Effectiveness of medical therapy for treatment of idiopathic frequent premature ventricular complexes.

INTRODUCTION: The relative effectiveness of medical therapy compared with a conservative approach of monitoring in patients with idiopathic frequent premature ventricular complexes (PVCs) is uncertain. We evaluated the effectiveness of medical versus conservative therapy for frequent PVCs. METHODS: Patients with frequent PVCs (≥5%) were prospectively enrolled in this cohort study between 2016 and 2020. In patients with normal cardiac function and no structural heart disease, those receiving medical therapy were compared with controls without therapy. Patients were followed longitudinally for change in PVC burden and with serial echocardiography. RESULTS: Overall, 120 patients met inclusion criteria (mean: 56.5 ± 14.6 years, 54.2% female) with 53 on beta-blockers or calcium channel blockers (BBs/CCBs), 27 on Class I or III antiarrhythmic drugs (AADs), and 40 patients treated conservatively. Median initial PVC burden ranged from 15.5% to 20.6%. The median relative reduction of PVCs was 32.7%, 30.5%, and 81.3%, in the conservative therapy, BBs/CCBs, and AADs cohorts, respectively. AADs had greater PVC reduction compared with BBs/CCBs (p = 0.017) and conservative therapy (p = 0.045). PVC reduction to <1% was comparable across groups at 35.0%, 17.0%, 33.3%, respectively. Four patients (4/120, 3.3%) developed left ventricular dysfunction. Rates of adverse drug reactions and medication discontinuation were similar between groups, with no serious adverse events noted. CONCLUSION: In patients with idiopathic frequent PVCs, BB, and CCB have limited effectiveness in PVC reduction. Class I and III AADs have superior effectiveness for medical therapy in symptomatic patients, but only achieved complete PVC resolution suppression in one-third of patients.

Emergency Department Patients With Atrial Fibrillation or Flutter and an Acute Underlying Medical Illness May Not Benefit From Attempts to Control Rate or Rhythm.

STUDY OBJECTIVE: Although the management and outcomes of emergency department (ED) patients with atrial fibrillation or flutter have been explored, such studies have typically excluded patients with acute underlying medical illnesses. We seek to describe the ED treatment and outcomes of these complex patients with atrial fibrillation or flutter. METHODS: This retrospective descriptive cohort study used an ECG database from 2 urban EDs to identify consecutive ED patients with an ECG demonstrating atrial fibrillation or flutter from January 1, 2009, to December 31, 2009. We categorized patients with atrial fibrillation or flutter as "complex" according to prespecified criteria and then grouped them as being managed with rate or rhythm control attempts, or not. The primary outcome was safety of rate or rhythm control, measured by whether patients had a predefined adverse event or not. The secondary outcome was the success of rate or rhythm control, defined as rate control decreasing the pulse rate by 20 beats/min and successful rhythm control, both within 4 hours of treatment initiation. Descriptive statistics were used to compare the 2 groups. RESULTS: Four hundred sixteen complex patients with atrial fibrillation or flutter were identified. Patients managed with rate or rhythm control were similar in all baseline characteristics and illness distribution to patients who were not managed in this manner. The 135 patients with attempted rate control (105) or rhythm control (30) had 55 adverse events (40.7%; 95% confidence interval [CI] 32.5% to 49.5%), whereas the 281 patients not managed with rate or rhythm control had 20 adverse events (7.1%; 95% CI 4.5% to 10.9%), for a risk difference of 33.6% (95% CI 24.3% to 42.5%) and a relative risk of 5.7 (95% CI 3.6 to 9.1). Twenty of 105 patients (19.1%; 95% CI 12.3% to 28.1%) were successfully rate controlled, whereas 4 of 30 (13.3%; 95% CI 4.4% to 31.6%) were successfully rhythm controlled. CONCLUSION: In ED patients with complex atrial fibrillation or flutter, attempts at rate and rhythm control are associated with a nearly 6-fold higher adverse event rate than that for patients who are not managed with rate or rhythm control. Success rates of rate or rhythm control attempts appear low.

Cardiovascular risk among stable individuals suspected of having coronary artery disease with no modifiable risk factors: results from an international multicenter study of 5262 patients.

