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Kalavrouziotis, Dimitri

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Kalavrouziotis

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Dimitri

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Université Laval

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PublicationRestreint

Rate, timing, correlates, and outcomes of hemodynamic valve deterioration after bioprosthetic surgical aortic valve replacement

2018-08-13, Mahjoub, Haïfa, Rodés-Cabau, Josep, Kalavrouziotis, Dimitri, Voisine, Pierre, Mohammadi, Siamak, Côté, Nancy, Yanagawa, Bobby, Girerd, Nicolas, Pibarot, Philippe, Juni, Peter, Clavel, Marie-Annick, Verma, Subodh, Puri, Rishi, Dagenais, François, Mathieu, Patrick, Salaun, Erwan

Background: The incidence of structural valve deterioration after bioprosthesis (BP) aortic valve replacement (AVR) established on the basis of reoperation may substantially underestimate the true incidence. The objective is to determine the rate, timing, correlates, and association between hemodynamic valve deterioration (HVD) and outcomes assessed by Doppler echocardiography after surgical BP AVR. Methods: A total of 1387 patients (62.2% male, 70.5±7.8 years of age) who underwent BP AVR were included in this retrospective study. Baseline echocardiography was performed at a median time of 4.1 (1.3–6.5) months after AVR. All patients had an echocardiographic follow-up ≥2 years after AVR (926 at least 5 years and 385 at least 10 years). HVD was defined by Doppler assessment as a ≥10 mm Hg increase in mean gradient or worsening of transprosthetic regurgitation ≥1/3 class. HVD was classified according to the timing after AVR: “very early,” during the first 2-years; “early,” between 2 and 5 years; “midterm,” between 5 and 10 years; and “long-term,” >10 years. Results: A total of 428 patients (30.9%) developed HVD. Among these patients, 52 (12.0%) were classified as “very early,” 129 (30.1%) as “early,” 158 (36.9%) as “midterm,” and 89 (20.8%) as “long-term” HVD. Factors independently associated with HVD occurring within the first 5 years after AVR were diabetes mellitus (P=0.01), active smoking (P=0.01), renal insufficiency (P=0.01), baseline postoperative mean gradient ≥15 mm Hg (P=0.04) or transprosthetic regurgitation ≥mild (P=0.04), and type of BP (stented versus stentless, P=0.003). Factors associated with HVD occurring after the fifth year after AVR were female sex (P=0.03), warfarin use (P=0.007), and BP type (P<0.001). HVD was independently associated with mortality (hazard ratio, 2.18; 95% CI, 1.86–2.57; P<0.001). Conclusions: HVD as identified by Doppler echocardiography occurred in one third of patients and was associated with a 2.2-fold higher adjusted mortality. Diabetes mellitus and renal insufficiency were associated with early HVD, whereas female sex, warfarin use, and stented BPs (versus stentless) were associated with late HVD.

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PublicationAccès libre

Mid-term clinical and echocardiographic results of the INSPIRIS RESILIA aortic valve : a retrospective comparison to the Magna Ease

2023-07-18, Bernard, Jérémy, Georges, Gabriel, Hecht, Sébastien, Pibarot, Philippe, Clavel, Marie-Annick, Babaki, Shervin, Kalavrouziotis, Dimitri, Mohammadi, Siamak

Objectives: The INSPIRIS aortic valve combines the RESILIA proprietary tissue preservation process and an expandable stent frame to benefit future transcatheter valve-in-valve procedures. As the INSPIRIS valve became commercially available in 2017, mid-term outcome reports are scarce. We aimed to evaluate mid-term safety and echocardiographic performance of the INSPIRIS valve in comparison to its predecessor, the Carpentier Edwards Perimount Magna Ease (ME). Methods: This study was a retrospective single-centre study. Clinical results included early postoperative outcomes, mid-term mortality and readmission for cardiovascular cause or stroke. Echocardiographic follow-up (FU) was performed at discharge and 1-3, 6, 12 and 24 months. Clinical end point analyses were accomplished with a propensity score matching analysis and FU echocardiographic data comparisons using pairwise analyses and linear mixed-effect models. Results: We included 953 patients who received an INSPIRIS (n = 488) or ME (n = 463) bioprosthesis between January 2018 and July 2021. In the matched population (n = 217 per group), no significant difference in short-term outcomes was observed, survival was similar at 30 months (INSPIRIS: 94% vs ME: 91%, P = 0.89), but freedom from readmission was higher in the INSPIRIS group (94% vs 86%, P = 0.014). INSPIRIS valves had a lower gradient at discharge (∼10 vs 14 mmHg, P < 0.001), 1-3 months (∼10 vs 12 mmHg, P < 0.001) and 24 months (∼11 vs 17 mmHg, P < 0.001) in paired analyses and significantly lower evolution of mean transvalvular gradients compared to ME. Conclusions: This study represents the largest comparative evaluation of the INSPIRIS to the ME valves, which demonstrated safe clinical outcomes and favourable haemodynamic performance at 2 years. Long-term FU is underway.

