0D-1D coupling model and 3D fluid-structure interaction model based on coronary CT angiography for displaying hemodynamic characteristics of coronary artery stenosis

Objective To observe value of 0D-1D coupling model and 3D fluid-structure interaction(FSI)model based on coronary CT angiography(CCTA)for displaying hemodynamic characteristics of coronary artery stenosis.Methods Based on CCTA data of the stenosed left anterior descending branch(LAD)in a patient with coronary heart disease,an 0D-1D coupling model and 3D FSI model were built,respectively.Then hemodynamic characteristic indexes,including the pressure,flow velocity and wall shear stress(WSS)were obtained in every 0.01 s during 1 s at 5 sampling points(i.e.sampling point 1—5)using these 2 models,respectively,and the consistencies of the results between models were evaluated with Spearman correlation coefficient r s.Results The time consuming for construction of 0D-1D coupling model and 3D FSI model was 0.033 min and 704 min,respectively.Both models showed basically distribution of the pressure,flow velocity and WSS of the stenosed LAD.For more details,the pressure at the stenosed segment of LAD and the proximal segment of stenosis were both higher,which gradually decreased at the distal segment of stenosis,and the flow velocity at the proximal segment of stenosis was in a relatively slow and uniform condition,with significantly increased flow velocity and WSS at the stenosed segment.Compared with 3D FSI model,0D-1D vascular coupling model was relatively unrefined and lack of distal flow lines when displaying blood flow velocity.For sampling point 2 at the stenosed segment of LAD,no significant consistency for pressure between 2 models was found(P=0.118),but strong consistency for the flow velocity and WSS(r s=0.730,0.807,both P<0.05).The consistencies of pressure,flow velocity and WSS between 2 models at the proximal and distal segment of stenosis,i.e.1,3—5 sampling points were week to moderate(r s=0.237—0.669,all P<0.05).Conclusion 0D-1D coupling model exhibited outstanding computational efficiency and might provide relatively reasonable results,while 3D FSI model showed higher accuracy for details and streamline when simulating LAD stenosis.

High Prevalence of Anatomical Variations and Anomalies of the Coronary Arteries Detected by CT Angiography in Symptomatic Patients

Objective:Coronary artery anatomical variations and anomalies are an important topic due to their potential clinical manifestations.This study aims to investigate the prevalence of coronary artery anatomical variations and anomalies in symptomatic patients with coronary computed tomography angiography(CCTA).Methods:This is a retrospective study that included all symptomatic patients who had CCTA in a tertiary care hospital in Saudi Arabia during a period of seven years.Results:The total number of included patients was 507(60%males)with a mean age of 57.4 years.Approximately 41%had luminal stenoses,averaging 49.7%.The total num-ber of patients with coronary anatomical variations(CAV)and coronary artery anomalies(CAA)was 217(43%).CAV prevalence was 26%,which included 14%non-right coronary dominance,5%short left main coronary artery(LMCA),and 7%division variations(trifurcation and quadrifurcarion)of the LMCA.The prevalence of CAA was 29%,which included 5%origin anomalies,22%myocardial bridge,and 2%course anomalies.Conclusions:A high prevalence of coronary artery anatomic variations and anomalies in symptomatic patients is reported in this study.Systematic reviews,meta-analyses,reporting guidelines,and unified definitions and classifications of cor-onary variations and anomalies are lacking in the literature,presenting potential opportunities for future research and publications.

Epidemiological, Clinical and Coronary Angiography Aspects of Acute Coronary Syndrome in the Cardiology Department of the Hospital Mother-Child “Le Luxembourg”Mali

