Clinical Practice Variations in the Management of Stress-Induced Cardiomyopathy: A Canadian Perspective.

Despite increased recognition of stress-induced cardiomyopathy (SIC), there are no randomized controlled trials or established guidelines to direct therapeutic strategies and little is known about the local experience in Canada. The objective of this study was to better understand the clinical practice variations in the management of SIC across Canada. By using an online platform, a series of questions were distributed to practicing cardiologists between October and November 2018. In total, 172 cardiologists completed the survey. Although many cardiologists have managed patients with SIC, more than two-thirds do not adhere to any guidelines or references. Of those who do, the top referenced resources included expert consensus statements from the American College of Cardiology, the European Society of Cardiology, general heart failure guidelines, and UpToDate. Regarding investigations, most participants routinely order TTEs and coronary angiograms, and a minority would order pheochromocytoma workup. Common medications prescribed for hemodynamically stable patients include ß-blockers, angiotensin-converting enzyme inhibitors, antiplatelet agents, and anticoagulation. Some 3% of participants reported not prescribing any cardiac medications. Most respondents follow up with patients with SIC within a 3-month period. The risk factors most believed to be associated with SIC included female gender, anxiety, older age, ethnicity, and diabetes. No participants believed that male gender was a risk factor. Many participants believed there needs to be improvements made, such as a Canadian guideline, a Canadian registry, or dedicated workshops at the national cardiology conference. This study demonstrates ongoing variability in the clinical management of SIC across Canada and illustrates a potential area for further research.

Autologous Bone Marrow Stem Cell Therapy in Patients With ST-Elevation Myocardial Infarction: A Systematic Review and Meta-analysis.

BACKGROUND: Randomized controlled trials (RCTs) on bone marrow stem cell (BMSC) therapy in ST-elevation myocardial infarction (STEMI) patients have reported conflicting results. Our main objective was to critically appraise and meta-analyze best-available evidence on efficacy and safety of intracoronary administration of autologous BMSC therapy in STEMI patients after primary percutaneous coronary intervention. METHODS: We conducted a search of MEDLINE, PubMed, EMBASE, CENTRAL, Global Health, CINAHL, and conference proceedings in February 2017. Our primary outcome was all-cause mortality. Secondary and safety outcomes included cardiac death, heart failure, arrhythmias, repeat myocardial infarction, or target vessel revascularizations; or improved health-related quality of life, left ventricular ejection fraction, or infarct size. Summary relative and absolute risks were obtained using random effects models. We also evaluated the strength of evidence. RESULTS: A comprehensive database search identified 42 RCTs (3365 STEMI patients). BMSC therapy did not significantly decrease mortality (risk ratio, 0.71; 95% confidence interval, 0.45-1.11; I2, 0%; absolute risk reduction, 0.1%; 95% confidence interval, -0.71 to 0.91; 40 trials; 3289 participants; I2, 0%; low strength of evidence). BMSC therapy had no effect on secondary or adverse outcomes. Trial sequential analysis for all-cause mortality showed no evidence of a clinically important difference, with a very low probability that future studies can change the current conclusion. CONCLUSIONS: On the basis of evidence from 42 RCTs published in the past 15 years, we provide conclusive evidence for a lack of beneficial effect for autologous BMSC therapy in patients with STEMI.

Iatrogenic Great Cardiac Vein Anastomosis during Coronary Artery Bypass Surgery.

Inadvertent anastomosis of the left internal mammary artery (LIMA) or a saphenous vein graft (SVG) to the great cardiac vein (GCV) is a rare complication of coronary artery bypass grafting (CABG). We present two cases with a LIMA to GCV and a SVG to GCV anastomosis, respectively, resulting in angina and dyspnea in the postoperative state. As an alternative to repeat CABG, both patients underwent percutaneous coronary intervention with percutaneous coil embolization or implantation of an Amplatzer vascular plug within the bypass graft to GCV conduit. This report highlights that percutaneous options exist for the relief of ischemic symptoms in this rare clinical setting.

Longitudinal treatment patterns with ADP receptor inhibitors after myocardial infarction: Insights from the Canadian Observational AntiPlatelet sTudy.

