P Guyon

Centre Chirurgical Marie Lannelongue, Plessis-Robinson, Île-de-France, France

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Publications (19)118.57 Total impact

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    Circulation 08/2012; 126(9):e124-7. · 15.20 Impact Factor
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    ABSTRACT: The percutaneous aortic valve replacement (TAVI) is the most recent and promising procedure in the area of interventional cardiology with a rapidly growing number of interventions worldwide. The transfemoral approach being less invasive, it has become the predominant access for the device delivery. The prevention of vascular complications by an optimal risk stratification using appropriate imaging techniques (vascular CT scan and angiography), optimised techniques for femoral puncture (active control of the arterial punction, crossover…) and skilled teams for peripheral angioplasty and percutaneous arterial closure devices (Prostar) has become mandatory given the fragile target population for TAVI. Vascular complications remain indeed one of the most frequent complication although the trend toward reduced sheeths size led to significant reduction This is mandatory regarding the needed size of the vascular arterial access – itself with constant improvement by minimising the initial 24 French with mandatory real chirurgical closure to the actual 18-19 French and soon 16 French. The improvement of the implanted devices is due to the recent evidence of the promising future of this technique and the important technological effort realised by the industry not only on the implanted aortic protesis but also on their delivering catheters.
    Annales de cardiologie et d'angeiologie 08/2012; 61(4):281–286. · 0.21 Impact Factor
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    ABSTRACT: Transcatheter aortic-valve implantation (TAVI) is an emerging intervention for the treatment of high-risk patients with severe aortic stenosis and coexisting illnesses. We report the results of a prospective multicenter study of the French national transcatheter aortic-valve implantation registry, FRANCE 2. All TAVIs performed in France, as listed in the FRANCE 2 registry, were prospectively included in the study. The primary end point was death from any cause. A total of 3195 patients were enrolled between January 2010 and October 2011 at 34 centers. The mean (±SD) age was 82.7±7.2 years; 49% of the patients were women. All patients were highly symptomatic and were at high surgical risk for aortic-valve replacement. Edwards SAPIEN and Medtronic CoreValve devices were implanted in 66.9% and 33.1% of patients, respectively. Approaches were either transarterial (transfemoral, 74.6%; subclavian, 5.8%; and other, 1.8%) or transapical (17.8%). The procedural success rate was 96.9%. Rates of death at 30 days and 1 year were 9.7% and 24.0%, respectively. At 1 year, the incidence of stroke was 4.1%, and the incidence of periprosthetic aortic regurgitation was 64.5%. In a multivariate model, a higher logistic risk score on the European System for Cardiac Operative Risk Evaluation (EuroSCORE), New York Heart Association functional class III or IV symptoms, the use of a transapical TAVI approach, and a higher amount of periprosthetic regurgitation were significantly associated with reduced survival. This prospective registry study reflected real-life TAVI experience in high-risk elderly patients with aortic stenosis, in whom TAVI appeared to be a reasonable option. (Funded by Edwards Lifesciences and Medtronic.).
    New England Journal of Medicine 05/2012; 366(18):1705-15. · 54.42 Impact Factor
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    ABSTRACT: The value of prehospital initiation of glycoprotein IIb/IIIa inhibitors remains a controversial issue. We sought to investigate whether in-ambulance initiation of abciximab in patients with ST-segment elevation myocardial infarction (STEMI) improves ST-segment elevation resolution (STR) after primary percutaneous coronary intervention (PCI). MISTRAL (Myocardial Infarction with ST-elevation Treated by Primary Percutaneous Intervention Facilitated by Early Reopro Administration in Alsace) is a prospective, randomized, double-blind study. Two hundred and fifty-six patients with acute STEMI were allocated to receive abciximab either in the ambulance (ambulance group, n=127) or in the catheterization laboratory (hospital group, n=129). The primary end point was complete (>70%) STR after PCI. Complete STR was not significantly different between the 2 groups (before PCI, 21.6% versus 15.5%, P=0.28; after PCI, 70.3% versus 65.8%, P=0.49). Thrombolysis In Myocardial Infarction (TIMI) 2 to 3 flow rates before PCI tended to be higher in the ambulance group (46.8% versus 35%, P=0.08) but not after PCI (70.3% versus 65.8%, P=0.49). Slow flow tended to be lower (5.6% versus 13.4%, P=0.07), and distal embolization occurred significantly less often in the ambulance group (8.1% versus 21.1%, P=0.008). One- and 6-month major adverse cardiac event rates were low and similar in both groups. Early ambulance administration of abciximab in STEMI did not improve either STR or TIMI flow rate after PCI. However, it tended to improve TIMI flow pre-PCI and decreased distal embolization during procedure. Larger studies are needed to confirm these results.
