Coronary artery disease in young women and men with long-standing insulin-dependent diabetes

Association of T-wave electrocardiogram changes and type 2 diabetes: a cross-sectional sub-analysis of the MASHAD cohort population using the Minnesota coding system

BACKGROUND

Type 2 Diabetes Mellitus (T2DM) has become a major health concern with an increasing prevalence and is now one of the leading attributable causes of death globally. T2DM and cardiovascular disease are strongly associated and T2DM is an important independent risk factor for ischemic heart disease. T-wave abnormalities (TWA) on electrocardiogram (ECG) can indicate several pathologies including ischemia. In this study, we aimed to investigate the association between T2DM and T-wave changes using the Minnesota coding system.

METHODS

A cross-sectional study was conducted on the MASHAD cohort study population. All participants of the cohort population were enrolled in the study. 12-lead ECG and Minnesota coding system (codes 5-1 to 5-4) were utilized for T-wave observation and interpretation. Regression models were used for the final evaluation with a level of significance being considered at p < 0.05.

RESULTS

A total of 9035 participants aged 35-65 years old were included in the study, of whom 1273 were diabetic. The prevalence of code 5-2, 5-3, major and minor TWA were significantly higher in diabetics (p < 0.05). However, following adjustment for age, gender, and hypertension, the presence of TWAs was not significantly associated with T2DM (p > 0.05). Hypertension, age, and body mass index were significantly associated with T2DM (p < 0.05).

CONCLUSIONS

Although some T-wave abnormalities were more frequent in diabetics, they were not statistically associated with the presence of T2DM in our study.

Mortality and extent of coronary artery disease in 2776 patients with type 1 diabetes undergoing coronary angiography: A nationwide study

Background In a modern perspective there is limited information on mortality by affected coronary vessels assessed by coronary angiography in patients with type 1 diabetes. The aim of the present study was to characterise distribution of coronary artery disease and impact on long-term mortality in patients with type 1 diabetes undergoing coronary angiography. Design The design of this research was a nationwide population-based cohort study. Methods Individuals ( n = 2776) with type 1 diabetes undergoing coronary angiography 2001-2013 included in the Swedish National Diabetes Registry and Swedish Coronary Angiography and Angioplasty Registry were followed for mortality until 31 December 2013 (mean 7.1 years). In 79% the indication was stable or acute coronary artery disease. Coronary artery disease was categorised into normal (21%), one- (23%), two- (18%), three- (29%) and left main-vessel disease (8%). Results Mean age was 57 years and 58% were male. Mean diabetes duration was 35 years, glycated haemoglobin was 67 mmol/mol and 44% had normal or one-vessel disease. In multivariate Cox proportional analyses hazard ratio for mortality compared with normal findings was 1.09 (95% confidence interval 0.80-1.48) for one, 1.43 (1.05-1.94) for two, 1.47 (1.10-1.96) for three and 1.90 (1.35-2.68) for left main-vessel disease. Renal failure 2.29 (1.77-2.96) and previous heart failure 1.76 (1.46-2.13) were highly associated with mortality. Standard mortality ratio the first year was 5.55 (4.65-6.56) and decreased to 2.80 (2.18-3.54) after five years. Conclusions In patients with type 1 diabetes referred for coronary angiography mortality is influenced by numbers of affected coronary vessels. The overall mortality rate was higher compared with the general population. These results support early intensive prevention of coronary artery disease in this population.

Pretransplant coronary artery disease associated with worse clinical outcomes in pancreas transplantation

BACKGROUND

Coronary artery disease (CAD) is common in patients with type I diabetes and may be associated with worse outcomes in patients undergoing pancreas transplantation (PT). This study evaluates PT patients to determine the pre transplant prevalence of CAD and assesses the post-transplant outcomes including complications and survival.

METHODS

This study is a retrospective review of PTs from 2003 to 2011. Diagnosis of CAD required cardiac catheterization. Outcomes included: myocardial infarction (MI), stroke, and survival.

RESULTS

There were 405 transplants in 389 patients with median follow-up of 56 months. Pre transplant prevalence of CAD was 19% (n = 74). There was no increased risk of perioperative, 90-d or one-yr mortality for patients with CAD. The CAD group did have increased risk of MI (11% vs. 1%, p < 0.001) and stroke (8% vs. 3%, p = 0.02). Controlling for patient and donor age, and history of CAD, the CAD group had decreased patient survival at five yr (82% vs. 90%, p = 0.09, HR 1.77) by Cox regression.