Introduction: Cardiac catheterisation plays a fundamental role in the management of acute coronary syndrome. These explorations require heavy, complex and costly equipment and a large team of doctors, nurses and technicians with highly specialized training. Aims: To describe epidemiological, clinical and coronary angiography aspects of patients with acute coronary syndrome. Patients and Methods: Descriptive study from September 2019 to December 2023 in the Cardiology Department of the Hôpital Mère-Enfant of Bamako. Inclusion criteria were patients admitted for coronary angiography with the diagnosis of acute coronary syndrome. Results: During the study period, 1253 patients underwent coronary angiography, 596 of whom had acute coronary syndrome as an indication, representing a hospital frequency of 47%. Sex-ratio was 2.10. Mean age of patients was 58.5 ± 11.39 years. ST elevation acute coronary syndrome was the most common indication with 63.92% of cases. High blood pressure was the main cardiovascular risk factor with 58.7% of cases, and radial access approach was used in 98% of cases. Coronary angiography was pathological in 91.70% of cases (n = 548). Patients with lesions of anterior interventricular artery were 73.73% of cases. Tritruncal lesions accounted for 40.63% of cases. Conclusion: ST elevation acute coronary syndrome is the most frequent manifestation of acute coronary syndrome. Anterior interventricular artery is most often the culprit lesion for our patients.

Coronary Artery Patterns in Diabetic Patients Undergoing Diagnostic Coronary Angiography-Data from a Major Cardiac Center in Yemen

Background: Diabetes mellitus (DM) is independently associated with an increased risk of cardiovascular mortality and morbidity, including coronary artery disease (CAD). CAD is a shared burden disease and the leading cause of death in developed and developing countries. We aimed to assess the angiographic patterns of coronary arteries in patients with DM in a developing country (Yemen) as the first study. Methods: This study is a cross-sectional, prospective, observational study that includes a total of 250 patients who were admitted for elective diagnostic coronary angiography. Results: 96 (38.4%) patients were diabetics;68% were male;mean age was 57 ± 11 years. The incidence of three-vessel disease was 31.2% of patients. Considering the severity of lumen occlusion, (11.2%) of patients had non-significant lesions, (37.6%) of patients had significant lesions, and (32%) had total occlusive lesions. Lesions were of LAD in 76%, RCA in 60%, and LCX in 52% of the population. Among diabetics, two and 3-vessel diseases (33.3% vs. 20.8% & 50% vs. 19.5%, P = 0.001), left main lesion (10.4% vs. 2.6%, P = 0.012), significant stenosis (41.7% vs. 35.1%, P = 0.032), total occlusion of coronary arteries (43.8% vs. 19.5%, P = 0.032) and type C lesion (66.7% vs. 35.1%, P = 0.010) were more frequent than non-DM patients. Conclusion: The burden of significant and severe coronary lesions is more common among DM, which may be the major cause of morbidity and mortality of DM in developing countries.

Effects of Continuous Precision Nursing Model on Knowledge, Attitudes, and Practices (KAP) Behavior and Cardiac Function in Patients after Percutaneous Coronary Angiography and Stent Implantation

Objective:To explore the impact of a continuous precision nursing model on patients’Knowledge,Attitudes,and Practices(KAP)and cardiac function during the nursing process of patients undergoing percutaneous coronary angiography and stent implantation.Methods:Ninety patients who underwent percutaneous coronary angiography and stent implantation in our hospital from April 2022 to April 2023 were selected and randomly divided into the control group(45 cases),in which routine nursing support was carried out during the treatment process,and the observation group(45 cases),in which continuous precision nursing model was carried out during the treatment process.Comparisons were made between the two groups of patients on their KAP,cardiac function,and quality of life during recovery.Results:There was no difference in the left ventricular ejection fraction(LVEF),cardiac output(CO),and cardiac index(CI)levels before intervention.After the intervention,the levels of cardiac function in the observation group were higher than those of the control group(P<0.05).There was no difference in the Exercise of Self-Care Agency(ESCA)self-care ability scale scores before the intervention.After the intervention,the observation group had higher ESCA scores than the control group(P<0.05).Conclusion:Implementation of a continuous precision nursing model in the care of patients undergoing percutaneous coronary angiography and stent implantation improved the patient’s cardiac function,and KAP,and promoted recovery.

