Coronary risk factors six to 12 months after coronary artery bypass graft surgery

Smoking and cardiac rehabilitation participation: Associations with referral, attendance and adherence

OBJECTIVE

Continued smoking after a cardiac event greatly increases mortality risk. Smoking cessation and participation in cardiac rehabilitation (CR) are effective in reducing morbidity and mortality. However, these two behaviors may interact; those who smoke may be less likely to access or complete CR. This review explores the association between smoking status and CR referral, attendance, and adherence.

METHODS

A systematic literature search was conducted examining associations between smoking status and CR referral, attendance and completion in peer-reviewed studies published through July 1st, 2014. For inclusion, studies had to report data on outpatient CR referral, attendance or completion rates and smoking status had to be considered as a variable associated with these outcomes.

RESULTS

Fifty-six studies met inclusion criteria. In summary, a history of smoking was associated with an increased likelihood of referral to CR. However, smoking status also predicted not attending CR and was a strong predictor of CR dropout.

CONCLUSION

Continued smoking after a cardiac event predicts lack of attendance in, and completion of CR. The issue of smoking following a coronary event deserves renewed attention.

Changes in cholesterol levels in women after coronary artery bypass surgery

OBJECTIVE

To examine the predictors of change in cholesterol levels in a cohort of women between the time of surgery and 1 year after coronary artery bypass graft surgery (CABG).

DESIGN AND SETTING

This study was a prospective, descriptive study held at a Mid-Atlantic tertiary care medical center.

METHODS

Lipid profiles, lifestyle behaviors, and other major coronary risk factors were measured at the time of surgery and again 12 months later from a consecutive convenience sample of 130 women who underwent first-time, isolated CABG.

RESULTS

The sample population was 24% black and 76% white and had a mean age of 65 years and an average of 11 years of education. Although no statistically significant changes in cholesterol levels were observed, a majority (55%) of women had increases in total cholesterol level, whereas 45% had decreased total cholesterol level between baseline and 1 year of follow-up. After controlling for preoperative cholesterol values, a change in cholesterol level was independently predicted by ejection fraction, smoking status, and body mass index. At 1 year, plasma lipoprotein levels were not optimally managed, with high proportions of values exceeding national guidelines for secondary prevention.

CONCLUSIONS

Women continue to have high cholesterol levels after CABG, putting them at high risk for future coronary heart disease events. Effective secondary prevention programs targeting multiple lifestyle behaviors and adequate pharmacotherapy are needed.

Coronary risk factors in women one year after coronary artery bypass grafting

Given the importance of risk factor management to long-term outcome following coronary artery bypass grafting (CABG) and the paucity of information on risk factor changes in women, a study was undertaken to examine the coronary risk factor status of women before and 1 year after CABG. This study was a prospective investigation of 130 women who underwent first-time, isolated CABG between February 1992 and October 1993. Lipid profiles, blood pressure, weight, smoking status, and other lifestyle behaviors were measured at the time of surgery and again 12 months later. The sample was 24% African American and had a mean age of 65 years and an average of 11 years of education. Substantial favorable changes in risk factor status occurred in the prevalence of smoking and the number of cigarettes smoked per day among smokers. Although the women experienced weight loss, 58% continued to be obese, and the self-reported dietary intake of fat, saturated fat, and cholesterol remained above the recommended levels of the National Cholesterol Education Program's Step II diet. Mean systolic and diastolic blood pressures significantly increased, and a substantial number of patients (54%) continued to exhibit hypertension at 1 year. No significant changes in plasma lipid concentrations were observed. At 1 year, one third of the women exceeded recommended levels for triglycerides, 78% for total cholesterol, and 92% for low-density lipoproteins. These findings indicate that women continue to have multiple coronary risk factors after CABG, putting them at high risk for future coronary heart disease events. Healthcare professionals need to target these women for effective secondary prevention.

