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Karin H Humphries

Publications and source records attributed to Karin H Humphries.

At least 19 recordsLinked to original sources
PubMed2006

Identifying priorities in methodological research using ICD-9-CM and ICD-10 administrative data: report from an international consortium.

BACKGROUND: Health administrative data are frequently used for health services and population health research. Comparative research using these data has been facilitated by the use of a standard system for coding diagnoses, the International Classification of Diseases (ICD). Research using the data must deal with data quality and validity limitations which arise because the data are not created for research purposes. This paper presents a list of high-priority methodological areas for researchers using health administrative data. METHODS: A group of researchers and users of health administrative data from Canada, the United States, Switzerland, Australia, China and the United Kingdom came together in June 2005 in Banff, Canada to discuss and identify high-priority methodological research areas. The generation of ideas for research focussed not only on matters relating to the use of administrative data in health services and population health research, but also on the challenges created in transitioning from ICD-9 to ICD-10. After the brain-storming session, voting took place to rank-order the suggested projects. Participants were asked to rate the importance of each project from 1 (low priority) to 10 (high priority). Average ranks were computed to prioritise the projects. RESULTS: Thirteen potential areas of research were identified, some of which represented preparatory work rather than research per se. The three most highly ranked priorities were the documentation of data fields in each country's hospital administrative data (average score 8.4), the translation of patient safety indicators from ICD-9 to ICD-10 (average score 8.0), and the development and validation of algorithms to verify the logic and internal consistency of coding in hospital abstract data (average score 7.0). CONCLUSION: The group discussions resulted in a list of expert views on critical international priorities for future methodological research relating to health administrative data. The consortium's members welcome contacts from investigators involved in research using health administrative data, especially in cross-jurisdictional collaborative studies or in studies that illustrate the application of ICD-10.

Algorithms↗
PubMed2006

True versus reported waiting times for valvular aortic stenosis surgery.

OBJECTIVES: To produce a universally accepted waiting time definition for cardiovascular surgery, present the rationale for this definition, and compare data on current waiting times in British Columbia based on this definition versus the current definition in patients waiting for aortic stenosis surgery. STUDY DESIGN: The present study is a retrospective data analysis. SETTING: The fixed-dollar, single-payer health care delivery system in British Columbia. PATIENTS: All residents of British Columbia who were at least 22 years of age and who were placed on a waiting list for aortic valve surgery with the diagnosis of aortic stenosis between January 1, 1991, and December 31, 2000, were eligible for the present study. INTERVENTIONS: Dates of physician visits, procedures and surgery were obtained from the British Columbia Cardiac Registries and Medical Services Plan databases. True waiting times from physician visits to procedures and surgery were calculated. RESULTS: Of the 2516 patients booked for aortic valve surgery with a primary diagnosis of aortic stenosis, 2237 subjects (88.9%) were eligible for analysis after exclusions. The eligible patients ranged in age from 22 to 95 years, and 36.8% were female. The true median waiting time was 243 days (148 days [25th percentile], 397 days [75th percentile]), which was 3.2 times the interval currently reported as the waiting time (75 days [42, 127]). Thirty-nine patients died while waiting for surgery. Patients used more resources while waiting for surgery than after surgery. CONCLUSIONS: True waiting times for surgery for aortic stenosis in British Columbia are significantly longer than reported waiting times. The authors propose that the wait list time for cardiovascular surgery be redefined as "the time interval between the patient's first contact with a medical care provider with symptoms or signs which ultimately lead to cardiovascular surgery and the date of that surgery".

Adult↗
PubMed2006

Refined characterization of the association between kidney function and mortality in patients undergoing cardiac catheterization.

