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Globally, vascular diseases are a leading cause of morbidity and mortality. Many of the most significant risk factors for vascular disease have a gendered dimension, and sex differences in vascular diseases incidence are apparent, worldwide. In this narrative review, we provide a contemporary picture of sex- and gender-related determinants of vascular disease. We illustrate key factors underlying sex-specific risk stratification, consider similarities and sex differences in vascular disease risk and outcomes with comparisons of data from the global North (ie, developed high-income countries in the Northern hemisphere and Australia) and the global South (ie, regions outside Europe and North America), and explore the relationship between country-level gendered inequities in vascular disease risk and the United Nation's gender inequality index. Review findings suggest that the rising incidence of vascular disease in women is partly explained by an increase in the prevalence of traditional risk factors linked to gender-related determinants such as shifting roles and relations related to the double burden of employment and caregiving responsibilities, lower educational attainment, lower socioeconomic status, and higher psychosocial stress. Social isolation partly explained the higher incidence of vascular disease in men. These patterns were apparent across the global North and South. Study findings emphasize the necessity of taking into account sex differences and gender-related factors in the determination of the vascular disease risk profiles and management strategies. As we move toward the era of precision medicine, future research is needed that identifies, validates, and measures gender-related determinants and risk factors in the global South., (Copyright © 2022 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: Atrial fibrillation (AF) is the most common arrhythmia in men and women worldwide, and its prevalence is increasing. Management of AF is guided by evidence-based clinical practice guidelines which provide recommendations based on available evidence. The extent of sex-specific data in the AF literature used to provide guideline recommendations has not been investigated. Therefore, using the 2020 Canadian Cardiovascular Society (CCS) AF management guidelines as an example, the purpose of this study was to review female representation and the reporting of sex-disaggregated data in the studies referenced in AF guidelines., Methods: Randomised controlled trials (RCTs) and prospective and retrospective cohorts were screened to calculate the proportion of study participants who were female and to establish whether studies provided sex-disaggregated analyses. The participant-prevalence ratio (PPR), a quotient of the female participant rate and the prevalence of women in the AF population, was calculated for each study., Results: A total of 885 studies included in the CCS guidelines were considered. Of those, 467 met the inclusion criteria. Overall, women represented 39.1% of the population over all of the studies and RCTs had the lowest proportions of women (33.8%, PPR 0.70). Of studies with sex-disaggregated analyses (n = 140; 29.9%), single-centre RCTs and retrospective cohorts had the lowest and highest rates of sex-specific analyses, respectively (11.5% and 32.5%)., Conclusions: The evidence used to derive guideline recommendations may be inadequate for sex-specific recommendations. Until enough data can support women-specific guidelines, increased inclusion of females in AF studies, may aid in the precision of recommendations., (Copyright © 2022 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: Evidence differentiating the effect of biological sex from psychosociocultural factors (gender) in different societies and its relation to cardiovascular diseases is scarce. We explored the association between sex, gender, and cardiovascular health (CVH) among Canadian (CAN) and Austrian (AT) populations., Methods: The Canadian Community Health Survey (CCHS) (n = 63,522; 55% female) and Austrian Health Interview Survey (AT-HIS) (n = 15,771; 56% female) were analyzed in a cross-sectional survey design. The CANHEART/ATHEART index, a measure of ideal CVH composed of 6 cardiometabolic risk factors (smoking, physical activity, fruit and vegetable consumption, overweight/obesity, diabetes, and hypertension; range 0-6; higher scores reflecting better CVH) was calculated for both databases. A composite measure of psychosociocultural gender was computed for each country (range 0-1, higher score identifying characteristics traditionally ascribed to women)., Results: Median CANHEART 4 (interquartile range 3-5) and CAN gender scores 0.55 (0.49-0.60) were similar to median ATHEART 4 (3-5) and AT gender scores 0.55 (0.46-0.64). Although higher gender scores (CCHS: β = -1.33, 95% confidence interval [CI] -1.44 to -1.22; AT-HIS: β = -1.08, 95% CI -1.26 to -0.89)) were associated with worse CVH, female sex (CCHS: β = 0.35, 95% CI (0.33-0.37); AT-HIS: β = 0.60, 95% CI (0.55-0.64)) was associated with better CVH in both populations. In addition, higher gender scores were associated with increased prevalence of heart disease compared with female sex. The magnitude of this risk was higher in Austrians., Conclusions: These results demonstrate that individuals with characteristics typically ascribed to women reported poorer cardiovascular health and higher risk of heart disease, independently from biological sex and baseline CV risk factors, in both countries. Female sex exhibited better CV health and a lower prevalence of heart disease than male in both populations. However, gender factors and magnitude of gender impact varied by country., (Copyright © 2021 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Numerous studies have demonstrated that sex (a biological variable) and gender (a psychosocial construct) impact health and have discussed the mechanisms that may explain these relationships. Funding agencies have called for all health researchers to incorporate sex and gender into their studies; however, the way forward has been unclear to many, particularly due to the varied definition of gender. We argue that just as there is no standardized definition of gender, there can be no standardized measurement thereof. However, numerous measurable gender-related variables may influence individual or population-level health through various pathways. The initial question should guide the selection of specific gender-related variables based on their relevance to the study, to prospectively incorporate gender into research. We outline various methods to provide clarification on how to incorporate gender into the design of prospective clinical and epidemiological studies as well as methods for statistical analysis., (Copyright © 2020 Elsevier Inc. All rights reserved.)

New knowledge about male-female differences in pathophysiology, diagnosis, and treatment is shifting the practice of medicine from a one-size-fits all approach to a more individualized process that considers sex-specific interventions at the point of care. In this article, we review how clinical practice guideline committees can incorporate a structured framework to determine whether sex-specific assessments of the quality of the evidence or the particular recommendations should be made. The process can be operationalized by societies who author clinical practice guidelines by developing formal policies to approach biological sex in a systematic way, and by ensuring that writing committees include an individual who will champion the formal appraisal of the literature for associations between sex and the outcomes of interest. Ongoing challenges are discussed, and solutions are provided for how to disaggregate the evidence, how to assess bias, how to improve search strategies, and what to do when the data are insufficient to make sex-specific recommendations. Application of sex-specific recommendations will involve routinely asking whether the presentation, diagnostic workup, or management might change for each patient if they were the opposite sex., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Rapid reperfusion of the infarct-related artery is the cornerstone of therapy for the management of acute ST-elevation myocardial infarction (STEMI). Canada's geography presents unique challenges for timely delivery of reperfusion therapy for STEMI patients. The Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology STEMI guideline was developed to provide advice regarding the optimal acute management of STEMI patients irrespective of where they are initially identified: in the field, at a non-percutaneous coronary intervention-capable centre or at a percutaneous coronary intervention-capable centre. We had also planned to evaluate and incorporate sex and gender considerations in the development of our recommendations. Unfortunately, inadequate enrollment of women in randomized trials, lack of publication of main outcomes stratified according to sex, and lack of inclusion of gender as a study variable in the available literature limited the feasibility of such an approach. The Grading Recommendations, Assessment, Development, and Evaluation system was used to develop specific evidence-based recommendations for the early identification of STEMI patients, practical aspects of patient transport, regional reperfusion decision-making, adjunctive prehospital interventions (oxygen, opioids, antiplatelet therapy), and procedural aspects of mechanical reperfusion (access site, thrombectomy, antithrombotic therapy, extent of revascularization). Emphasis is placed on integrating these recommendations as part of an organized regional network of STEMI care and the development of appropriate reperfusion and transportation pathways for any given region. It is anticipated that these guidelines will serve as a practical template to develop systems of care capable of providing optimal treatment for a wide range of STEMI patients., (Copyright © 2018 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: Cardiac surgery waitlist recommendations, which were developed based on expert opinion, poorly predict preoperative mortality. Studies reporting risk factors for waitlist mortality have not evaluated the risks including nonadherence to waitlist benchmarks., Methods: In patients who underwent cardiac surgery or died on the waitlist between 2005 and 2015, we used a Fine and Gray competing risk model to identify independent predictors of waitlist mortality in 12,106 patients scheduled for urgent, semiurgent, or nonurgent surgery. The predictive variables were compared with Canadian Cardiovascular Society (CCS) waitlist recommendations using the Akaike information criterion., Results: A total of 101 (0.8%) patients died awaiting surgery. The median wait times and frequency waitlist deaths among emergent, urgent, semi-urgent, and nonurgent surgery were 0.6, 7.4, 69.0, 55.5 days (P < 0.001) and 6.3%, 0.8%, 0.3%, 0.6% (P < 0.001), respectively. Adherence to CCS waitlist recommendations was higher in patients who died on the waitlist (51.6% vs 70.8%, P = 0.001) and was not predictive of waitlist mortality (hazard ratio 1.48, 95% confidence interval 0.62-0.56). Independent predictors of waitlist mortality were age, aortic surgery, ejection fraction < 35%, urgent surgery, prior myocardial infarction, haemodynamic instability during cardiac catheterization, hypertension, and dyslipidemia. These variables were superior to current CCS guidelines (Akaike information criterion 1251 vs 1317, likelihood ratio test P < 0.001)., Conclusions: CCS waitlist recommendations were poorly predictive of waitlist mortality and the majority of waitlist deaths occur within recommended benchmarks. We identified variables associated with waitlist mortality with improved clinical performance. Our findings suggest a need to re-evaluate cardiac surgical triage criteria using evidence-based data., (Copyright © 2018 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: We examined variation in hospital treatment and its relationship to clinical outcome in a large population-based cohort of ACS patients within a single payer-government funded health care system., Methods: Patients hospitalized in 106 hospitals in Alberta, Canada with a primary diagnosis of ACS were included (July 1, 2010-March 31, 2013) with comparisons made across the three cardiac catheterization-capable hospitals (Sites A-C). Cox proportional-hazard regression models were used to examine the multivariable-adjusted association between site and 1-year death or repeat cardiovascular (CV) hospitalization (primary endpoint)., Results: Of 14,155 patients, 1938 (13.7%) were admitted to a community hospital without transfer to an invasive hospital (10.7% in-hospital death). The remaining were admitted (n=4514, 36.9%) or transferred (n=7703, 63.1%) to an invasive hospital (A:5480; B:3621; C:3116) where 11,247 (92.1%) underwent catheterization. Comorbidities and angiographic disease burden differed across sites. Variation in 30-day revascularization (PCI: 71.3%, 72.0%, 68.7%, p<0.001; CABG: 6.2%, 6.4%, 9.3%, p<0.001) and drug-eluting stent use for PCI (24.3%, 54.6%, 50.5%, p<0.001) were observed. After adjustment for patient demographics and comorbidities, variation in rates of 1-year death or CV hospitalization was observed among those with 30-day revascularization (p(interaction)<0.001; B versus A: HR 0.78, 95%CI 0.66-0.91; C versus A: HR 0.77, 95%CI 0.65-0.91; B versus C: HR 1.01, 95%CI 0.84-1.21)., Conclusions: Despite a government funded health system, we have shown variation in hospital treatment exists. Following adjustment hospital site was associated with differences in clinical outcome within 1year. Hence, further efforts may be warranted to help address potential disparities in ACS care., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: Unequivocally, cardiac rehabilitation (CR) in patients with established cardiovascular disease improves survival. However, its effect on higher-risk ethnic groups has not been explored. Accordingly, we evaluated the effect of CR on South Asian (SA) compared with European Canadians with coronary artery disease (CAD)., Methods: Using the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) registry, 26,167 patients from Edmonton, Alberta who received coronary angiography with documented CAD were reviewed (January 2002 to March 2012). After excluding Chinese patients, 1027 SA patients were compared with 11,992 European Canadian patients using validated surname algorithms. Adjustment was performed using a Cox proportional hazard model., Results: Of the SA cohort, 50.6% attended CR, compared with 43.0% of the European Canadian cohort (P < 0.001). After adjustment, CR was associated with long-term survival irrespective of ethnic group (total study population: hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.52-0.63; P < 0.001; SA population: HR, 0.63; 95% CI, 0.40-0.99; P = 0.045; European population: HR, 0.57; 95% CI, 0.52-0.63; P < 0.001). When comparing SA vs European Canadians attending CR, improved survival was observed in SA patients (HR, 0.58; 95% CI, 0.40-0.85; P < 0.001). This benefit appeared limited to SA patients who completed CR (complete CR: HR, 0.37; 95% CI, 0.17-0.85; P = 0.02; incomplete CR: HR, 0.78; 95% CI, 0.45-1.35; P = 0.38)., Conclusions: Overall, referral rates to CR remains low but attendance appears higher in SA patients. Among those who attended CR, there is a strong association with improved survival irrespective of ethnic status. In SA patients with CAD, attendance and completion of CR should be strongly endorsed because of its incremental benefit., (Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

The Canadian Cardiovascular Society (CCS) is implementing the Canadian Heart Health Strategy and Action Plan recommendation to build knowledge infrastructure, through its Data Definitions and Quality Indicator (QI) project. The CCS selected cardiac rehabilitation (CR) and secondary prevention as a content area for QI development. In accordance with the CCS QI Best Practice Methodology, rapid reviews of the literature were conducted. A long list of 37 QIs, in the areas of structure, process, and outcome were developed. Through an online survey, 26 (42%) of all contacted external experts rated each QI on importance, scientific acceptability, and feasibility, using a 7-point scale. The overall mean rating was 5.4 ± 1.4. Through a consensus process, the working group excluded 8 QIs based on this feedback, and several others were revised. A 30-day Web consultation was then undertaken, to solicit input from the broader CCS and CR community. A "top 5" list of QIs was requested by the CCS, which were: (1) inpatients referred to CR; (2) wait times from referral to CR enrollment; (3) patient self-management education; (4) increase in exercise capacity; and (5) emergency response strategy. Knowledge translation activities are now under way to promote utilization of the QIs and ultimately improve CR care., (Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: There is a known association between a depressed left ventricular ejection fraction (LVEF < 0.35) and increased mortality in patients undergoing coronary artery bypass graft (CABG) operations. Recent studies show that elevated preoperative LV end-diastolic pressure (LVEDP) is an independent predictor of operative death for patients undergoing CABG. Therefore, the purpose of this study was to define the long-term predictive value of elevated LVEDP in CABG and its relationship to LVEF., Methods: Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH), a clinical data collection initiative capturing all patients undergoing isolated CABG in Alberta, Canada, was used to identify 6,735 consecutive patients who had LVEDP and LVEF data recorded by catheterization undergoing isolated CABG between 1996 and 2011. Patients were divided into four groups based on LVEF and LVEDP: group 1 (LVEF≥0.35, LVEDP<18 mm Hg), group 2 (LVEF<0.35, LVEDP<18 mm Hg), group 3 (LVEF≥0.35, LVEDP≥18 mm Hg), and group 4 (LVEF<0.35, LVEDP≥18 mm Hg)., Results: Patients with an LVEF>0.35 had improved long-term survival compared with patients with depressed LVEF (LVEF<0.35, p<0.001). In patients with a depressed LVEF, an elevated LVEDP was associated with decreased long-term survival (group 2 vs 4, p<0.001). Other significant independent predictors for death were age, chronic obstructive pulmonary disease, peripheral vascular disease, dialysis dependence, and congestive heart failure (p<0.001). Isolated elevated LVEDP was not an independent risk factor for long-term mortality., Conclusions: In patients with a depressed LVEF, an elevated LVEDP is associated with poor long-term survival. These data support the added value of long-term prognostic value of LVEDP in patients with depressed LVEF undergoing CABG., (Copyright © 2014. Published by Elsevier Inc.)

