A total of 39 patients with suspected coronary heart disease or stroke who were admitted to our hospital in 2018.06 /2019.05 were examined by combined heart-brain CTA, and all patients were treated with standardized and optimized drug therapy. All patients were followed up at 3 and 6 months after onset, and the medication, vital signs, and cardiovascular and cerebrovascular events (ischemic stroke, coronary syndrome, vascular death) were recorded. All patients completed relevant laboratory tests within 24 hours of admission, such as blood glucose, HbA1C, D-dimer, four items of blood coagulation, LDL-C, HDL-C, TG, TCH, biochemical markers (CRP, hs-CRP, MMP2, MMP9, oxLDL-C, etc.). The inclusion criteria were: (1) age: 18 Mel 80 years old; (2) auxiliary examination (including carotid ultrasound TCD, head, and neck CTA or MRA) indicating intracranial artery stenosis; (3) patients with clinical symptoms suspected of coronary heart disease; (4) ≥ two atherosclerotic risk factors (5) informed consent of patients and their families. The exclusion criteria were as follows: (1) patients with irregular heart rate could not complete combined heart and brain CTA examination (2) patients with PF0, atrial fibrillation, connective tissue disease, tumor and other non-atherosclerotic stroke, (3) head CT or MRI indicated hemorrhage, watershed infarction, or other diseases (vascular malformation, tumor, brain abscess, etc.); (4) patients with previous history of gastrointestinal ulcer who could not tolerate dual anti-platelet aggregation therapy with aspirin and clopidogrel, (5) patients with decreased liver and renal function (ALT, AST ≥ 3 times normal high limit or creatinine F > 1.5mg/dl) or increased CK (≥ 10 times normal high limit); (6) allergic to aspirin, clopidogrel and statins, or could not be tolerated.
5.2 Inspection method
Siemens dual-source CT was used for large pitch scanning, the scanning range was from the other side to the top of the head, and the direction of the foot was scanned. FlashSpira mode is adopted. Pitch: 3.2, tube voltage 70mur90kV, tube current 330Mur450mAs, rotating speed 0.25s/ circle, collimation width: 0.6mm*96. Contrast agent iohexol 50ml was injected intravenously with 5ml/s, followed by saline 50ml at the same rate. The aortic root was selected to set the threshold for ROI, to 100HU, and the contrast tracer technique (Bolus-tracking method) was used to detect the density change of RIO. When the CT value of the RIO exceeded the threshold, the scan was triggered automatically with a delay of 8 seconds. The heart scan ECG triggers 30% or 65% of the cardiac cycle.
5.3 Image reconstruction and data post-processing
The collected data were processed by ADW4.6 workstation for various post-processing images, including volume rendering (VR), maximum density projection (MIP), curved surface reconstruction (CPR) reconstruction layer thickness of 0.75mm and spacing of 0.4mm. The best quality CTA images were analyzed for analysis and diagnosis. At the same time, the plaques of blood vessels were measured and quantitatively analyzed by the modified APQ (AUTOPLAQ) technique in all patients' images. The branch of the coronary artery is divided into three parts: the left trunk and left anterior descending branch, left circumflex branch, and the right coronary artery. The head and carotid artery is divided into four parts: the extracranial segment of the right head-carotid artery, the extracranial segment of the left head-carotid artery, the intracranial segment of the right head-carotid artery, and the extracranial segment of the left head-carotid artery, including the aortic arch, the subclavian artery, the common carotid artery, the extracranial segment of the internal carotid artery and the extracranial segment of the vertebral artery. The intracranial segment of the cephalic carotid artery includes basilar artery, bilateral internal carotid artery, vertebral artery and anterior, middle and posterior cerebral arteries. For vessels with stenosis, the vessel diameter is measured by APQ vascular analysis software, and then according to the degree of stenosis, it can be divided into severe stenosis group (stenosis rate > 75%), moderate stenosis group (stenosis rate 50%-74%), mild stenosis group (stenosis rate < 50%). Vascular stenosis ≥ 50% was defined as meaningful stenosis, and the degree of vascular stenosis was calculated. The degree of stenosis = (1 the lumen area of the lesion site / the lumen area of the control site) x100%. It is found that the risk of plaque composition and its stability for atherosclerosis is much higher than that of arterial lumen stenosis14, so we further analyze the composition of plaque. Using the improved APQ non-calcified plaque detection technique, the plaque was divided into calcified plaque, non-calcified plaque and mixed plaque. We define non-calcified plaques and mixed plaques as unstable plaques. The indexes of non-calcified plaques were evaluated comprehensively.
5.4 Statistical analysis
SPSS statistical software was used to integrate and process the data. The measurement data were expressed as "x ±s," the t-test of independent samples was adopted, and the counting data were analyzed by x2 ,Cox regression method to analyze the correlation between various factors and cardio-cerebrovascular diseases.