AIMS: Chronic kidney disease is associated with an increased risk of cardiovascular morbidity and mortality. The level of kidney function at which this risk increases remains to be determined. We sought to characterize the relationship between kidney function and survival among patients with cardiovascular disease (CVD) undergoing cardiac catheterization using estimated glomerular filtration rate (eGFR) and graded refinements in the classification of kidney function. METHODS AND RESULTS: We included 8521 of 11 778 (72.3%) consecutive patients undergoing cardiac catheterization between 1 January 1999 and 31 December 2001 from the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease database. eGFR as a categorical and continuous variable was used to define kidney function. The outcome was all-cause mortality. During a median (interquartile range) follow-up of 2.2 (1.5-3.1) years, and after adjustment for clinical risk factors and severity of coronary disease, there was a steady incremental decrease in survival post-catheterization corresponding to a decline in eGFR categories of 10 mL/min/1.73 m(2). When eGFR was modelled as a continuous variable, there was an increased risk of death noted at an eGFR below 79 mL/min/1.73 m(2). Below an eGFR of 70 mL/min/1.73 m,(2), there was an approximate 17.2% relative increase in risk for every 10 unit decrease in eGFR (95% CI 8.4-26.6%). CONCLUSION: The risk of death post-cardiac catheterization is elevated when eGFR is < or =79 mL/min/1.73 m(2). These findings provide considerable refinement in our understanding of eGFR as a powerful prognostic marker in patients with CVD undergoing cardiac catheterization.

Cardiac Catheterization↗
PubMed2006

Study design of the Multicultural Community Health Assessment Trial (M-CHAT): a comparison of body fat distribution in four distinct populations.

OBJECTIVE: To outline the study design of the Multicultural Community Health Assessment Trial (M-CHAT). The purpose of the study is to compare the relationship between visceral adipose tissue (VAT) and total body fat in men and women of Aboriginal, Chinese, and South Asian origin with a similar group of men and women of European origin. DESIGN: A total of 200 apparently healthy men and women between the ages of 30 and 65 will be recruited from each of the local Aboriginal, Chinese, and South Asian and European communities. Within each sex/ethnic group, an equal representation of participants will have a body mass index between 18.5 to 24.9, 25 to 29.9 and >30. Each participant will undergo an assessment for VAT, total body fat, metabolic risk factors, physical activity, diet, quality of life, and sociodemographics. MAIN OUTCOME MEASURES: The primary outcome of this study is the relationship between VAT and total body fat in each of the Aboriginal, Chinese, and South Asian cohorts; this relationship will be compared to the European cohort after adjustment for age, sex, socioeconomic status, smoking status, physical activity, diet, and body mass index. CONCLUSIONS: This study will be the first to identify differences in body fat distribution in these populations. We anticipate that in populations of Aboriginal, Chinese, and South Asian origin, a greater proportion of total body fat will be deposited as VAT compared to those of European origin.

Adult↗
PubMed2005

Lipoprotein(a) is an independent risk factor for cardiovascular disease in heterozygous familial hypercholesterolemia.

BACKGROUND: The role of lipoprotein(a) [Lp(a)] as a predictor of cardiovascular disease (CVD) in patients with heterozygous familial hypercholesterolemia (HFH) is unclear. We sought to examine the utility of this lipoprotein as a predictor of CVD outcomes in the HFH population at our lipid clinic. METHODS: This was a retrospective analysis of clinical and laboratory data from a large multiethnic cohort of HFH patients at a single, large lipid clinic in Vancouver, Canada. Three hundred and eighty-eight patients were diagnosed with possible, probable, or definite HFH by strict clinical diagnostic criteria. Multivariate Cox regression analysis was used to study the relationship between several established CVD risk factors, Lp(a), and the age of first hard CVD event. RESULTS: An Lp(a) concentration of 800 units/L (560 mg/L) or higher was a significant independent risk factor for CVD outcomes [hazard ratio (HR) = 2.59; 95% confidence interval (CI), 1.53-4.39; P < 0.001]. Other significant risk factors were male sex [HR = 3.19 (1.79-5.69); P < 0.001] and ratio of total to HDL-cholesterol [1.18 (1.07-1.30); P = 0.001]. A previous history of smoking or hypertension each produced HRs consistent with increased CVD risk [HR = 1.55 (0.92-2.61) and 1.57 (0.90-2.74), respectively], but neither reached statistical significance (both P = 0.10). LDL-cholesterol was not an independent predictor of CVD risk [HR = 0.85 (0.0.71-1.01); P = 0.07], nor was survival affected by the subcategory of HFH diagnosis (i.e., possible vs probable vs definite HFH). CONCLUSION: Lp(a) is an independent predictor of CVD risk in a multiethnic HFH population.

