Faculty Bibliography
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145
Early Multinational Experience of Transcatheter Tricuspid Valve Replacement for Treating Severe Tricuspid Regurgitation
OBJECTIVES:The aim of this registry was to evaluate the feasibility and safety of transcatheter tricuspid valve implantation (TTVI) in patients with extreme surgical risk. BACKGROUND:Isolated tricuspid regurgitation (TR) surgery is associated with high in-hospital mortality. METHODS:Thirty consecutive patients (mean age 75 ± 10 years; 56% women) from 10 institutions, with symptomatic functional TR, had institutional and notified body approval for compassionate use of the GATE TTVI system. Baseline, discharge, and 30-day follow-up echocardiographic data and procedural, in-hospital, and follow-up clinical outcomes were collected. RESULTS:At baseline, all patients had multiple comorbidities, severe or greater TR, and reduced baseline right ventricular function. Technical success was achieved in 26 of 30 patients (87%). Device malpositioning occurred in 4 patients, with conversion to open heart surgery in 2 (5%). Of those who received the device, 100% had reductions in TR of ≥1, and 75% experienced reductions of ≥2 grades, resulting in 18 of 24 of patients (76%) with mild or less TR at discharge. All patients had mild or less central TR. There was continued improvement in TR grade between discharge and 30 days in 15 of 19 patients (79%). In-hospital mortality was 10%. At mean follow-up of 127 ± 82 days, 4 patients (13%) had died. Of patients alive at follow-up, 62% were in New York Heart Association functional class I or II, with no late device-related adverse events. CONCLUSIONS:Compassionate treatment of severe, symptomatic functional TR using a first-generation TTVI device is associated with significant reduction in TR and improvement in functional status with acceptable in-hospital mortality. Further studies are needed to determine the appropriate patient population and long-term outcomes with TTVI therapy.
PMID: 33153565
ISSN: 1876-7605
CID: 5450462
Transcatheter Mitral Valve Replacement With the Transseptal EVOQUE System
OBJECTIVES:The aim of this study was to examine the initial experience with a novel transseptal transcatheter mitral valve replacement (TMVR) system. BACKGROUND:Transseptal TMVR may offer a less invasive option than surgery for mitral regurgitation (MR) with greater efficacy and fewer anatomic limitations than transcatheter repair. METHODS:Patients were treated with the EVOQUE TMVR system from September 2018 to October 2019. Key inclusion criteria were moderate or greater MR, New York Heart Association functional class ≥II, and high or prohibitive surgical risk. The primary outcome was technical success, defined by Mitral Valve Academic Research Consortium criteria. RESULTS:Fourteen patients were treated, all with at least moderate to severe MR. The median age was 84 years, and the median Society of Thoracic Surgeons score was 4.6%. MR was degenerative in 4 (28.6%), functional in 3 (21.4%), and mixed in 7 (50%). Technical success was achieved in 13 patients (92.9%), and 1 patient was converted to surgery. At 30 days there was 1 noncardiovascular mortality (7.1%), 2 strokes (14.3%), no myocardial infarctions, and no rehospitalizations. Two patients (14.3%) underwent paravalvular leak closure. One patient (7.1%) underwent alcohol septal ablation for left ventricular outflow tract obstruction. Including the 2 patients with paravalvular leak closure, MR was mild or less in all implanted patients at 30 days, with no MR in 10 (83.3%). Mean mitral gradient was 5.8 mm Hg (median). New York Heart Association functional class improved to ≤II in 9 patients (81.8%). CONCLUSIONS:This first-in-human experience has demonstrated the feasibility of the transseptal EVOQUE TMVR system. Further clinical studies are required to establish safety and clinical outcomes.