Emerging role of computed tomography coronary angiography in evaluation of children with Kawasaki disease

Coronary artery abnormalities are the most important complications in children with Kawasaki disease(KD).Two-dimensional transthoracic echocardiography currently is the standard of care for initial evaluation and follow-up of children with KD.However,it has inherent limitations with regard to evaluation of mid and distal coronary arteries and,left circumflex artery and the poor acoustic window in older children often makes evaluation difficult in this age group.Catheter angiography(CA)is invasive,has high radiation exposure and fails to demonstrate abnormalities beyond lumen.The limitations of echocardiography and CA necessitate the use of an imaging modality that overcomes these problems.In recent years advances in computed tomography technology have enabled explicit evaluation of coronary arteries along their entire course including major branches with optimal and acceptable radiation exposure in children.Computed tomography coronary angiography(CTCA)can be performed during acute as well as convalescent phases of KD.It is likely that CTCA may soon be considered the reference standard imaging modality for evaluation of coronary arteries in children with KD.

Contrast-induced ischemic colitis following coronary angiography:A case report

BACKGROUND Ischemic colitis(IC)is common,rising in incidence and associated with high mortality.Its presentation,disease behavior and severity vary widely,and there is significant heterogeneity in therapeutic strategies and prognosis.The common causes of IC include thromboembolism,hemodynamic insufficiency,iatrogenic factors and drug-induced.However,contrast-induced IC,especially isolated right colon ischemia is rarely reported.CASE SUMMARY A 52-year-old man was admitted to the hospital due to intermittent chest distress accompanied by palpitation.Coronary angiography was performed using 60 mL of the iodinated contrast agent iohexol(Omnipaque 300),and revealed moderate stenosis of the left anterior descending artery and right coronary artery.At 3 h post-procedure,he complained of epigastric pain without fever,diarrhea and vomiting.Vital signs remained normal.An iodixanol-enhanced abdominal computed tomography(CT)scan revealed thickening,edema of the ascending and right transverse colonic wall and inflammatory exudate,without thrombus in mesenteric arteries and veins.Following 4 days of treatment with antibiotic and supportive management,the patient had a quick and excellent recovery with disappearance of abdominal pain,normalization of leucocyte count and a significant decrease in C reactive protein.There was no recurrence of abdominal pain during the patient's two-year follow-up.CONCLUSION This case emphasizes that contrast-induced IC should be considered in the differential diagnosis of unexplained abdominal pain after a cardiovascular interventional procedure with the administration of contrast media.Timely imaging evaluation by CT and early diagnosis help to improve the prognosis of IC.

Effects of combining multiple dose reduction techniques on coronary computed tomography angiography

BACKGROUND Coronary computed tomography angiography(CCTA)is the preferred noninvasive examination method for coronary heart disease.However,the radiation from computed tomography has become a concern since public awareness of radiation hazards continue to increase.AIM To explore the value of multiple dose reduction techniques for CCTA.METHODS Consecutive normal and overweight patients were prospectively divided into two groups:Group A1,patients who received multiple dose reduction scans(n=82);and group A2,patients who received conventional scans(n=39).The scan parameters for group A1 were as follows:Isocentric scan,tube voltage=80 kV,and tube current control using 80%smart milliampere.The scan parameters for group A2 were as follows:Normal position,tube voltage=100 kV,and smart milliampere.RESULTS The average effective doses(EDs)for groups A1 and A2 were 1.13±0.35 and 3.36±1.30 mSv,respectively.There was a statistically significant difference in ED between the two groups(P<0.01).Furthermore,noise was significantly lower,and both signal-to-noise ratio and contrast signal-to-noise ratio were higher in group A2 when compared to group A1(P<0.01).Moreover,the subjective image quality(IQ)scores were excellent in both groups,in which there was no significant difference in subjective IQ score between the two groups(P=0.12).CONCLUSION Multiple dose reduction scan techniques can significantly decrease the ED of patients receiving CCTA examinations for clinical diagnosis.

