Indications of coronary angioplasty and stenting in 2003: what is left to surgery?

UNLABELLED: For many years, coronary artery by-pass graft (CABG) remained the only effective treatment of multivessel disease compared to medical treatment. The first technical revolution was in 1977 when Gruentzig introduced balloon percutaneous transluminal coronary angioplasty (PTCA), the 2nd in the 90's with the developments of stents and antiaggregant protocols. The equipment for PTCA became more and more sophisticated, and the skill of cardiologists greater. In the 90's, interventional cardiology played a predominant role in revascularization as the number of CABG decreased at the same time, and emergency CABG for bail out almost disappeared (0% to 0.5%). Systematic stenting decreased the need for repeat revascularization to about 18-20% nowadays in the majority of centers, except in diabetic patients. Despite this fact restenosis remains the pitfall of angioplasty, mostly in diabetic patients presenting multivessel disease in which surgery with "all arterial grafts" gives good long term RESULTS: The first studies comparing PTCA and CABG are favourable to surgery (BARI), then late ones using stents (ARTS, ERACI 2) showed that stenting was at least equivalent to CABG, in terms of mortality or serious complications (major acute coronary events, MACE), despite a higher target vessel revascularisation (TVR) mainly due to restenosis in the angioplasty cohort. The same results are observed by stenting a high risk lesion as the unprotected left main stenosis can be, until then treated surgically. However, high volume centers studies treating by PTCA+stent the unprotected left main artery (LMA) shows that the 1 year survival rate is similar to surgery, but always related to a restenosis rate of 20% at 6 months in the stent group, which represents the only significant difference in terms of MACE; the new drug eluting stents lead us to expect, according to SIRIUS and TAXUS II studies, to reduce the restenosis rate, and by the way, the MACE could be dramatically lowered from 50% to 60%. Randomised studies would be necessary, but the extrapolation of the actual data, more particularly results of subgroups with a high risk of restenosis, diabetic patients and small vessels, lead us to think that stenting could come in first intention before surgery if TVR is significantly reduced. A complex anatomy, failed attempted chronic occlusion, several lesions on tortuous vessels, would remain the last surgical indication if CABG provides a more complete revascularization. The impact of these new drugs seems promising. However, we should await early results of studies in diabetic patients and bifurcations. But in high volume experienced centers, CABG indications would be reduced in the future to the technical pitfalls of stenting (complex or tortuous anatomy, chronic occlusions) or to the adverse additional cost of this device, unless reduction of restenosis or TVR could also cancel this extra cost. We expect randomised studies CABG versus stented angioplasty using drug eluting stents to confirm these preliminary data.

[Complete revascularisation of multivessel coronary artery disease during acute myocardial infarction. Results following hospitalization and after 30 months. Series of 86 interventions carried out with 167 multivessel disease patients; causes of failure]. / Revascularisation complète des patients multitronculaires en phase aiguë d'infarctus du myocarde. Résultats en fin de période hospitaliere et à 30 mois. Série de 86 cas effectués sur 167 patients multitronculaires consécutifs; causes d'échec.