BACKGROUND: After myocardial infarction (MI) treated with percutaneous coronary intervention (PCI), guidelines recommend dual antiplatelet therapy (DAPT) with aspirin and an ADP receptor inhibitor (ADPri) for at least 1year. However, whether real-world Canadian practice patterns reflect this recommendation is unknown. METHODS: We studied 2175 MI patients treated with PCI and discharged from 26 Canadian hospitals between 12/2011 and 05/2013 in the Canadian Observational Antiplatelet sTudy (COAPT). Hierarchical Cox proportional hazard regression modeling was used to determine baseline demographic and clinical factors associated with duration of ADPri therapy post-discharge. RESULTS: At index-hospitalization discharge, 1597 (73%) patients were treated with clopidogrel, 220 (10%) with prasugrel, and 358 (17%) with ticagrelor. ADPri was discontinued prior to 1year in 474 (21.8%) patients; discontinuation rates were lowest for patients discharged on prasugrel (17.7%), compared with clopidogrel (22.5%) or ticagrelor (21.0%), (log rank test, p=0.03). In addition to regional variability, factors associated with shorter ADPri duration included older age, low body weight, Killip III/IV heart failure, atrial fibrillation, ticagrelor on discharge, and bare metal stent use, while longer ADPri duration was associated with history of prior MI. CONCLUSIONS: One in five PCI-treated MI patients did not complete Canadian guideline-recommended 1-year course of ADPri treatment. Premature ADPri discontinuation was most strongly associated with factors that increase the risk of bleeding. Further study is required to assess the clinical implications of premature ADPri discontinuation on patient outcomes.

Adoption of the hybrid CTO approach by a single non-CTO operator: procedural and clinical outcomes.

BACKGROUND: The feasibility of adopting the "hybrid" approach by a single operator without prior experience in percutaneous coronary intervention (PCI) of chronic total occlusions (CTOs) has not been described. METHODS: Consecutive patients who underwent CTO-PCI by a single operator using the "hybrid" approach between 2012 and 2013 formed the analytic cohort. No patient was declined on the basis of angiographic findings. Clinical and angiographic characteristics together with procedural and hospital outcomes are described. RESULTS: During the study period, a total of 48 consecutive patients underwent PCI of 50 CTOs. Mean age was 63.4 ± 9.4 years and most patients (83%) were men. The right coronary artery (RCA) was the most commonly treated CTO vessel (54%) and mean J-CTO score was 2.3 ± 1.1. A primary retrograde approach was chosen for 33% of lesions and 40% required use of an epicardial collateral vessel. The primary strategy was effective in 65% of successful cases, 35% required one change in strategy, and 15% requiring two strategy changes. Procedural success rate was 92%. The median number of stents used was 3 (interquartile range [IQR], 2-4] and the total stent length was 73 mm [IQR, 38-96 mm). Mean contrast volume was 356.4 ± 148.3 mL and the mean air kerma radiation exposure was 3.5 ± 2.0 Gy. No patient experienced a major periprocedural complication. CONCLUSION: The "hybrid" approach to CTO-PCI can be successfully adopted by a single operator with excellent early procedural success and low complication rates, despite a lack of prior CTO-PCI experience.

Radiation dose reduction in the cardiac catheterization laboratory utilizing a novel protocol.

OBJECTIVES: This study reports the results a novel radiation reduction protocol (RRP) system for coronary angiography and interventional procedures and the determinants of radiation dose. BACKGROUND: The cardiac catheterization laboratory is an important source of radiation and should be kept in good working order with dose-reduction and monitoring capabilities. METHODS: All diagnostic coronary angiograms and percutaneous coronary interventions from a single catheterization laboratory were analyzed 2 months before and after RRP implementation. The primary outcome was the relative dose reduction at the interventional reference point. Separate analyses were done for conventional 15 frames/s (FPS) and at reduced 7.5 FPS post-RRP groups. RESULTS: A total of 605 patients underwent coronary angiography (309 before RRP and 296 after RRP), with 129 (42%) and 122 (41%) undergoing percutaneous coronary interventions before and after RRP, respectively. With RRP, a 48% dose reduction (1.07 ± 0.05 Gy vs. 0.56 ± 0.03 Gy, p < 0.0001) was obtained, 35% with 15 FPS RRP (0.70 ± 0.05 Gy, p < 0.0001) and 62% with 7.5 FPS RRP (0.41 ± 0.03 Gy, p < 0.001). Similar dose reductions for diagnostic angiograms and percutaneous coronary interventions were noted. There was no change in the number of stents placed or vessels intervened on. Increased dose was associated with male sex, radial approach, increasing body mass index, cine runs, and frame rates. Using a multivariable model, a 48% relative risk with RRP (p < 0.001), 44% with 15 FPS RRP and 68% with 7.5 FPS RRP was obtained. CONCLUSIONS: We demonstrate a highly significant 48.5% adjusted radiation dose reduction using a novel algorithm, which needs strong consideration among interventional cardiology practice.

Cardiac Outcomes Through Digital Evaluation (CODE) STEMI project: prehospital digitally-assisted reperfusion strategies.

