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Dive into the research topics where Jean-Nicolas Dacher is active.

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Featured researches published by Jean-Nicolas Dacher.


Jacc-cardiovascular Interventions | 2012

Transfemoral Aortic Valve Replacement With the Edwards SAPIEN and Edwards SAPIEN XT Prosthesis Using Exclusively Local Anesthesia and Fluoroscopic Guidance: Feasibility and 30-Day Outcomes

Eric Durand; Bogdan Borz; Matthieu Godin; Christophe Tron; Pierre-Yves Litzler; Jean-Paul Bessou; Karim Bejar; Chiara Fraccaro; Carlos Sanchez-Giron; Jean-Nicolas Dacher; Fabrice Bauer; Alain Cribier; H. Eltchaninoff

OBJECTIVES The authors report the feasibility and 30-day outcomes of transfemoral aortic valve replacement (TAVR), using the Edwards SAPIEN (Edwards Lifesciences, Irvine, California) and Edwards SAPIEN XT (Edwards Lifesciences) prosthesis, implanted using exclusively local anesthesia and fluoroscopic guidance. BACKGROUND Transfemoral TAVR is often managed with general anesthesia. However, a simplified percutaneous approach using local anesthesia has become more popular because it offers multiple advantages in an elderly and fragile population. METHODS Between May 2006 and January 2011, the authors prospectively evaluated 151 consecutive patients (logistic EuroSCORE: 22.8 ± 11.8%) who underwent TAVR (SAPIEN: n = 78, SAPIEN XT: n = 73) using only local anesthesia and fluoroscopic guidance. The primary endpoint was a combination of all-cause mortality, major stroke, life-threatening bleeding, stage 3 acute kidney injury (AKI), periprocedural myocardial infarction (MI), major vascular complication, and repeat procedure for valve-related dysfunction at 30 days. RESULTS Transarterial femoral approach was surgical in all SAPIEN procedures and percutaneous in 97.3% of SAPIEN XT, using the ProStar vascular closure device, and was well tolerated in all cases. Conversion to general anesthesia was required in 3.3% (SAPIEN cases) and was related to complications. Vasopressors were required in 5.5%. Procedural success was 95.4%. The combined-safety endpoint was reached in 15.9%, including overall mortality (6.6%), major stroke (2.0%), life-threatening bleeding (7.9%), stage 3 AKI (0.7%), periprocedural MI (1.3%), major vascular complication (7.9%), and repeat procedure for valve-related dysfunction (2.0%) at 30 days. A permanent pacemaker was required in 5.3%. CONCLUSIONS This single-center, prospective registry demonstrated the feasibility and safety of a simplified transfemoral TAVR performed using only local anesthesia and fluoroscopic guidance in high surgical risk patients with severe aortic stenosis.


American Journal of Cardiology | 2013

Performance Analysis of EuroSCORE II Compared to the Original Logistic EuroSCORE and STS Scores for Predicting 30-Day Mortality After Transcatheter Aortic Valve Replacement

Eric Durand; Bogdan Borz; Matthieu Godin; Christophe Tron; Pierre-Yves Litzler; Jean-Paul Bessou; Jean-Nicolas Dacher; Fabrice Bauer; Alain Cribier; H. Eltchaninoff

The original European System for Cardiac Operative Risk Evaluation (EuroSCORE) has been recently updated as EuroSCORE II to optimize its efficacy in cardiac surgery, but its performance has been poorly evaluated for predicting 30-day mortality in patients who undergo transcatheter aortic valve replacement (TAVR). Consecutive patients (n = 250) treated with TAVR were included in this analysis. Transapical access was used in 60 patients, while 190 procedures were performed using a transfemoral approach. Calibration (risk-adjusted mortality ratio) and discrimination (C-statistic and U-statistic) were calculated for the logistic EuroSCORE, EuroSCORE II, and Society of Thoracic Surgeons (STS) scores for predicting 30-day mortality. Observed mortality was 7.6% in the overall population (6.3% and 11.7% for the transfemoral and transapical cohorts, respectively). Predicted mortality was 22.6 ± 12.8% by logistic EuroSCORE, 7.7 ± 5.8% by EuroSCORE II, and 7.3 ± 4.1% by STS score. The risk-adjusted mortality ratio was 0.34 (95% confidence interval [CI] 0.10 to 0.58) for logistic EuroSCORE, 0.99 (95% CI 0.29 to 1.69) for EuroSCORE II, and 1.05 (95% CI 0.30 to 1.79) for STS score. Moderate discrimination was observed with EuroSCORE II (C-index 0.66, 95% CI 0.52 to 0.79, p = 0.02) compared to the logistic EuroSCORE (C-index 0.63, 95% CI 0.51 to 0.76, p = 0.06) and STS (C-index 0.58, 95% CI 0.43 to 0.73, p = 0.23) score, without a significant difference among the 3 risk scores. Discrimination was slightly better in the transfemoral cohort compared to the transapical cohort with the 3 risk scores. In conclusion, EuroSCORE II and the STS score are better calibrated than the logistic EuroSCORE but have moderate discrimination for predicting 30-day mortality after TAVR.