This series studied 167 patients with multivessel disease, admitted consecutively for acute myocardial infarction (excluding cardiogenic shock), who underwent systematic angioplasty and stenting before the 12th hour of the culprit artery and the other vessels with >70% (QCA) angiographic stenosis, and followed up for a period of 8 to 68 months with an average follow-up of 2.5 years. The criteria of evaluation were: numbers of asymptomatic patients, deaths, new infarctions, residual ischaemias, cardiac failure, angioplasties or bypass surgeries. On admission, 43.1% of infarcts were anterior, 48.5% inferior or postero-inferior and 8.3% lateral wall infarcts. One hundred and twenty-two consecutive patients had double vessel disease and 45 has triple vessel disease. The failures of revascularisation of the culprit artery were excluded from the study. The feasibility rate of complete multivessel revascularisation in a single procedure was over half the cases (86 out of 167, 51.5%): 60.6% of double vessel disease and 26.9% of triple vessel disease, a simple favorable anatomical presentation being necessary to accomplish this objective. During the hospital period (30 days), 95.3% of patients who were completely revascularised remained totally asymptomatic, 2 (2.3%) had recurrent infarction, 1 (1%) had cardiac failure and 1 (1%) died of a non-cardiac cause. No cardiac deaths were observed in this series. Of the multivessel disease patients who could not be completely revascularised (N=81) (poor clinical state or complicated anatomical presentation), 83.6% were asymptomatic: there were 7.7% cases of cardiac failure, 2.4% of recurrent infarction; 1.2% died of non-cardiac causes and 1.2% died of a cardiac cause. The statistical difference was significant in favour of the patients who had successful complete revascularisation with respect to the others in terms of numbers of asymptomatic patients (p=0.004) and of numbers of cardiac failure (p=0.002). The follow-up rate of patients who had complete revascularisation in a single procedure was 98.8%. After two and a half years of follow-up, 74.1% of patients were totally asymptomatic; the cumulative major cardiac adverse event rate (death, infarction, angioplasty or bypass surgery) was 29.4% and the reoperation rate by angioplasty or bypass surgery was 27%.

[Primary angioplasty associated with systemic coronary stenting in acute myocardial infarction. Results at the end of the hospitalization period and at 24 months]. / Angioplastie primaire associée à la mise en place systématique d'une endoprothèse en phase aiguë d'infarctus du myocarde. Résultats en fin de période hospitalière et à 24 mois.

A series of 149 consecutive patients admitted for myocardial infarction (excluding cardiogenic shock), dilated and systematically stented in the acute phase before the 12th hour and followed up for a period from 30 days to 2 years, was studied. The criteria of follow-up were: number of asymptomatic patients, deaths, reinfarction, residual ischaemia, cardiac failure, angioplasty or bypass surgery. On admission, 40.9% of the infarcts were anterior, 44.3% inferior and 14.8% lateral. One hundred and eighty-three stents with a diameter of over 3 mm were inserted. The angioplasty success rate was 98.6%. During the hospital period, 90.6% of patients were asymptomatic. 4.7% had recurrent infarction, 4% had cardiac failure, 0.7% had residual ischaemia, and there were 0.7% of cardiac deaths. The survival rate was 97.2% at 2 years: 69.8% of patients were totally asymptomatic: the cumulative major cardiac event rate (death, reinfarction, angioplasties or bypass graft) was 25.9% and the reoperation rate on the culprit vessel was 20.1%. These results show the short and long-term value of angioplasty associated with coronary stenting over other techniques in the acute phase of infarction based on the criteria studied. The long-term results of larger randomised studies using glycoprotein inhibitors (Gp IIb IIIa) associated with angioplasty and stenting are expected for validating the use of these products.

[Coronary artery stenting without antivitamin K. Results after a month]. / Implantation de prothèses endocoronaires sans antivitamine K. Résultats à un mois.

This paper reports experience with a new antithrombotic agent prescribed to reduce the incidence of subacute occlusions during the first month after coronary stenting. Therefore, a powerful association of platelet antiaggregant agents was tested. From December 1992 to October 1994, coronary stenting was successfully achieved in 1,294 patients (1,118 men, average age 60.5 +/- 10 years) who were then treated with the association of ticlopidine 0.25 g/day and aspirin 0.10 g/day for one month. This was covered with anticoagulation with a low molecular weight heparin for a variable period (one month, two weeks, then one week), according to the different phases of the study protocol. In all, 1487 stents were successfully implanted (1,330 Palmaz Schatz; 63 Cook; 80 Wictor; 13 AVE and 1 Strecker) in 1,326 vessels (520 left anterior descending, 208 left circumflex, 475 right coronary, 16 left main coronary arteries and 107 venous grafts) using balloon catheters of 2.5 mm to 5 mm diameter for average 3.45 +/- 0.4 mm). Major complications in the first month included 9 deaths (0.7%), 22 occlusions (1.7%): 14 myocardial infarcts (1%) and 11 aorto-coronary bypass procedures (0.85%). There were 136 local haematomas or false aneurysms (10.5%), 42 of which (3.25%) required blood transfusion or surgical repair. This multicenter trial of a protocol associating platelet antiaggregant agents and low molecular weight heparin for one month showed a low incidence of subocclusion after coronary stenting (1.7 +/= 2.5%) and should enable interventional cardiologists to widen the indications for coronary stenting.

