Coronary arterial bypass graft patency evaluated by multi-detector computed tomography and magnetic resonance imaging

The progression of atherosclerosis of the coronary artery does not stop after coronary arterial bypass grafting (CABG) surgery.……

Intravascular photoacoustic and optical coherence tomography imaging dual-mode system for detecting spontaneous coronary artery dissection: A feasibility study

In this work,we present an intravascular dual-mode endoscopic system capable of both intravascular photoacoustic imaging(IVPAI)and intravascular optical coherence tomography(IVOCT)for recognizing spontaneous coronary artery dissection(SCAD)phantoms.IVPAI provides high-resolution and high-penetration images of intramural hematoma(IMH)at different depths,so it is especially useful for imaging deep blood clots associated with imaging phantoms.IVOCT can readily visualize the double-lumen morphology of blood vessel walls to identify intimal tears.We also demonstrate the capability of this dual-mode endoscopic system using mimicking phantoms and biological samples of blood clots in ex vivo porcine arteries.The results of the experiments indicate that the combined IVPAI and IVOCT technique has the potential to provide a more accurate SCAD assessment method for clinical applications.

Effects of sevoflurane on left ventricular function by speckletracking echocardiography in coronary bypass patients: A randomized trial

The present study aimed to dynamically observe the segmental and global myocardial movements of the left ventricle during coronary artery bypass grafting by transesophageal speckle-tracking echocardiography,and to assess the effect of sevoflurane on cardiac function.Sixty-four patients scheduled for the off-pump coronary artery bypass grafting were randomly divided into a sevoflurane-based anesthesia(AS)group and a propofolbased total intravenous anesthesia(AA)group.The AS group demonstrated a higher absolute value of left ventricular global longitudinal strain than that of the AA group at both T1(after harvesting all grafts and before coronary anastomosis)and T_(2)(30 min after completing all coronary anastomoses)(P<0.05).Moreover,strain improvement in the segment with the highest preoperative strain was significantly reduced in the AS group,compared with the AA group at both T1 and T_(2)(P<0.01).The flow of the left internal mammary artery-left anterior descending artery graft was superior,and the postoperative concentration of troponin T decreased rapidly in the AS group,compared with the AA group(P<0.05).Compared with total intravenous anesthesia,sevoflurane resulted in a significantly higher global longitudinal strain,stroke volume,and cardiac output.Sevoflurane also led to an amelioration in the condition of the arterial graft.Furthermore,sevoflurane significantly reduced strain improvement in the segmental myocardium with a high preoperative strain value.The findings need to be replicated in larger studies.

Challenging situation of coronary artery anomaly associated with ischemia and/or risk of sudden death

Coronary artery anomaly is known as one of the causes of angina pectoris and sudden death and is an important clinical entity that cannot be overlooked.The incidence of coronary artery anomalies is as low as 1%-2%of the general population,even when the various types are combined.Coronary anomalies are practically challenging when the left and right coronary ostium are not found around their normal positions during coronary angiography with a catheter.If there is atherosclerotic stenosis of the coronary artery with an anomaly and percutaneous coronary intervention(PCI)is required,the suitability of the guiding catheter at the entrance and the adequate back up force of the guiding catheter are issues.The level of PCI risk itself should also be considered on a caseby-case basis.In this case,emission computed tomography in the R-1 subtype single coronary artery proved that ischemia occurred in an area where the coronary artery was not visible to the naked eye.Meticulous follow-up would be crucial,because sudden death may occur in single coronary arteries.To prevent atherosclerosis with full efforts is also important,as the authors indicated admirably.

Effect of cardiac rehabilitation care after coronary intervention on cardiac function recovery and negative mood in patients with myocardial infarction

