The Use of Decision Modelling to Inform Timely Policy Decisions on Cardiac Resource Capacity During the COVID-19 Pandemic

In Ontario on March 16, 2020, a directive was issued to all acute care hospitals to halt nonessential procedures in anticipation of a potential surge in COVID-19 patients. This included scheduled outpatient cardiac surgical and interventional procedures that required the use of intensive care units, ventilators, and skilled critical care personnel, given that these procedures would draw from the same pool of resources required for critically ill COVID-19 patients. We adapted the COVID-19 Resource Estimator (CORE) decision analytic model by adding a cardiac component to determine the impact of various policy decisions on the incremental waitlist growth and estimated waitlist mortality for 3 key groups of cardiovascular disease patients: coronary artery disease, valvular heart disease, and arrhythmias. We provided predictions based on COVID-19 epidemiology available in real-time, in 3 phases. First, in the initial crisis phase, in a worst case scenario, we showed that the potential number of waitlist related cardiac deaths would be orders of magnitude less than those who would die of COVID-19 if critical cardiac care resources were diverted to the care of COVID-19 patients. Second, with better local epidemiology data, we predicted that across 5 regions of Ontario, there may be insufficient resources to resume all elective outpatient cardiac procedures. Finally in the recovery phase, we showed that the estimated incremental growth in waitlist for all cardiac procedures is likely substantial. These outputs informed timely data-driven decisions during the COVID-19 pandemic regarding the provision of cardiovascular care.

Precautions and Procedures for Coronary and Structural Cardiac Interventions During the COVID-19 Pandemic: Guidance from Canadian Association of Interventional Cardiology

The globe is currently in the midst of a COVID-19 pandemic, resulting in significant morbidity and mortality. This pandemic has placed considerable stress on health care resources and providers. This document from the Canadian Association of Interventional Cardiology- Association Canadienne de Cardiologie d'intervention, specifically addresses the implications for the care of patients in the cardiac catheterization laboratory (CCL) in Canada during the COVID-19 pandemic. The key principles of this document are to maintain essential interventional cardiovascular care while minimizing risks of COVID-19 to patients and staff and maintaining the overall health care resources. As the COVID-19 pandemic evolves, procedures will be increased or reduced based on the current level of restriction to health care services. Although some consistency across the country is desirable, provincial and regional considerations will influence how these recommendations are implemented. We believe the framework and recommendations in this document will provide crucial guidance for clinicians and policy makers on the management of coronary and structural procedures in the CCL as the COVID-19 pandemic escalates and eventually abates.

Remote Ambulatory Cardiac Monitoring Before and After Transcatheter Aortic Valve Replacement

Remote ambulatory cardiac monitoring (rACM) could identify high-grade atrioventricular block (AVB) before and after transcatheter aortic valve replacement (TAVR). Retrospective analysis of patients undergoing TAVR, with 14-day rACM before and after TAVR, was performed. Of 62 patients undergoing TAVR, 41 patients had rACM before TAVR. Three patients had asymptomatic AVB leading to planned pacemaker (PM) implant. After TAVR, 23 patients had rACM, with 1 patient requiring a PM implant for asymptomatic AVB. Five patients underwent unplanned PM after TAVR. Using rACM, almost half of PM implants in TAVR recipients were identified electively. High-grade AVB requiring PM was identified in nearly 10% of patients before TAVR.

Same-Day Discharge After Elective Percutaneous Coronary Interventions in Ontario, Canada

Background

To manage overcrowding and bed shortages in Canadian hospitals, same‐day discharge (SDD) after percutaneous coronary intervention (PCI) has emerged as a solution to improve resource utilization. However, limited information exists regarding current trends, hospital variation, and safety of SDD PCI in Canada.

Methods and Results

We evaluated outpatients undergoing elective PCI in Ontario, Canada, from October 2008 to March 2016. SDD was defined when patients were discharged on the day of PCI, and non‐SDD was defined as those patients who had 1 overnight stay. The primary outcome was 30‐day all‐cause death or hospitalization for acute coronary syndrome. Inverse probability of treatment weighting with propensity score was used to account for differences in baseline and clinical characteristics between SDD and non‐SDD groups. Among 35 972 patients who underwent elective PCI at 17 PCI centers in Ontario, 10 801 patients (30%) had SDD PCI and 25 121 patients (70%) had non‐SDD PCI. Substantial hospital variation for SDD PCI was observed, ranging from 0% to 87% during the study period. In the propensity‐weighted cohort, SDD patients had no significant difference in 30‐day rates of death or hospitalization for acute coronary syndrome (1.3% versus 1.6%; hazard ratio: 0.84 [95% CI, 0.65–1.08]; P=0.17) compared with non‐SDD patients. SDD and non‐SDD patients also had no significant difference in 30‐day rates of mortality or coronary revascularization.

