Application Of One-stop Triple Rule-out With320-slice Volume Computed Tomography In The Diagnosis Of Acute Chest Pain

ObjectiveExplored the feasibility and image quality of320-slice volume computedtomography (CT) one-stop chest pain angiography for the evaluation of patientswith noncritical, acute chest pain, pulmonary artery, thoracic aorta and coronaryartery disease.Materials and methodsForty eight consecutive patients (31male,17female, age range35-75years,mean age59years, weight range45-92kg) with noncritical, acutechest pain underwent one-stop angiography applying320-slice CT volumemodel of triple scanning sequence of chest pain combined with ECG gatingtechnology. Contrast medium was administered using a dual-head power injectorand a triphasic injection protocol, and the contrast material with an iodinecontent was administered intravenously. Data acquisition was automaticallytriggered, continuously acquiring chest cardiac continuous volume data andupper chest volume data in one check. After two-step image processing, we gotthe coronary CTA images and whole chest images,pulmonary artery images andthoracic aorta images. We used maximum intensity project(MIP),curved planarreconstruction (CPR), volume rendering (VR) multi-planar reconstruction(MPR)and other techniques to reconstruct images. Image quality scored on a four-pointscale by two experienced radiologists.ResultsVessel attenuation values of different vascular territories were recorded,included thoracic aorta, pulmonary artery and coronary artery. Mean attenuationwas436±62HU in the ascending aorta,334±52HU in the aortic arch,455±71HU in the descending aorta,492±94HU in the pulmonary trunk, and416±63HU and426±61HU in the right and left coronary artery, respectively.The following lesions were detected: acute pulmonary embolism (n=9),chronic pulmonary embolism with right ventricular failure (n=2), atheroscleroticplaque rupture at the aortic arch (n=7), pulmonary consolidation (n=3), pleuraleffusion (n=2), pericardial effusion (n=1), non-critical stenosis (less than50%lumen narrowing) of the RCA (n=6), noncritical stenosis of the LAD (n=11),complex anatomic anomaly (n=1).Based on the dose-length product, effective dose was estimated rangedbetween7and11mSv, for the chest examination using250mA,120kV, and0.35s rotation time. The total radiation exposure of the cardiac examination wascalculated to range between3mSv and5mSv in patients in whom data wereacquired during a single heartbeat and9mSv in the patient in whom a seconddata acquisition was initiated at the next heartbeat.In this study, total amount (ranged between80and90ml) of iodinatedcontrast media was less than the previous studies, which was basically the sameas the total amount in the dual source CT in the diagnosis of acute chest pain. Inthis way， we can not only ensure the diagnostic quality of images, but alsoreducing the iodine contrast agent amount.ConclusionsThis study achieved an excellent diagnostic quality for patients withnoncritical, acute chest pain, and provided a good image quality to identify thespecific cause of acute chest pain, at the same time played an important role inthe diagnosis of unexplained chest pain. This result was achieved with lesscontrast material and reduced radiation exposure compared with previouslyinvestigated imaging protocols and reduced the hazards of a large radiation doseand the more volume of contrast agent. It can substantially reduced the motionartifacts of the thoracic vascular，and can also be detected in the other chest painetiology， so it has very practical significance.