Untargeted metabolomic analysis of coronary artery disease patients with diastolic dysfunction show disturbed oxidative pathway.

INTRODUCTION: Left ventricular diastolic dysfunction (LVDD) is common in patients with coronary artery disease (CAD) with prevalence estimates of 34% and constitutes a predictor of all-cause mortality. Although diastolic dysfunction is induced by myocardial ischemia and has been shown to alter the clinical course, the role of coronary artery disease in the diastolic dysfunction and its progression into heart failure has not been completely elucidated. OBJECTIVE: The present study was conducted to identify possible metabolites in coronary artery disease patients that are differentially regulated in patients with diastolic dysfunction. METHODS: The serum of CAD (n = 75) patients and young healthy volunteers (n = 43) were analysed by using gas chromatography mass spectrometry (GC-MS) technique. Pre-processing of data results in 1547 features; among them 1064 features were annotated using NIST library. RESULTS AND CONCLUSION: Fifteen metabolites were found to be statistically different between cases and control. Variation in metabolites were identified and correlated with several clinically important echocardiography parameters i.e. LVDD grades, ejection fraction (EF) and E/e' values. The results suggested that metabolic products of fatty acid oxidation and glucose oxidation pathways such as oleic acid, stearic acid, palmitic acid, linoleic acid, galactose, pyruvic and lactic acids are predominantly up regulated in patients with coronary artery disease and severity of diastolic dysfunction appears to be linked to increase in fatty acid oxidation and inflammation. The metabolic fingerprints of these patients give us an insight into the pathophysiological mechanism of diastolic dysfunction in coronary artery disease patients although it did not identify validated novel markers.

The frequency of heparin induced thrombocytopenia in patients undergoing elective cardiac bypass surgeries.

OBJECTIVE: To determine the frequency of Heparin Induced Thrombocytopenia (HIT) in patients undergoing elective cardiac bypass surgeries and to observe the platelets evolution post surgically in these patients. METHOD: A prospective study was designed and 100 unselected consecutive patients undergoing elective cardiac bypass surgery were enrolled and evaluated. The clinical and laboratory details were noted before and after surgery. Their platelet counts were observed from day 0 (prior to surgery) to day 5 post operatively. Particle gel immunoassay was used to demonstrate the presence of antibodies against heparin-platelet factor 4 complexes. RESULTS: There were 86 males and 14 females with median age of 59 and 53.5 years respectively. Marked platelet count variation was detected during post operative period in all patients (n=100) ranging from 23 +/- SD 186.73 to 389 +/- 84.12 X 109/L. However, 20 patients showed >50% drop on day 5 and seven of these also showed seroconversion. The clinical scoring for HIT was found to have a good negative predictive value. Thromboembolic complications were not observed in any of our patients. CONCLUSIONS: HIT is prevalent to a significant extent in patients after cardiac surgery in our clinical setting though it mostly remains undetected and is an under-diagnosed entity.

Coronary artery bypass grafting in South Asian patients: Impact of gender.

BACKGROUND: Outcomes following Coronary artery bypass grafting (GABG) vary between genders, with females having a higher postoperative mortality than males. Most of the studies are on Caucasian or mixed population and it is postulated that Asian population and in particular women have higher morbidity and mortality. In this study we have compared outcomes of elective CABG in men and women of South Asian origin in terms of morbidity and mortality. METHODS: From January 2006 to December 2012, 1970 patients underwent isolated elective CABG at the Aga Khan University Hospital, Pakistan were selected. The prospectively collected data was analyzed retrospectively including univariate and multivariate analysis to find the association of morbidity and mortality. RESULTS: Among the study patients 1664 (85%) were male and 306 (15%) female. Hypertension and diabetes were the most common comorbid conditions seen preoperatively in female patients. Atrial fibrillation and sepsis were the most common postop complications seen in females. In hospital mortality was 3.9% in female underwent CABG as against 0.6% in male. Multivariate analysis showed older age, renal failure, dyslipidemia and prolonged cross clamp time as predictors of postoperative morbidity. Multivariate analysis showed female gender, age and renal failure as predictors of in hospital mortality. CONCLUSIONS: Female gender is an independent risk factor for postoperative mortality following CABG however, female gender is not found to be independent risk factor for morbidity. The trend of higher mortality in female patients was comparable to most studies done on Caucasian patients.

Pericardial fluid and serum biomarkers equally predict ventricular dysfunction.

BACKGROUND: serum level of amino-terminal pro-B-type natriuretic peptide, a cardiac hormone produced by the heart, is elevated in patients with left ventricular dysfunction. The purpose of this study was to compare the abilities of serum and pericardial fluid levels of amino-terminal pro-B-type natriuretic peptide to detect the left ventricular systolic dysfunction determined by echocardiography. METHODS: 50 patients undergoing coronary artery bypass grafting were included in this study. Left ventricular systolic function was assessed using echocardiography before coronary artery bypass grafting. The samples of serum and pericardial fluid were collected during surgery, and amino-terminal pro-B-type natriuretic peptide levels were assessed by an electrochemiluminescence immunoassay. The log value of amino-terminal pro-B-type natriuretic peptide concentrations was calculated. RESULTS: the pericardial fluid levels of log amino-terminal pro-B-type natriuretic peptide were significantly elevated compared to the serum levels in patients with impaired left ventricular systolic function. Both serum and pericardial fluid levels of log amino-terminal pro-B-type natriuretic peptide correlated significantly with left ventricular ejection fraction and end-diastolic and end-systolic volume indices. Furthermore, a paired comparison of receiver operating characteristic curves showed a similar performance of amino-terminal pro-B-type natriuretic peptide levels both in serum and pericardial fluid to discriminate left ventricular systolic dysfunction. CONCLUSION: serum amino-terminal pro-B-type natriuretic peptide levels have comparable diagnostic value for left ventricular systolic dysfunction with its pericardial fluid levels in patients undergoing CABG.

Coronary artery bypass surgery in the elderly: experience of tertiary care hospital.

In the subcontinent, improving life expectancy may increase the number of elderly patients requiring coronary artery bypass. The elderly have a higher risk of mortality, and cost vs benefit is presumed to be unrewarding, leading to a disinclination to operate on such patients. We reviewed the records of patients >or= 70 years old undergoing coronary revascularization in a 10-year period. Between 1995 and 2004, 3,312 coronary bypass operations were performed, including 242 (7.3%) in patients >or= 70 years. Of these, 207 (86%) were male, 73 (30%) had non-elective surgery, and 177 (73%) had a high-risk EuroSCORE. Early postoperative mortality was 8.7% (21/242), and 33 (13.6%) patients experienced morbidity. One-year follow-up of 106 (44%) patients was possible. There were 4 (1.7%) late deaths from noncardiac causes. Death, morbidity, and postoperative functional class were significantly associated with preoperative functional class. Meticulous selection of elderly patients for coronary artery bypass may help maximize the benefits of this surgery.