Conclusions

In this large population‐based cohort of elective PCI patients, we demonstrated the safety of SDD PCI. Increased adoption of this strategy could lead to improved bed‐flow efficiency and substantial savings for the Canadian healthcare system without comprising outcomes.

See Editorial Patel and Banerjee

Factors associated with door-in to door-out delays among ST-segment elevation myocardial infarction (STEMI) patients transferred for primary percutaneous coronary intervention: a population-based cohort study in Ontario, Canada

BACKGROUND

Compared to ST-segment elevation myocardial infarction (STEMI) patients who present at centres with catheterization facilities, those transferred for primary percutaneous coronary intervention (PCI) have substantially longer door-in to door-out (DIDO) times, where DIDO is defined as the time interval from arrival at a non-PCI hospital, to transfer to a PCI hospital. We aimed to identify potentially modifiable factors to improve DIDO times in Ontario, Canada and to assess the impact of DIDO times on 30-day mortality.

METHODS

A population-based, retrospective cohort study of 966 STEMI patients transferred for primary PCI in Ontario in 2012 was conducted. Baseline factors were examined across timely DIDO status. Multivariate logistic regression was used to examine independent predictors of timely DIDO as well as the association between DIDO times and 30-day mortality.

RESULTS

The median DIDO time was 55 min, with 20.1% of patients achieving the recommended DIDO benchmark of ≤30 min. Age (OR> 75 vs 18-55 0.30, 95% CI: 0.16-0.56), symptom-to-first medical contact (FMC) time (OR61-120mins vs < 60mins 0.60, 95% CI: 0.39-0.90; OR>120mins vs < 60mins 0.53, 95% CI:0.35-0.81) and emergency medical services transport with a pre-hospital electrocardiogram (ECG) (OREMS transport + ECG vs self-transport 2.63, 95% CI:1.59-4.35) were the strongest predictors of timely DIDO. Patients with timely ECG were more likely to have recommended DIDO times (33.0% vs 12.3%; P < 0.001). A significantly higher proportion of those who met the DIDO benchmark had timely FMC-to-balloon times (78.7% vs 27.4%; P < 0.001). Compared to patients with DIDO time ≤ 30 min, those with DIDO times > 90 min had significantly higher adjusted 30-day mortality rates (OR 2.82, 95% CI:1.10-7.19).

CONCLUSIONS

While benchmark DIDO times were still rarely achieved in the province, we identified several potentially modifiable factors in the STEMI system that might be targeted to improve DIDO times. Our findings that patients who received a pre-hospital ECG were still being transferred to non-PCI capable centres suggest strategies addressing this gap may improve patient outcomes.

Evolution of Procedural and Clinical Outcomes After Balloon-Expanding Transcatheter Aortic Valve Implantation In Canada (from the Early Canadian Experience and SOURCE XT Registries)

Transcatheter aortic valve implantation (TAVI) has evolved globally, yet its evolution and performance across the Canadian landscape have yet to be formally assessed. Patients captured within the early Canadian TAVI experience with a balloon-expanding valve (n = 339; 2005 to 2009) and those enrolled in the Canadian SOURCE XT registry (n = 415; 2012 to 2015) were systematically compared with respect to baseline clinical, echocardiographic, and procedural characteristics. Valve-related and clinical outcomes were compared across the 2 time periods according to standardized definitions. Notable baseline between-group differences were noted across time, with Society of Thoracic Surgeons Predicted Risk of Mortality score being lower in the SOURCE XT cohort compared with the earlier Canadian cohort (7.4 ± 6.6% vs 9.8 ± 6.4%, p <0.001). The SOURCE XT cohort underwent TAVI through the transfemoral approach more frequently than their earlier Canadian counterparts (75% vs 48%), at the expense of transapical access, with major access site vascular complications (2.7% vs 13%), and ≥mild residual aortic regurgitation (39% vs 69%) being significantly less frequent (p <0.001 for all). At 30-days, there were no significant differences in rates of stroke (1.9% vs 2.4%) or new pacemakers (5.8% vs 5.0%); however, 30-day and 1-year mortality rates were significantly lower in the SOURCE XT cohort (3.6% vs 10.4%; 13.0% vs 24.2%, respectively, p<0.001 for both). In conclusion, TAVIs evolution in Canada with a balloon-expanding valve coincided with more optimized patient selection and increasing use of transfemoral access, which along with increasing operator experience, contributed to improved procedural and longer term clinical outcomes.

