Giant Pseudoaneurysmof Ascending Aorta complicating Recurrent Mediastinitis after Cardiac Surgery / 대한흉부외과학회지

A 30 years old female patient was diagnosed valvular heart disease and double valve replacement was ndertaken. After operation, mediastinitis developed and we had done continuous mediastinal irrigation and had used IV antibiotics for 3 weeks. During outpatient follow-up, infection signs developed, so she readmitted and was reoperated because CT revealed mediastinal abscess. No infected material was observed at the operation. Infection signs continued for 3 weeks. Chest CT revealed giant pseudoaneurysm of ascending aorta. We resected the pseudoaneurysm and performed an aortoplasty with bovine pericardium under deep hypothermia and total circulatroy arrest. She recovered well and was discharged without any complication.

Acute Myocardial Infarction after a Bee Sting

Acute myocardial infarction after a bee sting is a very rare process. Among proposed mechanisms, vasospasm of the coronary artery is the most probable mechanism. Many mediators are included in the venom of wasps, and those mediators have vasoconstrictive properties and may constrict the coronary artery. Furthemore, those mediators have thrombogenic properties that lead to thrombogenesis in the coronary artery and aggravate myocardial ischemia. Epinephrine, commonly used in the management of anaphylactic shock, may further aggravate myocardial ischemia. We experienced two cases of acute myocardial infarction after a bee sting. In the first case, we could find no underlying abnormalities of the coronary vessel because the patient died during coronary angiography. In the second case, the electrocardiogram showed inferior wall myocardial infarction, but only mild stenosis of the right coronary artery was seen in coronary angiography.

First-pass Perfusion Disturbance of Coronary Artery Stenosis: An Experimental Study Using MR Imaging with Gd-DTPA Enhancement

PURPOSE: In order to determine the value of first-pass MR imaging in the diagnosis of myocardial ischemia, first-pass perfusion abnormality of coronary artery stenosis was observed in MRI after gadopentate dimeglumine (Gd-DTPA) enhancement. MATERIALS AND METHODS: The left anterior descending (LAD) coronary arteries of six dogs were subjected to approximately 70% stenosis confirmed by coronary angiography. Half an hour after adenosine and 99mTc-sestamibi infusion, Gd-DTPA (0.2 mmol/kg) and methylene blue were administered and termination was induced with potassium chloride. SE T1-weighted and single-photon emission computed tomography (SPECT) images were subsequently obtained and the findings of perfusion defect compared with specimen stain. Three dimensionally reconstructed MR images were used to measure signal intensity (SI) of normal myocardium and perfusion defect from their sectional and total volume. RESULTS: Five of six dogs with LAD artey stenosis ranging from 66% to 73% displayed perfusion defect on MRI, SPECT, and specimen stain, but the remaining dog with stenosis of 58% showed no such defect. MRI showed the perfusion defect as distinct low SI, enabling the measurement of percentage perfusion defect (24.4+/-5.4%), which increased inferiorly. SI of normal myocardium and perfusion defect decreased inferiorly; their difference indicated stenosis-induced perfusion loss according to section location. Volumetric SI of normal myocardium and perfusion defect were 3.42+/-0.52 and 2.16+/-0.45, respectively (p < 0.05). CONCLUSION: Gd-DTPA enhanced MRI displayed first-pass perfusion abnormality of coronary artery stenosis as perfusion defect with distinct low SI ; this enabled the measurement of its volume and SI changes according to section location, and thus indicated the value of first-pass MR imaging in the diagnosis of myocardial ischemia.