PubMed Health⌕ Search

Biomedical subjects

J M Lablanche

Publications and source records attributed to J M Lablanche.

At least 127 records · Page 7Linked to original sources
PubMed1990

Percutaneous coronary rotary ablation.

The rotablator is a high-speed rotating ablative system developed to grind obstructing atheromatous material into fine particles. It consists of a rotating burr attached to a long, flexible driving shaft with a central flexible guidewire. The device rotates with a speed of 190,000 r.p.m. In this study, after appropriate pretreatment, the atherectomy system was positioned over the guidewire, the steerable guidewire advanced to beyond the stenosis, the abrasive burr positioned at the stenosis and the rotation commenced. The abrasive burr was advanced until a resistance was experienced and then, with back and forth motion, further advanced until passage of the stenosis was achieved. The procedure was repeated six to eight times until no further mechanical resistance was encountered. Patients were maintained on aspirin and nifedipine. With a burr size between 1.5 and 2 mm, in 32 patients in the right coronary artery, twelve patients in the left anterior descending artery and eight patients in the circumflex artery, an average increase in diameter from 0.52 +/- 0.28 mm to 1.27 +/- 0.37 mm was achieved with respective reduction in the stenosis from 80 +/- 11% to 47 +/- 17%. Balloon dilatation was subsequently carried out in 19 patients in 15 of whom residual significant stenosis was due to the use of an inadequately large burr. There were no deaths. During ablation, in six patients evanescent (of few seconds in duration), spontaneously-reversible AV-block developed probably due to embolization of particles into the sinus node artery. Two patients developed coronary spasm, three had acute occlusion with subsequent myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Prospects in the treatment of stenosis of the coronary arteries].

Treatment of stenosis of coronary arteries has progressed considerably since the introduction of angioplasty by Grüntzig. There are three problems associated with angioplasty: reocclusion, restenosis and extension of indications. To solve these problems, a good many techniques designed to flatten or destroy the plaque have been developed. Hemoperfusion balloons can be used to treat reocclusion by prolonged inflation and may reduce the rate of restenosis. Methods for assisting blood circulation (CPS or hemopump) extend the indications for angioplasty to inoperable patients. Stents hold the vessel open and hence prevent reocclusion. They can be useful for stenosis of shunts but in general are thrombogenic and have not proved efficacious in preventing restenosis. Laser-heated metal probes (hot tips) generate spasm and thrombosis. Lasers are now used to heat balloons which allow reattachment of grafts and reduction of restenosis. The excimer appears more promising. Atheroma is currently the subject of some interest and atherectomy has proved feasible, but the indications are as yet undefined. Although new techniques have introduced the possibility of treating certain reocclusions, none has proved effective in prevention of restenosis. The multiplicity of instruments currently available allows gradual extension of the indications for angioplasty.

Angioplasty, Balloon, Coronary↗
PubMed1989

Percutaneous coronary rotational angioplasty in humans: preliminary report.

Percutaneous coronary rotational angioplasty was attempted in 12 patients. The procedure was performed with a flexible rotating shaft with an abrasive tip, varying in diameter from 1.25 to 3.5 mm, tracking along a central guide wire. Among the 12 patients (mean age 58 years), 4 had a stenosis in the left anterior descending coronary artery and 8 a stenosis in the right coronary artery. After the guide wire crossed the stenosis, the abrasive tip was slowly advanced and several passes across the stenosis were made. The residual stenosis was measured with computerized automatic quantitative coronary angiography. Success was defined as a reduction of percent stenosis by greater than 20%. If residual stenosis remained significant (greater than 50%), the procedure was completed by balloon dilation. The device could not be inserted in 2 of the 12 patients. Five of the 10 patients underwent rotational angioplasty alone, and 5 had the procedure completed by balloon dilation. The stenosis was significantly enlarged from 0.56 +/- 0.31 mm to 1.26 +/- 0.28 mm. The outline of the vessel appeared smooth and regular. There were no complications related to the procedure and all patients were free of symptoms when discharged 2 to 3 days after the procedure. Thus, coronary rotational angioplasty is a simple and safe procedure allowing marked dilation of the narrowed segment. However, long-term follow-up is required for further evaluation.

Aged↗
PubMed1989

Relation to restenosis after percutaneous transluminal coronary angioplasty to vasomotion of the dilated coronary arterial segment.

