E. Tay

Transcatheter Aortic Valve Implantation Durability of Clinical and Hemodynamic Outcomes Beyond 3 Years in a Large Patient Cohort

Background— Although short- and medium-term outcomes after transcatheter aortic valve implantation are encouraging, long-term data on valve function and clinical outcomes are limited. Methods and Results— Consecutive high-risk patients who had been declined as surgical candidates because of comorbidities but who underwent successful transcatheter aortic valve implantation with a balloon-expandable valve between January 2005 and December 2006 and survived past 30 days were assessed. Clinical, echocardiographic, and computed tomographic follow-up examinations were performed. Seventy patients who underwent successful procedures and survived longer than 30 days were evaluated at a minimum follow-up of 3 years. At a median follow-up of 3.7 years (interquartile range 3.4 to 4.3 years), survival was 57%. Survival at 1, 2, and 3 years was 81%, 74%, and 61%, respectively. Freedom from reoperation was 98.5% (1 patient with endocarditis). During this early procedural experience, 11 patients died within 30 days, and 8 procedures were unsuccessful. When these patients were included, overall survival was 51%. Transaortic pressure gradients increased from 10.0 mm Hg (interquartile range 8.0 to 12.0 mm Hg) immediately after the procedure to 12.1 mm Hg (interquartile range 8.6 to 16.0 mm Hg) after 3 years (P=0.03). Bioprosthetic valve area decreased from a mean of 1.7±0.4 cm2 after the procedure to 1.4±0.3 cm2 after 3 years (P<0.01). Aortic incompetence after implantation was trivial or mild in 84% of cases and remained unchanged or improved over time. There were no cases of structural valvular deterioration, stent fracture, deformation, or valve migration. Conclusions— Transcatheter aortic valve implantation demonstrates good medium- to long-term durability and preserved hemodynamic function, with no evidence of structural failure. The procedure appears to offer an adequate and lasting resolution of aortic stenosis in selected patients.

Transcatheter aortic valve implantation in patients with bicuspid aortic valve stenosis.

OBJECTIVESnWe evaluated transcatheter aortic valve implantation (TAVI) in high-risk patients with bicuspid aortic valve (BAV) stenosis.nnnBACKGROUNDnTAVI shows promise in the treatment of severe stenosis of triscupid aortic valves, especially in high-risk patients. However, BAV stenosis has been considered a contraindication to TAVI.nnnMETHODSnEleven patients (age 52 to 90 years) with symptomatic severe BAV stenosis underwent TAVI at 3 Canadian tertiary hospitals between May 2006 and April 2010. All patients were considered high risk for surgical aortic valve replacement. Edwards-SAPIEN transcatheter heart valves (Edwards Lifesciences, Inc., Irvine, California) were used. Transfemoral or transapical access was selected, depending on the adequacy of femoral access.nnnRESULTSnAccess was transfemoral in 7 patients and transapical in 4 patients. There were no intraprocedural complications. Significant symptomatic and hemodynamic improvement was observed in 10 of 11 patients. Baseline aortic valve area of 0.65 ± 0.17 cm(2) and mean transaortic pressure gradient of 41 ± 22.4 mm Hg were improved to 1.45 ± 0.3 cm(2) and 13.4 ± 5.7 mm Hg, respectively. Two patients had moderate perivalvular leaks. At the 30-day follow-up there were 2 deaths due to multisystem failure in 2 transapical patients. In 1 patient an undersized, suboptimally positioned, unstable valve required late conversion to open surgery.nnnCONCLUSIONSnTAVI in selected high-risk patients with severe BAV stenosis can be successfully performed with acceptable clinical outcomes but will require further evaluation.

Transcatheter aortic valve implantation: lessons from the learning curve of the first 270 high-risk patients.