[Evaluation, by flow cytometry, of activated platelet levels after coronarography and intraluminal angioplasty]. / Evaluation, par la cytométrie en flux, du taux de plaquettes activées après les coronarographies et les angioplasties intraluminales.

Coronarography and intraluminal angioplasty induce platelet activation. In this study, activated platelets were evaluated by measuring platelet-bound fibrinogen using a polyclonal fluorescent antibody in flow cytometry on whole blood. For normal subjects, the percentage of platelets binding fibrinogen was low (16.67%) and reached 81.0% in response to ADP. The percentages of platelets binding fibrinogen were evaluated 24 hours before and after coronarography. During intracoronary angioplasty, blood was collected from the catheter before and after the dilation and aspirin bolus (1 g). In both groups, the percentages of activated platelets were lower compared with those of the control group (respectively 3.96% and 5.59% versus 16.67%) following aggregation inhibitor, anticoagulant and calcium inhibitor therapies. Twenty-four hours after coronarography, platelet activation was noted (9.71% versus 3.96%). During angioplasty no significant activation was observed immediately after dilation (6.54% versus 5.59%). In both groups before the intervention, ADP stimulation was still responsible for platelet activation but to a lesser extent than in the control group (60.42% and 66.31% versus 81.0%). After coronarography, the platelet response to ADP was identical to that in the control group (81.01% versus 81.0%). Immediately after dilation, this activation was not observed in patients with an angioplasty. This study shows that platelet activation occurs 24 hours after coronarography, whereas after dilation and an aggregation inhibitor bolus this activation is not observed during angioplasty.

Recoil following Wiktor stent implantation for restenotic lesions of coronary arteries.

The purpose of this study was to determine acute recoil of the vessel wall immediately after Wiktor stent implantation in native coronary arteries of 77 consecutive patients and to assess whether there was compression or "late recoil" of the stent itself at long-term follow-up. Furthermore, the relationship between recoil and a number of clinical, angiographic, and procedural variables was studied in addition to the relation between acute recoil renarrowing or restenosis was assessed. All angiograms were analyzed with the Cardiovascular Angiography Analysis System using automated edge detection. Acute recoil was defined by the difference between the mean diameter of the fully expanded balloon on which the stent was mounted and the mean diameter of the stented segment. Late recoil was calculated by comparing the mean diameter of the stent itself immediately after implantation and at follow-up without opacification of the vessel. Acute recoil amounted to 0.25 +/- 0.32 mm or 8.2%. Multivariate analysis identified sex (coefficient = -0.20, p = 0.04) and stent/artery ratio (coefficient = 0.99, p = 0.0001) as the only independent predictors of acute recoil. "Late recoil" of the stent itself was not observed. The overall difference between the mean diameter of the stent itself immediately after implantation and at follow-up was -0.15 +/- 0.33 mm, suggesting an overall increase in diameter of 5.0%. There was no relation between acute recoil and late restenosis. On the contrary, there was a trend towards a greater degree of recoil in patients without restenosis. Moreover, linear regression analysis disclosed a weak but negative correlation between acute recoil and a loss in minimal luminal diameter (coefficient: -0.55, p = 0.04). The Wiktor stent effectively scaffolds the instrumented vessel. Only a minimal amount of acute recoil was noted, which did not contribute to late luminal renarrowing or restenosis. In addition, no late compression of the stent itself was observed. These data suggest that tissue ingrowth into the lumen of the stented segment is the main cause of late luminal renarrowing after stent implantation.

Angiographic predictors of recurrence of restenosis after Wiktor stent implantation in native coronary arteries.

