Complications prior to revascularization among patients waiting for coronary artery bypass grafting and percutaneous transluminal coronary angioplasty

Variables Associated With Cardiac Surgical Waitlist Mortality From a Population-Based Cohort

BACKGROUND

Cardiac surgery waitlist recommendations, which were developed based on expert opinion, poorly predict preoperative mortality. Studies reporting risk factors for waitlist mortality have not evaluated the risks including nonadherence to waitlist benchmarks.

METHODS

In patients who underwent cardiac surgery or died on the waitlist between 2005 and 2015, we used a Fine and Gray competing risk model to identify independent predictors of waitlist mortality in 12,106 patients scheduled for urgent, semiurgent, or nonurgent surgery. The predictive variables were compared with Canadian Cardiovascular Society (CCS) waitlist recommendations using the Akaike information criterion.

RESULTS

A total of 101 (0.8%) patients died awaiting surgery. The median wait times and frequency waitlist deaths among emergent, urgent, semi-urgent, and nonurgent surgery were 0.6, 7.4, 69.0, 55.5 days (P < 0.001) and 6.3%, 0.8%, 0.3%, 0.6% (P < 0.001), respectively. Adherence to CCS waitlist recommendations was higher in patients who died on the waitlist (51.6% vs 70.8%, P = 0.001) and was not predictive of waitlist mortality (hazard ratio 1.48, 95% confidence interval 0.62-0.56). Independent predictors of waitlist mortality were age, aortic surgery, ejection fraction < 35%, urgent surgery, prior myocardial infarction, haemodynamic instability during cardiac catheterization, hypertension, and dyslipidemia. These variables were superior to current CCS guidelines (Akaike information criterion 1251 vs 1317, likelihood ratio test P < 0.001).

CONCLUSIONS

CCS waitlist recommendations were poorly predictive of waitlist mortality and the majority of waitlist deaths occur within recommended benchmarks. We identified variables associated with waitlist mortality with improved clinical performance. Our findings suggest a need to re-evaluate cardiac surgical triage criteria using evidence-based data.

Uncertainty and Health-Related Quality of Life 1 Year After Coronary Angiography

Background Little is known about illness-related uncertainty and decreased health-related quality of life in patients undergoing initial coronary angiography or about the long-term effects of uncertainty.

Objectives To compare patients with and without high levels of uncertainty before angiography and to examine the influence of uncertainty on health-related quality of life 1 year after angiography.

Methods In a prospective, longitudinal study, measurements of perceived control, uncertainty, affective distress, and health-related quality of life were collected from 93 patients before angiography (baseline) and 1 year later. At baseline, patients were classified into high- and low-uncertainty groups by median split. At 1 year, analysis of variance was used to compare health-related quality of life and psychological outcomes in the 2 groups, and multiple linear regression with stepwise entry was used to identify independent determinants of health-related quality of life.

Results Compared with patients with low baseline uncertainty, patients with high baseline uncertainty had higher levels of anxiety and depression and lower levels of perceived control and health-related quality of life 1 year after angiography. Baseline health-related quality of life, uncertainty, and life stress accounted for 54% of the variance in health-related quality of life, even when angiographic outcome was controlled for (P &lt; .001). Baseline uncertainty was independently associated with health-related quality of life (β = −0.25; 95% confidence interval, −9.40 to −0.05; P = .02).

Conclusions At initial angiography, high levels of uncertainty about illness portend negative health-related quality of life outcomes up to 1 year later.

Time to intervention during cardiac interventions. Are we forgetting a confounder?

As we evolve in the field of contemporary cardiothoracic surgery and witness modern applications of new techniques and technology, we need to be careful of how statistical methods are executed. Publications with hidden mediators that are not adequately addressed can lead to biased conclusions, especially when meta-analyzed. Public health policies need to be sure that their statements are as unbiased as possible for correct inference, leading to optimal patient safety and well-being. Careful analysis of hidden mediators is important in studies comparing the effectiveness of procedures and devices. Such analysis is critical in identifying mediators such as waiting time that should be considered when constructing interventions to be evaluated in the next RCT. In particular, RCTs of devices and procedures should always conduct (and report) ITT analysis, capturing all events from the time of randomization forward to control for differential waiting time. Similarly, observational registries and databases should count time zero as the time when patients are first referred for therapy, rather than when they enter a hospital to receive treatment; this would ensure that events during the waiting period are captured.

On the waiting list for possible coronary revascularisation. Symptoms relief during the first year and association between quality of life and the very long-term mortality risk

AIM

To describe: a/ the improvement in quality of life (QoL) among patients on the waiting list for coronary revascularisation and b/ the association between QoL and very long-term mortality.

PATIENTS

All patients on the waiting list for possible coronary revascularisation in western Sweden during one week in September 1990.

