Regional differences in aortic valve replacements: Atlantic Canadian experience.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) is evolving rapidly and is increasingly being adopted in the treatment of aortic valve disease. The goal of this study was to examine regional differences in surgical aortic valve replacement (SAVR) and TAVI across Atlantic Canada. METHODS: We identified all patients who underwent SAVR or TAVI between Jan. 1, 2010, and Dec. 31, 2014, in New Brunswick, Nova Scotia and Newfoundland and Labrador. Data obtained included patient demographic characteristics and surgical procedure details. We performed univariate descriptive analyses and calculated crude and age- and sex-adjusted incidence rates. RESULTS: A total of 3042 patients underwent SAVR or TAVI during the study period, 1491 in Nova Scotia, 1042 in New Brunswick and 509 in Newfoundland and Labrador. Patient demographic characteristics were similar across regions. A much higher proportion of patients in Newfoundland and Labrador (43.6%) than in Nova Scotia (4.2%) or New Brunswick (13.6%) received a mechanical versus a bioprosthetic valve. Rates of TAVI increased over the study period, with New Brunswick adopting their program before Nova Scotia (144 v. 74 procedures). Adjusted rates of all AVR procedures remained stable in Nova Scotia (40-50 per 100 000 people). Adjusted rates were lower in New Brunswick and Newfoundland and Labrador than in Nova Scotia; they increased slowly in New Brunswick over the study period. CONCLUSION: Despite geographical proximity and similar patient demographic characteristics, there existed regional differences in the management of aortic valve disease within Atlantic Canada. Further study is required to determine whether the observed differences in age- and sex-adjusted rates of AVR may be explained by geographical disease-related differences, varying practice patterns or barriers in access to care.

CONTEXTE: Le remplacement valvulaire aortique par cathéter, une méthode en pleine évolution, est de plus en plus utilisé pour le traitement des valvulopathies aortiques. Cette étude visait à examiner les différences régionales quant au remplacement valvulaire aortique par cathéter ou par chirurgie dans les provinces de l'Atlantique. MÉTHODES: Nous avons recensé tous les patients ayant subi un remplacement valvulaire aortique entre le 1er janvier 2010 et le 31 décembre 2014 au Nouveau-Brunswick, en Nouvelle-Écosse et à Terre-Neuve-et-Labrador. Nous avons recueilli des données sur les caractéristiques démographiques des patients et les interventions chirurgicales, puis nous avons réalisé une analyse descriptive univariée et avons calculé les taux d'incidence bruts et corrigés selon l'âge et le sexe. RÉSULTATS: En tout, 3042 patients ont subi un remplacement valvulaire aortique par cathéter ou par chirurgie pendant la période à l'étude : 1491 en Nouvelle-Écosse, 1042 au Nouveau-Brunswick et 509 à Terre-Neuve-et-Labrador. Les caractéristiques démographiques des patients étaient semblables d'une région à l'autre. La proportion des patients recevant une prothèse mécanique plutôt qu'une bioprothèse était beaucoup plus élevée à Terre-Neuve-et-Labrador (43,6 %) qu'en Nouvelle-Écosse (4,2 %) ou au Nouveau-Brunswick (13,6 %). Les taux de remplacement par cathéter ont augmenté au cours de la période à l'étude; le Nouveau-Brunswick a adopté un programme à ce sujet avant la Nouvelle-Écosse (144 c. 74 interventions). Les taux corrigés pour tous les remplacements étaient stables en Nouvelle-Écosse (40-50 par 100 000 habitants); ils étaient plus faibles au Nouveau-Brunswick et à Terre-Neuve-et-Labrador, mais ont augmenté lentement au Nouveau-Brunswick pendant la période à l'étude. CONCLUSION: Malgré la proximité géographique des provinces de l'Atlantique et les caractéristiques démographiques semblables des patients, il existait des différences dans la prise en charge des valvulopathies aortiques. D'autres études seront nécessaires pour déterminer si les variations dans les taux de remplacement corrigés selon l'âge et le sexe pourraient s'expliquer par des différences géographiques dans le nombre de cas, des différences dans les pratiques ou des obstacles à l'accès aux soins.

