Biomedical subjects

J M Lablanche

Publications and source records attributed to J M Lablanche.

At least 19 recordsLinked to original sources

PubMed1992

Prognostic value of changes in R-wave amplitude during exercise testing after a first acute myocardial infarction.

To investigate the prognostic value of exercise-induced changes in R-wave amplitude and their relation to other exercise and angiographic variables, 303 consecutive patients who underwent maximal exercise testing and coronary angiography within 2 months of a first acute myocardial infarction were studied. R-wave amplitude at peak exercise increased or was unchanged in 159 patients (57.4%) and decreased in 118 (42.6%). Increased R-wave amplitude was significantly related to underlying 3-vessel disease (p = 0.0001), the extent of ST-segment depression on exercise (p = 0.0001), and the time to 1 mm ST depression (p less than 0.05). Follow-up information was available in 285 patients (86.4%) at a mean of 4 +/- 1.8 years. Death from cardiac causes occurred in 25 patients (9%); 18 (6.5%) developed recurrent myocardial infarction, and 32 (11.6%) developed angina. Variables with a predictive value for cardiac death were maximal exercise heart rate (p = 0.0005), occurrence of exercise-related supraventricular arrythmia (p = 0.02), and number of diseased vessels (p = 0.02). R-wave changes had no predictive value. No variable had a predictive value for recurrent infarction. Maximal exercise heart rate (p = 0.02) and increased R-wave amplitude (p = 0.0001) were significantly related to the occurrence of angina at follow up. Exercise-related R-wave increases were associated with the presence of angina at follow-up, but had no predictive value for cardiac death or recurrent infarction; their association with subsequent angina appears to reflect an association with more severe underlying coronary disease.

Angina Pectoris↗

PubMed1992

Percutaneous transluminal coronary rotary ablation with Rotablator (European experience).

This study reports the results from 3 European centers using rotary ablation with Rotablator, a device that is inserted into the coronary artery and removes atheroma by grinding it into millions of tiny fragments. Rotary ablation was performed in 129 patients. Primary success (reduction in percent luminal narrowing greater than 20%, residual stenosis less than 50%, without complications) was achieved by rotary angioplasty alone in 73 patients (57%). An additional 38 patients (29%) had successful adjunctive balloon angioplasty. Thus primary success was achieved in 111 patients (86%) at the end of the procedure. Acute occlusion occurred in 10 patients (7.7%). Recanalization was achieved by balloon angioplasty in 7: urgent bypass grafting was undertaken in 2. Q-wave and non-Q-wave myocardial infarction occurred in 3 and 7 patients, respectively. No deaths occurred. Follow-up angiography was performed in 74 patients (60%). Restenosis, defined as the recurrence of significant luminal narrowing (greater than 50%) occurred in 17 of 37 patients (46%) who underwent rotary ablation alone, and 11 of 37 patients (30%) who had adjunctive balloon angioplasty. The overall angiographic restenosis rate was 37.8%. In conclusion, rotary ablation is technically feasible, and relatively safe in the coronary circulation. The low primary success rate reflects the limited size of the device, which can be introduced through available guiding catheters, and limits the use of rotary ablation as a stand-alone procedure to lesions in small arteries or in distal locations. No reduction in restenosis was seen, but the role of this device combined with balloon angioplasty in larger arteries needs to be further defined.

Adult↗

PubMed1992

Clinical characteristics and angiographic follow-up of patients undergoing early or late repeat dilation for a first restenosis.