PURPOSE: To assess the prevalence, extent, severity, and risk of coronary artery disease (CAD) in patients suspected of having CAD but with no medically modifiable risk factors. MATERIALS AND METHODS: Institutional review board approval or waiver of consent was obtained at each center. This study was HIPAA compliant. From an international multicenter cohort study of 27 125 subjects undergoing coronary computed tomographic (CT) angiography from 12 centers, 5262 patients without known CAD and without modifiable risk factors were identified. CAD severity was defined as none (0%), mild (1%-49%), or obstructive (≥ 50%) on a per-patient, per-vessel, and per-segment basis. CAD presence, extent, and severity were related to incidence of major adverse cardiovascular event (MACE) by using Cox proportional hazards models. RESULTS: At a mean follow-up of 2.3 years ± 1.2 (standard deviation), MACE occurred in 106 patients. CAD was common for nonobstructive (n = 1452, 27%) and obstructive (n = 629, 12%) CAD. In risk-adjusted analysis, per-patient obstructive CAD (hazard ratio [HR], 6.64; 95% confidence interval [CI]: 3.68, 12.00; P ≤ .001) was related to MACE. MACE was associated with a dose-response relationship to the number of vessels exhibiting obstructive CAD, increasing risk for obstructive one-vessel (HR, 6.11; 95% CI: 3.22, 11.6; P ≤ .001), two-vessel (HR, 5.86; 95% CI: 2.75, 12.5; P ≤ .0001), or three-vessel or left main (HR, 11.69; 95% CI: 5.38, 25.4; P ≤ .001) CAD. The increased hazard for MACE of obstructive disease holds true for symptomatic (HR, 11.9; 95% CI: 4.81, 29.6; P ≤ .001) and asymptomatic (HR, 6.3; 95% CI: 2.4, 16.7; P ≤ .001) patients. No CAD at coronary CT angiography was associated with a low annualized MACE rate: 0.31% versus 2.06% with obstructive disease. CONCLUSION: Among individuals suspected of having CAD but without modifiable risk factors, CAD is common, with significantly increased hazards for MACE and mortality.

Missed opportunities for appropriate anticoagulation among emergency department patients with uncomplicated atrial fibrillation or flutter.

STUDY OBJECTIVE: Emergency department (ED) patients with atrial fibrillation or flutter are at risk of stroke, and guidelines recommend anticoagulation for patients with increased cardiovascular risk. Emergency physicians have a unique opportunity to provide appropriate anticoagulation for such patients, and we wished to investigate whether this was accomplished. METHODS: This retrospective cohort study used a database from 2 urban EDs to identify consecutive patients with an ED discharge diagnosis of atrial fibrillation or flutter from April 1, 2006, to March 31, 2010, who were managed solely by the emergency physician. Comorbidities, rhythms, and management were obtained by chart review, and complicated patients (those with an acute underlying medical condition) were excluded by predefined criteria. Patient medications on ED presentations were obtained through the provincial Pharmanet database. Patients were stratified into CHADS 2 (congestive heart failure, hypertension, age > 75, diabetes, stroke/transient ischemic attack) scores, and the primary outcome was the proportion of higher-risk (CHADS 2 score >0) patients who were discharged home with the incorrect anticoagulation by the emergency physician. The secondary outcome was the number of lower-risk (CHADS 2=0) patients who began receiving warfarin by the emergency physician orders. The regional ED database was interrogated to ascertain the number of patients who had a stroke at 30 days. RESULTS: Consecutive patients (1,090) were enrolled and 732 were discharged home with no cardiology consultation (657 fibrillation and 75 flutter). Of 151 higher-risk (CHADS 2 score >0) patients who should have been anticoagulated, 80 (53.0%; 95% confidence interval 44.7% to 61.0%) were discharged home from the ED without appropriate anticoagulation. In this group, 1 patient had an ischemic stroke at 24 days. Among 300 lower-risk patients (CHADS 2 score=0), 25 (8.3%; 95% confidence interval 5.6% to 12.2%) had warfarin initiated. CONCLUSION: In this cohort of ED patients with uncomplicated atrial fibrillation or flutter who were discharged without cardiology involvement, many were not appropriately anticoagulated before ED arrival, and more than half of such patients did not appear to have corrective measures initiated by the emergency physician. This may represent a potential opportunity to improve patient care and outcomes.

Antithrombotic therapies in Canadian atrial fibrillation patients with concomitant coronary artery disease: Insights from the CONNECT AF + PCI-II program.

