Robert DeLarochellière

Transcatheter aortic valve implantation for the treatment of severe symptomatic aortic stenosis in patients at very high or prohibitive surgical risk: acute and late outcomes of the multicenter Canadian experience.

OBJECTIVES The aim of this study was: 1) to evaluate the acute and late outcomes of a transcatheter aortic valve implantation (TAVI) program including both the transfemoral (TF) and transapical (TA) approaches; and 2) to determine the results of TAVI in patients deemed inoperable because of either porcelain aorta or frailty. BACKGROUND Very few data exist on the results of a comprehensive TAVI program including both TA and TF approaches for the treatment of severe aortic stenosis in patients at very high or prohibitive surgical risk. METHODS Consecutive patients who underwent TAVI with the Edwards valve (Edwards Lifesciences, Inc., Irvine, California) between January 2005 and June 2009 in 6 Canadian centers were included. RESULTS A total of 345 procedures (TF: 168, TA: 177) were performed in 339 patients. The predicted surgical mortality (Society of Thoracic Surgeons risk score) was 9.8 +/- 6.4%. The procedural success rate was 93.3%, and 30-day mortality was 10.4% (TF: 9.5%, TA: 11.3%). After a median follow-up of 8 months (25th to 75th interquartile range: 3 to 14 months) the mortality rate was 22.1%. The predictors of cumulative late mortality were peri-procedural sepsis (hazard ratio [HR]: 3.49, 95% confidence interval [CI]: 1.48 to 8.28) or need for hemodynamic support (HR: 2.58, 95% CI: 1.11 to 6), pulmonary hypertension (PH) (HR: 1.88, 95% CI: 1.17 to 3), chronic kidney disease (CKD) (HR: 2.30, 95% CI: 1.38 to 3.84), and chronic obstructive pulmonary disease (COPD) (HR: 1.75, 95% CI: 1.09 to 2.83). Patients with either porcelain aorta (18%) or frailty (25%) exhibited acute outcomes similar to the rest of the study population, and porcelain aorta patients tended to have a better survival rate at 1-year follow-up. CONCLUSIONS A TAVI program including both TF and TA approaches was associated with comparable mortality as predicted by surgical risk calculators for the treatment of patients at very high or prohibitive surgical risk, including porcelain aorta and frail patients. Baseline (PH, COPD, CKD) and peri-procedural (hemodynamic support, sepsis) factors but not the approach determined worse outcomes.

Long-Term Outcomes After Transcatheter Aortic Valve Implantation Insights on Prognostic Factors and Valve Durability From the Canadian Multicenter Experience

OBJECTIVES This study sought to evaluate the long-term outcomes after transcatheter aortic valve implantation (TAVI) in the Multicenter Canadian Experience study, with special focus on the causes and predictors of late mortality and valve durability. BACKGROUND Very few data exist on the long-term outcomes associated with TAVI. METHODS This was a multicenter study including 339 patients considered to be nonoperable or at very high surgical risk (mean age: 81 ± 8 years; Society of Thoracic Surgeons score: 9.8 ± 6.4%) who underwent TAVI with a balloon-expandable Edwards valve (transfemoral: 48%, transapical: 52%). Follow-up was available in 99% of the patients, and serial echocardiographic exams were evaluated in a central echocardiography core laboratory. RESULTS At a mean follow-up of 42 ± 15 months 188 patients (55.5%) had died. The causes of late death (152 patients) were noncardiac (59.2%), cardiac (23.0%), and unknown (17.8%). The predictors of late mortality were chronic obstructive pulmonary disease (hazard ratio [HR]: 2.18, 95% confidence interval [CI]: 1.53 to 3.11), chronic kidney disease (HR: 1.08 for each decrease of 10 ml/min in estimated glomerular filtration rate, 95% CI: 1.01 to 1.19), chronic atrial fibrillation (HR: 1.44, 95% CI: 1.02 to 2.03), and frailty (HR: 1.52, 95% CI: 1.07 to 2.17). A mild nonclinically significant decrease in valve area occurred at 2-year follow-up (p < 0.01), but no further reduction in valve area was observed up to 4-year follow-up. No changes in residual aortic regurgitation and no cases of structural valve failure were observed during the follow-up period. CONCLUSIONS Approximately one-half of the patients who underwent TAVI because of a high or prohibitive surgical risk profile had died at a mean follow-up of 3.5 years. Late mortality was due to noncardiac comorbidities in more than one-half of patients. No clinically significant deterioration in valve function was observed throughout the follow-up period.

