Analysis of coronary angiography related psychophysiological responses

Background

Numerous studies have been conducted regarding a heartbeat classification algorithm over the past several decades. However, many algorithms have also been studied to acquire robust performance, as biosignals have a large amount of variation among individuals. Various methods have been proposed to reduce the differences coming from personal characteristics, but these expand the differences caused by arrhythmia.

Methods

In this paper, an arrhythmia classification algorithm using a dedicated wavelet adapted to individual subjects is proposed. We reduced the performance variation using dedicated wavelets, as in the ECG morphologies of the subjects. The proposed algorithm utilizes morphological filtering and a continuous wavelet transform with a dedicated wavelet. A principal component analysis and linear discriminant analysis were utilized to compress the morphological data transformed by the dedicated wavelets. An extreme learning machine was used as a classifier in the proposed algorithm.

Results

A performance evaluation was conducted with the MIT-BIH arrhythmia database. The results showed a high sensitivity of 97.51%, specificity of 85.07%, accuracy of 97.94%, and a positive predictive value of 97.26%.

Conclusions

The proposed algorithm achieves better accuracy than other state-of-the-art algorithms with no intrasubject between the training and evaluation datasets. And it significantly reduces the amount of intervention needed by physicians.     

Measurement of coronary bifurcation angle with coronary CT angiography: A phantom study

PurposeAccurate determination of the bifurcation angle and correlation with plaque buildup may lead to the prediction of coronary artery disease (CAD). This work evaluates two techniques to measure bifurcation angles in 3D space using coronary computed tomography angiography (CCTA).Materials and MethodsNine phantoms were fabricated with different bifurcation angles ranging from 55.3° to 134.5°. General X-ray and CCTA were employed to acquire 2D and 3D images of the bifurcation phantoms, respectively. Multiplanar reformation (MPR) and volume rendering technique (VRT) were used to measure the bifurcation angle between the left anterior descending (LAD) and left circumflex arteries (LCx). The measured angles were compared with the true values to determine the accuracy of each measurement technique. Inter-observer variability was evaluated. The two techniques were further applied on 50 clinical CCTA cases to verify its clinical value.ResultsIn the phantom setting, the mean absolute differences calculated between the true and measured angles by MPR and VRT were 2.4° ± 2.2° and 3.8° ± 2.9°, respectively. Strong correlation was found between the true and measured bifurcation angles. Furthermore, no significant differences were found between the bifurcation angles measured using either technique. In clinical settings, large difference of 12.0° ± 10.6° was found between the two techniques.ConclusionIn the phantom setting, both techniques demonstrated a significant correlation to the true bifurcation angle. Despite the lack of agreement of the two techniques in the clinical context, our findings in phantoms suggest that MPR should be preferred to VRT for the measurement of coronary bifurcation angle by CCTA.     

Current principles in the use of diagnostic coronary angiography

The paper presents current principles in designing diagnostic coronary angiography by taking into account of fundamental achievements in endovascular medicine in diagnosing and treating various heart diseases. Analyzing the world and Russian experience gained, the authors present basic qualitative and quantitative requirements for X-ray contrast study of cardiac vessels to enhance the information value of coronary angiography. They consider necessary diagnostic criteria to be achieved during the study to choose a surgical or endovascular treatment: a type and number of diagnostic film projections, X-ray anatomy of coronary vessels. The present-day accumulated data on X-ray anatomic features of coronary vessels in coronary heart disease are classified. Current classifications of coronary circulation, principles in the development of collateral blood supply, main sources of collaterals, and the specific features of the coronary bed in patients with coronary heart disease are also given.     

Efficacy and safety of coronary stenting during diagnostic coronary angiography in patients with stable angina

The authors assessed the in-hospital and long-term (up to 6 months) results of coronary stenting conducted just after diagnostic coronarography during a common procedure in patients with stable angina pectoris on effort. The 2001-2002 study included 2277 patients. The clinical indications for catheterization were Functional Classes II-IV stable angina on effort in 83 % of patients and silent ischemia in 17%. The study excluded patients with previous coronarography, acute coronary syndrome on admission, renal failure, left ventricular ejection fraction <30%, and left trunk stenosis. All the patients received aspirin and clopidogrel before catheterization. RESULTS: 57% of patients had multivessel disease; full revascularization was performed in 59% of the patients with multivessel disease. The coronary intervention was successful in 100% of cases. Significant in-hospital events (myocardial infarction without Q wave) were in 1.2% of cases. The mean length of hospital stay was 2.9 +/- 2.4 days. The rate of stent thrombosis for as long as 30 days was 0.2%. Recurrent angina and/or positive exercise tests were in 12% during 6 months. CONCLUSION: immediate stening is effective and safe in most patients with stable angina during diagnostic catheterization. It does not increase immediate and late complications.     

