Hemodynamic Significance Of Stenosis Research Articles

Comparison of Hemodynamic Significant Coronary Stenosis Using Artificial Intelligence and Conventional Cross Sectional Area in CT Coronary Angiography

<i>Objectives</i>: This was study was designed to compare the accuracy of estimation of coronary stenosis in patients with stable coronary artery disease using artificial intelligence based technique and conventional cross sectional area method using hemodynamically significant stenosis based on CTFFR as the gold standard for significant ischemia. <i>Background</i>: Although detection of degree of stenosis on coronary angiography as well Computed tomographic angiography (CTA) forms the backbone of management plan of a patient with suspected coronary artery disease there is a discordance in the results between both the techniques for estimation of stenosis as well as 20-30% interobservor variation in the results in the stenosis estimation based on conventional angiography method. So a more robust method is needed using modern techniques like artificial intelligence to address this problem. <i>Methods</i>: CTA’s of 100 consecutive patients of stable coronary artery disease were evaluated for coronary stenosis on per vessel and per patient basis using conventional cross section method and using artificial intelligence with hemodynamic significant stenosis using CT FFR < 0.8 as the gold standard for ischemia and the results compared. <i>Results</i>: Cross sectional area method revealed significant stenosis > 50% in 184 (61.2%) vessels per vessel basis and in 65% on per patient basis while the AI method showed significant stenosis in all the 232 (77.2%) per vessels and in 89% per patient basis out of which 81% were hemodynamically significant. 18% of cases were not assessable by cross section method due to heavy vessel calcifications. Sensitivity and specificity on per patient basis by cross section method and AI method were 80%, 57% and 98% and 90% respectively with a false negative and positive of 19%, 42% by cross section method and 1.3%, 10% by AI method respectively with overall accuracy of 76% and 97% respectively of the two methods. <i>Conclusion</i>: AI method of estimation of coronary stenosis is more accurate and robust than conventional area estimation method in clinical practice especially when patients have higher vessel coronary calcium.

Evaluation of the Fractional Flow Reserve by Computer Tomography Data: Comparison of the Calculated Parameters with the Results of Invasive Measurements.

Aim To create a three-dimensional mathematical model of coronary flow in patients with ischemic heart disease based on findings of computed tomography angiography (CTA) with subsequent calculation of the fractional flow reserve (FFRCTA) and comparison of estimated FFRCTA with FFR reference values measured by coronary angiography (CAG).Material and methods The study included 10 patients with borderline stenosis (50-75 %) as determined by CTA performed with a 640‑slice CT-scanner. Based on CTA findings, three-dimensional mathematical models were constructed for further calculation of FFRCTA. Later, an invasive measurement of FFR (FFRINV) was performed for all patients. FFR values &lt;0.8 indicated the hemodynamic significance of stenosis.Results FFRCTA and FFRINV values differed insignificantly in most cases (n=9) and exceeded 5% in only one case. The regression analysis showed a close correlation between estimated and invasively measured FFR values.Conclusion Preliminary results showed a good consistency of calculated and measured FFR values. Therefore, further development of the method for mathematical modeling of three-dimensional blood flow by CTA findings is promising. Noninvasive evaluation of FFR is particularly relevant for analysis of hemodynamic significance of borderline (50-75 %) coronary stenoses.

Diagnostic efficiency of myocardial perfusion computed tomography with transesophageal pacing in patients with an initial diagnosis of acute coronary syndrome

