Trends in coronary artery revascularisation procedures in Western Australia, 1980-2001

One-Year Outcomes of Patients With Established Coronary Artery Disease Presenting With Acute Coronary Syndromes

The risk of major adverse cardiovascular events (MACE) remains high in patients with established coronary artery disease (CAD). The aim of this study was to assess the prognostic significance of established CAD in patients who present with acute coronary syndromes (ACS) using a large established multicenter registry. Consecutive patients from the Melbourne Interventional Group registry who presented with ACS and underwent percutaneous coronary intervention from 2005 to 2015 were included. Patients with a history of myocardial infarction, percutaneous coronary intervention, or coronary artery bypass graft surgery were included in the established CAD cohort. The primary end points were 12-month mortality and 12-month MACE. Of the 12,878 ACS patients included in our study, 3,542 (28%) patients had established CAD. Over the 10-year study period, the proportion of patients presenting with established CAD decreased (30.7% to 25.2%; p-for-overall-trend <0.001). Non-ST elevation myocardial infarction was the most prominent presentation in the established CAD cohort (45.1%) whereas ST-elevation myocardial infarction was the most prominent in the de novo CAD cohort (51%; p< 0.001). The patients in the established CAD cohort were older, had more co-morbidities and were more likely to present with high-risk features such as atrial fibrillation, left main disease, multivessel CAD and left ventricular dysfunction (all p < 0.001). Regarding revascularization in ST-elevation myocardial infarction presentations, symptom-to-door time was shorter, whereas door-to-balloon-time was longer in those with established CAD (p < 0.001). On multivariate analysis, established CAD was an independent risk factor for 12-month MACE (odds ratio 1.40, 95% confidence intervals 1.23 to 1.58, p < 0.001), but not for 12-month mortality (odds ratio 1.08, 95% confidence intervals 0.77 to 1.52, p = 0.66). In conclusion, patients with a history of myocardial infarction or previous revascularization have a higher rate of MACE at 12 months. Despite this they do not appear to suffer from higher mortality.

Outcomes of patients with prior coronary artery bypass graft who present with acute coronary syndrome

Generally, patients with prior coronary artery bypass graft (CABG) are often under-represented in acute coronary syndrome (ACS) clinical trials. Nevertheless, there is growing global attention concerning their short- and long-term prognosis. Some reports suggest prior CABG as an independent risk factor for increased mortality, while others report an equal or a more favorable prognosis despite their adverse baseline clinical characteristics. The reasons for this 'risk-mortality paradox' need to be further evaluated. More recent reports showed a significant reduction in in-hospital morbidity and mortality over a 20-year period of follow up that may be attributed to the improvement in surgical CABG techniques and increased use of evidence-based therapies over the past two decades. In the current review we discuss the available literature regarding outcomes of prior CABG patients who are presenting with ACS.

Impact of the introduction of drug eluting stents on clinical outcomes in patients undergoing percutaneous and surgical coronary artery revascularisation procedures in Western Australia

Background

Increasing rates of percutaneous coronary intervention (PCI) and decreasing rates of coronary artery bypass graft (CABG) surgery followed the introduction of drug eluting stents in Western Australia in 2002. We assessed the impact of these changes on one-year outcomes for the total population of patients undergoing coronary artery revascularisation procedures (CARP) in Western Australia between 2000-2004.

Methods

Clinical and linked administrative data (inpatient admissions and death) were merged for all patients who had their first CARP with stent or CABG in Western Australia between 2000-2004. The clinical data were collected from all hospitals in Western Australia where CARP procedures are performed. We calculated the unadjusted (Kaplan-Meier) and adjusted (Cox) risks for one-year death (all-cause), death (all-cause) or admission for myocardial infarction (MI), target vessel revascularisation (TVR) and the composite outcome of death/MI/TVR (major adverse cardiac events, MACE).

Results

Over the study period, there were 14,118 index CARPs. The use of drug eluting stents increased from 0% to 95.8% of PCI procedures, and PCI procedures increased from 61.1% to 74.4% of all CARPS. There were no temporal changes in adjusted one-year mortality or death/MI. Overall, adjusted one-year MACE fell from 11.3% in 2000 to 8.5% in 2004 (p<0.0001) due to a significant reduction in TVR in the PCI group.