    Circulation Cardiovascular Interventions 02/2012; 5(1):69-76, S1. · 6.54 Impact Factor
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    ABSTRACT: The percutaneous aortic valve replacement (TAVI) is the most recent and promising procedure in the area of interventional cardiology with a rapidly growing number of interventions worldwide. The transfemoral approach being less invasive, it has become the predominant access for the device delivery. The prevention of vascular complications by an optimal risk stratification using appropriate imaging techniques (vascular CT scan and angiography), optimised techniques for femoral puncture (active control of the arterial punction, crossover…) and skilled teams for peripheral angioplasty and percutaneous arterial closure devices (Prostar) has become mandatory given the fragile target population for TAVI. Vascular complications remain indeed one of the most frequent complication although the trend toward reduced sheeths size led to significant reduction This is mandatory regarding the needed size of the vascular arterial access - itself with constant improvement by minimising the initial 24 French with mandatory real chirurgical closure to the actual 18-19 French and soon 16 French. The improvement of the implanted devices is due to the recent evidence of the promising future of this technique and the important technological effort realised by the industry not only on the implanted aortic protesis but also on their delivering catheters.
    Annales de cardiologie et d'angeiologie 12/2011; 61(4):281-6. · 0.21 Impact Factor
  • Archives of Cardiovascular Diseases Supplements 01/2011; 3(1):79-79.
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    ABSTRACT: Aims: To evaluate the safety and long-term efficacy of a true dedicated bifurcation bare metal stent (DBS) for the treatment of bifurcation coronary artery lesions. Methods and results: Thirty-four patients were enrolled in this prospective multicentre study. The majority of culprit lesions were located on the left anterior descending artery/diagonal bifurcation (n=19) followed by the distal protected left main (n=7), the left circumflex artery/obtuse marginal (n=4) and the distal right coronary artery/posterior descending artery (n=4). Successful delivery of the DBS stent at the bifurcation site was achieved in 32 patients (94%). Angiographic follow-up at six months was complete in 29 patients (91%). Clinical follow-up was achieved at five years in all DBS patients. There were no cardiac deaths or stent thrombosis. At six months, the MACE rate was 6/32 (19%) and the total binary restenosis rate was 10/29 (34%). MACE at 5 years consisted only in target vessel revascularisation and occurred in eight patients (25%). Conclusions: The DBS bare metal true bifurcated stent can be delivered successfully and safely in selected bifurcated lesions and has demonstrated long-term efficacy in most patients.