Efficacy of intraoperative cell salvage in decreasing perioperative blood transfusion rates in first-time cardiac surgery patients: a retrospective study.

BACKGROUND: Evidence regarding the safety and efficacy of intraoperative cell salvage (ICS) in transfusion reduction during cardiac surgery remains conflicting. We sought to evaluate the impact of routine ICS on outcomes following cardiac surgery. METHODS: We conducted a retrospective analysis of patients who underwent nonemergent, first-time cardiac surgery 18 months before and 18 months after the implementation of routine ICS. Perioperative transfusion rates, postoperative bleeding, clinical and hematological outcomes, and overall cost were examined. We used multivariable logistic regression modelling to determine the risk-adjusted effect of ICS on likelihood of perioperative transfusion. RESULTS: A total of 389 patients formed the final study population (186 undergoing ICS and 203 controls). Patients undergoing ICS had significantly lower perioperative transfusion rates of packed red blood cells (pRBCs; 33.9% v. 45.3% p = 0.021), coagulation products (16.7% v. 32.5% p < 0.001) and any blood product (38.2% v. 52.7%, p = 0.004). Patients receiving ICS had decreased mediastinal drainage at 12 h (mean 320 [range 230-550] mL v. mean 400 [range 260-690] mL, p = 0.011) and increased postoperative hemoglobin (mean 104.7 ± 13.2 g/L v. 95.0 ± 11.9 g/L, p < 0.001). Following adjustment for other baseline and intraoperative covariates, ICS emerged as an independent predictor of lower perioperative transfusion rates of pRBCs (odds ratio [OR] 0.52, 95% confidence interval [CI] 0.31-0.87), coagulation products (OR 0.41, 95% CI 0.24-0.71) and any blood product (OR 0.47, 95% CI 0.29-0.77). Additionally, ICS was associated with a cost benefit of $116 per patient. CONCLUSION: Intraoperative cell salvage could represent a clinically cost-effective way of reducing transfusion rates in patients undergoing cardiac surgery. Further research on systematic ICS is required before recommending it for routine use.

CONTEXTE: Les résultats d'études portant sur l'innocuité et l'efficacité de l'autotransfusion peropératoire (ATPO) comme mesure de réduction du besoin de transfusion durant une chirurgie cardiaque sont contradictoires. Nous avons cherché à évaluer l'incidence du recours systématique à l'ATPO sur les issues de chirurgies cardiaques. MÉTHODES: Nous avons mené une analyse rétrospective portant sur des patients ayant subi une première chirurgie cardiaque non urgente 18 mois avant et 18 mois après l'introduction de l'ATPO systématique. Les taux de transfusion périopératoire et d'hémorragie postopératoire, les résultats cliniques et hématologiques et le coût total ont été analysés. Nous avons utilisé un modèle de régression logistique multivariée pour déterminer l'incidence ajustée en fonction du risque du recours à l'ATPO sur la probabilité qu'une transfusion périopératoire soit nécessaire. RÉSULTATS: L'échantillon à l'étude était composé de 389 patients (186 dans le groupe ATPO et 203 dans le groupe témoin). Par rapport au groupe témoin, les patients ayant reçu une ATPO ont eu besoin significativement moins souvent d'une transfusion de concentrés de globules rouges (33,9 % c. 45,3 %; p = 0,021), de produits coagulants (16,7 % c. 32,5 %; p < 0,001) et de produits sanguins, tous types confondus (38,2 % c. 52,7 %; p = 0,004). Chez les patients ayant reçu une ATPO, on a constaté un volume de drainage médiastinal après 12 h plus faible (moyenne : 320 mL [étendue de 230-550] c. 400 mL [étendue de 260-690]; p = 0,011) et une hémoglobine postopératoire plus élevée (moyenne : 104,7 ± 13,2 g/L c. 95,0 ± 11,9 g/L; p < 0,001). Après des ajustements pour tenir compte d'autres covariables des mesures de base et peropératoires, nous avons conclu que le recours à l'ATPO était un facteur prédicteur indépendant de taux de transfusion périopératoire plus faibles de concentré de globules rouges (rapport de cotes [RC] : 0,52; intervalle de confiance [IC] à 95 % : 0,31-0,87), de produits coagulants (RC : 0,41; IC à 95 % : 0,24-0,71) et de produits sanguins, tous types confondus (RC : 0,47; IC à 95 % : 0,29-0,77). De plus, l'ATPO a été associée à des économies de 116 $ par patient. CONCLUSION: L'autotransfusion peropératoire pourrait constituer un moyen cliniquement efficace en fonction des coûts de réduire les taux de transfusion des patients subissant une chirurgie cardiaque. D'autres recherches sur le recours systématique à l'ATPO devront être menées avant qu'on puisse recommander son utilisation de routine.

