Computational simulation model of transcatheter edge-to-edge mitral valve repair: a proof-of-concept study.

AIMS: As transcatheter mitral valve (MV) interventions are expanding and more device types and sizes become available, a tool supporting operators in pre-procedural planning and the clinical decision-making process is highly desirable. We sought to develop a finite element computational simulation model to predict the results of transcatheter edge-to-edge repair (TEER) interventions. METHODS AND RESULTS: We prospectively enrolled patients with secondary mitral regurgitation (MR) referred for a clinically indicated TEER. The 3D trans-oesophageal echocardiograms performed at the beginning of the procedure were used to perform the simulation. On the 3D dynamic model of the MV that was first obtained, we simulated the clip implantation using the same clip type, size, number, and implantation location that was used during the intervention. The 3D model of the MV obtained after the simulation of the clip implantation was compared with the clinical results obtained at the end of the intervention. We analysed the degree and location of residual MR and the shape and area of the diastolic MV area. We performed computational simulation on five patients. Overall, the simulated models predicted well the degree and location of the residual regurgitant orifice(s) but tended to underestimate the diastolic mitral orifice area. CONCLUSION: In this proof-of-concept study, we present preliminary results on our algorithm simulating clip implantation in five patients with functional MR. We show promising results regarding the feasibility and accuracy in terms of predicting residual MR and the need to improve the estimation of the diastolic MV area.

Cost-effectiveness of population screening for aortic stenosis.

BACKGROUND AND AIMS: Aortic stenosis (AS) is a progressive disease predominantly affecting elderly patients that carries significant morbidity and mortality without aortic valve replacement, the only proven treatment. Our objective was to determine the cost-effectiveness of AS screening using transthoracic echocardiography (TTE) in a geriatric population from the perspective of the publicly funded healthcare system in Canada. METHODS: Markov models estimating the cost-effectiveness ratio (ICER) for AS screening with a one-time TTE were developed. The model included diagnosed and undiagnosed AS health states, hospitalizations, TAVR and post-TAVR health states. Primary analysis included screening at 70 and 80 years of age with intervention at symptom onset, with scenario analysis included for early intervention at the time of severe asymptomatic AS diagnosis. Monte Carlo simulation of 5000 replications was completed with a lifetime horizon and 1.5% discount for costs and outcomes. RESULTS: Screening for AS at the age of 70 years was associated with an ICER of $156,722 and screening at 80 years of age was associated with an ICER of $28,005, suggesting that screening at 80 years of age is cost-effective when willingness-to-pay per QALY is $50,000. Scenario analysis with early intervention was not cost-effective with an ICER of $142,157 at 70 years, and $124,651 at 80 years. CONCLUSION: Screening for AS at 80 years of age with a one-time TTE, in a Canadian population, improves quality of life and is cost-effective in a publicly funded healthcare system providing TAVR is reserved for symptomatic patients.

Left atrial to coronary sinus shunting for treatment of heart failure with mildly reduced or preserved ejection fraction: The ALT FLOW Early Feasibility Study 1-year results.