Conclusion

The introduction of drug eluting stents and resulting changes in coronary revascularisation strategies were not associated with changes in the one-year risk of major clinical endpoints (death or death/MI), but were associated with a significant reduction in the risk of MACE, driven entirely by a reduction in TVR after PCI. This real world study supports the effectiveness of drug eluting stents in reducing repeat procedures in the total CARP population without increasing the risk of death or MI.

Trends in long-term cardiovascular mortality and morbidity in men and women with heart failure of ischemic versus non-ischemic aetiology in Western Australia between 1990 and 2005

BACKGROUND

It is uncertain if improvements in long-term cardiovascular (CV) mortality have occurred in both men and women with ischemic and non-ischemic forms of heart failure (HF).

METHODS

The Western Australia Hospital Morbidity Database was used to identify all index (first-ever) hospitalizations for HF between 1990 and 2005. Patients were followed until death attributed to cardiovascular causes or censored on December 31, 2006 to determine 5-year survival. Cox proportional hazards models were used to compare the adjusted mortality hazard ratio (HR) during the study follow-up (4-year periods).

RESULTS

A total of 21,507 patients (mean age 73.9 years, 49.1% women) were identified. Women were significantly older than men, and less likely to have ischemic HF (38.8% versus 46.1%). Over the period, age-standardized incidence of first HF hospitalization declined but with the least decline in women with non-ischemic HF (-13.3%) compared to other subgroups. Risk-adjusted 5-year CV mortality declined over the study period, with HR 0.64 (95% CI 0.60-0.68) for patients admitted in 1998-2001 compared to 1990-1993, with significant improvement in both forms of HF, and in both sexes and across age groups. However, overall total HF hospitalizations increased (+26.7%) over the period, particularly for non-ischemic HF (+43.7%), of which elderly women formed the predominant group.

CONCLUSIONS

Risk-adjusted long-term survival improved similarly in men and women, including the elderly, with ischemic and non-ischemic forms of HF during 1990-2005 in Western Australia. However, there was a growing burden of HF hospitalizations particularly for HF of non-ischemic aetiology.

Platelet gene polymorphisms and risk of bleeding in patients undergoing elective coronary angiography: a genetic substudy of the PRAGUE-8 trial

AIM

Utilization of cardiac catheterization has increased dramatically over time. Bleeding is a major prognostic predictor after percutaneous coronary catheterization procedures. This study aimed to assess the impact of eight polymorphisms of genes encoding platelet receptors and enzymes on the risk of bleeding in patients undergoing elective coronary angiography (CAG).

METHODS

Polymorphisms of platelet receptors, GP Ia (807C>T, rs1126643), GP VI (13254T>C, rs1613662), GP IIIa (HPA-1, rs5918), PAR-1 (IVS-14A>T, rs168753), P2Y(12) (34C>T, rs6785930 and H1/H2 haplotype, rs2046934), and genetic variations of the gene coding for cyclooxygenase-1 (COX-1) (-842A>G, rs10306114 and 50C>T, rs3842787) were studied. The frequencies of gene polymorphisms carriers were investigated in 696 patients undergoing elective CAG because of suspected or proven stable coronary artery disease. Genotyping was done using PCR, followed by melting curve analysis with specific fluorescent hybridization probes.

RESULTS

In patients undergoing elective CAG (without ad hoc percutaneous coronary intervention (PCI) and without clopidogrel pretreatment) a significant association was found between bleeding risk and variations in the gene coding for COX-1 (-842A>G and 50C>T) (both p=0.013). Six other investigated polymorphisms did not show any influence on bleeding complications. After controlling for potential bleeding confounders, the association between COX-1 gene polymorphisms (-842A>G and 50C>T) and bleeding risk remained statistically significant (both odds ratios 12.1, p=0.012).

CONCLUSION

Cyclooxygenase-1 -842G and 50T alleles significantly contribute to the risk of bleeding complications in patients undergoing elective CAG. Genetic testing is able to influence the safety of diagnostic cardiac catheterization in large numbers of low risk patients with borderline indications.

Erectile dysfunction as a predictor for subsequent atherosclerotic cardiovascular events: findings from a linked-data study

INTRODUCTION

In spite of the mounting interest in the nexus between erectile dysfunction (ED) and cardiovascular (CV) diseases, there is little published information on the role of ED as a predictor for subsequent CV events.