Frail patients are at increased risk for mortality and prolonged institutional care after cardiac surgery.

BACKGROUND: Frailty is an emerging concept in medicine yet to be explored as a risk factor in cardiac surgery. Where elderly patients are increasingly referred for cardiac surgery, the prevalence of a frail group among these is also on the rise. We assessed frailty as a risk factor for adverse outcomes after cardiac surgery. METHODS AND RESULTS: Functional measures of frailty and clinical data were collected prospectively for all cardiac surgery patients at a single center. Frailty was defined as any impairment in activities of daily living (Katz index), ambulation, or a documented history of dementia. Of 3826 patients, 157 (4.1%) were frail. Frail patients were older, were more likely to be female, and had risk factors for adverse surgical outcomes. By logistic regression, frailty was an independent predictor of in-hospital mortality (odds ratio 1.8, 95% CI 1.1 to 3.0), as well as institutional discharge (odds ratio 6.3, 95% CI 4.2 to 9.4). Frailty was an independent predictor of reduced midterm survival (hazard ratio 1.5, 95% CI 1.1 to 2.2). CONCLUSIONS: Frailty is a risk for postoperative complications and an independent predictor of in-hospital mortality, institutional discharge, and reduced midterm survival. Frailty screening improves risk assessment in cardiac surgery patients and may identify a subgroup of patients who may benefit from innovative processes of care.

Adverse Outcomes in Obese Cardiac Surgery Patients Correlates With Altered Branched-Chain Amino Acid Catabolism in Adipose Tissue and Heart.

Background: Predicting relapses of post-operative complications in obese patients who undergo cardiac surgery is significantly complicated by persistent metabolic maladaptation associated with obesity. Despite studies supporting the linkages of increased systemic branched-chain amino acids (BCAAs) driving the pathogenesis of obesity, metabolome wide studies have either supported or challenged association of circulating BCAAs with cardiovascular diseases (CVDs). Objective: We interrogated whether BCAA catabolic changes precipitated by obesity in the heart and adipose tissue can be reliable prognosticators of adverse outcomes following cardiac surgery. Our study specifically clarified the correlation between BCAA catabolizing enzymes, cellular BCAAs and branched-chain keto acids (BCKAs) with the severity of cardiometabolic outcomes in obese patients pre and post cardiac surgery. Methods: Male and female patients of ages between 44 and 75 were stratified across different body mass index (BMI) (non-obese = 17, pre-obese = 19, obese class I = 14, class II = 17, class III = 12) and blood, atrial appendage (AA), and subcutaneous adipose tissue (SAT) collected during cardiac surgery. Plasma and intracellular BCAAs and BC ketoacids (BCKAs), tissue mRNA and protein expression and activity of BCAA catabolizing enzymes were assessed and correlated with clinical parameters. Results: Intramyocellular, but not systemic, BCAAs increased with BMI in cardiac surgery patients. In SAT, from class III obese patients, mRNA and protein expression of BCAA catabolic enzymes and BCKA dehydrogenase (BCKDH) enzyme activity was decreased. Within AA, a concomitant increase in mRNA levels of BCAA metabolizing enzymes was observed, independent of changes in BCKDH protein expression or activity. BMI, indices of tissue dysfunction and duration of hospital stay following surgery correlated with BCAA metabolizing enzyme expression and metabolite levels in AA and SAT. Conclusion: This study proposes that in a setting of obesity, dysregulated BCAA catabolism could be an effective surrogate to determine cardiac surgery outcomes and plausibly predict premature re-hospitalization.