BACKGROUND: Selecting the appropriate antithrombotic regimen for patients with atrial fibrillation (AF) who have undergone percutaneous coronary intervention (PCI) or have had medically managed acute coronary syndrome (ACS) remains complex. This multi-centre observational study evaluated patterns of antithrombotic therapies utilized among Canadian patients with AF post-PCI or ACS. METHODS AND RESULTS: By retrospective chart audit, 611 non-valvular AF patients [median (interquartile range) age 76 (69-83) years, CHADS2 score 2 (1-3)] who underwent PCI or had medically managed ACS between August 2018 and December 2020 were identified by 68 cardiologists across eight provinces in Canada. Overall, triple antithrombotic therapy [TAT: combined oral anticoagulation (OAC) and dual antiplatelet therapy (DAPT)] was the most common initial antithrombotic strategy, with use in 53.8 % of patients, followed by dual pathway therapy (32.7 % received OAC and a P2Y12 inhibitor, and 4.1 % received OAC and aspirin) and DAPT (9.3 %). Median duration of TAT was 30 (7, 30) days. Compared to the previous CONNECT AF + PCI-I program, there was an increased use of dual pathway therapy relative to TAT over time (P-value <.0001). DOACs (direct oral anticoagulants) represented 90.3 % of all OACs used overall, with apixaban being the most utilized (50.5 %). Proton pump inhibitors were used in 57.0 % of all patients, and 70.1 % of patients on ASA. Planned antithrombotic therapies at 1 year were: 76.2 % OAC monotherapy, 8.3 % OAC + ASA, 7.9 % OAC + P2Y12 inhibitor, 4.3 % DAPT, 1.3 % ASA alone, and <1 % triple therapy. CONCLUSION: In accordance with recent Canadian Cardiovascular Society guideline recommendations, we observed an increased use of dual pathway therapy relative to TAT over time in both AF patients post-PCI (elective and emergent) and in those with medically managed ACS. Additionally, DOACs have become the prevailing form of anticoagulation across all antithrombotic regimens. Our findings suggest that Canadian physicians are integrating evidence-based approaches to optimally manage the bleeding and thrombotic risks of AF patients post-PCI and/or ACS.

Thirty-day and 1-year outcomes of emergency department patients with atrial fibrillation and no acute underlying medical cause.

STUDY OBJECTIVE: Atrial fibrillation is the most common dysrhythmia observed in the emergency department (ED), yet there is little research describing long-term outcomes after ED management. Our objective is to describe ED treatment approach, conversion success rates, ED adverse events, and 30-day and 1-year outcomes for a cohort of ED patients with atrial fibrillation and no acute underlying medical cause. METHODS: This retrospective cohort study used a database from 2 urban EDs to identify consecutive patients with an ED discharge diagnosis of atrial fibrillation from April 1, 2006, to March 31, 2010. Comorbidities, rhythms, management, and immediate outcomes were obtained by manual chart review, and patients with an acute underlying medical condition were excluded by predefined criteria. Patients were stratified into 5 groups according to ED management: electrocardioversion, chemical cardioversion, spontaneous cardioversion, rate control only, and no arrhythmia-specific treatment. To identify deaths, strokes, and ED revisits within 1 year, each patient's unique provincial health number was linked to the provincial vital statistics registry and the regional ED database. Primary outcome was the number of patients having either stroke or death of any cause at 30 days, stratified by treatment group. RESULTS: Of 927 consecutive eligible patients, 121 (13.1%) converted to sinus rhythm before ED intervention, 357 (38.5%) received ED rhythm control, and 449 (48.4%) did not receive rhythm control. Overall, 142 of 927 patients (15.3%) were admitted to the hospital at the index ED visit. At 30 days, 2 patients had a stroke and 5 died (combined outcome rate 0.8%; 95% confidence interval 0.3% to 1.6%). All 7 of these patients were admitted at the index ED visit. CONCLUSION: In this large cohort of ED patients with atrial fibrillation and no acute underlying medical cause, the 30-day rate for stroke or death was less than 1%. Nearly 85% of patients-regardless of treatment approach or conversion to sinus rhythm-were discharged at the index ED visit, and none of these patients had a stroke or died at 30 days.

A prospective randomized controlled trial to assess the diagnostic performance of reduced tube voltage for coronary CT angiography.

OBJECTIVE: Tube voltage reduction has been shown to be an effective method to reduce radiation dose in nonobese patients undergoing coronary CT angiography. To date, the impact of reduced tube voltage on objective measures of diagnostic accuracy, as defined by quantitative coronary angiography (QCA), has not been established. The purpose of this article was to investigate the impact of tube voltage reduction on the diagnostic performance of coronary CTA compared with QCA. SUBJECTS AND METHODS: We performed a prospective randomized trial evaluating 50 consecutive patients referred for catheter angiography with a body mass index (BMI) ≤ 35 kg/m². Patients were randomly assigned to reduced (n = 24) or standard tube voltage (n = 26). Reduced tube voltage was defined as 80 or 100 kVp for individuals with BMI < 25 kg/m² or 25-35 kg/m², respectively; whereas standard tube voltage was defined as 100 or 120 kVp for individuals with BMI < 25 kg/m² or 25-35 kg/m², respectively. Tube current was fixed by study protocol as 600 mA (BMI < 30 kg/m²) or 650 mA (BMI ≥ 30 kg/m²). Coronary CTA examinations were interpreted by two blinded experienced readers with a third reader providing consensus. QCA was performed by an independent experienced core laboratory blinded to coronary CTA findings. Coronary artery segments were graded for stenosis as < 50%, 50-69%, and ≥ 70% by coronary CTA and as percentage stenosis by QCA. In an intention-to-diagnose fashion, all segments were included for final analysis, with nonevaluable segments by coronary CTA graded as obstructive. Signal and noise; contrast (mean signal-signal in left ventricular myocardium); and signal-to-noise ratio (SNR) and contrast-to-noise (CNR) ratio were compared. RESULTS: Mean age of the study cohort was 60.2 years; 78% were men. Prospective ECG gating was used in all patients, and no differences existed in scan length between groups (p = 0.19). Standard versus reduced tube voltage was associated with a reduction in effective radiation dose (2.6 ± 0.4 vs 1.3 ± 0.5 mSv, p < 0.001). The patient prevalence of luminal stenosis ≥ 50% was 56% (28/50). For detection of ≥ 50% stenosis in the standard versus reduced kVp groups, there were no differences in per-segment sensitivity (87% vs 84%, p = 0.73), specificity (92% vs 93%, p = 0.81), or accuracy (92% vs 91%, p = 0.70). No differences were noted for reduced versus standard tube current for SNR (13 ± 4 vs 13 ± 3, p = 0.59), CNR (10 ± 3 vs 10 ± 2, p = 0.99), or graded (0-4) image quality score (3.4 ± 0.8 vs 3.5 ± 0.6, p = 0.19). CONCLUSION: Compared with standard tube voltage, coronary CTA using reduced tube voltage results in lower effective radiation dose with comparable diagnostic performance.

