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Le Ven, Florent

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Le Ven
Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval
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  • Publication
    Accès libre
    Mitral regurgitation in low-flow, low-gradient aortic stenosis patients undergoing TAVR : insights from the TOPAS-TAVI registry
    (Elsevier, 2020-02-12) Freitas Ferraz, Afonso; Dahou, Abdellaziz; Lerakis, Stamatios A.; Nombela-Franco, Luis; Rodés-Cabau, Josep; Gilard, Martine; Le Ven, Florent; Cavalcante, João L.; Amat Santos, Ignacio J.; Makkar, Rajendra; Annabi, Mohamed Salah; Herrmann, Howard C.; Pelletier Beaumont, Émilie; Windecker, Stephan; Pibarot, Philippe; Enriquez-Sarano, Maurice; Clavel, Marie-Annick; Cheema, Asim; Ribeiro, Henrique B.; Muñoz, Antonio; García del Blanco, Bruno; Zajarias, Alan; Lisko, John C.; Hayek, Salim; Babaliaros, Vasilis; Gleason, Thomas G.; Chakravarty, Tarun; Szeto, Wilson Y.; Agustin, Alberto de; Serra, Vicenç; Schindler, John Thomas
    Objectives : This study sought to determine the incidence, clinical impact, and changes over time of mitral regurgitation (MR) in patients with low-flow, low-gradient aortic stenosis (LFLG-AS) undergoing transcatheter aortic valve replacement (TAVR). Background : Few data exist on the clinical impact and changes in severity over time of MR in patients with LFLG-AS undergoing TAVR. Methods : A total of 308 TAVR candidates with LFLG-AS were included. Patients were categorized according to MR severity at baseline, and presence of MR improvement at 12-month follow-up. Clinical outcomes were assessed at 1 and 12 months (+ echocardiography), and yearly thereafter. Results : Baseline mild and moderate-to-severe MR were present in 118 (38.3%) and 115 (37.3%) patients, respectively. MR was of functional and mixed etiology in 77.2% and 22.7% of patients, respectively. A total of 131 patients (42.5%) died after a median follow-up of 2 (1 to 3) years. Baseline moderate-or-greater MR had no impact on mortality (hazard ratio [HR]: 1.34; 95% confidence interval [CI]: 0.72 to 2.48) or heart failure hospitalization (HR: 1.02; 95% CI: 0.49 to 2.10). At 1-year follow-up, MR improved in 44.3% of patients and remained unchanged/worsened in 55.7%. The lack of MR improvement was associated with a higher risk of all-cause and cardiac mortality (HR: 2.02; 95% CI: 1.29 to 3.17; HR: 3.03; 95% CI: 1.27 to 7.23, respectively), rehospitalization for cardiac causes (HR: 1.50; 95% CI: 1.04 to 2.15), and an increased overall-mortality/heart failure rehospitalization (HR: 1.94; 95% CI: 1.25 to 3.02). A higher baseline left ventricular end-diastolic diameter and a higher increase in left ventricular ejection fraction were found to be independent predictors of MR improvement at 1-year follow-up (odds ratio: 0.69; 95% CI: 0.51 to 0.94; and odds ratio: 0.81; 95% CI: 0.67 to 0.96, respectively). Conclusions : Most TAVR candidates with LFLG-AS had some degree of MR, of functional origin in most cases. MR improved in about one-half of patients, with larger left ventricular size and a higher increase in left ventricular ejection fraction post-TAVR determining MR improvement over time. The lack of MR improvement at 1 year was associated with poorer outcomes.