OBJECTIVE: The aim of this study was to analyze the angiographic rate of recurrent restenosis in patients who underwent repeat coronary angioplasty for a first restenosis within 3 months or greater than 3 months after the first procedure. BACKGROUND: Several studies that have examined risk factors for restenosis after coronary angioplasty have suggested that a short interval between a first angioplasty and a repeat procedure is associated with an increased risk for a second restenosis. METHODS: Between January 1981 and December 1990, 423 patients underwent a repeat coronary angioplasty procedure because restenosis had occurred at the site of a successful first angioplasty procedure. The clinical characteristics, immediate outcome and angiographic rate of recurrent restenosis were compared in patients who underwent repeat dilation within 3 months (early redilation group, n = 77) or greater than 3 months (late redilation group, n = 346) after the first procedure. RESULTS: The incidence of unstable angina at the time of the repeat procedure was significantly higher in the patients who underwent early redilation (42% vs. 8%, p = 0.0001). The procedural success rate (95%) and complication rate were similar in both groups. Follow-up angiography was performed in 86% of patients with an initially successful procedure. The incidence of restenosis was significantly higher in the group that underwent early redilation (56% vs. 37%, p = 0.007) and was similar in patients in this group who presented with stable (55%) or unstable (57%) angina. CONCLUSIONS: Rapidly recurring coronary stenoses have an extremely high rate of restenosis when again treated by coronary angioplasty, irrespective of the clinical presentation at the time of repeat dilation. The outcome in patients with early restenosis who have stable angina might be improved by delaying the repeat procedure.

Angioplasty, Balloon, Coronary↗

PubMed1992

Proto-oncogene expression in rabbit aorta after wall injury. First marker of the cellular process leading to restenosis after angioplasty?

In order to study the earliest phenomenons occurring in the arterial wall after balloon angioplasty, the level of expression of the proto-oncogenes, c-fos and c-myc, was studied in rabbit aorta after balloon denudation by using Northern blot analysis. Both c-fos and c-myc are rapidly and transitorily induced (maximal at 30 min and 2 h after mechanical injury for c-fos and c-myc respectively). By comparison, infusion of norepinephrine increases oncogene expression in normal non-denuded rabbit aorta after 1 h, but the combination of both mechanical and hormonal stimuli do not lead to a more important induction than balloon denudation alone.

Angioplasty, Balloon↗

PubMed1992

Prevention of coronary spasm by nicorandil: comparison with nifedipine.

The efficacy of nicorandil was compared with that of nifedipine in 13 patients with vasospastic angina enrolled in a randomized, placebo-controlled, crossover study. All patients had a coronary spasm during coronary arteriography, either spontaneously or ergometrine-induced. During two consecutive periods of 2 days, patients received active drugs or placebo in a randomized order. Each patient received single oral doses of 30 mg nicorandil, 10 mg nifedipine, and, on 2 days, a placebo. One hour after drug intake, patients underwent an ergometrine test with increasing doses of Methergin (ergometrine) (0.05, 0.10, 0.20, and 0.40 mg every 5 min). After placebo, the tests always were positive, and the ECG changes occurred at the same +/- 1 dose of ergometrine in 10 cases, showing good reproducibility. After nicorandil, the tests were negative in nine patients and positive for a higher or lower dose of ergometrine in three and one patient, respectively (p = 0.0034 vs. placebo). After nifedipine, the tests were negative in five patients and positive for a higher or the same dose of ergometrine in four and four patients, respectively (p = 0.0039 vs. placebo). Nifedipine (10 mg) and nicorandil (30 mg) were equally effective in eight patients; in the remaining five patients, nicorandil had better results (p = 0.06). Nicorandil (30 mg) prevents ergometrine-induced coronary spasm. This compound may be beneficial in patients with vasospastic angina.

Administration, Oral↗

PubMed1992

Dose-response curve of angiographically smooth human epicardial vessel segments to intracoronary injections of isosorbide dinitrate.

