May Lee

Transcatheter Aortic Valve Implantation Impact on Clinical and Valve-Related Outcomes

Background— Transcatheter aortic valve implantation is an alternative to open heart surgery in patients with aortic stenosis. However, long-term data on a programmatic approach to aortic valve implantation remain sparse. Methods and Results— Transcatheter aortic valve implantation was performed in 168 patients (median age, 84 years) in the setting of severe aortic stenosis and high surgical risk. Access was transarterial (n=113) or, in the presence of small iliofemoral artery diameter, transapical (n=55). The overall success rate was 94.1% in this early experience. Intraprocedural mortality was 1.2%. Operative (30-day) mortality was 11.3%, lower in the transarterial group than the transapical group (8.0% versus 18.2%; P=0.07). Overall mortality fell from 14.3% in the initial half to 8.3% in the second half of the experience, from 12.3% to 3.6% (P=0.16) in transarterial patients and from 25% to 11.1% (P=0.30) in transapical patients. Functional class improved over the 1-year postprocedure period (P<0.001). Survival at 1 year was 74%. The bulk of late readmission and mortality was not procedure or valve related but rather was due to comorbidities. Paravalvular regurgitation was common but generally mild and remained stable at late follow-up. At a maximum of >3 years and a median of 221 days, structural valve failure was not observed. Conclusions— Transcatheter aortic valve implantation can result in early and sustained functional improvement in high-risk aortic stenosis patients. Late outcome is determined primarily by comorbidities unrelated to aortic valve disease.

5-Year Outcome After Transcatheter Aortic Valve Implantation

OBJECTIVES The purpose of this study was to investigate the 5-year outcome following transcatheter aortic valve implantation (TAVI). BACKGROUND Little is known about long-term outcomes following TAVI. METHODS The 5-year outcomes following successful TAVI with a balloon-expandable valve were evaluated in 88 patients. Patients who died within 30 days after TAVI were excluded. RESULTS Mean aortic valve gradient decreased from 46 ± 18 mm Hg to 10 ± 4.5 mm Hg after TAVI and 11.8 ± 5.7 mm Hg at 5 years (p for post-TAVI trend = 0.06). Mean aortic valve area increased from 0.62 ± 0.17 cm(2) to 1.67 ± 0.41 cm(2) after TAVI and 1.40 ± 0.25 cm(2) at 5 years (p for post-TAVI trend <0.01). At 5 years, 3 patients (3.4%) had moderate prosthetic valve dysfunction (moderate transvalvular regurgitation in 1, moderate stenosis in 1, and moderate mixed disease in 1). Survival rates at 1 to 5 years were 83%, 74%, 53%, 42%, and 35%, respectively. Median survival time after TAVI was 3.4 years (95% confidence interval [CI]: 2.6 to 4.3), and the risk of death was significantly increased in patients with chronic obstructive pulmonary disease (adjusted hazard ratio [HR]: 2.17; 95% CI: 1.28 to 3.70) and at least moderate paravalvular regurgitation (adjusted HR: 2.98; 95% CI: 1.44 to 6.17). CONCLUSIONS Our study demonstrated favorable long-term outcomes after TAVI. Signs of moderate prosthetic valve failure were observed in 3.4% of patients. No patients developed severe prosthetic regurgitation or stenosis. Comorbidities, notably chronic lung disease and at least moderate paravalvular regurgitation, were associated with reduced long-term survival.

Role of multislice computed tomography in transcatheter aortic valve replacement.

Transcatheter aortic valve replacement (TAVR) required precise knowledge of the anatomic dimensions and physical characteristics of the aortic valve, annulus, and aortic root. Most groups currently use angiography, transthoracic echocardiography (TTE), or transesophageal echocardiography (TEE) to assess aortic annulus dimensions and anatomy. However, multislice computed tomography (MSCT) may allow more detailed 3-dimensional assessment of the aortic root. Twenty-six patients referred for TAVR underwent MSCT. Scans were also obtained for 18 patients after TAVR. All patients underwent pre- and postprocedural aortic root angiography, TTE, and TEE. Mean differences in measured aortic annular diameters were 1.1 mm (95% confidence interval 0.5, 1.8) for calibrated angiography and TTE, -0.9 mm (95% confidence interval -1.7, -0.1 mm) for TTE and TEE, -0.3 mm (95% confidence interval -1.1, 0.6 mm) for MSCT (sagittal) and TTE, and -1.2 mm (95% confidence interval -2.2, -0.2 mm) for MSCT (sagittal) and TEE. Coronal systolic measurements using MSCT, which corresponded to angiographic orientation, were 3.2 mm (1st and 3rd quartiles 2.6, 3.9) larger than sagittal systolic measurements, which were in the same anatomic plane as standard TTE and TEE views. There was no significant association between either shape of the aortic annulus or amount of aortic valve calcium and development of perivalvular aortic regurgitation. After TAVR, the prosthesis extended to or beyond the inferior border of the left main ostium in 9 of 18 patients (50%), and in 11 patients (61%), valvular calcium was <5 mm from the left main ostium. In conclusion, MSCT identified that the aortic annulus was commonly eccentric and often oval. This may in part explain the small, but clinically insignificant, differences in measured aortic annular diameters with other imaging modalities. MSCT after TAVR showed close proximity of both the prosthesis and displaced valvular calcium to the left main ostium in most patients. Neither eccentricity nor calcific deposits appeared to contribute significantly to severity of paravalvular regurgitation after TAVR.

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

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.