METHODS

QoL was assessed at the start of the survey and one year later among patients who both were and were not revascularised. Survival data were gathered for the subsequent 14 years.

RESULTS

From the start, 883 patients were evaluated in the survey. Among patients who were revascularised, an improvement was seen in all the aspects of QoL that were studied during the first year as compared with patients who were not revascularised, in whom only minor changes in QoL were seen during the first year. After one year, there were seven aspects of QoL which were significantly associated with the risk of death during the subsequent 14 years, when adjusting for age, sex, previous history and extent of coronary artery disease. They were: tiredness (OR=1.4), weakness (OR=1.5), lack of energy (OR=1.5), inability to react (OR=1.7), use of sedatives (OR=3.2), dyspnea when dressing (OR=2.1) and chest pain when dressing (OR=1.9).

CONCLUSION

Among patients on the waiting list for possible coronary revascularisation, there was a marked improvement in QoL among those who were revascularised. In a variety of aspects of QoL, an association with the very long-term risk of death was observed.

Quality of life at referral predicts outcome of elective coronary artery angiogram

BACKGROUND

Patients' anxiety and quality of life (HRQL) are affected by waiting for diagnostic tests such as coronary artery angiogram (CATH). It is unknown whether HRQL and psychological status at the time of referral are related to likelihood of coronary artery disease (CAD) as diagnosed by CATH.

PURPOSE

The purposes of this study were (1) to determine patients' anxiety and HRQL at the time of referral for elective CATH and (2) to assess the impact of baseline HRQL on likelihood of CAD.

METHODS

This was a prospective observational study of 1009 patients referred for elective CATH. Questionnaires were mailed to patients within 2 weeks of referral. Packages contained a general HRQL measure (SF-36), a condition-specific HRQL measure (Seattle Angina Questionnaire) and the State-Trait Anxiety Inventory (STAI). Patients returned the baseline questionnaires in a postage-paid envelope.

RESULTS

: Complete data were available for 90.6% of patients (n=914). At baseline, general HRQL was significantly lower than population norms for healthy individuals (p<0.0001), but significantly higher than population norms for patients living with angina (p<0.02). Also at baseline, patients' (n=971) mean state anxiety score on the STAI was 44.3 (SD=13.3), reflecting 'high anxiety'. Logistic regression analysis revealed 3 predictors of angiographically documented CAD: male sex (OR 5.76; CI 3.75-8.84), the SF-36 physical functioning subscale (OR 1.05; CI 1.01-1.07) and older age (OR 2.38; CI 1.48-3.82).

CONCLUSION

At the time of referral for elective CATH patients have high levels of anxiety and poor HRQL. It is possible that patient-rated physical HRQL at the time of referral adds to our ability to triage patients according to urgency ratings.

Treating the right patient at the right time: Access to cardiac catheterization, percutaneous coronary intervention and cardiac surgery

The Canadian Cardiovascular Society Access to Care Working Group was formed with a mandate to use the best science and information available to establish reasonable triage categories and safe wait times for common cardiovascular services and procedures through a series of commentaries. The present commentary discusses the rationale for access benchmarks for cardiac catheterization and revascularization procedures for patients with stable angina, and access benchmarks for cardiac catheterization and surgery for patients with valvular heart disease. Literature on standards of care, wait times and wait list management was reviewed. A survey of cardiac centres in Canada was performed to develop an inventory of current practices in identifying and triaging patients. The Working Group recommends the following medically acceptable wait times for access to cardiac catheterization: 14 days for symptomatic aortic stenosis and six weeks for patients with stable angina and other valvular disease. For percutaneous coronary intervention in stable patients with high-risk anatomy, immediate revascularization or a wait time of 14 days is recommended; six weeks is recommended for all other patients. The target for bypass surgery in those with high-risk anatomy or valve surgery in patients with symptomatic aortic stenosis is 14 days; for all others, the target is six weeks. All stakeholders must affirm the appropriateness of these standards and work continuously to achieve them. There is an ongoing need to continually reassess current risk stratification methods to limit adverse events in patients on waiting lists and assist clinicians in triaging patients for invasive therapies.

A Simple Score to Assess Mortality Risk in Patients Waiting for Coronary Artery Bypass Grafting

BACKGROUND

Independent risk factors for death in patients waiting for elective coronary artery bypass surgery have previously been identified. A prioritization where these factors are considered may potentially reduce waiting list mortality. A simple score based on the risk factors was constructed and validated.

METHODS

A scoring system based on risk factors in 5,864 consecutive patients operated from 1995 to 1999 was constructed. The following factors were included in the score: unstable angina (3 points [p]), left main stenosis (2p), concomitant aortic valve disease (2p), operative risk (0-2p), left ventricular ejection fraction (0-2p), and male gender (1p). The score was retrospectively validated in 5,167 new patients operated from 1999 to 2003. Based on the sum of risk score points, the patients were divided into three risk groups: low risk (0-2p), intermediate risk (3-5p) and high risk (> or = 6p). The risk groups were related to waiting list mortality and clinical priority (imperative, urgent, and routine).