The coronary vasodilator properties of isosorbide dinitrate are well established but the doses generally used (1,000-2,000 micrograms) are still empirical. We studied, with the use of quantitative coronary arteriography (CAESAR System), the response of smooth vessel segments (greater than 1.85 mm diameter), preconstricted with methylergometrine (400 micrograms i.v.), to intracoronary injections of graded doses (5-100 micrograms) of isosorbide dinitrate and the effects of these injections on systemic hemodynamic parameters in 10 patients undergoing diagnostic coronary angiography. Six further patients, in whom the injections of isosorbide dinitrate were replaced by equivalent volumes of normal saline, served as controls. Relative to the diameter 5 min after injection of methylergometrine, the diameter increased by a mean +/- SD of 9 +/- 7, 26 +/- 12, 33 +/- 15, 38 +/- 14, and 39 +/- 16% after injections of 5, 15, 60, 240, and 1,000 micrograms, respectively, of isosorbide dinitrate. After a cumulative dose of 80 micrograms, subsequent doses did not cause further significant increases in diameter. Injection of saline in the control group did not alter the coronary diameter. A significant fall in systolic arterial pressure, compared to the control group, occurred at a cumulative dose of 320 micrograms. The mean arterial pressure and heart rate were unchanged. Significant coronary vasodilation occurs with intracoronary doses of isosorbide much smaller than those currently employed. Cumulative doses of 320 micrograms or more cause systemic hemodynamic changes without producing additional coronary vasodilation. During interventional cardiac procedures, where systemic hypotension is undesirable, the use of smaller doses of intracoronary isosorbide dinitrate than currently employed may be feasible and should be investigated further.

Adult↗

PubMed1992

Effect of ketanserin on proximal and distal coronary constrictor responses to intracoronary infusion of serotonin in patients with stable angina, patients with variant angina, and control patients.

BACKGROUND: Serotonin, released by aggregating platelets, may contribute to or cause myocardial ischemia by constricting epicardial vessels. Experimental studies suggest that this constriction is mediated by two distinct serotonin receptor subtypes: 5-hydroxytryptamine1-like (S1-like) and 5-hydroxytryptamine2 (S2). METHODS AND RESULTS: To determine the relative contribution of S1-like and S2 receptors to the vasoconstrictor effects of serotonin, we studied the effect of ketanserin (0.75 mg, intracoronary), a selective S2 receptor antagonist, on the constrictor response of human coronary vessels to intracoronary infusions of serotonin. In control patients (n = 7), serotonin (10(-4) mol/l) caused significant (p less than 0.05) constriction only in distal segments, which was significantly (p less than 0.05) inhibited by ketanserin. In stable angina patients (n = 8), serotonin (10(-4) mol/l) caused significant constriction in proximal (p less than 0.01) and distal (p less than 0.01) segments, which was significantly inhibited by ketanserin in proximal (p less than 0.05) but not distal (p = 0.30) segments. In patients with variant angina (n = 3), epicardial occlusion at the site of preexisting stenoses in proximal locations occurred at infused concentrations of 10(-6) (one patient) or 10(-5) (two patients) mol/l. The infusion of the same concentration of serotonin after ketanserin again caused epicardial occlusion. CONCLUSIONS: Our results suggest that functionally important S1-like receptors that mediate vasoconstriction exist in the epicardial vessels of patients with stable or variant angina. Their activation, either at hyperreactive sites in patients with variant angina or in the distal epicardial vessels of patients with chronic stable angina, may contribute to or cause myocardial ischemia when serotonin is released after the intracoronary activation of platelets.

Adult↗

PubMed1992

[Treatment of first restenosis by recurrent angioplasty. Immediate results and angiographic follow-up after 6 months].

This report summarises the authors' experience of 421 patients treated for a first restenosis by repeat conventional balloon angioplasty with a high 6 months angiographic follow-up (84%). The immediate results were significantly less than those obtained during the same period with initial angioplasty procedures (94.5% success and 0.9% complications without any deaths during the hospital period). The 39.9% recurrent restenosis rate, on the other hand, is the same as observed after a first procedure. The risk factors of a second restenosis seem to be different from those of a first restenosis. A shorter interval between the first and second angioplasty (< 3 months) was associated with a 55% risk of restenosis compared with only 36% when the interval was > 3 months. Two operative factors were associated with a high risk of recurrent restenosis: a maximum inflation pressure > 7 atm and > or = 3 balloon inflations. These results seem to be important and should be taken into consideration when deciding on the management of patients presenting with a first restenosis.

Aged↗

PubMed1992

[Coronary angioplasty of multivessel coronary diseases. Apropos of 1664 procedures. Immediate results and results following 6 months].