Coronary CT angiography of patients with a normal body mass index using 80 kVp versus 100 kVp: a prospective, multicenter, multivendor randomized trial.

OBJECTIVE: We determined the effect of reduced 80-kVp tube voltage on the radiation dose and image quality of coronary CT angiography (CTA) in patients with a normal body mass index (BMI). SUBJECTS AND METHODS: A prospective, multicenter, multivendor trial was performed of 208 consecutive patients with a normal BMI (< 25 kg/m(2)) who had been referred for coronary CTA and did not have a history of coronary revascularization. Patients were randomized to 80-kVp imaging (n = 103) or 100-kVp imaging (n = 105). Three blinded readers graded interpretability and image quality. Study signal, noise, and contrast were also compared. RESULTS: Imaging with 80 kVp instead of 100 kVp was associated with 47% lower median radiation dose (median dose-length product, 62.0 mGy · cm [interquartile range, 54.0-123.3 mGy · cm] vs 117.0 mGy · cm [110.0-225.9 mGy · cm], respectively; 0.9 mSv [0.8-1.7 mSv] vs 1.6 mSv [1.4-3.2 mSv]; p < 0.001 for each) with no significant difference in interpretability (99% vs 99%; p = 0.99) or image quality (median score, 4.0 [interquartile range, 3.6-4.0] vs 4.0 [interquartile range, 3.8-4.0]; p = 0.20). Studies obtained using 80 kVp were associated with 27% increased signal (mean ± SD, 756 ± 157 vs 594 ± 105 HU; p < 0.001), 25% higher contrast (890 ± 156 vs 709 ± 108 HU; p < 0.001), and 50% greater noise (55 ± 15 vs 37 ± 12 HU; p < 0.001) with resultant 15% and 16% decreases in signal-to-noise (mean ± SD, 15 ± 5 vs 17 ± 5; p < 0.001) and contrast-to-noise (mean ± SD, 17 ± 6 vs 21 ± 5; p < 0.001) ratios, respectively. CONCLUSION: Coronary CTA using 80 kVp instead of 100 kVp was associated with a nearly 50% reduction in radiation dose with no significant difference in interpretability and noninferior image quality despite lower signal-to-noise and contrast-to-noise ratios. The use of 80-kVp tube voltage should be considered in dose-reduction strategies for coronary CTA of individuals with a normal BMI.

Emergency department management and 1-year outcomes of patients with atrial flutter.

STUDY OBJECTIVE: Atrial flutter is a common arrhythmia seen in the emergency department (ED), yet there is little research describing its management and outcomes. We analyze the success and safety of treatment of ED patients with atrial flutter. METHODS: This was a retrospective cohort study obtained by searching the ED administrative database of 2 urban hospitals to identify consecutive patients with a primary discharge diagnosis of atrial flutter from April 1, 2006, to January 31, 2009. We linked each patient's unique provincial health number to the provincial vital statistics registry and the regional ED database to identify subsequent deaths and strokes within 1 year. Manual chart review was conducted to confirm rhythms and outcomes and to identify patient comorbidities. Patients were stratified into 5 groups based on initial ED presentation and management approach: electrocardioversion, chemical cardioversion, spontaneous cardioversion, rate control only, and no acute ED arrhythmia-specific treatment. Primary outcome was the combined 1-year rate of stroke or death, and secondary outcomes included the proportion of eligible patients with conversion to normal sinus rhythm in each group and discharged to home. RESULTS: Data from 122 consecutive patients with a primary ED diagnosis of atrial flutter were collected; there were 3 deaths and no strokes (2.5%; 95% confidence interval 0% to 5.1%) in the following year. Patients undergoing electrocardioversion achieved normal sinus rhythm 91% of the time, with 93% discharged home; patients undergoing oral or intravenous antiarrhythmic treatment achieved sinus rhythm 27% of the time, with 60% discharged home. Discharge rates of patients with spontaneous cardioversion, rate control, and no ED treatment were 93%, 58%, and 96%, respectively. CONCLUSION: In this 2-center cohort of ED patients with atrial flutter, patients eligible for rhythm control had a higher success and lower admission rate with electrocardioversion than patients treated with antiarrhythmic medications. Overall, the majority of patients were discharged home. Deaths were typically related to concurrent medical illness rather than atrial flutter.