    EuroIntervention: journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology 04/2008; 3(5):558-65. · 3.17 Impact Factor
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    ABSTRACT: Treatment of bifurcation lesions remains a technical challenge. Among 13 stents previously tested in a bench study, the Bestent seemed of particular interest in this indication as it provided good access to the side branch after stent implantation in the main branch associated with a satisfactory coverage of the lesion after kissing balloon inflation. The use of Bestent implanted in the main branch or both branches for treatment of bifurcation lesions involving a side branch > or = 2.2 mm in diameter was prospectively evaluated in a dual-center prospective study with a prospective 6-month clinical follow-up. All angiographic documents were analyzed by an independent corelab (CORISIS). Between 11 September 1997 and 21 February 1998, 96 patients were consecutively included (mean age, 63.7 +/- 11.4 years; 81.3% male; 58.3% with unstable angina and 6.3% acute myocardial infarction). The lesion involved the left anterior descending-diagonal coronary bifurcation in 55% of cases, left circumflex-marginal 23%, posterior descending-postero-lateral 12%, distal left main 6%, and others 4%. The main branch (proximal reference diameter: 3.43 +/- 0.45 mm) was stented in 98% of cases and the side branch (2.72 +/- 0.38 mm) in 38% (both branches in 34% of cases). T-stenting or provisional T-stenting was used in 88% of cases and final kissing balloon inflation was performed in 78% of cases. Procedural success was obtained in 100% of cases in the main branch and 98% in both branches. Major cardiac and cerebral events (MACCE) during hospitalization occurred in 4.2% of cases, non-Q-wave myocardial infarction (MI) in 3.1%, Q-wave MI in 1.0%, repeat PTCA in 2.1%; there were no major access site complication, no emergency coronary artery bypass grafting operation, no death. At 6-month follow-up, total MACCE rate was 14.6% (Q-wave MI, 3.1%; non-Q-wave MI, 3.1%; target vessel revascularization, 9.4%; death, 2.1%). Patients with target vessel revascularization (TVR) had restenosis of both branches in 22.2% of cases, main branch in 22.2%, and side branch in 55.6%. This study shows that using a simple strategy of provisional T-stenting of the side branch in the majority of cases, the Bestent can be used for treating bifurcation lesions with a high rate of success and an acceptable rate of TVR at 6-month follow-up.
    Catheterization and Cardiovascular Interventions 05/2002; 55(4):427-33. · 2.51 Impact Factor
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    ABSTRACT: Stenting has been demonstrated to be superior to balloon angioplasty in de novo focal lesions located in large native vessels. However, in small vessels, the benefit of stenting remains questionable. A total of 381 symptomatic patients with de novo focal lesion located on a small coronary segment vessel (<3 mm) were randomly assigned to either stent implantation (192 patients; 197 lesions) or standard balloon angioplasty (189 patients; 198 lesions). The primary end point was the angiographic restenosis rate at 6 months, as determined by quantitative coronary angiography. On intention-to-treat analysis, angiographic success rate and major adverse cardiac events were comparable: 97.9% and 4.6% versus 93.9% and 5.8% in the stent group and the balloon group, respectively. After the procedure, a larger acute gain was achieved with stent placement (1.35+/-0.45 versus 0.94+/-0.47 mm, P=0.0001), resulting in a larger minimal lumen diameter (2.06+/-0.42 versus 1.70+/-0.46 mm, P=0.0001). At follow-up (obtained in 91% of patients), angiographic restenosis rate was 21% in the stent group versus 47% in the balloon group (P=0.0001), a risk reduction of 55%. Repeat target lesion revascularization was less frequent in the stent group (13% versus 25%, P=0.0006). Elective stent placement in small coronary arteries with focal de novo lesions is safe and associated with a marked reduction in restenosis rate and subsequent target lesion revascularization rate at 6 months.
    Circulation 10/2001; 104(14):1604-8. · 15.20 Impact Factor
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    ABSTRACT: Percutaneous transluminal coronary angioplasty (PTCA) is an alternative to fibrinolysis in the treatment of acute myocardial infarction (AMI). However, after balloon PTCA, the rate of early re-occlusion, of re-infarctus and of restenosis remains high. Stent implantation with antiplatelet drug regimen (aspirin, ticlid) limits these risks. Abciximab (new GPIIb/IIIa receptors inhibitor) reduces PTCA complications rate in the acute coronary syndromes. Intravenous administration of abciximab can restore a normal flow in the infarcted related coronary artery (IRA) after few minutes. A monocentric, non randomized, prospective pilot study was iniated to assess the feasibility of pre-hospital treatment with abciximab in preparation to primary PTCA stenting in AMI (primary endpoint) and to appreciate potential benefits in initial IRA patency as well as prevention of PTCA thrombotic complications (secondary endpoint). Between April 1997 and January 1998, 38 AMI were treated with abciximab in pre-hospital phase (group A). Mobil Intensive Care Unit (MICU) team implemented the treatment and guaranteed immediate transport to the cathlab (abciximab bolus-coronary angiography time = 37 +/- 17 min). Immediate results were compared to those of 198 paired patients who were treated for AMI during the same period (Group T). Initial IRA flow TIMI grade 3 was significantly higher in group A, 24%, than in group T, 9% (p < 0.017). The rates of per-procedural complications (no flow, distal embolism), of local complications, of transfusions were not significantly different. During 1 month follow-up, there was no significant difference between group A and group T concerning death, re-MI, stent thrombosis and new revascularization. To conclude, the pre-hospital treatment with abciximab in AMI is feasible by MICU medical team without any delay of the cathlab admission. It is associated with no increased hemorrhagic complications rate. The abciximab pre-hospital treatment improves the initial IRA patency. These encouraging preliminary results expect to be confirmed by larger, multicentric, randomized and prospective studies.