CONCLUSIONS

Patients with type I diabetes and CAD have increased risk of MI and stroke post-pancreas transplant, with decreased five-yr survival. Patients without CAD and a negative pre transplant cardiac evaluation carry a low risk of post-transplant MI.

Comparative vascular responses three months after paclitaxel and everolimus-eluting stent implantation in streptozotocin-induced diabetic porcine coronary arteries

BACKGROUND

Diabetes remains a significant risk factor for restenosis/thrombosis following stenting. Although vascular healing responses following drug-eluting stent (DES) treatment have been characterized previously in healthy animals, comparative assessments of different DES in a large animal model with isolated features of diabetes remains limited. We aimed to comparatively assess the vascular response to paclitaxel-eluting (PES) and everolimus-eluting (EES) stents in a porcine coronary model of streptozotocin (STZ)-induced type I diabetes.

METHOD

Twelve Yucatan swine were induced hyperglycemic with a single STZ dose intravenously to ablate pancreatic β-cells. After two months, each animal received one XIENCE V® (EES) and one Taxus Liberte (PES) stent, respectively, in each coronary artery. After three months, vascular healing was assessed by angiography and histomorphometry. Comparative in vitro effects of everolimus and paclitaxel (10-5 M-10-12 M) after 24 hours on carotid endothelial (EC) and smooth muscle (SMC) cell viability under hyperglycemic (42 mM) conditions were assayed by ELISA. Caspase-3 fluorescent assay was used to quantify caspase-3 activity of EC treated with everolimus or paclitaxel (10-5 M, 10-7 M) for 24 hours.

RESULTS

After 3 months, EES reduced neointimal area (1.60 ± 0.41 mm, p < 0.001) with trends toward reduced % diameter stenosis (11.2 ± 9.8%, p = 0.12) and angiographic late-loss (0.28 ± 0.30 mm, p = 0.058) compared to PES (neointimal area: 2.74 ± 0.58 mm, % diameter stenosis: 19.3 ± 14.7%, late loss: 0.55 ± 0.53 mm). Histopathology revealed increased inflammation scores (0.54 ± 0.21 vs. 0.08 ± 0.05), greater medial necrosis grade (0.52 ± 0.26 vs. 0.0 ± 0.0), and persistently elevated fibrin scores (1.60 ± 0.60 vs. 0.63 ± 0.41) with PES compared to EES (p < 0.05). In vitro, paclitaxel significantly increased (p < 0.05) EC/SMC apoptosis/necrosis at high concentrations (≥ 10-7 M), while everolimus did not affect EC/SMC apoptosis/necrosis within the dose range tested. In ECs, paclitaxel (10-5 M) significantly increased caspase-3 activity (p < 0.05) while everolimus had no effect.

CONCLUSION

After 3 months, both DES exhibited signs of delayed healing in a STZ-induced diabetic swine model. PES exhibited greater neointimal area, increased inflammation, greater medial necrosis, and persistent fibrin compared to EES. Differential effects of everolimus and paclitaxel on vascular cell viability may potentially be a factor in regulating delayed healing observed with PES. Further investigation of molecular mechanisms may aid future development of stent-based therapies in treating coronary artery disease in diabetic patients.

Long-term type 1 diabetes enhances in-stent restenosis after aortic stenting in diabetes-prone BB rats

Type 1 diabetic patients have increased risk of developing in-stent restenosis following endovascular stenting. Underlying pathogenetic mechanisms are not fully understood partly due to the lack of a relevant animal model to study the effect(s) of long-term autoimmune diabetes on development of in-stent restenosis. We here describe the development of in-stent restenosis in long-term (~7 months) spontaneously diabetic and age-matched, thymectomized, nondiabetic Diabetes Prone BioBreeding (BBDP) rats (n = 6-7 in each group). Diabetes was suboptimally treated with insulin and was characterized by significant hyperglycaemia, polyuria, proteinuria, and increased HbA_1c levels. Stented abdominal aortas were harvested 28 days after stenting. Computerized morphometric analysis revealed significantly increased neointima formation in long-term diabetic rats compared with nondiabetic controls. In conclusion, long-term autoimmune diabetes in BBDP rats enhances in-stent restenosis. This model can be used to study the underlying pathogenetic mechanisms of diabetes-enhanced in-stent restenosis as well as to test new therapeutic modalities.