RESULTS

Median waiting time was 33 days. Forty-two patients (0.8%) died while waiting for surgery (5.2 deaths/100 waiting years). Of the patients, 2,406 (47%) were low risk, 1,990 (38%) intermediate risk, and 771 (15%) high risk. Mortality incidence in the high-risk group was fivefold higher than in the intermediate group and 25-fold higher than in the low-risk group (32, 7, and 1.3 deaths/100 waiting years, respectively, p < 0.001 between all groups). Twenty-three percent of the patients in the high-risk group had not been given imperative clinical priority.

CONCLUSIONS

The score system identifies patients with increased risk of death while waiting for coronary artery bypass grafting. The score may be used to facilitate and improve the prioritization process.

Gender differences in coronary artery disease

Coronary artery disease in women is associated with higher morbidity and mortality than in men. The purpose of this article is to summarize recent literature concerning gender-based differences. Specific differences in pathophysiology, traditional and psychosocial risk factors, symptom presentation, treatments, and outcomes between women and men will be reviewed.

Disease progression and adverse events in patients listed for elective percutaneous coronary intervention

OBJECTIVE

To record disease progression and the timing of adverse events in patients on a waiting list for elective percutaneous coronary intervention (PCI).

DESIGN

Observational prospective study.

SETTINGS

A UK tertiary cardiothoracic centre, at a time when waiting lists for PCI were up to 18 months.

PATIENTS

145 patients (116 men, median age 59.5 years) placed on an elective waiting list for PCI between October 1998 and September 1999.

MAIN OUTCOME MEASURES

Adverse events recorded were death, myocardial infarction, need for urgent hospital admission because of unstable angina, and need for emergency revascularisation while waiting for PCI.

RESULTS

During a median follow up of 10 months (range 1-18 months), nine (6.2%) patients experienced an adverse event. Eight (5.52%) patients were admitted with unstable angina as emergencies. One was admitted with a myocardial infarction. Twenty nine (20.0%) patients had significant disease progression at the time of the repeat angiogram before PCI. In 10 (7%), disease had progressed so that PCI was no longer feasible and patients were referred for coronary artery bypass graft. Sixteen (11%) were removed from the PCI waiting list because of almost complete resolution of their anginal symptoms.

CONCLUSION

Adverse coronary events and clinically significant disease progression occur commonly in patients waiting for PCI. Despite the presence of severe coronary lesions, myocardial infarction was rare and no patients died while on the waiting list. Resolution of anginal symptoms was also comparatively common. The pathophysiology of disease progression frequently necessitates a change in the treatment of patients waiting for PCI.

Anxiety and health-related quality of life in patients awaiting elective coronary angiography

OBJECTIVE

The purpose of this study was to document the impact of waiting for first-time elective coronary angiography (CA) on patients' anxiety and health-related quality of life (HRQL).

DESIGN

A prospective, observational inception cohort pretest and posttest design was used.

SETTING

The study was conducted in a tertiary community cardiac center in Toronto, Canada.

MEASURES

Disease-specific HRQL was measured using the Seattle Angina Questionnaire at baseline (Time 1 [T1]) and 1 week before CA (Time 2 [T2]). The association between time on the waiting list and subjects' perceived anxiety was analyzed.

RESULTS

Paired-sample t tests comparing mean anxiety levels at T1 and T2 indicated a statistically significant increase in anxiety levels at T2 that did not seem to be related to the waiting time for CA (P =.000). Comparison of mean Seattle Angina Questionnaire scores at T1 and T2 indicated a trend toward deterioration in HRQL over time.

CONCLUSIONS

Waiting for elective CA may have a negative impact on patients' psychologic status and HRQL. Nursing and clinical interventions to reduce anxiety and improve HRQL are indicated for this population.

Mortality on the waiting list for coronary artery bypass grafting: incidence and risk factors

BACKGROUND

Insufficient capacity for coronary artery bypass grafting results in waiting times before operation, prioritization of patients and, ultimately, death on the waiting list. We aimed to calculate waiting list mortality and to identify risk factors for death on the waiting list.

METHODS

The study included 5,864 consecutive patients accepted for elective coronary artery bypass grafting (78% male; mean age, 66 +/- 9 years). The patients were categorized at acceptance into three priority groups: imperative (39%), urgent (36%), or routine (25%). Waiting list mortality was calculated and compared between groups, and risk factors were identified by Poisson regression.