Among 868 patients with successful percutaneous transluminal coronary angioplasty (PTCA), 437 were restudied angiographically and had a provocative test with ergonovine during coronary angiography performed before and 6 months after the procedure. The relation between provoked coronary artery spasm and restenosis was studied and 4 groups of patients were analyzed. Those in group 1 (n = 63) had spasm before and after PTCA and their rate of restenosis was high (55%), especially when spasm after PTCA was observed on the dilated coronary segment (restenosis rate 58%). Patients in group 2 (n = 78) had spasm before PTCA but without abnormal vasoconstriction at 6 months and their incidence of restenosis was 19%. Sixty-one patients in group 3 had no spasm before PTCA but developed spasm at restudy. The rate of restenosis was high (38%) in this group, especially when the spasm after PTCA was located on the dilated segment (43%). In group 4 (n = 235), patients had no spasm before or after PTCA and the restenosis rate was 20%. Thus, the presence of coronary artery spasm on the dilated coronary segment, 6 months after a successful PTCA, is frequently accompanied (43% in group 3 and 58% in group 1) by restenosis.

Angioplasty, Balloon↗
PubMed1989

Percutaneous aspiration of a coronary thrombus.

Right coronary artery occlusion by a thrombus occurred during the coronary angiography performed in a patient with anterior myocardial infarction. Emergency coronary aspiration was undertaken via a 9F guiding catheter, which allowed the thrombus to be removed. The patient, who was in cardiogenic shock, immediately improved and was subsequently discharged without any complications or sequelae.

Angiography↗
PubMed1989

Abnormal diffuse coronary vasomotion.

Although coronary artery spasm and abnormal vasoconstriction have undergone considerable investigation, it remains difficult to assess coronary vasomotor tone. To address this problem, the combination of two pharmacological tests (IV injection of 0.4 mg ergometrine followed 5 min later by IV injection of 3 mg isosorbide dinitrate) was performed after the routine procedure of coronary arteriography. Two indexes were defined: total coronary vasomotion (TCV) and maximal total coronary vasomotion (max TCV). These indexes were measured in 20 normal subjects and the normal values were 28.2 +/- 14% and 50.8 +/- 19.2% respectively. Among the 2758 patients who underwent the two tests, a group of 40 patients with normal coronary arteries, no focal spasm and diffuse abnormal coronary vasomotion (DAV) was identified. Eleven patients had vasoconstriction and vasodilatation within the normal range and were identified only by the combination of the 2 tests. All the 40 patients complained of angina at rest and three had had a previous myocardial infarction in the area supplied by the vessel with DAV. During a spontaneous episode of pain at rest 7 patients had ST segment elevation, and 7 a T wave inversion. Thus, these indexes of total coronary vasomotion could be useful to identify patients with abnormal vasomotor tone which could not be detected by the conventional provocative tests.

Adult↗
PubMed1989

[Cross-over double-blind study of verapamil versus diltiazem in effort myocardial ischemia].

There is a number of factors in favor of a different effect between the two main calcium-blockers causing bradycardia. The effects of 3 doses of verapamil 120 mg and 3 doses of diltiazem 60 mg, were compared in a double-blind study with cross-over, in 12 patients with coronary insufficiency diagnosed by coronary angiography. Four stress tests were performed in each patient, two with placebo before each treatment period and two after treatment, according to the Bruce protocol, using a computerized ECG reading system. As compared with the placebo, the two products decrease the myocardial oxygen needs, increase the duration of the stress and improve the baseline offset of the ST segment. The ischemia, demonstrated by the baseline offset of the ST segment, appears significantly less with verapamil than with diltiazem.

Coronary Disease↗
PubMed1988

Left ventricular systolic and diastolic function during acute coronary artery balloon occlusion in humans.

Left ventricular function during percutaneous transluminal coronary angioplasty was studied in 16 patients undergoing the procedure. All measurements were performed before and during the first episode of balloon coronary occlusion. In 16 patients (Group A), data were recorded before and 30 or 50 s after balloon inflation, and in 8 of these patients (Group B) data were also recorded 15 min after the complete procedure. Left ventriculograms indicated a marked dyskinesia of the anterior and apical wall in all patients. After balloon inflation, there was a marked depression in stroke index and ejection fraction and an increase in left ventricular end-diastolic pressure and the time constants of relaxation in all patients. Simultaneous recording of left ventricular pressure (Millar micromanometer) during cineangiography permitted the assessment of myocardial and chamber stiffness. Although there was a strong tendency for both myocardial and chamber stiffness to increase after 30 to 50 s of occlusion, these increases were statistically insignificant. In Group B, a third set of angiographic and pressure measurements obtained 15 min after completion of the coronary angioplasty procedure indicated no residual left ventricular dysfunction, and in this respect, the results are of added clinical importance.

Angioplasty, Balloon↗
PubMed1988

[A new method of laser angioplasty by contact sapphire: preliminary results. Apropos of 20 cases].

