass and ventricular wall motion. RESULTS: Patients in Group I had less left ventricular dilatation than those in Group II (+35% vs +60%, p less than 0,001) and left ventricular contraction was better (FE: 62% vs 45%, p less than 0,001; %FS: 35% vs 23%, p less than 0,001). This study establishes that patients with chronic AR and % delta Dd less than 60%, an EF greater than 50% or %FS greater than 25%, have about a 90% probability of normalisation of LV function after AVR. If one of the indices exceeds these threshold values, the probability of permanent LV dilatation and/or hypokinesia after AVR is also about 90%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