Ischemic dysfunction

Gerber BL, Vanoverschelde JL, Bol A, Michel C, Labar D, Wijns W et al. Myocardial blood flow, glucose uptake, and recruitment of inotropic reserve in chronic left ventricular ischemic dysfunction. Imphcations for the pathophysiology of chronic myocardial hibernation. Circulation 1996 94 651-659... 

C. Depre, J.L. Vanoverschelde, J.A. Melin, M. Borgers, A. Bol, J. Ausma, R. Dion and W. Wijns, Structural and metabolic correlates of the reversibility of chronic left ventricular ischemic dysfunction in humans, Am J Physiol 268, H1265-1275 (1995). 

Cardiac anaphylaxis is an acute ischemic dysfunction comprising coronary vasoconstriction and arrthythmias. The heart is repleat with interstitial mast cells... 

Meyer S, Strittmatter M, Fischer C, Georg T, Schmitz B. Lateralization in autonomic dysfunction in ischemic stroke involving the insular cortex. Neuroreport 2004 15(2) 357-361. 

To control risk factors and prevent major adverse cardiac events, statin therapy should be considered in all patients with ischemic heart disease, particularly in those with elevated low-density lipoprotein cholesterol. In the absence of contraindications, angiotensin-converting enzyme inhibitors should be considered in ischemic heart disease patients who also have diabetes melli-tus, left ventricular dysfunction, history of myocardial infarction, or any combination of these. Angiotensin receptor blockers... 

Ventricular premature depolarizations occur with variable frequency, depending on underlying comorbid conditions. The prevalence of complex or frequent VPDs is approximately 33% and 12% in men with and without CAD, respectively 34 in women, the prevalence of complex or frequent VPDs is 26% and 12% in those with and without CAD, respectively.35 Ventricular premature depolarizations occur more commonly in patients with ischemic heart disease, a history of myocardial infarction, and HF due to LV dysfunction. They may also occur as a result of hypoxia, anemia, and following cardiac surgery. 

With either type of dialysis, studies suggest that recovery of renal function is decreased in ARF patients who undergo dialysis compared with those not requiring dialysis. Decreased recovery of renal function may be due to hemodialysis-induced hypotension causing additional ischemic injury to the kidney. Also, exposure of a patient s blood to bioincompatible dialysis membranes (cuprophane or cellulose acetate) results in complement and leukocyte activation which can lead to neutrophil infiltration into the kidney and release of vasoconstrictive substances that can prolong renal dysfunction.26 Synthetic membranes composed of substances such as polysulfone, polyacrylonitrile, and polymethylmethacrylate are considered to be more biocompatible and would be less likely to activate complement. Synthetic membranes are generally more expensive than cellulose-based membranes. Several recent meta-analyses found no difference in mortality between biocompatible and bioincompatible membranes. Whether biocompatible membranes lead to better patient outcomes continues to be debated. 

VF is electrical anarchy of the ventricle resulting in no cardiac output and cardiovascular collapse. Sudden cardiac death occurs most commonly in patients with ischemic heart disease and primary myocardial disease associated with LV dysfunction. VF associated with acute MI may be classified as either (1) primary (an uncomplicated MI not associated with heart failure [HF]) or (2) secondary or complicated (an MI complicated by HF). 

Goal BP values are <140/90 for most patients, but <130/80 for patients with diabetes mellitus, significant chronic kidney disease, known coronary artery disease (myocardial infarction [MI], angina), noncoronary atherosclerotic vascular disease (ischemic stroke, transient ischemic attack, peripheral arterial disease [PAD], abdominal aortic aneurysm), or a 10% or greater Framingham 10-year risk of fatal coronary heart disease or nonfatal MI. Patients with LV dysfunction have a BP goal of <120/80 mm Hg. 

Bcl-2 B cell lymphoma protein 2 (Bcl-2) is a family of proteins that regulate apoptosis (programmed cell death). Apoptosis is a necessary process whereby aged or damaged cells are replaced by new cells. Dysfunction of the apoptosis process results in disease inhibition of apoptosis results in cancer, autoimmune disorder, and viral infection, whereas increased apoptosis gives rise to neurodegenerative disorders, myelodysplastic syndromes, ischemic injury, and toxin-induced liver disease. 

Myocardial ischemia and infarction cause abnorma myocardial metabolism, decreased left ventricular (LV) systolic function, diastolic dysfunction, congestive heart failure, and decreased survival. Consequently, revascularization techniques, either surgical or catheter based, have become integral to treatment of severe ischemic heart disease. 

For patients with chronic CAD, nuclear imaging is essential for addressing the following major clinical issues (i) detection of ischemic myocardium, (ii) differentiation between viable hibernating or stunned myocardium and scar tissue in mechanically dysfunctional regions, and (ill) risk stratification for future major adverse events. Such information provides the basis for percutaneous coronary intervention (PCI) or coronary artery bypass (CAB) surgery and assessing their outcomes based on detection of residual ischemia and recovery of contractile function. 

Size and severity of ischemic areas correlate well with mortality in both stable CAD populations [70] and after myocardial infarction [71]. Moreover, the presence of ischemia in a dysfunctional segment of myocardium is a powerful predictor of functional recovery. Up to 83% of regions with reversible defects (ischemia) will improve with revascularization compared to only 33% for regions where no reversibility was demonstrated [72]. In patients with heart failure, viable poorly contracting myocardium correlates with recovery... 

Sawada S, Hanoi O, Barclay J, Geiger S, Fain R, Foltz J et al. Usefulness of positron emission tomography in predicting long-term outcome in patients with diabetes mellitus and ischemic left ventricular dysfunction. Am J Cardiol 2005 96 2-8... 

Abstract Two thirds of the nearly half a million deaths per year in the United States due to sudden cardiac death (SCD) is attributed to coronary artery disease (CAD) and most commonly results from untreated ventricular tachyarrhythmias. Patients with ischemic cardiomyopathy and left ventricular dysfunction are at highest risk for SCD, but this still defines only a small subset of patients who will suffer SCD. Multiple lines of evidence now support the superiority of implantable cardioverter defibrillator (ICD) therapy over antiarrhythmic therapy for both primary and secondary prevention of SCD in advanced ischemic heart disease. Optimization of ICD therapy in advanced ischemic cardiomyopathy includes preventing right ventricular pacing as well as the use of highly effective anti-tachycardia pacing to reduce the number of shocks. While expensive, ICD therapy has been shown to compare favorably to the accepted standard of hemodialysis in cost effectiveness analyses. 

Veenhuyzen GD, Sing SN, McAreavey D, et al. Prior coronary artery bypass surgery and risk of death among patients with ischemic left ventricular dysfunction. Circulation 2001 104 1489-1493. 

Clinical trials of skeletal myoblasts have focused on the treatment of patients with ischemic cardiomyopathy and systolic dysfunction. Overall, these trials have resulted in improved segmental contractility and global LVEF. The preferred delivery route has been surgical intramyocardial injection, and one feasibility trial of transendocardial injection has been reported in the literature so far. 

Corr PB, Gross RW, Sobel BE Amphipathic metabolites and membrane dysfunction in ischemic myocardium. Cite Res 1984 55 136-142. 

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