Simard, Trevor

AbstractBackgroundElevated transmitral gradient post transcatheter mitral valve edge‐to‐edge repair (TEER) has been associated with worse outcomes. Whether an elevated baseline transmitral diastolic mean gradient (MG) ≥5 mmHg is associated with hemodynamic outcomes after TEER is unknown.MethodsA total of 164 consecutive patients undergoing TEER at Mayo Clinic between June 2014 and May 2018 were analyzed in this retrospective study. Baseline demographics, as well as clinical, echocardiographic, and procedural data were obtained. Data on direct left atrial pressure (LAP) before and after TEER were recorded. Logistic regression models were constructed to evaluate the association between preprocedure transmitral diastolic mean gradient (pre‐MG) and (1) improvement in LAP following TEER, (2) postprocedure transmitral diastolic mean gradient (post‐MG). A decrease in LAP post TEER was considered an improvement in hemodynamic response. Pre‐MG was categorized as: ≥5 and <5 mmHg.ResultsMedian age of the cohort was 81.5 years (Q1: 76.3, Q3: 87) and 34% were female. At baseline, median transmitral diastolic MG was 4 mmHg (Q1: 3, Q3: 5) and median LAP was 19 mmHg (Q1:16, Q3: 23.5). In a multivariable model, adjusted for age and sex, patients with pre‐MG ≥ 5 mmHg were less likely to see an improvement in LAP post TEER (adjusted odds ratio [aOR]: 0.22, 95% confidence interval [CI]: 0.09, 0.55; p = 0.001) and more likely to have elevated post‐MG (aOR; 7.08, 95% CI: 2.93, 17.13; p < 0.001).ConclusionHigher pre‐MG (≥5 mmHg) was associated with a lower reduction in LAP and higher residual transmitral gradient following TEER suggesting other potential contributors to increased LAP besides mitral regurgitation as a cause of elevated baseline MG.

Background: Left ventricular outflow tract obstruction may occur following transcatheter mitral valve replacement in the setting of mitral annular calcification. Methods: We present a case series whereby preemptive septal radiofrequency ablation (RADIO-TMVR) was used to augment the left ventricular outflow tract for transcatheter mitral valve replacement in 4 patients at risk for left ventricular outflow tract obstruction despite alcohol septal ablation. Results: All patients were female, average age of 74.9 (68.8–80.4) years. Baseline ejection fraction was 71% (63%–75%). Mean mitral valve area was 1.28 (range, 1.0–1.59) cm 2 . Mean mitral valve gradient at rest was 9.5 (range, 7–11) mm Hg. New York Heart Association symptoms were III to IV at baseline. Patients underwent preemptive septal radiofrequency ablation to prevent left ventricular outflow tract obstruction with transcatheter mitral valve replacement a range between 69 and 154 days after alcohol septal ablation. Procedural time was 384 (337–424) minutes with a fluoroscopic time of 31 (14–71) minutes. Radiofrequency ablation time was 132 (100–175) minutes. As anticipated, 3 patients developed complete heart block and underwent pacemaker implantation, whereas 1 had a preexisting pacemaker. One patient developed groin hematoma and heart failure exacerbation. There were no peri-procedural deaths. Preemptive septal radiofrequency ablation to prevent left ventricular outflow tract obstruction with transcatheter mitral valve replacement resulted in septal end-diastolic wall thickness reduction compared with baseline (28.6%, 30.4%, 30.3%, and 11.1%) and following alcohol septal ablation (23.1%, 12%, 8.5%). Valve replacement in the setting of mitral annular calcification was performed in all patients 89 (range, 38–45) days after preemptive septal radiofrequency ablation to prevent left ventricular outflow tract obstruction with transcatheter mitral valve replacement. Two patients had concomitant laceration of the anterior mitral leaflet to further augment the neo-left ventricular outflow tract. Postprocedure, New York Heart Association symptoms improved to class I (3 patients) and class II (1 patient). Conclusions: In at-risk individuals, preemptive septal radiofrequency ablation may be an effective strategy at preventing left ventricular outflow tract obstruction with transcatheter mitral valve replacement.