Versatility of hemisternotomy for cardiac surgery.

BACKGROUND: Hemisternotomy has been suggested as a way to reduce morbidity by limiting the invasiveness of surgical interventions but it is often limited to aortic valve disease. This study reviews the experience of one center employing hemisternotomy and compares patient outcomes, both in-hospital and post-discharge, with a matched group of full sternotomy patients. METHODS: Propensity scores were used to match all hemisternotomy valve cases (Hemi) to full sternotomy valve cases (Full) (1:2). An in-hospital composite outcome (COMP) was defined as mortality, stroke, deep sternal wound infection, sepsis, or return to operating room (OR) for bleeding or valve dysfunction. Provincial administrative health databases were used to determine freedom from mortality and hospital readmission for cardiac cause. RESULTS: During the study period, 70 patients received hemisternotomy for various cardiac surgical interventions with only 38 patients undergoing isolated aortic valve replacement. Examining valve surgery exclusively, 65 Hemi were matched to 130 Full. In-hospital complications were low in both groups, with 1.0% mortality and a non-significant trend toward COMP in the Full group (Hemi=4.6%; Full=8.5%; p=0.39). Ventilation time was significantly decreased in Hemi (median four vs. six hours; p=0.002). At two years follow-up, survival was excellent for both (Hemi=95.0%; Full=93.6%) and freedom from cardiac morbidity (Hemi=76.8%, Full=73.2%) was comparable. CONCLUSION: Hemisternotomy appears to be a safe, effective, and versatile alternative for many cardiac surgical interventions. With a median follow-up of four years, this study represents the longest cardiac morbidity follow-up for hemisternotomy patients. However, we were unable to conclusively show a morbidity benefit with this incision.

Where you Live in Nova Scotia Can Significantly Impact Your Access to Lifesaving Cardiac Care: Access to Invasive Care Influences Survival.

BACKGROUND: Invasive cardiac care is the preferred method of treatment for patients with acute coronary syndromes (ACS) complicated by cardiogenic shock (CS). In Nova Scotia, invasive cardiac care is only available in Halifax at the Queen Elizabeth II Health Sciences Centre (QEII-HSC). METHODS: All consecutive patients diagnosed with ACS and CS in 2009-2013 in Nova Scotia were included. Data were obtained from the clinical database of Cardiovascular Health Nova Scotia. The primary outcome was in-hospital mortality. RESULTS: A total of 418 patients with ACS and CS were admitted to the hospital. Access to invasive care was limited to 309 (73.9%) of these patients. For those who presented elsewhere in the province, 64.2% were transferred to the QEII-HSC. The mortality rate among the 309 patients with access to invasive care was significantly lower than that among the 109 patients who did not have access (41.7% vs 83.5%; P < 0.0001). Unadjusted mortality was lowest among patients undergoing primary percutaneous coronary intervention (33.1%). After adjustment for clinical differences, access to cardiac catheterization remained an independent predictor of survival (odds ratio, 0.2; 95% confidence interval, 0.11-0.36). Heat map analysis revealed that access was lowest in regions furthest from Halifax. CONCLUSIONS: ACS complicated by CS has a high mortality rate. We demonstrate that access to health care centres offering cardiac catheterization is independently associated with survival, and public health initiatives that improve access should be considered. Patients presenting furthest from Halifax were the least likely to be transferred, suggesting that geography remains an important barrier to livesaving care.

Family practice patients' adherence to statin medications.

