Multicenter, Phase 2, Randomized Controlled Study of the Efficacy and Safety of Etripamil Nasal Spray for the Acute Reduction of Rapid Ventricular Rate in Patients With Symptomatic Atrial Fibrillation (ReVeRA-201).

BACKGROUND: Despite chronic therapies, atrial fibrillation (AF) leads to rapid ventricular rates (RVR) often requiring intravenous treatments. Etripamil is a fast-acting, calcium-channel blocker administered intranasally affecting the atrioventricular node within minutes. METHODS: Reduction of Ventricular Rate in Patients with Atrial Fibrillation evaluated the efficacy and safety of etripamil for the reduction of ventricular rate (VR) in patients presenting urgently with AF-RVR (VR ≥110 beats per minute [bpm]), was randomized, double-blind, placebo-controlled, and conducted in Canada and the Netherlands. Patients presenting urgently with AF-RVR were randomized (1:1, etripamil nasal spray 70 mg: placebo nasal spray). The primary objective was to demonstrate the effectiveness of etripamil in reducing VR in AF-RVR within 60 minutes of treatment. Secondary objectives assessed achievement of VR <100 bpm, reduction by ≥10% and ≥20%, relief of symptoms and treatment effectiveness; adverse events; and additional measures to 360 minutes. RESULTS: Sixty-nine patients were randomized, 56 dosed with etripamil (n=27) or placebo (n=29). The median age was 65 years; 39% were female patients; proportions of AF types were similar between groups. The difference of mean maximum reductions in VR over 60 minutes, etripamil versus placebo, adjusting for baseline VR, was -29.91 bpm (95% CI, -40.31 to -19.52; P<0.0001). VR reductions persisted up to 150 minutes. Significantly greater proportions of patients receiving etripamil achieved VR reductions <100 bpm (with longer median duration <100 bpm), or VR reduction by ≥10% or ≥20%, versus placebo. VR reduction ≥20% occurred in 66.7% of patients in the etripamil arm and no patients in placebo. Using the Treatment Satisfaction Questionnaire for Medication-9, there was significant improvement in satisfaction on symptom relief and treatment effectiveness with etripamil versus placebo. Serious adverse events were rare; 1 patient in the etripamil arm experienced transient severe bradycardia and syncope, assessed as due to hypervagotonia. CONCLUSIONS: Intranasal etripamil 70 mg reduced VR and improved symptom relief and treatment satisfaction. These data support further development of self-administered etripamil for the treatment of AF-RVR. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique Identifier: NCT04467905.

Comparison of Outcomes of Invasive or Conservative Management of Chronic Coronary Disease in Four Randomized Controlled Trials.

Revascularization and medical therapy for chronic coronary disease have both evolved significantly over the last 50 years. A total of 4 contemporary randomized controlled trials- Clinical Outcomes Utilizing Revascularization and Aggressive drug Evaluation (COURAGE), Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D), Fractional Flow Reserve versus Angiography for Multivessel Evaluation 2 (FAME 2), and International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA)-have assessed the incremental benefit of revascularization when added to secondary prevention with intensive pharmacologic and lifestyle intervention. We reviewed these 4 seminal studies with the objective of marshaling evidence to better frame how these results should apply to clinical decision making. These studies differed in study design, end points, intensity of treatment, and revascularization techniques. Nevertheless, they all demonstrate similar rates of "hard" clinical events with invasive and conservative management, and varying degrees of benefit in angina-related quality of life with revascularization. In conclusion, although controversy persists concerning the role of revascularization because of differing interpretations of the clinical trial evidence, we contend that instead of being competing management strategies, invasive and conservative approaches are complementary.

Comparison of Days Alive Out of Hospital With Initial Invasive vs Conservative Management: A Prespecified Analysis of the ISCHEMIA Trial.