    Archives des maladies du coeur et des vaisseaux 10/1999; 92(10):1301-8. · 0.40 Impact Factor
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    ABSTRACT: Coronary angioplasty of bifurcation lesions remains a technical challenge. Balloon angioplasty induces recoil and the "snow-plow" effect with a risk of side branch occlusion. The late result is associated with a high rate of reintervention. Randomized studies in nonbifurcated lesions have demonstrated better short- and midterm results after stent placement. We propose the "culotte" technique as a new technique to place intracoronary stents in bifurcation lesions: implantation of 2 similar stents in 2 steps in the main branch and in the side branch with overlapping of the 2 stents in the main branch before bifurcation. We performed this technique in 50 patients (in the left anterior diagonal branch in 33, in the left circumflex obtuse marginal branch in 12, in the right coronary artery in 4, and in the left main coronary artery in 1). The clinical success rate was 94% with 3 non-Q-wave myocardial infarctions. Late results indicated a 24% target lesion revascularization rate, which improved when a true kissing balloon inflation was used to achieve final deployment of both stents. This culotte technique is highly feasible and provides excellent short-term results. Assessment of its midterm benefit requires further study.
    The American Journal of Cardiology 11/1998; 82(8):943-9. · 3.21 Impact Factor
  • Journal of The American College of Cardiology - J AMER COLL CARDIOL. 01/1998; 31:312-313.
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    ABSTRACT: RATIONALE FOR ANTITHROMBOSIS THERAPY: Introducing a foreign body into the coronaries raises the risk of thrombosis in the acute phase and for the 4 following weeks. The objective of antithrombotic therapy is to inhibit platelet adhesion and aggregation or to induce hypocoagulability. AT IMPLANTATION: High-dose heparin is given in a bolus following pretreatment with aspirin. ASPIRIN-TICLOPIDINE COMBINATION: The risk of subacute thrombosis is low, about 1%, and the rate of vascular complications is minimal. Treatment is simple and compatible with short hospitalization.
    La Presse Médicale 05/1997; 26(11):532-5. · 0.87 Impact Factor
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    ABSTRACT: GENERAL CHARACTERISTICS: Several criteria are used for coronary stent design: biocompatibility, i.e. the capacity to resist thrombotic events and corrosion, flexibility, radial force sufficient to resist elastic recoil, percentage of the lesion covered, radio-opacity, minimal shortening at opening, absence of effect on collateral branches, possibility to use small calibre probe guides, and cost. TWO CATEGORIES: Both tubular stents (self-expanding stents and balloon stents) and filamentary stents (made of stainless steel or tantalum) are used, THE IDEAL STENT: There is no one ideal stent. Choice is dictated by the characteristics of the lesion and by the status of the artery to treat.
    La Presse Médicale 05/1997; 26(11):536-40. · 0.87 Impact Factor
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    ABSTRACT: BETTER THAN ANGIOPLASTY: Prolonging inflation with a perfusion balloon decreases the risk of acute coronary occlusion after angioplasty. The longer the artery remains patent, the greater the chances of 0% residual stenosis. This is what the sent allows. Stent act on both mechanisms of stenosis: elastic recoil and fibrous remodeling of the arterial plaque. TARGETTED ACTION: Stents improve angioplasty prevention of acute stenosis. They have a real action on preventing degeneration of the saphenous graft and lead to a significant reduction in the rate of restenosis of the dilated site. There are however two specific complications: subacute occlusion and greater incidence of vascular events. Stents are particularly indicated for the treatment of restenosis and chronic occlusions. TWO IMPROVEMENTS: Risks related to the implantation of a foreign body in the vascular system have been reduced with the use of ticlopidine and high-pressure stent implantation. POSITIVE RESULTS: Stents have produced better angiographic results. They limit restenosis and the number of revascularizations required in treated patients. Several questions concerning indications remain open.