OBJECTIVE: To measure family practice patients' adherence to statin medications and to identify factors associated with adherence to these medications. DESIGN: Cross-sectional study using a mailed self-report survey sent to 400 patients. SETTING: Two academic family practice clinics in Halifax, NS. PARTICIPANTS: A total of 284 patients aged 40 or older who were prescribed statin medications by their family physicians, either for the first time or as a renewal during a 20-month period. MAIN OUTCOME MEASURES: Level of adherence to statin medications as measured by patients' self-report on the Morisky scale; association between high adherence on the Morisky scale and 38 patient-reported factors. RESULTS: Response rate was 82.5%. Average age of patients was 65 years, 57% were men, 62% had been on statin medications for more than 2 years, and 97% reported that their family physicians managed their cholesterol levels. More than 63% of patients reported high adherence as measured by the Morisky scale. On multiple logistic regression, being older than 65, taking 4 to 6 other prescribed medications, and having a lifestyle that included regular exercise or a healthy diet were significant independent predictors of high adherence scores on the Morisky scale. CONCLUSION: Almost two-thirds (63%) of patients who were prescribed statins by their family physicians reported high adherence to the medications. Strategies to improve adherence would best be directed at patients who are younger or taking fewer than 4 or more than 6 other prescribed medications. Patients should be encouraged to maintain a lifestyle of regular exercise and a healthy diet, as this was associated with better adherence to statin medications.

Impact of Obesity on Intensive Care Unit Resource Utilization After Cardiac Operations.

BACKGROUND: Much has been published about the effect of obesity on adverse outcomes after cardiac operations, yet little is known regarding the effect of obesity on intensive care unit (ICU) resource utilization. This study examined the effect of obesity on ICU resource utilization after cardiac operations. METHODS: All patients with a body mass index (BMI) of 18.5 kg/m2 or higher who underwent a cardiac surgical procedure between 2006 and 2013 were stratified into the following weight categories: normal (BMI 18.5 to 24.99 kg/m2), preobese (BMI 25 to 29.99 kg/m2), obese class I (BMI 30 to 34.99 kg/m2), obese class II (BMI 35 to 39.99 kg/m2), and obese class III (BMI ≥40 kg/m2). Comparisons between weight categories were done, and the risk-adjusted effect of weight category on prolonged ICU stay, prolonged ventilation, and ICU readmission was determined. RESULTS: Of the 5,365 included patients, 1,948 were obese. Patients with greater obesity experienced longer ICU time, longer ventilation time, and increased ICU readmission. After adjustment, increasing obesity remained independently associated with greater likelihood of prolonged ICU stay (obese class II: odds ratio [OR], 2.4; 95% confidence interval [CI], 1.55 to 3.61; obese class III: OR, 4.1; 95% CI, 2.38 to 7.05), prolonged ventilation (obese class III: OR, 3.4; 95% CI, 1.57 to 7.22), and ICU readmission (obese class II: OR, 3.0; 95% CI, 1.70 to 5.31; obese class III: OR, 2.9; 95% CI, 1.32 to 6.36). CONCLUSIONS: Increasing obesity was associated with a significant increase in ICU resource utilization after cardiac operations. Further study is needed to determine the mechanisms underlying this association and how the adverse effects of obesity may be mitigated.

Lysophosphatidic acid receptor mRNA levels in heart and white adipose tissue are associated with obesity in mice and humans.

BACKGROUND: Lysophosphatidic acid (LPA) receptor signaling has been implicated in cardiovascular and obesity-related metabolic disease. However, the distribution and regulation of LPA receptors in the myocardium and adipose tissue remain unclear. OBJECTIVES: This study aimed to characterize the mRNA expression of LPA receptors (LPA1-6) in the murine and human myocardium and adipose tissue, and its regulation in response to obesity. METHODS: LPA receptor mRNA levels were determined by qPCR in i) heart ventricles, isolated cardiomyocytes, and perigonadal adipose tissue from chow or high fat-high sucrose (HFHS)-fed male C57BL/6 mice, ii) 3T3-L1 adipocytes and HL-1 cardiomyocytes under conditions mimicking gluco/lipotoxicity, and iii) human atrial and subcutaneous adipose tissue from non-obese, pre-obese, and obese cardiac surgery patients. RESULTS: LPA1-6 were expressed in myocardium and white adipose tissue from mice and humans, except for LPA3, which was undetectable in murine adipocytes and human adipose tissue. Obesity was associated with increased LPA4, LPA5 and/or LPA6 levels in mice ventricles and cardiomyocytes, HL-1 cells exposed to high palmitate, and human atrial tissue. LPA4 and LPA5 mRNA levels in human atrial tissue correlated with measures of obesity. LPA5 mRNA levels were increased in HFHS-fed mice and insulin resistant adipocytes, yet were reduced in adipose tissue from obese patients. LPA4, LPA5, and LPA6 mRNA levels in human adipose tissue were negatively associated with measures of obesity and cardiac surgery outcomes. This study suggests that obesity leads to marked changes in LPA receptor expression in the murine and human heart and white adipose tissue that may alter LPA receptor signaling during obesity.