Abstract Background Pulmonary vein stenosis (PVS), which is often unrecognized, may arise from a variety of conditions resulting in major morbidity and mortality. In some patients, pharmacological therapy may help but more often in advance stages, mechanical treatment must be considered. Transcatheter approaches, both balloon angioplasty (BA) and stent implantation have been applied. While both may be effective, they continue to be limited by restenosis. Herein, we compare the outcomes following BA and stenting for PVS. Purpose PVS presents a challenge for both diagnosis and therapy, with BA and stenting being primarily limited by restenosis. Stenting is performed in most cases and is associated with improved patency rates. Historical comparisons of BA and stenting for PVS have yielded similar results. Our analysis incorporates more conventional studies (2010–2021) and provides a larger stent (N=361) versus BA (N=229) contemporary analysis of the current state of PV intervention practice. Methods From January 1, 2010 to August 2, 2021, studies, limited to English language and humans, were assessed in Ovid MEDLINE®, Ovid Embase, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, and Scopus. Two independent reviewers screened articles including those in which balloon angioplasty or stenting was performed for pulmonary vein stenosis with reporting of restenosis outcomes and data was independently extracted. Systematic review was performed, and overall restenosis rates were reported across all included studies. Meta-analysis was then performed using RevMan 5.4 assessing rates of restenosis and restenosis requiring repeat intervention. Results Our systematic review yielded 34 studies reporting on BA and/or stenting for PVS. Of these, 7 studies (1–7), treating a total of 343 patients with 590 PV interventions (229 BA and 361 Stents) reported restenosis rates with mean follow-up ranging from 10 to 60 months. Stenting was associated with a lower risk of restenosis compared to balloon angioplasty [risk ratio 0.35, 95% CI (0.18, 0.64), p=0.0008] (Figure 1). Restenosis requiring repeat intervention was reported in 5 studies, including 303 patients with 502 PV interventions (160 BA and 342 Stents) with stenting similarly associated with a lower risk of restenosis requiring re-intervention [risk ratio 0.34, 95% CI (0.16, 0.72), p=0.005]. Conclusion Stenting for pulmonary vein stenosis is associated with reduced risk of restenosis and re-intervention as compared to balloon angioplasty. Funding Acknowledgement Type of funding sources: None.

Objective Atrial fibrillation (AF) remains a highly prevalent arrhythmia with significant burden on morbidity and mortality. The impact of AF in the revascularised population remains incompletely described. Given the high prevalence of AF in the revascularised population, we sought to evaluate the incidence and prognosis in patients with pre-existing and new-onset AF following revascularisation. Methods We used the University of Ottawa Heart Institute Revascularisation Registry to identify patients who underwent revascularisation between August 2015 and March 2020, who were prospectively followed for an average of one year. We conducted a retrospective cohort study analysing the association between AF and clinical outcomes. The primary outcome of interest was 1-year major adverse cardiac events (MACE) defined as a composite of death, myocardial infarction, unplanned revascularisation and cerebrovascular accidents. Moreover, secondary outcomes include the individual components of MACE and bleeding. Results A total of 6704 patients underwent revascularisation and completed 1-year clinical follow-up. Median time to follow-up was 12.8 (IQR 11.2–15.9) months. One-year MACE occurred in 166 (21.8%) and 683 (11.5%) patients in AF and non-AF groups, respectively (adjusted HR, 1.61; 95% CI 1.29 to 2.01; p<0.0001). AF was independently predictive of 1-year mortality, myocardial infarction, unplanned revascularisation, cerebrovascular accident and bleeding. Within 1 year, 299 (4.5%) episodes of new-onset AF was observed. New-onset AF following revascularisation was also associated with 1-year MACE, mortality, myocardial infarction, cerebrovascular accident and unplanned revascularisation. Conclusions Preprocedural and new-onset AF following revascularisation remains highly predictive 1-year MACE. AF should be considered in addition to traditional risk factors for adverse outcomes following revascularisation.

Purpose of review Cardiogenic shock with significant mitral regurgitation portends a poor prognosis with limited therapeutic options. Herein, we review the available evidence regarding the patient characteristics, management, impact of transcatheter edge-to-edge repair (TEER) on hemodynamics, and clinical outcomes of patients with cardiogenic shock and mitral regurgitation. Recent findings Several observational studies and systematic reviews have demonstrated the feasibility and safety of TEER in cardiogenic shock complicated by degenerative or functional mitral regurgitation. Surgical interventions for mitral regurgitation remain limited owing to the risk profile of patients in cardiogenic shock. TEER has been studied in both degenerative and functional mitral regurgitation and remains feasible in the critically ill population. Moreover, TEER is associated with reduction in mitral regurgitation and improvement in-hospital and long-term mortality. Summary TEER remains a promising therapeutic option in cardiogenic shock complicated by significant mitral regurgitation, but additional research is required to identify patient and procedural characteristics, hemodynamic parameters, and the optimal time for intervention. Moreover, future randomized controlled trials are in progress to evaluate the potential benefit of TEER against medical management in cardiogenic shock and mitral regurgitation.