Radiation dose analysis of computed tomography coronary angiography in Children with Kawasaki disease

BACKGROUND There is evolving role of computed tomography coronary angiography(CTCA)in non-invasive evaluation of coronary artery abnormalities in children with Kawasaki disease(KD).Despite this,there is lack of data on radiation dose in this group of children undergoing CTCA.AIM To audit the radiation dose of CTCA in children with KD.METHODS Study(December 2013-February 2018)was performed on dual source CT scanner using adaptive prospective electrocardiography-triggering.The dose length product(DLP in milligray-centimeters-mGy.cm)was recorded.Effective radiation dose(millisieverts-mSv)was calculated by applying appropriate age adjusted conversion factors as per recommendations of International Commission on Radiological Protection.Radiation dose was compared across the groups(0-1,1-5,5-10,and>10 years).RESULTS Eighty-five children(71 boys,14 girls)with KD underwent CTCA.The median age was 5 years(range,2 mo-11 years).Median DLP and effective dose was 21 mGy.cm,interquartile ranges(IQR)=15(13,28)and 0.83 mSv,IQR=0.33(0.68,1.01)respectively.Mean DLP increased significantly across the age groups.Mean effective dose in infants(0.63 mSv)was significantly lower than the other age groups(1-5 years 0.85 mSv,5-10 years 1.04 mSv,and>10 years 1.38 mSv)(P<0.05).There was no significant difference in the effective dose between the other groups of children.All the CTCA studies were of diagnostic quality.No child required a repeat examination.CONCLUSION CTCA is feasible with submillisievert radiation dose in most children with KD.Thus,CTCA has the potential to be an important adjunctive imaging modality in children with KD.

Prevalence and Predictive Factors of Severe Coronary Lesions in Algerian Patients Undergoing Coronary Angiography

Background: The severity of coronary lesions in patients with coronary artery disease (CAD) has important prognostic and therapeutic consequences. Clinical symptoms not always reflect the disease severity and this study aimed to evaluate coronary lesions in the Algerian population where these data are scarce. Methods: It was a prospective cross-sectional study conducted in consecutive patients with an age ≥20 years who underwent clinically-indicated coronary angiography in our center. The objective of the study was to determine the prevalence of severe coronary lesions assessed with the Gensini score. The predictive factors of severity were evaluated in a multivariate analysis. Results: A total of 507 patients were included (male, 79.7%;mean age, 58.8 years). Coronary angiography was prescribed most frequently for ST-segment elevation myocardial infarction (STMI) (46.9%) and non-STMI (38.1%). The prevalence of severe coronary lesions was 69.6% (95% CI 65.5 - 73.5). In multivariate analysis, the independent predictive factors of severe coronary lesions were male sex (odds ratio [OR] 2.00;p = 0.0141), diabetes (OR 1.92;p = 0.0070), left ventricular dysfunction (OR 1.81;p = 0.0059), age (OR 1.72;p = 0.0297) and no lipid-lowering treatment (OR, 0.47;p = 0.0388). Conclusions: Severe coronary lesions were present in two out three patients in this cohort of Algerian patients undergoing coronary angiography. Independent predictive factors of severe coronary lesions were male sex, diabetes, age, left ventricular dysfunction and no lipid-lowering treatment. It is important to identify these at-risk patients, as they should be explored at an asymptomatic stage before a cardiovascular event and receive prompt treatment with angioplasty or surgery.

Antiphospholipid syndrome presenting as recurrent coronary thrombosis:A case report

BACKGROUND Antiphospholipid syndrome(APS)is a chronic autoimmune disease characterized by venous or arterial thrombosis,pregnancy morbidity and a variety of other autoimmune and inflammatory complications.Here,we report a case of APS associated with multiple coronary thromboses.CASE SUMMARY The patient,a 28-year-old male,suffered from recurrent coronary thromboses over a period of 31 months.Despite undergoing interventional coronary procedures,thrombolytic therapy,and anticoagulation treatment,the condition persisted intermittently.An extensive search for underlying thrombogenic factors revealed a diagnosis of APS.Accurate adjustment of the medication regimen led to the absence of further acute coronary syndrome(ACS)episodes during the subsequent 20-month follow-up.Although the patient occasionally experiences chest tightness,no further symptoms of distress have been reported.CONCLUSION APS can manifest as ACS.Screening for rheumatologic and immunological conditions is essential when encountering patients with multiple coronary thromboses.Treatment strategy should include symptomatic relief and a targeted and aggressive approach to address the underlying pathophysiology.