Introduction. Computed tomography angiography (CTA) is widely used to detect atherosclerotic changes in coronary arteries (CA). However, the method is limited by the impossibility to perform functional assessment of detected stenoses. Perfusion computed tomography of the myocardium (PCT) can be used for this purpose.Aim of the study. To assess diagnostic accuracy of PCT of the myocardium with transesophageal electrocardiostimulation (TEES) and stress-echocardiography (stress-echoCG) with veloergometry (VEM) in detection of transient ischemia in patients with initial diagnosis of “acute coronary syndrome” (ACS) with borderline stenoses (50–75%) in CA in relation to measurements of fractional flow reserve (FFR).Materials and Methods. The study included 30 patients with the initial diagnosis of ACS with borderline (50–75%) stenoses in CA according to CTA or coronary angiography (CAG). Subsequently, they underwent myocardial PCT with 320-row detector with TEES, as well as stress-echoCG with VEM. Invasive FFR measurement was used as a reference method. FFR value &lt; 0.8 indicated hemodynamic significance of stenosis. Myocardial perfusion was assessed visually. Regional myocardial contractility of the left ventricle was assessed by stress-echoCG.Results. All patients were examined according to the stated protocol. PCT with TEES revealed FFR-significant stenoses with sensitivity, specificity, prognostic value of positive result and prognostic value of negative result 56, 93, 90, 65% respectively, stress-echoCG with VEM 62, 93, 91, 68% respectively.Conclusion. Myocardial PCT with TEES enables to detect perfusion defects associated with transient ischemia, and the diagnostic accuracy of the method in comparison with FFR is comparable with the already well-proven stress-echoCG. The use of PCT with TEES in combination with CTA can be considered as a promising diagnostic tool in patients without known coronary anatomy and with suspected ACS.

Computed Tomography Myocardial Perfusion Imaging With Transesophageal Atrial Pacing Stress Test in Patients With Borderline Stenoses in the Coronary Arteries: a Comparison With Fractional Flow Reserve.

Aim To evaluate the diagnostic accuracy of cardiac perfusion computed tomography (PCT) with transesophageal electrocardiostimulation (TE ECS) for detection of ischemia in patients with borderline coronary stenosis (50-75 %) compared to measurements of fractional flow reserve (FFR).Material and methods The study included 25 patients with borderline (50-75 %) coronary stenosis as per data of computed tomography angiography (CTA) or coronary angiography (CAG). Later the patients underwent invasive measurement of FFR and cardiac PCT on a 320-row detector tomograph in combination with the TE ECS stress test. FFR values &lt;0.8 indicated the hemodynamic significance of stenosis. Myocardial perfusion was evaluated visually based on consensus of two experts.Results All patients completed the study protocol. Cardiac pacing duration was 6 min for all patients. Four patients required intravenous administration of atropine sulphate. PCT with TE ECS detected significant for FFR stenoses with sensitivity, specificity, and predictive value of a positive result and predictive value for a negative result of 47, 90, 87, and 53 %, respectively.Conclusion PCT with TE ECS in combination with CTA can be considered as an informative method for simultaneous evaluation of the condition of coronary arteries and detection of myocardial ischemia. This method is particularly relevant for assessing the hemodynamic significance of borderline coronary stenoses.

Prediction of coronary atherosclerosis in young patients with coronary artery disease using a non-invasive biomarker

Aim . To develop a combined biomarker for non-invasive diagnostics of the severity of coronary artery (CA) atherosclerosis in patients with coronary artery disease (CAD) and in those without clinical manifestations of atherosclerosis under 50 years of age using structural and functional parameters of large arteries and the lipid profile. Material and methods . A total of 92 patients with CAD and 28 healthy ones were included. Depending on the results of coronary angiography, patients with CAD were divided into 3 groups: without hemodynamically significant stenosis (HSS) (HSS 1&lt;50% , n=30), with HSS of one CA (HSS 1&gt;50% , n=37), with HSS of 2 and more CA (HSS 2&gt;50% , n=25). The subjects underwent a biochemical blood test, carotid duplex ultrasound, volumetric sphygmography. Results . In individuals with HSS1&lt;50%, lipid metabolism disorders were diagnosed in 63,3% (n=19), in HSS 1&gt;50% group — 78,4% (n=29), in HSS2&gt;50% group — 92% of cases (n=23) (p 1-3 &lt;0,05). Carotid intima-media thickness exceeding the threshold level was found in 40% of patients with HSS 1&lt;50% , in 51% of patients with HSS 1&gt;50% and 64% of patients with HSS 2&gt;50% (p 1-3 &lt;0,05). According to the results of volumetric sphygmography, the severity of CA atherosclerosis was associated with a higher pulse wave velocity and L-/CAVI 1 . At the next stage, a complex parameter for predicting coronary atherosclerosis (CA biomarker) was developed, including sex, structural and functional indicators of the arteries (intima-media thickness, в-stiffness index, L-/CAVI 1 ) and biochemical parameters (total cholesterol, triglycerides, low density lipoproteins). In healthy people, the level of CA biomarker was 2,7 (95% CI, 2,3-3,9); in patients with CAD with any degree of CA lesion — 6,4 (95% CI, 5,2-9,6). The CA biomarker threshold of 5 points with a sensitivity of 87,5% and a specificity of 90,5% was determined as the optimal cut-off point; area under the curve — 0,965 (95% CI, 0,943-0,987) (p&lt;0,0001). Conclusion . In patients with CAD, the presence and degree of coronary atherosclerosis are associated with the deterioration of most structural and functional artery parameters. The developed complex CA biomarker is of interest for non-in-vasive screening of preclinical CA atherosclerosis in patients with a low relative risk.