Adolescent↗
PubMed2005

Progression to chronic atrial fibrillation after the initial diagnosis of paroxysmal atrial fibrillation: results from the Canadian Registry of Atrial Fibrillation.

BACKGROUND: After its initial diagnosis, atrial fibrillation (AF) may progress from paroxysmal to chronic AF (CAF). The rate of progression and risk factors for progression are not clearly defined. METHODS: The Canadian Registry of Atrial Fibrillation (CARAF) enrolled patients from 6 Canadian cities at the time of their first electrocardiographic diagnosis of AF. Comprehensive clinical and echocardiographic data were collected and patients were followed annually, carefully documenting clinical outcomes, recurrence of paroxysmal AF, and progression to CAF. Baseline clinical, electrocardiographic, and echocardiographic variables were evaluated by univariate Cox proportionate hazards analysis. A stepwise approach was used to model the association between echocardiographic and clinical variables with progression to CAF. RESULTS: A total of 757 patients with a baseline diagnosis of paroxysmal AF were evaluated. Median follow-up was 8.0 years (range 2 days to 11.1 years). The probability of progression to CAF by 1 year was 8.6% and thereafter there was a slow but steady progression to 24.7% by 5 years. By 5 years, the probability of documented recurrence of any AF (chronic or paroxysmal) was 63.2%. Increasing age, significant aortic stenosis or mitral regurgitation, left atrial enlargement, and diagnosis of cardiomyopathy were independently associated with progression to CAF. A more rapid heart rate during AF was associated with decreased risk of progression. CONCLUSIONS: After the initial diagnosis of paroxysmal AF, there is a slow but steady progression to CAF. Baseline echocardiographic variables, age, cardiomyopathy, and heart rate were independently associated with progression to CAF.

Adolescent↗
PubMed2005

Outcomes after percutaneous coronary interventions in patients with CKD: improved outcome in the stenting era.

BACKGROUND: Percutaneous coronary intervention (PCI) with stenting reduces adverse events in the general population compared with balloon angioplasty. The benefit of stents in high-risk patients normally excluded from clinical trials has not been well studied. Outcomes after PCIs in patients with chronic kidney disease (CKD) before and after widespread use of stents were compared. METHODS: All patients undergoing PCIs at our center within 2 periods selected for high and low stent use were included. Demographic, kidney and cardiac function, and PCI data were collected. Kaplan-Meier curves were constructed, and Cox proportional hazards analysis was used to assess the effect of high stent use on major adverse cardiac event, a composite of cardiac revascularization, myocardial infarction, or death 3 years after PCI. RESULTS: A total of 1,879 patients (780 patients, low stent use; 1,099 patients, high stent use; 18% and 94.1% stent use, respectively) with a mean age of 63 years, 73% men, and 26% of patients with a glomerular filtration rate less than 60 mL/min were included. At baseline, there was a greater prevalence of severe CKD, cardiac risk factors, and cardiovascular disease in the high-stent-use cohort. Major adverse cardiac events were reduced in the contemporary cohort (hazard ratio, 0.61; 95% confidence interval, 0.52 to 0.72); this benefit extended across all stages of kidney function. CONCLUSION: Patients with CKD undergoing PCI in the stenting era show improved outcomes. Additional studies are needed to determine optimal revascularization strategies in patients with CKD.

Aged↗
PubMed2005

N-acetylcysteine for prevention of radiographic contrast material-induced nephropathy: is the intravenous route best?