Timing, Predictive Factors, and Prognostic Value of Cerebrovascular Events in a Large Cohort of Patients Undergoing Transcatheter Aortic Valve Implantation

Background— The objective of this study was to evaluate the timing, predictive factors, and prognostic value of cerebrovascular events (CVEs) after transcatheter aortic valve implantation. Methods and Results— The study included 1061 consecutive patients who underwent transcatheter aortic valve implantation with a balloon-expandable (64%) or self-expandable (36%) valve. CVEs were classified as acute (⩽24 hours), subacute (1–30 days), or late (>30 days). CVEs occurred in 54 patients (5.1%; stroke, 4.2%) within 30 days after transcatheter aortic valve implantation (acute in 54% of cases). The predictors of acute CVEs were balloon postdilation of the valve prosthesis (odds ratio, 2.46; 95% confidence interval,1.07–5.67) and valve dislodgment/embolization (odds ratio, 4.36; 95% CI, 1.21–15.69); new-onset atrial fibrillation (odds ratio, 2.76; 95% CI, 1.11–6.83) was a predictor of subacute CVEs. Late CVEs occurred in 35 patients (3.3%; stroke, 2.1%) at a median follow-up of 12 months (3–23 months). The predictors of late CVEs were chronic atrial fibrillation (2.84; 95% CI, 1.46–5.53), peripheral vascular disease (hazard ratio, 2.02; 95% CI, 1.02–3.97), and prior cerebrovascular disease (hazard ratio, 2.04; 95% CI, 1.01–4.15). Major stroke was associated with 30-day (odds ratio, 7.43; 95% CI, 2.45–22.53) and late (hazard ratio, 1.75; 95% CI, 1.01–3.04) mortality. Conclusions— In a large cohort of patients undergoing transcatheter aortic valve implantation, the rates of acute and subacute CVEs were 2.7% and 2.4%, respectively. While balloon postdilation and valve dislodgment/embolization were the predictors of acute CVEs, new-onset atrial fibrillation determined a higher risk for subacute events. Late events were determined mainly by a history of chronic atrial fibrillation and peripheral and cerebrovascular disease. The occurrence of major stroke was associated with increased early and late mortality. These results provide important insights for the implementation of preventive measures for CVEs after transcatheter aortic valve implantation.

Incidence, predictive factors, and prognostic value of new-onset atrial fibrillation following transcatheter aortic valve implantation.

OBJECTIVES This study sought to evaluate the incidence, predictive factors, and prognostic value of new-onset atrial fibrillation (NOAF) following transcatheter aortic valve implantation (TAVI). BACKGROUND Very few data exist on the occurrence of NOAF following TAVI. METHODS A total of 138 consecutive patients with no prior history of atrial fibrillation (AF) underwent TAVI with a balloon-expandable valve. Patients were on continuous electrocardiogram monitoring until hospital discharge, and NOAF was defined as any episode of AF lasting >30 s. All clinical, echocardiographic, procedural, and follow-up data were prospectively collected. RESULTS NOAF occurred in 44 patients (31.9%) at a median time of 48 h (interquartile range: 0 to 72 h) following TAVI. The predictive factors of NOAF were left atrial (LA) size (odds ratio [OR]: 1.21 for each increase in 1 mm/m(2), 95% confidence interval [CI]: 1.09 to 1.34, p < 0.0001) and transapical approach (OR: 4.08, 95% CI: 1.35 to 12.31, p = 0.019). At 30-day follow-up, NOAF was associated with a higher rate of stroke/systemic embolism (13.6% vs. 3.2%, p = 0.021, p = 0.047 after adjustment for baseline differences between groups), with no differences in mortality rate between groups (NOAF: 9.1%, no-NOAF: 6.4%, p = 0.57). At a median follow-up of 12 months (interquartile range: 5 to 20 months), a total of 27 patients (19.6%) had died, with no differences between the NOAF (15.9%) and no-NOAF (21.3%) groups, p = 0.58. The cumulative rate of stroke and stroke/systemic embolism at follow-up were 13.6% and 15.9%, respectively, in the NOAF group versus 3.2% in the no-NOAF group (p = 0.039, adjusted p = 0.037 for stroke; p = 0.020, adjusted p = 0.023 for stroke/systemic embolism). CONCLUSIONS NOAF occurred in about one-third of the patients with no prior history of AF undergoing TAVI and its incidence was increased in patients with larger LA size and those undergoing transapical TAVI. NOAF was associated with a higher rate of stroke/systemic embolism, but not a higher mortality, at 30 days and at 1-year follow-up.

