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Journal of the American College of Cardiology | 2012

Percutaneous Aortic Valve Replacement: Vascular Outcomes With a Fully Percutaneous Procedure

Stefan Toggweiler; Ronen Gurvitch; Jonathon Leipsic; David A. Wood; Alexander B. Willson; Ronald K. Binder; Anson Cheung; Jian Ye; John G. Webb

OBJECTIVES The aim of this study was to evaluate vascular complications in a consecutive patient population undergoing transfemoral percutaneous aortic valve replacement (PAVR) applying current Valve Academic Research Consortium definitions. BACKGROUND Vascular complications have been the major cause of mortality and morbidity associated with PAVR. Both open surgical and fully percutaneous access site strategies have been advocated. METHODS All patients undergoing transfemoral PAVR during fiscal years 2009 and 2010 were prospectively evaluated at baseline, after the procedure, and at 30 days. RESULTS PAVR was performed in 137 consecutive patients. All but 1 patient underwent planned arteriotomy closure using a percutaneous pre-closure technique. Smaller sheaths, rigorous angiographic and computed tomographic screening and patient selection, and percutaneous vascular repair techniques were increasingly used over this period. From 2009 to 2010, major vascular complications decreased from 8% to 1% (p = 0.06), minor vascular complications decreased from 24% to 8% (p < 0.01), major bleeds fell from 14% to 1% (p < 0.01), and unplanned surgery decreased from 28% to 2% (p < 0.01). A minimal artery diameter smaller than the external sheath diameter, moderate or severe calcification, and peripheral vascular disease were associated with higher vascular complication rates. CONCLUSIONS Vascular complications occur more often if the minimal artery diameter is smaller than the external sheath diameter, in the presence of moderate or severe calcification, and in patients with peripheral vascular disease. With careful patient selection, advanced interventional techniques, and a fully percutaneous procedure, marked reductions in vascular and bleeding complications can be achieved.


Journal of the American College of Cardiology | 2012

3-dimensional aortic annular assessment by multidetector computed tomography predicts moderate or severe paravalvular regurgitation after transcatheter aortic valve replacement: a multicenter retrospective analysis.

Alexander B. Willson; John G. Webb; Troy LaBounty; Stephan Achenbach; Robert Moss; Miriam Wheeler; Christopher R. Thompson; James K. Min; Ronen Gurvitch; Bjarne Linde Nørgaard; Cameron J. Hague; Stefan Toggweiler; Ronald K. Binder; Melanie Freeman; Rohan S. Poulter; Steen Hvitfeldt Poulsen; David A. Wood; Jonathon Leipsic

OBJECTIVES This study sought to analyze multidetector computed tomography (MDCT) 3-dimensional aortic annular dimensions for the prediction of paravalvular aortic regurgitation (PAR) following transcatheter aortic valve replacement (TAVR). BACKGROUND Moderate or severe PAR after TAVR is associated with increased morbidity and mortality. METHODS A total of 109 consecutive patients underwent MDCT pre-TAVR with a balloon expandable aortic valve. Differences between transcatheter heart valve (THV) size and MDCT measures of annular size (mean diameter, area, and circumference) were analyzed concerning prediction of PAR. Patients with THV malposition (n = 7) were excluded. In 50 patients, MDCT was repeated after TAVR to assess THV eccentricity (1 - short diameter/long diameter) and expansion (MDCT measured THV area/nominal THV area). RESULTS Moderate or severe PAR (13 of 102) was associated with THV undersizing (THV diameter - mean diameter = -0.7 ± 1.4 mm vs. 0.9 ± 1.8 mm for trivial to mild PAR, p < 0.01). The difference between THV size and MDCT annular size was predictive of PAR (mean diameter: area under the curve [AUC]: 0.81, 95% confidence interval [CI]: 0.68 to 0.88; area: AUC: 0.80, 95% CI: 0.65 to 0.90; circumference: AUC: 0.76, 95% CI: 0.59 to 0.91). Annular eccentricity was not associated with PAR (AUC: 0.58, 95% CI: 0.46 to 0.75). We found that 35.3% (36 of 102) and 45.1% (46 of 102) of THVs were undersized relative to the MDCT mean diameter and area, respectively. THV oversizing relative to the annular area was not associated with THV eccentricity or underexpansion (oversized vs. undersized THVs; expansion: 102.7 ± 5.3% vs. 106.1 ± 5.6%, p = 0.03; eccentricity: median: 1.7% [interquartile range: 1.4% to 3.0%] vs. 1.7% [interquartile range: 1.1% to 2.7%], p = 0.28). CONCLUSIONS MDCT-derived 3-dimensional aortic annular measurements are predictive of moderate or severe PAR following TAVR. Oversizing of THVs may reduce the risk of moderate or severe PAR.


