Variability in lipid profile before and after coronary artery bypass grafting (CABG)

Objective: To investigate changes in total cholesterol, low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, and triglycerides in serum of Pakistani patients before, immediately after and 5 days post CABG.Method: Serum samples from 31 consecutive Pakistani angina patients undergoing CABG at the Aga Khan University Hospital were analyzed for total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides using kit methods.Results: Immediately after CABG, there is a significant decline in the mean levels of serum cholesterol, LDL cholesterol, HDL cholesterol and triglycerides. However, 5 days post CABG, there is a significant increase in the concentrations of total cholesterol (P = 0.01) and LDL cholesterol (P = 0.001) in nondiabetic angina patients (n = 13). Among the diabetic group of patients (n = 18), the levels of total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides went back to the pre-operative levels within 5 days post CABG. Compared to European patients, Pakistani patients tend to have very low levels of HDL cholesterol (24.9 +/- 7.1 mg/dl) and high levels of triglycerides (185 +/- 50 mg/dl) on day 5 post CABG.Conclusion: Since risk of mortality following CABG increases with low level of HDL cholesterol and high level of triglycerides, close monitoring and treatment of high lipid levels of Pakistani patients following CABG is necessary to prevent further coronary events

N-acetyl-B-D-glucosaminidase and inflammatory response after cardiopulmonary bypass

OBJECTIVE: To determine the changes in activity of plasma N-acetyl-beta-D-glucosaminidase, a marker for inflammation as well as renal, pulmonary and cardiac damage and proinflammatory cytokines in patients undergoing coronary artery bypass grafting and find out the relationship between their plasma levels with clinical outcome of patients. STUDY DESIGN: Cross-sectional study. PLACE AND DURATION OF STUDY: The Aga Khan University, Karachi, from January to June 2003. PATIENTS AND METHODS: N-acetyl-beta-D-glucosaminidase (NAG) activity and concentrations of tumor necrosis factor-alpha of (TNFalpha), interleukin 6 (IL-6), interleukin 8 (IL8) and granulocyte-macrophage colony stimulating factor (GM-CSF) were monitored in plasma samples of 12 angina patients undergoing coronary artery bypass grafting (CABG), before, immediately after and 5 days post-surgical procedure. Serum glucose concentrations were also monitored in those patients. Patient\u27s clinical condition was monitored during this time period. RESULTS: No significant increase was observed in plasma NAG activity (a marker of inflammation) or in plasma levels of TNFalpha, IL-6, IL-8 and GM-CSF immediately after surgery, indicating that cardiopulmonary bypass itself does not produce any significant amount of inflammation immediately after CABG. However, 5 days post surgery, there was a significant increase in plasma NAG activity (p=0.001), TNFalpha (p=0.047) and GM-CSF (p=0.045). There was no relationship between plasma NAG activity and clinical outcome because various parameters of renal, cardiac and pulmonary functions, though slightly affected, remained within the normal limits. CONCLUSION: Increased levels of NAG and TNFalpha did not affect clinical outcome. However, data suggest that NAG can be a potential marker for inflammation and end organ damage following CABG. An increase in GM-CSF on day 5 following CABG indicates enhanced body\u27s defense mechanism against infection

Health economics of coronary artery bypass grafts versus percutaneous coronary intervention for revascularization of 3 vessel coronary artery disease in a resource-poor country

Background: Estimates of Health care costs associated with revascularization range from 12 billion dollars to 20 billion dollars each year. Prior studies have revealed that the initial costs associated with Percutaneous Intervention procedure (PCI) are lesser compared to Coronary Artery bypass Graft (CABG) surgery. However, since PCI often requires subsequent revascularization, long-term costs for both these procedures are comparable. Most of these conclusions are based on western studies and thus used with caution in developing countries. This study aims to estimate cost and early outcomes of both these procedures in tertiary care hospital settings in Pakistan. Methods: This is a retrospective study, based on hospital record being reviewed at the Aga Khan University Hospital for evaluation of healthcare costs for both these procedures and their relative cost effectiveness in terms of early outcomes. The study population includes all patients who have undergone CABG surgery or PCI revascularization from January 2011 to December 2013. Findings: Initial findings from the costs incurred at the hospital reveal cost of Coronary artery bypass graft surgery (CABG), single Drug eluting stent (PCI) and single bare metal stent (PCI) as PKR 298,000 PKR 425,000 PKR 325,000 respectively. The costs associated with PCI for revascularization in multi-vessel Coronary artery disease are almost threefold the original price of one single stent. While this is only the direct healthcare cost and not the complete cost estimate for both these procedures, these findings strongly suggest that CABG is far more economical than PCI in local settings. Conclusion: The results of this study would contribute to cost effective management of cardiovascular diseases in Pakistan at tertiary care level hospital settings. In developing countries such evidence is particularly important from the patient and family perspective. In the back drop of the fact that out-of-pocket health expenditure is over 60% of total health expenditure in Pakistan it likely that most of the financial burden of management of DVD is borne by the patient and his family