AIM

This study aimed to investigate the role of ED as a predictor for atherosclerotic CV events subsequent to the manifestation of ED. Method. The investigation involved the retrospective study of data on a cohort of men with ED linked to hospital morbidity data and death registrations. By using the linked data, the incidence rates of atherosclerotic CV events subsequent to the manifestation of ED were estimated in men with ED and no atherosclerotic CV disease reported prior to the manifestation of ED. The risk of subsequent atherosclerotic CV events in men with ED was assessed by comparing these incidence rates with those in the general male population.

MAIN OUTCOME MEASURE

Standardized incidence rate ratio (SIRR), comparing the incidence of atherosclerotic CV events subsequent to the manifestation of ED in a cohort of 1,660 men with ED to the incidence in the general male population.

RESULTS

On the basis of hospital admissions and death registrations, men with ED had a statistically significantly higher incidence of atherosclerotic CV events (SIRR 2.2; 95% confidence interval 1.9, 2.4). There were significantly increased incidence rate ratios in all age groups younger than 70 years, with a statistically highly significant downward trend with increase of age (P < 0.0001) across these age groups. Younger age at first manifestation of ED, cigarette smoking, presence of comorbidities and socioeconomic disadvantage were all associated with higher hazard ratios for subsequent atherosclerotic CV events.

CONCLUSIONS

The findings show that ED is not only significantly associated with but is also strongly predictive of subsequent atherosclerotic CV events. This is even more striking when ED presents at a younger age.

Nationwide trends in the utilization of multivessel percutaneous coronary intervention (MVPCI) in the United States across different gender and ethnicities

BACKGROUND

To evaluate nationwide trends in the utilization of Multivessel Percutaneous Coronary Intervention (MVPCI) in the past compared to recent years using a large database from 1988 to 2004.

METHOD

The Nationwide Inpatient Sample (NIS) database was utilized to calculate the age-adjusted rate for multivessel percutaneous coronary intervention (MVPCI) from 1988 to 2004. Specific ICD-9-CM codes for MVPCI were used to compile the data. Patient demographic data were also analyzed from the database.

RESULTS

According to the NIS database, MVPCI was performed in 241,319 patients from 1988 to 2004. Males underwent MVPCI twice as many as compared to females (male: 67.87%, female 32.13%). The mean age for these patients was 64.89 +/- 11.84 years old. From 1988, the age-adjusted rate for MVPCI gradually increased to more than three times in 1998 [(6.62 per 100,000 (95%CI = 5.92-7.33) in 1988 to 23.92 per 100,000 (95%CI = 21.62-26.22, P < 0.01) in 1998] and accelerated to more than 6 times that of 1988 at the end of the study in 2004 (41.50 per 100,000 (95%CI = 37.84-45.16). In recent years, this trend was similar for both genders and ethnicities.

CONCLUSION

The utilization of MVPCI has increased six times from 1988 to 2004, with acceleration in recent years. The cause of this acceleration is most likely related to the advancement in the percutaneous coronary interventional techniques.

Long term survival after evidence based treatment of acute myocardial infarction and revascularisation: follow-up of population based Perth MONICA cohort, 1984-2005

OBJECTIVE

To examine trends in long term survival in patients alive 28 days after myocardial infarction and the impact of evidence based medical treatments and coronary revascularisation during or near the event.

DESIGN

Population based cohort with 12 year follow-up.

SETTING

Perth, Australia.

PARTICIPANTS

4451 consecutive patients with a definite acute myocardial infarction according to the World Health Organization MONICA (monitoring trends and determinants in cardiovascular disease) criteria admitted to hospital during 1984-7, 1988-90, and 1991-3.

MAIN OUTCOME MEASURES

All cause mortality identified from official mortality records and the hospital morbidity data, with death from cardiovascular disease as a secondary end point.

RESULTS

In the 1991-3 cohort, 28 day survivors of acute myocardial infarction had a 7.6% absolute event reduction (95% confidence interval 4% to 11%) or a 28% lower relative risk reduction (16% to 38%), unadjusted for risk of death, over 12 years after the incident admission compared with the 1984-7 cohort, similar to the survival of the 1988-90 cohort. The improved survival for the 1991-3 cohort persisted after adjustment for demographic factors, coronary risk factors, severity of disease, and event complications with an adjusted relative risk reduction of 26% (14% to 37%), but this was not apparent after further adjustment for medical treatments in hospital and coronary revascularisation procedures within 12 months of the incident myocardial infarction.