PMID: 33092713
ISSN: 1876-7605
CID: 5450452
Impact of brain protection strategies on mortality and stroke in patients undergoing aortic arch repair with hypothermic circulatory arrest: evidence from the Canadian Thoracic Aortic Collaborative
OBJECTIVES:The aim of this study was to investigate the impact of various brain perfusion techniques and nadir temperature cooling strategies on outcomes after aortic arch repair in a contemporary, multicentre cohort. METHODS:A total of 2520 patients underwent aortic arch repair with hypothermic circulatory arrest (HCA) between 2002 and 2018 in 11 centres of the Canadian Thoracic Aortic Collaborative. Primary outcomes included mortality; stroke; a composite of mortality or stroke; and a Society of Thoracic Surgeons-defined composite (STS-COMP) end point for mortality or major morbidity including stroke, reoperation, renal failure, prolonged ventilation and deep sternal wound infection. Multivariable logistic regression and propensity score matching were performed for cerebral perfusion and nadir temperature practices. RESULTS:Antegrade cerebral perfusion was found on multivariable analysis to be protective against mortality [odds ratio (OR) 0.64, 95% confidence interval (CI) 0.48-0.86; P = 0.005], stroke (OR 0.55, 95% CI 0.37-0.81; P = 0.006), composite of mortality or stroke (OR 0.57, 95% CI 0.45-0.72; P = 0.0001) and STS-COMP (OR 0.53, 95% CI 0.41-0.67; P < 0.0001), as compared to HCA alone. Retrograde cerebral perfusion yielded similar outcomes as compared to antegrade cerebral perfusion. When compared to HCA with nadir temperature <24°C, a propensity score analysis of 647 matched pairs identified nadir temperature ≥24°C as predictor of lower mortality (OR 0.62, 95% CI 0.40-0.98; P = 0.04), stroke (OR 0.51, 95% CI 0.31-0.84; P = 0.008), composite of mortality or stroke (OR 0.62, 95% CI 0.43-0.89; P = 0.01) and STS-COMP (OR 0.64, 95% CI 0.49-0.85; P = 0.002). CONCLUSIONS:Antegrade cerebral perfusion and nadir temperature ≥24°C during HCA for aortic arch repair are predictors of improved survival and neurological outcomes.
PMID: 32034910
ISSN: 1873-734x
CID: 5450362
Valve-Sparing Root Replacement Versus Composite Valve Grafting in Aortic Root Dilation: A Meta-Analysis
BACKGROUND:Aortic valve-sparing operations theoretically have fewer stroke and bleeding complications but may increase late reoperation risk versus composite valve grafts. METHODS:We meta-analyzed all studies comparing aortic valve-sparing (reimplantation and remodelling) and composite valve-grafting (bioprosthetic and mechanical) procedures. Early outcomes were all-cause mortality, reoperation for bleeding, myocardial infarction, and thromboembolism/stroke. Long-term outcomes included all-cause mortality, reintervention, bleeding, and thromboembolism/stroke. Studies exclusively investigating dissection or pediatric populations were excluded. RESULTS:A total of 3794 patients who underwent composite valve grafting and 2424 who underwent aortic valve-sparing procedures were included from 9 adjusted and 17 unadjusted observational studies. Mean follow-up was 5.8 ± 3.0 years. Aortic valve sparing was not associated with any difference in early mortality, bleeding, myocardial infarction, or thromboembolic complications. Late mortality was significantly lower after valve sparing (incident risk ratio, 0.68; 95% confidence interval [CI], 0.54-0.87; P < .01). Late thromboembolism/stroke (incident rate ratio, 0.36; 95% CI, 0.22-0.60; P < .01) and bleeding (incident rate ratio, 0.21; 95% CI, 0.11-0.42; P < .01) risks were lower after valve sparing. Procedure type did not affect late reintervention. CONCLUSIONS:Aortic valve sparing appears to be safe and associated with reduced late mortality, thromboembolism/stroke, and bleeding compared with composite valve grafting. Late durability is equivalent. Aortic valve sparing should be considered in patients with favorable aortic valve morphology.