  • Publication
    B-Type natriuretic peptide and high-sensitivity cardiac troponin for risk stratification in low-flow, low-gradient aortic stenosis a substudy of the TOPAS study
    (American College of Cardiology Foundation, 2017-10-05) Dahou, Abdellaziz; O'Connor, Kim; Rodés-Cabau, Josep; Le Ven, Florent; Côté, Nancy; Capoulade, Romain; Pibarot, Philippe; Dumesnil, Jean G.; Clavel, Marie-Annick; Ribeiro, Henrique B.; Mathieu, Patrick
    OBJECTIVES: The objective of this study was to determine the prognostic value of combined measures of B-type natriuretic peptide (BNP) and high-sensitivity cardiac troponin T (hsTnT) in patients with low-flow, low-gradient aortic stenosis (LF-LG AS) who had either a preserved or reduced left ventricular ejection fraction (LVEF). BACKGROUND: An elevated BNP level is associated with increased risk of mortality in patients with LF-LG AS. The incremental prognostic value of hsTnT in these patients is unknown. METHODS: Ninety-eight patients (74 10 years; 75% men) with LF-LG AS (LVEF <50% and/or stroke volume index <35 ml/m2 , mean gradient <40 mm Hg, indexed aortic valve area <0.6 cm2 /m2 ) who were prospectively enrolled in the TOPAS (Truly or Pseudo-Severe Aortic Stenosis) study were included. The cohort was divided into 3 groups according to BNP and hsTnT levels: group A: BNP <550 pg/ml and hsTnT <15 ng/l; group B: BNP $550 pg/ml or hsTnT $15 ng/l; and group C: BNP $550 pg/ml and hsTnT $15 ng/l. The primary endpoint was all-cause mortality. RESULTS: Twenty-seven patients (27%) were in group A, 39 (40%) were in group B, and 32 (33%) were in group C. During a median follow-up of 2.8 years, 43 patients died. Two-year mortality was higher in group C (41 9%) than in group B (23 7%) and group A (5 4%) (p ¼ 0.002). In group B, there was no significant difference in 2-year mortality rates between the subgroup with hsTnT $15 ng/l (n ¼ 29) and the subgroup with BNP $550 pg/ml (n ¼ 10) (26 9% vs. 11 10%, respectively; p ¼ 0.21). In multivariable analysis adjusted for age, type of treatment (aortic valve replacement vs. conservative therapy), coronary artery disease, and LVEF, being in group C remained independently associated with an increased risk of mortality (hazard ratio [HR]: 4.25; p ¼ 0.023), and group B tended to have higher mortality (HR: 3.63; p ¼ 0.058) compared with group A. CONCLUSIONS: This study demonstrated the usefulness of combined measures of BNP and hsTnT to enhance risk stratification in patients with LF-LG AS. Patients with elevation of both BNP and hsTnT had a markedly increased risk of mortality. (Multicenter Prospective Study of Low-Flow Low-Gradient Aortic Stenosis [TOPAS]; NCT01835028)
  • Publication
    Accès libre
    Effect of regional upper septal hypertrophy on echocardiographic assessment of left ventricular mass and remodeling in aortic stenosis
    (ScienceDirect, 2020-10-14) Guzzetti, Ezequiel; Garcia, Julio; Larose, Éric; Shen, Mylène; Le Ven, Florent; Bédard, Élisabeth; Capoulade, Romain; Annabi, Mohamed Salah; Pibarot, Philippe; Clavel, Marie-Annick; Tastet, Lionel; Arsenault, Marie
    Background: Transthoracic echocardiography (TTE) is the reference method for evaluation of aortic stenosis (AS), and it is extensively used to quantitate left ventricular (LV) mass and volumes. Regional upper septal hypertrophy (USH) or septal bulge is a frequent finding in patients with AS and may lead to overestimation of LV mass when using linear measurements. The objective of this study was to compare estimates of LV mass obtained by two-dimensional transthoracic echocardiographic LV dimensions measured at different levels of the LV cavity with those obtained by cardiovascular magnetic resonance (CMR). Methods: One hundred six patients (mean age, 63 ± 15 years; 68% men) with AS were included in this subanalysis of the PROGRESSA study. Two-dimensional transthoracic echocardiographic measurements of LV dimensions were obtained at the basal level (BL; as recommended in guidelines), immediately below the septal bulge (BSB), and at a midventricular level (ML). Regional USH was defined as a basal interventricular septal thickness ≥ 13 mm and >1.3 times the thickness of the septal wall at the ML. Agreement between transthoracic echocardiographic and CMR measures was evaluated using Bland-Altman analysis. Results: The distribution of AS severity was mild in 23%, moderate in 57%, and severe in 20% of patients. Regional USH was present in 28 patients (26%). In the whole cohort, two-dimensional TTE overestimated LV mass (bias: BL, +60 ± 31 g; BSB, +59 ± 32 g; ML, +54 ± 32 g; P = .02). The biplane Simpson method slightly but significantly underestimated LV end-diastolic volume (bias -10 ± 20 mL, P < .001) compared with CMR. Overestimation of LV mass was more marked in patients with USH when measuring at the BL and was significantly lower when measuring LV dimensions at the ML (P < .025 vs BL and BSB). Conclusions: Two-dimensional TTE systematically overestimated LV mass and underestimated LV volumes compared with CMR. However, the bias between TTE and CMR was less important when measuring at the ML. Measurements at the BL as suggested in guidelines should be avoided, and measurements at the ML should be preferred in patients with AS, especially in those with USH.