AIMS: Patients with heart failure and mildly reduced or preserved ejection fraction have limited therapeutic options. The ALT-FLOW Early Feasibility Study evaluated safety, haemodynamics and outcomes for the APTURE transcatheter shunt system, a novel left atrium to coronary sinus shunt in these patients. METHODS AND RESULTS: Safety and shunt implantation success was evaluated for all 116 enrolled patients. An analysis population of implanted patients with a left ventricular ejection fraction (LVEF) >40% (n = 95) was chosen to assess efficacy via paired comparison between baseline and follow-up haemodynamic (3 and 6 months), and echocardiographic, clinical and functional outcomes (6 months and 1 year). Health status and quality of life outcomes were assessed using the Kansas City Cardiomyopathy Questionnaire overall summary score (KCCQ-OSS). The primary safety endpoint, major adverse cardiac, cerebral, and renal events, and reintervention through 30 days, occurred in 3/116 patients (2.6%). All implanted shunts were patent at 1 year. In patients with LVEF >40%, the mean (95% confidence interval) reduction in exercise pulmonary capillary wedge pressure (PCWP) at 20 W was -5.7 (-8.6, -2.9) mmHg at 6 months (p < 0.001). At baseline, 8% had New York Heart Association class I-II status and improved to 68% at 1 year (p < 0.001). KCCQ-OSS at baseline was 39 (35, 43) and improved at 6 months and 1 year by 25 (20-30) and 27 (22-32) points, respectively (both p < 0.0001). No adverse changes in haemodynamic and echocardiographic indices of right heart function were observed at 1 year. Overall, the reduction in PCWP at 20 W and improvement in KCCQ-OSS in multiple subgroups were consistent with those observed for the entire population. CONCLUSIONS: In patients with heart failure and LVEF >40%, the APTURE shunt demonstrated an acceptable safety profile with significant sustained improvements in haemodynamic and patient-centred outcomes, underscoring the need for further evaluation of the APTURE shunt in a randomized trial.

Protein and Exercise to Reverse Frailty in Older Men and Women Undergoing Transcatheter Aortic Valve Replacement: Design of the PERFORM-TAVR Trial.

Despite the high procedural success of transcatheter aortic valve replacement (TAVR), 2 out of 5 older adults report poor physical performance and health-related quality of life (HRQOL) in the ensuing months, particularly those with frailty. There has yet to be a trial examining the synergistic effects of exercise and protein supplementation to counteract frailty and improve patient-centred outcomes following TAVR. The PERFORM-TAVR trial is a multicentre parallel-group randomised clinical trial that is enrolling 200 frail older adults ≥ 70 years of age undergoing TAVR. Patients will be randomly allocated to 1 of 2 treatment groups: standard-of-care lifestyle education (control group) or protein-rich oral nutritional supplement for 4 weeks before TAVR with the addition of home-based supervised exercise sessions for 12 weeks after TAVR (intervention group). The primary outcome will be physical performance as measured by a blinded observer using the Short Physical Performance Battery at 3 months. Secondary outcomes at 3, 6, and 12 months will include HRQOL, as measured by the Short-Form 36 Physical and Mental Component summary scores, and a composite safety end point. The PERFORM-TAVR trial is testing a novel frailty intervention in older adults undergoing TAVR to optimise recovery and downstream HRQOL. This represents a potential paradigm shift that highlights the value of assessing and treating patients' frailty in parallel with their underlying heart valve disease. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03522454.

Dipyridamole and vascular healing following stent implantation.

Introduction: Patients undergoing coronary stent implantation incur a 2% annual rate of adverse events, largely driven by in-stent restenosis (ISR) due to neointimal (NI) tissue proliferation, a process in which smooth muscle cell (SMC) biology may play a central role. Dipyridamole (DP) is an approved therapeutic agent with data supporting improved vascular patency rates. Pre-clinical data supports that DP may enact its vasculoprotective effects via adenosine receptor-A2B (ADOR-A2B). We sought to evaluate the efficacy of DP to mitigate ISR in a pre-clinical rabbit stent model. Methods & Results: 24 New Zealand White Rabbits were divided into two cohorts-non-atherosclerosis and atherosclerosis (n = 12/cohort, 6 male and 6 female). Following stent implantation, rabbits were randomized 1:1 to control or oral dipyridamole therapy for 6 weeks followed by optical coherence tomography (OCT) and histology assessment of NI burden and stent strut healing. Compared to control, DP demonstrated a 16.6% relative reduction in NI volume (14.7 ± 0.8% vs. 12.5 ± 0.4%, p = 0.03) and a 36.2% relative increase in optimally healed stent struts (37.8 ± 2.8% vs. 54.6 ± 2.5%, p < 0.0001). Atherosclerosis demonstrated attenuated effect with no difference in NI burden (15.2 ± 1.0% vs. 16.9 ± 0.8%, p = 0.22) and only a 14.2% relative increase in strut healing (68.3 ± 4.1% vs. 78.7 ± 2.5%, p = 0.02). DP treated rabbits had a 44.6% (p = 0.045) relative reduction in NI SMC content. In vitro assessment of DP and coronary artery SMCs yielded dose-dependent reduction in SMC migration and proliferation. Selective small molecule antagonism of ADOR-A2B abrogated the effects of DP on SMC proliferation. DP modulated SMC phenotypic switching with ADOR-A2B siRNA knockdown supporting its role in the observed effects. Conclusion: Dipyridamole reduces NI proliferation and improves stent healing in a preclinical model of stent implantation with conventional antiplatelets. Atherosclerosis attenuates the observed effect. Clinical trials of DP as an adjunctive agent may be warranted to evaluate for clinical efficacy in stent outcomes.