Barriers to the use of emergency medical services for ST-elevation myocardial infarction: Determining why many patients opt for self-transport

RATIONALE, AIMS, AND OBJECTIVES

Access to timely ST-elevation myocardial infarction (STEMI) care is facilitated by paramedics and emergency medical services (EMS). However, a large proportion of STEMI patients do not access care through EMS. This study sought to identify patient-reported factors for their decision to use (or not use) EMS.

METHODS

Semi-structured interviews were conducted with a sample of STEMI patients admitted to a large tertiary care centre between November 2011 and January 2012. Participants were grouped according to mode of transportation to hospital at time of index event (EMS vs self-transport). Participant responses were classified using a published framework (modified for a STEMI population) as barriers or facilitators to EMS use, and compared between groups.

RESULTS

Data were collected on 61 patients (32 EMS, 29 self-transport). Mean age was 60.3 (SD 11.5), and 23% were female. EMS users were more likely to have a Killip Class >1 (25% vs 4%; P = 0.03). Self-transport patients were more likely to perceive EMS as slower (48% vs 0%) and express concerns over resources misuse (34% vs 3%; P = 0.002), when compared to EMS patients. Patients who accessed EMS were more likely to acknowledge the benefits of EMS (44% vs 7%; P = 0.001) and were more likely to have been encouraged by a family member to call EMS (34% vs 4%; P = 0.003).

CONCLUSIONS

STEMI patient perceptions are a key factor in determining EMS use. Health care stakeholders should target the identified barriers to improve utilization of EMS, and develop strategies to optimize care for patients who do not access EMS.

Does Early Coronary Angiography Improve Survival After out-of-Hospital Cardiac Arrest? A Systematic Review With Meta-Analysis

BACKGROUND

In patients with out-of-hospital cardiac arrest who achieve return of spontaneous circulation, coronary angiography (CAG) might improve outcomes. We conducted a systematic review and meta-analysis to elucidate the benefit and optimal timing of early CAG in comatose out-of-hospital cardiac arrest patients with return of spontaneous circulation.

METHODS

We searched MEDLINE, EMBASE, and Cochrane from 1990 to May 2017. Studies reporting survival and/or neurological survival in early (< 24-hour) vs late/no CAG were selected. We used the Clinical Advances Through Research and Information Translation (CLARITY) risk of bias in cohort studies tool and Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) criteria to assess risk of bias and quality of evidence, respectively. Results were pooled using random effects and presented as risk ratios (RRs) with 95% confidence intervals (CIs).

RESULTS

After screening 9185 titles/abstracts and 631 full-text articles, we included 23 nonrandomized studies. Short (to discharge or 30 days) and long-term (1-5 years) survival were significantly improved (52% and 56%, respectively) in the early < 24-hour CAG group compared with the late/no CAG group (RR, 1.52; 95% CI, 1.32-1.74; P < 0.00001; I2, 94% and RR, 1.56; 95% CI, 1.14-2.14; P = 0.006; I2, 86%). Survival with good neurological outcome was also improved by 69% in the < 24-hour CAG group at short- (RR, 1.69; 95% CI, 1.40-2.04; P < 0.00001; I2, 93%) and intermediate-term (3-11 months; RR, 1.49; 95% CI, 1.27-1.76; P < 0.00001; I2, 67%). We found consistent benefits in the < 2-hour and < 6-hour subgroups. Early CAG was associated with significantly better outcomes in studies of patients without ST-elevation, but the results did not reach statistical significance in studies of patients with ST-elevation.

CONCLUSIONS

On the basis of very low quality, but consistent evidence, early CAG (< 24 hours) was associated with significantly higher survival and better neurologic outcomes.