Background: Transcatheter aortic valve implantation (TAVI) is a rapidly evolving strategy for therapy of aortic stenosis. We describe the effect of the learning curve from the first 270 high‐risk patients in Vancouver, Canada. Methods: Patients underwent TAVI by transfemoral (63%) or transapical (37%) routes using balloon expandable valves. The experience was divided into the first half (FH, patients 1–135) and second half (SH, patients 136–270). Results: The mean age was 83.2 ± 8 years (FH 83 ± 12 vs. SH 81 ± 7 years, P = 0.12). The mean Society of Thoracic Surgeons Score (STS) was 9.5% ± 5.2%‐ FH 10.5 vs. SH 8.5% (P = 0.01). The overall procedural success rate in the FH was 92.6%, improving to 97.8% in the SH (P = 0.05). The transfemoral procedural success improved—FH 89.3% to SH 98.8% (P = 0.01). The transapical procedural success remained high—FH 98.0% to SH 96.1% (P = 0.53). The overall 30‐day mortality was 9.6%, improving from FH 13.3% to SH 5.9% (P = 0.04). In the transfemoral cases, 30‐day mortality decreased by 56% [10.7–4.7%, P = 0.14], and similarly in transapical cases [17.6–7.8%, P = 0.14]. In‐hospital stroke occurred in 3.3% (FH 3.7% vs. SH 2.9%, P = 0.74). The overall need for a new permanent pacemaker was 5.9% (FH 5.9% vs. SH 5.9%, P = 1). The overall major vascular injury rate was 6.7% (FH 8.1% vs. SH 5.2%, P = 0.33). The overall incidence of coronary vessel occlusion was 1.1% (FH 1.5 % vs. SH 0.7%, P = 0.56). Device embolization or failure to cross the valve was rare and largely seen in the FH only. Procedural experience (>135 procedures) was an independent predictor of 30‐day survival (HR: 6.7, 95% CI: 1.2–18.1, P = 0.03). Conclusion: TAVI outcomes improve with experience and device development. While overall complication rates are low, scope remains to further reduce procedural adverse events.© 2011 Wiley Periodicals, Inc.

Multislice Computed Tomography for Prediction of Optimal Angiographic Deployment Projections During Transcatheter Aortic Valve Implantation

OBJECTIVESnThis study assessed whether multislice computed tomography (MSCT) could predict optimal angiographic projections for visualizing the plane of the native valve and facilitate accurate positioning during transcatheter aortic valve implantation (TAVI).nnnBACKGROUNDnAccurate device positioning during TAVI depends on valve deployment in angiographic projections perpendicular to the native valve plane, but these may be difficult to determine.nnnMETHODSnTwenty patients underwent MSCT before TAVI. Using a novel technique, multiple angiographic projections accurately representing the native valve plane in multiple axes were determined. The accuracy of all predicted projections was determined post-procedure using angiography according to new criteria, based on valve perpendicularity and the degree of strut overlap (defined as excellent, satisfactory, or poor). The accuracy of valve deployment using MSCT was compared with the results of 20 consecutive patients undergoing TAVI without such MSCT angle prediction.nnnRESULTSnCorrect final deployment projections were more frequent in the MSCT-guided compared with non-MSCT-guided group: excellent or satisfactory projections (90% vs. 65%, p = 0.06). The MSCT angle prediction was accurate but dependent on optimal images (optimal images: 93% of predicted angles were excellent or satisfactory, suboptimal images: 73% of predicted angles were poor). A line of perpendicularity could be generated with optimal projections across the right-to-left anterior oblique plane by adding the correct cranial or caudal angulation.nnnCONCLUSIONSnPre-procedural MSCT can predict optimal angiographic deployment projections for implantation of transcatheter valves. An ideal deployment angle curve or line of perpendicularity can be generated. Understanding and applying these principles improves the accuracy of valve deployment and may improve outcomes.

Transcatheter Closure of Paravalvular Defects Using a Purpose-Specific Occluder

OBJECTIVESnThis study sought to describe a method of paravalvular leak closure using a purpose-specific occlusion device.nnnBACKGROUNDnTranscatheter closure of paravalvular leaks has been hampered by technical challenges, the limitations of available imaging modalities, and the lack of closure devices specifically designed for this purpose.nnnMETHODSnPatients with severe symptomatic paravalvular regurgitation at high risk for repeat surgery underwent transcatheter leak closure. Both left ventricular puncture and retrograde transfemoral approaches were used with fluoroscopic and 3-dimensional transesophageal guidance. A purpose-specific occluder (Vascular Plug III, AGA Medical Corp., Plymouth, Minnesota) was used.nnnRESULTSnFive patients with severe prosthetic mitral and aortic paravalvular leaks underwent attempted closure. Implantation of the device was successfully accomplished in all. In 1 patient, the plug interfered with closure of a mechanical valve leaflet and was removed and replaced with an alternate device. Complications included pericardial bleeding in 2 patients with a transapical approach. There was no procedural mortality. At a median follow-up of 191 days (interquartile range [IQR] 169 to 203 days) all patients were alive. New York Heart Association functional class fell from 4 (IQR 3 to 4) to 2 (IQR 2 to 3), hemoglobin rose from 89 g/l (IQR 87 to 108 g/l) to 115 g/l (IQR 104 to 118 g/l), creatinine fell from 109 micromol/l (IQR 106 to 132 micromol/l) to 89 micromol/l (IQR 89 to 126 micromol/l). Median echocardiographic follow-up at 58 days (IQR 56 to 70 days) reported residual regurgitation to be reduced from grade 4 to grade 2 (IQR 1.5 to 2.25).nnnCONCLUSIONSnClosure of mitral and aortic prosthetic paravalvular leaks with the Vascular Plug III using either a transapical (mitral) or a retrograde (aortic) approach appears promising.