BACKGROUND Cardiovascular disease,particularly myocardial infarction(MI)profound impact on patients'quality of life and places a substantial burden on the healthcare and economy systems.Developments in medical technology have led to the emer-gence of coronary intervention as an essential method for treating MI.AIM To assess the effects of cardiac rehabilitation care on cardiac function recovery and negative emotions in MI after coronary intervention.METHODS This study included a total of 180 patients with MI during the period from June 2022 to July 2023.Selected patients were divided into two groups:An observation group,which receiving cardiac rehabilitation care;a control group,which re-ceiving conventional care.By comparing multiple observation indicators such as cardiac function indicators,blood pressure,exercise tolerance,occurrence of adverse cardiac events,and negative emotion scores between the two groups of patients.All the data were analyzed and compared between two groups.RESULTS There were 44 males and 46 females in the observation group with an average age of 36.26±9.88 yr;there were 43 males and 47 females in the control group,with an average age of 40.87±10.5 yr.After receiving the appropriate postoperative nursing measures,the results of the observation group showed significant improvement in several indicators compared with the control group.Indicators of cardiac function,such as left ventricular end-diastolic internal diameter and left ventricular ejection fraction were significantly better in the observation group than in the control group(P<0.05).Exercise endurance assessment showed that the 6-minute walking test distance was significantly increased in the patients of the observation group(P<0.01).In addition,the incidence of adverse cardiac events was significantly lower in the observation group,and negative mood scores were significantly reduced(P<0.05).CONCLUSION Cardiac rehabilitation care after coronary intervention has a significant positive impact on functional recovery.This emphasizes the importance of cardiac rehabilitation care to improve patient recovery.

Myosteatosis is associated with coronary artery calcification in patients with type 2 diabetes

BACKGROUND Myosteatosis,rather than low muscle mass,is the primary etiologic factor of sarcopenia in patients with type 2 diabetes mellitus(T2DM).Myosteatosis may lead to a series of metabolic dysfunctions,such as insulin resistance,systematic inflammation,and oxidative stress,and all these dysfunctions are closely associated with the acceleration of T2DM and atherosclerosis.AIM To investigate the association between myosteatosis and coronary artery calcification(CAC)in patients with T2DM.METHODS Patients with T2DM,who had not experienced major cardiovascular events and had undergone both abdominal and thoracic computed tomography(CT)scans,were included.The mean skeletal muscle attenuation was assessed using abdominal CT images at the L3 level.The CAC score was determined from thoracic CT images using the Agatston scoring method.Myosteatosis was diagnosed according to Martin’s criteria.Severe CAC(SCAC)was defined when the CAC score exceeded 300.Logistic regression and decision tree analyses were performed.RESULTS A total of 652 patients with T2DM were enrolled.Among them,167(25.6%)patients had SCAC.Logistic regression analysis demonstrated that myosteatosis,age,duration of diabetes,cigarette smoking,and alcohol consumption were independent risk factors of SCAC.Myosteatosis was significantly associated with an increased risk of SCAC(OR=2.381,P=0.003).The association between myosteatosis and SCAC was significant in the younger patients(OR=2.672,95%CI:1.477-4.834,P=0.002),but not the older patients(OR=1.456,95%CI:0.863-2.455,P=0.188),and was more prominent in the population with lower risks of atherosclerosis.The decision tree analyses prioritized older age as the primary variable for SCAC.In older patients,cigarette smoking was the main contributing factor for SCAC,while in younger patients,it was myosteatosis.CONCLUSION Myosteatosis is a novel risk factor for atherosclerosis in patients with T2DM,especially in the population with younger ages and fewer traditional risk factors.

Nε-carboxymethyl-lysine and inflammatory cytokines,markers and mediators of coronary artery disease progression in diabetes

This editorial refers to the article“Comparative analysis of Nε-carboxymethyllysine and inflammatory markers in diabetic and non-diabetic coronary artery disease patients”,published in the recent issue of the World Journal of Diabetes 2023 is based on glucose metabolism,advanced glycation end products(AGEs),inflammation and adiposity on diabetes and coronary artery disease(CAD).This study has included CAD patients who were stratified according to glycosylated hemoglobin higher than 6.5 and sex-matched.A higher prevalence of hypertension,dyslipidemia,and non-vegetarian diet were found in the diabetic group.These risk factors might influence body weight and adiposity and explain the increment of the left atrium.Although this data was not supported by the study.The diet can also explain the non-enzymatic reactions on lipids,proteins,or nucleic acids and consequently an increment of AGEs.These molecules can emit fluorescence.However,one of the non-fluorescent and most abundant AGEs is Nε-carboxymethyl-lysine(CML).Its association with coronary artery stenosis and severity in the diabetic group might suggest its role as a player in CAD progression.Thus,CML,after binding with its receptor(RAGE),can induce calcification cascade through reactive oxygen species and mitogen-activated protein kinase.Moreover,this interaction AGE-RAGE can cause activation of the transcription nuclear factor-kb and induce inflammatory cytokines.It might explain the relationship between CML and pro-inflammatory cytokines in diabetic and CAD patients.Although this is a population from one center,the determination of CML and inflammatory cytokines might improve the diagnosis of severe and progressive CAD.Future and comparative studies among glycosylated hemoglobin,CML,and other AGE levels according to diagnosis and prognosis value might modify the clinical practice.Although these molecules are irreversible,they can act through a specific receptor inducing a signal transduction that might be modulated by inhibitors,antibodies,or siRNA.Further mechanistic studies might improve the development of future preventive therapies for diabetic patients.