Impact of machine learning-based coronary computed tomography angiography fractional flow reserve on treatment decisions and clinical outcomes in patients with suspected coronary artery disease.

This study investigated the impact of machine learning (ML)-based fractional flow reserve derived from computed tomography (FFRCT) compared to invasive coronary angiography (ICA) for therapeutic decision-making and patient outcome in patients with suspected coronary artery disease (CAD). One thousand one hundred twenty-one consecutive patients with stable chest pain who underwent coronary computed tomography angiography (CCTA) followed ICA within 90 days between January 2007 and December 2016 were included in this retrospective study. Medical records were reviewed for the endpoint of major adverse cardiac events (MACEs). FFRCT values were calculated using an artificial intelligence (AI) ML platform. Disagreements between hemodynamic significant stenosis via FFRCT and severe stenosis on qualitative CCTA and ICA were also evaluated. After FFRCT results were revealed, a change in the proposed treatment regimen chosen based on ICA results was seen in 167 patients (14.9%). Over a median follow-up time of 26 months (4-48 months), FFRCT ≤ 0.80 was associated with MACE (HR, 6.84 (95% CI, 3.57 to 13.11); p < 0.001), with superior prognostic value compared to severe stenosis on ICA (HR, 1.84 (95% CI, 1.24 to 2.73), p = 0.002) and CCTA (HR, 1.47 (95% CI, 1.01 to 2.14, p = 0.045). Reserving ICA and revascularization for vessels with positive FFRCT could have reduced the rate of ICA by 54.5% and lead to 4.4% fewer percutaneous interventions. This study indicated ML-based FFRCT had superior prognostic value when compared to severe anatomic stenosis on CCTA and adding FFRCT may direct therapeutic decision-making with the potential to improve efficiency of ICA. • ML-based FFRCT shows superior outcome prediction value when compared to severe anatomic stenosis on CCTA. • FFRCT noninvasively informs therapeutic decision-making with potential to change diagnostic workflows and enhance efficiencies in patients with suspected CAD. • Reserving ICA and revascularization for vessels with positive FFRCT may reduce the normalcy rate of ICA and improve its efficiency.

Investigation of the Postoperative Complications Rate and Predictors in Patients Undergoing Surgery due to Associated Carotid and Coronary Occlusive Disease.

The aim of this study was to evaluate the frequency of postoperative complications in patients who underwent coronary artery bypass grafting (CABG) and simultaneous carotid endarterectomy (CEA) and find predictors of postoperative complications. We retrospectively evaluated 86 patients after simultaneous CABG and CEA. Inclusion criteria were: patients with asymptomatic carotid stenosis with a reduction of the carotid lumen diameter of more than 70% detected with Doppler ultrasound and diagnosed with one, two, or three vessel coronary artery disease with coronary stenosis more than 75% and hemodynamic significant stenosis of the left main artery. Exclusion criteria were patients with urgent and previous cardiac surgery and patients with myocardial infarction and stroke in the past one month. We monitored preoperative (ejection fraction, coronarography status), operative (number of grafts, on-pump or off-pump technique) and postoperative (extubation, unit care and hospital stay, bleeding and reoperation) details and complications (myocardial infarction, neurological events, inotropic agents and transfusion requiry, infection, arrhythmic complication, renal failure, mortality). Postoperative complications were observed in 18 (29.9%) patients. Two patients (2.3%) had postoperative stroke and one patient (1.2%) had transient ischemic attack (TIA). Previous stroke was a predictor for increased postoperative neurological events (P < .05). Intrahospital mortality was 8.1%. Simultaneous CEA and CABG were performed with low rates of stroke and TIA. Previous stroke was identified as a predictor for increased postoperative neurological complications.