  • Publication
    Increasing pulmonary arterial pressure at low level of exercise in asymptomatic, organic mitral regurgitation
    (Elsevier Science, 2018-02-06) Toubal, Oumhani; Dahou, Abdellaziz; O'Connor, Kim; Thébault, Christophe; Mahjoub, Haïfa; Magne, Julien; Le Ven, Florent; Beaudoin, Jonathan; Bernier, Mathieu; Pibarot, Philippe; Clavel, Marie-Annick
  • Publication
    Accès libre
    Prevalence of left ventricle non-compaction criteria in adult patients with bicuspid aortic valve versus healthy control subjects
    (BMJ Publishing Group, 2018-10-07) Guzzetti, Ezequiel; Tizón-Marcos, Helena; Larose, Éric; Shen, Mylène; Le Ven, Florent; Chetaille, Philippe; Bédard, Élisabeth; Capoulade, Romain; Pibarot, Philippe; Clavel, Marie-Annick; Tastet, Lionel; Salaun, Erwan; Arsenault, Marie
    Objective The aim of this study was to compare the prevalence of left ventricle non-compaction (LVNC) criteria (or hypertrabeculation) in a cohort of patients with bicuspid aortic valve (BAV) and healthy control subjects (CTL) without cardiovascular disease using cardiovascular MR (CMR). Methods 79 patients with BAV and 85 CTL with tricuspid aortic valve and free of known cardiovascular disease underwent CMR to evaluate the presence of LVNC criteria. The left ventricle was assessed at end-systole and end-diastole, in the short-axis, two-chamber and four-chamber views and divided into the 16 standardised myocardial segments. LVNC was assessed using the non-compacted/compacted (NC/C) myocardium ratio and was considered to be present if at least one of the myocardial segments had a NC/C ratio superior to the cut-off values defined in previous studies: Jenni et al (>2.0 end-systole); Petersen et al (>2.3 end-diastole); or Fazio et al (>2.5 end-diastole). Results 15 CTL (17.6%) vs 8 BAV (10.1%) fulfilled Jenni et al’s criterion; 69 CTL (81.2%) vs 49 BAV (62.0%) fulfilled Petersen et al’s criterion; and 66 CTL (77.6%) vs 43 BAV (54.4%) fulfilled Fazio et al’s criterion. Petersen et al and Fazio et al’s LVNC criteria were met more often by CTL (p=0.006 and p=0.002, respectively) than patients with BAV, whereas this difference was not statistically significant according to Jenni et al’s criterion (p=0.17). In multivariable analyses, after adjusting for age, sex, the presence of significant valve dysfunction (>mild stenosis or >mild regurgitation), indexed LV mass, indexed LV end-diastolic volume and LV ejection fraction, BAV was not associated with any of the three LVNC criteria. Conclusion Patients with BAV do not harbour more LVNC than the general population and there is no evidence that they are at higher risk for the development of LVNC cardiomyopathy.