Importance: Traditional time-to-event analyses rate events occurring early as more important than later events, even if later events are more severe, eg, death. Days alive out of hospital (DAOH) adds a patient-focused perspective beyond trial end points. Objective: To compare DAOH between invasive management and conservative management, including invasive protocol-assigned stays, in the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) randomized clinical trial. Design, Setting, and Participants: In this prespecified analysis of the ISCHEMIA trial, DAOH was compared between 5179 patients with stable coronary disease and moderate or severe ischemia randomized to invasive management or conservative management. Participants were recruited from 320 sites in 37 countries. Stays included overnight stays in hospital or extended care facility (skilled nursing facility, rehabilitation, or nursing home). DAOH was separately analyzed excluding invasive protocol-assigned procedures. Data were collected from July 2012 to June 2019, and data were analyzed from July 2020 to April 2021. Interventions: Invasive management with angiography and revascularization if feasible or conservative management, with both groups receiving optimal medical therapy. Main Outcomes and Measures: The hypothesis was formulated before data lock in July 2020. The primary end point was mean DAOH per patient between randomization and 4 years. Initial stays for invasive protocol-assigned procedures were prespecified to be excluded. Results: Of 5179 included patients, 1168 (22.6%) were female, and the median (interquartile range) age was 64 (58-70) years. The average DAOH was higher in the conservative management group compared with the invasive management group at 1 month (30.8 vs 28.4 days; P < .001), 1 year (362.2 vs 355.9 days; P < .001), and 2 years (718.4 vs 712.1 days; P = .001). At 4 years, the 2 groups' DAOH were not significantly different (1415.0 vs 1412.2 days; P = .65). In the invasive management group, 2434 of 4002 stays (60.8%) were for protocol-assigned procedures. There were no clear differences at any time point in DAOH when protocol-assigned procedures were excluded from the invasive management group. There were more hospital and extended care stays in the invasive management vs conservative management group during follow-up (4002 vs 1897; P < .001). Excluding protocol-assigned procedures, there were fewer stays in the invasive vs conservative group (1568 vs 1897; P = .001). Cardiovascular stays following the initial assigned procedures were lower in the invasive management group (685 of 4002 [17.1%] vs 1095 of 1897 [57.8%]; P < .001) due to decreased spontaneous myocardial infarction stays (65 [1.6%] vs 123 [6.5%]; P < .001) and unstable angina stays (119 [3.0%] vs 216 [11.4%]; P < .001). Conclusions and Relevance: DAOH was higher for patients in the conservative management group in the first 2 years but not different at 4 years. DAOH was decreased early in the invasive management group due to protocol-assigned procedures. Hospital stays for myocardial infarction and unstable angina during follow-up were lower in the invasive management group. DAOH provides a patient-focused metric that can be used by clinicians and patients in shared decision-making for management of stable coronary artery disease. Trial Registration: ClinicalTrials.gov Identifier: NCT01471522.

CT Angiography Followed by Invasive Angiography in Patients With Moderate or Severe Ischemia-Insights From the ISCHEMIA Trial.

OBJECTIVES: This study aimed to examine the concordance of coronary computed tomographic angiography (CCTA) assessment of coronary anatomy and invasive coronary angiography (ICA) as the reference standard in patients enrolled in the ISCHEMIA (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches). BACKGROUND: Performance of CCTA compared with ICA has not been assessed in patients with very high burdens of stress-induced ischemia and a high likelihood of anatomically significant coronary artery disease (CAD). A blinded CCTA was performed after enrollment to exclude patients with left main (LM) disease or no obstructive CAD before randomization to an initial conservative or invasive strategy, the latter guided by ICA and optimal revascularization. METHODS: Rates of concordance were calculated on a per-patient basis in patients randomized to the invasive strategy. Anatomic significance was defined as ≥50% diameter stenosis (DS) for both modalities. Sensitivity analyses using a threshold of ≥70% DS for CCTA or considering only CCTA images of good-to-excellent quality were performed. RESULTS: In 1,728 patients identified by CCTA as having no LM disease ≥50% and at least single-vessel CAD, ICA confirmed 97.1% without LM disease ≥50%, 92.2% with at least single-vessel CAD and no LM disease ≥50%, and only 4.9% without anatomically significant CAD. Results using a ≥70% DS threshold or only CCTA of good-to-excellent quality showed similar overall performance. CONCLUSIONS: CCTA before randomization in ISCHEMIA demonstrated high concordance with subsequent ICA for identification of patients with angiographically significant disease without LM disease.

Myocardial Infarction in the ISCHEMIA Trial: Impact of Different Definitions on Incidence, Prognosis, and Treatment Comparisons.