Increased Distance From the Tertiary Cardiac Center Is Associated With Worse 30-Day Outcomes After Cardiac Operations.

BACKGROUND: Numerous studies have examined the effect of geographic place of residence on access to cardiovascular care, but few have examined their effect on outcomes after cardiac operations. This study examined the effect of geographic place of residence on in-hospital and 30-day outcomes after cardiac operations. METHODS: We performed a retrospective analysis of all patients undergoing nonemergency cardiac operations at a single institution between April 2004 and March 2011. Geographic place of residence was defined as the driving distance from the patient's home to the tertiary cardiac care center divided into the following categories: 0 to 50 km, 50 to 100 km, 100 to 150 km, 150 to 200 km, 200 to 250 km, and more than 250 km. Multivariable logistic regression was used to determine the independent effect of driving distance on in-hospital and 30-day outcomes. RESULTS: The final study population included 4,493 patients, of whom 3,897 (86.7%) had 30-day follow-up. After adjusting for differences among patient groups, no consistent relationship existed between distance and in-hospital outcomes. However, increased distance beyond 100 km was significantly associated with a greater risk of adverse outcomes at 30 days (0 to 50 km: referent; 50 to 100 km: odds ratio, 1.16 [95% confidence interval, 0.83 to 1.62]; 100 to 150 km: 1.32 [1.05 to 1.65], 150 to 200 km: 1.68 [1.33 to 2.11], 200 to 250 km: 1.41 [1.06 to 1.88], and >250 km: 1.30 [1.04 to 1.63]). CONCLUSIONS: Patients who live at an increased distance from the tertiary cardiac care center are more likely to have worse 30-day outcomes after cardiac operations. Further study is required to determine the mechanisms underlying this relationship and how such inequalities may be minimized.

Variation in transfusion rates within a single institution: exploring the effect of differing practice patterns on the likelihood of blood product transfusion in patients undergoing cardiac surgery.

OBJECTIVES: Rates of perioperative transfusion vary widely among patients undergoing cardiac surgery. Few studies have examined factors beyond the clinical characteristics of the patients that may be responsible for such variation. The purpose of this study was to determine whether differing practice patterns had an impact on variation in perioperative transfusion at a single center. METHODS: Patients who underwent cardiac surgery at a single center between 2004 and 2011 were considered. Comparisons were made between patients who had received a perioperative transfusion and those who had not from the clinical factors at baseline, intraoperative variables, and differing practice patterns, as defined by the surgeon, anesthesiologist, perfusionist, and the year in which the procedure was performed. The risk-adjusted effect of these factors on perioperative transfusion rates was determined using multivariable regression modeling techniques. RESULTS: The study population comprised 4823 patients, of whom 1929 (40.0%) received a perioperative transfusion. Significant variation in perioperative transfusion rates was noted between surgeons (from 32.4% to 51.5%, P < .0001), anesthesiologists (from 34.4% to 51.9%, P < .0001) and across year (from 28.2% in 2004 to 48.8% in 2008, P < .0001). After adjustment for baseline and intraoperative variables, surgeon, anesthesiologist, and year of procedure were each found to be independent predictors of perioperative transfusion. CONCLUSIONS: Differing practice patterns contribute to significant variation in rates of perioperative transfusion within a single center. Strategies aimed at reducing overall transfusion rates must take into account such variability in practice patterns and account for nonclinical factors as well as known clinical predictors of blood transfusions.

Individual and neighbourhood determinants of health care utilization. Implications for health policy and resource allocation.