Journal of the American College of Cardiology | 2013

The Impact of Integration of a Multidetector Computed Tomography Annulus Area Sizing Algorithm on Outcomes of Transcatheter Aortic Valve Replacement A Prospective, Multicenter, Controlled Trial

Ronald K. Binder; John G. Webb; Alexander B. Willson; Marina Urena; Nicolaj C. Hansson; Bjarne Linde Nørgaard; Philippe Pibarot; Marco Barbanti; Eric Larose; Melanie Freeman; Eric Dumont; Christopher R. Thompson; Miriam Wheeler; Robert Moss; Tae-Hyun Yang; Sergio Pasian; Cameron J. Hague; Giang Nguyen; Rekha Raju; Stefan Toggweiler; James K. Min; David A. Wood; Josep Rodés-Cabau; Jonathon Leipsic

OBJECTIVES This study prospectively investigated the impact of integration of a multidetector computed tomography (MDCT) annular area sizing algorithm on transcatheter aortic valve replacement (TAVR) outcomes. BACKGROUND Appreciation of the 3-dimensional, noncircular geometry of the aortic annulus is important for transcatheter heart valve (THV) sizing. METHODS Patients being evaluated for TAVR in 4 centers underwent pre-procedural MDCT. Recommendations for balloon-expandable THV size selection were based on an MDCT sizing algorithm with an optimal goal of modest annulus area oversizing (5% to 10%). Consecutive patients who underwent TAVR with the algorithm (MDCT group) were compared with consecutive patients without the algorithm (control group). The primary endpoint was the incidence of more than mild paravalvular regurgitation (PAR), and the secondary endpoint was the composite of in-hospital death, aortic annulus rupture, and severe PAR. RESULTS Of 266 patients, 133 consecutive patients underwent TAVR (SAPIEN XT THV) in the MDCT group and 133 consecutive patients were in the control group. More than mild PAR was present in 5.3% (7 of 133) of the MDCT group and in 12.8% (17 of 133) in the control group (p = 0.032). The combined secondary endpoint occurred in 3.8% (5 of 133) of the MDCT group and in 11.3% (15 of 133) of the control group (p = 0.02), driven by the difference of severe PAR. CONCLUSIONS The implementation of an MDCT annulus area sizing algorithm for TAVR reduces PAR. Three-dimensional aortic annular assessment and annular area sizing should be considered for TAVR.


Jacc-cardiovascular Interventions | 2011

Aortic Annulus Diameter Determination by Multidetector Computed Tomography: Reproducibility, Applicability, and Implications for Transcatheter Aortic Valve Implantation

Ronen Gurvitch; John G. Webb; Ren Yuan; Mark S. Johnson; Cameron J. Hague; Alexander B. Willson; Stefan Toggweiler; David A. Wood; Jian Ye; Robert Moss; Christopher R. Thompson; Stephan Achenbach; James K. Min; Troy LaBounty; Ricardo C. Cury; Jonathon Leipsic

OBJECTIVES This study sought to determine the most reproducible multidetector computed tomography (MDCT) measurements of the aortic annulus and to determine methods to improve the applicability of these measurements for transcatheter aortic valve implantation. BACKGROUND The reproducibility and applicability of MDCT annular measurements to guide transcatheter aortic valve implantation remain unclear. METHODS Annular measurements were performed in 50 patients planed for transcatheter aortic valve implantation in multiple planes: basal ring (short- and long-axis, mean diameter, area-derived diameter), coronal, sagittal, and 3-chamber projections. A theoretical model was developed taking into account the differences between the most reproducible MDCT measurements and transesophageal echocardiography to guide valve size choice. RESULTS The most reproducible measurements were the area-derived diameter and basal ring average diameter (inter-reader intraclass correlation coefficient: 0.87 [95% confidence interval: 0.81 to 0.92] and 0.80 [95% confidence interval: 0.70 to 0.87]; respectively; intrareader >0.90 for all readers). These were generally larger than transesophageal echocardiography diameters (mean difference of 1.5 ± 1.6 mm and 1.1 ± 1.7 mm, respectively). When a strategy of valve-sizing is undertaken using these CT measurements using an echocardiographic sizing scale, a different THV size would be selected in 44% and 40% of cases, respectively. When adjusting the sizing cutoffs to account for the differences in observed diameters, this was reduced to 10% to 12% (p < 0.01 for both, respectively). CONCLUSIONS The most reproducible MDCT measurements of the annulus are the area-derived diameter and basal ring average diameter, with derived values generally larger than those obtained with echocardiography. If MDCT is used for valve sizing, a strategy incorporating these differences may be important. MDCT using these easily derived measurements may be ideally suited to sizing transcatheter aortic valves as they account for the eccentricity of the aortic annulus, are reproducible, and are noninvasive.