Predictive factors and long-term clinical consequences of persistent left bundle branch block following transcatheter aortic valve implantation with a balloon-expandable valve

OBJECTIVES This study evaluated the predictive factors and prognostic value of new-onset persistent left bundle branch block (LBBB) in patients undergoing transcatheter aortic valve implantation (TAVI) with a balloon-expandable valve. BACKGROUND The predictors of persistent (vs. transient or absent) LBBB after TAVI with a balloon-expandable valve and its clinical consequences are unknown. METHODS A total of 202 consecutive patients with no baseline ventricular conduction disturbances or previous permanent pacemaker implantation (PPI) who underwent TAVI with a balloon-expandable valve were included. Patients were on continuous electrocardiographic (ECG) monitoring during hospitalization and 12-lead ECG was performed daily until hospital discharge. No patient was lost at a median follow-up of 12 (range: 6 to 24) months, and ECG tracing was available in 97% of patients. The criteria for PPI were limited to the occurrence of high-degree atrioventricular block (AVB) or severe symptomatic bradycardia. RESULTS New-onset LBBB was observed in 61 patients (30.2%) after TAVI, and had resolved in 37.7% and 57.3% at hospital discharge and 6- to 12-month follow-up, respectively. Baseline QRS duration (p = 0.037) and ventricular depth of the prosthesis (p = 0.017) were independent predictors of persistent LBBB. Persistent LBBB at hospital discharge was associated with a decrease in left ventricular ejection fraction (p = 0.001) and poorer functional status (p = 0.034) at 1-year follow-up. Patients with persistent LBBB and no PPI at hospital discharge had a higher incidence of syncope (16.0% vs. 0.7%; p = 0.001) and complete AVB requiring PPI (20.0% vs. 0.7%; p < 0.001), but not of global mortality or cardiac mortality during the follow-up period (all, p > 0.20). New-onset LBBB was the only factor associated with PPI following TAVI (p < 0.001). CONCLUSIONS Up to 30% of patients with no prior conduction disturbances developed new LBBB following TAVI with a balloon-expandable valve, although it was transient in more than one third. Longer baseline QRS duration and a more ventricular positioning of the prosthesis were associated with a higher rate of persistent LBBB, which in turn determined higher risks for complete AVB and PPI, but not mortality, at 1-year follow-up.

Predictive factors, efficacy, and safety of balloon post-dilation after transcatheter aortic valve implantation with a balloon-expandable valve

OBJECTIVES This study sought to evaluate the predictive factors, effects, and safety of balloon post-dilation (BPD) for the treatment of significant paravalvular aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI). BACKGROUND Very few data exist on BPD after TAVI with a balloon-expandable valve. METHODS A total of 211 patients who underwent TAVI with a balloon-expandable valve were included. BPD was performed after TAVI if paravalvular AR ≥ 2 was identified by transesophageal echocardiography. Clinical events and echocardiographic data were prospectively recorded, and median follow-up was 12 (6 to 24) months. RESULTS BPD was performed in 59 patients (28%), leading to a reduction in at least 1 degree of AR in 71% of patients, with residual AR <2 in 54% of the patients. The predictors of the need for BPD were the degree of valve calcification and transfemoral approach, with valve calcification volume >2,200 and >3,800 mm(3) best determining the need for and a poor response to BPD, respectively. Patients who underwent BPD had a higher incidence of cerebrovascular events at 30 days (11.9% vs. 2.0%, p = 0.006), with most (83%) events within the 24 h after the procedure occurring in patients who had BPD. No significant changes in valve area or AR degree were observed at follow-up in BPD and no-BPD groups. CONCLUSIONS BPD was needed in about one-fourth of the patients undergoing TAVI with a balloon-expandable valve and was successful in about one-half of them. A higher degree of valve calcification and transfemoral approach predicted the need for BPD. BPD was not associated with any deleterious effect on valve function at mid-term follow-up, but a higher rate of cerebrovascular events was observed in patients who had BPD.