Background: The efficacy of coronary artery bypass graft surgery (CABG) and percutaneous coronary intervention (PCI) in patients with coronary artery disease has been well defined by randomized controlled trials. However, patients with severe left ventricular dysfunction (ejection fraction <35%) were underrepresented in these trials, and management of these complex patients remains unclear. The purpose of this study was to compare the outcomes of patients with coronary artery disease and left ventricular dysfunction undergoing CABG versus PCI., Methods: The Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH), a clinical data collection and outcome monitoring initiative for the province of Alberta, Canada, was used to identify 2925 patients with coronary artery disease and left ventricular dysfunction undergoing CABG (n = 1,326) or PCI (n = 1,599) between 1995 and 2008. Patients were propensity matched to obtain comparable subgroups among left ventricular dysfunction patients., Results: Cox proportional hazard analysis of the propensity-matched subgroups identified that CABG was significantly associated with lower rates of repeat revascularization and better survival compared with PCI at 1, 5, 10, and 15 years. Other significant independent predictors of poor long-term survival included age, renal failure, heart failure, diabetes mellitus, peripheral vascular disease, prior myocardial infarction, left main coronary artery disease, and prior CABG., Conclusions: For patients with coronary artery disease and left ventricular dysfunction, CABG was associated with lower rates of repeat revascularization and improved survival over PCI, after adjustment for baseline risk profile differences. Further research exploring the factors leading to use of a particular revascularization modality in this patient population is required., (Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Frailty is superior to chronological age as a predictor of outcome. The Edmonton Frail Scale (EFS) is a simple valid measure of frailty, covering multiple important domains, with scores ranging from 0 (not frail) to 17 (very frail). The purpose of this pilot study was to assess the EFS in a group of elderly patients with acute coronary syndrome (ACS)., Methods: The EFS was administered to 183 consecutive patients with ACS aged ≥ 65 years admitted to a single centre in Edmonton, Alberta, Canada., Results: Scores ranged from 0-13. Patients with higher EFS scores were older, with more comorbidities, longer lengths of stay (EFS 0-3: mean, 7.0 days; EFS 4-6: mean, 9.7 days; and EFS ≥ 7: mean, 12.7 days; P = 0.03), and decreased procedure use. Crude mortality rates at 1 year were 1.6% for EFS 0-3, 7.7% for EFS 4-6, and 12.7% for EFS ≥ 7 (P = 0.05). After adjusting for baseline risk differences using a "burden of illness" score, the hazard ratio for mortality for EFS ≥ 7 compared with EFS 0-3 was 3.49 (95% confidence interval [CI], 1.08-7.61; P = 0.002)., Conclusions: The EFS is associated with increased comorbidity, longer lengths of stay, and decreased procedure use. After adjustment for burden of illness, the highest frailty category is independently associated with mortality in elderly patients with ACS. Further work is needed to determine whether the use of a validated frailty instrument would better delineate medical decision making in this important, often disadvantaged population., (Copyright © 2013 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: Marked variation exists concerning the utilization of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG). The objective of this study was to examine differences in predictors of mode of revascularization across 3 provincial jurisdictions., Methods: All patients who underwent PCI and isolated CABG in British Columbia, Alberta, and Nova Scotia between 1996 and 2007 were considered. Age- and sex-standardized rates of PCI and CABG per 100,000 population and PCI to CABG ratios were calculated by year and province. Logistic regression models were constructed to identify independent predictors of mode of revascularization in each province., Results: A total of 32,190 and 69,409 patients underwent CABG and PCI, respectively, during the study period. Significant increases in the age- and sex-adjusted PCI to CABG ratios were observed in all 3 provinces, but these ratios differed between provinces. Across all 3 jurisdictions, female sex and diagnosis of acute coronary syndrome favoured increased PCI vs CABG, and increased age, left main, or 3-vessel disease occurring before myocardial infarction, and diabetes favoured lower PCI vs CABG. After adjusting for clinical and angiographic factors, there remained a significant variation