Study on the relationship between Cardio-cerebrovascular events and the level of Atherosclerosis evaluated by Heart-brain Integrated CTA

Objective: To establish a one-stop cardio-cerebral vascular scanning technique based on double-source helical CT by analyzing the relationship between the nature of coronary artery, extracranial and extracranial vascular plaque, the degree of lumen stenosis and the occurrence and development of cardio-cerebrovascular disease (CCVD). Methods: the plaque properties, vascular stenosis degree, and plaque quantitative analysis results of coronary artery, extracranial and intracranial segments of coronary artery, extracranial and intracranial carotid artery in 39 patients who underwent combined heart-brain CTA scanning were analyzed. The correlation between the load degree of cardio-cerebrovascular plaque and cardio-cerebrovascular events was analyzed comprehensively. Results: there were significant differences in age, high-density lipoprotein, diabetes, hypertension, smoking, plaque nature, plaque location, plaque composition and NIHSS score between the two groups. Conclusion: the combination of heart and brain CTA can help to establish the best clinical predictive model to prevent and stop the occurrence and development of coronary heart disease and stroke in time.

the main cause of death and disability of adults in China. We believe that lumen stenosis, plaque shedding, and intra-plaque hemorrhage caused by carotid atherosclerosis are the main causes of stroke 3 . Some experiments have proved that there is a close relationship between carotid atherosclerosis and coronary artery atherosclerosis 4 . Nowadays, the concept of prevention has gradually taken root in the hearts of the people, and the main battlefield of cardio-cerebrovascular diseases has been gradually transformed into primary prevention 5 . The purpose of this study is to establish a one-stop cardio-cerebral macrovascular scanning process based on dual-source spiral CT and to establish a standard for evaluating plaque load. To establish a risk model of cardiovascular and cerebrovascular recurrence of extracranial and extracranial large artery stenosis based on whole-body plaque load measurement. Timely prevent and stop the occurrence and development of coronary heart disease and stroke.
The age was 42mi 83 years old, with an average of 65.6 ±12.5 years old. According to the occurrence of cardio-cerebrovascular events, patients were divided into two groups: patients with cardio-cerebrovascular events and those without cardio-cerebrovascular events.

2.3Cox regression analysis
Univariate analysis showed that there were significant differences in age, high-density lipoprotein, diabetes, hypertension, smoking, plaque nature, plaque location, plaque composition, and NIHSS score between cardio-cerebrovascular event group and noncardio-cerebrovascular event group. (Table 2) Model 1 a included the presence of CCVD as entering variables, whereas Model 2 a used the extent of CCVD.

quantitative analysis of plaques
All patients' images were measured and quantitatively analyzed by the modified APQ (AUTOPLAQ) technique (figure 1). The results of plaque quantitative analysis (Table 3) were compared in patients with the symptomatic cardio-cerebrovascular disease ((CCVD)).
Based on the evaluation of systemic atherosclerosis, the risk stratification index of cardiovascular events in symptomatic CCVD patients was established.

Discussion
The nature of atherosclerotic plaque and lumen stenosis are significantly related to the occurrence of cardio-cerebrovascular events 6 . Therefore, by detecting and judging the degree of atherosclerosis, especially the stability of plaque, and combining with clinical NIHISS score and cardio-cerebrovascular risk factors, it is of great significance for clinical guidelines to prevent the occurrence of cardio-cerebrovascular events.
In the process of clinical diagnosis, a one-stop CTA can well reflect the degree of atherosclerosis 7 . And one-stop CTA has the advantages of short scanning time, low radiation dose, and good safety, which makes it an inspection method with broad application prospects 8 . The improved APQ technique can more accurately analyze the noncalcified components in the plaque so that the plaque parameters can be obtained more accurately, which is helpful to comprehensively evaluate the plaque load of the coronary artery and head-carotid artery. The commonly used clinical calcification score CACS refers to Agatston score 9 , its disadvantage is due to the partial volume effect, the small calcification plaque score is easy to change during reexamination, the improved APQ technique avoids this change. Keelan 10  Some experiments have proved that carotid artery disease has a high predictive value for coronary artery disease 12 . Considering the characteristics of ultrasonic detection of carotid artery, such as non-invasive, convenient, repeatable and relatively cheap, when planning to use heart-brain integrated CTA to evaluate coronary artery and carotid artery disease, it is reasonable to exclude traditional risk factors for ultrasonic detection of carotid artery in advance, and it is not recommended or recommended to apply heartbrain integrated CTA to the physical examination of people without indications. In patients with multiple hard plaques or mixed plaques in the carotid artery, the examination of integrated heart-brain CTA may be more targeted 13 .
Our study found that the more risk factors of cardiovascular and cerebrovascular diseases such as male, older, smoking, hypertension, diabetes, hyperlipidemia, the greater the probability of cardiovascular and cerebrovascular events, the more likely it is to induce cardio-cerebrovascular events.
There are still many shortcomings in this study, such as limited sample size, the low exposure level of cardio-cerebrovascular diseases, lack of long-term follow-up, and followup comparison of imaging and clinical data.
In summary, this study used integrated heart-brain CTA scan to establish a risk prediction model for patients with symptomatic intracranial and extracranial stenosis based on whole-body plaque load score, so as to realize individualized treatment of intracranial arterial stenosis, optimize the allocation of medical resources, optimize the process of stroke prevention and treatment, improve medical efficiency and reduce stroke incidence and recurrence rate, which is of great significance to the secondary prevention of stroke.

Conclusion
We found that NCPVolume,TotalPlaqueBurden (%), RemodelingIndex) is the risk factor of cardio-cerebrovascular events, among which TotalPlaqueBurden has the greatest risk. The combination of the three can be widely used in clinical practice to predict cardiocerebrovascular events.

Object
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 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.

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.

Image reconstruction and data post-processing
The collected data were processed by ADW4. 6  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 stenosis 14 , 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.

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 x 2 , Cox regression method to analyze the correlation between various factors and cardio-cerebrovascular diseases.
Declarations approved the final manuscript.

Funding
The project was supported by the Hospital level project of Beijing Liangxiang Hospital number2018-02.

Availability of data and materials
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Ethics approval and consent to participate
The research plan has been submitted to the ethics committee of Liangxiang Hospital,

Consent for publication
Not applicable.