BACKGROUND: In the ISCHEMIA trial (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches), an initial invasive strategy did not significantly reduce rates of cardiovascular events or all-cause mortality in comparison with a conservative strategy in patients with stable ischemic heart disease and moderate/severe myocardial ischemia. The most frequent component of composite cardiovascular end points was myocardial infarction (MI). METHODS: ISCHEMIA prespecified that the primary and major secondary composite end points of the trial be analyzed using 2 MI definitions. For procedural MI, the primary MI definition used creatine kinase-MB as the preferred biomarker, whereas the secondary definition used cardiac troponin. Procedural thresholds were >5 times the upper reference level for percutaneous coronary intervention and >10 times for coronary artery bypass grafting. Procedural MI definitions included (1) a category of elevated biomarker only events with much higher biomarker thresholds, (2) new ST-segment depression of ≥1 mm for the primary and ≥0.5 mm for the secondary definition, and (3) new coronary dissections >National Heart, Lung, and Blood Institute grade 3. We compared MI type, frequency, and prognosis by treatment assignment using both MI definitions. RESULTS: Procedural MIs accounted for 20.1% of all MI events with the primary definition and 40.6% of all MI events with the secondary definition. Four-year MI rates in patients undergoing revascularization were more frequent with the invasive versus conservative strategy using the primary (2.7% versus 1.1%; adjusted hazard ratio [HR], 2.98 [95% CI, 1.87-4.73]) and secondary (8.2% versus 2.0%; adjusted HR, 5.04 [95% CI, 3.64-6.97]) MI definitions. Type 1 MIs were less frequent with the invasive versus conservative strategy using the primary (3.40% versus 6.89%; adjusted HR, 0.53 [95% CI, 0.41-0.69]; P<0.0001) and secondary (3.48% versus 6.89%; adjusted HR, 0.53 [95% CI, 0.41-0.69]; P<0.0001) definitions. The risk of subsequent cardiovascular death was higher after a type 1 MI than after no MI using the primary (adjusted HR, 3.38 [95% CI, 2.03-5.61]; P<0.001) or secondary MI definition (adjusted HR, 3.52 [2.11-5.88]; P<0.001). CONCLUSIONS: In ISCHEMIA, type 1 MI events using the primary and secondary definitions during 5-year follow-up were more frequent with an initial conservative strategy and associated with subsequent cardiovascular death. Procedural MI rates were greater in the invasive strategy and with the use of the secondary MI definition. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01471522.

Health-Status Outcomes with Invasive or Conservative Care in Coronary Disease.

BACKGROUND: In the ISCHEMIA trial, an invasive strategy with angiographic assessment and revascularization did not reduce clinical events among patients with stable ischemic heart disease and moderate or severe ischemia. A secondary objective of the trial was to assess angina-related health status among these patients. METHODS: We assessed angina-related symptoms, function, and quality of life with the Seattle Angina Questionnaire (SAQ) at randomization, at months 1.5, 3, and 6, and every 6 months thereafter in participants who had been randomly assigned to an invasive treatment strategy (2295 participants) or a conservative strategy (2322). Mixed-effects cumulative probability models within a Bayesian framework were used to estimate differences between the treatment groups. The primary outcome of this health-status analysis was the SAQ summary score (scores range from 0 to 100, with higher scores indicating better health status). All analyses were performed in the overall population and according to baseline angina frequency. RESULTS: At baseline, 35% of patients reported having no angina in the previous month. SAQ summary scores increased in both treatment groups, with increases at 3, 12, and 36 months that were 4.1 points (95% credible interval, 3.2 to 5.0), 4.2 points (95% credible interval, 3.3 to 5.1), and 2.9 points (95% credible interval, 2.2 to 3.7) higher with the invasive strategy than with the conservative strategy. Differences were larger among participants who had more frequent angina at baseline (8.5 vs. 0.1 points at 3 months and 5.3 vs. 1.2 points at 36 months among participants with daily or weekly angina as compared with no angina). CONCLUSIONS: In the overall trial population with moderate or severe ischemia, which included 35% of participants without angina at baseline, patients randomly assigned to the invasive strategy had greater improvement in angina-related health status than those assigned to the conservative strategy. The modest mean differences favoring the invasive strategy in the overall group reflected minimal differences among asymptomatic patients and larger differences among patients who had had angina at baseline. (Funded by the National Heart, Lung, and Blood Institute and others; ISCHEMIA ClinicalTrials.gov number, NCT01471522.).

Initial Invasive or Conservative Strategy for Stable Coronary Disease.