Incidence and severity of coronary artery disease in patients with atrial fibrillation undergoing first-time coronary angiography

Background

In standard reference sources, the incidence of coronary artery disease (CAD) in patients with atrial fibrillation (AF) ranged between 24 and 46.5%. Since then, the incidence of cardiovascular risk factors (CRF) has increased and modern treatment strategies (“pill in the pocket”) are only applicable to patients without structural heart disease. The aim of this study was to investigate the incidence and severity of CAD in patients with AF.

Methods

From January 2005 until December 2009, we included 261 consecutive patients admitted to hospital with paroxysmal, persistent or permanent AF in this prospective study. All patients underwent coronary angiography and the Framingham risk score (FRS) was calculated. Patients with previously diagnosed or previously excluded CAD were excluded.

Results

The overall incidence of CAD in patients presenting with AF was 34%; in patients >70 years, the incidence of CAD was 41%. The incidence of patients undergoing a percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) was 21%. Patients with CAD were older (73±8 years vs 68±10 years, p = 0.001), had significantly more frequent hypercholesterolemia (60% vs 30%, p<0.001), were more frequent smokers (26% vs 13%, p = 0.017) and suffered from angina more often (37% vs 2%, p<0.001). There was a significant linear trend among the FRS categories in percentage and the prevalence of CAD and PCI/CABG (p<0.0001).

Conclusions

The overall incidence of CAD in patients presenting with AF was relatively high at 34%; the incidence of PCI/CABG was 21%. Based upon increasing CRF in the western world, we recommend a careful investigation respecting the FRS to either definitely exclude or establish an early diagnosis of CAD – which could contribute to an early and safe therapeutic strategy considering type Ic antiarrhythmics and oral anticoagulation.     

Multimodality imaging of borderline left main coronary disease using fluoroscopy, IVUS and CT coronary angiography

A borderline left main narrowing was discovered during coronary angiography in a young asymptomatic man with positive stress test. IVUS demonstrated minimal diameter of 2.9 mm and the cross-sectional area was 11.5 mm(2). CTs were performed, and an eccentric calcific plaque was imaged at the ostium of the left main. Based on all three image modalities after discussing the different therapeutic options with the patient he was referred for bypass surgery.     

Elderly and younger patients selected to undergo coronary angiography.

OBJECTIVE--To establish and compare the characteristics of older (greater than or equal to 70 years) and younger patients with chest pain selected to undergo coronary angiography and by analysis of their subsequent management to assess the value of coronary angiography for older patients with chest pain. DESIGN--Retrospective analysis of clinical case notes and coronary angiography reports. SETTING--Cardiology department with referral population of one million in an Edinburgh hospital. PATIENTS--134 consecutive patients with chest pain aged 70 years or over investigated by coronary angiography between 1978 and 1988; 134 randomly selected patients aged under 70 investigated over the same period. MAIN OUTCOME MEASURES--Clinical and angiographic features at time of angiography and management after angiography. RESULTS--Older patients represented a small, but increasing, proportion of those investigated. Older patients had more severe symptoms at the time of angiography, were taking more antianginal drugs, and had had their symptoms for longer than younger patients. At angiography more older patients had triple vessel coronary disease, left main stem stenosis, or left ventricular impairment. After angiography similar proportions of older and younger patients underwent coronary artery surgery, with more elderly patients requiring urgent operation; although operative mortality was higher for elderly patients, symptomatic benefit was similar to that in younger patients. CONCLUSIONS--Older patients with angina selected to undergo coronary angiography and subsequent coronary surgery have more severe symptoms and underlying cardiac disease. Earlier referral and investigation might yield a population with lower operative risk. Selection of patients for coronary angiography and coronary artery surgery should be based on the potential for benefit and should avoid "agism."     

Three-dimensional spatial reconstruction of coronary arteries based on fusion of intravascular optical coherence tomography and coronary angiography

We present a three-dimensional (3D) spatial reconstruction of coronary arteries based on fusion of intravascular optical coherence tomography (IVOCT) and digital subtraction angiography (DSA). Centerline of vessel in DSA images is exacted by multi-scale filtering, adaptive segmentation, morphology thinning and Dijkstra's shortest path algorithm. We apply the cross-correction between lumen shapes of IVOCT and DSA images and match their stenosis positions to realize co-registration. By matching the location and tangent direction of the vessel centerline of DSA images and segmented lumen coordinates of IVOCT along pullback path, 3D spatial models of vessel lumen are reconstructed. Using 1121 distinct positions selected from eight vessels, the correlation coefficient between 3D IVOCT model and DSA image in measuring lumen radius is 0.94% and 97.7% of the positions fall within the limit of agreement by Bland–Altman analysis, which means that the 3D spatial reconstruction IVOCT models and DSA images have high matching level.     