Intracoronary stenting has been proposed as an adjunct to balloon angioplasty to improve the immediate and long-term results. However, late luminal narrowing has been reported following the implantation of a variety of stents. One of the studies conducted with the Wiktor stent is a prospective registry designed to evaluate the feasibility, safety and efficacy of elective stent implantation in patients with documented restenosis of a native coronary artery. To identify angiographic variables predicting recurrence of restenosis, the angiograms of the first 91 patients with successful stent implantation and without clinical evidence of (sub)acute thrombotic stent occlusion were analyzed with the Computer Assisted Angiographic Analysis System using automated edge detection. The incidence of restenosis was 44% by patient and 45% by stent according to the 0.72 mm criterion, and 30% by patient and 29% by stent according to the 50% diameter stenosis criterion. The risk for restenosis for several angiographic variables was determined using an univariate analysis and is expressed as odds ratio with corresponding confidence interval. The only statistically significant predictor of restenosis was the relative gain when it exceeded 0.48 using the 0.72 mm criterion (odds ratio 2.7, 95% confidence interval 1.1-6.4). Furthermore, the relation between the relative gain (increase in minimal luminal diameter normalized to vessel size) as angiographic index of vessel wall injury and relative loss (decrease in minimal luminal diameter normalized to vessel size) as index of neointimal thickening was analyzed using a linear regression analysis. When using the categorical approach to address restenosis, there is an increased risk for recurrent restenosis when the relative gain exceeds 0.48. The continuous approach underscores this concept by indicating a weak but positive relation between the relative gain and relative loss.

Wiktor stent implantation in patients with restenosis following balloon angioplasty of a native coronary artery.

Intracoronary stenting has been introduced as an adjunct to balloon angioplasty aimed at overcoming its limitations, namely acute vessel closure and late restenosis. This study reports the first experience with the Wiktor stent implanted in the first 50 consecutive patients. All patients had restenosis of a native coronary artery lesion after prior balloon angioplasty. The target coronary artery was the left anterior descending artery in 26 patients, the circumflex artery in 7 patients and the right coronary artery in 17 patients. The implantation success rate was 98% (49 of 50 patients). There were no procedural deaths. Acute or subacute thrombotic stent occlusion occurred in 5 patients (10%). All 5 patients sustained a nonfatal acute myocardial infarction. Four of these patients underwent recanalization by means of balloon angioplasty; the remaining patient was referred for bypass surgery. A major bleeding complication occurred in 11 patients (22%): groin bleeding necessitating blood transfusion in 6, gastrointestinal bleeding in 3 and hematuria in 2. Repeat angiography was performed at a mean of 5.6 +/- 1.1 months in all but 1 patient undergoing implantation. Restenosis, defined by a reduction of greater than or equal to 0.72 mm in the minimal luminal diameter or a change in diameter stenosis from less than to greater than or equal to 50%, occurred in 20 (45%) and 13 (29%) patients, respectively. In this first experience, the easiness and high technical success rate of Wiktor stent implantation are overshadowed by a high incidence of subacute stent occlusion and bleeding complications.(ABSTRACT TRUNCATED AT 250 WORDS)

Morphologic change in coronary artery stenosis with the Medtronic Wiktor stent: initial results from the core laboratory for quantitative angiography.

The purpose of this study was to assess the early changes in stenosis geometry after implantation of the Medtronic Wiktor stent in human coronary arteries. Morphologic changes were evaluated by quantitative coronary angiography using automated edge detection. The hemodynamic significance of the morphologic changes were assessed by the calculation of the theoretical pressure drop across the dilated and stented stenosis derived from the Poiseuile and turbulent resistances assuming a coronary blood flow of either 0.5, 1, or 3 ml/sec. Fifty patients were studied before and immediately after stent implantation. The stented coronary artery was the left anterior descending artery in 26 patients, the circumflex artery in eight patients, and the right coronary artery in 16 patients. Stent implantation resulted in an additional increase in the minimal luminal cross-sectional area and minimal luminal diameter of the dilated vessel without changing the curvature of the stenosis. Furthermore, there was a significant reduction of the "plaque area." This was associated with a normalization of the calculated resistances to flow and pressure drop across the stenosis. To a minimal extent, recoil (0.1 +/- 0.36 mm) was observed after stent implantation.