BACKGROUND: Among patients with stable coronary disease and moderate or severe ischemia, whether clinical outcomes are better in those who receive an invasive intervention plus medical therapy than in those who receive medical therapy alone is uncertain. METHODS: We randomly assigned 5179 patients with moderate or severe ischemia to an initial invasive strategy (angiography and revascularization when feasible) and medical therapy or to an initial conservative strategy of medical therapy alone and angiography if medical therapy failed. The primary outcome was a composite of death from cardiovascular causes, myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. A key secondary outcome was death from cardiovascular causes or myocardial infarction. RESULTS: Over a median of 3.2 years, 318 primary outcome events occurred in the invasive-strategy group and 352 occurred in the conservative-strategy group. At 6 months, the cumulative event rate was 5.3% in the invasive-strategy group and 3.4% in the conservative-strategy group (difference, 1.9 percentage points; 95% confidence interval [CI], 0.8 to 3.0); at 5 years, the cumulative event rate was 16.4% and 18.2%, respectively (difference, -1.8 percentage points; 95% CI, -4.7 to 1.0). Results were similar with respect to the key secondary outcome. The incidence of the primary outcome was sensitive to the definition of myocardial infarction; a secondary analysis yielded more procedural myocardial infarctions of uncertain clinical importance. There were 145 deaths in the invasive-strategy group and 144 deaths in the conservative-strategy group (hazard ratio, 1.05; 95% CI, 0.83 to 1.32). CONCLUSIONS: Among patients with stable coronary disease and moderate or severe ischemia, we did not find evidence that an initial invasive strategy, as compared with an initial conservative strategy, reduced the risk of ischemic cardiovascular events or death from any cause over a median of 3.2 years. The trial findings were sensitive to the definition of myocardial infarction that was used. (Funded by the National Heart, Lung, and Blood Institute and others; ISCHEMIA ClinicalTrials.gov number, NCT01471522.).

Association of Sex With Severity of Coronary Artery Disease, Ischemia, and Symptom Burden in Patients With Moderate or Severe Ischemia: Secondary Analysis of the ISCHEMIA Randomized Clinical Trial.

Importance: While many features of stable ischemic heart disease vary by sex, differences in ischemia, coronary anatomy, and symptoms by sex have not been investigated among patients with moderate or severe ischemia. The enrolled ISCHEMIA trial cohort that underwent coronary computed tomographic angiography (CCTA) was required to have obstructive coronary artery disease (CAD) for randomization. Objective: To describe sex differences in stress testing, CCTA findings, and symptoms in ISCHEMIA trial participants. Design, Setting, and Participants: This secondary analysis of the multicenter ISCHEMIA randomized clinical trial analyzed baseline characteristics of patients with stable ischemic heart disease. Individuals were enrolled from July 2012 to January 2018 based on local reading of moderate or severe ischemia on a stress test, after which blinded CCTA was performed in most. Core laboratories reviewed stress tests and CCTAs. Participants with no obstructive CAD or with left main CAD of 50% or greater were excluded. Those who met eligibility criteria including CCTA (if performed) were randomized to a routine invasive or a conservative management strategy (N = 5179). Angina was assessed using the Seattle Angina Questionnaire. Analysis began October 1, 2018. Interventions: CCTA and angina assessment. Main Outcomes and Measures: Sex differences in stress test, CCTA findings, and symptom severity. Results: Of 8518 patients enrolled, 6256 (77%) were men. Women were more likely to have no obstructive CAD (<50% stenosis in all vessels on CCTA) (353 of 1022 [34.4%] vs 378 of 3353 [11.3%]). Of individuals who were randomized, women had more angina at baseline than men (median [interquartile range] Seattle Angina Questionnaire Angina Frequency score: 80 [70-100] vs 90 [70-100]). Women had less severe ischemia on stress imaging (383 of 919 [41.7%] vs 1361 of 2972 [45.9%] with severe ischemia; 386 of 919 [42.0%] vs 1215 of 2972 [40.9%] with moderate ischemia; and 150 of 919 [16.4%] vs 394 of 2972 [13.3%] with mild or no ischemia). Ischemia was similar by sex on exercise tolerance testing. Women had less extensive CAD on CCTA (205 of 568 women [36%] vs 1142 of 2418 men [47%] with 3-vessel disease; 184 of 568 women [32%] vs 754 of 2418 men [31%] with 2-vessel disease; and 178 of 568 women [31%] vs 519 of 2418 men [22%] with 1-vessel disease). Female sex was independently associated with greater angina frequency (odds ratio, 1.41; 95% CI, 1.13-1.76). Conclusions and Relevance: Women in the ISCHEMIA trial had more frequent angina, independent of less extensive CAD, and less severe ischemia than men. These findings reflect inherent sex differences in the complex relationships between angina, atherosclerosis, and ischemia that may have implications for testing and treatment of patients with suspected stable ischemic heart disease. Trial Registration: ClinicalTrials.gov Identifier: NCT01471522.

Baseline Predictors of Low-Density Lipoprotein Cholesterol and Systolic Blood Pressure Goal Attainment After 1 Year in the ISCHEMIA Trial.

