Biomedical subjects

B Valeix

Publications and source records attributed to B Valeix.

At least 37 records · Page 2Linked to original sources

PubMed1985

Alternate ventriculo-atrial Wenckebach conduction during ventricular tachycardia.

Although pacing-induced ventriculo-atrial (VA) Wenckebach conduction has been previously described, the occurrence of this phenomenon during ventricular tachycardia has received little attention. The latter is defined as 2:1 VA block in which the conducted beats show progressive lengthening of VA conduction until the sequence is terminated by two or three blocked ventricular beats. This phenomenon was observed in a 16-year-old boy who underwent electrophysiologic study for ventricular tachycardia as a late complication of surgical correction of tetralogy of Fallot. During pacing-induced ventricular tachycardia with a morphology similar to that of the spontaneous tachycardia, 8:4 alternating VA block was observed. This sequence suggested that the AV node was the site of block, the 2:1 block being located at the upper level, and the VA Wenckebach block at the lower level. Alternate VA Wenckebach conduction appears as a possible cause of variation in atrial depolarization intervals during ventricular tachycardias with short cycle lengths.

Adolescent↗

PubMed1985

[Immediate coronary angioplasty in the acute phase of myocardial infarction. French multicenter study: December 1983].

Following the introduction of intracoronary thrombolysis in the acute phase of myocardial infarction (AMI), transcutaneous coronary angioplasty (TCA) was originally conceived as a logical complementary procedure to treat residual stenosis and so prevent the frequent post-thrombolysis reocclusion (20-30 p. 100 of cases). With increasing experience TCA of first intent appeared rational, more rapid and effective, ensuring coronary recanalisation (CR), suppression of residual stenosis and the prevention of reocclusion in the same procedure with with the objective of reducing the number of coronary bypass grafts (CBG) in patients with single vessel disease. A French multicentre study of 22 cases was organised by 9 centres. The average period between onset of symptoms and intervention was 2 hours 10 mins (range 30 mins-5 hours 30 mins). The average duration of the procedure was only 30 mins. 16 patients had anterior and 6 patients inferior AMI. Coronary angiography showed 12 occlusions (54.5 p. 100) and 10 sub-occlusions with 6 cases of delayed opacification. All patients had successful initial TCA with no major complications. The arterial occlusions decreased from 100 p. 100 to 31 p. 100 and the subocclusions from 94 to 12 p. 100. 2 patients died in the hospital period, one at the 48th hour of controlateral AMI and the other one at the 5th day of reocclusion. Three patients developed reocclusion at the site of the original TCA. Complete regression of ECG changes was observed in 31.8 p. 100 of cases. Complete recovery of normal left ventricular function was observed in 8 of the 17 patients who underwent follow-up investigations (47 p. 100 of cases).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1985

[Coronary occlusion immediately following a successful coronary angioplasty. Treatment by repeat angioplasty].

The authors report the case of a 52 year old patient with a significant stenosis of the medial portion of the left anterior descending artery (LAD) with excellent left ventricular function. Transluminal coronary angioplasty (TCA) was indicated following a positive exercise stress test. This was initially performed successfully. Fifteen minutes after the end of the procedure, a total obstruction occurred at the site of dilatation immediately eliciting significant precordial chest pain and massive elevation of the ST segment. Isosorbide dinitrate (ISDN) at a dose of 2 mg was injected into the artery 3 times without success as was an attempt to pass through the obstruction with a guide wire. Another TCA was then attempted without administration of the thrombolytic agent. The dilating catheter passed easily by the obstruction permitting several dilatations which restored rapid coronary artery flow, relieved completely the chest pain, and normalized electrocardiographic abnormalities. This procedure represents a new therapeutic approach to obstruction, an often unpredictable and serious complication of coronary angioplasty in the absence of collateral circulation, thereby preventing the development of a myocardial infarction and an emergency aortocoronary bypass operation.

Acute Disease↗

PubMed1985

[Long-term effects of transluminal coronary angioplasty. French multicenter study].