Efficacy of Milrinone and Dobutamine in Cardiogenic Shock: An Updated Systematic Review and Meta-Analysis.

OBJECTIVES: Inotropic support is commonly used in patients with cardiogenic shock (CS). High-quality data guiding the use of dobutamine or milrinone among this patient population is limited. We compared the efficacy and safety of these two inotropes among patients with low cardiac output states (LCOS) or CS. DATA SOURCES: MEDLINE, Embase, and Cochrane Central Register of Controlled Trials were searched up to February 1, 2023, using key terms and index headings related to LCOS or CS and inotropes. DATA EXTRACTION: Two independent reviewers included studies that compared dobutamine to milrinone on all-cause in-hospital mortality, length of ICU stay, length of hospital stay, and significant arrhythmias in hospitalized patients. DATA SYNTHESIS: A total of eleven studies with 21,084 patients were included in the meta-analysis. Only two randomized controlled trials were identified. The primary outcome, all-cause mortality, favored milrinone in observational studies only (odds ratio [OR] 1.19 (95% CI, 1.02-1.39; p = 0.02). In-hospital length of stay (LOS) was reduced with dobutamine in observational studies only (mean difference -1.85 d; 95% CI -3.62 to -0.09; p = 0.04). There was no difference in the prevalence of significant arrhythmias or in ICU LOS. CONCLUSIONS: Only limited data exists supporting the use of one inotropic agent over another exists. Dobutamine may be associated with a shorter hospital LOS; however, there is also a potential for increased all-cause mortality. Larger randomized studies sufficiently powered to detect a difference in these outcomes are required to confirm these findings.

Evaluation of a Rabbit Model of Vascular Stent Healing: Application of Optical Coherence Tomography.

Percutaneous coronary intervention (PCI) is a management strategy for symptomatic obstructive coronary artery disease (CAD). Despite advancements, in-stent restenosis (ISR) still imparts a 1-2% annual rate of repeat revascularization-a focus of ongoing translational research. Optical coherence tomography (OCT) provides high resolution virtual histology of stents. Our study evaluates the use of OCT for virtual histological assessment of stent healing in a rabbit aorta model, enabling complete assessment of intraluminal healing throughout the stent. ISR varies based on intra-stent location, stent length, and stent type in a rabbit model-important considerations for translational experimental design. Atherosclerosis leads to more prominent ISR proliferation independent of stent-related factors. The rabbit stent model mirrors clinical observations, while OCT-based virtual histology demonstrates utility for pre-clinical stent assessment. Pre-clinical models should incorporate clinical and stent factors as feasible to maximize translation to clinical practice.

Rationale and Design of the Rivaroxaban Post-Transradial Access for the Prevention of Radial Artery Occlusion Trial (CAPITAL-RAPTOR).

