A study of prevalence of silent coronary artery disease in asymptomatic type II diabetes mellitus

Background: Cardiovascular disease is a major cause of morbidity and mortality in diabetics. However diabetic patients do not present with typical anginal symptoms or may be even asymptomatic and silent coronary artery disease (CAD) is prevalent in diabetics. Moreover silent CAD is not different from symptomatic CAD with respect to prognosis and adverse effects. Aim: The study was done to demonstrate the prevalence of silent myocardial ischemic changes in asymptomatic type 2 diabetes mellitus patients with normal resting ECG by doing a stress exercise test. Methodology: This descriptive study was done in 100 patients with type 2 diabetes more than 2 years who did not have any history of cardiovascular disease or symptoms. Detailed history was taken and investigations such as HbA1c, fasting and postprandial blood sugar, serum creatinine, urine examination were done. Resting ECG, Echocardiogram was found to be normal and they were subjected to a treadmill test. Results: Among the 100 participants 18 persons (18%) had positive ECG findings in treadmill test. A positive association was found between the duration of diabetes and prevalence of positive treadmill test. Conclusion: There is significant prevalence of silent CAD in diabetic patients and they tend to present with advanced disease at presentation and have poorer prognosis compared to non diabetic population. Hence it is necessary to screen early for silent CAD in diabetics to improve disease outcomes.

Silent coronary artery disease in type 2 diabetes: a narrative review on epidemiology, risk factors, and clinical studies

Silent coronary artery disease (CAD) is one of the manifestations of heart disease that particularly affects subjects with type 2 diabetes mellitus (T2DM). From a clinical point of view, silent CAD represents a constant challenge for the diabetologist, who has to decide whether a patient could or could not be screened for this disease. In the present narrative review, several aspects of silent CAD are considered: the epidemiology of the disease, the associated risk factors, and main studies conducted, in the last 20 years, especially aimed to demonstrate the usefulness of the screening of silent CAD, to improve cardiovascular outcomes in type 2 diabetes.

Renal Function, Albumin-Creatinine Ratio and Pulse Wave Velocity Predicts Silent Coronary Artery Disease and Renal Outcome in type 2 Diabetic and Prediabetic subjects

Aims:: To evaluate the incidence of coronary artery disease (CAD) and the relationship between urinary albumin-creatinine ratio, glomerular filtration rate (GFR) and PWV in type 2 DM with silent CAD. Methods:: We analyzed 92 individuals (44 male), 49 (60±7y) type 2 DM non-insulin dependents and 43 prediabetics (43±4y), with Grade I-II hypertension and no symptoms of CAD. All type 2 DM patients were under antidiabetic treatment with an A1C hemoglobin between 5.5 and 6.5%. Every patient underwent a myocardial perfusion SPECT scan. In those subjects with ischemic patterns, a coronary angiography was performed. In addition, a PWV, glomerular filtration rate, and ACR were evaluated. Statistics: mean±SEM, and ANOVA among groups. Results:: 48.59% of DM2 and 25.58% of GI patients had silent coronary artery disease. DM2 and GI patients with CAD had higher ACR and PWV and reduced GFR. DM2 and GI showed a negative relationship between GFR and ACR. Moreover, this relation was also observed in different levels of GFR (>60 ml/min and <60ml.min (p<0.05) in patients with CAD, suggesting a cardio-renal interaction in DM2. Conclusions:: Higher PWV, lower GFR and ACR predict the incidence of CAD in DM2. Dysglycemic individuals also represent a group of higher risk for coronary artery disease with similar predictors showed in DM2. Diabetic and prediabetics, still develop renal microalbuminuria. Thus, PWV seems to represent a reliable marker of renal impairment and coronary artery disease.

Old unsolved problems: when and how to treat silent ischaemia

Silent myocardial ischaemia (SMI) is defined as objective evidence of ischaemia without angina (or equivalent symptoms) in the presence of coronary artery disease, differing from silent coronary artery disease. Silent myocardial ischaemia represents the majority of episodes of myocardial ischaemia at Holter monitoring. During transient myocardial ischaemia, the symptoms appear after the contraction anomalies of the left ventricle and after the ECG changes. The cause of silent myocardial ischaemia is still not well established. The severity and duration of ischaemia have been theorized as important elements in the SMI mechanism. Another possible mechanism responsible for SMI is represented by changes in the perception of painful stimuli with an increased pain threshold. Finally, a neuronal dysfunction of the diabetic, in post-infarction or a cardiac neuronal ‘stunning’ could play a role in SMI. In the pre-stent era, the SMI was associated with a worse prognosis. In patients with diabetes mellitus, SMI seems to be more represented because autonomic dysfunction is present in this category of patients. In conclusion, SMI is more frequent than symptomatic ischaemia. However, despite the presence of countless studies on the subject, it is not clear today whether medical therapy has equalized the risk and what the real prognosis of SMI is.