Polygenic Contribution in Individuals With Early-Onset Coronary Artery Disease

BACKGROUND

Despite evidence of high heritability, monogenic disorders are identified in a minor fraction of individuals with early-onset coronary artery disease (EOCAD). We hypothesized that some individuals with EOCAD carry a high number of common genetic risk variants, with a combined effect similar to Mendelian forms of coronary artery disease, such as familial hypercholesterolemia.

METHODS AND RESULTS

To confirm the polygenic contribution to EOCAD (age of ≤40 years for men and ≤45 years for women), we calculated in 111 418 British participants from the UK Biobank cohort a genetic risk score (GRS) based on the presence of 182 independent variants associated with coronary artery disease (GRS182). Participants with a diagnosis of EOCAD who underwent a revascularization procedure (n=96) had a significantly higher GRS182 (P=3.21×10^-9) than those without EOCAD. An increase of 1 SD in GRS182 corresponded to an odds ratio of 1.84 (1.52-2.24) for EOCAD. The prevalence of a polygenic contribution that increased EOCAD risk similar to what is observed in heterozygous familial hypercholesterolemia was estimated at 1 in 53. In a local cohort of individuals with EOCAD (n=30), GRS182 was significantly increased compared with UK Biobank controls (P=0.001). Seven participants (23%) had a GRS182 corresponding to an estimated 2-fold increase in EOCAD risk; none had a rare mutation involved in monogenic dyslipidemia or EOCAD.

CONCLUSIONS

These results suggest a significant polygenic contribution in individuals presenting with EOCAD, which could be more prevalent than familial hypercholesterolemia. Determination of the polygenic risk component could be included in the diagnostic workup of patients with EOCAD.

Avoiding S3 Valve Over-Sizing by Deployment Balloon Over-Filling: Impact on Rates of Permanent Pacemaker and Other Procedural Complications During TAVR

OBJECTIVES

Patients with annular areas just above nominal S3 valve areas are at increased risk of over-sizing if a larger valve is implanted. We therefore evaluated the rate of permanent pacemaker (PPM) implantation associated with avoiding over-sizing by selective deployment balloon over-filling during transcatheter aortic valve replacement (TAVR) with the Sapien 3 (S3) valve.

METHODS

We included consecutive patients treated with the S3 valve from January 2016 to May 2017. We identified computed tomography annular areas where the nominally deployed valve would be over-sized by >12%-15% (areas 340-360 mm² for 23 mm valve, 420-450 mm² for 26 mm valve, 530-580 mm² for 29 mm valve) as those at highest risk for valve over-sizing. In these situations, we used the smaller valve and over-filled the deployment balloon to achieve a predicted valve area/annular area ratio of approximately 1. For annular areas >650 mm², we over-filled the 29 mm valve to achieve a similar ratio.

RESULTS

We evaluated 102 patients (59 males; mean age, 83.7 ± 6.5 years; mean STS score, 10.2). Over-filling of the deployment balloon was used in 35 cases (34%). We observed a post-TAVR PPM rate of 6.9% overall and 2.7% among the 75 patients without pre-TAVR right bundle-branch block (RBBB). Cases with valve over-filling vs nominal deployment had infrequent need for postdilation (14.3% vs 6.0%, respectively; P=.17) and similar postprocedure gradients (9.9 mm Hg vs 10.3 mm Hg, respectively; P=.59).

CONCLUSION

A strategy to avoid S3 valve over-sizing by selective deployment balloon over-filling was associated with a low rate of PPM, especially in patients without pre-existing RBBB.

Double-Dose Versus Standard-Dose Clopidogrel According to Smoking Status Among Patients With Acute Coronary Syndromes Undergoing Percutaneous Coronary Intervention

Background

Prior Studies have suggested better outcomes in smokers compared with nonsmokers receiving clopidogrel (“smoker's paradox”). The impact of a more intensive clopidogrel regimen on ischemic and bleeding risks in smokers with acute coronary syndromes requiring percutaneous coronary interventions remains unclear.