Bioresorbable stent unloading during percutaneous coronary intervention:Early detection and management

In this letter,we comment on a recent case report by Sun et al in the World Journal of Cardiology.The report describes the successful management of a rare complication:The unloading or detachment of a bioresorbable stent(BRS)during percutaneous coronary intervention(PCI)in a male patient.The unloading of BRS was detected via angiography and intravascular ultrasound(IVUS)imaging of the left coronary artery and left anterior descending artery.Although this case is interesting,the authors’report lacked crucial details.Specifically,insufficient information about the type of BRS used,potential causes of BRS unloading,or whether optical coherence tomography(OCT)imaging for coronary arteries was performed before,during,or after PCI.The OCT imaging of coronary arteries before PCI can potentially prevent BRS unloading due to its higher resolution compared to IVUS.In addition,despite detecting myocardial bridging during the PCI,the authors did not provide any details regarding this variation.Here we discuss the various types of BRS,the importance of OCT in PCI,and the clinical relevance of myocardial bridging.

Percutaneous Coronary Intervention in Acute Coronary Syndromes at the Mother-Child University Hospital Luxembourg in Bamako

Introduction: Acute coronary syndromes (ACS) are a diagnostic and therapeutic emergency. Objective: Studying the feasibility, difficulties and results of coronary angioplasty in acute coronary syndromes at the Luxembourg Mother-Child University Hospital in Bamako. Patients and Methods: Cross-sectional, descriptive study with prospective recruitment over 18 months from September 2020 to February 2022. All patients aged at least 18 years old admitted for SCA and having undergone PCI during the study period were included. Result: We collected 249 patients for SCA, of whom 160 underwent angioplasty, either an angioplasty/SCA ratio of 0.64. The average age of the patients was 59.54 ± 11.62 with extremes of 32 and 92 years. The age group of 45 to 65 years was the most representative. The predominance was male, sex ratio of 2.4. The main cardiovascular risk factors were high blood pressure (58.23%) and diabetes (45.78%). Persistent ST-segment elevation on the electrocardiogram was present in 71.48%. The treatment time was more than 12 hours after the first medical contact in 95.5%. The approach was radial in 96.5% of cases. Coronarography was pathological in 91.16% of our patients. The lesions were tri-truncular in 34.13% with the anterior inter ventricular as culprit artery in 72% of cases. The majority of patients (64%) had undergone angioplasty with implantation of an active stent. Angioplasty was performed successfully in 98% and per procedural mortality was 1.87%. Only 6.45% of ACS with ST elevation benefited from primary angioplasty. Conclusion: Percutaneous coronary intervention is performed routinely in our center with satisfactory results. Difficulties exist, related to the diagnostic delay of ACS and the high cost of angioplasty.

Acute Coronary Syndrome of Young Subjects at the Luxembourg Mother-Child University Hospital in Bamako

Introduction: Acute coronary syndrome is often the first event of coronary disease of young subjects. Objective: To study sociodemographic, clinical, paraclinical, therapeutic and evolutionary aspects of acute coronary syndrome of young subjects. Patients and Methods: Descriptive cross-sectional study with prospective recruitment from October 01, 2020 to March 31, 2022. Were included all patients admitted for acute coronary syndrome whose age was less or equal to 45 years and who had undergone coronary angiography at the Mother-Child University Hospital on Luxembourg from Bamako. Results: During the study period, we collected 60 patient files out of 198. These 60 patient files met our inclusion criteria. Hospital frequency was 30.30%. Average age of patients was 40.43 ± 3.9 years. Sex ratio M/F was 5.3. Main cardiovascular risk factor was smoking tobacco (23.42%), followed by dyslipidemia (13.92%). Functional signs were dominated by angina 62% followed by dyspnea 25.3%. Persistent ST-segment elevation on electrocardiogram was present in 76.4%. Left ventricular systolic dysfunction was present in 26.5%. Time to first medical contact was more than 12 hours in 62.7% of cases. Radial approach was adopted in 94% of cases. Coronary angiography was pathological in 85% (n = 51) of cases. Lesions were single-vessel disease in 47.1% and culprit artery was anterior interventricular in 51% of cases. Dual anti-platelet aggregation was aspirin and ticagrelor in 91.8% of cases. Angioplasty was performed in all patients who had significant abnormalities at coronary angiography. In-hospital mortality was 3.9%. Conclusion: Acute coronary syndromes exist in young Africans with a male predominance. Main cardiovascular risk factor is smoking tobacco. Coronary lesions are single vessel disease in the majority of case. Most of patients meet medical team after 12 hours. Time to first medical contact is a main challenge in our country.