Use of oral N-acetylcysteine for preventing radiographic contrast material-induced nephropathy (RCIN) has become widespread, despite conflicting results from clinical trials and meta-analyses. The variability in study results may reflect differences in baseline risks in study patients, hydration regimens, choice of contrast agent, definition of RCIN, and the oral dosage formulation of N-acetylcysteine used. Injectable N-acetylcysteine recently has become available in the United States. Although oral N-acetylcysteine regimens are typically administered during a 48-hour period, more rapid intravenous administration could offer an important advantage for urgent procedures such as coronary angiography. However, the three published studies in which intravenous N-acetylcysteine protocols were used have produced divergent results, likely because of substantially different dosage regimens. With few intravenous studies available, clinicians may look to more broadly studied oral regimens to estimate equivalent intravenous dosages. In the oral studies, however, a wide range of formulations were used, and the bioavailability of each product was uncertain. In addition, the intravenous route circumvents first-pass metabolism, resulting in less glutathione production, perhaps compromising the antioxidant effects of N-acetylcysteine administration. Overall, little evidence exists that any studied N-acetylcysteine protocol improves clinical outcomes in terms of reducing length of hospital stay, need for dialysis, or mortality. Furthermore, N-acetylcysteine may directly affect serum creatinine level, which all clinical trials to date have used as a primary outcome measure. If oral or intravenous N-acetylcysteine is used with the intention of preventing RCIN, more established preventive measures should not be overlooked, including adequate hydration with isotonic saline, avoidance of potentially nephrotoxic drugs, and use of iso-osmolar radiographic contrast media.

Acetylcysteine↗
PubMed2005

Cross-provincial use of cardiac services: the importance of data-sharing for clinical registries and outcomes research.

BACKGROUND: The structure of the Canadian health care system lends itself to health services and health outcomes research. It is possible to track hospital admissions and discharges, physician billings and prescriptions using administrative databases. In addition, several provinces have developed registries that provide detailed clinical and procedural information. Using the unique personal health numbers assigned to all Canadian residents, linkage between administrative databases and population-based clinical registries provides important information regarding the use of health services and health outcomes. OBJECTIVE: To determine the extent of cross-border (British Columbia-Alberta border) use of cardiac services by British Columbia residents. METHODS: Population rates of cardiac procedures were calculated using two prospective clinical registries (British Columbia Cardiac Registries and Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease [APPROACH]), as well as administrative databases (the British Columbia Ministry of Health's hospitalization and Medical Services Plan databases). RESULTS: Analyses using only British Columbia data suggest low cardiac procedure rates for patients living in eastern British Columbia. By accessing APPROACH data, it was determined that more than 80% of British Columbia cardiac patients living along the British Columbia-Alberta border access procedural services in Alberta. CONCLUSIONS: While residents of eastern British Columbia appear to have reduced access to cardiac services when data from British Columbia are analyzed in isolation, they are actually accessing care in Alberta. Analyses based solely on single province data sources will underestimate cardiac procedures rates.

Adult↗
PubMed2004

The association among renal insufficiency, pharmacotherapy, and outcomes in 6,427 patients with heart failure and coronary artery disease.

OBJECTIVES: This study was designed to examine the use of cardiovascular medications and outcomes in patients with heart failure (HF) and renal dysfunction. BACKGROUND: Renal insufficiency is associated with poorer outcomes in patients with HF, but the mechanisms are uncertain. In particular, the degree of therapeutic nihilism in these patients, and whether it is appropriate, is unclear. METHODS: This was a prospective cohort study with a one-year follow-up. RESULTS: In 6,427 patients with cardiologist-diagnosed HF and angiographically proven coronary artery disease (mean age 69 years; 65% men; one-year mortality, 10%), 39% had creatinine clearances <60 ml/min. Patients with renal insufficiency were less likely to be prescribed angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, statins, or aspirin (all p < 0.001). However, users of aspirin (odds ratio [OR] 0.69, 95% confidence interval [CI] 0.57 to 0.85), statins (OR 0.79, 95% CI 0.64 to 0.97), and beta-blockers (OR 0.75, 95% CI 0.62 to 0.90) were less likely to die in the subsequent 12 months than nonusers, irrespective of renal function (all OR adjusted for covariates including atherosclerotic burden and ejection fraction). Although ACE inhibitor users with creatinine clearances > or =60 ml/min had lower 12-month mortality (OR 0.72, 95% CI 0.48 to 0.99), ACE inhibitor users with clearances <60 ml/min did not (OR 1.21, 95% CI 0.97 to 1.51). CONCLUSIONS: Renal insufficiency is common in patients with HF and coronary artery disease, and these patients have more advanced coronary atherosclerosis. Patients with renal insufficiency are less likely to be prescribed efficacious therapies, but have better outcomes if they receive these medications.