Methods and Results

We analyzed 17 263 acute coronary syndrome patients undergoing percutaneous coronary intervention from the CURRENT‐OASIS 7 (Clopidogrel and Aspirin Optimal Dose Usage to Reduce Recurrent Events—Seventh Organization to Assess Strategies in Ischemic Symptoms) trial, which compared double‐dose (600 mg day 1;150 mg days 2–7; then 75 mg daily) versus standard‐dose (300 mg day 1; then 75 mg daily) clopidogrel in acute coronary syndrome patients. The primary outcome was cardiovascular death, myocardial infarction, or stroke at 30 days. Interactions between treatment allocation and smoking status (current smokers versus nonsmokers) were evaluated. Overall, 6394 patients (37.0%) were current smokers. For the comparison of double‐ versus standard‐dose clopidogrel, there were significant interactions in smokers and nonsmokers for the primary outcome (P=0.031) and major bleeding (P=0.002). Double‐ versus standard‐dose clopidogrel reduced the primary outcome among smokers by 34% (hazard ratio [HR] 0.66, 95% confidence interval [CI], 0.50–0.87, P=0.003), whereas in nonsmokers, there was no apparent benefit (HR 0.96, 95% CI, 0.80–1.14, P=0.61). For major bleeding, there was no difference between the groups in smokers (HR 0.77, 95% CI, 0.48–1.24, P=0.28), whereas in nonsmokers, the double‐dose clopidogrel regimen increased bleeding (HR 1.89, 95% CI, 1.37–2.60, P<0.0001). Double‐dose clopidogrel reduced the incidence of definite stent thrombosis in smokers (HR 0.41, 95% CI, 0.24–0.71) and nonsmokers (HR 0.63, 95% CI, 0.42–0.93; P for interaction=0.19).

Conclusions

In smokers, a double‐dose clopidogrel regimen reduced major cardiovascular events and stent thrombosis after percutaneous coronary intervention, with no increase in major bleeding. This suggests that clopidogrel dosing in patients with acute coronary syndromes should be personalized, taking into consideration both ischemic and bleeding risk.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00335452.

Comparison of Outcomes of Balloon-Expandable Versus Self-Expandable Transcatheter Heart Valves for Severe Aortic Stenosis

Transcatheter aortic valve implantation (TAVI) is the treatment of choice for inoperable and high-risk patients with severe aortic stenosis. Our objectives were to elucidate potential differences in clinical outcomes and safety between balloon-expandable versus self-expandable transcatheter heart valves (THV). We performed a retrospective cohort study of all transfemoral TAVI procedures in Ontario, Canada, from 2007 to 2013. Patients were categorized into either balloon-expandable or self-expandable THV groups. The primary outcomes were 30-day and 1-year death, with secondary outcomes of all-cause readmission. Safety outcomes included bleeding, permanent pacemaker implantation, need for a second THV device, postprocedural paravalvular aortic regurgitation, stroke, vascular access complication, and intensive care unit length of stay. Inverse probability of treatment-weighted regression analyses using a propensity score were used to account for differences in baseline confounders. Our cohort consisted of 714 patients, of whom 397 received a self-expandable THV, whereas 317 had a balloon-expandable THV system. There were no differences in death or all-cause readmission. In terms of safety, the self-expandable group was associated with significantly higher rates of inhospital stroke (p value <0.05), need for a second THV device (5.3% vs 2.7%; p value = 0.013), and permanent pacemaker (22.6% vs 8.9%; p value <0.001), whereas the balloon-expandable group had more vascular access site complications (23.1% vs 16.7%; p value = 0.002). Thus, we found similar clinical outcomes of death or readmission for patients who underwent transfemoral TAVI with either balloon-expandable or self-expandable THV systems. However, there were important differences in their safety profiles.

Negotiating Tensions Between Theory and Design in the Development of Mailings for People Recovering From Acute Coronary Syndrome

Background

Taking all recommended secondary prevention cardiac medications and fully participating in a formal cardiac rehabilitation program significantly reduces mortality and morbidity in the year following a heart attack. However, many people who have had a heart attack stop taking some or all of their recommended medications prematurely and many do not complete a formal cardiac rehabilitation program.

Objective

The objective of our study was to develop a user-centered, theory-based, scalable intervention of printed educational materials to encourage and support people who have had a heart attack to use recommended secondary prevention cardiac treatments.