American Journal of Cardiology | 2011

Evaluation of Multislice Computed Tomography Early After Transcatheter Aortic Valve Implantation With the Edwards SAPIEN Bioprosthesis

J. Caudron; Jeannette Fares; Camille Hauville; Alain Cribier; Jean-Nicolas Dacher; Christophe Tron; Fabrice Bauer; Pierre-Yves Litzler; Jean-Paul Bessou; H. Eltchaninoff

Currently, imaging assessment of patients who undergo transcatheter aortic valve implantation is based mainly on echocardiography and angiography, both limited to provide a 3-dimensional evaluation of the prosthesis within the native valve. This study involved 34 patients who underwent multislice computed tomography (MSCT) after transcatheter aortic valve implantation. Prosthesis expansion and circularity, depth of implantation, apposition degree at the ventriculoaortic junction, and positioning in relation to coronary artery ostia were evaluated. Early clinical events such as aortic regurgitation and periprocedural conduction abnormalities were recorded and correlated with multislice computed tomographic findings. MSCT provided comprehensive 3-dimensional assessments of the prostheses in 31 of 34 of patients (91%). Expansion was excellent (mean expansion ratio 100.0 ± 10.4%) and increased significantly from the ventricular side to the aortic side of the prosthesis. Circular deployment was achieved in most patients and increased from the ventricular to the aortic side. Mean implantation depth was -2.4 ± 2.5 mm, associated with a low rate (12%) of permanent pacemaker implantation. Patients with a new conduction abnormalities had the deepest prosthesis implantation, associated with lesser expansion and circularity. Perfect apposition on MSCT was associated with a low rate of significant aortic regurgitation. In conclusion, MSCT is able to provide an accurate 3-dimensional evaluation of prosthesis deployment and positioning after transcatheter aortic valve implantation. Moreover, these anatomic findings correlate with the most frequent early complications (i.e., the occurrence of aortic regurgitation and conduction abnormalities).


Journal of Cardiovascular Computed Tomography | 2014

Effect of the ellipsoid shape of the left ventricular outflow tract on the echocardiographic assessment of aortic valve area in aortic stenosis

Clément De Vecchi; J. Caudron; B. Dubourg; Nathalie Pirot; Valentin Lefebvre; Fabrice Bauer; H. Eltchaninoff; Jean-Nicolas Dacher

BACKGROUND Previous studies showed discrepancies between echocardiographic and multidector row CT (MDCT) measurements of aortic valve area (AVA). OBJECTIVE Our aim was to evaluate the effect of the ellipsoid shape of the left ventricular outflow tract (LVOT), as shown and measured by MDCT, on the assessment of AVA by transthoracic echocardiography (TTE) in patients with severe aortic stenosis. METHODS This retrospective single-center study involved 49 patients with severe aortic stenosis referred before transcatheter aortic valve implantation. The AVA was deduced from the continuity equation on TTE and from planimetry on cardiac MDCT. Area of the LVOT was calculated as follows: on TTE, from the measurement of LVOT diameter on parasternal long-axis view; on MDCT, from manual planimetry by using multiplanar reconstruction perpendicular to LVOT. RESULTS At baseline, correlation of TTE vs MDCT AVA measurements was moderate (R = 0.622; P < .001). TTE underestimated AVA compared with MDCT (0.66 ± 0.15 cm2 vs. 0.87 ± 0.15 cm2; P < .001). After correcting the continuity equation with the LVOT area as measured by MDCT, mean AVA drawn from TTE did not differ from MDCT (0.86 ± 0.2 cm2) and correlation between TTE and MDCT measurements increased (R = 0.704; P < .001). CONCLUSION Assuming that LVOT area is circular with TTE results in constant underestimation of the AVA with the continuity equation compared with MDCT planimetry. The elliptical not circular shape of LVOT largely explains these discrepancies.


Diagnostic and interventional imaging | 2016

CT and MR imaging in congenital cardiac malformations: Where do we come from and where are we going?

Jean-Nicolas Dacher; E. Barre; I. Durand; T. Hazelzet; M. Brasseur-Daudruy; É. Blondiaux; F. Bauer; B. Dubourg

The management of patients with congenital heart disease was profoundly changed firstly by the advent of pediatric and prenatal ultrasound and then more recently by cardiac magnetic resonance imaging (MRI) and computed tomography (CT) of the heart and great vessels. The improved life expectancy of these patients has brought about new medical and imaging requirements. MRI and CT are increasing second line techniques in this group of patients. This article summarizes the advantages and limitations of CT and MRI in some frequently encountered situations in children and adults followed up for congenital heart disease.


Diagnostic and interventional imaging | 2014

Incidental diagnosis of a familial left ventricular noncompaction on a chest CT angiography

B. Dubourg; B. D’Heré; C. de Vecchi; J. Caudron; A. Savoure; D. Stepowski; V. Lefebvre; Fabrice Bauer; H. Eltchaninoff; Jean-Nicolas Dacher

Left ventricular noncompaction (LVNC) is a rare genetic cardiomyopathy, which may progress to left ventricular (LV) dilatation and systolic dysfunction and often leads to cardioverter-defibrillator implantation and/or cardiac transplantation. Family investigation is essential. The diagnosis is based on three imaging examinations or autopsy. We report an incidental diagnosis of a familial form of LVNC, discovered on a chest computed tomography (CT) angiography performed in the index patient at the emergency department to rule out pulmonary embolism.