Between 1980 and 1990, 1,664 coronary angioplasty procedures were performed in 1,307 patients (86.6% male) with multivessel disease. The average age was 57 +/- 3 years (range 29 to 83 years). There was a previous history of infarction in 40.1% of patients and 22.4% of the procedures were performed for unstable angina. Catheter and 58.2%, 1,220 double vessel and 444 triple vessel diseases. A total of 2,509 lesions were dilated (1.5 stenoses/patient). The primary success rate was 81.9% with 3.2% of infarcts and 3.5% emergency bypass procedures and a global mortality of 2%. The factors responsible for death in the acute and hospital phases were unstable angina, age > 70 years, and ejection fraction < 35%. Complete revascularisation was achieved in 14.3% of cases: the only predictive factor for complete revascularisation on multivariate analysis was double vessel disease. A 6 months clinical and angiographic control was obtained for 83.8% of controllable procedures (965 dilatations). The restenosis rate was 47.9%. Univariate analysis of the factors of restenosis identified clinical parameters (age > 58 years, triple vessel disease, diabetes and unstable angina), parameters related to the lesion (length of stenosis > 1 cm, percentage stenosis > 80%) and to the procedure (residual stenosis > 20%): 68.4% of patients with restenosis underwent repeat angioplasty with a significantly superior primary success rate 88.7% vs 81.9% of global successes (p < 0.001). With a 82% primary success rate with few major complications, coronary angioplasty is a safe and effective therapeutic alternative. The extent of the lesions and the presence of chronic occlusion are the main limitating factors of revascularisation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

[Abnormal origin of the left circumflex coronary artery: clinical, angiographic and prognostic aspects. Apropos of 30 cases].

The object of this study of 30 patients with an anomalous origin of the left circumflex coronary artery was to define the clinical and angiographic features of this condition and to assess its influence on morbidity and survival. The 30 patients were 24 men and 6 women with ages ranging from 29 to 76 years. An anomalous origin of the left circumflex coronary artery should be suspected when two angiographic signs are present: firstly, the visualisation of a spur of opacification in the 30 degrees LAO view of left ventriculography, present in 93% or our patients; secondly, during selective left coronary angiography in the transverse view, an ascular zone is observed where the normal left circumflex artery should be. Confirmation of the diagnosis depends on opacification of the left circumflex arising from the right anterior sinus of Valsalva with a separate (37%) or common (23%) orifice with the right coronary artery or arising from a proximal segment of the right coronary artery/(40%). Five patients (17%) had a significant stenosis of the anomalous left circumflex coronary artery but this was always associated with lesions of the other coronary narrowing was observed. Of these patients, one had electrocardiographic signs of myocardial ischaemia and no other cause apart from the anomalous origin of the left circumflex to explain this ischaemia. The 30 patients were followed up for an average of 6.1 +/- 3.9 years. During this period, 1 cardiac death, 1 infarction, 5 cases of angina, 4 coronary bypass procedures, and 6 coronary angioplasties were observed. Nine patients (30%) had no cardiac event during follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

[Coronary angioplasty after thrombolytic therapy].

Two strategic choices are available after thrombolytic therapy: an aggressive strategy with the objective of restoring blood flow in the coronary artery responsible for the infarction or a conservative strategy, In the aggressive strategy, there is some debate about the timing of coronary angiography: immediate coronary angiography with a view to angioplasty during the same procedure whenever technically feasible or only when the artery remains occluded after thrombolysis ("salvage" angioplasty); or deferred coronary angiography and angioplasty with the objective of preventing recurrence of ischaemia, performed during the hospital phase before the patient's discharge. Besides this aggressive strategy, some cardiologists prefer to adopt a conservative attitude which consists in only performing coronary angiography and eventual revascularisation when the patients develop ischaemia during follow-up either spontaneously or during stress testing. Several randomised clinical trials performed in recent years, (TAMI, TIMI 2A and 2B, European Study, SWIFT), have all shown that there was no significant difference in survival or global left ventricular function between patients managed "aggressively" and those managed "conservatively". However, these studies are open to criticism, especially in the light of recent data about associated medical therapy which reduces the incidence of complications, especially of reocclusion. This point should be emphasised as secondary studies on subgroups have shown that the benefits of the aggressive strategy were totally lost in patients who developed reocclusion but, conversely, the outcome was much better if the angioplasty was followed by long-term success.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗

PubMed1992

[Nitrate derivatives and coronary vasomotricity].