运动试验假阴性而冠状动脉造影阳性冠心病的特点分析

目的:探讨平板运动试验(TET)假阴性而冠状动脉造影(CAG)阳性冠心病病例的特点.方法:对同期内(相距时间1周)TET阴性而有心前区不适者进行CAG的冠心病患者60例(男性42例,女性18例,平均年龄66±10.岁)进行回顾性分析.TET以运动中及恢复期R波为主的导联出现ST段水平型下移0.05mV为阴性标准.CAG以冠状动脉狭窄直径≥50%为阳性标准.结果:60例患者CAG共累计病变106处,其中左主干2例2处、左前降支21例30处、左回旋支7例13处、右冠状动脉27例36处、对角支7例10处、间隔支3例3处、钝缘支3例3处、后降支6例6处、中间支2例3处.病变范围在在50%～74%占65处、病变范围在75%～89%占30处、病变范围在90%～95%占11处.冠状动脉单支病变40例(占66.7%),以右冠状动脉及左前降支为多,占70.0%(28/40),双支病变14例(占23.3%),左前降支+右冠状动脉较多,占57.1%(8/14),三支病变6例(占10.0%).60例患者中有侧支循环者31例(51.7%).有16 例(26.7%)试验运动量不足,男性明显多于女性(P<0.05).结论:冠心痛患者TET假阴性的因为可能为冠脉病变小、狭窄程度轻、狭窄病变供血心肌建立了良好的侧支循环以及试验运动量不够.对于有临床症状而TET阴性的患者应行CAG检查,以明确诊断.     

Selection of optimal cardiac phases for ECG-triggered coronary CT angiography in pediatrics

PurposeThe use of coronary computed tomography angiography (CCTA) in children remains limited by patient’s irradiation, and motion artefacts impairing image quality. Triggering the acquisition at the appropriate moment, and acquiring only necessary components of the cardiac cycle could overcome these limitations. Yet, optimal cardiac intervals to perform CCTA as a function of heart rate (HR) have not yet been addressed in pediatrics.MethodsFifty children with coronary artery anomalies underwent a CCTA on a wide-coverage single-beat CT scanner. Multiple phases from 25% to 85% of the R-R interval were acquired and reconstructed with 10% increments. Two radiologists independently assessed motion artifacts on each cardiac phase using a 4-point semi-quantitative scale.ResultsAt patient level, the best phase for acquisition was found in diastole for patients with HR ≤ 75 bpm and in systole for patients with HR > 85 bpm. At coronary segments and structures level, median optimal phases were reported at 70%, 80%, 47%, 50%, and 54% of the R-R interval for patients with HR ≤ 60, 61–75, 86–100, 101–130, and >130 bpm respectively. For patients with HR between 76 and 85 bpm, no clear trend could be observed. Optimal acquisition durations represented 10% (2 phases), 20% (3 phases), 50% (multiphase), 20% (3 phases), and 10% (2 phases) of the R-R interval for patients with HR ≤ 60, 61–75, 76–100, 101–130, and >130 bpm, respectively.ConclusionsOptimal positioning and duration of CCTA acquisition intervals were investigated as a function of children’s HR, to reduce motion artifacts and patient’s irradiation.     

Coronary CT angiography for suspected acute coronary syndrome: sex-associated differences

AimThe optimal diagnostic test in the work-up of suspected acute coronary syndrome (ACS) may differ between men and women. The aim of this study was to compare sex-associated differences between using a diagnostic strategy including early coronary computed tomography angiography (CCTA) and standard of care (SOC).MethodsIn total, 500 patients who presented with symptoms suggestive of ACS at the emergency department were randomised between a diagnostic strategy supplemented with early CCTA and SOC.ResultsWomen were generally older than men (mean ± standard deviation 56 ± 10 vs 53 ± 10 years, p < 0.01) and were less often admitted to hospital (33% vs 44%, p = 0.02). Obstructive coronary artery disease on CCTA (> 50% luminal narrowing) was less frequently seen in women (14% vs 26%, p = 0.02), and ACS was diagnosed less often in women (5% vs 10%, p = 0.03). Women underwent less outpatient testing when early CCTA was used in the emergency department evaluation of suspected ACS (p = 0.008).ConclusionWomen had a lower incidence of obstructive CAD on CCTA and were less often admitted to hospital than men. They were subjected to less outpatient testing when early CCTA was used in the emergency department evaluation of suspected ACS.Supplementary InformationThe online version of this article (10.1007/s12471-021-01607-1) contains supplementary material, which is available to authorized users.     

Early exercise testing and coronary angiography after uncomplicated myocardial infarction.

In a prospective study 61 patients aged 55 years or less with uncomplicated myocardial infarction underwent treadmill stress testing at two weeks and coronary angiography at six weeks after infarction. Of the 44 patients who had a positive stress test, 43 had additional severe coronary artery disease confirmed by coronary angiography. Of the 17 patients who had a negative stress test for additional disease, coronary angiography identified only single-vessel disease in the infarct area in 15. The sensitivity of the stress test was 95% and the specificity 94%, though the number of patients in the study was small. Thus, exercise testing has considerable potential for the early identification of multiple-vessel disease in patients with uncomplicated myocardial infarction.