in choice of PCI vs CABG between the 3 provinces over time., Conclusions: Significant interprovincial variability in PCI to CABG ratios was observed. Though certain patient-related factors predictive of either PCI or CABG were identified, factors beyond clinical presentation played a role in the choice of revascularization approach., (Copyright © 2013 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: Although bilateral internal thoracic artery (BITA) grafting in coronary artery bypass grafting (CABG) is associated with low morbidity and good long-term results, controversy exists about the age after which BITA grafting is no longer beneficial. We sought to determine if such an age cutoff point exists., Methods: The study cohort consisted of 5,601 consecutive patients from a cardiac surgery registry who underwent isolated CABG (1,038 [19%] BITA grafts, 4,029 [72%] single internal thoracic artery [SITA] grafts, 534 [10%] vein-only grafts) between 1995 and 2008. A Cox model was used to compare survival by use of bilateral, single, or no internal thoracic artery (ITA) grafts, adjusting for baseline clinical and demographic characteristics., Results: Mean follow-up was 7.1 years. Patients undergoing BITA grafting had the lowest 1-year mortality (2.4% versus 4.3% SITA grafting and 8.2% vein-only grafting; p < 0.0001). Relative to SITA grafting, a crude survival benefit of 54% existed for BITA grafting (hazard ratio [HR] 0.46; 95% confidence interval [CI], 0.37 to 0.57; p < 0.0001) with worse survival for vein-only grafts (HR, 1.16; 95% CI, 0.99 to 1.37; p = 0.07). After adjustment, the benefit of BITA grafting was no longer statistically significant (HR, 0.87; 95% CI, 0.69 to 1.08; p = 0.2). However age may be an effect modifier: a spline analysis plotting HR (BITA grafting versus SITA grafting) against age suggested a potential survival advantage associated with BITA grafting in patients younger than 69.9 years., Conclusions: Bilateral internal thoracic artery grafting is a reasonable revascularization strategy in suitable patients up to age 70 years. As benefits of arterial grafting become more obvious over time, a longer period of follow-up will be needed to confirm the advantage of a BITA grafting strategy. In the meantime the BITA grafting advantage for patients older than 70 years is not clear., (Copyright © 2011 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: The clinical correlates of coronary collaterals and the effects of coronary collaterals on prognosis are incompletely understood., Methods: We performed a study of 55,751 patients undergoing coronary angiography to evaluate the correlates of angiographically apparent coronary collaterals, and to evaluate their association with survival., Results: The characteristic most strongly associated with the presence of collaterals was a coronary occlusion (odds ratio [OR], 28.9; 95% confidence interval [CI], 27.1-30.6). Collaterals were associated with improved adjusted survival overall (hazard ratio [HR] 0.89; 95% CI, 0.85-0.95), and in both acute coronary syndrome (ACS) (HR 0.90; 95% CI, 0.84-0.96) and non-ACS (HR 0.84; 95% CI, 0.77-0.92) patients. Collaterals were associated with improved survival in those receiving angioplasty (HR 0.78; 95% CI, 0.71-0.85) and those with low risk anatomy treated medically (HR 0.84; 95% CI, 0.72-0.98), but not for those treated with coronary bypass graft surgery or those with high-risk anatomy treated without revascularization., Conclusions: The major correlate of coronary collaterals is the presence/extent of obstructive coronary artery disease. Collaterals are associated with better survival overall and in both ACS and non-ACS presentations, but not for those treated with coronary artery bypass graft (CABG) or those with high-risk anatomy who are not revascularized., (Copyright © 2011 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

At least implicitly, most clinical decisions represent an integration of disease and treatment-based risk assessments. Often, as is the case with acute coronary syndrome (ACS), these decisions need to be made quickly at a time when data elements are limited, and published risk models are very useful in clarifying time-dependent determinants of risk. The present review emphasizes the value of explicit risk assessment and reinforces the fact that patients at highest risk are often those most likely to benefit from newer and more invasive therapies. Suggested ways to incorporate published ACS risk models into clinical practice are included. In addition, the need to adopt a longer-term view of risk in ACS patients is stressed, with particular regard to the important role of heart failure prediction and treatment.