Although transluminal coronary angioplasty is now acknowledged as an effective treatment for coronary artery disease, the long-term outcome of patients treated by this method is still under evaluation. A french multicenter trial was set up and the long-term efficacy of transluminal coronary angioplasty was assessed in 546 patients undergoing the procedure before the 31/3/83. 380 initial successes (69 p. 100) were followed up for a period ranging from 6 to 48 months (average 19.9 +/- 10.4 months). A control coronary angiography was carried out in 88 p. 100 of cases. Restenosis (loss of over 50 p. 100 of initial angiographic improvement) was observed in 27 p. 100 of cases. Including the repeat procedures, the patency rate of the dilated vessels was 82 p. 100. Progression of atherosclerosis on another coronary artery was observed in 1.3 p. 100 of cases. After transluminal coronary angioplasty, 72 p. 100 of patients remained improved, 11 p. 100 underwent repeat angioplasty, 8 p. 100 underwent coronary bypass surgery, 1.3 p. 100 suffered myocardial infarction and 1.3 p. 100 died. Restenosis was associated with recurrence of angina pectoris in 90 p. 100 of cases (within 3.3 +/- 1.6 months) and a positive exercise stress test in 87 p. 100 of cases. Recurrence of angina due to progression of disease on the dilated vessel was observed in 24.2 p. 100 of cases; repeat transluminal coronary angioplasty was carried out for this indication in 38 p. 100 of cases, coronary bypass in 34.8 p. 100 and medical treatment was continued in 27.2 p. 100 of cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗

PubMed1985

[Complications of transluminal coronary angioplasty. A multicenter French study (1983)].

The authors report the complications observed during 1 247 transluminal coronary angioplasties (TCA) performed in 1 187 patients in 17 french centers between 1979 and October 1983. There were 855 primary successes (68.9 p. 100). There were 41 cases of symptomatic dissection (3.3 p. 100) of which 32 underwent aortocoronary bypass surgery with a residual myocardial infarction (MI) in 13 cases (40.6 p. 100). Medical treatment of symptomatic dissection gave very poor results (7 out of 9 MI) and is formally contra-indicated. 67 per- or postoperative occlusions were observed (5.3 p. 100). This is the most serious complication which necessitates an emergency revascularisation procedure (TCA or coronary bypass surgery--CBS--) because MI rapidly follows in patients without a well-developed collateral circulation. In this series MI occurred in 28 out of 45 patients--62 p. 100--despite CBS. This underlines the value of an immediate repeat TCA which, when successful, results in a much faster revascularisation. Seventy-three MI (5.8 p. 100) were observed in the first 24 hours: 50 p. 100 were secondary to an angiographically documented coronary occlusion. The other two causes were coronary dissection and spasm. Emergency CBS was carried out in 107 cases (8.9 p. 100) mainly for coronary occlusion or symptomatic dissection. The mortality was 11 out of 1 187 patients (0.93 p. 100). Death occurred in the catheter laboratory in 3 cases, during the first 24 hours in the operating theatre in 1 case, and after the first 24 hours but before hospital discharge in 7 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗

PubMed1985

[Treatment of recurrent ventricular tachycardia with hydroquinidine. Evaluation of its efficacy with electrophysiological technics].