RESULTS

Median waiting time for the whole population was 55 days. Seventy-seven patients (1.3%) died, corresponding to a mortality rate of 5.8 deaths per 100 patient-years. The mortality rate per 100 patient-years was highest for those in the imperative group, 15.1 deaths, compared with 5.3 deaths in the urgent group and 3.2 in the routine group (p < 0.001). Independent risk factors were male sex (p = 0.032), Cleveland Clinic risk score (p = 0.005), impaired left ventricular ejection fraction (p = 0.007), unstable angina pectoris (p = 0.001), concomitant aortic valve disease (p = 0.002), priority group (p < 0.001), and time after acceptance (p = 0.019). The mortality risk increased with time after acceptance by 11% a month.

CONCLUSIONS

Long waiting lists for coronary artery bypass grafting are associated with considerable mortality. The risk of death increases significantly with waiting time. Sex, unstable angina, perioperative risk, impaired left ventricular function, and concomitant aortic valve disease are independent risk factors and should be considered at triage.

Characteristics and outcomes among patients undergoing coronary artery bypass grafting in western Sweden and Minneapolis-St Paul, Minnesota

BACKGROUND

The purpose of this study was to compare patient selection, operative factors, and survival for coronary artery bypass grafting (CABG) for coronary heart disease in Minneapolis-St Paul (MSP), Minnesota, and Western Sweden (WS).

METHODS AND RESULTS

All patients from WS between 1988 and 1991 (n = 2365) and a 17% random sample of MSP patients between 1985 and 1990 (n = 1659) who underwent CABG surgery were studied. CABG was 3 times greater in MSP. MSP patients had significantly more obesity, cigarette smoking, prior CABG, and prior coronary angioplasty. WS patients had more and longer angina pectoris, better left ventricular function, and waited longer from previous acute MI until CABG. WS patients had more internal mammary artery graphs and a shorter aortic cross-clamp time. At discharge, WS patients received more beta-blockers and antiplatelet agents, whereas MSP patients received more calcium channel blockers and digitalis. Age-adjusted mortality rate at 28 days was significantly higher in MSP but not at 3 years. Adjustment for patient characteristics and treatment factors reduced or eliminated these differences.

CONCLUSIONS

Although coronary heart disease rates were higher in WS, age-adjusted CABG rates were 3-fold higher in MSP. Better survival among WS patients was associated with differences in patient selection and clinical and treatment characteristics because MSP patients were more severely ill and at increased risk. Health system characteristics and practice may account for these differences.

Priority points and cardiac events while waiting for coronary bypass surgery

OBJECTIVE

To assess the risk of important cardiac events while waiting for coronary artery bypass surgery (CABG) in relation to the New Zealand priority scoring system; to compare clinical characteristics of patients referred for CABG in New Zealand with those in Ontario, Canada; and to compare the New Zealand priority scoring system for CABG with the previously validated Ontario urgency score.

DESIGN

Analysis of outcomes in a consecutive case series of patients referred for CABG.

SETTING

University hospital.

PATIENTS

All 324 patients from Christchurch Hospital wait listed for isolated CABG between 1 January 1994 and 31 December 1995.

MAIN OUTCOME MEASURES

Death, myocardial infarction, and unstable angina while waiting for CABG; waiting time to surgery.

RESULTS

Clinical characteristics at referral were very similar, but median waiting time was longer in New Zealand than in a large Canadian case series (212 days v 17 days). While waiting for elective CABG, 44% (114/257) of New Zealand patients had cardiac events: death 4% (13/257), non-fatal myocardial infarction 6% (16/257), readmission with unstable angina 34% (87/257). Priority scores did not predict cardiac events while waiting for CABG. Indeed, death or non-fatal myocardial infarction occurred in 4% (3/76) and 8% (6/76), respectively, of those with priority scores < 35. These people are no longer eligible for publicly funded surgery in New Zealand.

CONCLUSIONS

Very long waiting times for CABG are associated with frequent cardiac events, at considerable cost to both patients and health care providers. Priority scores may facilitate comparison between countries but such scores did not predict clinical events while waiting.

Chronic infection in the aetiology of atherosclerosis--focus on Chlamydia pneumoniae

An inflammatory basis to atherosclerosis is now accepted. It remains plausible (but unproven) that common infectious agents may contribute to the inflammatory signal, and hence the development (and/or progression of atherosclerosis and its clinical sequelae. Of the candidate microorganisms implicated, Chlamydia pneumoniae has emerged as the most likely pathogen to have a casual role. Evidence for this is based on sero-epidemiological, pathological and laboratory-based evidence, in addition to early animal models and small-scale antibiotic studies. A past decade of research has now culminated in prospective antibiotic intervention trials in coronary heart disease to be conducted. The results of these studies should help to finally determine whether infection with C. pneumoniae is a pathogenetic factor in atherosclerosis, and whether antibiotic therapy has a role in the secondary prevention of coronary heart disease.