BACKGROUND: Risk factor control is the cornerstone of managing stable ischemic heart disease but is often not achieved. Predictors of risk factor control in a randomized clinical trial have not been described. METHODS AND RESULTS: The ISCHEMIA trial (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches) randomized individuals with at least moderate inducible ischemia and obstructive coronary artery disease to an initial invasive or conservative strategy in addition to optimal medical therapy. The primary aim of this analysis was to determine predictors of meeting trial goals for LDL-C (low-density lipoprotein cholesterol, goal <70 mg/dL) or systolic blood pressure (SBP, goal <140 mm Hg) at 1 year post-randomization. We included all randomized participants in the ISCHEMIA trial with baseline and 1-year LDL-C and SBP values by January 28, 2019. Among the 3984 ISCHEMIA participants (78% of 5179 randomized) with available data, 35% were at goal for LDL-C, and 65% were at goal for SBP at baseline. At 1 year, the percent at goal increased to 52% for LDL-C and 75% for SBP. Adjusted odds of 1-year LDL-C goal attainment were greater with older age (odds ratio [OR], 1.11 [95% CI, 1.03-1.20] per 10 years), lower baseline LDL-C (OR, 1.19 [95% CI, 1.17-1.22] per 10 mg/dL), high-intensity statin use (OR, 1.30 [95% CI, 1.12-1.51]), nonwhite race (OR, 1.32 [95% CI, 1.07-1.63]), and North American enrollment compared with other regions (OR, 1.32 [95% CI, 1.06-1.66]). Women were less likely than men to achieve 1-year LDL-C goal (OR, 0.68 [95% CI, 0.58-0.80]). Adjusted odds of 1-year SBP goal attainment were greater with lower baseline SBP (OR, 1.27 [95% CI, 1.22-1.33] per 10 mm Hg) and with North American enrollment (OR, 1.35 [95% CI, 1.04-1.76]). CONCLUSIONS: In ISCHEMIA, older age, male sex, high-intensity statin use, lower baseline LDL-C, and North American location predicted 1-year LDL-C goal attainment, whereas lower baseline SBP and North American location predicted 1-year SBP goal attainment. Future studies should examine the effects of sex disparities, international practice patterns, and provider behavior on risk factor control.

Clinical outcomes of bioresorbable vascular scaffold to treat all-comer patients. Are patients with acute coronary syndrome better candidates for bioresorbable vascular scaffold?

BACKGROUND: Scaffold thromboses (ST) and adverse events and have been associated with bioresorbable vascular scaffolds (BVS) at long-term, but their mechanism remains unclear. We sought to evaluate patient and lesion characteristics associated with mid- to long-term outcomes in patients treated with BVS. METHODS: This is an observational single-center, single-arm, retrospective study evaluating the performance of BVS in an all-comer population, including complex lesions (chronic total occlusions, long lesions), small vessels, and acute coronary syndromes (ACS). RESULTS: From May 2013 to June 2015, we included 482 patients (580 lesions) that were treated with BVS implantation including 71.2% treated for ACS in the present analysis. Mean follow-up period was 816.2 ±â€¯242.6 days. The primary endpoint was device oriented cardiac events (DOCE), defined as a composite of target-lesion revascularization (TLR), ST, target vessel myocardial infarction (TVMI) and cardiac death. Using Kaplan-Meier methods, the DOCE and ST rates at 36 months were 9.4% and 2.3%, respectively. No ST occurred between 2 and 3 years and ST occurred after 3 years, in one patient. Using multivariate analysis, ACS was the only significant predictor of lower rates of DOCE (p = 0.04, HR: 0.47, 95% CI: 0.23-0.96). CONCLUSIONS: In this large all-comers real-world cohort, lesions treated with BVS had non-negligible rates of DOCE and ST, in line with previous published randomized trials. The occurrence of very late event was very low after 24 months. ACS patients had lower rates of DOCE.

Simplifying the assessment of coronary artery stenosis by enhancing instantaneous wave free ratio.