Adrenergic beta-Antagonists↗
PubMed2004

Limitations to antiarrhythmic drug use in patients with atrial fibrillation.

BACKGROUND: Of the antiarrhythmic agents currently marketed in Canada, 5 are commonly used to treat atrial fibrillation (AF). The impact of contraindications, warnings and precautions for the use of these drugs in patients with AF is not known. We evaluated the proportion of patients with AF for whom contraindications, warnings and/or precautions might limit the use of these commonly prescribed drugs and the proportion of patients actually receiving antiarrhythmic drugs despite the presence of contraindications and/or warnings. METHODS: A total of 723 patients with electrocardiographically confirmed, new-onset paroxysmal AF who were enrolled in the Canadian Registry of Atrial Fibrillation were used in this analysis. The 1996 Compendium of Pharmaceuticals and Specialties was used to obtain contraindications, warnings and precautions for use of 5 antiarrhythmic drugs: flecainide, quinidine, sotalol, amiodarone and propafenone. Proportions of patients with contraindications, warnings and/or precautions for use of any of these drugs owing to comorbid conditions or concomitant drug therapy were calculated, regardless of whether the drugs had been prescribed. We then calculated the proportion of patients taking each antiarrhythmic drug at 3 months despite contraindications and/or warnings. RESULTS: At baseline, when conditions for contraindications and warnings were combined, 414 (57%), 235 (33%), 327 (45%), 285 (39%) and 272 (38%) patients had restrictions for the use of flecainide, quinidine, sotalol, amiodarone and propafenone respectively. Among 465 patients actually taking these medications at 3-month follow-up, 33.3% (2/6), 83.3% (40/48), 36.4% (92/253), 64.1% (25/39) and 34.5% (41/119) respectively had contraindications and/or warnings against their use. The burden of comorbid disease among patients with AF was noteworthy: 404 (56%) had structural heart disease, which included 227 (31%) with ischemic heart disease, 158 (22%) with left ventricular systolic dysfunction and 106 (15%) with heart failure. INTERPRETATION: The high burden of comorbid disease and concomitant drug use in a large proportion of patients with AF limits the suitability of existing antiarrhythmic drugs. Over one-third of patients with new-onset AF received antiarrhythmic drugs despite the presence of contraindications or warnings. Although such restrictions may not preclude the use of these drugs, the results demonstrate the need for new antiarrhythmic drugs with fewer limitations.

Aged↗
PubMed2004

Population rates of invasive cardiac procedures in British Columbia, 1995 to 2001.