Electrocardiographic changes and clinical outcomes after transapical aortic valve implantation

BACKGROUND Transapical aortic valve implantation (TAVI) for the treatment of severe aortic stenosis requires the insertion of a large catheter through the left ventricular apex. However, the electrocardiographic (ECG) changes associated with the incision and repair of the left ventricular apex and the potential damage to the conduction system caused by implanting a balloon-expandable valve in aortic position are not known. The objective of our study was to determine the incidence, type, and timing of ECG changes associated with TAVI. METHODS The standard 12-lead ECGs of 33 consecutive patients (mean age 81 +/- 9 years, 13 men) diagnosed with symptomatic severe aortic stenosis (valve area 0.62 +/- 0.16 cm(2)) who underwent TAVI with an Edwards-SAPIEN valve were analyzed at baseline (within 24 hours before the procedure), immediately (within 6 hours) after the procedure, at hospital discharge, and at 1-month follow-up. RESULTS There were no procedural deaths, and 30-day mortality was 6%. The incidence of complete left ventricular branch block (LBBB) and left anterior hemiblock (LAHB) increased from 9% and 3% at baseline to 27% and 36% after the procedure, respectively (P < .03 for both). A lower (ventricular) position of the valve relative to the hinge point of the anterior mitral leaflet was associated with a higher incidence of new LBBB (35% vs 0%, P = .029); and a greater valve size-aortic annulus ratio, with the occurrence of new LAHB (1.20 +/- 0.07 vs 1.14 +/- 0.06, P = .021). At 1-month follow-up, the rate of LBBB and LAHB decreased to 13% and 10%, respectively (P = not significant compared with baseline). There were no cases of new atrioventricular block, and no patient needed pacemaker implantation. Transient (<48 hours) ST-elevation changes, mostly in the anterior and/or lateral leads, occurred in 6 patients (18%) immediately after the procedure; but only 1 of these patients presented new Q waves at 1-month follow-up. CONCLUSIONS Transapical aortic valve implantation was associated with a significant but transient (<1 month) increase in LBBB and LAHB, with no patient requiring pacemaker implantation. These changes were partially related to both lower (more ventricular) valve positioning and greater valve oversizing. Transient (<48 hours) ST-segment elevation changes occurred in about one fifth of the patients after the procedure, but only a minority developed new Q waves in the ECG.

Aspirin Plus Clopidogrel Versus Aspirin Alone After Coronary Artery Bypass Grafting The Clopidogrel After Surgery for Coronary Artery Disease (CASCADE) Trial