Correlation between Neutrophil Percentage-to-albumin Ratio and Coronary Heart Disease Complicated with Diabetes Mellitus

[Objectives]This study was conducted to explore the relationship between neutrophil percentage-to-albumin ratio(NPAR)and coronary heart disease complicated with diabetes.[Methods]A total of 603 patients with coronary heart disease who underwent coronary angiography in Pingquan County Hospital from January,2023 to December,2023 and met the inclusion criteria were included as the research object.All the patients were divided into a coronary heart disease complicated with diabetes group(CAD+T2DM group)(n=298 cases)and a control group(CAD group)(n=305 cases),according to patients medical history,heart color ultrasound and biochemical test results.The clinical data,biochemical test results and coronary artery imaging data of patients were recorded,and the Gensini score was calculated.The neutrophil percentage(NEUT%)and albumin count were determined to calculate NPAR.[Results]The NPAR value of the coronary heart disease complicated with diabetes mellitus group was(1.6±0.42),which was significantly higher than that of the control group(1.47±0.49),and the difference was statistically significant(P<0.05).The area under the ROC curve was 0.619(95%CI:0.591-0.675,P<0.05),and the prediction of coronary heart disease complicated with diabetes using NPAR showed a Youden index of 0.31,a sensitivity of 60.4%,a specificity of 40.3%,and a best cut-off score of 1.4506.[Conclusions]The neutrophil percentage-to-albumin ratio(NPAR)is closely related to coronary heart disease complicated with diabetes mellitus,and NPAR has clinical application value in the diagnosis of coronary heart disease complicated with diabetes mellitus.

Feasibility analysis of coronary angiography by transradial approach with 4F catheter

Objective:To assess the feasibility of coronary angiography by transradial approach with 4F catheter.Methods:The procedural details,picture quality,local complication were recorded for coronary by transradial approach with 4F catheter in 138 patients.Results:The success rate of angiography was 97.7%;fluoroscopy time was(5.05±3.23)minutes,total procedural time was(20.51±3.37)minutes;the incidence of dislodgement,excessive engagement of either coronary artery was 7.8%,9.4%,repectively;the angiographic scores for left anterior descending,circumflex and right coronary arteries were(2.87±0.40),(2.88±0.39),(2.90±0.35),respectively.The spasm complication occurred 4.3% in radial artery and 1.5% in coronary artery.There were no occlusion of radial artery during follow up.Conclusion:4F catheter could be the first chosen in some selecting patients for its nice maneuverability,fine images and fewer vascular complications.

Performance of dual-source CT with high pitch spiral mode for coronary stent patency compared with invasive coronary angiography