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.

Correlation of neutrophil to lymphocyte ratio to severity of coronary artery disease and in-hospital clinical outcomes in patients with acute coronary syndrome: A prospective observational study

Objective:To explore correlation of neutrophil-to-lymphocyte ratio(NLR)to severity of coronary artery disease(CAD)and in-hospital clinical outcomes in patients with acute coronary syndrome(ACS).Methods:In this prospective and observational study,we recruited 500 patients with ACS.For all the eligible patients,demographic details were collected,and laboratory parameters were evaluated.The CAD severity was evaluated in terms of the number of involved vessels.The NLR was calculated based on neutrophils and lymphocytes and the correlation of various risk factors and severity and outcome of CAD was performed.Results:77.2%of Patients was male,and 52%of the patients aged between 55-70 years.Based on the type of ACS,396 out of 500 patients had ST-elevation myocardial infarction.An ascending trend in the white blood cell levels and NLR value was noted as the severity of the ACS increased and the highest white blood cell levels and NLR was noted among classⅣpatients.The mean NLR value among the non-survivors were higher compared to the survivors(9.52±5.72 vs.4.76±2.36;P<0.01).Receiver operating curve showed that the cut-off NLR value was 5.76 with a sensitivity of 75.0%and a specificity of 77.3%.Conclusions:The NLR can be used as an independent prognostic marker in ACS.An elevated NLR value serves as a reliable predictor for short-term complications,notably in-hospital mortality.

Spontaneous coronary artery rupture after lung cancer surgery:A case report and review of literature

BACKGROUND Spontaneous coronary artery rupture(SCAR)is a rare and life-threatening complication after lung cancer surgery.We present a case of SCAR following left upper lobectomy,successfully managed through emergency thoracotomy and coronary artery ligation.CASE SUMMARY A 61-year-old male patient underwent left upper lobectomy and mediastinal lymph node dissection for lung cancer.The surgery was performed using singleport video-assisted thoracoscopic surgery,and there were no observed complications during the procedure.However,19 h after surgery,the patient experienced chest discomfort and subsequently developed severe symptoms,including nausea,vomiting,and a drop in blood pressure.Urgent measures were taken,leading to the diagnosis of SCAR.The patient underwent emergency thoracotomy and coronary artery ligation,successfully stopping the bleeding and stabilizing the condition.Despite postoperative complications,the patient made a successful recovery and was discharged from the hospital.CONCLUSION SCAR is a rare but life-threatening complication following lung cancer surgery.Immediate thoracotomy has been shown to be a life-saving measure,while stenting is not the preferred initial approach.

Efficacy of laparoscopic low anterior resection for colorectal cancer patients with 3D-vascular reconstruction for left coronary artery preservation