Background— Clopidogrel inhibits intimal hyperplasia in animal studies and therefore may reduce saphenous vein graft (SVG) intimal hyperplasia after coronary artery bypass grafting. The Clopidogrel After Surgery for Coronary Artery DiseasE (CASCADE) study was undertaken to evaluate whether the addition of clopidogrel to aspirin inhibits SVG disease after coronary artery bypass grafting, as assessed at 1 year by intravascular ultrasound. Methods and Results— In this double-blind phase II trial, 113 patients undergoing coronary artery bypass grafting with SVGs were randomized to receive aspirin 162 mg plus clopidogrel 75 mg daily or aspirin 162 mg plus placebo daily for 1 year. The primary outcome was SVG intimal hyperplasia (mean intimal area) as determined by intravascular ultrasound at 1 year. Secondary outcomes were graft patency, major adverse cardiovascular events, and major bleeding. One-year intravascular ultrasound and coronary angiography were performed in 92 patients (81.4%). At 1 year, SVG intimal area did not differ significantly between the 2 groups (4.1±2.0 versus 4.5±2.1 mm2, aspirin-clopidogrel versus aspirin-placebo, P=0.44). Overall 1-year graft patency was 95.2% in the aspirin-clopidogrel group compared with 95.5% in the aspirin-placebo group (P=0.90), and SVG patency was 94.3% in the aspirin-clopidogrel group versus 93.2% in the aspirin-placebo group (P=0.69). Freedom from major adverse cardiovascular events at 1 year was 92.9±3.4% in the aspirin-clopidogrel group and 91.1±3.8% in the aspirin-placebo group (P=0.76). The incidence of major bleeding at 1 year was similar for the 2 groups (1.8% versus 0%, aspirin-clopidogrel versus aspirin-placebo, P=0.50). Conclusions— Compared with aspirin monotherapy, the combination of aspirin plus clopidogrel did not significantly reduce the process of SVG intimal hyperplasia 1 year after coronary artery bypass grafting. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00228423.Background— Clopidogrel inhibits intimal hyperplasia in animal studies and therefore may reduce saphenous vein graft (SVG) intimal hyperplasia after coronary artery bypass grafting. The Clopidogrel After Surgery for Coronary Artery DiseasE (CASCADE) study was undertaken to evaluate whether the addition of clopidogrel to aspirin inhibits SVG disease after coronary artery bypass grafting, as assessed at 1 year by intravascular ultrasound. Methods and Results— In this double-blind phase II trial, 113 patients undergoing coronary artery bypass grafting with SVGs were randomized to receive aspirin 162 mg plus clopidogrel 75 mg daily or aspirin 162 mg plus placebo daily for 1 year. The primary outcome was SVG intimal hyperplasia (mean intimal area) as determined by intravascular ultrasound at 1 year. Secondary outcomes were graft patency, major adverse cardiovascular events, and major bleeding. One-year intravascular ultrasound and coronary angiography were performed in 92 patients (81.4%). At 1 year, SVG intimal area did not differ significantly between the 2 groups (4.1±2.0 versus 4.5±2.1 mm2, aspirin-clopidogrel versus aspirin-placebo, P =0.44). Overall 1-year graft patency was 95.2% in the aspirin-clopidogrel group compared with 95.5% in the aspirin-placebo group ( P =0.90), and SVG patency was 94.3% in the aspirin-clopidogrel group versus 93.2% in the aspirin-placebo group ( P =0.69). Freedom from major adverse cardiovascular events at 1 year was 92.9±3.4% in the aspirin-clopidogrel group and 91.1±3.8% in the aspirin-placebo group ( P =0.76). The incidence of major bleeding at 1 year was similar for the 2 groups (1.8% versus 0%, aspirin-clopidogrel versus aspirin-placebo, P =0.50). Conclusions— Compared with aspirin monotherapy, the combination of aspirin plus clopidogrel did not significantly reduce the process of SVG intimal hyperplasia 1 year after coronary artery bypass grafting. Clinical Trial Registration— URL: . Unique identifier: [NCT00228423][1]. # Clinical Perspective {#article-title-35} [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT00228423&atom=%2Fcirculationaha%2F122%2F25%2F2680.atom

Coronary obstruction following transcatheter aortic valve implantation: a systematic review.

OBJECTIVES This study sought to evaluate, through a systematic review of the published data, the main baseline characteristics, management, and clinical outcomes of patients suffering coronary obstruction as a complication of transcatheter aortic valve implantation (TAVI). BACKGROUND Very few data exist on coronary obstruction after TAVI. METHODS Studies published between 2002 and 2012, with regard to coronary obstruction as a complication of TAVI, were identified with a systematic electronic search. Only the studies reporting data on the main baseline and procedural characteristics, management of the complication, and clinical outcomes were analyzed. RESULTS A total of 18 publications describing 24 patients were identified. Most (83%) patients were women, with a mean age of 83 ± 7 years and a mean logistic European System for Cardiac Operative Risk Evaluation score of 25.1 ± 12.0%. Mean left coronary artery (LCA) ostium height and aortic root width were 10.3 ± 1.6 mm and 27.8 ± 2.8 mm, respectively. Most patients (88%) had received a balloon-expandable valve, and coronary obstruction occurred more frequently in the LCA (88%). Percutaneous coronary intervention was attempted in 23 cases (95.8%) and was successful in all but 2 patients (91.3%). At 30-day follow-up, there were no cases of stent thrombosis or repeat revascularization, and the mortality rate was 8.3%. CONCLUSIONS Reported cases of coronary obstruction after TAVI occurred more frequently in women, in patients receiving a balloon-expandable valve, and the LCA was the most commonly involved artery. Percutaneous coronary intervention was a feasible and successful treatment in most cases. Continuous efforts should be made to identify the factors associated with this life-threatening complication to implement the appropriate measures for its prevention.

