부산대학교 도서관

Coarctation of the aorta is a defect in the arch of the main systemic artery whereby it becomes occluded (blocked). This problem can be repaired surgically, allowing resumption of normal blood pressure and blood flow. Often, the vessels will become blocked again (recoarctation), but resting blood pressure readings will remain normal. Blood pressure readings during exercise will usually be abnormal, however, indicating that the vessel has become obstructed. Further examination is then required, usually by invasive methods, to confirm the new blockage. Doppler echocardiography is a noninvasive technique for measuring blood flow in the heart. It uses high frequency sound waves (ultrasound) to produce images of flow through the heart. It has been suggested that this technique could replace invasive techniques to confirm recoarctation of the aorta. This study examined flow in patients with suspected recoarctation using echocardiography and comparing the results with those of invasive methods. Pressure gradients (differences in aortic pressure during the heart beat) were measured in 16 patients by both invasive and noninvasive techniques. Results showed that Doppler estimated peak instantaneous gradient measurements and peak-to-peak gradient measurements at rest and during exercise were in good agreement with measurements by invasive means. The results suggest that Doppler echocardiography is a quick and easy means to measure blood flow gradients in patients who may have recurrence of aortic coarctation. (Consumer Summary produced by Reliance Medical Information, Inc.)