AbstractBackgroundMitral transcatheter edge‐to‐edge repair (MTEER) is an established therapeutic approach for mitral regurgitation (MR). Functional mitral regurgitation originating from atrial myopathy (A‐FMR) has been described.ObjectivesWe sought to assess the clinical, echocardiographic and hemodynamic considerations in A‐FMR patients undergoing MTEER.MethodsFrom 2014 to 2020, patients undergoing MTEER for degenerative MR (DMR), functional MR (FMR), and mixed MR were assessed. A‐FMR was defined by the presence of MR > moderate in severity; left ventricular (LV) ejection fraction (LVEF) ≥ 50%; and severe left atrial (LA) enlargement in the absence of LV dysfunction, leaflet pathology, or LV tethering. The diagnosis of A‐FMR (vs. ventricular‐FMR [V‐FMR]) was confirmed by three independent echocardiographers. Baseline characteristics, procedural outcomes as well as clinical and echocardiographic follow‐up are reported. Device success was defined as final MR grade ≤ moderate; MR reduction ≥1 grade; and final transmitral gradient <5 mmHg.Results306 patients underwent MTEER, including DMR (62%), FMR (19%), and mixed MR (19%). FMR cases included 37 (63.8%) V‐FMR and 21 (36.2%) A‐FMR. Tricuspid regurgitation (≥ moderate) was higher in A‐FMR (80.1%) compared to V‐FMR (54%) and DMR (42%). Device success did not significantly differ between A‐FMR and V‐FMR (57% vs. 73%, p = 0.34) or DMR (57% vs. 64%, p = 1.0). The A‐FMR cohort was less likely to achieve ≥3 grades of MR reduction compared to V‐FMR (19% vs. 54%, p = 0.01) and DMR (19% vs. 49.7%, p = 0.01). Patients with V‐FMR and DMR demonstrated significant reductions in mean left atrial pressure (LAP) and peak LA V‐wave, though A‐FMR did not (LAP −0.24 ± 4.9, p = 0.83; peak V‐wave −1.76 ± 9.1, p = 0.39). In follow‐up, echocardiographic and clinical outcomes were similar.ConclusionsIn patients undergoing MTEER, A‐FMR represents one‐third of FMR cases. A‐FMR demonstrates similar procedural success but blunted acute hemodynamic responses compared with DMR and V‐FMR following MTEER. Dedicated studies specifically considering A‐FMR are needed to discern the optimal therapeutic approaches.

Introduction There is emerging evidence supporting the use of the radial artery (RA) as a preferred secondary conduit for coronary artery bypass grafting (CABG) as it is associated with higher rates of graft patency at 5 years when compared with saphenous vein grafts (SVG). The modified Allen’s test (MAT) is traditionally regarded as the standard of care in the assessment of ulnar artery (UA) patency prior to RA harvesting. Unfortunately, due to high false-positive rates, a substantial number of pre-CABG patients are found to have an abnormal MAT despite normal UA patency, resulting in inappropriate exclusion from RA harvesting. The SVG is generally used in its place when this occurs, resulting in potentially lower rates of long-term graft patency. Methods and analysis The CAPITAL iRADIAL-CABG trial is currently enrolling participants 18 years of age or older undergoing CABG for whom the treating physician is considering the use of an RA conduit. Eligible patients will be randomised in a 1:1 fashion to MAT or smartphone-based photoplethysmography application assessment to assess collateral palmar circulation prior to RA harvesting. The primary outcome of the trial is the use of the RA as a conduit during CABG. The primary safety outcome is postoperative palmar ischaemia as determined by clinical assessment or requirement of vascular intervention. Secondary outcomes include vascular complications, early graft failure, need for rescue percutaneous coronary intervention during the index hospitalisation and a composite cardiovascular outcome of myocardial infarction, stroke and cardiovascular death prior to discharge from hospital. A total of 236 participants are planned to be recruited. Ethics and dissemination The study was approved by the Ottawa Heart Science Network Research Ethics Board (approval number 20180865-01H). The study results will be disseminated via conference presentations and peer-reviewed publications. Trial registration number NCT03810729.