Electrophysiological investigations were used to test the efficacy of dihydroquinidine chlorhydrate (600 or 1 200 mg/day) in a prospective study of 18 patients with recurrent ventricular tachycardia documented by electrocardiography. These patients did not respond to an average of 3.1 +/- antiarrhythmic drugs, including amiodarone in 12 patients. Hydroquinidine was well tolerated in 17 patients but had to be withdrawn in 1 patient because of hypotension. The effect of hydroquinidine on ventricular tachycardia induced by programmed pacing was evaluated after a 48 to 72 hours treatment, 3 to 5 hours after the last dose. After hydroquinidine it was not possible to induce ventricular tachycardia in 10 patients (58.8%). In the other 7 patients, it was possible to induce a ventricular tachycardia under treatment. In one case, hydroquinidine aggravated the arrhythmia as the induced tachycardia had a shorter cycle. In the other patients, hydroquinidine lengthened the tachycardia cycle by an average of 94 +/- 79 ms. The right ventricular refractory period increased cycle by 44 +/- 23 ms. Long-term hydroquinidine was prescribed for 7 patients, twice in association with amiodarone. Relapse was observed in 2 patients, 1 and 5 months after the onset of treatment. Five patients were well controlled by the treatment. The results of this study demonstrate the efficacy of hydroquinidine for the prevention of tachycardia induced by stimulation and underline its value in the treatment of sustained, recurrent ventricular tachycardia. This study illustrates the illustrates the importance of electrophysiological techniques for the identification of patients likely to benefit from a given antiarrhythmic treatment.

Adult↗

PubMed1985

[Supraventricular tachycardia induced by effort and by catecholamines].

The role played by catecholamines in the initiation of certain forms of ventricular tachycardia is now recognised. On the other hand, a similar predominant or exclusive mechanism has not been demonstrated in supraventricular tachycardia. We observed a rate case of reproducible attacks of junctional tachycardia on effort in a 45 year old man. This patient had experienced attacks of tachycardia on effort for a number of years, stopping about 10 minutes after the end of effort. An exercise stress test performed for an anginal attack, induced a narrow complex tachycardia at 270/min at the first minute of the recovery period which terminated spontaneously 18 minutes later after a brief episode of atrial fibrillation. During a second exercise stress test, an episode of tachycardia at 250/min was recorded at the second minute of recovery, lasting 11 minutes. Investigations showed a retrograde concealed septal bundle of Kent activated retrogradely during reciprocating tachycardia. A similar form of tachycardia was induced by an injection of isoproterenol. The adrenergic mechanism of the arrhythmia led to the prescription of a beta-blocker (propranolol 120 mg/day), which effectively prevented clinical tachycardia and the forms of tachycardia induced by ergometric tests 15 days and 3 months after the initiation of treatment.

Cardiac Catheterization↗

PubMed1985

[Treatment of recurrent ventricular tachycardias using oral propafenone].

The effect of oral propafenone on prevention of pacing-induced ventricular tachycardia (VT) was studied in 11 patients. All patients experienced documented sustained VT refractory to 4.1 +/- 2 antiarrhythmic agents per patient including amiodarone in 8. Programmed electrical stimulation was performed before and 48-72 hours after oral propafenone (900 mg/day) 2-3 hours after the last dose. Two patients developed spontaneous incessant VT before the scheduled date of the study on propafenone, and were classified as aggravation. Propafenone prevented pacing-induced VT in 2 patients (successful results). In 3 additional patients the results were partial, as non-sustained VT was induced on propafenone whereas sustained VT could be provoked during the control study. In the remaining 4 patients, oral propafenone failed to prevent pacing-induced VT. Tachycardia cycle length increased in 3 (C = 284 +/- 129 P = 450 +/- 202 ms) and was shorter in 1 aggravation. The 5 patients with successful or partial results (45.4 p. cent), underwent long-term therapy with a mean follow up of 5.6 +/- 4 months. Recurrence of VT occurred in 2. The remaining 3 are well controlled. This study demonstrates that propafenone is able to prevent pacing-induced VT in a limited number of patients. Stimulation techniques are useful in order to detect patients with potential pro-arrhythmic effect.

Administration, Oral↗

PubMed1984

Bepridil for recurrent sustained ventricular tachycardias: assessment using electrophysiologic testing.