Permanent Pacemaker Implantation After Transcatheter Aortic Valve Implantation

Background— Very few data exist on the clinical impact of permanent pacemaker implantation (PPI) after transcatheter aortic valve implantation. The objective of this study was to assess the impact of PPI after transcatheter aortic valve implantation on late outcomes in a large cohort of patients. Methods and Results— A total of 1556 consecutive patients without prior PPI undergoing transcatheter aortic valve implantation were included. Of them, 239 patients (15.4%) required a PPI within the first 30 days after transcatheter aortic valve implantation. At a mean follow-up of 22±17 months, no association was observed between the need for 30-day PPI and all-cause mortality (hazard ratio, 0.98; 95% confidence interval, 0.74–1.30; P=0.871), cardiovascular mortality (hazard ratio, 0.81; 95% confidence interval, 0.56–1.17; P=0.270), and all-cause mortality or rehospitalization for heart failure (hazard ratio, 1.00; 95% confidence interval, 0.77–1.30; P=0.980). A lower rate of unexpected (sudden or unknown) death was observed in patients with PPI (hazard ratio, 0.31; 95% confidence interval, 0.11–0.85; P=0.023). Patients with new PPI showed a poorer evolution of left ventricular ejection fraction over time (P=0.017), and new PPI was an independent predictor of left ventricular ejection fraction decrease at the 6- to 12-month follow-up (estimated coefficient, −2.26; 95% confidence interval, −4.07 to −0.44; P=0.013; R2=0.121). Conclusions— The need for PPI was a frequent complication of transcatheter aortic valve implantation, but it was not associated with any increase in overall or cardiovascular death or rehospitalization for heart failure after a mean follow-up of ≈2 years. Indeed, 30-day PPI was a protective factor for the occurrence of unexpected (sudden or unknown) death. However, new PPI did have a negative effect on left ventricular function over time.Background— Very few data exist on the clinical impact of permanent pacemaker implantation (PPI) after transcatheter aortic valve implantation. The objective of this study was to assess the impact of PPI after transcatheter aortic valve implantation on late outcomes in a large cohort of patients. Methods and Results— A total of 1556 consecutive patients without prior PPI undergoing transcatheter aortic valve implantation were included. Of them, 239 patients (15.4%) required a PPI within the first 30 days after transcatheter aortic valve implantation. At a mean follow-up of 22±17 months, no association was observed between the need for 30-day PPI and all-cause mortality (hazard ratio, 0.98; 95% confidence interval, 0.74–1.30; P =0.871), cardiovascular mortality (hazard ratio, 0.81; 95% confidence interval, 0.56–1.17; P =0.270), and all-cause mortality or rehospitalization for heart failure (hazard ratio, 1.00; 95% confidence interval, 0.77–1.30; P =0.980). A lower rate of unexpected (sudden or unknown) death was observed in patients with PPI (hazard ratio, 0.31; 95% confidence interval, 0.11–0.85; P =0.023). Patients with new PPI showed a poorer evolution of left ventricular ejection fraction over time ( P =0.017), and new PPI was an independent predictor of left ventricular ejection fraction decrease at the 6- to 12-month follow-up (estimated coefficient, −2.26; 95% confidence interval, −4.07 to −0.44; P =0.013; R 2=0.121). Conclusions— The need for PPI was a frequent complication of transcatheter aortic valve implantation, but it was not associated with any increase in overall or cardiovascular death or rehospitalization for heart failure after a mean follow-up of ≈2 years. Indeed, 30-day PPI was a protective factor for the occurrence of unexpected (sudden or unknown) death. However, new PPI did have a negative effect on left ventricular function over time. # CLINICAL PERSPECTIVE {#article-title-43}