Impact of coronary artery disease on outcomes after transcatheter aortic valve implantation

Background: Coronary artery disease (CAD) negatively impacts prognosis of patients undergoing surgical aortic valve replacement and revascularization is generally recommended at the time of surgery. Implications of CAD and preprocedural revascularization in the setting of transcatheter aortic valve implantation (TAVI) are not known. Method: Patients who underwent successful TAVI from January 2005 to December 2007 were retrospectively divided into five groups according to the extent of CAD assessed with the Duke Myocardial Jeopardy Score: no CAD, CAD with DMJS 0, 2, 4, and ≥6. Study endpoints included 30‐day and 1‐year survival, evolution of symptoms, left ventricular ejection fraction (LVEF), and mitral regurgitation (MR) and need of revascularization during follow‐up. Results: One hundred and thirty‐six patients were included, among which 104 (76.5%) had coexisting CAD. Thirty‐day mortality in the five study groups was respectively 6.3, 14.6, 7.1, 5.6, and 17.7% with no statistically significant difference between groups (P = 0.56). Overall survival rate at one year was 77.9% (95% CL: 70.9, 84.9) with no difference between groups (P = 0.63). Symptoms, LVEF, and MR all significantly improved in the first month after TAVI, but the extent of improvement did not differ between groups (P > 0.08). Revascularization after TAVI was uncommon. Conclusion: The presence of CAD or nonrevascularized myocardium was not associated with an increased risk of adverse events in this initial cohort. On the basis of these early results, complete revascularization may not constitute a prerequisite of TAVI. This conclusion will require re‐assessment as experience accrues in patients with extensive CAD.

Regional systems of care to optimize outcomes in patients undergoing transcatheter aortic valve replacement

OBJECTIVES This study sought to describe the development of a multicenter, transcatheter aortic valve replacement program and regional systems of care intended to optimize coordinated, efficient, and appropriate delivery of this new therapy. BACKGROUND Transcatheter aortic valve replacement (TAVR) has become an accepted treatment option for patients with severe aortic stenosis who are at high surgical risk. Regional systems of care have led to improvements in outcomes for patients undergoing intervention for myocardial infarction, cardiac arrest, and stroke. We implemented a regional system of care for patients undergoing TAVR in British Columbia, Canada. METHODS We describe a prospective observational cohort of 583 patients who underwent TAVR in British Columbia between 2012 and 2014. Regionalization of TAVR care in British Columbia refers to a centrally coordinated, funded, and evaluated program led by a medical director and a multidisciplinary advisory group that oversees planning, access to care, and quality of outcomes at the 4 provincial sites. Risk-stratified case selection for transfemoral TAVR is performed by heart teams at each site on the basis of consensus provincial indications. Referrals for lower volume and more complicated TAVR, including nontransfemoral access and valve-in-valve procedures, are concentrated at a single site. In-hospital and 30-day outcomes are reported. RESULTS The median age was 83 years (interquartile range [IQR]: 78 to 87 years) and median STS score was 6% (IQR: 4% to 8%). Transfemoral access was performed in 499 (85.6%) cases and nontransfemoral in 84 (14.4%). Transcatheter valve-in-valve procedures in for failed bioprosthetic valves were performed in 43 patients (7.4%). A balloon-expandable valve was inserted in 386 (66.2%) and a self-expanding valve in 189 (32.4%). All-cause 30-day mortality was 3.5%. All-cause in-hospital mortality and disabling stroke occurred in 3.1% and 1.9%, respectively. Median length of stay was 3 days (IQR: 3 to 6 days), with 92.8% of patients discharged directly home. CONCLUSIONS This experience demonstrates the potential benefits of a regional system of care for TAVR. Excellent outcomes were demonstrated: most patients had short in-hospital stays and were discharged directly home.

Characterizing the spectrum of in-stent restenosis: Implications for contemporary treatment

BACKGROUND Reports addressing treatment of in-stent restenosis (ISR) are principally derived from clinical trials. OBJECTIVES To characterize the spectrum of ISR in an unselected population, and to explore clinical and angiographic factors determining management. METHODS During a prespecified six-month period before the introduction of drug-eluting stents, consecutive cases of ISR that were identified during clinically driven cardiac catheterization at five hospitals offering all approved treatment modalities for ISR were prospectively registered. RESULTS ISR was identified in 363 patients; 301 (84%) had one ISR lesion and 62 (16%) had multiple lesions. Unstable clinical presentations accounted for 51%, including 15% with ST-elevation myocardial infarction. The median interval (25th, 75th percentiles) from stent insertion to angiographic diagnosis of ISR was eight months (Q1,Q3: 4,15), with a median stented length of 18 mm (Q1,Q3: 15,28). The majority of lesions (60%) displayed a diffuse ISR pattern (Mehran types 2 and 3). ISR type was independent of time to re-presentation, diabetes, arterial territory and total stent length. Treatment included percutaneous coronary intervention (PCI) alone (n=139 [38%]), PCI with brachytherapy (n=105 [29%]), medical therapy (n=60 [17%]) and coronary artery bypass graft surgery (n=59 [16%]). Medical therapy was associated with small vessel size and recurrent ISR, and coronary artery bypass graft surgery was associated with multiple lesions, as well as diffuse, occlusive and recurrent ISR. For patients treated percutaneously, PCI treatment alone was more common for focal restenosis and after ST-elevation myocardial infarction, and brachytherapy was the more common treatment for diffuse and recurrent ISR, and stable angina. CONCLUSIONS These data provide a benchmark description of the spectrum of ISR with which the impact of drug-eluting stents may be compared and better understood.