Bepridil was found to possess electrophysiologic properties common to class I and IV antiarrhythmic agents. Intravenous and oral bepridil were evaluated using serial electrophysiologic studies in a selected group of 9 patients with recurrent sustained ventricular tachycardia (VT) unresponsive to usual therapy, including amiodarone therapy in 15 patients. Intravenous bepridil treatment terminated sustained, well tolerated, pacing-induced VT in 3 of 6 patients and prevented the initiation of VT in 2 of these and in a patient in whom the drug failed to restore sinus rhythm. Oral bepridil was administered at a loading dose of 800 mg on day 1, and 500 to 600 mg the following days, and programmed electrical stimulation was repeated 2 to 6 days after initial study. Oral bepridil therapy prevented VT initiation in 6 patients (66%). The tachycardia cycle length was prolonged (30 to 105 ms) in 2 patients in whom VT remained inducible. In 1 patient the tachycardia cycle length significantly shortened after bepridil and prompt cardioversion was required. Five of the 6 patients with successful results underwent long-term oral treatment with bepridil. VT recurred in 1 patient during the hospitalization period and an adverse effect (paralytic ileus) in another patient required drug discontinuation. Three patients remain symptom-free over a follow-up of 4 to 13 months. These data suggest that bepridil may be useful in patients with recurrent, sustained VT.

Administration, Oral↗

PubMed1984

Selective coronary arteriography by percutaneous transaxillary approach.

Coronary angiography by the percutaneous femoral approach is widely used. This technique is potentially dangerous or impossible in patients with advanced arterial disease of the lower limbs, whether or not surgically treated. In these cases, percutaneous left or right axillary approach is an alternative to brachial approach. In this article, we report our multicenter experience involving 120 patients. The left axillary artery was used in 94 cases (78%) and the right in 26 cases (22%). We used performed coronary catheters usually associated with the femoral approach. The left axillary artery was used preferentially since this avoids catheterization of the innominated trunk and allows easier catheterization of the coronary ostia and aortic ends of aorto-coronary bypass grafts. The routine use of a sheath (arterial introducer) avoided arterial compression during catheterization, prevented hemorrhagic suffusion when the catheters were exchanged, and reduced the risk of thrombosis or laceration of the axillary artery. There were no failures in the catheterization of the axillary artery and no complication was observed during or after the procedure. Axillary percutaneous technique appears to have the following advantages over the brachial arteriotomy: 1) Investigation time is equivalent to the time needed for the femoral percutaneous approach. 2) There is the possibility of lateral and simultaneous bi-plane angiograms. 3) Arterial puncture is preferable to arteriotomy. The axillary approach could also be used for percutaneous transluminal coronary angioplasty.

Adult↗

PubMed1984

[Coronary angioplasty immediately after intracoronary thrombolysis during the acute phase of myocardial infarction].

Since the introduction of intracoronary thrombolysis in the acute phase of myocardial infarction, all workers have observed a high incidence of coronary reocclusion (about 20%) essentially in the first hours and days after coronary recanalisation (CR). This had led to some groups carrying out transluminal coronary angioplasty (TCA) at the same time as CR by thrombolysis in situ to treat significant residual postthrombolysis stenosis. This french multicentre study carried out in 5 centres concerned 9 men (average age: 46.1 years) with 5 anterior infarcts (total thrombosis of the LAD artery) and 4 inferior infarcts (total thrombosis of the right coronary artery-RCA). Intracoronary trinitrate was ineffective in relieving the occlusion in all cases. In 5 cases, the thrombolytic protocol was streptokinase (SK) 3 000 u/min for 60 minutes; in the other 4 cases, the plasminogen-urokinase (Pg-UK) protocol was used. Thrombolysis was successful in all 9 cases. The results of TCA performed at the same time were also good (8/9 successes; 4 LAD and 4 RCA) without any complications during the procedure. There was only one immediate post-TCA reocclusion on a LAD artery. In all cases the initial ECG appearances of infarction remained, CR only appearing to prevent extension of the necrosis. The successful results of CR + TCA were maintained in 6 out of 7 patients reinvestigated 2 days to 6 months (average 6 months) after the initial procedure: the only case of reocclusion occurred after 48 hours on a RCA. The overall procedure never exceeded 2 hours.

Adult↗

PubMed1984

[Coronarography by percutaneous puncture of the axillary artery. Value in arteriopathies of the lower limbs].