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PublicationRestreint

Pre- and post-operative stroke volume impact after surgical aortic valve replacement for severe aortic stenosis

2020-10-19, Guzzetti, Ezequiel, Poulin, Anthony, Kalavrouziotis, Dimitri, Annabi, Mohamed Salah, Pibarot, Philippe, Clavel, Marie-Annick, Dagenais, François

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RNA expression profile of calcified bicuspid, tricuspid, and normal human aortic valves by RNA sequencing

2016-10-01, Gaudreault, Nathalie, Tremblay-Marchand, Joël, Kalavrouziotis, Dimitri, Droit, Arnaud, Guauque-Olarte, Sandra, Bossé, Yohan, Seidman, Jonathan G., Pibarot, Philippe, Body, Simon C., Dagenais, François, Mathieu, Patrick

The molecular mechanisms leading to premature development of aortic valve stenosis (AS) in individuals with a bicuspid aortic valve are unknown. The objective of this study was to identify genes differentially expressed between calcified bicuspid aortic valves (BAVc) and tricuspid valves with (TAVc) and without (TAVn) AS using RNA sequencing (RNA-Seq). We collected 10 human BAVc and nine TAVc from men who underwent primary aortic valve replacement. Eight TAVn were obtained from men who underwent heart transplantation. mRNA levels were measured by RNA-Seq and compared between valve groups. Two genes were upregulated, and none were downregulated in BAVc compared with TAVc, suggesting a similar gene expression response to AS in individuals with bicuspid and tricuspid valves. There were 462 genes upregulated and 282 downregulated in BAVc compared with TAVn. In TAVc compared with TAVn, 329 genes were up- and 170 were downregulated. A total of 273 upregulated and 147 downregulated genes were concordantly altered between BAVc vs. TAVn and TAVc vs. TAVn, which represent 56 and 84% of significant genes in the first and second comparisons, respectively. This indicates that extra genes and pathways were altered in BAVc. Shared pathways between calcified (BAVc and TAVc) and normal (TAVn) aortic valves were also more extensively altered in BAVc. The top pathway enriched for genes differentially expressed in calcified compared with normal valves was fibrosis, which support the remodeling process as a therapeutic target. These findings are relevant to understand the molecular basis of AS in patients with bicuspid and tricuspid valves.

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PublicationAccès libre

Transvalvular flow, sex, and survival after valve replacement surgery in patients with severe aortic stenosis

2020-04-28, Bilodeau, Anthony, Guzzetti, Ezequiel, Kalavrouziotis, Dimitri, Zhang, Bin, Couture, Christian, Annabi, Mohamed Salah, Pibarot, Philippe, Clavel, Marie-Annick, Dagenais, François