  • Publication
    Transcatheter aortic valve replacement in patients with low-flow, low-gradient aortic stenosis : the TOPAS-TAVI registry
    (Elsevier Science, 2018-03-19) Dahou, Abdellaziz; Lerakis, Stamatios A.; Côté, Mélanie; Gilard, Martine; Nombela-Franco, Luis; Cavalcante, João L.; Rodés-Cabau, Josep; Makkar, Rajendra; Le Ven, Florent; Herrmann, Howard C.; Amat Santos, Ignacio J.; Windecker, Stephan; Pelletier Beaumont, Émilie; Enriquez-Sarano, Maurice; Pibarot, Philippe; Cheema, Asim; Clavel, Marie-Annick; Puri, Rishi; Ribeiro, Henrique B.; Muñoz, Antonio; García del Blanco, Bruno; Zajarias, Alan; Lisko, John C.; Hayek, Salim; Babaliaros, Vasilis; Gleason, Thomas G.; Chakravarty, Tarun; Szeto, Wilson Y.; Agustin, Alberto de; Serra, Vicenç; Schindler, John Thomas
    Background : Few data exist on patients with low-flow, low-gradient aortic stenosis (LFLG-AS) undergoing transcatheter aortic valve replacement (TAVR). Also, very scarce data exist on the usefulness of dobutamine stress echocardiography (DSE) before TAVR in these patients. Objectives : The authors sought to evaluate clinical outcomes and changes in left ventricular ejection fraction (LVEF) following TAVR in patients with classical LFLG-AS. Methods : This multicenter registry included 287 patients with LFLG-AS undergoing TAVR. DSE was performed before TAVR in 234 patients and the presence of contractile reserve was defined as an increase of ≥20% in stroke volume. Transthoracic echocardiography was repeated at hospital discharge and at 1-year follow-up. Clinical follow-up was obtained at 1 and 12 months, and yearly thereafter. Results : The median Society of Thoracic Surgeons score of the study population was 7.7% (interquartile range 5.3% to 12.0%), and the mean LVEF and transvalvular gradient were 30.1 ± 9.7% and 25.4 ± 6.6 mm Hg, respectively. The presence of contractile reserve was observed in 45% of patients at DSE. Mortality rates were 3.8%, 20.1%, and 32.3% at 30 days, 1 year, and 2 years, respectively. On multivariable analysis, chronic obstructive pulmonary disease (p = 0.022) and lower hemoglobin values (p < 0.001) were associated with all-cause mortality. Lower hemoglobin values (p = 0.004) and moderate-to-severe aortic regurgitation post-TAVR (p = 0.018) were predictors of the composite of mortality and rehospitalization due to heart failure. LVEF increased by 8.3% (95% confidence interval: 6% to 11%) at 1-year follow-up, and the lack of prior coronary artery bypass graft (p = 0.004), a lower LVEF at baseline (p < 0.001), and a lower stroke volume index at baseline (p = 0.019) were associated with greater increase in LVEF. The absence of contractile reserve at baseline DSE was not associated with any negative effect on clinical outcomes or LVEF changes at follow-up. Conclusions : TAVR was associated with good periprocedural outcomes in patients with LFLG-AS. However, approximately one-third of LFLG-AS TAVR recipients died at 2-year follow-up, with pulmonary disease, anemia, and residual paravalvular leaks associated with poorer outcomes. LVEF improved following TAVR, but DSE failed to predict clinical outcomes or LVEF changes over time. (Multicenter Prospective Study of Low-Flow Low-Gradient Aortic Stenosis [TOPAS Study]; NCT01835028)
  • Publication
    Cardiac morphology and function reference values derived from a large subset of healthy young Caucasian adults by magnetic resonance imaging
    (European Association of Echocardiography, 2015-09-09) De Larochellière, Élianne; Tizón-Marcos, Helena; Larose, Éric; Bibeau, Karine; Le Ven, Florent; Pibarot, Philippe; Deschepper, Christian F.; Bissonnette, Stéphanie.