BACKGROUND Laparoscopic low anterior resection(LLAR)has become a mainstream surgical method for the treatment of colorectal cancer,which has shown many advantages in the aspects of surgical trauma and postoperative rehabilitation.However,the effect of surgery on patients'left coronary artery and its vascular reconstruction have not been deeply discussed.With the development of medical imaging technology,3D vascular reconstruction has become an effective means to evaluate the curative effect of surgery.AIM To investigate the clinical value of preoperative 3D vascular reconstruction in LLAR of rectal cancer with the left colic artery(LCA)preserved.METHODS A retrospective cohort study was performed to analyze the clinical data of 146 patients who underwent LLAR for rectal cancer with LCA preservation from January to December 2023 in our hospital.All patients underwent LLAR of rectal cancer with the LCA preserved,and the intraoperative and postoperative data were complete.The patients were divided into a reconstruction group(72 patients)and a nonreconstruction group(74 patients)according to whether 3D vascular reconstruction was performed before surgery.The clinical features,operation conditions,complications,pathological results and postoperative recovery of the two groups were collected and compared.RESULTS A total of 146 patients with rectal cancer were included in the study,including 72 patients in the reconstruction group and 74 patients in the nonreconstruction group.There were 47 males and 25 females in the reconstruction group,aged(59.75±6.2)years,with a body mass index(BMI)(24.1±2.2)kg/m2,and 51 males and 23 females in the nonreconstruction group,aged(58.77±6.1)years,with a BMI(23.6±2.7)kg/m2.There was no significant difference in the baseline data between the two groups(P>0.05).In the submesenteric artery reconstruction group,35 patients were type I,25 patients were type II,11 patients were type III,and 1 patient was type IV.There were 37 type I patients,24 type II patients,12 type III patients,and 1 type IV patient in the nonreconstruction group.There was no significant difference in arterial typing between the two groups(P>0.05).The operation time of the reconstruction group was 162.2±10.8 min,and that of the nonreconstruction group was 197.9±19.1 min.Compared with that of the reconstruction group,the operation time of the two groups was shorter,and the difference was statistically significant(t=13.840,P<0.05).The amount of intraoperative blood loss was 30.4±20.0 mL in the reconstruction group and 61.2±26.4 mL in the nonreconstruction group.The amount of blood loss in the reconstruction group was less than that in the control group,and the difference was statistically significant(t=-7.930,P<0.05).The rates of anastomotic leakage(1.4%vs 1.4%,P=0.984),anastomotic hemorrhage(2.8%vs 4.1%,P=0.672),and postoperative hospital stay(6.8±0.7 d vs 7.0±0.7 d,P=0.141)were not significantly different between the two groups.CONCLUSION Preoperative 3D vascular reconstruction technology can shorten the operation time and reduce the amount of intraoperative blood loss.Preoperative 3D vascular reconstruction is recommended to provide an intraoperative reference for laparoscopic low anterior resection with LCA preservation.

Implications of Elevated Serum Cortisol in the Onset of Postoperative Delirium Following Off-Pump Coronary Artery Bypass Grafting: Insights from a Bangladesh-Based Single Center Experience

Background: Following coronary artery bypass grafting (CABG), delirium emerges as a prevalent complication. This study aimed to assess the correlation between elevated serum cortisol levels and the occurrence of postoperative delirium subsequent to off-pump CABG. Methods: Conducted in the Department of Cardiac Surgery at BSMMU from October 2020 to September 2022, this comparative cross-sectional study included a total of 44 participants. Subjects, meeting specific criteria, were purposefully assigned to two groups based on off-pump CABG. Group A (n = 22) consisted of patients with normal serum cortisol levels, while Group B (n = 22) comprised individuals with high serum cortisol levels on the first postoperative day. Delirium onset was assessed at the bedside in the ICU on the 1st, 2nd, 3rd, 4th, and 5th postoperative days using standard tools, namely the Richmond Agitation Sedation score (RASS) and The Confusion Assessment Method (CAM-ICU). Data were collected based on the presence or absence of delirium. Statistical analysis utilized SPSS version 26.0, employing an independent Student’s t-test for continuous data and chi-square and Fischer’s exact test for categorical data. A p-value ≤ 0.05 was considered statistically significant. Results: Group-A had a mean age of 54.50 ± 17.97, and Group-B had a mean age of 55.22 ± 15.45, both with a male predominance (81.81% and 86.36% respectively). The mean serum cortisol level was significantly higher in Group B (829.71 ± vs. 389.98 ± 68.77). Postoperative delirium occurred in 27.3% of Group B patients, statistically significant compared to the 4.5% in Group A. However, patients in Group B who developed delirium experienced significantly longer postoperative ICU and hospital stays (79.29 ± 12.27 vs. 11.44 ± 2.85, p ≤ 0.05). There was one mortality in Group B, which was statistically not significant. Conclusion: This study observed a significant association between elevated serum cortisol levels in the postoperative period and the occurrence of postoperative delirium after off-pump coronary artery bypass grafting.

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.

