Late-onset heart failure as a mechanism for adverse long-term outcome in diabetic patients undergoing revascularization (a 13-year report from the Lady Davis Carmel Medical Center registry)

Genetics, coronary artery disease, and myocardial revascularization: will novel genetic risk scores bring new answers?

Both percutaneous coronary intervention (PCI) and coronary artery bypass graft surgery (CABG) are options for revascularization in multi-vessel coronary artery disease (CAD). However, the best form of revascularization remains controversial. Results from clinical trials (FREEDOM, SYNTAX, NOBLE, EXCEL) have identified factors related to CAD severity such as diabetes and SYNTAX score as indicators that patients may have better outcomes with CABG compared to PCI. Nevertheless, the discovery of other predictors of optimal revascularization therapy is necessary to improve decision-making and personalize the treatment of multi-vessel CAD. Genome-wide association studies have identified numerous previously unknown DNA variants that increase predisposition for CAD. Recently, a composite polygenic risk score has been developed to better assess the relative contribution of multiple SNPs and quantify overall genetic risk for CAD. High polygenic risk score is associated with increased coronary events and greater benefit from statin therapy in large observational studies. This effect is independent from traditional cardiovascular risk factors. At the same time, randomized clinical trials have shown that CAD severity is a determinant of optimal revascularization treatment. It remains unknown whether polygenic risk score is robustly associated with increased CAD severity at presentation, and whether this score can be used to identify patients who will show greater benefit from revascularization with CABG or with PCI.

Genetics of coronary artery disease: should they impact the choice of revascularization?

PURPOSE OF REVIEW

Patients with multivessel coronary artery disease (CAD) may undergo revascularization by either percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery (CABG). This review will discuss the use of polygenic risk scores for risk-stratification of patients with multivessel CAD in order to guide the choice of revascularization.

RECENT FINDINGS

A 57-single nucleotide polymorphism (SNP)-polygenic risk score can accurately risk-stratify patients with CAD and identify those who will receive greater benefit from statin therapy. The most recent genomic studies reveal 243 different SNPs are now significantly associated with CAD. Randomized clinical trials comparing PCI vs. CABG (FREEDOM, SYNTAX, NOBLE, EXCEL) have uncovered factors related to CAD severity (diabetes, SYNTAX score) are critical determinants of outcomes after revascularization.

SUMMARY

There is a need to discover predictors of outcomes after PCI vs. CABG to improve clinical decision-making in multivessel CAD. High polygenic risk score is associated with increased CAD severity and better outcomes with statin therapy. Randomized clinical trials indicate CAD severity is associated with better outcomes after CABG compared with PCI. Accordingly, polygenic risk score could also be associated with better outcomes after CABG vs. PCI and used to optimize revascularization for patients with multivessel CAD.

Management of Noncardiac Comorbidities in Chronic Heart Failure

Prevalence of heart failure is increasing, especially in the elderly population. Noncardiac comorbidities complicate heart failure care and are increasingly common in elderly patients with reduced or preserved ejection fraction heart failure, owing to prolongation of patient's lives by advances in chronic heart failure (CHF) management. Common comorbidities include respiratory disease, renal dysfunction, anemia, arthritis, obesity, diabetes mellitus, cognitive dysfunction, and depression. These conditions contribute to the progression of the disease and may alter the response to treatment, partly as polypharmacy is inevitable in these patients. Cardiologists and other physicians caring for patients with CHF need to be vigilant to comorbid conditions that complicate the care of these patients. There is now more guidance on management of noncardiac comorbidities in heart failure, and this article contains a comprehensive review of the most recent updates on management of noncardiac comorbidities in CHF.