AbstractBackgroundThough infrequent, incomplete left atrial appendage closure (LAAC) may result from residual leaks. Percutaneous closure has been described though data is limited.MethodsWe compiled a registry from four centers of patients undergoing percutaneous closure of residual leaks following LAAC via surgical means or with the Watchman device. Leak severity was classified as none (no leak), mild (1–2 mm), moderate (3–4 mm), or severe (≥5 mm). Procedural and clinical success was defined as the elimination of leak or mild residual leak at the conclusion of the procedure or follow‐up, respectively.ResultsOf 72 (age 72.2 ± 9.2 years; 67% male) patients, 53 had undergone prior LAAC using the Watchman device and 19 patients surgical LAAC. Mean CHADS2‐VA2Sc score was 4.0 ± 1.8. The median leak size was 5 mm, range: 2–13). A total of 13 received Amplatzer Vascular Plug‐II, 18 received Amplatzer Duct Occluder‐II and 40 patients received coils. One underwent closure using a 21 mm‐Watchman. Procedural success was 94%. Zero surgical and nine Watchman patients (13%) had a residual leak at procedural‐end (five mild, three moderate, and one severe)—only one patient had no reduction in leak size. Overall leak size reduction was 94%. Two (3%) had intraoperative pericardial effusion. There were no device embolizations, device‐related thrombi, or procedural deaths. Clinical success was maintained at 94%. Two had cerebrovascular accidents—at 2 days (transient ischemic attack) and 10 months postprocedure. Two had major bleeding outside the 30‐day periprocedural window.ConclusionPercutaneous closure of residual leaks following left atrial appendage closure is feasible and associated with good outcomes. The procedural risk appears to be satisfactory.

Abstract Objective We sought to evaluate the association between the institutional volume of catheter‐directed thrombolysis (CDT) for pulmonary embolism and in‐hospital mortality. Background CDT is an increasingly utilized therapy in patients with intermediate/high‐risk PE. However, data on the relationship between hospital volume and clinical outcomes remain limited. Methods Patients who underwent CDT between October 1, 2015, and March 31, 2021, were identified in the Vizient Clinical Database. The primary outcome was in‐hospital mortality. Secondary outcome were major complications, length of stay, and cost. Hospitals were dichotomized into <8 and 8 cases/year following restricted cubic spline analysis. Results A total of 6741 CDT procedures at 171 hospitals were included with a median annual hospital volume of 4.1 cases (IQR = 1.9–8.3). A total of 44 hospitals (25.7%) were classified as high‐volume (8 cases/year) and performed 60.9% of all CDT cases. CDT at high‐volume centers was associated with lower in‐hospital mortality (6.0% vs. 11.3%; p < 0.0001). Stroke and bleeding rates were similar, but pulmonary complications were more frequent at low‐volume centers. CDT at high volume centers was associated with a significantly shorter length of stay and lower cost. The association between high CDT volume and in‐hospital mortality persisted after adjustment for demographics (odds ratio [OR] = 0.49, [0.41–0.58]), demographics and risk factors (OR = 0.52 [0.44–0.62]), and demographics, risk factors, and troponin elevation (OR = 0.51 [0.40–0.66]). Conclusion In a large contemporary cohort of patients undergoing CDT in the United States, low annual institutional volume of CDT was associated with higher in‐hospital mortality.

AbstractBackgroundTranscatheter mitral valve replacement (TMVR) has emerged as a feasible alternative to redo surgical mitral valve replacement (SMVR) in patients with degenerated mitral prostheses, with limited comparative data.MethodsWe compared mid‐term outcomes in patients with degenerated mitral valve prostheses treated with TMVR or redo SMVR. The primary endpoint was survival at 5 years of follow‐up.ResultsFrom 2014 to 2020, 215 patients presented with degenerated mitral valve prostheses. Of whom 86 (40%) were treated with TMVR (75[87%] valve‐in‐valve and 11[13%] valve‐in‐ring), while 129 patients (60%) underwent SMVR. The TMVR cohort was older (p < 0.0001), more symptomatic (p = 0.0003) and had more chronic lung disease (p = 0.02), worse renal function (p = 0.02) and higher right ventricular systolic pressures (p < 0.0001). Thirty‐day mortality was lower with TMVR versus SMVR (2.4% vs. 10.2%, OR4.69 [95% CI 1.25–30.5], p = 0.04) with probability of mortality at 1, 2, and 5 years being 14.7% versus 17.5%, 24.5% versus 20.7%, and 49.9% versus 34.0%, respectively. Mode of prosthesis degeneration, baseline hemodynamics, and valve selection did not appreciably impact outcomes.ConclusionsTMVR for degenerated mitral prostheses is associated with better early survival compared to SMVR despite a greater burden of comorbidities. In contrast, 5 year survival rates appear more favorable with SMVR, which may reflect the lower baseline risk of this population. Clinical, hemodynamic, and echocardiographic follow‐up support the mid‐term durability of TMVR for degenerated mitral prostheses. Further dedicated studies, however, are required to optimize outcomes in this challenging patient cohort and to navigate the choice of approach for each individual patient.