PMID: 31981499
ISSN: 1552-6259
CID: 5450352
Journal of thoracic & cardiovascular surgery. 2020:159(6):2230-2240.e15.DOI: 10.1016/j.jtcvs.2019.06.040
Cost-effectiveness of coronary artery bypass grafting plus mitral valve repair versus coronary artery bypass grafting alone for moderate ischemic mitral regurgitation
OBJECTIVE:The Cardiothoracic Surgical Trials Network reported that left ventricular reverse remodeling at 2 years did not differ between patients with moderate ischemic mitral regurgitation randomized to coronary artery bypass grafting plus mitral valve repair (n = 150) or coronary artery bypass grafting alone (n = 151). To address health resource use implications, we compared costs and quality-adjusted survival. METHODS:We used individual patient data from the Cardiothoracic Surgical Trials Network trial on survival, hospitalizations, quality of life, and US hospitalization costs to estimate cumulative costs and quality-adjusted life years. A microsimulation model was developed to extrapolate to 10 years. Bootstrap and deterministic sensitivity analyses were performed to address uncertainty. RESULTS:In-hospital costs were $59,745 for coronary artery bypass grafting plus mitral valve repair versus $51,326 for coronary artery bypass grafting alone (difference $8419; 95% uncertainty interval, 2259-18,757). Two-year costs were $81,263 versus $67,341 (difference 13,922 [2370 to 28,888]), and quality-adjusted life years were 1.35 versus 1.30 (difference 0.05; -0.04 to 0.14), resulting in an incremental cost-effectiveness ratio of $308,343/quality-adjusted life year for coronary artery bypass grafting plus mitral valve repair. At 10 years, its costs remained higher ($107,733 vs $88,583, difference 19,150 [-3866 to 56,826]) and quality-adjusted life years showed no difference (-0.92 to 0.87), with 5.08 versus 5.08. The likelihood that coronary artery bypass grafting plus mitral valve repair would be considered cost-effective at 10 years based on a cost-effectiveness threshold of $100K/quality-adjusted life year did not exceed 37%. Only when this procedure reduces the death rate by a relative 5% will the incremental cost-effectiveness ratio fall below $100K/quality-adjusted life year. CONCLUSIONS:The addition of mitral valve repair to coronary artery bypass grafting for patients with moderate ischemic mitral regurgitation is unlikely to be cost-effective. Only if late mortality benefits can be demonstrated will it meet commonly used cost-effectiveness criteria.
PMID: 31375378
ISSN: 1097-685x
CID: 5451272
Inequity in Access to Transcatheter Aortic Valve Replacement: A Pan-Canadian Evaluation of Wait-Times
BACKGROUND:There has been an exponential increase in the demand for transcatheter aortic valve replacement (TAVR). Our goal was to examine trends in TAVR capacity and wait-times across Canada. METHODS:All TAVR cases were identified from April 1, 2014, to March 31, 2017. Wait-time was defined as the duration in days from the initial referral to the TAVR procedure. TAVR capacity was defined as the number of TAVR procedures per million population/province/fiscal year. We performed multivariable multilevel Cox proportional hazards modelling of the time to TAVR as the dependant variable and the effect of provinces as random effects. We quantified the variation in wait-times among provinces using the median hazard ratio. RESULTS:We identified a total of 4906 TAVR procedures across 9 provinces. Despite a year over year increase in overall capacity, there was a greater than 3-fold difference in capacity between provinces. Crude median wait-times increased over time in all provinces, with marked variation from 71.5 days in Newfoundland to 190.5 and 203 days in Manitoba and Alberta, respectively. This suggests increasing demand outpaced the growth in capacity. We found a median hazard ratio of 1.62, indicating that in half of the possible pairwise comparisons, the time to TAVR for identical patients was at least 62% longer between different provinces. CONCLUSION:We found substantial geographic inequity in TAVR access. This calls for policy makers, clinicians, and administrators across Canada to address this inequity through revaluation of provincial funding mechanisms, as well as implementation of efficient care pathways.
PMID: 32349882
ISSN: 1916-7075
CID: 5450402
Transfemoral Transcatheter Tricuspid Valve Replacement [Case Report]
PMID: 32171717
ISSN: 1876-7605
CID: 5450372
Frailty and Bleeding in Older Adults Undergoing TAVR or SAVR: Insights From the FRAILTY-AVR Study
OBJECTIVES:The aim of this study was to examine the value of frailty to predict in-hospital major bleeding and determine its impact on mid-term mortality following transcatheter (TAVR) or surgical (SAVR) aortic valve replacement. BACKGROUND:Bleeding complications are harbingers of mortality and major morbidity in patients undergoing TAVR or SAVR. Despite the high prevalence of frailty in this population, little is known about its effects on bleeding risk. METHODS:A post hoc analysis was performed of the multinational FRAILTY-AVR (Frailty Aortic Valve Replacement) cohort study, which prospectively enrolled older adults ≥70 years of age undergoing TAVR or SAVR. Trained researchers assessed frailty using a questionnaire and physical performance battery pre-procedure and ascertained clinical data from the electronic health record. The primary endpoint was major or life-threatening bleeding during the index hospitalization, and the secondary endpoint was units of packed red blood cells transfused. RESULTS:The cohort consisted of 1,195 patients with a mean age of 81.3 ± 6.0 years. The incidence of life-threatening bleeding, major bleeding with a clinically apparent source, and major bleeding without a clinically apparent source was, respectively, 3%, 6%, and 9% in the TAVR group and 8%, 10%, and 31% in the SAVR group. Frailty measured using the Essential Frailty Toolset was an independent predictor of major bleeding and packed red blood cell transfusions in both groups. Major bleeding was associated with a 3-fold increase in 1-year mortality following TAVR (odds ratio: 3.40; 95% confidence interval: 2.22 to 5.21) and SAVR (odds ratio: 2.79; 95% confidence interval: 1.25 to 6.21). CONCLUSIONS:Frailty is associated with post-procedural major bleeding in older adults undergoing TAVR and SAVR, which is in turn associated with a higher risk for mid-term mortality.