INTRODUCTION: Transradial access (TRA) has rapidly emerged as the preferred vascular access site for coronary angiography and percutaneous coronary intervention. Radial artery occlusion (RAO) remains as an important complication of TRA as it precludes future ipsilateral transradial procedures. While intraprocedural anticoagulation has been studied extensively, the definitive role of postprocedural anticoagulation has not yet been established. METHODS AND ANALYSIS: The Rivaroxaban Post-Transradial Access for the Prevention of Radial Artery Occlusion trial is a multicentre, prospective, randomised, open-label, blinded-endpoint design study investigating the efficacy and safety of rivaroxaban to reduce the incidence of RAO. Eligible patients will undergo randomisation to receive either rivaroxaban 15 mg once daily for 7 days or to no additional postprocedural anticoagulation. Doppler ultrasound to assess radial artery patency will be performed at 30 days. ETHICS AND DISSEMINATION: The study protocol has been approved by the Ottawa Health Science Network Research Ethics Board (approval number 20180319-01H). The study results will be disseminated via conference presentations and peer-reviewed publications. TRIAL REGISTRATION NUMBER: NCT03630055.

Inotrope versus placebo therapy in cardiogenic shock: Rationale and study design of the CAPITAL DOREMI2 trial.

BACKGROUND: Cardiogenic shock (CS) is a state of end-organ hypoperfusion related to cardiac dysfunction. Current guidelines recommend consideration of inotrope therapy in patients with CS, however no robust data support their use. The purpose of the CAPITAL DOREMI2 trial is to examine the efficacy and safety of inotrope therapy against placebo in the initial resuscitation of patients with CS. METHODS AND DESIGN: This is a multi-center, double-blind, randomized, placebo-controlled trial comparing single-agent inotrope therapy to placebo in patients with CS. A total of 346 participants with Society for Cardiovascular Angiography and Interventions class C or D CS will be randomized in a 1:1 fashion to inotrope or placebo therapy, which will be administered over a 12-hour period. After this period, participants will continue open-label therapies at the discretion of the treating team. The primary outcome is a composite of all-cause in-hospital death, and, as measured during the 12-hour intervention period, any of: sustained hypotension or high dose vasopressor requirements, lactate greater than 3.5 mmol/L at 6 hours or thereafter, need for mechanical circulatory support, arrhythmia leading to emergent electrical cardioversion, and resuscitated cardiac arrest. All participants will be followed for the duration of their hospitalization, and secondary outcomes will be assessed at the time of discharge. IMPLICATION: This trial will be the first to establish the safety and efficacy of inotrope therapy against placebo in a population of patients with CS and has the potential to alter the standard care provided to this group of patients.

Left Atrial to Coronary Sinus Shunting for Treatment of Symptomatic Heart Failure.

BACKGROUND: Heart failure (HF) is associated with both mortality and a significant decline in health status. Interatrial shunting is increasingly being investigated as a novel therapeutic option. OBJECTIVES: The ALT FLOW Early Feasibility Study was designed to evaluate the safety of the Edwards left atrial to coronary sinus APTURE Transcatheter Shunt System in patients with symptomatic HF. METHODS: A total of 18 centers enrolled patients with symptomatic HF with a pulmonary capillary wedge pressure >15 mm Hg at rest or 25 mm Hg during exercise. RESULTS: Between May 2018 and September 2022, 87 patients underwent attempted APTURE shunt implantation. Mean age was 71 years, and 53% were male. At baseline, mean left ventricular ejection fraction was 59% with 90% of the patients being in NYHA functional class III. Device success was achieved in 78 patients (90%), with no device occlusions or associated adverse events identified after implantation. The primary safety outcome occurred in only 2 patients (2.3%) at 30 days. At 6 months, health status improved: 67% of participants achieved NYHA functional class I to II status, with a 23-point improvement (P < 0.0001; 95% CI: 17-29 points) in the Kansas City Cardiomyopathy Questionnaire overall summary score. Also at 6 months, 20-W exercise pulmonary capillary wedge pressure was 7 mm Hg lower (P < 0.0001; 95% CI: -11 to -4 mm Hg) without change in right atrial pressure or other right heart function indices. CONCLUSIONS: In this single-arm experience, the APTURE Transcatheter Shunt System in patients with symptomatic HF was observed to be safe and resulted in reduction in pulmonary capillary wedge pressure and clinically meaningful improvements in HF symptoms and quality of life indices.