BACKGROUND: Instantaneous wave free ratio (iFR) does not require adenosine, but has a relatively wide intermediate range where functional assessment remains inconclusive. In this pilot study, we sought to enhance iFR through with the use of intracoronary (IC) saline (iFRs) and contrast media (iFRc) and determine whether these techniques correlated well with fractional flow reserve (FFR). METHODS: Patients with coronary artery stenosis (CAS) associated with an iFR in the intermediate zone (≥0.86 and ≤0.93) were prospectively assessed with resting distal coronary pressure/aorta pressure (Pd/Pa), iFR, iFRs, iFRc and FFR. RESULTS: A total of 40 coronary lesions were studied (40 patients). Pearson correlation coefficients for FFR and iFR, FFR and iFRs, FFR and iFRc were respectively: 0.57 (P=0.0002), 0.80 (P<0.0001) and 0.77 (P<0.0001). Receiver-operating characteristic (ROC) curve analysis showed similar area under the curve (AUC) of iFRs and iFR [0.90 (95% CI: 0.76-1) vs. 0.89 (95% CI: 0.79-0.99), P=0.89]. Youden's index established cut-off values of ≤0.90 for iFR (sensitivity =91%, specificity =74%) and ≤0.78 for iFRs (sensitivity =73%, specificity =100%). In contrast, the AUC of iFRc was superior to the AUC of iFR [0.99 (95% CI: 0.98-1), P=0.049]. iFRc showed excellent accuracy and established cut-off values of ≤0.81 in predicting an FFR value of ≤0.80 (sensitivity =100%, specificity =93%). CONCLUSIONS: When iFR is in the intermediate zone, functional assessment of CAS by iFR is enhanced with the use of contrast media but not saline. This pilot study could be hypothesis generating for further study to enhance iFR specificity and sensibility.

Use of troponin assay 99th percentile as the decision level for myocardial infarction diagnosis.

BACKGROUND: The Universal Definition of Myocardial Infarction recommends the 99th percentile concentration of cardiac troponin in a normal reference population as part of the decision threshold to diagnose type 1 spontaneous myocardial infarction. Adoption of this recommendation in contemporary worldwide practice is not well known. METHODS: We performed a cohort study of 276 hospital laboratories in 31 countries participating in the National Heart, Lung, and Blood Institute-sponsored International Study of Comparative Health Effectiveness with Medical and Invasive Approaches trial. Each hospital laboratory's troponin assay manufacturer and model, the recommended assay's 99th percentile upper reference limit (URL) from the manufacturer's package insert, and the troponin concentration used locally as the decision level to diagnose myocardial infarction were ascertained. RESULTS: Twenty-one unique troponin assays from 9 manufacturers were used by the surveyed hospital laboratories. The ratio of the troponin concentration used locally to diagnose myocardial infarction to the assay manufacturer-determined 99th percentile URL was <1 at 19 (6.6%) laboratories, equal to 1 at 91 (31.6%) laboratories, >1 to ≤5 at 101 (35.1%) laboratories, >5 to ≤10 at 34 (11.8%) laboratories, and >10 at 43 (14.9%) laboratories. The variability in troponin decision level for myocardial infarction relative to the assay 99th percentile URL was present for laboratories in and outside of the United States, as well as for high- and standard-sensitivity assays. CONCLUSIONS: There is substantial hospital-level variation in the troponin threshold used to diagnose myocardial infarction; only one-third of hospital laboratories currently follow the Universal Definition of Myocardial Infarction consensus recommendation for use of troponin concentration at the 99th percentile of a normal reference population as the decision level to diagnose myocardial infarction. This variability across laboratories has important implications for both the diagnosis of myocardial infarction in clinical practice as well as adjudication of myocardial infarction in clinical trials.

Optimal medical therapy with or without percutaneous coronary intervention in women with stable coronary disease: A pre-specified subset analysis of the Clinical Outcomes Utilizing Revascularization and Aggressive druG Evaluation (COURAGE) trial.

OBJECTIVES: To determine whether sex-based differences exist in clinical effectiveness of percutaneous coronary intervention (PCI) when added to optimal medical therapy (OMT) in patients with stable coronary artery disease. BACKGROUND: A prior pre-specified unadjusted analysis from COURAGE showed that women randomized to PCI had a lower rate of death or myocardial infarction during a median 4.6-year follow-up with a trend for interaction with respect to sex. METHODS: We analyzed outcomes in 338 women (15%) and 1949 men (85%) randomized to PCI plus OMT versus OMT alone after adjustment for relevant baseline characteristics. RESULTS: There was no difference in treatment effect by sex for the primary end point (death or myocardial infarction; HR, 0.89; 95% CI, 0.77-1.03 for women and HR, 1.02, 95% CI 0.96-1.10 for men; P for interaction = .07). Although the event rate was low, a trend for interaction by sex was nonetheless noted for hospitalization for heart failure, with only women, but not men, assigned to PCI experiencing significantly fewer events as compared to their counterparts receiving OMT alone (HR, 0.59; 95% CI, 0.40-0.84, P < .001 for women and HR, 0.86; 95% CI, 0.74-1.01, P = .47 for men; P for interaction = .02). Both sexes randomized to PCI experienced significantly reduced need for subsequent revascularization (HR, 0.72; 95% CI, 0.62-0.83, P < .001 for women; HR, 0.84; 95% CI, 0.79-0.89, P < .001 for men; P for interaction = .02) with evidence of a sex-based differential treatment effect. CONCLUSION: In this adjusted analysis of the COURAGE trial, there were no significant differences in treatment effect on major outcomes between men and women. However, women assigned to PCI demonstrated a greater benefit as compared to men, with a reduction in heart failure hospitalization and need for future revascularization. These exploratory observations require further prospective study.