Coronary angiography by a percutaneous femoral approach using the Judkins-Bourassa technique with special preformed catheters is widely used. This approach is potentially dangerous or impossible in patients with severe lower limb arteriosclerosis even after operation and so the investigation has to be done by Sones' technique (denudation of the humeral artery). There is, however, another upper limb approach which does not involve arterial denudation: percutaneous right or left axillary artery catheterisation. This paper reports the experience of a multicentre study of this method in 105 patients. This study is of interest as an arterial catheter introducer was used which, does not compress the artery, prevents bleeding when the catheter has to be changed and reduced the risk of thromboses or laceration of the axillary artery. 73 of the 105 patients had lower limb arteriosclerosis 5 had aortic aneurysms and 1 patient had a previous history of femoral artery embolism. There was a primary indication for this approach in 21 cases. The left axillary artery was used in 83 cases (79%) and the right axillary artery in 22 cases (21%). The coronary catheters were those usually used with the femoral approach. The left side was chosen preferentially as it avoided the brachiocephalic trunk and facilitated the catheterisation of the coronary ostia and of aorto-coronary bypass grafts. Selective catheterisation of the left coronary artery was achieved in 21 out of 22 cases (95%) and of the right coronary artery in all 22 cases (100%) by the right axillary route. Both left and right coronary arteries were selectively catheterised in all cases by the left axillary approach.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1984

[Accentuation of myocardial ischemia during coronary recanalization in the acute phase of myocardial infarction].

Coronary recanalisation during the acute phase of myocardial infarction, especially by in situ infusion of thrombolytic agents, is accompanied in most cases by rapid regression of chest pain and a reduction in the degree of ST elevation. However, a multicentre retrospective study of 104 attempts at recanalisation, including 78 successful procedures, showed in 10 cases (12.8 p. 100), an apparently paradoxical accentuation of the chest pain with or without increased ST elevation, at the time of angiographically demonstrable recanalisation. This phenomenon may be interpreted as being the result of aggravation of the ischaemia of the border zone, the objective of therapy. Several pathogenic hypotheses, all with experimental proof, may be suggested to explain these observations (haemorrhagic infarction, non reperfusion, ischaemic contraction due to massive intracellular flow of calcium, etc.). It is usually associated with arrhythmias and may be considered to be a reliable sign of recanalisation. It may also explain certain cases of persistence of chest pain and ECG changes despite the demonstration of a permeable epicardial artery on initial coronary angiography.

Coronary Angiography↗

PubMed1983

Retrograde (ventriculoatrial) conduction.

Interest in retrograde VA conduction has been renewed with the advent of tachycardias induced by physiologic pacemakers with atrial sensing capabilities. Accurate representation of ventriculoatrial conduction requires detailed electrophysiologic analysis during sinus rhythm, during tachycardias whether or not associated with accessory pathways, and during ventricular pacing studies. Retrograde conduction should be assessed in patients considered for implantation of atrial sensing and tracking pacemakers (VAT, VDD, DDD), until technologic advances overcome the problems of endless loop tachycardias.

Atrioventricular Node↗

PubMed1983

[Unstable angina and single vessel stenosis of the anterior interventricular artery. Evaluation of the threatened myocardium. Therapeutic implications].

The authors report a special cases of precise evaluation of threatened myocardium during coronaro-ventriculography. Two elements provided this evaluation: 1) spasm in the tight stenosis of the middle part of the anterior interventricular artery with immediate left ventricular dyskinesia (EF: 37%, EDP/EVD: 1.74; EDV: 98 cc/m2). 2) Complete instantaneous recovery after injection of 2 mg of trinitrine into the left ventricle (EF: 69%, EDP/EVD: 4.33; EDV: 28 cc/m2). This loss, in the order of 50%, in the left ventricular function led us to perform an angioplasty (ACT) with success. A further clinical and angiographic stenosis, three months later, in this 72 years old patient with arteritis, led us to perform an aorto-coronary graft, rather than another ACT.

Aged↗

PubMed1983

[Coronary angioplasty immediately after coronary recanalization in the acute phase of myocardial infarct].