Effect of padding duration on radiation dose and image interpretation in prospectively ECG-triggered coronary CT angiography.

OBJECTIVE: Prospectively ECG-triggered coronary CT angiography images are acquired during a window in middiastole. Additional surrounding x-ray beam on time, or padding, can be variably set, and the increased padding results in additional available phases for analysis. The purpose of this study was to assess the effect of padding duration on image interpretability and its incident effect on radiation dose. SUBJECTS AND METHODS: We prospectively evaluated imaging of 886 patients undergoing consecutive prospectively ECG-triggered coronary CT angiographic examinations at three centers and compared the findings in patients stratified by padding duration. We assessed the effect of padding duration on image interpretability and radiation dose. RESULTS: The mean patient age was 56 +/- 12 years, and 58% of the patients were men. The median heart rate was 55 beats/min (interquartile range, 50-61 beats/min). Padding duration was 0, 1-99, and 100-150 milliseconds for 268, 482, and 136 patients, respectively, with no difference in image interpretability rate between groups (per patient, 98.8%, 97.3%, and 97.1%; per artery, 99.2%, 99.2%, and 99.1%). The groups differed in median radiation dose (2.3 mSv [interquartile range, 1.5-3.2 mSv]; 3.8 mSv [interquartile range, 2.3-4.7 mSv]; 5.5 mSv [interquartile range, 3.8-6.1 mSv]; p < 0.001). Independent of patient and scan parameters, increased padding was associated with greater radiation dose (45% increase per 100-millisecond increase in padding, p < 0.001). CONCLUSION: In a large multicenter study of coronary CT angiography of patients with excellent heart rate control, the use of minimal padding was associated with a substantial reduction in radiation dose with preserved image interpretability. Use of no or reduced padding should be considered in dose-reduction strategies.

Estimated radiation dose reduction using adaptive statistical iterative reconstruction in coronary CT angiography: the ERASIR study.

OBJECTIVE: The objective of our study was to assess the impact of Adaptive Statistical Iterative Reconstruction (ASIR) on radiation dose and study quality for coronary CT angiography (CTA). SUBJECTS AND METHODS: We prospectively evaluated 574 consecutive patients undergoing coronary CTA at three centers. Comparisons were performed between consecutive groups initially using filtered back projection (FBP) (n = 331) and subsequently ASIR (n = 243) with regard to patient and scan characteristics, radiation dose, and diagnostic study quality. RESULTS: There was no difference between groups in the use of prospective gating, tube voltage, or scan length. The examinations performed using ASIR had a lower median tube current than those obtained using FBP (median [interquartile range], 450 mA [350-600] vs 650 mA [531-750], respectively; p < 0.001). There was a 44% reduction in the median radiation dose between the FBP and ASIR cohorts (4.1 mSv [2.3-5.2] vs 2.3 mSv [1.9-3.5]; p < 0.001). After adjustment for scan settings, ASIR was associated with a 27% reduction in radiation dose compared with FBP (95% CI, 21-32%; p < 0.001). Despite the reduced current, ASIR was not associated with a difference in adjusted signal, noise, or signal-to-noise ratio (p = not significant). No differences existed between FBP and ASIR for interpretability per coronary artery (98.5% vs 99.3%, respectively; p = 0.12) or per patient (96.1% vs 97.1%, p = 0.65). CONCLUSION. ASIR enabled reduced tube current and lower radiation dose in comparison with FBP, with preserved signal, noise, and study interpretability, in a large multicenter cohort. ASIR represents a new technique to reduce radiation dose in coronary CTA studies.

Adaptive statistical iterative reconstruction: assessment of image noise and image quality in coronary CT angiography.