Methods

Prior to the design process, we conducted theory-based interviews and surveys with patients who had had a heart attack to identify key determinants of secondary prevention behaviors. Our interdisciplinary research team then partnered with a patient advisor and design firm to undertake an iterative, theory-informed, user-centered design process to operationalize techniques to address these determinants. User-centered design requires considering users’ needs, goals, strengths, limitations, context, and intuitive processes; designing prototypes adapted to users accordingly; observing how potential users respond to the prototype; and using those data to refine the design. To accomplish these tasks, we conducted user research to develop personas (archetypes of potential users), developed a preliminary prototype using behavior change theory to map behavior change techniques to identified determinants of medication adherence, and conducted 2 design cycles, testing materials via think-aloud and semistructured interviews with a total of 11 users (10 patients who had experienced a heart attack and 1 caregiver). We recruited participants at a single cardiac clinic using purposive sampling informed by our personas. We recorded sessions with users and extracted key themes from transcripts. We held interdisciplinary team discussions to interpret findings in the context of relevant theory-based evidence and iteratively adapted the intervention accordingly.

Results

Through our iterative development and testing, we identified 3 key tensions: (1) evidence from theory-based studies versus users’ feelings, (2) informative versus persuasive communication, and (3) logistical constraints for the intervention versus users’ desires or preferences. We addressed these by (1) identifying root causes for users’ feelings and addressing those to better incorporate theory- and evidence-based features, (2) accepting that our intervention was ethically justified in being persuasive, and (3) making changes to the intervention where possible, such as attempting to match imagery in the materials to patients’ self-images.

Conclusions

Theory-informed interventions must be operationalized in ways that fit with user needs. Tensions between users’ desires or preferences and health care system goals and constraints must be identified and addressed to the greatest extent possible. A cluster randomized controlled trial of the final intervention is currently underway.

Identifying determinants of medication adherence following myocardial infarction using the Theoretical Domains Framework and the Health Action Process Approach

BACKGROUND

Despite evidence-based recommendations, adherence with secondary prevention medications post-myocardial infarction (MI) remains low. Taking medication requires behaviour change, and using behavioural theories to identify what factors determine adherence could help to develop novel adherence interventions.

OBJECTIVE

Compare the utility of different behaviour theory-based approaches for identifying modifiable determinants of medication adherence post-MI that could be targeted by interventions.

METHODS

Two studies were conducted with patients 0-2, 3-12, 13-24 or 25-36 weeks post-MI. Study 1: 24 patients were interviewed about barriers and facilitators to medication adherence. Interviews were conducted and coded using the Theoretical Domains Framework. Study 2: 201 patients answered a telephone questionnaire assessing Health Action Process Approach constructs to predict intention and medication adherence (MMAS-8).

RESULTS

Study 1: domains identified: Beliefs about Consequences, Memory/Attention/Decision Processes, Behavioural Regulation, Social Influences and Social Identity. Study 2: 64, 59, 42 and 58% reported high adherence at 0-2, 3-12, 13-24 and 25-36 weeks. Social Support and Action Planning predicted adherence at all time points, though the relationship between Action Planning and adherence decreased over time.

CONCLUSIONS

Using two behaviour theory-based approaches provided complimentary findings and identified modifiable factors that could be targeted to help translate Intention into action to improve medication adherence post-MI.

Optical Coherence Tomography-Guided Percutaneous Coronary Intervention in ST-Segment-Elevation Myocardial Infarction: A Prospective Propensity-Matched Cohort of the Thrombectomy Versus Percutaneous Coronary Intervention Alone Trial

BACKGROUND

Patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment-elevation myocardial infarction are at increased risk for adverse events. It is unclear if image guidance by optical coherence tomography (OCT) can improve outcomes in these patients. We compared OCT-guided versus angiography-guided primary PCI for ST-segment-elevation myocardial infarction among patients in the Thrombectomy Versus PCI Alone (TOTAL) trial.

METHODS AND RESULTS

Among 10 732 patients enrolled in the TOTAL trial, OCT was used for PCI guidance as a part of a prospective substudy in 214 patients. Using 2:1 propensity matching, we identified 428 patients in the trial who had PCI performed with angiography guidance alone. The primary outcome was a composite of cardiovascular death, myocardial infarction, stent thrombosis, and target-vessel revascularization at 1 year. Secondary outcomes included final in-stent angiographic minimum lumen diameter, procedure time, and contrast dose. The final in-stent angiographic minimum lumen diameter was 2.99±0.48 mm in the OCT-guided group versus 2.79±0.47 mm in the angiography-guided group (P<0.0001). OCT- and angiography-guided PCI had a median (interquartile range) procedure time of 58 (47, 71) minute versus 38 (28, 52) minute (P<0.0001) and total contrast dose of 239.7±81.1 mL versus 193.3±78.6 mL (P<0.0001). The primary outcome was observed in 7.5% of the OCT-guided group versus 9.8% of the angiography-guided group (hazard ratio, 0.76; 95% confidence interval, 0.43-1.34; P=0.34).