    Aims: Assessment of cardiac anatomy and function by cardiovascular magnetic resonance (CMR) is accurate and reproducible and is commonly performed to clarify borderline results obtained by other techniques. Normal reference values are lacking in a large sample of young healthy adults. As CMR is increasingly solicited to discriminate normality from equivocal disease in this population, we sought to determine reliable reference values. Methods and results: A sample of 434 Caucasian adults aged 26 ± 4 years (45% male) without cardiovascular disease or risk factors (including obesity and smoking) underwent CMR. Blood pressure, electrocardiogram, and plasma markers (lipid profile, fasting glucose, troponin, and Nt-pro-BNP) were within normal limits and typical of a low-cardiometabolic-risk profile. End-diastolic (ED), end-systolic (ES), and stroke volumes were greater in men for left and right atria and ventricles. Left ventricular (LV) mass was higher in men. ED wall thickness of all segments was greater in men, whereas ES wall thickening (segmental function) was similar in both genders. After normalization to body surface area, all gender differences remained. Left and right ventricular volumes were lower, and left atrial volumes were higher in older individuals. In contrast, LV mass was not associated with age. Conclusion: This is the first large database of reference ranges for ventricular and atrial functions, volumes, and mass in young Caucasian men and women devoid of cardiovascular disease and risk factors. These data will contribute to improving the accuracy of CMR interpretation for clinical and research applications.
  • Publication
    Myocardial injury after transaortic versus transapical transcatheter aortic valve replacement
    (Little, Brown & Co.,, 2015-06-01) Campelo-Parada, Francisco; Dahou, Abdellaziz; Carrasco, José Luis; Dumont, Éric; Abdul-Jawad Altisent, Omar; Rodés-Cabau, Josep; Le Ven, Florent; Mohammadi, Siamak; Paradis, Jean-Michel; Amat Santos, Ignacio J.; Doyle, Daniel; Del Trigo, Maria; Urena Alcazar, Marina; Pibarot, Philippe; Allende, Ricardo; Puri, Rishi; Ribeiro, Henrique B.; De Larochellière, Robert
    Background : The release of cardiac biomarkers of myocardial injury after transcatheter aortic valve replacement (TAVR) is common, but no data exist on patients undergoing TAVR through a transaortic approach. We aimed to evaluate the incidence and prognostic significance of the increase in cardiac biomarkers in nontransfemoral TAVR candidates, comparing transaortic and transapical approaches. Methods : After excluding patients deemed suitable for transfemoral TAVR, 251 consecutive patients (transaortic, 45; transapical, 206) were prospectively evaluated. Creatine kinase–myocardial band and cardiac troponin T levels were measured at baseline and at 6, 12, 24, 48, and 72 hours after TAVR. Baseline and 6- to 12-month echocardiographic and clinical follow-up were performed. Results : After TAVR, cardiac troponin T increased above the upper normal values in all patients (peak value 0.64 µg/L [IQR, 0.39 to 1.03 µg/L]), whereas creatine kinase–myocardial band levels increased in 88% of patients (transaortic 51%, transapical 96%, p < 0.001; peak value 20.1 µg/L [interquartile range, 14.3 to 31.6 µg/L]). Compared with the transaortic approach, the transapical approach was associated with a greater rise in both cardiac biomarkers (p < 0.001 for both), and a lesser improvement in left ventricular ejection fraction (p = 0.058) and global longitudinal strain (p = 0.039) at 6- to 12-month follow-up. Greater increases of cardiac troponin T levels were independently associated with 30-day and 1-year overall and cardiovascular mortality (p < 0.001 for all). A 15-fold rise in cardiac troponin T levels was the optimal threshold for determining poorer outcomes (p < 0.001). Conclusions : Periprocedural TAVR-related myocardial injury in nontransfemoral candidates was demonstrated in all patients, but the transapical approach was associated with significantly greater myocardial injury compared with the transaortic approach. A higher degree of myocardial injury translated into reduced left ventricular function improvement and lower early and midterm survival rates.
