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Stress echocardiography (SE) is a recently developed technique to detect coronary artery disease and myocardial ischemia, and in increasing importance because several advantages are offered over nuclear perfusion imaging. Particularly, it is well established in acute coronary syndrome, that impaired left ventricular function is not always an irreversible process, and the information obtained using SE is useful for evaluating myocardial viability. Additionally, a progress in computer technology permits us to quantitatively assess the regional myocardial function during ischemia induced. Then, we introduced the feasibility of the pharmacological and exercise stress echocardiography for detecting myocardial ischemia and viability in this report.

Guanylin and uroguanylin are novel peptides that are first isolated from rat jejunum and opossum urine, respectively. They bind to and activate guanylyl cyclase-C (GC-C) to regulate intestinal and renal fluid and electrolyte transport through the second messenger, cyclic GMP. Heat-stable enterotoxins produced by pathogenic bacteria have close structural similarities to guanylin and uroguanylin, and they use this mimicry to act on GC-C, causing life-threatening secretory diarrhea. Guanylin primarily is restricted to the intestine, whereas uroguanylin is present in the stomach kidney, lung and pancreas in addition to intestine. Guanylin and uroguanylin in the intestine are secreted into the lumen and blood in response to sodium chloride administration. These peptides will function in salt and water transport in the intestine and kidney by luminocrine and/or endocrine actions. Guanylin peptide family links the intestine with the kidney and could play the physiological roles in the control of water and electrolyte balance.

Arrhythmias with ventricular rate between 60-100/min are discussed. Premature ventricular complex is considered to be a risk factor for sudden cardiac death and sustained ventricular tachycardia under some particular conditions, especially after myocardial infarction. To improve the prognosis of patients with ventricular arrhythmias, many trial were performed. Ventricular arrhythmia hypothesis was based on the thought that the patients' prognosis would be improved by suppression of ventricular arrhythmias with antiarrhythmic agents. However, CAST study showed unexpected results. Recently, some investigators suggest that antiectopic action and antifibrillatory action are different and empiric therapy with amiodarone is reported. Other arrhythmias with normal heart rate are considered to have little risk for survival. Then antiarrhythmic therapy should be based on quality of life.

Atherosclerotic true aortic aneurysms develop in the abdominal aorta more commonly than in any other arteries. Once developed, the natural course of true aortic aneurysm is one of progressive growth until it ruptures. The growth rate of true aortic aneurysms is variable, but the average is approximately 1.5 mm in diameter in the thoracic, and 4 mm in the abdominal aorta per year. The symptoms of aneurysms are variable. Many true aneurysms are asymptomatic, but usually the onset of chest or back pain develop in aortic dissection. Medical imagings, such as ultrasound and CT scan, are the most useful diagnostic methods for aortic aneurysms. And preoperatively, atherosclerotic lesions in the other arteries, such as coronary artery or cerebral artery, that cause perioperative death or late complications must be studied.