OBJECTIVES: To investigate the importance of both individual and neighbourhood socioeconomic characteristics for health care utilization. METHODS: Various linkage procedures generated a longitudinal dataset with information on 2,116 Nova Scotians, their residential neighbourhoods, 8 years of health care utilization and vital status. Unilevel and multilevel regression analyses were employed to examine the effects of both individual and neighbourhood characteristics on health care use. RESULTS: Individual income and education determined physician and hospital use. Also, neighbourhood characteristics, specifically average income and percentage of single mother families, were found to determine health care use. When considering individual and neighbourhood characteristics simultaneously, individual income and education determined physician and hospital use independently, while neighbourhood income determined physician use independently. CONCLUSIONS: Both individual and neighbourhood socioeconomic characteristics determine health care use. Acknowledging this allows better targeting of health policy and planning, and enables more accurate needs-based resource allocation.

Dietary iron as a risk factor for myocardial infarction. Public health considerations for Nova Scotia.

BACKGROUND: Epidemiological and experimental studies have suggested that high levels of dietary iron and hemeiron can lead to myocardial injury. Lean meat, a primary source of iron and hemeiron, is promoted because it is lower in fat and cholesterol. Does lean meat put us at risk for myocardial infarction, and should we reconsider its promotion? METHODS: We analyzed the importance of dietary iron and hemeiron as a risk for myocardial infarction among 2,198 Nova Scotians who participated in a nutrition survey and who were followed for eight years, using logistic regression. RESULTS: Acute myocardial infarction incidents occurred in 94 (4.3%) participants. We found no increased risk for myocardial infarction associated with high intake of iron and hemeiron. CONCLUSIONS: Based on Nova Scotian data showing no increased risk for myocardial infarction with high intake of iron and hemeiron, there is no need for immediate reconsideration of promotion of lean meat.

Myocardium at risk is associated with adverse clinical events in women but not in men, after coronary artery bypass grafting.

BACKGROUND: Women undergoing coronary artery bypass grafting (CABG) are at increased risk for morbidity and mortality. Factors responsible for this observation include smaller coronary size and delayed presentation. To date, no studies have examined the effect of the degree of myocardium at risk (MAR) on the relationship between female sex and adverse postoperative events. METHODS: Consecutive patients undergoing first-time isolated CABG at a single institution from 2002-2007 were identified. MAR was calculated using the weighted Duke Index and was categorized as low, moderate, or high. Multivariable logistic regression models were created to compare the impact of MAR on adverse clinical events. RESULTS: We identified 3741 patients, 3325 (89%) of whom had complete angiographic data. Women (n = 755) were older (P = 0.0001) and presented more often with hypertension (P = 0.0001), diabetes (P = 0.0001), heart failure (P = 0.0001), and an urgent/emergent situation (P = 0.002). After surgery, women experienced greater rates of adverse events (15.2% vs 9.3%; P = 0.0001). In a fully adjusted logistic regression model, the nested interaction of sex in MAR showed that women had a significantly greater risk of major adverse cardiovascular events (MACE) when MAR was high (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.3-2.6; P = 0.0004). Greater severity of MAR emerged as an independent predictor of adverse events among women (high: OR, 2.9; 95% CI, 1.2-7.3; moderate: OR, 2.2; 95% CI, 0.8-5.7; low: OR, 1.0), but not among men. CONCLUSIONS: MAR was independently associated with higher rates of adverse events among women but not in men undergoing CABG. This finding may help explain differences in outcomes seen between women and men after revascularization.

Determinants of percutaneous coronary intervention vs coronary artery bypass grafting: an interprovincial comparison.

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.

The impact of sequential grafting on clinical outcomes following coronary artery bypass grafting.