Coronary heart disease in patients with diabetes: part II: recent advances in coronary revascularization

Although diabetic patients represent approximately one-quarter of all those undergoing revascularization, their outcomes after revascularization are usually worse compared with non-diabetic patients. We examined the recent advances in percutaneous and surgical revascularization that are relevant to the treatment of diabetic patients. A systematic review of publications in the past 5 years (2000 to 2005) relating to coronary revascularization in diabetes was undertaken. Early and mid-term follow-up of diabetic patients after revascularization indicates that the incidence of myocardial infarction and repeat revascularization are reduced in surgically treated patients compared with those treated by balloon angioplasty alone. Percutaneous coronary intervention (PCI) with bare metal stents has reduced the surgical advantage (for reintervention) in the early-mid-term; however, repeat revascularization in diabetic patients continues to be substantially higher after PCI. Advances in PCI include the use of drug-eluting stents and adjunctive drug therapies, such as abciximab. Glycemic control is an important determinant of outcome after revascularization in diabetic patients, and the impact of tight glycemic control after PCI is currently being investigated in the BARI 2D (Bypass Angioplasty Revascularization Investigation 2 in Diabetes). Improvements in PCI and coronary artery bypass graft surgery are leading to better results in diabetic patients, and clinical trials are presently comparing contemporary PCI with surgery.

The synergistic effect of heart disease and diabetes on self-management, symptoms, and health status

BACKGROUND

Coronary heart disease (CHD) and diabetes may have synergistic effects on symptoms, self-management, and general and cardiac-specific health status.

PURPOSE

We compared symptom distress, self-management difficulties, and general and cardiac-specific health status in patients with CHD by the presence and severity of diabetes.

METHODS

We performed a cross-sectional study of 1013 patients enrolled in the COURAGE trial, with the use of clinical data, the Symptom Distress Scale, the Self-Management Difficulties Scale, the Short-Form 36, and the Seattle Angina Questionnaire.

RESULTS

Patients with diabetes and greater severity of diabetes had worse findings in symptom distress, self-management difficulties, and general and cardiac-specific health status than patients without diabetes.

CONCLUSIONS

A robust effect of diabetes on symptom distress and self-management difficulties was found in patients with CHD. The results from the Seattle Angina Questionnaire illustrate difficulty in attributing physical limitations to specific symptoms or conditions, and show the experience of comorbid conditions to be synergistic. Clinicians' understanding of this synergy and integration of condition-specific care with general treatment and self-management practices are needed.

Coronary revascularization (surgical or percutaneous) decreases mortality after the first year in diabetic subjects but not in nondiabetic subjects with multivessel disease: an analysis from the Medicine, Angioplasty, or Surgery Study (MASS II)

BACKGROUND

It is currently unknown whether revascularization procedures are associated with an improvement in mortality among diabetic subjects, as compared with a more conservative medical treatment.

METHODS AND RESULTS

In MASS II, a total of 611 patients with stable multivessel coronary disease were randomly assigned to medical treatment, surgery, or angioplasty. From these, 190 patients had diabetes (medical, 75 patients; angioplasty, 56 patients; surgery, 59 patients) and comprised the present study population. Mortality rates were analyzed for the entire 5 years of follow-up. Separate analyzes were also performed for mortality at 2 time intervals: during the first year and after the first year of follow-up. We calculated the probability of death conditional on surviving to the start of the interval analyzed. The cumulative 5-year mortality as well as the mortality during the first year of follow-up was not significantly different among treatment groups, both for diabetic and for nondiabetic subjects. Also, during years 2 to 5, the mortality of the 3 treatment groups was not different for nondiabetic subjects. Among diabetic subjects, however, patients randomized to angioplasty or surgery had a significantly lower mortality between years 2 and 5 than those allocated to medical treatment (P=0.039).

CONCLUSIONS

Surgery, angioplasty, and medical treatment appear to be associated with similar mortality rates for non-diabetic subjects. For diabetic subjects, however, coronary revascularization (percutaneous or surgical) significantly decreased the risk of death after the first year and up to 5 years, compared with medical treatment alone.