CONCLUSION

The improving trends in 12 year survival after a definite acute myocardial infarction are associated with progressive use of evidence based treatments during the initial admission to hospital and in the 12 months after the event. These changes in the management of acute myocardial infarction are probably contributing to the continuing decline in mortality from coronary heart disease in Australia.

Trends in percutaneous coronary interventions in new South Wales, Australia

This is the first detailed study on percutaneous coronary intervention (PCI) in New South Wales (NSW), Australia. Hospital data for PCIs carried out between 1 July 1990 and 30 June 2002 are analysed. The study explores trends in PCI rates by selected socio-demographic factors, the utilisation of angioplasties vis-a-vis stents, emergency admissions, and selected coexisting conditions which determine the disease status of PCI patients. Logistic regression models are used to study the medical conditions that require both PCI and coronary artery bypass graft (CABG). The PCI rate has grown rapidly at 12.1% per annum, with a particularly rapid increase for persons aged 75+. The rate of multiple stent utilisation increased at 4.6% per annum. Pacific-born and Middle-Eastern-born patients are more than twice as likely as the Australian-born to have diabetes. Factors affecting failure of PCI requiring CABG include perforation and multi-vessel disease. PCI services in public hospitals need to be increased to facilitate the availability of these procedures to all segments of the population, as do targeted community-level programmes to educate high-risk groups in the control of heart diseases.

Adapting a Markov Monte Carlo simulation model for forecasting the number of coronary artery revascularisation procedures in an era of rapidly changing technology and policy

BACKGROUND

Treatments for coronary heart disease (CHD) have evolved rapidly over the last 15 years with considerable change in the number and effectiveness of both medical and surgical treatments. This period has seen the rapid development and uptake of statin drugs and coronary artery revascularization procedures (CARPs) that include Coronary Artery Bypass Graft procedures (CABGs) and Percutaneous Coronary Interventions (PCIs). It is difficult in an era of such rapid change to accurately forecast requirements for treatment services such as CARPs. In a previous paper we have described and outlined the use of a Markov Monte Carlo simulation model for analyzing and predicting the requirements for CARPs for the population of Western Australia (Mannan et al, 2007). In this paper, we expand on the use of this model for forecasting CARPs in Western Australia with a focus on the lack of adequate performance of the (standard) model for forecasting CARPs in a period during the mid 1990s when there were considerable changes to CARP technology and implementation policy and an exploration and demonstration of how the standard model may be adapted to achieve better performance.

METHODS

Selected key CARP event model probabilities are modified based on information relating to changes in the effectiveness of CARPs from clinical trial evidence and an awareness of trends in policy and practice of CARPs. These modified model probabilities and the ones obtained by standard methods are used as inputs in our Markov simulation model.

RESULTS

The projected numbers of CARPs in the population of Western Australia over 1995-99 only improve marginally when modifications to model probabilities are made to incorporate an increase in effectiveness of PCI procedures. However, the projected numbers improve substantially when, in addition, further modifications are incorporated that relate to the increased probability of a PCI procedure and the reduced probability of a CABG procedure stemming from changed CARP preference following the introduction of PCI operations involving stents.

CONCLUSION

There is often knowledge and sometimes quantitative evidence of the expected impacts of changes in surgical practice and procedure effectiveness and these may be used to improve forecasts of future requirements for CARPs in a population.

A Markov simulation model for analyzing and forecasting the number of coronary artery revascularization procedures in Western Australia

PURPOSE

A Markov chain Monte Carlo simulation model was developed to analyze and forecast the numbers of coronary artery bypass graftings, percutaneous coronary interventions (PCIs) , incident coronary heart disease (CHD) events, and CHD deaths for different age and sex groups in the population of Western Australia (population approximately 1.7 million).

METHODS

The Western Australian health information system contains linked records of all hospital admissions and deaths for individuals from 1980 to the present. This system allows the separation of the population into groups according to CHD/coronary artery revascularization procedure history and also allows the estimation of event probabilities directly from population-level data.