CONCLUSIONS

OCT-guided primary PCI for ST-segment-elevation myocardial infarction was associated with a larger final in-stent minimum lumen diameter. There was no significant difference in clinical outcomes at 1 year; however, the study was underpowered to detect a treatment effect.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01149044.

Impact of Center Experience on Patient Radiation Exposure During Transradial Coronary Angiography and Percutaneous Intervention: A Patient-Level, International, Collaborative, Multi-Center Analysis

Background

The adoption of the transradial (TR) approach over the traditional transfemoral (TF) approach has been hampered by concerns of increased radiation exposure—a subject of considerable debate within the field. We performed a patient‐level, multi‐center analysis to definitively address the impact of TR access on radiation exposure.

Methods and Results

Overall, 10 centers were included from 6 countries—Canada (2 centers), United Kingdom (2), Germany (2), Sweden (2), Hungary (1), and The Netherlands (1). We compared the radiation exposure of TR versus TF access using measured dose‐area product (DAP). To account for local variations in equipment and exposure, standardized TR:TF DAP ratios were constructed per center with procedures separated by coronary angiography (CA) and percutaneous coronary intervention (PCI). Among 57 326 procedures, we demonstrated increased radiation exposure with the TR versus TF approach, particularly in the CA cohort across all centers (weighted‐average ratios: CA, 1.15; PCI, 1.05). However, this was mitigated by increasing TR experience in the PCI cohort across all centers (r=−0.8; P=0.005). Over time, as a center transitioned to increasing TR experience (r=0.9; P=0.001), a concomitant decrease in radiation exposure occurred (r=−0.8; P=0.006). Ultimately, when a center's balance of TR to TF procedures approaches 50%, the resultant radiation exposure was equivalent.

Conclusions

The TR approach is associated with a modest increase in patient radiation exposure. However, this increase is eliminated when the TR and TF approaches are used with equal frequency—a guiding principle for centers adopting the TR approach.

Reperfusion Times for Radial Versus Femoral Access in Patients With ST-Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention: Observations From the Cardiac Care Network Provincial Primary PCI Registry

BACKGROUND

Radial access is associated with less bleeding and vascular complications. However, it may delay reperfusion during primary percutaneous coronary intervention for ST-segment-elevation myocardial infarction.

METHODS AND RESULTS

A provincial database prospectively collected clinical and procedural characteristics for all urgent percutaneous coronary intervention procedures performed between June 2010 and September 2011 in Ontario for ST-segment-elevation myocardial infarction, including time of arrival in the catheterization laboratory and time of first balloon inflation. After excluding patients with cardiogenic shock, with previous bypass surgery, or who received fibrinolysis, 2947 patients were included in the analysis. Propensity score matching was used to minimize difference in clinical characteristics between radial and femoral access procedures. Predictors of radial access included younger age and male sex. After propensity score matching, the median time from arrival in the cardiac catheterization laboratory to first balloon was 27 minutes (25th%-75th%, 21-34) for the femoral group and 30 minutes (25th%-75th %, 24-39) for the radial group (P<0.001). When hospitals were stratified based on the proportion of primary percutaneous coronary intervention cases that were performed using radial access, there was no difference in treatment times between radial and femoral access in the tercile of hospitals that used radial access most frequently. There were no significant differences in the rates of death or myocardial infarction at 30 days.

CONCLUSIONS

This contemporary multicenter registry demonstrates that the time to first balloon inflation is slightly longer with radial access than with femoral access, although the 3 minute difference is unlikely to be clinically relevant. There is no difference in treatment times at hospitals that frequently use radial access for primary percutaneous coronary intervention. Short-term mortality and reinfarction rates are similar with radial and femoral access.

Outcomes after thrombus aspiration for ST elevation myocardial infarction: 1-year follow-up of the prospective randomised TOTAL trial

BACKGROUND

Two large trials have reported contradictory results at 1 year after thrombus aspiration in ST elevation myocardial infarction (STEMI). In a 1-year follow-up of the largest randomised trial of thrombus aspiration, we aimed to clarify the longer-term benefits, to help guide clinical practice.