Objective To investigate the performance of dual-source computed tomography （DSCT） using high-pitch spiral fliPS） mode for coronary stents patency. Methods We conducted a prospective study on 120 patients with 260 previous stents implanted due to recurred suspicious symptoms of angina scheduled for invasive coronary angiography （ICA）, while DSCT were conducted using HPS mode. Results There was no significant impact of age, body mass index or heat rate （HR） on image quality （P 〉 0.05）, while HR variability had a slight impact on that （P 〈 0.05）. Sensitivity, specificity, positive predictive value （PPV）, negative predictive value （NPV） of DSCT in detection of in-stent restenosis （ISR） based per-patient were 92.3%, 96.7%, 88.9%, and 97.8%, respectively. And those based per-stent were 87%, 96.8%, 83.3%, and 97.7% with un-assessment stents, 97.4%, 99.5%, 97.4%, and 99.5% without un-assessment stents. There was significant differ- ence on sensitivity, specificity, PPV and NPV between diameter 〉 3.0 mm group （93.3%, 97.9%, 87.5%, and 98.9%） and diameter 〈 3.0 mm group （80%, 93.3%, 80.0%, and 93.3%） （P 〈 0.05）, and that between stent number 〉 3 group （82.3%, 77.8%, 66.7%, and 60%） with 〈 3 group （97.3%, 80%, 96.5%, and 75%）. The effective dose of DSCT （1.4 ± 0.5 mSv） is significantly less than that by invasive coronary angiography [4.0 ± 0.8 mSv （P 〈 0.01）]. Conclusion DSCT using HPS mode provides good diagnostic performance on stent patency with lower effective dose in patients with HR 〈 65 beats/rain.

Application of Low Tube Voltage, Low-concentration Contrast Agent Using a 320-row CT in Coronary CT Angiography: Evaluation of Image Quality, Radiation Dose and Iodine Intake

The effect of low voltage and low concentration contrast agent on image quality of coronary CT angiography,radiation dose and iodine intake was evaluated.A total of 121 patients with body mass index(BMI)<26 kg/m2 and heart rate(HR)<70 beats/min were randomly divided into four groups:group A(n=31,80 kVp,270 mgl/mL);group B(n=33,100 kVp,270 mgl/mL);group C(h=30,100 kVp,320 mgl/mL);group D(w=27,100 kVp,400 mgl/mL).The automatic current modulation system and the iterative algorithm for reconstruction were adopted in each group.The CT values and SD values of the aortic root(AR),subcutaneous fat,left coronary artery opening(LCA),and right coronary artery opening(RCA)were measured in all groups,the signalto-noise ratio(SNR)and contrast noise ratio(CNR)were calculated,and effective radiation dose and iodine intake were recorded.The subjective assessment for image quality was performed by two physicians using a 4-point scale.The results were compared using the one-way ANOVA and rank sum tests.The image quality of the four groups met the clinical diagnostic requirements.The CT values of AR in groups A,B,C,and D were 537.6±71.4,447.2±81.9,445.2±64.9 and 518.5±94.9 Hu,respectively,with no significant difference between group A and group D,or between group B and group C,while CT values in groups B and C were significantly lower than those in groups A and D(P<0.05).In groups A,B,C,and D,the LCA SNR values were 22.7±9.1,23.3±9.1,23.3±7.7 and 26.6±8.9,and the RCA CNR values were 26.9±9.&28.5±11.4,27.7土&8 and 32」±10.6,respectively.The AR visual scores in groups A,B,C and D were 3.8±0.2,3.9±0.3,3.9±0.3 and 4.0±0.3,respectively.There were no significant differences in SNR,CNR and visual score among the four groups(P>0.05).The radiation doses in groups A,B,C and D were 2.6±1.4,3.6±1.&4.9±3.5 and 4.9±2.8 mSv,respectively.The radiation dose in group A was significantly less than that in the rest three groups(P<0.05).The iodine intakes in groups A,B,C and D were 14.9±1.5,15.0±1.5,17.7±2.0 and 18.1±2.5 g,respectively.There was no significant difference in the intake of iodine between groups C and D,or between groups A and B,while iodine intake in groups A and B were significantly reduced as compared with that in groups C and D(P<0.05).It was concluded that for patients with low BMI and controlled HR,compared to 100 kVp tube voltage combined with multiple concentration contrast agents,80 kVp combined with 270 mgl/mL contrast agent is enough to ensure the quality of the images,and can reduce the radiation dose significantly,while reducing the amount of iodine intake notably,thus reducing the incidence of adverse reaction.