Off-Hours Presentation, Door-to-Balloon Time, and Clinical Outcomes in Patients Referred for Primary Percutaneous Coronary Intervention.

OBJECTIVES: Presentation with ST-segment-elevation myocardial infarction (STEMI) during off-hours may impact timely reperfusion and clinical outcomes. We investigated the association between off-hours presentation, door-to-balloon time, and in-hospital mortality in patients with STEMI referred for primary percutaneous coronary intervention (PCI). METHODS: We included consecutive patients referred for primary PCI at the University of Ottawa Heart Institute between July 2004 and December 2017. The off-hours group included patients presenting on weekends, statutory holidays, or between 18:00 to 07:59 hours on weekdays. The on-hours group included patients presenting between 08:00 and 17:59 hours on weekdays. The primary clinical outcome was the adjusted in-hospital mortality. The primary quality-of-care indicator was door-to-balloon time. RESULTS: A total of 5132 patients were included, with 3152 (61.4%) in the off-hours group and 1980 (38.6%) in the on-hours group. The median door-to-balloon time was longer in the off-hours group compared with the on-hours group (102 minutes vs 77 minutes; P<.001), while the median onset-to-door time was similar (P=.40). There was no difference in the rates of in-hospital mortality (3.5% vs 3.0%; P=.32) or in the adjusted mortality (odds ratio, 1.2; 95% confidence interval, 0.8-1.8; P=.44) between off-hours and on-hours groups. However, door-to-balloon time was an independent predictor of in-hospital mortality (P<.01) and off-hours presentation was an independent predictor of longer door-to-balloon time (P<.001), with an excess of 22.1 minutes. CONCLUSION: Patients treated with primary PCI during off-hours had longer door-to-balloon times. Treatment during off-hours was an independent predictor of longer door-to-balloon time and longer door-to-balloon times were associated with higher mortality.

Association Between the Access Site for Coronary Angiography and Catheter-induced Coronary Artery Dissection.

Background: Catheter-induced coronary artery dissection (CICAD) is a rare complication of coronary angiography. The association between access site and CICAD remains unclear; however, transradial access (TRA) may be associated with a higher incidence of CICAD due to access vessel tortuosity and the mechanical disadvantage of catheters designed for the transfemoral access (TFA) approach. Methods: In this retrospective study, the reports of consecutive left heart catheterizations between April 2007, and December 2021 were reviewed for CICAD. Patients were excluded if the procedural report did not report an arterial access site. Identified CICAD cases were reviewed in detail. Results: There were 142/89,876 (0.16%) identified cases of CICAD. The access site was not associated with an increased risk of CICAD (0.18% with TRA vs 0.15% with TFA; relative risk [RR], 1.18; 95% CI, 0.84-1.65; P = .34) over the entire study period. With respect to TRA-related CICAD, male sex was associated with a decreased risk of dissection (RR, 0.64; 95% CI, 0.41-0.99; P = .04), but ST-elevation myocardial infarction at presentation was associated with an increased risk (RR, 3.01; 95% CI, 1.86-4.85; P < .01). In the TFA-predominant era, TRA was associated with an increased risk of CICAD (0.48% TRA vs 0.11% TFA; RR, 3.42; 95% CI, 2.05-5.69; P < .01)-an association that was not present in the TRA-predominant era. In-hospital mortality in patients with CICAD was 8.5%. Conclusions: CICAD is a rare complication of coronary angiography. Over a 15-year period, we did not demonstrate an association between access site and an increased risk of CICAD. There is substantial mortality associated with CICAD.