The action of nitrate derivatives on the coronary arterioles is weak and very short lasting which avoids the phenomenon of a coronary steal syndrome. Investigations of the epicardial coronary vessels require vasoconstriction stress tests, usually using ergometrine, and vasodilatation tests, mainly using isosorbide dinitrate (ISDN). The combination of the two tests allows evaluation of global coronary vasomotricity which is less than 100% variation of diameter. In coronary spasm, ISDN relieves the stenosis in less than 2 minutes in nearly all cases. An infusion of ISDN also prevents most cases of arterial spasm. In effort angina, it has been possible to demonstrate paradoxal vasoconstriction during exercise due to endothelial dysfunction. The direct action of nitrate derivatives on smooth muscle which is not endothelium dependent, prevents the vasoconstriction and increases oxygen supply during exercise.

Coronary Artery Disease↗

PubMed1992

[Response of coronary arteries to the intracoronary injection of isosorbide dinitrate. Dose-response curve].

The coronary vasodilator properties of isosorbide dinitrate (ISDN) are well known but the dosage remains empirical. The aim of this study was to construct a dose-response curve to ISDN with respect to vasoconstriction induced by ergometrine. The heart rate, aortic pressure and coronary angiography were analysed before and 3 and 5 minutes after I.V. injection of 0.4 mg of methylergometrine and 3 minutes after intracoronary injection of 5, 15, 60, 240 and 1,000 micrograms of ISDN in 10 patients with an average age of 53.2 +/- 10.8 years (ISDN group). Six other patients with an average age of 56.5 +/- 12.8 years comprised the control group and only received ergometrine. The coronary diameters were measured by quantitative coronary angiography using the CAESAR system of automatic contour detection. Three coronary segments with angiographically normal appearances and a resting diameter greater than or equal to 1.85 mm were analysed in each patient. With respect to the maximal constriction observed 5 minutes after the injection of methylergometrine, the percentage increase in coronary diameter was 9 +/- 7%, 26 +/- 12%, 33 +/- 15%, 38 +/- 14% and 39 +/- 16% after 5, 15, 60, 240 and 1,000 micrograms of ISDN respectively (p less than 0.005 vs control). A plateau effect was observed after a cumulative dose of 80 micrograms and administration of higher doses of 240 and 1,000 micrograms only caused mild nonsignificant additional increase in vessel diameter. In comparison with the control group, the systolic blood pressure only fell significantly with doses greater than 240 micrograms of ISDN (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Angiography↗

PubMed1992

[Stenosis of the common trunk of the left coronary artery: an unusual complication of percutaneous coronary angioplasty].

The recurrence of angina-type pain within a few months of successful coronary angioplasty usually indicative of a diagnosis of coronary re-stenosis. A control coronary artery angiograph sometimes eliminates this diagnosis by detecting a fresh coronary stenosis. The authors report a case of a tight stenosis of the left major coronary trunk a few months after angioplasty of the circumflex artery. The onset of a stenosis of this type leads to the discussion of the possible role of a traumatic lesion of the wall of the major trunk by the catheter-guide.

Adult↗

PubMed1991

Morphological changes of coronary stenosis after repeated balloon angioplasties: a quantitative angiographic study.

To study the sequential changes of an atherosclerotic narrowing after repeated balloon dilatation, we reviewed the coronary angiograms of 11 patients who underwent at least 3 percutaneous transluminal coronary angioplasties of the same coronary segment for two restenoses. No significant changes in reference and stenosis diameters were found when comparing the three successive stenosis, but lesion length and stenosis area progressively increased. The identification of these morphological changes after repeated angioplasties may be of interest in the management of recurrent restenosis.

Angioplasty, Balloon, Coronary↗

PubMed1991

[Vasomotor activity and coronary insufficiency].