We report our first 20 cases of peripheral laser angioplasty using an optic fibre with contact sapphire tip. The equipment included a teflon catheter on which was screwed a round sapphire 2.2 mm in diameter. A 600 microns optic fibre connected to a Nd-Yag laser instrument was introduced into the catheter and placed in contact with the sapphire. Twenty patients underwent recanalization of femoral or popliteal arteries occluded on a length of 5 to 45 cm. The sapphire-tipped catheter was introduced by the Seldinger technique up to the site of occlusion. The 15 watt laser emission was set at intervals of one second. Sixteen out of the 20 occluded arteries were recanalized. Among the 4 failures, 3 were due to perforation and 1 to intraparietal progression. Angioplasty was performed with laser alone in 3 cases and with laser completed by balloon catheter in 13 cases. The minimum diameter of the laser-induced channel was 2 mm and was significantly increased (3.8 mm) by complementary balloon dilatation. In the 3 patients who underwent laser angioplasty alone, no noticeable improvement in distal blood flow was demonstrated by doppler velocimetry, and reocclusion occurred either soon afterwards (n = 2) or later (n = 1). Midterm results were much better in patients who had had additional balloon dilatation: early (3rd day) or late (2 months) reocclusion took place in only 3 patients. In the remaining 10 patients, followed up for periods of 1 week to 18 months (mean: 6 months), clinical improvement and recanalization were maintained.

Angioplasty, Balloon↗
PubMed1988

[Reproducibility of the exercise test and coronary vasomotor tonus].

The effect of coronary vasomotor tone on exercise test reproducibility was evaluated in two groups of patients. All had an apparently stable angina, a positive first exercise test and at least one significant stenosis at coronary arteriography. Group A patients (n = 30) had a positive ergonovine test (dynamic stenosis) whereas this test was negative (fixed stenosis) in group B patients (n = 29). Patients of both groups underwent two exercise tests without treatment, each of these tests being performed on a different day of the same week, at the same time and according to Bruce's procedure. The reproducibility of angina was poor in group A patients: 6/15 (40 p. 100) as against 18/20 (90 p. 100) in group B patients (p less than 0.05). Moreover, the initially positive exercise test subsequently become negative in 6 of the group A patients and in none of the group B patients (p less than 0.05). The time elapsed before ischaemia appeared was globally increased to the same extent in both groups, but individual variations were more pronounced in group A: a more than 1 minute variation was noted in 63 p. 100 of group A patients and in 18 p. 100 of group B patients (p less than 0.01). Similarly, the double product of ischaemia (-1 mm) varied by more than 20 p. 100 in 37 p. 100 of group A patients and in 14 p. 100 of group B patients. In contrast, the maximum stress parameters were increased to the same degree in both groups, including the double product duration.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗
PubMed1988

[Congenital aneurysm of the coronary arteries. Apropos of 2 cases].

Two cases of aneurysm of the coronary arteries were diagnosed by coronary angiography in the course of a myocardial infarction. The first aneurysm was located at the level of the left coronary trunk in a 32 year-old woman; it was complicated with a massive anterior infarction which led to a heart transplant in the following months. The second aneurysm was located on the right coronary artery in an 18 year-old man; the inferior infarction was rudimentary and the subsequent course was quite favorable. Congenital aneurysm of the coronary arteries is a rare anomaly, often localized on the left coronary trunk and almost always diagnosed in young patients following myocardial infarction.

Adolescent↗
PubMed1987

Enhanced efficacy of computerized exercise test by multivariate analysis for the diagnosis of coronary artery disease. A study of 558 men without previous myocardial infarction.

Multivariate analysis has been proposed to enhance diagnostic accuracy of the exercise test in coronary artery disease. To quantify the improvement given by multivariate analysis in comparison with ST segment depression alone during exercise test, 558 men without previous myocardial infarction were studied retrospectively. All the patients underwent a symptom-limited Bruce protocol with computer-averaged recordings in V5, aVF, V2. Coronary angiography was performed within the following 90 days. Prevalence of coronary artery disease (diameter narrowing of 50% or greater) was 0.56. Among 12 clinical and exercise parameters studied by stepwise multivariate analysis, five were found to reach the maximal accuracy: (1) exercise duration, (2) history of typical angina, (3) typical angina during the test, (4) age, (5) maximal heart rate. In comparison with ST depression, multivariate analysis significantly improves accuracy (74.6 vs. 66.8%, P less than 0.01) by increasing sensitivity (0.68 vs. 0.59, P less than 0.05) without affecting specificity (0.83 vs. 0.76, NS). Thus, in a group of men without infarction and a low prevalence of coronary artery disease, multivariate analysis with five easily collected variables is more accurate than ST segment depression alone during exercise. In addition, ST depression did not appear as discriminant as exercise duration for diagnostic purposes. This finding emphasises the importance of performing a symptom-limited exercise test.

Adult↗