Ventricular Rupture at the Site of a Septic Myocardial Abscess After Acute Myocardial Infarction.

Mechanical complications after acute myocardial infarction are well-described yet catastrophic complications of acute coronary syndromes. Uniquely, we describe a rare case of left ventricular free wall rupture at the site of a septic myocardial abscess after an anterior wall myocardial infarction. (Level of Difficulty: Advanced.).

Impact of intracoronary assessments on revascularization decisions: A contemporary evaluation.

OBJECTIVES: To investigate the real-world implementation of intracoronary assessment (ICA) techniques and evaluate their impact on clinical decisions regarding the management of coronary artery disease (CAD) in contemporary practice. BACKGROUND: Coronary angiogram is the gold standard used to diagnose vessel stenosis and guide percutaneous coronary intervention (PCI); however, it is limited by its two-dimensional imaging capabilities. ICA techniques like intravascular ultrasound and optical coherence tomography capture the vessel in three-dimensional images. Comparatively, fractional flow reserve provides information on the physiologic significance of coronary stenosis. Both techniques may improve PCI outcomes if they routinely change physician behavior. METHODS: Patients who underwent ICA between August 2015 and March 2020 were included in the study. The primary outcome was the clinical impact of ICA on physician clinical decision making of a stenotic vessel. The secondary outcome was the clinical changes that occurred following ICA. RESULTS: A total of 1135 patients were included in the study. Physiologic assessment (PA) and image assessment (IA) were performed in 61.4% and 38.6% respectively. Management plans were changed in 38.1% and 23.9% of patients who received PA and IA. Over half of the management change resulted in physicians deciding to not intervene on the stenotic vessel. One-year outcome of these decisions showed no significant increase in major adverse cardiac events (hazard ratio [HR], 0.68; 95% confidence interval [CI], 0.40-1.15; p = 0.15) or unplanned revascularization (HR, 0.78; 95% CI, 0.35-1.74; p = 0.55) suggesting reliance on PA/IA data did not increase risk. CONCLUSION: Selected ICA alters physician management of CAD in one-third of patients being evaluated for revascularization-typically leading to fewer interventions. All cause death is numerally lower in patients that received a change in management. However, the 1-year outcome of these altered decisions does not appear to be significantly different.

Impact of atrial fibrillation on the risk of major adverse cardiac events following coronary revascularisation.

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.

Transcatheter mitral valve repair for inotrope dependent cardiogenic shock - Design and rationale of the CAPITAL MINOS trial.

BACKGROUND: Functional mitral regurgitation (MR) is an important clinical consideration in patients with heart failure. Transcatheter edge-to-edge repair (TEER) has emerged as a useful therapeutic tool for patients with chronic heart failure, however the role of TEER in patients with cardiogenic shock (CS) and MR has not yet been studied in a randomized trial. The Transcatheter Mitral Valve Repair for Inotrope Dependent Cardiogenic Shock (CAPITAL MINOS) trial was therefore designed to determine if TEER improves clinical outcomes in the CS population. METHODS AND DESIGN: The CAPITAL MINOS trial is an open-label, multi-center randomized clinical trial comparing TEER to medical therapy in patients with CS and MR. A total of 144 patients with Society for Cardiovascular Angiography and Interventions (SCAI) class C or D CS and at least 3+ MR will be randomized in a 1:1 ratio to TEER or medical therapy alone. The primary outcome will be a composite of in-hospital all-cause mortality, cardiac transplantation, implantation of durable left ventricular assist device, or discharge on palliative inotropic therapy. Patients will be followed for the duration of their index hospitalization for the primary outcome. Secondary outcomes include 6 month mortality. IMPLICATIONS: The CAPITAL MINOS trial will determine whether TEER improves outcomes in patients with CS and MR and will be an important step in optimizing treatment for this high-risk patient population.