BACKGROUND: This study examined the rates of coronary angiography (CA), percutaneous coronary intervention (PCI) and coronary artery bypass graft surgery (CABG) in British Columbia (BC) between 1995 and 2001. METHODS: Data sources were as follows: CABG--BC Cardiac Registries; CA and PCI--BC Medical Services Plan; acute coronary syndromes (ACS)--Hospital Separation database; population data--BC Statistics. All rates were age and sex standardized per 100,000 BC resident adults over 20 years of age. RESULTS: The rate of diagnostic CA increased from 352 per 100,000 in 1995 to 400 per 100,000 in 2001 (P<0.01). The rate of PCI increased from 101 per 100,000 in 1995 to 154 per 100,000 in 2001 (P<0.01). Single stage 'ad hoc' PCI increased from 38% in 1995 to 68% in 2001. The rate of CABG remained stable at between 70 and 79 per 100,000. There was a downward trend in the annual hospitalized incidence of ACS (477 to 430 per 100,000, P=0.04). The incidence of ACS and the rates of CA, PCI and CABG were higher for men in all age groups. PCI was more common than CABG in all groups. CONCLUSIONS: The incidence of ACS in BC is falling. The rates of diagnostic CA and PCI are increasing. The latter finding may reflect an appropriate evidence-based response to data supporting greater application of CA following ACS after publication of several studies supporting a routine invasive approach. The PCI rate is rising compared with the CABG rate, likely reflecting changes in patient selection and improved PCI technology, as well as a limited ability of the system to provide surgical procedures.

Adult↗
PubMed2004

Prognostic differences between atrial fibrillation and atrial flutter.

This report presents the outcome of a cohort of 94 patients with atrial fibrillation from the Canadian Registry of Atrial Fibrillation, in which we paid particular attention to the probability of stroke and death. We also evaluated warfarin use over time and compared left atrial dimensions in patients with atrial flutter with those with atrial fibrillation.

Aged↗
PubMed2004

A randomized controlled trial of intravenous N-acetylcysteine for the prevention of contrast-induced nephropathy after cardiac catheterization: lack of effect.

BACKGROUND: Contrast-induced nephropathy (CIN) after cardiac catheterization is common in patients with preexisting renal dysfunction. Studies of oral acetylcysteine to prevent CIN have produced conflicting results. Intravenous N-acetylcysteine (NAC) has logistic advantages in this setting. The objective of this study was to evaluate, in a blinded, randomized, placebo-controlled fashion, whether intravenous NAC reduced CIN in the setting of cardiac catheterization in patients with preexisting renal insufficiency. METHODS: Patients with renal dysfunction undergoing cardiac catheterization were randomly assigned to intravenous NAC 500 mg immediately before the procedure or placebo. All patients received isotonic saline (200 mL) beforehand, followed by 1.5 mL/kg per hour for 6 hours, unless contraindicated. Exclusion criteria included acute renal failure, creatinine >400 micromol/L, concurrent dialysis, unstable clinical status, and prior NAC use. Baseline creatinine was obtained immediately before the procedure and repeated 2 to 8 days later. The primary end point was the occurrence of CIN defined as a reduction in creatinine clearance from baseline of >5 mL/min (Cockcroft-Gault formula). RESULTS: The study was terminated early because of a determination of futility by the Data Safety Monitoring Committee after enrollment of 487 patients. The median baseline creatinine clearance was 44 mL/min (interquartile range, 33, 55). Median contrast received was 120 mL (interquartile range, 80, 175). Baseline characteristics were similar in the two groups. Altogether, 98 (22.0%) subjects had the primary end point: 23.3% in the NAC group and 20.7% in the placebo arm (P =.57). CONCLUSIONS: In this large, randomized trial, enrolling a high-risk group of patients with impaired renal function, intravenous NAC was ineffective in preventing CIN.

Acetylcysteine↗
PubMed2004

The association of left atrial size and occurrence of atrial fibrillation: a prospective cohort study from the Canadian Registry of Atrial Fibrillation.