Preparation of Patients for Elective Percutaneous Coronary Intervention: Management of Risk Factors as an Approach to Increase in Intervention Efficacy

Abstract The article is a topical literature review of the place of percutaneous coronary interventions in the structure of elective revascularisation procedures, preoperative preparation of patients with stable ischaemic heart disease before percutaneous coronary intervention, the prospects of the technique, taking into account the latest advances in intervention cardiology (intravascular methods for assessing the hemodynamic significance of stenosis, drug eluting stents). Modern data of the early and long-term results of percutaneous coronary intervention are presented, the predictable potentially modifiable risks of adverse events are described, and ways to correct them are discussed. The results of randomised studies comparing the effectiveness of different approaches for managing patients with stable coronary heart disease (medical therapy, percutaneous coronary intervention) are presented, and prospects for using new drugs to improve the early and late outcomes of endovascular revascularisation are discussed.

Impact of computed tomography (CT)-derived fractional flow reserve on reader confidence for interpretation of coronary CT angiography

PurposeTo assess the impact of computed tomography-derived fractional flow reserve (FFRCT) on reader confidence and reader time for interpretation of coronary computed tomography angiography (CCTA). Material and methodsThis IRB-approved, HIPAA-compliant, consent waivered, quality-improvement study included 50 patients (23 women, age 67 ± 12years, body mass index 28.7 ± 5.3 kg/m2). CCTA was acquired on 2nd and 3rd generation dual-source MDCT with use of beta-blockers and nitroglycerin, and FFRCT was calculated (HeartFlow,Redwood City,CA). Two readers with experience level COCATS2 (Core- Cardiology-Training-Symposium) and two with COCATS3 assessed severity of epicardial coronary artery disease (CAD) using CCTA alone and CCTA with FFRCT. Reader confidence for CAD and hemodynamically significant stenosis (HS) was rated on a 4-point Likert-scale (1=high, 2=good, 3=limited, 4=none) for the four major epicardial coronary artery (CA) vessels. Time to interpret was recorded. ResultsThe severity of CAD in the cohort population was CAD-RADS1 (Coronary-Artery-Disease Reporting-and-Data-System) n = 15, CAD-RADS2 n = 8, CAD-RADS3 n = 11, and CAD-RADS4A n = 16. Sixty-three CA in 30 patients had minimal FFRCT values ≤0.8. Reader confidence when using FFRCT increased for CAD and HS (p = 0.0001) with a reduction of “non-confident” patient reads (rank 3&4) by 27% and 75%, respectively. The change in confidence was not associated with CAD-RADS (p = 0.1) but correlated with reader experience (p < 0.001). The median time-to-read a CCTA study decreased by 5 min when FFRCT was available (p < 0.001). ConclusionInterpretation of CCTA in conjunction with FFRCT improved reader for assessment of severity of CAD and HS with reduction of “non-confident” reads and decreased the median time-to-interpretation of a CCTA.

Прогностическое значение оценки коронароангиографии, жесткости сосудистой стенки и диастолической дисфункции левого желудочка у больных ишемической болезнью сердца в сочетании с хронической болезнью почек

The importance of vascular wall rigidity, diastolic dysfunction of left ventricle in development of coronary heart disease in patients with chronic kidney disease is investigated. The possibility of coronary heart disease development in patients with pathology of kidneys, despite the absence of hemodynamic significant stenosis of coronary arteries according to the results of coronarography is established,the importance of detecting diastolic dysfunction as an early marker of developing heart failure in patients with combined pathology is shown. Studying diastolic dysfunction and vascular wall rigidity can help to define more presisely the degree of cardiovascular risk in these patients, and their monitoring in dynamics can be used as an additional objective criterion for evaluating therapy efficiency.