Background : The respective impacts of transvalvular flow, gradient, sex, and their interactions on mortality in patients with severe aortic stenosis undergoing surgical aortic valve replacement (AVR) are unknown. Objectives : This study sought to compare the impact of pre-operative flow-gradient patterns on mortality after AVR and to examine whether there are sex differences. Methods : This study analyzed clinical, echocardiographic, and outcome data prospectively collected in 1,490 patients (544 women [37%]), with severe aortic stenosis and preserved left ventricular ejection fraction who underwent AVR. Results : In this cohort, 601 patients (40%) had normal flow (NF) with high gradient (HG), 405 (27%) NF with low gradient (LG), 246 (17%) paradoxical low flow (LF)/HG, and 238 (16%) LF/LG. During a median follow-up of 2.42 years (interquartile range: 1.04 to 4.29 years), 167 patients died. Patients with LF/HG exhibited the highest mortality after AVR (hazard ratio [HR]: 2.01; 95% confidence interval [CI]: 1.33 to 3.03; p < 0.01), which remained significant after multivariate adjustment (HR: 1.96; 95% CI: 1.29 to 2.98; p < 0.01). Both LF/LG and NF/LG patients had comparable outcome to NF/HG (p ≥ 0.47). Optimal thresholds of stroke volume index were obtained for men (40 ml/m2) and women (32 ml/m2). Using these sex-specific cutpoints, paradoxical LF was independently associated with increased mortality in both women (adjusted HR: 2.05; 95% CI: 1.21 to 3.47; p < 0.01) and men (adjusted HR: 1.54; 95% CI: 1.02 to 2.32; p = 0.042), whereas guidelines’ threshold (35 ml/m2) does not. Conclusions : Paradoxical LF/HG was associated with higher mortality following AVR, suggesting that a reduced flow is a marker of disease severity even in patients with HG aortic stenosis. Early surgical AVR (i.e., before gradient attains 40 mm Hg) might be preferable in these patients. Furthermore, the use of sex-specific thresholds (<40 ml/m2 for men and <32 ml/m2 for women) to define low-flow outperforms the guidelines’ threshold of 35 ml/m2 in risk stratification after AVR.

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PublicationAccès libre

Bioprosthetic mitral valve thrombosis : a multifaceted and challenging clinical and imaging spectrum

2021-11-17, Châteauneuf, Gabriel, De Larochellière, Hugo, Clavel, Marie-Annick, Kalavrouziotis, Dimitri, Charbonneau, Éric, Dagenais, François, Morin, Francis, Silva, Iria, Turgeon, Pierre-Yves, Paradis, Jean-Michel, Bernier, Mathieu, Beaudoin, Jonathan, Bergeron, Sébastien, Rodés-Cabau, Josep, Mohammadi, Siamak, Pibarot, Philippe, O'Connor, Kim, Salaun, Erwan

Subclinical leaflet thrombosis of bioprosthetic aortic valves after transcatheter aortic valve replacement has been emphasized in recent published data, but few reports have focused on bioprosthetic mitral valve thrombosis. Bioprosthetic mitral valve thrombosis is a complex and multifaceted process that is associated with a wide spectrum of clinical and imaging features. The clinical presentation ranges from incidental discovery to systemic embolic events and acute heart failure. Comprehensive transthoracic echocardiographic assessment is key for early detection of subtle changes in bioprosthetic valve morphology and / or function, and indirect signs of reduced leaflet motion such as color paucity. Transesophageal echocardiography is essential to confirm the presence of valve thrombosis. Multimodality imaging is gaining increased acceptance for the evaluation of systemic embolism and for ruling out infective endocarditis using cardiac and extracardiac anatomical and metabolic imaging. This report illustrates both : 1) the spectrum of clinical and imaging characteristics associated with mitral bioprosthetic valve thrombosis ; and 2) the case-by-case management of this challenging condition by the heart team.

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PublicationAccès libre

Long-term echocardiographic data, mechanisms of failure, and reintervention outcomes of the Epic valve in mitral position : a large observational cohort

2023-07-07, Bernard, Jérémy, Kalavrouziotis, Dimitri, Salaun, Erwan, Babaki, Shervin, Clavel, Marie-Annick, Rodés-Cabau, Josep, Pibarot, Philippe, Mohammadi, Siamak