BACKGROUND: Guidelines for reperfusion in ST-elevation myocardial infarction (STEMI) were recently adopted by the Canadian Cardiovascular Society. We have developed a blended model of prehospital thrombolytic (PHL) therapy or primary percutaneous coronary intervention (PPCI) activation, in order to achieve guideline times. METHODS: In our urban centre of 658,700 people, emergency medical services (EMS) were trained to perform and screen electrocardiograms (ECGs) for suspected STEMI. Suspected ECGs were transmitted to a physician's hand-held device. If the physician confirmed the diagnosis they coordinated initiation of either PHL or PPCI. In cases where physicians found the prehospital ECG negative for STEMI (PHENST), patients were transported to the closest emergency room. RESULTS: From July 21, 2008 to July 21, 2010, the Cardiac Outcomes Through Digital Evaluation (CODE) STEMI project received 380 transmitted calls. There were 226 confirmed STEMI by the on-call physician, 158 (70%) received PPCI, 48 (21%) received PHL, and 20 (9%) had angiography but no revascularization. The PPCI, median time from first medical contact to reperfusion was 76 minutes (interquartile range [IQR], 64-93). For PHL, median time from first medical contact to needle was 32 minutes (IQR, 29-39). The overall mortality rate for the STEMI patients was 8% (PHL = 4 [8.3%], PPCI = 8 [5%], medical therapy = 7 [35%]). There were 154 PHENST patients, 44% later diagnosed with acute coronary syndrome. The mortality rate for PHENST was 14%. CONCLUSIONS: Through a model of EMS prehospital ECG interpretation, digital transmission, direct communication with a physician, and rapid coordinated service, we demonstrate that benchmark reperfusion times in STEMI can be achieved.

The ability to achieve complete revascularization is associated with improved in-hospital survival in cardiogenic shock due to myocardial infarction: Manitoba cardiogenic SHOCK Registry investigators.

OBJECTIVES: To identify predictors of survival in a retrospective multicentre cohort of patients with cardiogenic shock undergoing coronary angiography and to address whether complete revascularization is associated with improved survival in this cohort. BACKGROUND: Early revascularization is the standard of care for cardiogenic shock. Coronary bypass grafting and percutaneous intervention have complimentary roles in achieving this revascularization. METHODS: A total of 210 consecutive patients (mean age 66 ± 12 years) at two tertiary centres from 2002 to 2006 inclusive with a diagnosis of cardiogenic shock were evaluated. Univariate and multivariate predictors of in-hospital survival were identified utilizing logistic regression. RESULTS: ST elevation infarction occurred in 67% of patients. Thrombolysis was administered in 34%, PCI was attempted in 62% (88% stented, 76% TIMI 3 flow), CABG was performed in 22% (2.7 grafts, 14 valve procedures), and medical therapy alone was administered to the remainder. The overall survival to discharge was 59% (CABG 68%, PCI 57%, medical 48%). Independent predictors of mortality included complete revascularization (P = 0.013, OR = 0.26 (95% CI: 0.09-0.76), hyperlactatemia (P = 0.046, OR = 1.14 (95% CI: 1.002-1.3) per mmol increase), baseline renal insufficiency (P = 0.043, OR = 3.45, (95% CI: 1.04-11.4), and the presence of anoxic brain injury (P = 0.008, OR = 8.22 (95% CI: 1.73-39.1). Within the STEMI with concomitant multivessel coronary disease subgroup of this population (N = 101), independent predictors of survival to discharge included complete revascularization (P = 0.03, OR = 2.5 (95% CI: 1.1-6.2)) and peak lactate (P = 0.02). CONCLUSIONS: The ability to achieve complete revascularization may be strongly associated with improved in-hospital survival in patients with cardiogenic shock.

Relationship between renal function and outcomes in high-risk patients with non-ST-segment elevation acute coronary syndromes: results from SYNERGY.

BACKGROUND: Chronic kidney disease (CKD) is a risk factor for coronary heart disease and bleeding with antithrombotic therapy in patients with acute coronary syndromes (ACS). We evaluated the effect of renal function on efficacy and outcomes in high-risk patients with NSTE ACS in the SYNERGY trial. METHODS: Creatinine clearance (CrCl) at the time of randomization was analyzed as a continuous variable added to multivariable logistic regression models for 30-day death or MI, non-CABG-associated TIMI major bleeding, GUSTO severe bleeding, and transfusion in the overall study population, patients undergoing coronary angiography, and patients undergoing PCI. RESULTS: Of 9838 patients with a CrCl value, 70.6% (N=6950) had CrCl≥60 mL/min, 27.8% (N=2732) had CrCl 30-59 mL/min, and 1.6% (N=156) had CrCl<30 mL/min. No randomized treatment by CrCl interaction test was found to be statistically significant, suggesting renal insufficiency affected enoxaparin and unfractionated heparin outcomes similarly. After adjustment, CrCl was an independent predictor of 30-day death or MI (OR 1.06, 95% CI 1.03-1.09), TIMI major bleeding (OR 1.06, 95% CI 1.02-1.10), GUSTO severe bleeding (OR 1.10, 95% CI 1.03-1.17), and transfusion (OR 1.07, 95% CI 1.04-1.11). CONCLUSIONS: Patients with CKD had higher rates of 30-day death or MI and bleeding than those without CKD, regardless of randomized antithrombin therapy. While this analysis suggests that there is a rise in bleeding events as CrCl falls for patients in either treatment group, it is unknown whether a reduction in dose would decrease bleeding risk.