Early carotid endarterectomy in patients with symptomatic carotid stenosis in the acute period of ischemic stroke

To identify the optimal timing of CEA in patients with hemodynamic significant stenosis of carotid arteries in the acute period of ischemic stroke (IS). Five samples (n=30 911) based on the search results from January 2008 to April 2016 in Russian and English-language scientific databases were analyzed. The main endpoints of the studies in both groups (repeated stroke, death, cardiac complications, frequency of restenosis) were studied depending on the timing of operative intervention and preoperative selection criteria. Perioperative morbidity and mortality were analyzed within 30 days after disease onset. There are heterogeneous and contradictory information on the safety of CEA in patients with symptomatic carotid stenosis in acute period of IS. Fundamentally, a new individual approach is required to select best candidates for timed surgery after disease onset, taking into account the severity of the condition, risk factors, comorbidity and surgical techniques.

Evaluation of Hemodynamic Significance of Stenosis in Multiple Involvement of the Coronary Vessels by Mathematical Simulation.

We use a mathematical model of one-dimensional blood flow in a network of blood vessels for in silico evaluation of hemodynamic significance of stenoses in multivessel coronary disease. Two cases were addressed: two stenosed vessels with different diameters and with the same degree of occlusion and two consecutive stenoses in the same vessel. We show that two criteria for the evaluation of hemodynamic significance based on the degree of stenosis and based on fractional flow reserve can give contradictory indications for surgical intervention. We also show that fractional flow reserve computation originally proposed for a single stenosis should be modified in the case of multivessel stenotic disease.

Functional assessment of the stenotic carotid artery by CFD-based pressure gradient evaluation.

The functional assessment of a hemodynamic significant stenosis base on blood pressure variation has been applied for evaluation of the myocardial ischemic event. This functional assessment shows great potential for improving the accuracy of the classification of the severity of carotid stenosis. To explore the value of grading the stenosis using a pressure gradient (PG)-we had reconstructed patient-specific carotid geometries based on MRI images-computational fluid dynamics were performed to analyze the PG in their stenotic arteries. Doppler ultrasound image data and the corresponding MRI image data of 19 patients with carotid stenosis were collected. Based on these, 31 stenotic carotid arterial geometries were reconstructed. A combinatorial boundary condition method was implemented for steady-state computer fluid dynamics simulations. Anatomic parameters, including tortuosity (T), the angle of bifurcation, and the cross-sectional area of the remaining lumen, were collected to investigate the effect on the pressure distribution. The PG is highly correlated with the severe stenosis (r = 0.902), whereas generally, the T and the angle of the bifurcation negatively correlate to the pressure drop of the internal carotid artery stenosis. The calculation required <10 min/case, which made it prepared for the fast diagnosis of the severe stenosis. According to the results, we had proposed a potential threshold value for distinguishing severe stenosis from mild-moderate stenosis (PG = 0.88). In conclusion, the PG could serve as the additional factor for improving the accuracy of grading the severity of the stenosis.

One Session Bilateral Carotid Stenting – Experience from Slovakian Center

Abstract Objectives: Bilateral carotid artery stenting (BCAS) in one session is relatively rare procedure. However, clear recommendations still do not exist. The aim of our study was to analyze efficacy and safety of the BCAS performed by single operator in our center. Material and Methods: A retrospective analysis of 95 carotid angioplasty with stent implantation (CAS) patients performed in our center, totally 9 patients (8 males and 1 female, age 59-83, average 69) was identified where simultaneous BCAS was performed. All patients had bilateral hemodynamic significant stenosis (≥ 70 %), and all patients had symptomatic stenosis. Results: Only 1 patient was without any complication. The most frequent complications were arterial hypotension. However, duration of stay on the Intensive Care Unit, or hospitalisation was not prolonged. From serious complications we noticed one case of periprocedural filter occlusion and one patient died 30 days after procedure. No other serious complications were in the BCAS group noticed. Conclusion: Because of limited data it is not possible to make any clear conclusions or recommendations from the results of our study. Our data show that probably BCAS appears to be safe and effective way in the treatment of bilateral carotid artery stenosis in high-risk population.

Association of coronary plaque burden with fractional flow reserve: should we keep attempting to derive physiology from anatomy?

