Đang chuẩn bị liên kết để tải về tài liệu:
Cardiology Core Curriculum - part 8

Không đóng trình duyệt đến khi xuất hiện nút TẢI XUỐNG Tải xuống

Câu trả lời cho câu hỏi 2 hình 13,12 cho thấy một chụp mạch cộng hưởng từ của khoang ngực. Trong chụp mạch này, nhanh chóng lưu lượng máu được ghi nhận là bóng nhẹ hơn trong khi dòng chảy chậm hơn được chỉ định trong tông màu tối hơn. Trái tim là trước trong bức ảnh này | Cardiology Core Curriculum Answer to question 2 Figure 13.12 shows a magnetic resonance angiogram of the thoracic cavity. In this angiogram rapid blood flow is recorded as lighter shading while slower flow is indicated in darker tones. The heart is anterior in this photo blurred due to motion artifact and the descending aorta is located posteriorly. Within the aorta a partition is visualized which is the intimal flap of the dissection. On one side of the flap normal blood flow is present and is the lighter of the two zones. This represents the true lumen of the aorta. The false lumen is the channel created by the dissection process within the media of the aorta and is the darker of the two zones. This patient subsequently underwent contrast aortography Figure 13.13 . The thoracic angiogram shows the catheter in the true aortic lumen. In this study the entire length of the dissection is visualized from its origin just above the aortic valve to its distal aspect within the descending aorta. Also note the opacification of the left ventricle which indicates aortic regurgitation through an incompetent aortic valve. These studies show this to be a proximal type A dissection with involvement of the ascending aorta as well as the arch and descending aorta. Answer to question 3 The ideal study would be one that is readily available quickly performed sensitive for the diagnosis of dissection anywhere along the aorta able to identify the site of intimal disruption which determines the surgical approach and can identify concomitant aortic regurgitation or pericardial effusion. Historically the gold standard for the diagnosis of aortic dissection has therefore been invasive catheterization and angiography. However the newer non-invasive modalities are highly sensitive and often eliminate the need for angiography. These include magnetic resonance imaging transesophageal echocardiography and computed tomography. Although the positive and negative predictive values favor magnetic