[Value of the combined Lastac laser-angioplasty technic in symptomatic superficial femoral occlusion]. / Intérêt de la technique combinée Lastac laser-angioplastie dans les occlusions fémorales superficielles symptomatiques.

The results of peripheral transluminal angioplasty are satisfactory in stenotic arteries but those observed in the recanalisation of occluded peripheral arteries are not so good. There would therefore seem to be a good therapeutic opportunity for laser between angioplasty and surgery for patients with symptomatic arterial occlusion. The authors report their experience with the Lastac laser in 12 patients with symptomatic superficial femoral arterial occlusion. This is a no-contact laser. All patients had surgical indications in case of failure to recanalise by laser, despite collateral circulation by the profunda artery which was inadequate on effort leading to claudication and a limited walking perimeter. After 1 initial failure, 11 successful procedures were performed. There were no perforations due to the Argon laser beam but 2 were observed with the guide wire which was rapidly sealed by the balloon catheter. A surgical haematoma at the percutaneous puncture point resulted in 1 reocclusion during the patient's hospital period so that the 11 technical successes became 10 clinical successes. At medium-term follow-up, one asymptomatic occlusion had occurred and one restenosis was successfully redilated. The advantages of a continuous Argon "Lastac" laser compared with a contact laser are its capacity for auto-control, its coaxial fibre placement and the absence of direct contact with the lesion. The coaxial fibre arrangement plays an important role in preventing vascular perforation. These factors enable it to be used with more safety in patients with arterial occlusion.

[Transluminal coronary angioplasty using a percutaneous axillary route with an arterial sheath]. / Angioplastie coronaire transluminale par voie percutanée axillaire avec introducteur artériel.

Out of 1400 percutaneous transluminal coronary angioplasties (PTCA), 23 (1.6 p. 100) were performed by the left percutaneous axillary approach because the bifemoral approach could not be used. There were 18 patients (17 men, 1 woman) with a mean age of 58 years. The coronary vessels dilated were the anterior interventricular artery (n = 4), the circumflex artery (n = 9) and the right coronary artery (n = 10), i.e. a total of 25 stenoses. The success rate in procedures was 83 p. 100 (19/23), and the primary success rate in patients was 83.3 p. 100 (15/18): Despite a good initial result, one patient developed inferior myocardial infarction as a result occlusion of a dominant distal circumflex artery, due to protamine administration immediately after the procedure. Another failure ascribable to the approach was due to selective catheterization being impossible. The mean duration of TCA was 38 min. In every cases the arterial introducer was withdrawn after neutralization with protamine. There were 4 cases of restenosis (25 p. 100) :3 were treated by a second PTCA using the percutaneous axillary approach and 1 by surgery. The method has the following disadvantages: (1) neutralization with protamine is mandatory (we had 1 case of occlusion with infarction after protamine in this series); (2) it is imperative to prevent the formation of a blood collection that would infiltrate the brachial plexus; for this purpose, the axillary cavity must be compressed effectively after PTCA and the puncture area must be watched for 24 to 48 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

[Electro-mechanical dissociation concomitant with myocardial reperfusion in the acute phase of myocardial infarction]. / Dissociation électro-mécanique contemporaine de la reperfusion myocardique en phase aiguë d'infarctus du myocarde.

An unusual case of transient electro-mechanical dissociation concomitant with myocardial reperfusion is reported. The patient had myocardial infarction caused by occlusion of the middle anterior interventricular artery relieved by injection of urokinase and plasminogen in situ. The dissociation could be documented by simultaneous ECG recording on 3 leads and direct intravascular recording of femoral arterial pressure, the patency of that artery, and its maintenance, being demonstrated by angiography. This clinical case can be added to the list of events which occur during reperfusion of the myocardium after prolonged ischaemia. Its mechanisms, so far, are purely conjectural.

[Intracavitary extraction of fragments of intracardiac catheters using a pigtail catheter. Apropos of 14 operations]. / Extraction endocavitaire de fragments de cathéters intracardiaques à l'aide d'une sonde "queue de cochon". A propos de 14 interventions.