1203Typical atrial flutter is a manifestation of previously silent coronary artery disease

Background Long-term mortality after ablation of typical atrial flutter has been found to be increased two fold in comparison to atrial fibrillation ablations through a period of five years with unclear mechanism. Methods We analysed 189 consecutive patients who underwent ablation for typical atrial flutter (AFL), in which the incidence of atrial flutter was the first manifestation of cardiac disease. According to clinical standards of our center, the routine recommendation was to evaluate for CAD by invasive angiogram or CT-scan. We compared the AFL patients to 141 patients with paroxysmal atrial fibrillation (AFIB) without known structural heart disease who underwent ablation in the same period and who had routine coronary angiograms performed. Results Out of 189 patients who presented with AFL, coronary status was available in 152 patients (80.4%). Both groups were balanced for mean age (64.9 years in AFL vs. 63.2 years in AFIB; p=0.15), body-mass-index (BMI; 28.8 vs. 28.5 kg/m2; p=0.15), CHA2DS2-VASc-Score (2.20 vs. 2.04; p=0.35), smoking status (22.2% smokers vs. 28.4%; p=0.23) and renal function (GFR >60 ml/min in 96.7% of all patients vs. 95.7%; p=0.76). There were significantly lower values for left-ventricular ejection fraction (52.5% vs. 59.7%; p<0.001), female sex (17.0% vs. 47.5%; p<0.001), hyperlipidemia (37.9% vs. 58.9%; p<0.001) and family history of cardiovascular disease (15.0 vs. 31.9%; p=0.001) in the AFL vs. AFIB cohorts. CAD with stenoses >50% was found in 26.3% of all patients with available coronary status in AFL and in 7.0% in AFIB (p<0.001). CAD with stenoses >75% in 16.4% in AFL whereas only in 1.4% in AFIB (p<0.001). Multivessel disease was detected in 10.5% in AFL and 0.7% in AFIB (p<0.001). After correction for age, LVEF, BMI, CHA2DS2-VASc-Score and it's individual components, smoking status, hyperlipidemia and family history of cardiovascular disease, there was a more than five-fold increase in the likelihood of CAD with stenosis >50% in AFL as compared to AFIB (OR 5.26). A multivariate analysis was performed in the AFL group. Patients with clinically relevant stenoses (>75%) were older (70.6 years vs. 63.8 years; p=0.001), had a higher number of risk factors (3.08 vs. 2.24; p≤0.0016) and a higher CHA2DS2-VASc-Score (3.20 vs 2.00; p<0.0001). With logistic regression, significant CAD could be predicted by higher values for CHA2DS2-VASc-Score with an exponential rise to a pretest-probability of 42.1% at a value of 4 points. Odds ratios of CAD with AFL vs AFIB Discussion This data suggests that typical atrial flutter constitutes a manifestation for previously asymptomatic CAD. Due to the inclusion criteria, CAD has to be considered silent and stable in most of the patients. Therefore, the presence of typical atrial flutter in formerly healthy patients should raise suspicion of otherwise silent CAD and initiate further investigations and risk-stratification with particular emphasis on the individual CHA2DS2-VASc-Scores.

Clinical Value of Circulating Microribonucleic Acids miR-1 and miR-21 in Evaluating the Diagnosis of Acute Heart Failure in Asymptomatic Type 2 Diabetic Patients

To investigate whether the circulating miR-1 (microRNA-1) and miR-21 expression might be used in the diagnosis of heart failure (HF) and silent coronary artery disease (SCAD) in asymptomatic type 2 diabetes mellitus (T2DM) patients and to explore the relationship of these miRs with N-terminal pro-brain natriuretic peptide (NT-proBNP) and galectin-3. One hundred thirty-five consecutive patients with T2DM and 45 matched control subjects were enrolled in the study. This study consisted of the following four groups: control group (mean age: 60.23 ± 6.27 years, female/male (F/M): 23/22); diabetic group (DM) (mean age: 61.50 ± 5.08, F/M: 23/22); DM + SCAD group (mean age: 61.61 ± 6.02, F/M: 20/25); and DM + acute HF group (mean age: 62.07 ± 5.26 years, F/M: 20/25). miR-1 was downregulated in the DM, CAD + DM and HF + DM groups by 0.54, 0.54, and 0.12 fold as compared with controls, respectively. The miR-1 levels were significantly lower in HF + DM than DM with 0.22 fold changes (p < 0.001); and in patients with CAD + DM group with 0.22 fold changes (p < 0.001). Similarly, miR-21 was overexpressed in patients with DM, CAD + DM, and HF + DM with 1.30, 1.79 and 2.21 fold changes as compared with controls, respectively. An interesting finding is that the miR-21 expression was significantly higher in the HF + DM group as compared with the CAD + DM group; miR-1 was negatively correlated with NT-proBNP (r = −0.891, p < 0.001) and galectin-3 (r = −0.886, p < 0.001) in the HF + DM group; and miR-21 showed a strongly positive correlation with (r = 0.734, p < 0.001) and galectin-3 (r = 0.764. p < 0.001) in the HF + DM group. These results suggest that the circulating decreased miR-1 and increased miR-21 expression are associated with NT-proBNP and galectin-3 levels in acute HF + DM. Especially the miR-21 expression might be useful in predicting the onset of acute HF in asymptomatic T2DM patients. The miR-21 expression is more valuable than the miR-1 expression in predicting cardiovascular events of acute HF and the combined analysis of miR-21 expression, galectin-3, and NT-proBNP can increase the predictive value of miR-21 expression.