    La Presse Médicale 05/1997; 26(11):526-31. · 0.87 Impact Factor
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    ABSTRACT: The authors report the case of a patient undergoing coronary angiography for angina who had an anomalous origin of the septal perforator artery from a separate ostium. Anomalies of the coronary arteries may consist not only of anomalous trajectories and coronary fistulae but also of anomalous origins of the main coronary arteries. The anomalous origin of a septal artery from a separate ostium is very rare accounting for 0.5% of cases in the medical literature. In some cases, this artery provides a collateral circulation for occluded main coronary vessels, thereby preserving left ventricular contractility.
    Archives des maladies du coeur et des vaisseaux 04/1996; 89(3):371-3. · 0.40 Impact Factor
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    ABSTRACT: The straightening of a sinuous proximal segment of a coronary artery using the stiffness of the guidewire has recently been recognized as likely to cause false coronary lesions. The accurate diagnosis between a true dissection and a pseudo-lesion is usually only done once all intra-coronary material has been removed into the guiding catheter. Such a manoeuvre may prove dangerous in case of dissection. We propose to demonstrate that it is possible to diagnose this phenomenon while leaving the guidewire within the coronary artery, and withdrawing it progressively until its floppy segment rests equally on either side of the suspect lesion.
    Catheterization and Cardiovascular Diagnosis 02/1994; 31(1):37-40.
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    Journal of the American College of Cardiology 31:17. · 14.09 Impact Factor
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    ABSTRACT: Percutaneous transluminal balloon aortic valvuloplasty was introduced in 1985 and, owing to its sometimes dramatic short-term results, it has rapidly become a useful procedure in the management of aortic stenosis in elderly subjects. The purpose of this study was to determine its clinical results at medium-term and to identify possible prognostic factors in order to improve the selection of patients suitable for this technique. Between January 1986 and December 1987, 78 patients (30 men, 48 women, aged from 60 to 93 years, mean 80 +/- 6.7 years) totalling 85 procedures were selected among 102 dilatations on the basis of a primary success without complications. Dilatation was performed by a technique similar to that described by Cribier et al. The follow-up period was 10 +/- 5.7 months (range: 1 to 27 months). The aortic valve area increased from 0.47 +/- 0.15 cm2 to 0.77 +/- 0.23 cm2, i.e. from 0.29 +/- 0.09 cm2/m2 to 0.48 +/- 0.13 cm2/m2 as regards the indexed area. The hospital mortality rate was 3.3 p. 100. At the end of the follow-up period 55 p. 100 of the patients were in NYHA class I or II; 29 p. 100 had died, 10 p. 100 had undergone a second dilatation and 13 p. 100 had had aortic valve replacement. This distribution into functional classes and major cardiac events was not significantly different in the subgroup of patients with an aortic valve area greater than 0.9 cm2 or in the subgroup of primary failure. The patients who died for cardiac reasons were older (p less than 0.01), had a lower cardiac output before and after dilatation (p less than 0.001) and a lower ejection fraction after dilatation (p less than 0.05) or even before in case of early death (p less than 0.05). Mortality and morbidity therefore were high at medium-term and unrelated to the haemodynamic effect of dilatation. On the other hand, the left ventricular systolic function was determinant, mainly because it could improve or remain stable when initially altered. These results suggest that only patients for whom aortic valve replacement is truly contra-indicated and who have a limited alteration of left ventricular function should be selected for aortic valvuloplasty.
    Archives des maladies du coeur et des vaisseaux 82(8):1397-404. · 0.40 Impact Factor