Role of lymphocyte-to-monocyte ratio as a predictive marker for diabetic coronary artery disease: A cross-sectional study

BACKGROUND The lymphocyte to monocyte ratio(LMR)is considered a marker of systemic inflammation in cardiovascular disease and acts as predictor of mortality in coronary artery disease.AIM To investigate the predictive role of LMR in diabetic coronary artery disease patients.METHODS This cross-sectional study was conducted at tertiary care super-specialty hospital at New Delhi,India.A total of 200 angiography-proven coronary artery disease(CAD)patients were enrolled and grouped into two categories:Group I[CAD patients with type 2 diabetes mellitus(T2DM)and glycated hemoglobin(HbA1c)levels≥6.5%],and Group II(CAD patients without T2DM and HbA1c levels<6.5%).Serum lipoproteins,HbA1c,and complete blood count of enrolled patients were analyzed using fully automatic analyzers.RESULTS The logistic regression analysis showed an odds ratio of 1.48(95%CI:1.28-1.72,P<0.05)for diabetic coronary artery disease patients(Group I)in unadjusted model.After adjusting for age,gender,diet,smoking,and hypertension history,the odds ratio increased to 1.49(95%CI:1.29-1.74,P<0.01)in close association with LMR.Further adjustment for high cholesterol and triglycerides yielded the same odds ratio of 1.49(95%CI:1.27-1.75,P<0.01).Receiver operating characteristic curve analysis revealed 74%sensitivity,64%specificity,and 0.74 area under the curve(95%CI:0.67-0.80,P<0.001),suggesting moderate predictive accuracy for diabetic CAD patients.CONCLUSION LMR showed positive association with diabetic coronary artery disease,with moderate predictive accuracy.These findings have implications for improving CAD management in diabetics,necessitating further research and targeted interventions.

Unroofing Technique for Anomalous Origin of the Left Coronary Artery from the Right Sinus of Valsalva: Report of a Case

Anomalous origin of the left coronary artery (AOLCA) from the right sinus of Valsalva constitutes a rare congenital coronary artery anomaly. Patients with an anomalous left main coronary artery face a significantly higher risk of sudden cardiac death compared to those with an anomalous right coronary artery. The anomalous coronary artery traversing between the ascending aorta and the pulmonary artery markedly heightens the risk of myocardial ischemia, arrhythmia, and sudden death. Symptomatic patients often exhibit a longer intramural course of the coronary artery, which may necessitate earlier intervention or influence the choice of surgical repair method. Surgical intervention is advocated for patients with this anomaly, even in the absence of symptoms. For anomalous aortic origin of a coronary artery from the opposite sinus of Valsalva with an intramural course, coronary unroofing is the preferred revascularization procedure. This report presents a case of AOLCA originating from the right sinus of Valsalva, treated surgically using the unroofing technique for the aortic intramural segment of the anomalous coronary artery traversing between the great vessels. The unroofing technique is recommended for treating AOLCA with an extensive intramural course that does not involve the commissure.

Employing a random forest model to forecast the likelihood of coronary artery lesions in Kawasaki disease: a study centered on four biomarkers

Background:Kawasaki disease is an acute immune vasculitis,which is more common in children under 5 years old.Kawasaki disease mainly affects the cardiovascular system,especially the coronary arteries.Once coronary artery damage occurs,it can significantly impact the patient’s prognosis.Therefore,in some countries and regions,Kawasaki disease has become a common acquired heart disease.Methods:First,univariate analysis was conducted on each predictive factor.Then,Least Absolute Shrinkage and Selection Operator and random forest algorithms were used to screen all predictive factors,and the prediction model was evaluated using receiver operating characteristic curve,calibration curve,and Decision Curve Analysis.Results:This study,based on data from 228 Kawasaki disease patients,utilized a random forest model to identify four predictive factors:white blood cell count,creatine kinase isoenzyme MB,albumin,and neutrophil count.These factors were used to construct a prediction model,which achieved an area under the curve of 0.743.Conclusions:We developed a forest plot based on white blood cell count,creatine kinase isoenzyme MB,albumin,and neutrophil count to effectively predict the occurrence of coronary artery lesions in Kawasaki disease.