RESULTS AND CONCLUSIONS

The results for the 1990 Western Australian population over the period 1990 to 1994 and the 1995 population over the period 1995 to 1999 indicated that the Markov model fits well and produces good forecasts under "stable" conditions. The model can also be useful in ascertaining the impact of system changes, such as the widespread introduction of stents in PCI operations in 1995.

Coronary revascularization in the community. A population-based study, 1990 to 2004

OBJECTIVES

We sought to examine temporal trends in the utilization of coronary revascularization in a geographically defined population.

BACKGROUND

Earlier reports on revascularization utilization focused on inpatient settings and did not distinguish incident from recurrent procedures. Furthermore, little is known on age- and gender-specific trends. Finally, longitudinal data on the utilization and results of coronary angiography as explanatory factors for the changing revascularization practice are lacking.

METHODS

Data integrating diagnostic and therapeutic coronary procedures performed in Olmsted County (Minnesota) between 1990 and 2004 were analyzed. Standardized rates were calculated applying the direct method and temporal trends compared using Poisson regression models.

RESULTS

Revascularization utilization increased by 24% during the study (95% confidence interval [CI] 5% to 46%), but the trends diverged by procedure type, with a sustained increase (69%, 95% CI 43% to 101%) for percutaneous coronary interventions (PCI) contrasting with a stabilization, then decline (-33%, 95% CI -16% to -47%) for coronary artery bypass grafting (CABG). For PCI, although the use increased in all categories, greater increases were noted in the elderly, in women, and for recurrent procedures. No such patterns were detected for CABG. Angiography use remained stable, and the rate of 3-vessel and/or left main disease declined (-22%, 95% CI -8% to -33%).

CONCLUSIONS

Over the 15-year period, revascularization increased in the community with a large increase in PCI partially offset by a decrease in CABG. More PCIs are performed in women and the elderly and for recurrent disease. These changes occurred within the context of a decline in multivessel disease and thus likely reflect the natural history of coronary artery disease.

Coronary artery bypass graft surgery trends in New South Wales, Australia

OBJECTIVE

The main objective of this study was to assess the trends in coronary artery bypass graft (CABG) rates in New South Wales (NSW), Australia over a 12-year period beginning in mid-1990. These rates were examined in relation to the patients' age, gender, complications and length of stay in the hospital.

METHODS

Data pertaining to the CABG surgeries performed among 72668 patients were extracted from the hospital inpatient statistics of the NSW Department of Health. The study covered all public and private hospitals in NSW. The indirect standardization technique and logistic regression modelling were used to analyse the data.

RESULTS

CABG rates increased with age, peaked in the age range 65-79 years and then declined with age. The median age of the patients showed an increasing trend. While women were less likely to have a CABG, they were substantially older than men at the time of surgery. The predictors of extended post-surgery length of stay were age, insulin-dependent diabetes, acute and chronic renal failure, congestive heart failure, pulmonary disease and having more than three vein grafts.

CONCLUSION

An increasing trend in older patients indicates the improvements in skills of cardiothoracic surgeons and the advancement in technology, which have enabled the doctors to treat those patients who were unable to have the surgery previously.

Trends in two year risk of repeat revascularisation or death from cardiovascular disease after coronary artery bypass grafting or percutaneous coronary intervention in Western Australia, 1980-2001

AIMS

To investigate whether, over the 21 year period 1980-2001, there had been a reduction in the risk of repeat revascularisation or death from cardiovascular disease in the cohort of all patients who were treated by coronary revascularisation in Western Australia.

SETTING

State of Western Australia.

PATIENTS

All patients treated by coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) between 1980 and 2001.

DESIGN

Cohort study.

MAIN OUTCOME MEASURES

Risk of repeat coronary artery revascularisation procedures (CARP) and risk of death from cardiovascular disease after first CARP.

RESULTS

After a CABG procedure, the two year risk of repeat revascularisation remained low (less than 2%) across the period 1980-2001. For PCI, however, this risk declined significantly from 33.6% in 1985-9 to 12.4% in 2000-1. The risk of death from cardiovascular disease after a CARP declined by about 50% between 1985 and 2001.

CONCLUSIONS

Outcomes such as the risk of repeat revascularisation and the risk of death from cardiovascular disease have improved significantly for patients who underwent CARPs across the period 1980-2001. This has occurred despite an increasing trend in first CARP rates among older people and those with a recent history of myocardial infarction.