Coronary risk factor modification in women after coronary artery bypass surgery

In a trial to evaluate the effectiveness of a nurse-directed intervention designed to help patients decrease dietary intake of fat, quit or decrease smoking, and increase exercise, 138 women who underwent coronary artery bypass surgery were randomized to receive special intervention (SI) or usual care (UC). The SI group received a behavioral program based on self-efficacy theory in the home 2 weeks after discharge with regular follow-up. The UC group received routine medical care. Risk factors and lifestyle behaviors were measured at baseline and 1 year after surgery in 116 (84%) women (SI = 59, UC = 57). The SI group decreased their total fat intake from a mean of 38% of calories at baseline to 35% at 1 year, while the UC group increased it from 36% to 38%. The prevalence of smoking decreased from 24% at baseline to 8% at 1 year in the SI group and from 19% to 14% in the UC group. At follow-up, the quit rate in those smoking at baseline was 64% in the SI group, with no new smokers, and 55% in the UC group, with three new smokers. Both groups reported improvement in exercise, with the proportion of women reporting participation in some form of regular exercise slightly higher in the SI group than in the UC group, 54% and 51%, respectively.

Late outcome after coronary artery bypass graft surgery in patients < 40 years old

BACKGROUND

Randomized trials confirm the long-term efficacy of coronary artery bypass graft surgery (CABG), although there are no randomized data in patients < 40 years old. Because these patients have been reported to have an early recurrence of symptoms, the long-term postoperative outcome was examined.

METHODS AND RESULTS

The long-term outcome of patients (n = 221) < 40 years old undergoing CABG at Green Lane Hospital, New Zealand, from 1970 to 1992 was determined. The 30-day mortality rate was 1.8% for initial and 9.5% for redo CABG. The median times to angina or myocardial infarction (recurrent ischemic event), further intervention, and death were 6.0, 9.6, and 14.2 years, respectively. Factors associated with increased late mortality on univariate analysis included end-systolic volume (ESV) > or = 80 mL (P = .004; 10-year mortality 19% versus 39% ESV > or = 80 mL), no internal mammary conduit (P = .01), no lipid-modifying therapy (P = .005), and no postoperative aspirin use (P = .0002); the latter was also associated with increased recurrent ischemic events (P = .04) or increased reintervention (P = .02). On stepwise logistic regression analysis, factors associated with increased late mortality were increasing ESV (P = .004), no internal mammary artery conduit (P = .009), diabetes (P = .04), and no postoperative aspirin (P = .02); the latter was also associated with increased recurrent ischemic events (P = .02). Hypercholesterolemia (> or = 6.5 mmol/L) was present in 65% of patients at presentation and 45% at follow-up.

CONCLUSIONS

To attempt to prevent recurrent ischemia or late death, patients < 40 years old who require CABG should receive internal mammary conduits, aspirin, lipid-modifying therapy, therapy to inhibit ventricular dilatation, and strict diabetes management.

Coronary risk factors in women six months after coronary artery bypass grafting

The coronary risk factor status of women before and after coronary artery bypass grafting has not been fully described. This study was a prospective investigation of 136 women who underwent first-time, isolated coronary artery bypass grafting between February 1992 and October 1993. Major coronary risk factors were measured at the time of surgery and again 6 months later. The sample was 22% black, had a mean age of 64 years, and an average of 11 years of education. Substantial favorable changes in risk factor status occurred in the prevalence of smoking and the number of cigarettes smoked per day among smokers. Although the self-reported dietary intake of fat decreased significantly, the dietary consumption of fat, saturated fat, and cholesterol remained above the recommended levels of the Step II diet and weights remained essentially the same. Mean systolic and diastolic blood pressures significantly increased and a substantial number of patients (59%) continued to exhibit hypertension at 6 months. No significant changes in plasma lipid concentrations were achieved. At 6 months, one third of the women exceeded recommended levels for triglycerides, 85% for total cholesterol, and 92% for low-density lipoproteins. In addition, 34% had high-density lipoprotein levels < 40 mg/dl. Health care professionals need to target these women for effective secondary prevention.