BACKGROUND: The effect of left atrial (LA) dimension on the recurrence of atrial fibrillation (AF) has been examined in small studies. We evaluated the effect of LA dimension on the occurrence of AF using 2- and 4-year echocardiographic data in a large cohort of patients with new onset AF. METHODS: The Canadian Registry of AF (CARAF) enrolled subjects with AF at the first electrocardiographically confirmed diagnosis. Patients were classified at 2 and 4 years as no recurrent AF (No RAF), paroxysmal AF (PAF), or chronic AF (CAF) based on clinical symptoms and electrocardiographic documentation. The association between baseline, 2-, and 4-year LA dimensions with occurrence of AF as determined by echocardiography was evaluated using a multivariate analysis. RESULTS: The No RAF group (n = 176) had a significantly smaller LA dimension (36.9 +/- 6.8 mm) at baseline compared to the CAF group (n = 227) (42.8 +/- 7.5 mm, P <.0001). The No RAF and PAF (n = 153) groups did not have a significant change in LA dimension at 2 or 4 years. Only those with CAF had a significant increase in LA dimension at 2 and 4 years, +1.39 mm (95% CI 0.01-2.8) and +3.48 mm (95% CI 1.8-5.2), respectively. CONCLUSIONS: A larger baseline LA dimension is associated with progression to CAF. Patients with no or paroxysmal recurrence had no change in LA dimension over a 4-year period. These findings have implications in tailoring modes of therapy in patients with AF.

Aged↗
PubMed2004

New-onset sustained ventricular tachycardia and fibrillation early after cardiac operations.

BACKGROUND: Malignant ventricular tachyarrhythmia early after cardiac surgery is an uncommon arrhythmic complication but has a negative impact on mortality. The purpose of this study was to evaluate the incidence of new-onset sustained postoperative ventricular tachycardia-ventricular fibrillation and to identify risk factors for the dysrhythmia. METHODS: Demographic, clinical, operative, and postoperative data, including a variable of postoperative ventricular tachycardia, were prospectively obtained from 4748 patients undergoing nonemergency coronary artery bypass graft and(or) valve replacement with no history of sustained ventricular tachycardia or sudden death. A detailed analysis was performed to define the risk factors for the ventricular tachycardia and the prognostic impact of the arrhythmia on 30-day mortality was evaluated. RESULTS: Forty-five patients (0.95%) had sustained ventricular tachycardia or ventricular fibrillation and the initial episode occurred 3.9 +/- 5.2 days (mean +/- standard deviation) after surgery. By multivariate analysis, female sex (odds ratio, 1.982), left ventricular ejection fraction (< 35%: > 50%, 4.771), the presence of pulmonary hypertension (3.066), the presence of systemic hypertension (2.391), and pump time (per 10 minutes, 1.085) were independently associated with the dysrhythmias. Early mortality of patients with the arrhythmia was 28.9%, strikingly higher than that of patients without ventricular tachycardia/ventricular fibrillation (1.9%). CONCLUSIONS: Left ventricular ejection fraction is the strongest risk factor for new-onset postoperative sustained ventricular tachycardia-ventricular fibrillation; female sex, pump time, pulmonary and systemic hypertension are independent predictors of the dysrhythmias; the arrhythmia is associated with increased 30-day mortality after cardiac surgery.

Aged↗
PubMed2004

Use of valve surgery in Canada.

BACKGROUND: To date, although clinical databases have been used to report on single centre or regional valve surgery outcomes, neither clinical nor administrative data have been used to examine rates of valve surgery use across large geographical regions. The objective of the present study was to use administrative data to evaluate use of valve surgery over time and across Canada. METHODS: All cases of aortic valve replacement (AVR), mitral valve replacement (MVR), mitral valve repair (MV repair), combined AVR and coronary artery bypass grafting (CABG), and combined MVR/MV repair and CABG between fiscal years 1994/95 and 1999/2000 were identified using hospital discharge abstract data obtained from the Canadian Institute of Health Information. Age- and sex-adjusted rates of valve surgery were then calculated by province and by procedure type. RESULTS: Rates of valve surgery for all procedure types increased between fiscal years 1994/95 and 1999/2000 with the exception of MVR, which remained relatively constant. Significant variation in rates of valve surgery was found between male and female residents. Similar variation was also demonstrated across provinces by year and by procedure type. CONCLUSION: There was a trend toward increased use of valve surgery over time for most procedures. Variation in rates of valve surgery exists across provinces. These results provide a starting point from which to track future trends in use and outcomes for these major procedures.

Adult↗