A High-Risk Period for Cerebrovascular Events Exists After Transcatheter Aortic Valve Implantation

OBJECTIVESnThis study assesses if there exists a high-risk period for cerebrovascular events (CeV) after transcatheter aortic valve implantation (TAVI).nnnBACKGROUNDnEven though acute strokes after TAVI have been described, it is uncertain if stroke rates continue to remain high in the early months after TAVI. Furthermore, the optimal dose and duration of thromboprophylaxis is unclear.nnnMETHODSnPatients who underwent TAVI were evaluated at baseline, at discharge, at 1 and 6 months, and yearly. Risk factors for CeV events, procedural details, and antithrombotic therapy were recorded. Outcomes assessed were CeV events and death. The timing of such events, predictors, and impact on survival were analyzed.nnnRESULTSnA total of 253 patients were assessed. Median age was 85 years. The median Society of Thoracic Surgeons score was 8.1% (interquartile range [IQR]: 5.5% to 12.0%). Risk factors included smoking (47%), hypertension (70%), dyslipidemia (66%), and diabetes mellitus (25%). Twenty-three percent had known cerebrovascular disease and 39% had atrial fibrillation. Median follow-up was 455 days (IQR: 160 to 912 days) at which time 23 patients experienced a CeV event. The incidence was highest in the first 24 h but remained high for 2 months. In-hospital mortality rate after a CeV event was 21%. A prior history of CeV disease was an independent predictor of an event (hazard ratio: 4.23, 95% CI: 1.60 to 11.11, p = 0.004).nnnCONCLUSIONSnThe incidence of CeV events is highest within 24 h of TAVI, but this risk may remain elevated for up to 2 months. A prior history of cerebrovascular disease is an independent predictor. This may have implications for patient selection and antithrombotic strategies.

Outcome of Patients After Transcatheter Aortic Valve Embolization

OBJECTIVESnThis study aims to assess the mid- to long-term follow-up of patients after valve embolization at the time of transcatheter aortic valve implantation (TAVI).nnnBACKGROUNDnTranscatheter heart valve (THV) embolization is a rare but serious complication during TAVI. Although various techniques have been developed to manage acute complications and reduce periprocedural morbidity/mortality, long-term clinical and hemodynamic consequences after these events are unknown.nnnMETHODSnPatients who developed THV embolization after TAVI were prospectively assessed. Clinical and echocardiographic characteristics were recorded at baseline and after successful TAVI/surgical aortic valve replacement. The THV migration and strut fractures/degeneration were assessed by computed tomography.nnnRESULTSnA total of 7 patients had THV embolization, all of which occurred immediately after valve deployment. The embolized THV was repositioned in the aortic arch proximal to the left subclavian artery (n = 2), immediately distal to the left subclavian artery (n = 2), and in the abdominal aorta (n = 3). A second THV was implanted successfully at the same sitting in 4 patients and at the time of a second procedure in 2 patients. Elective conventional aortic valve replacement was performed in 1 patient. Median follow-up was 1,085 days. One patient died during follow-up from an unrelated cause. The remaining 6 survivors were in New York Heart Association functional class I or II at final follow-up. Mid-term computed tomography follow-up (n = 4,591 to 1,548 days) showed that the leaflets of the embolized THV remain open in all phases of the cardiac cycle. There was also no strut fracture or migration of these valves.nnnCONCLUSIONSnClinical outcomes remain good when THV embolization is managed effectively. There are no apparent hemodynamic consequences of a second valve placed in the series. These embolized valves remain in a stable position with no evidence of strut fractures at mid-term follow-up.

Transcatheter Aortic Valve Implantation

Background—Although short- and medium-term outcomes after transcatheter aortic valve implantation are encouraging, long-term data on valve function and clinical outcomes are limited. Methods and Results—Consecutive high-risk patients who had been declined as surgical candidates because of comorbidities but who underwent successful transcatheter aortic valve implantation with a balloon-expandable valve between January 2005 and December 2006 and survived past 30 days were assessed. Clinical, echocardiographic, and computed tomographic follow-up examinations were performed. Seventy patients who underwent successful procedures and survived longer than 30 days were evaluated at a minimum follow-up of 3 years. At a median follow-up of 3.7 years (interquartile range 3.4 to 4.3 years), survival was 57%. Survival at 1, 2, and 3 years was 81%, 74%, and 61%, respectively. Freedom from reoperation was 98.5% (1 patient with endocarditis). During this early procedural experience, 11 patients died within 30 days, and 8 ...