Early and late survival after coronary-artery surgery

Between 1970 and 1985, 1801 patients underwent coronary-artery surgery without associated valvular surgery. Eighty-four per cent of patients were male and the mean (+/- SD) age was 55.7 +/- 8.3 years. Of the patients, 18.7% were from the Coronary Care Unit and 6.5% had diabetes. The hospital mortality rate for the whole group was 3.5%. Patients from the Coronary Care Unit had the highest (8.9%) hospital mortality rate compared with those patients who were not from the Coronary Care Unit (2.1%; P less than 0.001). Other factors which increased the hospital mortality rate significantly were the number of diseased vessels (P less than 0.01), the degree of left main coronary-artery stenosis (P less than 0.001), an earlier year of surgery (P less than 0.01) and female sex (P less than 0.01). After these were taken into account, no other factors (for example, age, preoperative infarction, presence of left-ventricular aneurysm, left-ventricular end-diastolic pressure, diabetes, use of mammary-arterial grafts or the need for endarterectomy) affected the mortality rate. Patients were followed-up for a mean (+/- SD) of 4.4 +/- 2.8 years. The five-year survival rate for all patients was 88% and the 10-year survival rate was 65%. Cox regression analysis showed that the significant indicators of decreased long-term survival were undergoing operation directly from the Coronary Care Unit (P less than 0.001), left main coronary-artery stenosis (P less than 0.01), the number of grafted vessels (P less than 0.01), concomitant surgery for aneurysm (P less than 0.001), year of surgery (P less than 0.01). Seventy-nine per cent of patients were free of angina pectoris at five years after operation. The year of surgery (P less than 0.001) and preoperative myocardial infarction (P less than 0.05) were the best predictors of recurrent angina. In the long term, recurrent angina remains a problem, although this may change with the increased use of mammary-arterial grafts.

Coronary risk factor outcomes following coronary artery bypass surgery

The coronary risk factor status of patients prior to and following coronary artery bypass surgery (CABG) has been poorly investigated. Two consecutive series of CABG patients were surveyed following CABG. One hundred and thirty patients were assessed immediately following CABG and 530 patients were assessed 12-30 months following CABG. For the long-term post-CABG group, over 80% of those who had ever smoked had ceased. Sixty-four per cent of these males and 50% of females were classified as being overweight. Twenty-five per cent of males and 34% of females reportedly had high serum cholesterol (i.e. greater than or equal to 6.5 mmol/L). Comparing these CABG data with age-adjusted National Heart Foundation Risk Factor Prevalence Survey data, there was a higher prevalence of ex-smokers, overweight, hypertension, and elevated cholesterol. It was concluded that on most coronary risk factors, except for smoking, these CABG patients had a worse profile than the general Australian community. This problem warrants further research and the development of appropriate treatment programs.

Lipids and lipoproteins in patients undergoing coronary-artery surgery

Fasting blood samples were obtained from 290 patients who were undergoing elective coronary-artery graft procedures, and cholesterol, triglyceride and high-density lipoprotein cholesterol levels were measured. The 1983 National Heart Foundation of Australia's Risk Factor Prevalence Study was used as a source of age- and sex-matched "control" data. Of these patients, 80% had cholesterol levels of greater than 5.5 mmol/L; in 55% of patients, the level exceeded 6.5 mmol/L. Only 4% of patients who received a graft showed hypertriglyceridaemia alone (triglyceride level, greater than 2 mmol/L). Combined hyperlipidaemia (cholesterol level, greater than 5.5 mmol/L and triglyceride level, greater than 2.0 mmol/L) was present in 52% of subjects. Low-density lipoprotein cholesterol levels exceeded 3.5 mmol/L in 69% of men and in 71% of women. In terms of five 10-year age intervals, mean plasma triglyceride and cholesterol levels were elevated significantly in patients who had undergone a coronary-artery grafting procedure compared with those of subjects in the National Heart Foundation study. The mean high-density lipoprotein cholesterol levels were markedly-lower compared with those of the subjects in the National Heart Foundation study. Of those patients whose plasma cholesterol levels were less than 5.5 mmol/L, 97% of patients had high-density lipoprotein cholesterol levels that were less than the mean level for subjects in the National Heart Foundation study. Thus, a very-high proportion of patients who underwent coronary-artery bypass surgery had lipid abnormalities which required intervention postoperatively.