Jacc-cardiovascular Interventions | 2013

Transcatheter aortic valve replacement with the SAPIEN 3: a new balloon-expandable transcatheter heart valve.

Ronald K. Binder; Josep Rodés-Cabau; David A. Wood; Michael Mok; Jonathon Leipsic; Robert De Larochellière; Stefan Toggweiler; Eric Dumont; Melanie Freeman; Alexander B. Willson; John G. Webb

OBJECTIVES The aim of this study was to demonstrate the first-in-human feasibility and short-term clinical outcomes with a new balloon-expandable transcatheter heart valve (THV). BACKGROUND The SAPIEN 3 (S3) THV incorporates a paravalvular sealing system, an active 3-dimensional coaxial positioning catheter, and is compatible with a 14-F expandable sheath. METHODS The S3 THV was implanted in 15 patients with symptomatic severe aortic stenosis via femoral arterial access. Multidetector computed tomography before and after valve implantation allowed assessment of a novel annular area sizing algorithm. Clinical and echocardiographic data were obtained at baseline, discharge, and 30 days. RESULTS All 15 device implants were successful. Multidetector computed tomography estimated an aortic annular area of 4.9 ± 0.4 cm(2), predicting 9.7 ± 6.9% THV oversizing. Post-transcatheter aortic valve replacement multidetector computed tomography showed consistently symmetrical and circular THVs. Aortic valve area increased from 0.7 ± 0.2 cm(2) to 1.5 ± 0.2 cm(2) (p < 0.001), and mean transaortic gradient decreased from 42.2 ± 10.3 mm Hg to 11.9 ± 5.3 mm Hg (p < 0.001). No patient had more than mild paravalvular aortic regurgitation. Hospital discharge occurred at a median of 3 (range 2 to 12) hospital days. At 30 days there were no deaths, strokes, vascular complications, bleeds, or transfusions, although 1 patient (6.7%) required a new pacemaker. All patients were in New York Heart Association functional class I or II. CONCLUSIONS The S3 THV and delivery system might facilitate fully percutaneous implantation in a broader range of patients with the potential for more accurate positioning and less paravalvular regurgitation.


Journal of the American College of Cardiology | 2012

Transcatheter Aortic Valve Replacement: Outcomes of Patients With Moderate or Severe Mitral Regurgitation

Stefan Toggweiler; Robert H. Boone; Josep Rodés-Cabau; Karin H. Humphries; May Lee; Luis Nombela-Franco; Rodrigo Bagur; Alexander B. Willson; Ronald K. Binder; Ronen Gurvitch; Jasmine Grewal; Robert Moss; Brad Munt; Christopher R. Thompson; Melanie Freeman; Jian Ye; Anson Cheung; Eric Dumont; David A. Wood; John G. Webb

OBJECTIVES The aim of this study was to evaluate the impact of mitral regurgitation (MR) on outcomes after transcatheter aortic valve replacement (TAVR) and the impact of TAVR on MR. BACKGROUND Little is known of the influence of MR on outcomes after TAVR. METHODS The outcomes of patients with mild or less (n = 319), moderate (n = 89), and severe (n = 43) MR were evaluated after TAVR at 2 Canadian centers. RESULTS Patients with moderate or severe MR had a higher mortality rate than those with mild or less MR during the 30 days after TAVR (adjusted hazard ratio: 2.10; 95% confidence interval: 1.12 to 3.94; p = 0.02). However, the mortality rates after 30 days were similar (adjusted hazard ratio: 0.82; 95% confidence interval: 0.50 to 1.34; p = 0.42). One year after TAVR, moderate MR had improved in 58%, remained moderate in 17%, and worsened to severe in 1%, and 24% of patients had died. Severe MR had improved in 49% and remained severe in 16%, and 35% of patients had died. Multivariate predictors of improved MR at 1 year (vs. unchanged MR, worse MR, or death) were a mean transaortic gradient ≥ 40 mm Hg, functional (as opposed to structural) MR, the absence of pulmonary hypertension, and the absence of atrial fibrillation. CONCLUSIONS Moderate or severe MR in patients undergoing TAVR is associated with a higher early, but not late, mortality rate. At 1-year follow-up, MR was improved in 55% of patients with moderate or severe MR at baseline. Improvement was more likely in patients with high transaortic gradients, with functional MR, without pulmonary hypertension and without atrial fibrillation.