Objectives: Long-term echocardiographic reports on mitral valve (MV) porcine xenograft bioprosthesis (Epic) are lacking, and postreintervention outcomes of failed Epic are unknown. We aimed to assess the mechanisms and independent predictors of Epic failures and to compare short- and mid-term outcomes according to reintervention type. Methods: We included consecutive patients (n = 1397; mean age: 72 ± 8 years; 46% female; mean follow-up: 4.8 years) who received the Epic during mitral valve replacement (MVR) at our institution. Clinical, echocardiographic, reintervention, and outcomes data were retrieved from our prospective institution's database or government statistics. Results: Gradients and effective orifice area of the Epic were stable over 5-years follow-up. A total of 70 (5%) patients had a MV reintervention at median follow-up of 3.0 (0.7-5.4) years due to prosthesis failure, by redo-MVR (n = 38; 54%), valve-in-valve (n = 19; 27%), paravalvular leak (PVL) closure (n = 12; 17%), or thrombectomy (n = 1). Mechanisms of failure were 27 (1.9%) structural valve deterioration (SVD; all leaflet tear); 16 (1.1%) non-SVD (15 PVL, 1 pannus); 24 (1.7%) endocarditis; and 4 (0.3%) thrombosis. Freedom from all-cause and SVD-related MV reintervention at 10 years are 88% and 92%, respectively. Independent predictors of reintervention were age, baseline atrial fibrillation, initial MV etiology, and moderate or greater PVL at discharge (all P ≤ .05). Comparison of redo-MVR and valve-in-valve revealed no significant difference in early outcomes or mid-term mortality (all P ≥ .16). Conclusions: The Epic Mitral valve has stable hemodynamics through 5 years and is associated with low incidence of SVD and reintervention, mostly due to endocarditis and leaflet tear without calcification. Reintervention type had no influence on early outcomes and mid-term mortality.

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PublicationRestreint

Impact of left ventricular dysfunction in patients with high and low gradient severe aortic stenosis following transcatheter aortic valve replacement

2020-11-04, Alperi, Alberto, Faroux, Laurent, Ternacle, Julien, Muntane Carol, Guillem, De Larochellière, Robert, Paradis, Jean-Michel, Kalavrouziotis, Dimitri, Mohammadi, Siamak, Beaudoin, Jonathan, Bernier, Mathieu, Dumont, Éric, Côté, Nancy, Côté, Mélanie, Vincent, Flavien, Clavel, Marie-Annick, Rodés-Cabau, Josep, Pibarot, Philippe

Background: Outcomes of transcatheter aortic valve replacement (TAVR) in patients with high-gradient (HG) severe aortic stenosis (AS) and reduced left-ventricular (LV) ejection fraction (EF) are unknown. Methods: Patients undergoing TAVR for native severe AS between 2009 and 2018 were retrospectively included and classified into 3 groups: HG (≥ 40 mm Hg) and preserved EF (≥ 50%), HG low EF (< 50%), and low gradient (LG < 40 mm Hg) low EF. The primary endpoint was a composite of cardiovascular mortality and readmission for heart failure at 1 year after TAVR. Results: Of the 526 patients included, 323 (61%) had HG preserved EF, 69 (13%) had HG low EF, and 134 (26%) had LG low EF. HG low EF group had higher prevalence of atrial fibrillation and heart failure and higher Society of Thoracic Surgeons score compared with the HG preserved EF group. Patients in the LG low EF group were older and had higher prevalence of coronary artery disease compared with those in the HG groups. All-cause mortality at 30 days (4.0%) was similar across the 3 groups. After adjustment, the risk of primary endpoint was similar in the HG low-EF vs preserved EF groups. Conversely, the risk of primary endpoint was higher in the LG low EF group vs the HG preserved EF group (hazard ratio [HR], 2.24; 95% confidence interval [CI],1.36-3.70; P = 0.002) and vs HG low EF group (HR, 3.50; 95% CI, 1.55-7.90; P = 0.003), whereas the risk of all-cause mortality was similar across the 3 groups. Conclusions: The outcome of patients with HG low EF severe AS following TAVR is as good as that of patients with HG preserved EF

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PublicationAccès libre

Hemodynamic and clinical outcomes in redo-surgical aortic valve replacement vs. transcatheter valve-in-valve

2022-10-28, Hecht, Sébastien, Zenses, Anne-Sophie, Bernard, Jérémy, Tastet, Lionel, Côté, Nancy, Guimaraes, Leonardo, Paradis, Jean-Michel, Beaudoin, Jonathan, O'Connor, Kim, Bernier, Mathieu, Dumont, Éric, Kalavrouziotis, Dimitri, De Larochellière, Robert, Mohammadi, Siamak, Clavel, Marie-Annick, Rodés-Cabau, Josep, Salaun, Erwan, Pibarot, Philippe