Coronary computed tomography angiography (CTA) has been used increasingly for the diagnosis of coronary artery disease over the past decade. Compared to invasive coronary angiography (ICA), coronary CTA has the ability to visualize and quantify atherosclerotic plaque both calcified and non-calcified. Traditional measures of evaluating a coronary stenosis such as diameter stenosis, area stenosis, minimal lumen diameter and minimal luminal area are limited in their ability to predict its functional significance especially when diameter stenosis ranges between 30-69% (intermediate range). Measurement of invasive fractional flow reserve (FFR) is considered the gold standard for assessment of the hemodynamic significance of a stenosis. The current study by Nakazato et al. evaluates the performance of an emerging coronary CTA-derived anatomical measure "percent aggregate plaque volume" to improve the detection of hemodynamic significant stenosis as compared with invasive FFR.

Imaging and endovascular management in allograft renal artery stenosis: Case report

Transplant renal artery stenosis (TRAS) is a relatively frequent, potentially curable cause of refractory hypertension and allograft dysfunction and usually becomes apparent between 2 months and 2 years after renal transplantation. Depending on the hemodynamic significance of stenosis it can be treated conservatively or by revascularization. Here we describe a case of TRAS which was treated successfully with angioplasty with a brief review of its etiology, natural history, diagnosis and therapy.

The impact of vascular risk factors multiplicity on severity of carotid atherosclerosis—A retrospective analysis of 1969 Egyptian subjects

Background and Purpose: Carotid atherosclerosis has been recognized as a major cause of stroke. The cur-rent study aimed to describe the effect of multiplicity rather than the type of vascular risk factors on severity of carotid atherosclerosis among a large sample of Egyptian population. Methods: We analyzed the data of 1969 Egyptian subjects, who proved to have extra cranial carotid atherosclerotic disease by duplex scanning at the vascular laboratories of Cairo Uni-versity Hospitals. Demographic, clinical data and causes of referral were recorded and correlated with ultrasound findings. Atherosclerotic indices, namely IMT, plaque number and percentage of stenosis were used for evaluation of severity of carotid atherosclerosis. Furthermore, subjects were classified according to multiplicity of major atherosclerotic risk factors and multivariate regression analysis was performed to detect independent predictors of significant carotid disease. Results: Out of 1969 subjects with proved signs of extracranial carotid atherosclerosis by duplex ultrasonographic scan, 225 (11.4%) showed hemody-namic significant stenosis (≥50%). Multiplicity of risk factors beyond the age of 50 years was the strongest predictor of significant stenosis. Conclusion: Age more than 50 years and multiplicity rather than the type of risk factors were the strongest predictors of significant carotid atherosclerotic disease (CAD).

Coronary Flow Velocity Reserve in the Three Main Coronary Arteries Assessed with Transthoracic Doppler: A Comparative Study with Quantitative Coronary Angiography

The purpose of this study was to evaluate the potential of combined use of transthoracic Doppler echocardiographic coronary flow velocity reserve (CFVR) measurements and findings of retrograde coronary flow in the three main coronary arteries for the assessment of borderline (angiographic diameter stenosis, 50%-75%) and high-grade (angiographic diameter stenosis, 76%-100%) coronary artery stenoses. A total of 108 patients scheduled for coronary angiography because of chest pain or acute coronary syndromes were studied. CFVR was measured during adenosine-induced hyperemia in the mid to distal segments of the left anterior descending coronary artery, the marginal branches of the left circumflex coronary artery, and the posterior descending coronary artery, with peak CFVR (pCFVR) <2.0 implying hemodynamic significant stenosis. CFVR results were compared with results from quantitative coronary angiography, with stenosis severity in the left main and three major coronary arteries divided into three groups: (1) diameter stenosis 0% to 49%, (2) diameter stenosis 50% to 75%, and (3) diameter stenosis 76% to 100%. In patients with antegrade flow in the relevant coronary artery segment, CFVR was successfully measured in the mid to distal left anterior descending artery, the marginal branches of the left circumflex artery, and the posterior descending artery in 97%, 63%, and 75% of patients, respectively. CFVR was significantly different among the stenosis groups, with pCFVR of 2.79 ± 0.77 in group 1, 2.01 ± 0.72 in group 2, and 1.50 ± 0.69 in group 3 (P < .001 among groups). Angiography confirmed retrograde flow in seven of the nine arteries found by transthoracic echocardiography. Findings of pCFVR <2.0 or retrograde coronary artery flow correctly identified 42 of 49 patients with stenoses in group 3, with sensitivity, specificity, and positive and negative predictive values of 86%, 70%, 70%, and 85%, respectively. In group 2, pCFVR values were widely distributed above or below the defined pCFVR cutoff value. CFVR measurement in the mid to distal left anterior descending artery was feasible in almost all patients, and in the marginal branches of the left circumflex artery and the posterior descending artery in two thirds and three quarters of patients, respectively. Use of the combined echocardiographic criteria had high precision for diagnosing severe coronary stenoses (diameter stenosis, 76%-100%). The functional significance of angiographically borderline stenoses (diameter stenosis, 50%-75%) may be further differentiated by the use of CFVR measurements.