OBJECTIVE: The purpose of our study was to determine the effect of Adaptive Statistical Iterative Reconstruction (ASIR) on cardiac CT angiography (CTA) signal, noise, and image quality. MATERIALS AND METHODS: We evaluated 62 consecutive patients at three sites who underwent clinically indicated cardiac CTA using an ASIR-capable 64-MDCT scanner and a low-dose cardiac CTA technique. Studies were reconstructed using filtered back projection (FBP), ASIR-FBP composites using 20-80% ASIR, and 100% ASIR. The signal and noise were measured in the aortic root and each of the four coronary arteries. Two blinded readers graded image quality on a 5-point Likert scale and determined the proportion of interpretable segments. All segments were included for analysis regardless of size. RESULTS: In comparison with FBP (0% ASIR), the use of 20%, 40%, 60%, 80%, and 100% ASIR resulted in reduced image noise between groups (-7%, -17%, -26%, -35%, and -43%, respectively; p < 0.001) without difference in signal (p = 0.60). There were significant differences between groups (0%, 20%, 40%, 60%, 80%, and 100% ASIR) in the Likert scores (1.5, 2.1, 3.7, 3.8, 2.0, and 1.1, respectively; p < 0.001) and proportion of interpretable segments (88.7%, 89.3%, 90.5%, 90.4%, 88.0%, and 87.3%, respectively; p < 0.001). Reconstruction using 40% and 60% ASIR had the highest Likert scores and largest proportion of interpretable segments. In comparison with FBP, each was associated with higher Likert scores and increased interpretable segments (p < 0.001 for all). CONCLUSION: ASIR resulted in noise reduction and significantly impacted image quality. When using a low tube current technique, cardiac CTA reconstruction using 40% or 60% ASIR significantly improved image quality and the proportion of interpretable segments compared with FBP reconstruction.

Establishing reference ranges for ambulatory electrocardiography parameters: meta-analysis.

OBJECTIVE: Despite the widespread and increasing use of ambulatory electrocardiography (ECG), there is no consensus on reference ranges for ambulatory electrocardiogram parameters to guide interpretation. We sought to determine population distribution-based reference ranges for parameters measured during ambulatory electrocardiogram in healthy adults, based on existing literature. METHODS: We searched multiple databases from 1950 to 2020. Articles reporting original data from ≥24-hour ambulatory electrocardiogram monitoring in healthy adults were included. Data extraction and synthesis were performed according to Meta-analysis of Observational Studies in Epidemiology guidelines. The prevalence/mean and SD for common parameters (sinus pauses, conduction abnormalities and ectopy) were extracted by age group (18-39, 40-59, 60-79 and 80+ years). RESULTS: We identified 33 studies involving 6466 patients. Sinus pauses of >3 s were rare (pooled prevalence <1%) across all ages. Supraventricular ectopy of >1000/24 hours increased with age, from 0% (95% CI 0% to 0%) in those aged 18-39 years to 6% (95% CI 0% to 17%) in those aged 60-79 years. Episodes of supraventricular tachycardia increased from 3% (95% CI 1% to 6%) in those aged 18-39 years to 28% (95% CI 9% to 52%) in those aged 60-79 years. Ventricular ectopy of >1000/24 hours also increased with age, from 1% (95% CI 0% to 2%) in those aged 18-39 years to 5% (95% CI 1% to 10%) in those aged 60-79 years. Episodes of non-sustained ventricular tachycardia ranged from 0% (95% CI 0% to 1%) in those aged 18-39 years to 2% (95% CI 0% to 5%) in those aged 60-79 years. CONCLUSION: Despite the limitations of existing published data, this meta-analysis provides evidence-based reference ranges for ambulatory electrocardiogram parameters and highlights significant age-dependent differences that should be taken into account during interpretation.

Association Between Patient and Physician Sex and Physician-Estimated Stroke and Bleeding Risks in Atrial Fibrillation.

BACKGROUND: Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain. METHODS: We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male). RESULTS: Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians. CONCLUSIONS: Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation.

Assessment of cardiovascular risk and preparticipation screening protocols in masters athletes: the Masters Athlete Screening Study (MASS): a cross-sectional study.

BACKGROUND: Underlying coronary artery disease (CAD) is the primary cause of sudden cardiac death in masters athletes (>35 years). Preparticipation screening may detect cardiovascular disease; however, the optimal screening method is undefined in this population. The Physical Activity Readiness Questionnaire for Everyone (PAR-Q+) and the American Heart Association (AHA) Preparticipation Screening Questionnaire are often currently used; however, a more comprehensive risk assessment may be required. We sought to ascertain the cardiovascular risk and to assess the effectiveness of screening tools in masters athletes. METHODS: This cross-sectional study performed preparticipation screening on masters athletes, which included an ECG, the AHA 14-element recommendations and Framingham Risk Score (FRS). If the preparticipation screening was abnormal, further evaluations were performed. The effectiveness of the screening tools was determined by their positive predictive value (PPV). RESULTS: 798 athletes were included in the preparticipation screening analysis (62.7% male, 54.6±9.5 years, range 35-81). The metabolic equivalent task hours per week was 80.8±44.0, and the average physical activity experience was 35.1±14.8 years. Sixty-four per cent underwent additional evaluations. Cardiovascular disease was detected in 11.4%, with CAD (7.9%) being the most common diagnosis. High FRS (>20%) was seen in 8.5% of the study population. Ten athletes were diagnosed with significant CAD; 90% were asymptomatic. A high FRS was most indicative of underlying CAD (PPV 38.2%). CONCLUSION: Masters athletes are not immune to elevated cardiovascular risk and cardiovascular disease. Comprehensive preparticipation screening including an ECG and FRS can detect cardiovascular disease. An exercise stress test should be considered in those with risk factors, regardless of fitness level.

