Effects of heart failure and diabetes mellitus on long-term mortality after coronary revascularization (from the BARI Trial)

Comparing clinical outcomes in patients with diabetes undergoing coronary artery bypass graft and percutaneous coronary intervention in real world practice in Iranian population

Background

Coronary artery bypass graft (CABG) is generally regarded as one the treatment options for coronary artery disease (CAD) in patients with diabetes. In recent years, with the advent of drug-eluting stents (DES), percutaneous coronary intervention (PCI) was introduced as a suitable alternative for CABG. The aim of this study was to compare the incidence of major adverse cardiac and cerebrovascular event (MACCE) during mid-term period in patients with diabetes treated with 2 revascularization strategies.

Methods

This historical cohort study was conducted on 750 consecutives patients with diabetes in a single cardiovascular center from July 2009 to March 2012 in Iran. We included previously known case of DM treated with antidiabetic medications (with or without end organ damage) and patient with preoperational evaluation FBS test > 126 (not on the day of the surgery) who were revascularized by 2 strategies. We excluded those patients whose follow-up was not possible.

Results

Finally, out of 697 eligible patients, 355 patients underwent a CABG and 342 underwent a PCI: 53 patients were lost to follow-up (27 in CABG and 26 in PCI groups). The mean follow-up time was 900.68 ± 462.03 days in the CABG and 782.60 ± 399.05 in PCI groups. There were 17 (9.13%) cardiac deaths in the CABG group and 8 (4.45%) in the PCI group; this difference was not significant (P = .11). There was 14 (7.58%) cerebrovascular accident in the CABG group and 4 (2.31%) in the PCI group; this difference was significant (P = .04). Moreover, the frequency of the target vessel revascularization in the CABG and PCI groups was 6 (3.32%) and 31 (17.11%) (P < .001), respectively. Myocardial infarction in the CABG group was 5 (2.77%) and 14 (7.86%) in the PCI group (P = .009). Finally, the frequency of MACCE in the CABG and PCI groups was 41(20.70%) and 47(24.16%) respectively; this difference was not statistically significant (P = .195).

Conclusion

Patients with CABG in this study experienced more CVA, while the frequency of TVR and non-fatal MI was higher in the PCI arm.

Impact of perioperative glycemic control strategy on patient survival after coronary bypass surgery

BACKGROUND

Glycemic control in the perioperative period decreases mortality and morbidity, but data are scarce with regard to the effects of glucose control approaches on survival. We assessed long-term survival in patients treated with 2 strategies of glucose control after first-time isolated coronary artery bypass graft.

METHODS

In a previously published trial, patients were prospectively randomized to strict (90-120 mg/dL) or liberal (121-180 mg/dL) glucose control protocols. The aim of this study was to assess long-term data on survival and health-related quality of life based on the original prospective randomized study population.

RESULTS

No differences were found in cumulative survival between the strict (95.5%) and liberal (93.5%) target range groups (log-rank = 0.32, p = 0.57) over a mean follow-up of 40.0 ± 4.4 months. Physical health-related quality of life significantly improved in all patients from baseline to 6 months after surgery (F = 17.73, p < 0.001), and there were no differences in improvement of health-related quality of life between the 2 target range groups (F = 0.15, p = 0.70).

CONCLUSIONS

These results support our previous findings and indicate that a liberal glycemic control strategy after coronary artery bypass leads to survival rates and improvements in health-related quality of life that are similar to those achieved with a strict target range. In addition, the liberal strategy is superior in glucose control and target range management.

Association of diabetes mellitus with myocardial collagen accumulation and relaxation impairment in patients with dilated cardiomyopathy

AIMS

To assess the effects of diabetes mellitus (DM) on myocardial collagen accumulation, myocardial relaxation, and prognosis in patients with dilated cardiomyopathy (DCM).

METHODS

A total of 102 consecutive DCM patients with a New York Heart Association functional class of I or II were enrolled. Patients were allocated to two groups on the basis of the presence (DCM+DM group, n = 30) or absence (DCM-DM group, n = 72) of DM. Cardiac catheterization performed and left ventricular pressure were measured in all patients. The pressure half-time (T(1/2)) was determined as an index of myocardial relaxation function. Endomyocardial specimens were subjected to histological analysis.

RESULTS

The T(1/2) was significantly longer (P < 0.001) and the collagen volume fraction was significantly greater (P = 0.018) in the DCM + DM group than in the DCM-DM group. Multivariate analysis showed that DM was significantly associated with increased incidence of cardiac events (hazard ratio, 3.7; 95% confidence interval, 1.05 to 13.16; P = 0.03).

CONCLUSIONS

The prognosis of DCM patients with DM was worse than that of those without DM. Impairment of myocardial relaxation, increased myocardial fibrosis, and mitochondrial degeneration associated with DM may underlie this difference.

ALDH2 genetic polymorphism and the risk of type II diabetes mellitus in CAD patients

The prevalence of type II diabetes mellitus (T2DM) in coronary artery disease (CAD) patients has been steadily increasing, especially in East Asian countries. Although many studies have suggested that certain genetic variants may predispose to the development of T2DM, very few studies investigated the genetic link with T2DM in CAD patients of East Asia. In this study, we investigated the relationship between Glu504Lys polymorphism in the acetaldehyde dehydrogenase 2 (ALDH2) gene, a key enzyme of alcohol metabolism, and the risk of having T2DM in Chinese Han CAD patients. We enrolled 542 CAD patients (180 women and 362 men) and 309 CAD-/DM- subjects (152 women and 157 men). T2DM was confirmed in 47.4% of CAD patients. Logistic and linear regression analyses showed that ALDH2 mutant genotypes ((*)1/(*)2 and (*)2/(*)2) were an independent risk factor for both T2DM in female CAD patients, even after controlling for alcohol consumption (OR=1.95, P=0.043), and fasting plasma glucose (FPG) in CAD-/DM- women (P=0.015), whereas the association with FPG disappeared after controlling for high-sensitivity C-reactive protein, a classic inflammatory biomarker. However, there was no relationship between the ALDH2 genetic polymorphism and T2DM or FPG in men. These findings suggest that the ALDH2 polymorphism is associated with an increased risk of T2DM in female CAD patients, and this association could be causal on the basis of the association between the polymorphism and FPG, which is partly explained by an increased inflammatory status. These findings will benefit the screening and treatment of a high-risk population in East Asians.