Journal of the American College of Cardiology | 2011

Transcatheter Valve-in-Valve Implantation for Failed Surgical Bioprosthetic Valves

Ronen Gurvitch; Anson Cheung; Jian Ye; David A. Wood; Alexander B. Willson; Stefan Toggweiler; Ronald K. Binder; John G. Webb

When bioprosthetic cardiac valves fail, reoperative valve replacement carries a higher risk of morbidity and mortality compared with initial valve replacement. Transcatheter heart valve implantation may be a viable alternative to surgical aortic valve replacement for high-risk patients with native aortic stenosis, and valve-in-valve (V-in-V) implantation has been successfully performed for failed surgical bioprostheses in the aortic, mitral, pulmonic, and tricuspid positions. Despite some core similarities to transcatheter therapy of native valve disease, V-in-V therapy poses unique clinical and anatomic challenges. In this paper, we review the challenges, selection criteria, techniques, and outcomes of V-in-V implantation.


Journal of the American College of Cardiology | 2012

Transcatheter aortic valve replacement with the St. Jude Medical Portico valve: first-in-human experience.

Alexander B. Willson; Josep Rodés-Cabau; David A. Wood; Jonathon Leipsic; Anson Cheung; Stefan Toggweiler; Ronald K. Binder; Melanie Freeman; Robert DeLarochellière; Robert Moss; Luis Nombela-Franco; Eric Dumont; Karolina Szummer; Gregory P. Fontana; Raj Makkar; John G. Webb

OBJECTIVES The purpose of this study was to demonstrate the feasibility and procedural outcomes with a new self-expanding and repositionable transcatheter heart valve. BACKGROUND Transcatheter aortic valve replacement is a viable option for selected patients with severe symptomatic aortic stenosis. However, suboptimal prosthesis positioning may contribute to paravalvular regurgitation, atrioventricular conduction block, and mitral or coronary compromise. METHODS The repositionable Portico valve (St. Jude Medical, Minneapolis, Minnesota) was implanted in 10 patients with severe aortic stenosis utilizing percutaneous femoral arterial access. Patients underwent transthoracic and transesophageal echocardiography and multidetector computed tomography before and after valve implantation. Clinical and echocardiographic follow-up was obtained at 30 days. RESULTS Device implantation was successful in all patients. Prosthesis recapture and repositioning was performed in 4 patients. Intermittent prosthetic leaflet dysfunction in 1 patient required implantation of a second transcatheter valve. There was 1 minor stroke. At 30-day follow-up, echocardiographic mean transaortic gradient was reduced from 44.9 ± 16.7 mm Hg to 10.9 ± 3.8 mm Hg (p < 0.001), and valve area increased from 0.6 ± 0.1 cm(2) to 1.3 ± 0.2 cm(2) (p < 0.001). Paravalvular regurgitation was mild or less in 9 patients (90%) and moderate in 1 patient (10%). There were no major strokes, major vascular complications, major bleeds, or deaths. No patient required pacemaker implantation. All patients were in New York Heart Association functional class II or less. CONCLUSIONS Transcatheter aortic valve replacement with the repositionable Portico transcatheter heart valve is feasible, with good short-term clinical and hemodynamic outcomes.


Eurointervention | 2011

Outcomes and complications of transcatheter aortic valve replacement using a balloon expandable valve according to the Valve Academic Research Consortium (VARC) guidelines.