PMID: 32381184
ISSN: 1876-7605
CID: 5450412
Hybrid arch frozen elephant trunk repair: evidence from the Canadian Thoracic Aortic Collaborative
BACKGROUND:The frozen elephant trunk (FET) technique has become an increasingly popular strategy for aortic reconstruction in the setting of extensive thoracic aortic aneurysms or dissections. The objective of this study is to report on the Canadian experience with the FET technique in both the elective and emergent settings. METHODS:A total of 167 consecutive patients (mean age 65±13 years, 30% female, 25% re-operation) underwent elective (70%) and non-elective (30%) aortic arch reconstruction with the FET technique between May 2008 and October 2019 in six centers of the Canadian Thoracic Aortic Collaborative (CTAC). In-hospital clinical endpoints and early imaging endpoints were prospectively collected and analyzed. RESULTS:All 167 patients underwent successful FET implantation. In-hospital mortality occurred in 14 patients (8%), stroke occurred in 22 patients (13%) and temporary and permanent spinal cord ischemia (SCI) occurred in 6 (3.6%) and 3 (1.8%) patients, respectively. Prolonged mechanical ventilation was required in 35 patients (21%), renal failure requiring dialysis in 14 patients (8%) and atrial fibrillation in 59 patients (36%). The median hospital and intensive care unit (ICU) lengths of stay were 3 [interquartile range (IQR): 1, 6] and 10 (IQR: 7, 17) days, respectively. The rate of type 1A endoleak was 3.6%, with the lowest rate in patients who underwent a total arch replacement with a hybrid FET graft (0%) and the highest among patients who had a hemiarch with antegrade thoracic endovascular aortic repair (TEVAR) deployment (25%). The rate of other types of endoleak and stent complications was comparatively low. CONCLUSIONS:The early CTAC experience with the FET operation demonstrates technical feasibility and good early clinical outcomes in elective and emergent patients. Further analysis is required to explore variations in technique and their potential impact on early and late outcomes.
PMCID:7298239
PMID: 32551251
ISSN: 2225-319x
CID: 5450422
Management of Coronary Disease in Patients with Advanced Kidney Disease
BACKGROUND:Clinical trials that have assessed the effect of revascularization in patients with stable coronary disease have routinely excluded those with advanced chronic kidney disease. METHODS:We randomly assigned 777 patients with advanced kidney disease and moderate or severe ischemia on stress testing to be treated with an initial invasive strategy consisting of coronary angiography and revascularization (if appropriate) added to medical therapy or an initial conservative strategy consisting of medical therapy alone and angiography reserved for those in whom medical therapy had failed. The primary outcome was a composite of death or nonfatal myocardial infarction. A key secondary outcome was a composite of death, nonfatal myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. RESULTS:At a median follow-up of 2.2 years, a primary outcome event had occurred in 123 patients in the invasive-strategy group and in 129 patients in the conservative-strategy group (estimated 3-year event rate, 36.4% vs. 36.7%; adjusted hazard ratio, 1.01; 95% confidence interval [CI], 0.79 to 1.29; P = 0.95). Results for the key secondary outcome were similar (38.5% vs. 39.7%; hazard ratio, 1.01; 95% CI, 0.79 to 1.29). The invasive strategy was associated with a higher incidence of stroke than the conservative strategy (hazard ratio, 3.76; 95% CI, 1.52 to 9.32; P = 0.004) and with a higher incidence of death or initiation of dialysis (hazard ratio, 1.48; 95% CI, 1.04 to 2.11; P = 0.03). CONCLUSIONS:Among patients with stable coronary disease, advanced chronic kidney disease, and moderate or severe ischemia, we did not find evidence that an initial invasive strategy, as compared with an initial conservative strategy, reduced the risk of death or nonfatal myocardial infarction. (Funded by the National Heart, Lung, and Blood Institute and others; ISCHEMIA-CKD ClinicalTrials.gov number, NCT01985360.).
PMID: 32227756
ISSN: 1533-4406
CID: 5451232