Application Effect of Blended Education Strategy Based on the Learning Pass Platform in Phase III Cardiac Rehabilitation of Patients with Coronary Artery Disease

Objective:To explore the application effect of the blended education strategy based on the Learning Pass platform in the phase III cardiac rehabilitation of patients with coronary artery disease.Methods:90 patients diagnosed with coronary artery disease in the Department of Cardiology of our hospital from January 2019 to January 2021 were selected and divided into the control group and the experimental group according to the method of randomized numerical table,with 45 cases in each group.Both the experimental group and the control group received pre-discharge cardiac rehabilitation education by conventional means.The control group received education and supervision information via WeChat after discharge,while the experimental group joined the Learning Pass platform to receive online and offline hybrid education and supervision,with online as the mainstay and offline as a supplement.The disease cognitive level,self-management skills,quality of life,medication adherence,and emotional status of the two groups were compared.Results:The disease cognitive levels in the experimental group were significantly higher than those of the control group(P<0.05);the scores of the experimental group in terms of quality of life,self-management skills,and medication adherence were significantly higher than those of the control group(P<0.05);and the scores of anxiety and depression in the experimental group were significantly lower than those of the control group(P<0.05).Conclusion:The blended education strategy based on the Learning Pass platform has a significant application effect in phase III cardiac rehabilitation of patients with coronary artery disease.It can improve patients’disease cognitive level,self-management skills,and quality of life,and provide a basis for improving patients’prognosis.

Predictors of inaccurate coronary arterial stenosis assessment by CT angiography

ABSTRACT Objectives This study sought to investigate the clinical and imaging characteristics associated with diagnostic inaccuracy of computed tomography angiography （CTA） for detecting obstructive coronary artery disease （CAD） defined by quantitative coronary angiography （QCA）.

Contribution of L-type Ca^(2+) channel to the regulation of coronary arterial smooth muscle contraction is different in rats and mice

Background L-type calcium channel participates in the regulation of a variety of physical and pathological process. In vasculature, it mainly mediated agonist-induced vascular smooth muscle contraction. However, it is not clear whether there are differences in L-type calcium channel mediated vessel responses to certain vasoconstrictors among different species. Methods The coronary arteries were dissected from the heart of rats and mice respectively. The coronary arterial ring contraction was measured by Multi Myograph System. Results Endothelin-1, U46619 and 5-HT could produce concentration-dependent vasoconstriction of coronary arterial rings from rats and mice. Compared with rats, the vessel rings of mice were more sensitive to ET-1 and U46619, and less sensitive to 5-HT. The L-type Ca2~ channel blocker nifedipine could significantly inhibit the coronary artery contractions induced by ET-1, U46619 and 5-HT. The inhibitory effect of i ixM nifedipine on ET-1 and 5-HT-induced coronary artery contractions were stronger in mice than in rats, but its effect on U46619 induced-vessel contractions was much weaker in mice than in rats. Conclusions L-type Ca2＋ channel plays an important role in the coronary arterial contraction, but the responses to vasoconstrictor and L-type Ca2＋ channel blocker are different between rats and mice, thus suggesting that the coronary arteries of rats and mice have different biological characteristics.

Relationship between coronary arterial remodeling and clinical presen tation

To examine the relationship between coronary arterial remodeling and clinical pr esentation Methods A total of 34 patients with acute (10 with recent myocardial infarction and 24 w i th unstable angina) and 26 with stable (8 with old myocardial infarction and 18 with stable angina) coronary syndrome underwent intravascular ultrasound (IVUS) before intervention Target lesions were classified as soft or hard plaques Q uantitative measurements of cross sectional area (CSA) of external elastic memb rane (EEM), lumen and plaque were performed at the lesion site and at the proxim al and distal reference sites Remodeling index (RI) was expressed by the ratio of EEM CSA at the lesion site to the mean EEM CSA of both proximal and distal r eference sites Positive remodeling was defined as RI>1 05 and negative remode ling as RI<0 95 Results Soft plaque was observed more frequently in acute than in stable coronary syndro me (59% vs 31%), whereas hard plaque was more common in stable coronary syndrome (69% vs 41%) ( P =0 03) The EEM CSA (15 11±2 89 mm 2 vs 13 25±3 10 mm 2, P =0 019) and plaque CSA (10 83± 2 62 mm 2 vs 9 30±2 84 mm 2, P =0 035) were significantly greater at target lesions in patients with acute r ather than stable coronary syndrome, while lumen CSA and percent area stenosis w ere similar in both groups RI was significantly higher (1 08±0 16 vs 0 95 ±0 14, P =0 002) and positive remodeling was more frequent in acute corona ry syndrome (53% vs 23%, P =0 019), whereas negative remodeling was more com mon in stable coronary syndrome (58% vs 24%, P =0 007) Conclusions The study indicates that clinical characteristics of patients with coronary arte ry disease depend largely upon underlying types of coronary arterial remodeling