Objective: In-stent restenosis (ISR) remains an important problem following percutaneous coronary intervention (PCI). Although it is generally believed that patients with ISR present with stable angina, this has not been well characterized. The aim of this study was to define the incidence, predictors, timing and clinical presentation of patients with ISR requiring repeat catheterization., Design: Using a multiregion prospective database which captures all patients undergoing cardiac catheterization and revascularization in the Province of Alberta, Canada, consecutive bare metal stent (BMS) implantations from January 1, 1998 to December 31, 2002 were analyzed. All patients with a repeat angiogram within one year of the index PCI were reviewed for evidence of clinical-ISR (CISR), defined as ISR as the cause for clinical presentation at angiography., Results: Of the 12,492 consecutive PCI patients reviewed, 2521 had repeat angiography and 744 patients (6.0%) had CISR by study definition. The mean time to repeat angiography in CISR patients was 5.4+/-2.7 months and multivariate analysis identified female gender, diabetes mellitus, and prior PCI as predictors. The majority of patients presented with an acute coronary syndrome: 52.2% unstable angina/non-ST elevation myocardial infarction and 18.5% ST elevation myocardial infarction. Only 25.3% presented with stable exertional angina., Conclusion: Although the incidence of CISR within one year after BMS was relatively low, the recurrent clinical event in the majority of cases was a high-risk coronary syndrome. Thus, careful consideration of the risks of ISR to a specific patient against the cost implications of novel and expensive means to decrease its occurrence is required.

Background: Chelation therapy is frequently used by patients for the treatment of coronary artery disease. However, relatively little is known about patient attitudes and beliefs that underlie the use of this treatment. The aim of the present study was to document patients' opinions and beliefs about health care decision making, physician and patient communication and relationships, and reasons for using or not using chelation therapy as treatment for coronary artery disease., Methods: A mail survey was sent to patients who underwent coronary angiography between 1998 and 2000 in Alberta. Information was collected on self-reported reasons for chelation therapy use, sociodemographic characteristics, communication and relationships between patients and physicians, as well as beliefs regarding surgery, medications and chelation therapy., Results: Of the 780 patients who received surveys, 96 users and 264 nonusers of chelation therapy completed questionnaires. Among the users, 20.8% believed that chelation therapy could cure heart disease, 44.2% believed that it could relieve symptoms, 16.7% believed that it could have side effects and 58.4% believed that it could increase quality of life. Users and nonusers were similar in their beliefs about safety and benefits of heart surgery, but users of chelation therapy were less likely than nonusers to believe that using conventional medications could prevent worsening of heart disease (53.1% versus 67.4%), increase quality of life (74.0% versus 85.2%) and give a feeling of control over heart disease (61.5% versus 77.7%)., Conclusions: Many chelation therapy users appeared to have negative views toward the benefits of conventional medications and positive views toward the safety of chelation therapy. Users and nonusers of chelation therapy had the same views toward the benefits and safety of heart surgery.

Background and Objective: Time-to-event curves are routinely presented in the medical literature. The most widely used method is the Kaplan-Meier (K-M) method, but this analysis approach may not be appropriate when an analysis focuses on time-to-first event in scenarios where there are competing events. We compared K-M methods applying various censoring approaches with the lesser-known "cumulative incidence competing risks" (CICR) method in an analysis of competing events., Methods: A registry containing data on 21,624 patients undergoing cardiac catheterization was analyzed. Time to coronary artery bypass grafting (CABG) was assessed in an analysis for which percutaneous coronary intervention and death were competing events. Time-to-CABG curves were calculated using the "K-M censor all method," "K-M censor death only method," "K-M ignore all method," and the CICR method., Results: One-year CABG rates calculated for the K-M "censor all," "censor death only," and "ignore all" methods were 28.8%, 22.8%, and 22.4%, respectively compared to the "actual" rate of 20.8%. For the CICR method, the corresponding 1-year rate was identical to the "actual" rate., Conclusion: In situations with competing risks, and where an analysis focuses on first events, the CICR method is most appropriate, as K-M methods will tend to overestimate event rates.