Implementation of an emergency department atrial fibrillation and flutter pathway improves rates of appropriate anticoagulation, reduces length of stay and thirty-day revisit rates for congestive heart failure.

OBJECTIVES: An evidence-based emergency department (ED) atrial fibrillation and flutter (AFF) pathway was developed to improve care. The primary objective was to measure rates of new anticoagulation (AC) on ED discharge for AFF patients who were not AC correctly upon presentation. METHODS: This is a pre-post evaluation from April to December 2013 measuring the impact of our pathway on rates of new AC and other performance measures in patients with uncomplicated AFF solely managed by emergency physicians. A standardized chart review identified demographics, comorbidities, and ED treatments. The primary outcome was the rate of new AC. Secondary outcomes were ED length of stay (LOS), referrals to AFF clinic, ED revisit rates, and 30-day rates of return visits for congestive heart failure (CHF), stroke, major bleeding, and death. RESULTS: ED AFF patients totalling 301 (129 pre-pathway [PRE]; 172 post-pathway [POST]) were included; baseline demographics were similar between groups. The rates of AC at ED presentation were 18.6% (PRE) and 19.7% (POST). The rates of new AC on ED discharge were 48.6 % PRE (95% confidence interval [CI] 42.1%-55.1%) and 70.2% POST (62.1%-78.3%) (20.6% [p<0.01; 15.1-26.3]). Median ED LOS decreased from 262 to 218 minutes (44 minutes [p<0.03; 36.2-51.8]). Thirty-day rates of ED revisits for CHF decreased from 13.2% to 2.3% (10.9%; p<0.01; 8.1%-13.7%), and rates of other measures were similar. CONCLUSIONS: The evidence-based pathway led to an improvement in the rate of patients with new AC upon discharge, a reduction in ED LOS, and decreased revisit rates for CHF.

Detecting Underlying Cardiovascular Disease in Young Competitive Athletes.

BACKGROUND: Sudden cardiac death (SCD) is frequently the first manifestation of underlying cardiovascular disease in young competitive athletes (YCAs), yet there are no Canadian guidelines for preparticipation screening in this population. The goal of this study was to determine the prevalence of potentially lethal cardiovascular disease in a sample of Canadian YCAs by comparing 2 screening strategies. METHODS: We prospectively screened 1419 YCAs in British Columbia, Canada (age 12-35 years). We initially screened 714 YCAs using the American Heart Association 12-element recommendations, physical examination, and electrocardiogram (ECG) examination (phase 1). This strategy yielded a high number of false positive results; 705 YCAs were subsequently screened using a novel SportsCardiologyBC (SCBC) questionnaire and ECG examination in the absence of a physical examination (phase 2). RESULTS: Overall, 7 YCAs (0.52%) were found to have clinically significant diagnoses associated with SCD (4 pre-excitation, 1 long QT syndrome, 1 mitral valve prolapse, 1 hypertrophic cardiomyopathy). Six of the 7 athletes (85.7%) with disease possessed an abnormal ECG. Conversely, only 2 had a positive personal or family history (1 athlete had an abnormal ECG and family history). The SCBC questionnaire and protocol (phase 2) was associated with fewer false positive screens; 3.7% (25 of 679) compared with 8.1% (55 of 680) in phase 1 (P = 0.0012). CONCLUSIONS: The prevalence of conditions associated with SCD in a cohort of Canadian YCAs was comparable with American and European populations. The SCBC questionnaire and protocol were associated with fewer false positive screens. The ECG identified most of the positive cases irrespective of screening strategy used.

Use of Evidence-Based Therapy for Cardiovascular Risk Factors in Canadian Outpatients With Atrial Fibrillation: From the Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation (FREEDOM AF) and Co-ordinated National Network to Engage Physicians in the Care and Treatment of Patients With Atrial Fibrillation (CONNECT AF).