METHODS

The trial of routine aspiration ThrOmbecTomy with PCI versus PCI ALone in Patients with STEMI (TOTAL) was a prospective, randomised, investigator-initiated trial of routine manual thrombectomy versus percutaneous coronary intervention (PCI) alone in 10,732 patients with STEMI. Eligible adult patients (aged ≥18 years) from 87 hospitals in 20 countries were enrolled and randomly assigned (1:1) within 12 h of symptom onset to receive routine manual thrombectomy with PCI or PCI alone. Permuted block randomisation (with variable block size) was done by a 24 h computerised central system, and was stratified by centre. Participants and investigators were not masked to treatment assignment. The trial did not show a difference at 180 days in the primary outcome of cardiovascular death, myocardial infarction, cardiogenic shock, or heart failure. However, the results showed improvements in the surrogate outcomes of ST segment resolution and distal embolisation, but whether or not this finding would translate into a longer term benefit remained unclear. In this longer-term follow-up of the TOTAL study, we report the results on the primary outcome (cardiovascular death, myocardial infarction, cardiogenic shock, or heart failure) and secondary outcomes at 1 year. Analyses of the primary outcome were by modified intention to treat and only included patients who underwent index PCI. This trial is registered with ClinicalTrials.gov, number NCT01149044.

FINDINGS

Between Aug 5, 2010, and July 25, 2014, 10,732 eligible patients were enrolled and randomly assigned to thrombectomy followed by PCI (n=5372) or to PCI alone (n=5360). After exclusions of patients who did not undergo PCI in each group (337 in the PCI and thrombectomy group and 331 in the PCI alone group), the final study population comprised 10,064 patients (5035 thrombectomy and 5029 PCI alone). The primary outcome at 1 year occurred in 395 (8%) of 5035 patients in the thrombectomy group compared with 394 (8%) of 5029 in the PCI alone group (hazard ratio [HR] 1·00 [95% CI 0·87-1·15], p=0·99). Cardiovascular death within 1 year occurred in 179 (4%) of the thrombectomy group and in 192 (4%) of 5029 in the PCI alone group (HR 0·93 [95% CI 0·76-1·14], p=0·48). The key safety outcome, stroke within 1 year, occurred in 60 patients (1·2%) in the thrombectomy group compared with 36 (0·7%) in the PCI alone group (HR 1·66 [95% CI 1·10-2·51], p=0·015).

INTERPRETATION

Routine thrombus aspiration during PCI for STEMI did not reduce longer-term clinical outcomes and might be associated with an increase in stroke. As a result, thrombus aspiration can no longer be recommended as a routine strategy in STEMI.

FUNDING

Canadian Institutes of Health Research, Canadian Network and Centre for Trials Internationally, and Medtronic Inc.

Medical Therapy and Coronary Revascularization for Patients With Stable Coronary Artery Disease and Unclassified Appropriateness Score

Although the appropriate use criteria incorporate common clinical scenarios for coronary revascularization, a significant proportion of patients with stable coronary artery disease (CAD) cannot be assigned an appropriateness score. Our objective was to characterize these patients and to evaluate whether coronary revascularization is associated with improved outcomes. A population-based cohort of patients aged ≥66 years, who underwent cardiac catheterization in Ontario, Canada, were included. Clinical characteristics were compared between patients with and without an appropriateness score. Clinical outcomes between coronary revascularization and medical therapy in patients with unclassified appropriateness score were compared using the inverse probability of treatment-weighted propensity method for confounder adjustment. Of the 19,228 patients with stable CAD, 11.2% (2,153 patients) were not assigned to an appropriateness score, mostly (92.9%) because of a lack of ischemic evaluation or a noninterpretable test. These patients were older, had higher rate of severe angina, and had more medical co-morbidities compared to patients with an appropriateness score. The 2-year rate of death or myocardial infarction in patients with unclassified appropriateness score was 15.3% in the revascularization group versus 20.7% in the medical therapy group. After propensity weighting, revascularization was associated with significantly lower hazard ratio (0.70; 95% confidence interval 0.61 to 0.79) for death or myocardial infarction compared with medical therapy. In conclusion, in patients aged ≥66 years with stable CAD and unclassified appropriateness score, revascularization is associated with improved outcomes.