Objective: Ordinal scales often generate scores with skewed data distributions. The optimal method of analyzing such data is not entirely clear. The objective was to compare four statistical multivariable strategies for analyzing skewed health-related quality of life (HRQOL) outcome data. HRQOL data were collected at 1 year following catheterization using the Seattle Angina Questionnaire (SAQ), a disease-specific quality of life and symptom rating scale., Study Design and Setting: In this methodological study, four regression models were constructed. The first model used linear regression. The second and third models used logistic regression with two different cutpoints and the fourth model used ordinal regression. To compare the results of these four models, odds ratios, 95% confidence intervals, and 95% confidence interval widths (i.e., ratios of upper to lower confidence interval endpoints) were assessed., Results: Relative to the two logistic regression analysis, the linear regression model and the ordinal regression model produced more stable parameter estimates with smaller confidence interval widths., Conclusion: A combination of analysis results from both of these models (adjusted SAQ scores and odds ratios) provides the most comprehensive interpretation of the data.

Background: Given the repeated findings of little or no difference in mortality outcomes between percutaneous coronary intervention (PCI) with or without stent and coronary artery bypass graft surgery (CABG), there is a need to assess the health-related quality of life (HRQOL) outcomes associated with revascularization decisions., Objective: To compare risk-adjusted HRQOL outcomes by treatment strategy one year following cardiac catheterization., Methods: Using an inception cohort study design, the sample included all Alberta residents, 18 years of age or older, referred for cardiac catheterization, from January 1, 1996, to December 31, 1998, with two or more diseased coronary vessels at catheterization. Patients received a follow-up questionnaire including the Seattle Angina Questionnaire (SAQ), one year following their index catheterization. The SAQ comprises five dimensional scales measuring exertional capacity, anginal stability, anginal frequency, treatment satisfaction and quality of life., Results: Three thousand three hundred ninety-two (78.1%) patients responded to the follow-up survey. Responders who were revascularized consistently reported significantly better HRQOL compared with responders treated with medical management. Responders undergoing CABG reported significantly better HRQOL in all but one SAQ dimension compared with responders who had either a PCI with or without stent. Responders who had a PCI with stent reported better HRQOL compared with responders who underwent a PCI without a stent., Conclusion: The treatment decision to revascularize the coronary vessels, whether with PCI with or without a stent or with CABG, was consistently associated with significantly better HRQOL at one-year follow-up compared with patients treated with medical therapy.

Background: The Seattle Angina Questionnaire (SAQ) is being used with increasing frequency in clinical research to address the health-related quality of life (HRQOL) outcomes of patients with coronary artery disease. The reliability and validity of the SAQ as a disease-specific HRQOL questionnaire has been established. The purpose of this paper was to systematically identify all studies analyzing SAQ scores, and to review the suitability of the statistical methods used., Methods: The literature search included all years from the development of the SAQ (1994) to December 2001. Electronic databases were searched using 'Seattle angina questionnaire' as a key word, text word or medical subject heading, as well as combinations of Seattle, angina and questionnaire. The Scientific Citation Index was searched to identify any manuscripts that cited the developmental articles of the SAQ. Relevant manuscripts were identified as studies that used the SAQ as a measurement tool for HRQOL outcome data., Results: Of the 62 studies identified, 14 articles used the SAQ as an outcome measurement tool. The statistical validity of all but one of the 14 studies was doubtful because assumptions required for the use of parametric tests were not addressed and there was no mention of the distributions of the SAQ scores. Based on the designs of the studies, unsuitable analysis methods were used., Conclusions: Our results demonstrate that investigators may need to increase their attention to the distributional characteristics of their HRQOL data and the design of the study before applying statistical tests to appropriately analyze SAQ HRQOL data.

The problem of missing data is frequently encountered in observational studies. We compared approaches to dealing with missing data. Three multiple imputation methods were compared with a method of enhancing a clinical database through merging with administrative data. The clinical database used for comparison contained information collected from 6,065 cardiac care patients in 1995 in the province of Alberta, Canada. The effectiveness of the different strategies was evaluated using measures of discrimination and goodness of fit for the 1995 data. The strategies were further evaluated by examining how well the models predicted outcomes in data collected from patients in 1996. In general, the different methods produced similar results, with one of the multiple imputation methods demonstrating a slight advantage. It is concluded that the choice of missing data strategy should be guided by statistical expertise and data resources.