Provocative testing has provided a method of evaluating the important role of vasomotor tone in coronary artery disease. The most sensitive test is the ergonovine (Methergin) test. This is a specific and reliable method of defining the clinical situations in which coronary spasm is common: --focal coronary artery spasm is mainly observed in resting angina alone or in association with effort angina. The prognosis of spasm is excellent with calcium antagonist therapy provided there is no other associated pathology such as left ventricular failure or triple vessel disease; --in the six weeks following myocardial infarction, focal coronary artery spasm is a common event: 20% of coronary angiographies. After six weeks, spasm is much less frequent. It does not influence the prognosis. This type of spasm is probably related to the scarring process; --coronary artery spasm is frequently associated with restenosis after coronary angioplasty, a process which is histologically related to proliferation of smooth muscle; --diffuse increase in coronary vasomotor tone is a much rarer pathology, perhaps related to global changes in vascular tone as its association with the Raynaud syndrome and with migraine would suggest. It presents clinically with resting angina and sometimes by typical Prinzmetal angina; --finally, vosomotor tone plays an important role in the daily life of coronary patients. Holter recordings for the detection of silent myocardial ischemia have shown episodes of myocardial ischemia at lower myocardial oxygen consumption levels than those usually recorded during exercise stress testing, which suggests a reduction in oxygen supply, that is to say coronary vasoconstriction. Changes in coronary vasomotor tone can modify the diameter of healthy coronary arteries by 100%.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Disease↗

PubMed1991

[Long-term prognosis after myocardial infarction. Value of exercise test compared to clinical features and coronarography].

The aim of this study was to identify the parameters of exercise stress testing with a predictive value of cardiac death after myocardial infarction and to determine their importance with respect to clinical and coronary angiographic data. Three hundred and three patients, average age 48.9 +/- 9.2 years, surviving primary myocardial infarction, underwent a symptoms-limited exercise stress test and coronary angiography four to seven weeks after infarction. The average follow-up period was 48 +/- 22 months. Eighteen patients (5.9%) were lost to follow-up. Global mortality was 11.6% (33/285) and cardiac mortality was 8.8% (25/285) including 14 sudden deaths (56%) and 17 deaths during the first three years of follow-up (68%). A univariable analysis identified the following parameters of exercise stress testing as predictive of cardiac mortality. The duration of exercise, the maximal rate-pressure product, inconclusive test, the maximal heart rate, and occurrence of supraventricular arrhythmias. Only the last two parameters remained significant after a discriminant analysis and their combination with clinical variables (age and ventricular fibrillation during the hospital phase) enabled accurate classification of 79% of patients, which was significantly better than when clinical features were used alone (p 0.01). On the other hand, adding the data of coronary angiography (number of diseases vessels, absence of an Ergometrine test) only moderately improved this score (82%, NS). This study suggests that the results of the post-infarction exercise stress test enables identification of patients with a low or, on the contrary, with a high risk of cardiac death. The prognostic value of this investigation is better than simple clinical evaluation, especially in stable or asymptomatic patients. In this selected group of patients, coronary angiography did not provide additional prognostic information.

Adult↗

PubMed1990

[Other techniques of arterial recanalization].

During the last few years several new instruments have been added to the armentarium of endovascular procedures. They are aimed at destroying atheromatous plaques and recalibrating the arteries. The plaque destruction techniques include atherectomy which may be directional (as with Simpson's Atherocath) and applicable only to very proximal vascular segments, or rotational, pulverizing the plaques with a bur. In this category are the flexible Auth's rotablator and Stack's transluminal extraction catheter (TEC) where planning is combined with extraction. To traverse complete occlusions, Kaltenbach's rotating guide increases the success rate, but its use must always be completed by conventional angioplasty. Vascular recalibration can be achieved by stents or heating balloons. Numerous types of stent are now available. The best known are the Medivent stent which is self-expansive and stents with expanding balloons, such as the Palmaz Schatz stent or the radio-opaque Wiktor stent made of tantalum. These stents require an important anticoagulant therapy. These technique have widened the limits of angioplasty by tackling stenoses that have long been regarded as inaccessible. They have also made it possible to treat a number of acute occlusions. On the other hand, none of them has yet proved effective in the prevention of restenosis.

Arterial Occlusive Diseases↗