Ronen Gurvitch; Stefan Toggweiler; Alexander B. Willson; Namal Wijesinghe; Anson Cheung; David Wood; Jian Ye; John G. Webb

AIMS There is heterogeneity in the reporting of procedural outcomes and complications following transcatheter aortic valve replacement (TAVR). Recently, new definitions have been proposed by the Valve Academic Research Consortium (VARC) in an effort to standardise these outcomes and improve the quality of future clinical research. The aim of this study is to report the procedural outcomes and complication rates following TAVR in a large sequential patient cohort using a balloon expandable valve according to the new VARC definitions. METHODS AND RESULTS Three hundred and ten consecutive patients undergoing TAVR were assessed, including patients forming our early historical series at the infancy of TAVR. All complication rates were re-evaluated according to VARC definitions. Mean age was 82.2 ± 8.1 years and the Society of Thoracic Surgeons score was 9.4 ± 5.7%. Transfemoral 30-day mortality was 6.8% (3.8% in the second half of the cohort) and transapical 30-day mortality was 13.7% (9.4% in the second half of the cohort). Cardiovascular 30-day mortality was 7.4% and the composite safety endpoint at 30-days was 18.4%. Device success was 80% (post-procedural valve area ≤ 1.2 cm2 in 9.7%). Failure to deliver and deploy a valve occurred in only 3.5%, with 82% (nine cases) occurring in the first half of the experience. Of those who did not meet echocardiographic criteria for device success (valve area ≤ 1.2 cm2, transaortic gradient ≥ 20 mmHg or ≥ moderate aortic incompetence), 90% achieved a New York Heart Association class I/II. Life threatening bleeding complications occurred in 8.4%. In 7.7% of patients, red blood cell transfusions were given without evidence of overt bleeding. Major strokes occurred in 2.3% and acute kidney injury occurred in 6.5%. CONCLUSIONS The VARC consensus guidelines provide a standardised reporting framework for clinical endpoints and complications post TAVR. We report the first series to our knowledge of 30-day outcomes using these definitions utilising a balloon expandable valve system.


Journal of the American College of Cardiology | 2012

Sex Differences in Mortality After Transcatheter Aortic Valve Replacement for Severe Aortic Stenosis

Karin H. Humphries; Stefan Toggweiler; Josep Rodés-Cabau; Luis Nombela-Franco; Eric Dumont; David A. Wood; Alexander B. Willson; Ronald K. Binder; Melanie Freeman; May K. L. Lee; Min Gao; Mona Izadnegahdar; Jian Ye; Anson H. Cheung; John G. Webb

OBJECTIVES The aim of this study was to examine sex differences in outcome after transcatheter aortic valve replacement (TAVR) with real-world data from 2 large centers in Canada. BACKGROUND Transcatheter aortic valve replacement is an effective alternative to surgical valve replacement in symptomatic patients with severe aortic stenosis, but the impact of sex on outcomes remains unclear. The PARTNER (Placement of Aortic Transcatheter Valves) 1A trial demonstrated greater benefit of TAVR over surgery in women, but whether this was due to the poorer surgical outcome of women or better TAVR outcome, compared with men, is unknown. METHODS Consecutive patients (n = 641) undergoing TAVR in Vancouver and Quebec City, Canada, were evaluated. Differences in all-cause mortality were examined with Kaplan-Meier estimates, adjusted logistic regression, and proportional hazards models. RESULTS Women comprised 51.3% of the cohort. Balloon-expandable valves were used in 97% of cases, with transapical approach in 51.7 % women and 38.1% men. Women had more major vascular complications (12.4% vs. 5.4%, p = 0.003) and borderline significantly more major/life-threatening bleeds (21.6% vs. 15.8%, p = 0.08). At baseline, women had higher aortic gradients and worse renal function but better ejection fractions. Men had more comorbidities: prior myocardial infarction, prior revascularization, and chronic obstructive pulmonary disease. The adjusted odds ratio for 30-day all-cause mortality favored women, 0.39 (95% confidence interval: 0.19 to 0.80; p = 0.01), and this benefit persisted for 2 years, hazard ratio 0.60 (95% confidence interval: 0.41 to 0.88; p = 0.008). CONCLUSIONS Female sex is associated with better short- and long-term survival after TAVR. Added to the PARTNER 1A findings, these results suggest TAVR might be the preferred treatment option for elderly women with symptomatic severe aortic stenosis.

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Jonathon Leipsic

University of British Columbia

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David A. Wood

University of British Columbia

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Ronald K. Binder

University of British Columbia

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Melanie Freeman

University of British Columbia

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Robert Moss

University of British Columbia

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Ronen Gurvitch

Royal Melbourne Hospital

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Christopher R. Thompson

University of British Columbia

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