Feasibility and Diagnostic Accuracy for Assessment of Coronary Artery Stenosis of Prospectively Electrocardiogram-gated High-pitch Spiral Acquisition Mode Dual-source CT Coronary Angiography in Patients with Relatively Higher Heart Rates: in Comparison wit

Objective To prospectively investigate the diagnostic accuracy for coronary artery stenosis of prospectively electrocardiogram-triggered spiral acquisition mode (high pitch mode) dual-source computed tomography coronary angiography (CTCA) in patients with relatively higher heart rates (HR) compared with catheter coronary angiography (CCA). Methods Forty-seven consecutive patients with relatively higher HR (>65 and <100 bpm) (20 male, 27 female; age 55±10 years) who both underwent dual-source CTCA and CCA were prospectively included in this study. All patients were performed CTCA using high pitch mode setting at 20%-30% of the R-R interval for the image acquisition. All coronary segments were evaluated by two blinded and independent observers with regard to image quality on a three-point scale (1: excellent to 3: non-diagnostic) and for the presence of significant coronary stenoses (defined as diameter narrowing exceeding 50%). Considered CCA as the standard of reference, the sensitivity, specificity, positive predictive value and negative predictive value were calculated. Radiation dose values were calculated using the dose-length product. Results Image quality was rated as being score 1 in 92.4% of segments, score 2 in 6.1% of segmentsand score 3 in 1.5% of segments. The average image quality score per segment was 1.064±0.306. The HR variability of patients with image score 1, 2 and 3 were 2.29±1.06 bpm, 5.17±1.37 bpm, 8.88±1.53 bpm, respectively. The average HR variability of patients with different image scores were significantly different (F=170.402, P=0.001). The sensitivity, specificity, positive and negative predictive values were 92.6%, 97.0%, 87.6%, 98.3%, respectively, per segment and 90.0%, 95.2%, 85.3%, 96.9%, respectively, per vessel and 100%, 63.6%, 90.0%, 100%, respectively, per patient. The effective radiation dose was on average 0.86±0.16 mSv. Conclusion In patients with HR more than 65 bpm and below 100 bpm without cardiac arrhythmia, the prospectively electrocardiogram-gated high-pitch spiral acquisition mode with image acquired timing set at 20%-30% of the R-R interval provides a high diagnostic accuracy for the assessment of coronary stenoses combined with a 1.5% of non-diagnostic coronary segments and a radiation dose below 1 mSv.

CORONARY ANGIOGRAPHY WITH DUAL SOURCE COMPUTED TOMOGRAPHY:INITIAL EXPERIENCE

Objective To explore the scan technique and image quality of coronary angiography with dual source computed tomography(CT) without oral metoprolol preparation.Methods Plain and enhanced dual source CT coronary angiography without oral metoprolol preparation was prospectively performed in 600 patients.Calcium scoring with plain scan images as well as multi-planar reconstruction(MPR),maximum intensity projection(MIP),and volume rendering technique(VRT) reconstruction with enhanced scan images were performed in all cases.The scan technique and post-reconstruction experience was summarized.The image quality was classified as 1 to 4 points,and coronary segments classified according to the American Heart Association standards were evaluated.Results The average calcium score of the 600 cases was 213.6±298.7(0-3 216.5).The average heart rate of the enhanced scan was 82.1±16.2(47-139) bpm.The post-reconstruction methods with which coronary segments could be shown as best as possible consisted of single phase reconstruction method,two or more phases supplemented method,and electrocardiogram editing method.Altogether 8 457 coronary segments were evaluated,among which 97.2% were evaluated as point 1,1.7% point 2,0.5% point 3,and 0.6% point 4.The coronary segments in 261 cases were completely normal,while 360 segments were diagnosed with <50% stenosis and 625 segments with ≥50% stenosis.Conclusions Excellent coronary artery image can be obtained with dual source CT in patients with any heart rate without oral metoprolol preparation.Heart rate is not a major source of the artifact,coronary segments can be well shown with single or multiple-phase reconstruction method.