The value of core lab stress echocardiography interpretations: observations from the ISCHEMIA Trial.

BACKGROUND: Stress echocardiography (SE) is dependent on subjective interpretations. As a prelude to the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) Trial, potential sites were required to submit two SE, one with moderate or severe left ventricular (LV) myocardial ischemia and one with mild ischemia. We evaluated the concordance of site and core lab interpretations. METHODS: Eighty-one SE were submitted from 41 international sites. Ischemia was classified by the number of new or worsening segmental LV wall motion abnormalities (WMA): none, mild (1 or 2) or moderate or severe (3 or more) by the sites and the core lab. RESULTS: Core lab classified 6 SE as no ischemia, 35 mild and 40 moderate or greater. There was agreement between the site and core in 66 of 81 total cases (81%, weighted kappa coefficient [K] =0.635). Agreement was similar for SE type - 24 of 30 exercise (80%, K = 0.571) vs. 41 of 49 pharmacologic (84%, K = 0.685). The agreement between poor or fair image quality (27 of 36 cases, 75%, K = 0.492) was not as good as for the good or excellent image quality cases (39 of 45 cases, 87%, K = 0.755). Differences in concordance were noted for degree of ischemia with the majority of discordant interpretations (87%) occurring in patients with no or mild LV myocardial ischemia. CONCLUSIONS: While site SE interpretations are largely concordant with core lab interpretations, this appears dependent on image quality and the extent of WMA. Thus core lab interpretations remain important in clinical trials where consistency of interpretation across a range of cases is critical. TRIAL REGISTRATION: ClinicalTrials.gov NCT01471522.

The Benefits Conferred by Radial Access for Cardiac Catheterization Are Offset by a Paradoxical Increase in the Rate of Vascular Access Site Complications With Femoral Access: The Campeau Radial Paradox.

OBJECTIVES: The purpose of this study was to assess whether the benefits conferred by radial access (RA) at an individual level are offset by a proportionally greater incidence of vascular access site complications (VASC) at a population level when femoral access (FA) is performed. BACKGROUND: The recent widespread adoption of RA for cardiac catheterization has been associated with increased rates of VASCs when FA is attempted. METHODS: Logistic regression was used to calculate the adjusted VASC rate in a contemporary cohort of consecutive patients (2006 to 2008) where both RA and FA were used, and compared it with the adjusted VASC rate observed in a historical control cohort (1996 to 1998) where only FA was used. We calculated the adjusted attributable risk to estimate the proportion of VASC attributable to the introduction of RA in FA patients of the contemporary cohort. RESULTS: A total of 17,059 patients were included. At a population level, the VASC rate was higher in the overall contemporary cohort compared with the historical cohort (adjusted rates: 2.91% vs. 1.98%; odds ratio [OR]: 1.48, 95% confidence interval [CI]: 1.17 to 1.89; p = 0.001). In the contemporary cohort, RA patients experienced fewer VASC than FA patients (adjusted rates: 1.44% vs. 4.19%; OR: 0.33, 95% CI: 0.23 to 0.48; p < 0.001). We observed a higher VASC rate in FA patients in the contemporary cohort compared with the historical cohort (adjusted rates: 4.19% vs. 1.98%; OR: 2.16, 95% CI: 1.67 to 2.81; p < 0.001). This finding was consistent for both diagnostic and therapeutic catheterizations separately. The proportion of VASCs attributable to RA in the contemporary FA patients was estimated at 52.7%. CONCLUSIONS: In a contemporary population where both RA and FA were used, the safety benefit associated with RA is offset by a paradoxical increase in VASCs among FA patients. The existence of this radial paradox should be taken into consideration, especially among trainees and default radial operators.

Canadian Cardiovascular Society guidelines for the diagnosis and management of stable ischemic heart disease.

This overview provides a guideline for the management of stable ischemic heart disease. It represents the work of a primary and secondary panel of participants from across Canada who achieved consensus on behalf of the Canadian Cardiovascular Society. The suggestions and recommendations are intended to be of relevance to primary care and specialist physicians with an emphasis on rational deployment of diagnostic tests, expedited implementation of long- and short-term medical therapy, timely consideration of revascularization, and practical follow-up measures.