Effect of operator and institutional volume on clinical outcomes after percutaneous coronary interventions performed in Canada and the United States: a brief report from the Enhanced Suppression of the Platelet glycoprotein IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) study.

BACKGROUND: The Enhanced Suppression of the Platelet glycoprotein IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial compared the use of eptifibatide with placebo in 2064 coronary intervention patients. It was previously reported that Canadian patients had reduced rates of 30-day and one-year death, myocardial infarction (MI) or target vessel revascularization (TVR) compared with patients in the United States (US). OBJECTIVE: To examine whether operator or institutional volume differences explain the regional variation in clinical outcome. METHODS AND RESULTS: Each site received an operator and institutional volume survey. Fifty-seven sites (62%) returned complete data on 1338 patients. In this smaller cohort, Canadian patients had reduced rates of 30-day and one-year death, MI or TVR compared with US patients (6.3% versus 10.3% and 14.9% versus 20.1%, respectively; P<0.05 for both comparisons). Among 176 physicians with a median of 13 years experience, the median operator volume was 200 cases per year. Operators with fewer than 100 cases per year had higher rates of 30-day death, MI or TVR (13.2% versus 8.7%; P=0.18) and large MI (7.7% versus 3.3%; P=0.06) than those with 100 or more cases per year. The median institutional volume was 1064 cases per year. Canadian and US centres had similar operator and institutional volumes. By multivariate modelling, operator volume was not predictive of adverse clinical events. However, the rates of 30-day and one-year death, MI or TVR fell by 3% for every 100 patients treated by the institution (OR 0.97; P=0.058 and P=0.002, respectively). Enrollment in Canada was associated with improved outcomes at 30 days (OR 0.50; P=0.001) and one year (OR 0.66; P=0.001) despite inclusion of volume variables in the models. CONCLUSIONS: In the ESPRIT study, institutional volume was associated with a modest reduction in risk of death, MI or TVR over short- and long-term follow-up periods. The Canadian and US investigators and institutions selected in ESPRIT had similar annual procedural volumes. Therefore, volume variables did not explain the differential risk of clinical events observed for patients enrolled in the two countries.

Temporal spectrum of ischemic complications with percutaneous coronary intervention: the ESPRIT experience.

We determined the timing of ischemic complications within 30 days after percutaneous coronary intervention (PCI) in patients enrolled in the Enhanced Suppression of the Platelet IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial. Complications (death, myocardial infarction [MI], target vessel revascularization) occurred in 178 of 2064 patients (8.6%) within 30 days. More than 85% of complications occurred within the 24 hours following randomization, with the greatest risk hazard at 12-18 hours. Unexpectedly, 31% of patients who ultimately met criteria for an endpoint MI within 24 hours of PCI had completely normal CK-MB concentrations at the first 6-hour measurement. There was no rebound increase in events after cessation of eptifibatide. Treatment benefit persisted to 30 days. Post-procedural MI is often not detected until greater than or equal to 12 hours after PCI. Treatment with a glycoprotein IIb/IIIa inhibitor is the only modifiable parameter that reduces the risk for early ischemic complications.

Immediate protamine administration and sheath removal following percutaneous coronary intervention: a prospective study of 429 patients.

We tested the approach of reversing anticoagulation following PCI and immediate sheath removal in 429 consecutive patients. On completion of the PCI, protamine was administered, and the vascular sheath was immediately removed. Stents were used in 364 patients (85%) and GP IIb/IIIa inhibitors were used in 52 patients (12%). Time to achieve hemostasis was 30 +/- 17 min. Minor groin bleeding occurred in six patients. One patient required repair of femoral pseudoaneurysm. Mean creatine kinase at 8 and 16 hr post-PCI were 129 +/- 35 and 145 +/- 32 units, respectively. Creatine kinase rose to > 3 times normal in 12 out of 350 patients (3.4%). Prior to 48 hr, eight patients (1.9%) required emergency PCI or coronary bypass surgery. Follow-up at 30 days observed no deaths and only three target vessel revascularizations (0.7%). In conclusion, immediate reversal of anticoagulation and sheath removal after PCI is safe and feasible.