Using data collected from 2 national atrial fibrillation (AF) primary care physician chart audits (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation [FREEDOM AF] and Co-ordinated National Network to Engage Physicians in the Care and Treatment of Patients With Atrial Fibrillation [CONNECT AF]), we evaluated the frequency of, and factors associated with, the use of cardiovascular (CV) evidence-based therapies in Canadian AF outpatients with at least 1 CV risk factor or co-morbidity. Of the 11,264 patients enrolled, 9,495 (84.3%) were eligible for one or more CV evidence-based therapies. The proportions of patients with AF receiving all eligible guideline-recommended therapies were 40.8% of patients with coronary artery disease, 48.9% of patients with diabetes mellitus, 40.2% of patients with heart failure, 96.7% of patients with hypertension, and 55.1% of patients with peripheral arterial disease. Factors that were independently associated with nonreceipt of all indicated evidence-based therapies included sinus rhythm rather than AF at baseline and liver disease. In conclusion, although most Canadian outpatients with AF have CV risk factors or co-morbidities, a substantial portion of these patients did not receive all guideline-recommended therapies. These findings suggest that there is an opportunity to improve the quality of care for patients with AF in Canada.

Comparison of Rates of Coronary Angiography and Combined Testing Procedures in Patients Seen in the Emergency Room With Chest Pain (But No Objective Acute Coronary Syndrome Findings) Having Coronary Computed Tomography Versus Exercise Stress Testing.

Coronary computed tomography angiography (CCTA) appears comparable to standard care, including exercise stress testing (EST), in diagnosing acute coronary syndrome in emergency department (ED) patients with chest pain but may increase downstream testing. The objective of this study was to investigate rates of post-CCTA versus post-EST testing for (1) invasive angiography and (2) all combined cardiac testing. This was a retrospective cohort study performed at 2 urban Canadian EDs involving patients aged up to 65 years with chest pain but no objective ACS findings that were evaluated with CCTA or EST at the physician's discretion. The primary outcome was the proportion of patients who had 30-day invasive angiography in each group; secondary outcomes included all subsequent 30-day cardiac testing, including nuclear medicine scanning. From July 1, 2012, to June 30, 2014, we collected 1,700 patients: 521 CCTA and 1,179 EST. Demographics and risk factors were similar in both cohorts. In the following 30 days, 30 CCTA (5.8%) and 297 EST (25.2%) patients underwent any type of additional cardiac testing (difference 19.4%, 95% CI 16.0 to 22.6), whereas 12 CCTA (2.3%) and 20 EST patients (1.7%) underwent angiography (difference 0.6%, 95% CI -0.8% to 2.6%). No patients in either group died or had a myocardial infarction within 30 days. For ED patients with chest pain who underwent brief observation, CCTA and EST had similar 30-day angiography rates, but CCTA patients underwent significantly less overall cardiac investigations.

There Are Sex Differences in the Demographics and Risk Profiles of Emergency Department (ED) Patients With Atrial Fibrillation and Flutter, but no Apparent Differences in ED Management or Outcomes.

OBJECTIVES: In non-emergency department (ED) settings, women with atrial fibrillation and flutter (AFF) have different presentations, treatments, and outcomes than men: they are older, less likely to be treated with rhythm control strategies or appropriate anticoagulation, and more likely to have strokes. This has not been investigated in ED patients. METHODS: Records from consecutive ED patients from January 1 to December 31, 2009, with electrocardiogram-proven AFF at two urban hospitals were collected. Review of administrative and clinical data identified patient demographics, clinical characteristics, comorbidities, and ED treatments. The regional ED database was queried to determine 30-day and 1-year follow-up visits, and the provincial vital statistics database was referenced to obtain 30-day and 1-year mortality; all outcomes were stratified by sex. The primary outcome, which reflected overall appropriateness of ED care, was the proportion of patients who were discharged home at their index ED visits, who then had unscheduled 30-day ED revisits. Secondary outcomes included the proportion of eligible patients who underwent acute rhythm control strategies and the proportion of high-risk patients who had previously inadequately anticoagulation strategies corrected by the emergency physician. Additional outcomes included the ED length of stay (LOS) and 30-day and 1-year rates of stroke and death. RESULTS: A total of 1,112 records were reviewed: 470 women (42.3%) and 642 men. Women were a median 8 years (interquartile range = 3 to 13 years) older than men, had higher rates of cardiovascular comorbidities, and were more likely to present with atypical symptoms such as weakness or dyspnea. On their index ED visits, 50.2% of women and 41.3% of men were admitted. At 30 days, 39 of 234 (16.7%) women and 55 of 377 (14.6%) men who were discharged at their index ED visits had made revisits, for a risk difference of 2.1% (95% confidence interval = -3.9% to 8.5%). There were no apparent sex differences in the use of acute rhythm control or in the appropriateness of anticoagulation decisions. ED LOS was similar between women and men, as were 30-day and 1-year stroke or death rates. CONCLUSIONS: Female ED AFF patients were older, had more comorbidities, and were more likely to be admitted. However, the overall management and outcomes, including 30-day revisits, appeared to be similar to that of males, indicating that there appeared to be little sex-based discrepancy in ED care and outcomes.