Prognostic implications of prominent R wave in electrocardiographic leads V1 or V2 in patients with acute coronary syndrome.

Although the adverse prognosis of Q-waves on electrocardiogram (ECG) has been demonstrated, the prognostic significance of prominent R wave (PRW) in V1 or V2 across a broad spectrum of acute coronary syndrome (ACS) has not been specifically studied. In the Global Registry of Acute Coronary Events (GRACE) and the Canadian ACS Registry I ECG substudies, admission ECGs were analyzed in an independent core ECG laboratory. PRW was defined as R wave >40 to 50 ms in V1 or V2, R/S ≥1 in V1, or R/S ≥1.5 in V2. Among 11,895 patients with ACS, 495 (4.2%) had PRW; they were less likely to have a history of hypertension or heart failure and had lower GRACE risk scores, but a higher incidence of ST-segment depression (all p ≤0.001). Patients with PRW had similar rates of in-hospital death (2.8% vs 4.1%, respectively, p = 0.15) but lower rates of in-hospital heart failure (8.5% vs 15.2%, respectively, p = 0.02) and 6-month mortality (4.6% vs 8.4%, respectively, p = 0.004). In multivariable analyses, PRW was not a significant independent predictor of in-hospital mortality (adjusted odds ratio = 0.99, 95% confidence interval 0.55 to 1.8) or 6-month mortality (adjusted odds ratio = 0.70, 95% confidence interval 0.43 to 1.15). Among 4,418 patients who underwent coronary angiography, those with PRW had a higher prevalence of left circumflex artery disease (62.5% vs 49.5%, respectively, p = 0.01). In conclusion, across the broad spectrum of patients with ACS, PRW provides no significant additional prognostic utility beyond comprehensive risk assessment using the GRACE risk score. PRW is more frequently associated with left circumflex artery disease.

Lessons learned from MPI and physiologic testing in randomized trials of stable ischemic heart disease: COURAGE, BARI 2D, FAME, and ISCHEMIA.

There is a preponderance of evidence that, in the setting of an acute coronary syndrome, an invasive approach using coronary revascularization has a morbidity and mortality benefit. However, recent stable ischemic heart disease (SIHD) randomized clinical trials testing whether the addition of coronary revascularization to guideline-directed medical therapy (GDMT) reduces death or major cardiovascular events have been negative. Based on the evidence from these trials, the primary role of GDMT as a front line medical management approach has been clearly defined in the recent SIHD clinical practice guideline; the role of prompt revascularization is less precisely defined. Based on data from observational studies, it has been hypothesized that there is a level of ischemia above which a revascularization strategy might result in benefit regarding cardiovascular events. However, eligibility for recent negative trials in SIHD has mandated at most minimal standards for ischemia. An ongoing randomized trial evaluating the effectiveness of randomization of patients to coronary angiography and revascularization as compared to no coronary angiography and GDMT in patients with moderate-severe ischemia will formally test this hypothesis. The current review will highlight the available evidence including a review of the published and ongoing SIHD trials.

Differential 1-year clinical outcomes for ST-segment elevation myocardial infarction related to stent thrombosis or saphenous vein graft thrombosis.

AIM: Thrombosis of stents and of saphenous vein grafts (SVG) remains a severe complication of either revascularization techniques that often are present as ST elevation myocardial infarction (STEMI). The aim of this longitudinal cohort study was to compare the 1-year clinical outcomes among STEMI patients requiring primary PCI due to stent thrombosis and graft occlusion presenting with STEMI. METHODS AND RESULTS: We prospectively collected data on all patients undergoing primary PCI at the Montreal Heart Institute between April 1, 2007 and March 30, 2008. Study patients were grouped according to the etiology of the STEMI: stent thrombosis, graft thrombosis, or atherosclerosis-related STEMIs (control group). The primary combined end-point, major adverse cardiac events (MACE), was defined as death, myocardial infarction, and target vessel revascularization within 12 months as primary end point. Of the 489 STEMI patients included in the study, 23 were due to stent thrombosis, 22 to graft thrombosis, and 444 in the control group. Stent and graft thromboses were associated with a higher MACE rates, 26.1 and 22.7%, respectively, compared to the control group, 9.3% (P = 0.004). Moreover, only stent thrombosis was associated with an increased risk of MACE (HR 2.57, confidence interval 95% 1.08-6.08. CONCLUSION: Patients with stent thrombosis present with higher rate of reinfarction while graft thrombosis is associated with an increase in 1-year cardiac mortality. Using multivariate analysis, higher MACE rates were associated with stent thrombosis as compared to graft thrombosis.