Background Transcatheter valve-in-valve replacement (ViV-TAVR) has emerged as an alternative to redo-surgical aortic valve replacement (Redo-SAVR) for the treatment of failed surgical aortic bioprostheses. However, the benefit of ViV-TAVR compared with Redo-SAVR remains debated with regard to short-term hemodynamic results and short- and long-term clinical outcomes. Objective This study aimed to compare short-term hemodynamic performance and long-term clinical outcomes of ViV-TAVR vs. Redo-SAVR in patients treated for surgical aortic bioprosthetic valve failure. Methods We retrospectively analyzed the data prospectively collected in 184 patients who underwent Redo-SAVR or ViV-TAVR. Transthoracic echocardiography was performed before and after the procedure and analyzed in an echocardiography core laboratory using the new Valve Academic Research Consortium-3 criteria. An inverse probability of treatment weighting was used to compare the outcomes between both procedures. Results ViV-TAVR showed lower rate of intended hemodynamic performance (39.2% vs. 67.7%, p < 0.001) at 30 days, which was essentially driven by a higher rate (56.2% vs. 28.8%, p = 0.001) of high residual gradient (mean transvalvular gradient ≥20 mm Hg). Despite a trend for higher 30-day mortality in the Redo-SAVR vs. ViV-TAVR group (8.7% vs. 2.5%, odds ratio [95% CI]: 3.70 [0.77-17.6]; p = 0.10), the long-term mortality was significantly lower (24.2% vs. 50.1% at 8 years; hazard ratio [95% CI]: 0.48 [0.26-0.91]; p = 0.03) in the Redo-SAVR group. After inverse probability of treatment weighting analysis, Redo-SAVR remained significantly associated with reduced long-term mortality compared with ViV-TAVR (hazard ratio [95% CI]: 0.32 [0.22-0.46]; p < 0.001). Conclusions ViV-TAVR was associated with a lower rate of intended hemodynamic performance and numerically lower mortality at 30 days but higher rates of long-term mortality compared with Redo-SAVR.

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PublicationRestreint

Transcatheter aortic valve implantation in patients with severe aortic stenosis and small aortic annulus

2011-08-30, Dumont, Éric, De Larochellière, Robert, Rodés-Cabau, Josep, Kalavrouziotis, Dimitri, Bagur, Rodrigo Hernan, Doyle, Daniel, Pibarot, Philippe

Objectives: Valve hemodynamics and clinical outcomes among patients with a small aortic annulus who underwent transcatheter aortic valve implantation (TAVI) were examined. Background: The presence of a small aortic annulus may complicate the surgical management of patients with severe aortic stenosis (AS). TAVI is an alternative to aortic valve replacement (AVR) in high-risk patients, but few data exist on the results of TAVI in patients with a small aortic annulus. Methods: Between 2007 and 2010, 35 patients (mean age 79.2 ± 9.4 years) with severe AS and an aortic annulus diameter <20 mm (mean 18.5 ± 0.9 mm) underwent TAVI with a 23-mm Edwards SAPIEN bioprosthesis (Edwards Lifesciences, Inc., Irvine, California). Echocardiographic parameters and clinical outcomes were assessed prior to discharge and at 6, 12, and 24 months. Results: Procedural success was achieved in 34 patients (97.1%). There was 1 in-hospital death. Peak and mean transaortic gradients decreased from 76.3 ± 33.0 mm Hg and 45.2 ± 20.6 mm Hg at baseline to 21.8 ± 8.4 mm Hg and 11.7 ± 4.8 mm Hg post-procedure, respectively, both p < 0.0001. Mean indexed effective orifice area (IEOA) increased from 0.35 ± 0.10 cm2/m2 at baseline to 0.90 ± 0.18 cm2/m2 post-procedure, p < 0.0001. Severe prosthesis–patient mismatch (IEOA <0.65 cm2/m2) occurred in 2 patients (5.9%). At a mean follow-up of 14 ± 11 months, gradients remained low and 30 of the 31 remaining survivors were in New York Heart Association functional class I or II. Conclusions: In high-risk patients with severe AS and a small aortic annulus, TAVI is associated with good post-procedural valve hemodynamics and clinical outcomes. TAVI may provide a reasonable alternative to conventional AVR in elderly patients with a small aortic annulus.