OBJECTIVES: Sequential anastomoses in coronary artery bypass grafting (CABG) offer theoretical advantages including increased graft flow and more complete revascularisation. However, published studies concerning the safety and efficacy of this technique are not definitive. The objective of this study was to assess the effect of sequential anastomoses on outcomes following CABG. METHODS: Perioperative data were prospectively collected on all patients with triple-vessel disease who underwent first-time, isolated, on-pump CABG between 1995 and 2005 at a single centre. Patients with a left internal mammary artery graft to the anterior wall and saphenous vein grafts to the lateral and posterior walls were included. RESULTS: Compared to patients without sequential anastomoses (n=1108), patients with sequential anastomoses (n=1246) were more likely to have an ejection fraction (EF)<40% (14.9% vs 10.8%, p=0.004), a recent myocardial infarction (19.3% vs 14.3%, p=0.001) and an urgent/emergent operative status (19.6% vs 14.4%, p=0.0008). Median follow-up was 78 months. After adjusting for clinical covariates, sequential grafting was not an independent predictor of in-hospital adverse events (odds ratio (OR) 1.15, 95% confidence interval (CI) 0.88-1.50, p=0.31) or long-term mortality and/or readmission to hospital (hazard ratio (HR) 0.98, 95% CI 0.86-1.12, p=0.74). Sequential grafting was an independent predictor of receiving greater than three distal anastomoses (OR 9.26, 95% CI; 6.27-13.67, p<0.0001). CONCLUSIONS: Patients undergoing sequential grafting presented with greater acuity and worse systolic function. After adjusting for baseline differences, sequential grafting was not found to be an independent predictor of adverse events. These results support the safety of sequential anastomoses in patients undergoing CABG.

Predicting prolonged intensive care unit length of stay in patients undergoing coronary artery bypass surgery--development of an entirely preoperative scorecard.

We sought to develop a predictive model based exclusively on preoperative factors to identify patients at risk for PrlICULOS following coronary artery bypass grafting (CABG). Retrospective analysis was performed on patients undergoing isolated CABG at a single center between June 1998 and December 2002. PrlICULOS was defined as initial admission to ICU exceeding 72 h. A parsimonious risk-predictive model was constructed on the basis of preoperative factors, with subsequent internal validation. Of 3483 patients undergoing isolated CABG between June 1998 and December 2002, 411 (11.8%) experienced PrlICULOS. Overall in-hospital mortality was higher among these patients (14.4% vs. 1.2%, P

Inequalities in health and health services delivery: a multilevel study of primary care and hypertension control.

Delivery of health services is an important determinant of health. Restricted availability and access may result in health inequalities. To determine the extent of geographic variation in the delivery of health services and its effect on the health of community residents in terms of under-diagnosis and under-treatment of hypertension, we carried out a multilevel study of participants in the 1995 Nova Scotia Heart Health Survey (n = 3,094). We used individual level survey data and health status measurements linked to geographical level information to examine the importance of adequate delivery of health services to the diagnosis and treatment of hypertension in the universal health care setting of the province of Nova Scotia. The delivery of primary care services across Nova Scotia varied moderately with physician visit rates ranging from 3.3 to 5.5 visits per resident per year. There were neither substantial nor statistically significant differences in the diagnosis and treatment of hypertension among residents of communities varying in the delivery of health services. We concluded that a geographic variation in the delivery of primary care services is a public health concern that is not consistent with the objectives of universal coverage of health services; however, it was not confirmed to result in health inequalities.

Geographic variation in health services use in Nova Scotia.

To further our understanding of factors underlying geographic variation in health and the potential role of availability of and access to health services, we sought to quantify the geographic variation in health services use in the province of Nova Scotia. For the period 1996 to 1999 we examined the variation in the use of health services across 64 geographic areas in conjunction with health and socio-economic factors, using multilevel methods and empirical Bayesian estimates based on provincial physician billings and hospital separation records. We revealed moderate geographic variation in the use of family physician services and large variation in specialist and hospital services. In the two urban centres, Metropolitan Halifax and the Cape Breton Regional Municipality, use of specialist services was respectively 26.24% and 15.59% higher than the provincial average, and use of hospital services was respectively 21.55% and 37.67% higher. Geographic areas in which residents had better health were characterized by more use of family physician services and reduced use of specialist and hospital services. These associations seem to support policy strategies that aim to improve health and to reduce health care costs by investing in prevention and primary health care, and they highlight the potential implications of the shortage of family physicians across Canada.