Research Progress on Epigenetics of Diabetic Cardiomyopathy in Type 2 Diabetes

Diabetic cardiomyopathy (DCM) is characterized by diastolic relaxation abnormalities in its initial stages and by clinical heart failure (HF) without dyslipidemia, hypertension, and coronary artery disease in its last stages. DCM contributes to the high mortality and morbidity rates observed in diabetic populations. Diabetes is a polygenic, heritable, and complex condition that is exacerbated by environmental factors. Recent studies have demonstrated that epigenetics directly or indirectly contribute to pathogenesis. While epigenetic mechanisms such as DNA methylation, histone modifications, and non-coding RNAs, have been recognized as key players in the pathogenesis of DCM, some of their impacts remain not well understood. Furthering our understanding of the roles played by epigenetics in DCM will provide novel avenues for DCM therapeutics and prevention strategies.

Pacemaker Induced Cardiomyopathy: An Overview of Current Literature

: Pacemaker induced cardiomyopathy (PICM) is commonly defined as a reduction in left ventricular (LV) function in the setting of right ventricular (RV) pacing. This condition may be associated with the onset of clinical heart failure in those affected. Recent studies have focused on potential methods of identifying patients at risk of this condition, in addition to hypothesizing the most efficacious ways to manage these patients. Newer pacing options, such as His bundle pacing, may avoid the onset of PICM entirely.

B-type natriuretic peptide levels and its correlation with left ventricular functions and heart failure in patients of acute coronary syndromes

Background: This study was designed to measure levels of B-type natriuretic peptide (BNP) across entire spectrum of acute coronary syndrome (ACS) and to find its correlation with left ventricular functions and heart failure.Methods: We measured BNP levels at baseline in 100 consecutive patients between 24-96 hours after the onset of ischemic symptoms in patients of ACS. Echocardiography was performed in all patients between day 2-5 after the index diagnosis and stabilizing the patients.Results: The BNP levels were raised across the entire spectrum of ACS, with levels (>80 pg/ml) in 32.2% of patients with ST segment-elevation myocardial infarction (STEMI), in 24% with non-ST segment-elevation myocardial infarction (NSTEMI), and in 16.6% with unstable angina (UA) respectively. High BNP levels were associated with greater increase in LV end-systolic volumes (r=+0.545, p<0.001) (LVESV) and end-diastolic volumes (LVEDV) (r=+0.336, p<0.001). There was a negative correlation between BNP levels and left ventricular ejection fraction (LVEF) (r=-0.394, p<0.002). BNP levels were significantly raised (156.0±45.1 vs 57.7±18.3 pg/ml, p<0.02) in patients developing symptomatic clinical heart failure, irrespective of LVEF ≤40%.Conclusions: Integrated use of echocardiography and BNP levels provide powerful incremental assessment of cardiac functions, clinical status, and outcome across the entire spectrum of acute coronary syndromes (ACS). Increased BNP levels are associated with progressive ventricular dilatation, LV-dysfunction, development of clinical heart failure and is associated with poor prognosis in patients of ACS.

Left ventricular function and clinical heart failure after myocardial infarction revascularized with percutaneous coronary intervention - comparison between STEMI and NSTEMI in modern practice

Funding Acknowledgements Type of funding sources: None. Introduction Left ventricular systolic dysfunction (LVSD) is a common consequence of myocardial infarction (MI). Data from historic series identified LVSD in up to 60% of patients post-MI. However, in modern practice, with high-sensitivity cardiac biomarkers leading to early detection of MI and widespread use of early revascularization, the prevalence of LVSD in the acute phase of MI and its impact on subsequent clinical heart failure remains unknown. Purpose To ascertain the prevalence of LVSD on pre-discharge echocardiography and its impact on subsequent clinical heart failure after type 1 MI treated with percutaneous coronary intervention (PCI) in a UK tertiary cardiac centre. Methods A retrospective electronic patient records review of consecutive patients with type 1 MI treated with PCI between January 2016 - December 2017. Patients treated conservatively or with surgical revascularization were excluded. Results 1000 consecutive patients were identified and 948/1000 who had an inpatient echocardiogram prior to discharge were included in this analysis – 413 ST elevation MI (STEMI) and 535 non-ST elevation (NSTEMI). Median door to balloon time for STEMI was 42 minutes (IQR 28-79). Median time from symptom onset to intervention for NSTEMI was 3 days (IQR 1-6). LVSD was defined as left ventricular ejection fraction (LVEF) &lt;50% on transthoracic echocardiogram carried out during the hospital episode. LVSD was significantly more prevalent in patients with STEMI compared to NSTEMI (37.4% vs 17.3%, p &lt; 0.001). Median LVEF was significantly lower in the STEMI population (55%, IQR 45-60) compared to patients with NSTEMI (60%, IQR 54-65), p &lt; 0.001. However, rates of clinical heart failure at index presentation with MI did not vary significantly between STEMI and NSTEMI patients (6.1% vs 4.9%, p = 0.414). In stepwise multivariate regression models: age, peak troponin and previous coronary artery bypass grafting were predictors of LVEF, whereas LVEF and previous MI were predictors of clinical heart failure Patients with LVSD on pre-discharge echocardiography had significantly higher rates of 30-day readmission with heart failure (2.9% vs 0.7%, p = 0.017), 30-day all-cause mortality (6.1% vs 2%, p = 0.001), 30-day cardiac mortality (5.7% vs 1%, p &lt; 0.001) and 2-year all-cause mortality (5.7% vs 1.6%, p = 0.001). However, at 2-years, there was no difference in hospital readmission with heart failure (0.8% vs 0.3%, p = 0.276). There were no significant differences between STEMI and NSTEMI patients for these endpoints. Conclusions Early revascularisation with PCI has led to a reduction in the prevalence of early LVSD post-MI compared to historical data. However, the presence of LVSD remains a powerful predictor of adverse clinical outcomes. Despite lower rates of LVSD on pre-discharge echocardiography in patients with NSTEMI compared with STEMI, the incidence of subsequent clinical heart failure is similar. This however may be underestimated due to survival bias.