Correlation between morphologic carotid plaque findings based on color-Doppler and CT multidetector angiography with intraopertive findings in carotid artery stenosis

Vast majority of patients with corotid arthery sclerosis do not have transitory ischemic attacs (TIA) as working to the persistent silent disease, but stroke is the first sign. Precise and early diagnosis of the carotid artery disease and plaques are very important. The aim of this study was to determine how the composition/identity of diagnostic methods, color-Doppler, ultrasonography (US) CT-multidetector angio (MDCTA) scan and intraoperative (IO) findings, as well as the morphology of plaques in patients with haemodynamic significant stenosis of the internal carotid artery. Carotid plaques were observed by two diagnostic methods, US and MDCTA, and these findings were correlated with the IO findings. In 62 patients both carotid artheries were examined and 83 plaques were observed. There were 68 surgical interventions. The structure of plaques was divided into four types: lipid, fibrous, fibrocalcified and calcified plaque. US showed: lipid plaques 10.8%; fibrous 1.2%; fibrocalcified 44.6% and calcified 43.4%, and the MDCTA lipid plaques 8.4%; fibrocalcified 48.2% and calcified 43.4%. Intraoperative findings were: lipid plaques 10.3%; fibrocalcified 41.2% and calcified 48.5%. A statistically highly significant agreement between the US and MDCTA in the diagnosis of plaque morphology was obtained (Cramer's V = 0.919, p < 0.01; Lambda = 0.921, p < 0.01) and also statistically significant agreement between US and IO findings (Cramer's V = 0.831,p < 0.01; Lambda = 0.859, p < 0.01). A statistically highly significant agreement between MDCTA and IO findings in plaque morphology was found, as well (Cramer's V = 0.815, p < 0.01; Lambda = 0.829, p < 0.01). There is statistically highly significant correlation between US and MDCTA diagnostic methods in the evaluation of plaque morphology in surgically significant stenosis of internal carotid artery as well as their agreement with the intraoperative finding.

Improvement of fractional flow reserve and collateral flow by treatment with external counterpulsation (Art.Net.‐2 Trial)

Arteriogenesis (collateral artery growth) is nature's most efficient rescue mechanism to overcome the fatal consequences of arterial occlusion or stenosis. The goal of this trial was to investigate the effect of external counterpulsation (ECP) on coronary collateral artery growth. A total of 23 patients (age 61 +/- 2.5 years) with stable coronary artery disease and at least one haemodynamic significant stenosis eligible for percutaneous coronary intervention were prospectively recruited into the two study groups in a 2 : 1 manner (ECP : control). One group (ECP group, n = 16) underwent 35 1-h sessions of ECP in 7 weeks. In the control group (n = 7), the natural course of collateral circulation over 7 weeks was evaluated. All patients underwent a cardiac catheterization at baseline and after 7 weeks, with invasive measurements of the pressure-derived collateral flow index (CFIp, primary endpoint) and fractional flow reserve (FFR). In the ECP group, the CFIp (from 0.08 +/- 0.01 to 0.15 +/- 0.02; P < 0.001) and FFR (from 0.68 +/- 0.03 to 0.79 +/- 0.03; P = 0.001) improved significantly, while in the control group no change was observed. Only the ECP group showed a reduction of the Canadian Cardiovascular Society (CCS, P = 0.008) and New York Heart Association (NYHA, P < 0.001) classification. In this study, we provide direct functional evidence for the stimulation of coronary arteriogenesis via ECP in patients with stable coronary artery disease. These data might open a novel noninvasive and preventive treatment avenue for patients with non-acute vascular stenotic disease.