  • Publication
    Valve tissue characterization by magnetic resonance imaging in calcific aortic valve disease
    (Canadian Cardiology Publications., 2014-10-07) Tizón-Marcos, Helena; Larose, Éric; Le Ven, Florent; Fuchs, Christina; Pibarot, Philippe; Mathieu, Patrick
    Background: Calcific aortic valve disease affects 10%-15% of the elderly population, causing considerable morbidity and mortality. There is no imaging technique that allows for the assessment of tissue composition of the valve in vivo. We thus investigated whether multiparametric magnetic resonance imaging (MRI) could characterize and quantify lipid, fibrous, and mineralized tissues within aortic valve (AV) cusps. Methods: AV leaflets were explanted from patients with severe aortic stenosis at the time of valve replacement surgery. Aortic cusps were imaged ex vivo using 1.5 T MRI using 3 gradient-echo sequences with T1, moderate T2, and proton density weightings (T1w, T2w, and PDw). Histopathologic analysis was performed on coregistered slices to identify and measure mineralized tissue, fibrous tissue, and lipid-rich tissue. Area and mean grey values were measured in all 3 weightings by standardized software. Results: Four hundred ninety-two regions of interest from 30 AV leaflets were studied. Total leaflet surface and the areas of mineralized (P < 0.0001), fibrous (P = 0.002), and lipid-rich (P = 0.0001) tissues measured by MRI matched closely those measured by histopathologic examination. All 3 weightings provided significant discrimination between median grey values for mineralized, fibrous, and lipid-rich tissues (P < 0.0001 for T1w, moderate T2w, and PDw). A best-fit equation integrating the grey value data from all 3 weightings allowed multiparametric MRI to identify valve leaflet components with areas under the receiver operating characteristic curve of 0.92, 0.81, and 0.72, respectively. Conclusions: AV leaflet characteristics, including tissue composition, distribution, and area, may be successfully measured by multiparametric MRI with good to excellent accuracy.
  • Publication
    Characteristics of trabeculated myocardium burden in young and apparently healthy adults
    (American College of Cardiology, 2014-07-18) Bertrand, Olivier; Paz Ricapito, Maria de la; Tizón-Marcos, Helena; Larose, Éric; Bibeau, Karine; Le Ven, Florent; Bédard, Élisabeth; Sinha, Swapnil; Pasian, Sergio; Engert, James; Pibarot, Philippe; Deschepper, Christian
    Increased myocardial trabeculations define noncompaction cardiomyopathy (NCC). Imaging advancements have led to increasingly common identification of prominent trabeculations with unknown implications. We quantified and determined the impact of trabeculations' burden on cardiac function and stretch in a population of healthy young adults. One hundred adults aged 18 to 35 years (28 ± 4 years, 55% women) without known cardiovascular disease were prospectively studied by cardiovascular magnetic resonance. Left ventricular (LV) volumes, segmental function, and ejection fraction (EF) and left atrial volumes were determined. Thickness and area of trabeculated (T) and dense (D) myocardium were measured for each standardized LV segment. N-terminal pro-brain natriuretic peptide (Nt-pro-BNP) was measured. Eighteen percent of the subjects had ≥1 positive traditional criteria for NCC, and 11% meet new proposed NCC cardiovascular magnetic resonance criteria. Trabeculated over dense myocardium ratio (T/D) ratios were uniformly greater at end-diastole versus end-systole (0.90 ± 0.25 vs 0.42 ± 0.13, p <0.0001), in women versus men (0.85 ± 0.24 vs 0.72 ± 0.19, p = 0.006), at anterior versus nonanterior segments (1.41 ± 0.59 vs 0.88 ± 0.35, p <0.0001), and at apical versus nonapical segments (1.31 ± 0.56 vs 0.87 ± 0.38, p <0.0001). The largest T/D ratios were associated with lower LVEF (57.0 ± 5.3 vs 62 ± 5.5, p = 0.0001) and greater Nt-pro-BNP (203 ± 98 vs 155 ± 103, p = 0.04). Multivariable regression identified greater end-systolic T/D ratios as the strongest independent predictor of lower LVEF, beyond age and gender, left atrial or LV volumes, and Nt-pro-BNP (β = −9.9, 95% CI −15 to 4.9, p <0.001). In conclusion, healthy adults possess variable amounts of trabeculations that regularly meet criteria for NCC. Greater trabeculations are associated with decreased LV function. Apparently healthy young adults with increased trabecular burden possess evidence of mildly impaired cardiac function.