Heart Failure and Diabetes: Collateral Benefit of Chronic Disease Management

To test the hypothesis that a focus on heart failure (HF) care may be associated with inadequate diabetes care, the authors screened 78 patients (aged 64+/-11 years; 69% male) with diabetes enrolled in an HF disease management program for diabetes care as recommended by the American Diabetes Association (ADA). Ninety-five percent of patients had hemoglobin A1c levels measured within 12 months, and 71% monitored their glucose at least once daily. Most patients received counseling regarding diabetic diet and exercise, and approximately 80% reported receiving regular eye and foot examinations. Mean hemoglobin A1c level was 7.8+/-1.9%. There was no relationship between hemoglobin A1c levels and New York Heart Association class or history of HF hospitalizations. Contrary to the authors' hypothesis, patients in an HF disease management program demonstrated levels of diabetic care close to ADA goals. "Collateral benefit" of HF disease management may contribute to improved patient outcomes in diabetic patients with HF.

Heart failure in diabetic patients: utility of beta-blockade

BACKGROUND

Congestive heart failure (CHF) occurs with increased frequency in patients with diabetes and carries a higher risk of morbidity and mortality compared with nondiabetic persons. Diabetic patients are more likely to suffer from CHF and its consequences because of hypertensive and ischemic heart disease and diabetic cardiomyopathy.

METHODS

Intensive combination therapy, directed at the different aspects of the pathophysiology of CHF in diabetes patients, results in improved outcomes. Improvement of glycemia, reduction of low-density lipoprotein cholesterol levels, tight control of blood pressure, and antiplatelet therapy have been all shown to decrease the morbidity and mortality associated with CHF in diabetic patients. beta-blockade added to angiotensin-converting enzyme (ACE) inhibition has become an increasingly integral component of CHF therapy.

RESULTS

Improved outcome with beta-blockade treatment is due to decreased incidence of both sudden death and pump failure and is of particular benefit to diabetic patients during and after myocardial infarctions complicated by systolic dysfunction.

CONCLUSIONS

Based on retrospective analysis, beta-blocking agents with vasodilating properties may provide additional benefits in diabetic patients because they may improve insulin sensitivity and vasorelaxation.

Differential influence of diabetes mellitus on increased jeopardized myocardium after initial angioplasty or bypass surgery: bypass angioplasty revascularization investigation

BACKGROUND

Data are absent that compare midterm angiographic outcome between patients with and without diabetes after initial percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass graft surgery (CABG). Importantly, diabetes mellitus may differentially influence long-term survival after PTCA or CABG.

METHODS AND RESULTS

Patients with multivessel coronary disease who were previously enrolled in the Bypass Angiopathy Revascularization Investigation to compare initial PTCA versus CABG (n=1829) and who had a reduction in jeopardized myocardium after initial revascularization and at least 1 angiogram during 5-year follow-up were analyzed (n=897). This included 369 CABG-treated patients (16% with diabetes) and 528 PTCA-treated patients (18% with diabetes). The influence of diabetes on angiographic increase in percentage of jeopardized myocardium after initial revascularization with either PTCA or CABG was investigated. Among PTCA patients, the mean percentage increase in total jeopardized myocardium was significantly greater in those with diabetes than in those without at 1-year protocol-directed angiography (42% versus 24%, P=0.05) and on the first clinically performed (unscheduled) angiogram within 30 months (63% versus 50%, P=0.01) but not at 5-year protocol-directed angiography (34% versus 26%, P=0.33). This excess midterm risk associated with diabetes persisted after statistical adjustment. In contrast, among CABG patients, diabetes was not associated with percentage increase in jeopardized myocardium at any angiographic follow-up interval.

CONCLUSIONS

Presence of diabetes differentially influences worsening of jeopardized myocardium after initial PTCA compared with CABG. This differential effect occurs irrespective of whether follow-up angiography is undertaken for clinical or nonclinical purposes.