Diagnostic and interventional imaging | 2016

Abnormal origin and interarterial course of coronary arteries in Marfan syndrome: CT coronary angiography features.

I. Vasies; B. Dubourg; M. Lempicki; F. Doguet; Jean-Nicolas Dacher

Marfan syndrome (MS) is an inherited connective tissue disorder that is responsible for a variety of abnormalities of the cardiovascular system. The prevalence of abnormal aortic origin of coronary arteries in the general population ranges between 0.6 and 1.3% on angiography studies [1] and reaches 1.96% on computed tomography coronary angiography (CTCA) [2—4]. Interarterial course is rare, but represents a risk factor of sudden death, especially on exercise or after exercise. The association between MS and abnormal aortic origin of coronary arteries was scarcely reported in the literature [5]. We describe the imaging presentation of abnormal origin and interarterial course of coronary arteries in a patient with MS on CTCA and emphasize the role of this technique for the depiction of this abnormality.


Diagnostic and interventional imaging | 2013

Is it possible to do without the study of myocardial perfusion in 2013

Jean-Nicolas Dacher; V. Lefebvre; B. Dubourg; J.-F. Deux; J. Caudron

The analysis of myocardial perfusion is a key step in the cardiac MRI examination. In routine work, this exploration carried out at rest is based on the qualitative first pass study of gadolinium with an ECG-triggered saturation recovery bFFE sequence. In view of recent knowledge, the analysis of the myocardial perfusion under vasodilator stress may be carried out by scintigraphy or MRI, the latter benefiting from the absence of exposure to ionizing rays and a lower cost. Besides coronary disease, the perfusion sequence provides a rich semiology to compare with the clinics and the data from other sequences. Arterial Spin Labeling (ASL) is an alternative technique used in the animal to quantify myocardial perfusion.


International Journal of Cardiology | 2017

Head-to-head comparison of the diagnostic performance of coronary computed tomography angiography and dobutamine-stress echocardiography in the evaluation of acute chest pain with normal ECG findings and negative troponin tests: A prospective multicenter study ☆

Eric Durand; Fabrice Bauer; Nicolas Mansencal; Arshid Azarine; Benoit Diebold; Albert Hagège; Ludivine Perdrix; Martine Gilard; Yannick Jobic; H. Eltchaninoff; Mourad Bensalah; B. Dubourg; J. Caudron; Ralph Niarra; Gilles Chatellier; Jean-Nicolas Dacher; Elie Mousseaux

OBJECTIVE To perform a head-to-head comparison of coronary CT angiography (CCTA) and dobutamine-stress echocardiography (DSE) in patients presenting recent chest pain when troponin and ECG are negative. METHODS Two hundred seventeen patients with recent chest pain, normal ECG findings, and negative troponin were prospectively included in this multicenter study and were scheduled for CCTA and DSE. Invasive coronary angiography (ICA), was performed in patients when either DSE or CCTA was considered positive or when both were non-contributive or in case of recurrent chest pain during 6month follow-up. The presence of coronary artery stenosis was defined as a luminal obstruction >50% diameter in any coronary segment at ICA. RESULTS ICA was performed in 75 (34.6%) patients. Coronary artery stenosis was identified in 37 (17%) patients. For CCTA, the sensitivity was 96.9% (95% CI 83.4-99.9), specificity 48.3% (29.4-67.5), positive likelihood ratio 2.06 (95% CI 1.36-3.11), and negative likelihood ratio 0.07 (95% CI 0.01-0.52). The sensitivity of DSE was 51.6% (95% CI 33.1-69.9), specificity 46.7% (28.3-65.7), positive likelihood ratio 1.03 (95% CI 0.62-1.72), and negative likelihood ratio 1.10 (95% CI 0.63-1.93). The CCTA: DSE ratio of true-positive and false-positive rates was 1.70 (95% CI 1.65-1.75) and 1.00 (95% CI 0.91-1.09), respectively, when non-contributive CCTA and DSE were both considered positive. Only one missed acute coronary syndrome was observed at six months. CONCLUSIONS CCTA has higher diagnostic performance than DSE in the evaluation of patients with recent chest pain, normal ECG findings, and negative troponine to exclude coronary artery disease.


American Journal of Cardiology | 2016

A Prospective Analysis of Early Discharge After Transfemoral Transcatheter Aortic Valve Implantation.

Anna Serletis-Bizios; Eric Durand; Guillaume Cellier; Christophe Tron; Fabrice Bauer; Bastien Glinel; Jean-Nicolas Dacher; Alain Cribier; H. Eltchaninoff

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Nicolas Bettinger

Columbia University Medical Center

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Albert Hagège

Paris Descartes University

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Arshid Azarine

Paris Descartes University

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