The author report the case of a 48 years old patient, admitted to hospital 3 hours and a half after an anterior myocardial infarct which was well tolerated. Coronary recanalization with urokinase-plasminogen removed the obstruction of the middle part of the anterior interventricular artery 1 hour and a half after the patient's arrival. Selective left coronary angiography demonstrated a narrow stenosis, in the order of 98%, in the proximal part of the AIV artery. Angioplasty was attempted immediately, in view of the ease with which the guide wire was passed through the initial thrombosis and the good haemodynamic tolerance. The residual stenosis was estimated to be 20% after the angioplasty and at the examination 48 hours later. The ECG on discharge from hospital showed a QS appearance in V1 to V3 with R in V4. An improvement in the ejection fraction (EF) and in the end-diastolic volumes was found: EF: 48% compared to 38%, EDV (cc/m2): 79 compared to 120. The clinical course at two months is very satisfactory, with no residual angina and a negative stress test. This special procedure, combining a double therapeutic catheterization, lasted 1 hour 50 minutes and allowed the progression of the myocardial infarction to be halted and also avoided a subsequent aorto-coronary graft operation.

Angioplasty, Balloon↗

PubMed1983

[Sequential double demand programmable stimulation in the treatment of resistant supraventricular tachycardia. Long-term results].

Asynchronous pacing at a rhythm slower than that of the tachycardia (underdrive) is an established procedure for the reduction of supraventricular tachycardia. Simultaneous or sequential stimulation depolarising two parts of the circuit (atrium and ventricle) has a greater chance of reducing the tachycardia than stimulation of a single chamber. Five patients with supraventricular tachycardia resistant to antiarrhythmic therapy were treated by sequential pacing in the underdrive mode. Electrophysiological investigations showed a bundle of Kent to be responsible for the ECG appearances of Wolff-Parkinson-White (3 cases) with retrograde conduction only (concealed WPW) in 2 cases. One patient was able to put a stop to his attacks by the application of a magnet over the pulse generator. In four patients, a newly designed pulse generator, based on this concept, was implanted with the property of automatic detection of tachycardia (defined as a heart rate faster than 150/min) triggering almost simultaneous pacing of the coronary sinus and right ventricle (sequential interval of 65 ms) in the asynchronous mode at 77 bpm. The results were reviewed with a follow up of 6 to 36 months. This pulse generator was shown to be effective in both the reduction and prevention of episodes of supraventricular tachycardia. Sequential double demand pacing is a valuable and useful method of treating reentrant tachycardias associated with the WPW syndrome or concealed Kent bundles. It provides an alternative to surgery when the effective refractory period of the Kent bundle is long. Present advances in the field of cardiac pacing will probably result in a widening of the indications for this mode of therapy.

Adult↗

PubMed1983

[Hemopericardium after coronary recanalization with streptokinase in the acute phase of myocardial infarction. Drainage and early aortocoronary bypass on the 4th day].

A case of hemopericardium after coronary recanalisation with streptokinase during the acute phase of myocardial infarction is reported, emphasising the value of routine daily echocardiography in all cases of intracoronary thrombolysis. The patient was a 48 year old man with a primary antero-lateral infarct in whom coronary angiography was performed at the 4th hour, showing total proximal obstruction of the left anterior descending artery. The streptokinase protocol of intracoronary thrombolysis was performed, resulting in recanalisation of the left anterior descending artery at the 30th minute. Improved left ventricular function and persistance of coronary patency were confirmed 14 hours after recanalisation. In the following days the patient showed signs of right ventricular failure with successive echocardiogrammes demonstrating an increasing pericardial effusion. On the 4th day, 600 ml of blood were drained surgically and aorto-coronary bypass carried out on the left anterior descending artery. This procedure maintained coronary patency and the improvement in left ventricular function. Several studies have shown that the hemorrhage of reperfusion only occurs in the zones of necrosis, and thrombolytics, especially streptokinase, may aggravate this condition.

Coronary Artery Bypass↗