Endocavitary extraction of intracardiac fragments of intravenous catheters was attempted in 14 patients over a 7 year period. The fragments were recovered in 13 cases under local anaesthesia without complications. The average duration of the procedure was less than 15 minutes. The technique requires a pigtail catheter, a material which is usually readily available in all catheter laboratories. This simple procedure may prevent complications and enable some patients to avoid surgery.

[Delayed filling of the anterior interventricular artery. Apropos of 9 cases]. / Retard de remplissage de l'artère interventriculaire antérieure. A propos de 9 cas.

Selective coronary angiography has shown that typical angina pectoris may occur in the absence of atheromatous coronary stenosis. Other causes of these attacks of pain have been found: coronary spasm, small vessel disease, abnormal dissociation of haemoglobin or metabolic disturbances of the myocardial cell. Of all the patients undergoing coronary angiography in 1984 at the Centre Cantini, 9 had no classical coronary lesions but delayed filling of the left anterior descending artery. This syndrome was described for the first time in 1972 by Tambe as the "slow flow velocity syndrome". The aim of this study was to analyse the clinical, ECG and haemodynamic profiles of those patients. Five of them also underwent stress Thallium myocardial scintigraphy. An ergometrine provocation test was performed afterwards under ECG control. Delayed filling was appreciated by comparison with the other vessels and also by measuring the filling time which was two or three times longer than in a control series of 9 patients with angina and normal coronary arteries. The difference was statistically significant. These findings were only observed in strictly normal coronary vessels; they were reproducible and unaffected by the administration of nitrate derivatives. In our series all 9 patients were men with an average age of 51.4 years. One patient was asymptomatic and had a history suggestive of myocardial infarction, and 4 others had typical angina of effort: all had abnormal exercise stress tests. The other 3 patients had spontaneous atypical chest pain, normal resting ECG and a negative exercise stress test (impossible in one case). The five stress Thallium scintigraphies showed myocardial perfusion defects.(ABSTRACT TRUNCATED AT 250 WORDS)

[Coronary revascularization at the acute phase of myocardial infarction. Short and median-term survival of 359 patients. Multicenter study]. / Désobstruction coronarienne à la phase aiguë de l'infarctus du myocarde. Survie à court et moyen terme de 359 patients. Etude multicentrique.

Three hundred and fifty nine consecutive patients from 4 different French centres who underwent attempted early coronary revascularisation during the acute phase of myocardial infarction by intracoronary thrombolysis (309 cases) intravenous thrombolysis (26 cases) and transluminal angioplasty (24 cases) were reviewed to evaluate the short and medium term results of these non-surgical techniques. Three groups of patients were identified from the results of initial and secondary coronary angiography: 1) deaths during the procedure (1.9%), 2) successes, with immediate and stable revascularisation (65%), 3) failures, also including initial successes with secondary reocclusion (33.1%). The global mortality at one month was 10.9%. This was significantly lower after revascularisation (p less than 0.001): 4.7% in patients with successful procedures and 17.6% in the others. The one year survival rate was also significantly higher in patients successful revascularisation (93 +/- 4% vs 75 +/- 8%, p less than 0.001). There were more recurrent infarctions and residual angina in patients with successful early coronary revascularisation: 7.7% and 12% respectively vs 4.2% and 8.4% respectively in the other patient group. In the successful group, 200 patients (86%) had one or more stenoses greater than 70% narrowing after coronary revascularisation. The recurrent infarction rate in the 94 patients treated medically was 9% and 17% had residual angina compared to 6% and 10% respectively in the 106 patients referred for coronary bypass surgery or undergoing complementary angioplasty. Three conclusions may be drawn from this non-randomised study of coronary revascularisation during the acute phase of myocardial infarction: attempts at coronary revascularisation do not aggravate the immediate prognosis of myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

[Treatment of recurrent ventricular tachycardias using oral propafenone]. / Traitement des tachycardies ventriculaires récidivantes par la propafénone orale.

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.

[Treatment of recurrent ventricular tachycardia with hydroquinidine. Evaluation of its efficacy with electrophysiological technics]. / Traitement des tachycardies ventriculaires récidivantes par l'hydroquinidine. Appréciation de l'efficacité par les techniques électrophysiologiques.

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.