Cardiac rupture during stress echocardiography

A case of acute cardiac rupture during dobutamine stress echocardiography testing that was performed on the sixth day after admission for an acute inferoposterior myocardial infarction is reported. Following successful surgical repair, the postoperative course was complicated by severe mitral regurgitation secondary to papillary muscle rupture

Skeletal muscle metabolism in heart failure: a 31P nuclear magnetic resonance spectroscopy study of leg muscle

1.The gastrocnemius muscle of seven patients with mild to moderate chronic heart failure and of five healthy control subjects was studied using 31P nuclear magnetic resonance spectroscopy. Spectra were collected at rest and during an incremental, symptom-limited, exercise protocol. Blood flow was measured in the same study during brief interruptions to exercise. 2. The phosphocreatine/(phosphocreatine plus inorganic phosphate) ratio was lower in patients with heart failure than in control subjects at an exercise rate of 1.5 W, although intracellular pH and blood flow were similar. 3. The cytosolic free adenosine 5\u27-diphosphate concentration was markedly increased in patients with heart failure exercising at 1.5 W compared with control subjects exercising at the same workload. 4. Although the maximum workload achieved by patients with heart failure was less than half of that reached by control subjects, the pH and the phosphocreatine/(phosphocreatine plus inorganic phosphate) ratio were lower in patients with heart failure at maximal load. Blood flow was less at maximal exercise in patients with heart failure than in control subjects in keeping with the reduced work load. 5. The phosphocreatine depletion induced in the gastrocnemius muscle by exercise was more severe than previously described in the forearm of patients with heart failure. 6. Metabolic abnormalities in skeletal muscle may contribute to exercise intolerance in heart failure, particularly during submaximal exercise

Mutation Spectrum in TPO Gene of Bangladeshi Patients with Thyroid Dyshormonogenesis and Analysis of the Effects of Different Mutations on the Structural Features and Functions of TPO Protein through In Silico Approach

Although thyroid dyshormonogenesis (TDH) accounts for 10-20% of congenital hypothyroidism (CH), the molecular etiology of TDH is unknown in Bangladesh. Thyroid peroxidase (TPO) is most frequently associated with TDH and the present study investigated the spectrum of TPO mutations in Bangladeshi patients and analyzed the effects of mutations on TPO protein structure through in silico approach. Sequencing-based analysis of TPO gene revealed four mutations in 36 diagnosed patients with TDH including three nonsynonymous mutations, namely, p.Ala373Ser, p.Ser398Thr, and p.Thr725Pro, and one synonymous mutation p.Pro715Pro. Homology modelling-based analysis of predicted structures of MPO-like domain (TPO142-738) and the full-length TPO protein (TPO1-933) revealed differences between mutant and wild type structures. Molecular docking studies were performed between predicted structures and heme. TPO1-933 predicted structure showed more reliable results in terms of interactions with the heme prosthetic group as the binding energies were -11.5 kcal/mol, -3.2 kcal/mol, -11.5 kcal/mol, and -7.9 kcal/mol for WT, p.Ala373Ser, p.Ser398Thr, and p.Thr725Pro, respectively, implying that p.Ala373Ser and p.Thr725Pro mutations were more damaging than p.Ser398Thr. However, for the TPO142-738 predicted structures, the binding energies were -11.9 kcal/mol, -10.8 kcal/mol, -2.5 kcal/mol, and -5.3 kcal/mol for the wild type protein, mutant proteins with p.Ala373Ser, p.Ser398Thr, and p.Thr725Pro substitutions, respectively. However, when the interactions between the crucial residues including residues His239, Arg396, Glu399, and His494 of TPO protein and heme were taken into consideration using both TPO1-933 and TPO142-738 predicted structures, it appeared that p.Ala373Ser and p.Thr725Pro could affect the interactions more severely than the p.Ser398Thr. Validation of the molecular docking results was performed by computer simulation in terms of quantum mechanics/molecular mechanics (QM/MM) and molecular dynamics (MD) simulation. In conclusion, the substitutions mutations, namely, p.Ala373Ser, p.Ser398Thr, and p.Thr725Pro, had been involved in Bangladeshi patients with TDH and molecular docking-based study revealed that these mutations had damaging effect on the TPO protein activity