Coronary Artery Territory Research Articles

Do chronic total occlusive lesions affect patency of coronary bypass grafts to the right coronary artery?

To evaluate the impact of chronic total occlusion (CTO) lesions on the patency of bypass grafts to the right coronary artery territory. Two hundred patients undergoing primary isolated coronary artery bypass grafting with revascularization to the right coronary artery territory between April 2015 and July 2022 were retrospectively analyzed. Study patients were divided into two groups according to their right coronary artery lesion: patients with CTO lesions (n = 76) and those without CTO lesions (n = 124). Graft flow of the right coronary artery territory was evaluated by intraoperative transit time flow measurement and patency of the bypass graft was evaluated by multidetector row computed tomography. A total of 200 patients (76 patients with CTO and 124 patients without CTO) were included in this study. Intraoperative transit time flow measurement demonstrated that there was no significant difference in the median mean graft flow (30 ml/min vs. 25 ml/min; p = 0.114), pulsatility index (2.1 vs. 2.4; p = 0.079), and diastolic filling rate (65% vs. 64%; p = 0.844) between patients with CTO and those without CTO. Postoperative multidetector row computed tomography demonstrated that the patency of bypass grafts to the right coronary artery territory was similar between the groups (94.7% in patients with CTO vs. 96.0% in those without CTO; p = 0.733). In patients with CTO, the patency of bypass graft tended to be worse in subgroup with rich collateral blood flow (Rentrop grade 3). Chronic total occlusion lesions do not affect the patency of bypass grafts to the right coronary artery territory.

No-Touch Saphenous Vein as Y-Composite vs Aortocoronary Graft: Early Outcome Analysis

BackgroundA randomized controlled trial was designed to compare 1-year morphologic changes of the no-touch saphenous vein (SV) as a Y-composite graft (composite group) vs an aortocoronary graft (aorta group) in coronary artery bypass grafting. This study evaluated early clinical and angiographic outcomes as a preliminary analysis. MethodsThe primary end point of the trial was the intima-media thickness measured by intravascular ultrasound at 1-year angiographic follow-up. Patients were screened to enroll 25 patients in each group based on a superiority design. Early postoperative clinical and angiographic outcomes were compared between the 2 groups. ResultsThe numbers of distal anastomoses per SV graft were 2.7 ± 1.1 and 2.6 ± 0.8 in the composite and aorta groups, respectively. There was no operative death, and postoperative complications in the 2 groups did not significantly differ. All patients underwent early postoperative graft angiography at a median of 1 (interquartile range, 1-1) day after operation. Early angiographic patency rates were 98.9% (93/94 anastomoses) and 100% (90/90 anastomoses) in the composite and aorta groups, respectively. There was no distal anastomosis showing competitive flow in the aorta group, whereas 3 anastomoses with competitive flow were found in the composite group. All 3 anastomoses with competitive flow were SV grafts that were anastomosed to the right coronary artery territory with moderate stenosis. ConclusionsEarly clinical outcomes and angiographic graft patency rates were not significantly different with use of no-touch SV as a Y-composite graft or an aortocoronary graft.

Territorial Post-Revascularization Remodeling of Chronic Coronary Syndromes: Cardiac Magnetic Resonance Feature Tracking Study.

MRI feature-tracking (MRI-FT) can accurately assess ventricular myocardial deformation and regional function and may be a better predictor of mortality than ejection fraction and infarct extension. However, role of MRI-FT in assessing coronary revascularization is unclear. To assess coronary revascularization effect on territorial left ventricle (LV) function of chronic coronary syndrome (CCS) patients by MRI-FT. Prospective. 50 CCS patients (age: 62.22 ± 8.70 years) scheduled for elective percutaneous coronary intervention (PCI), and 30 healthy controls (age: 35.33 ± 11.57 years). 1.5T with balanced steady-state free precession cine sequence. Global and segmental peak systolic longitudinal, circumferential, and radial myocardial strains were quantified in both patient and healthy control groups by an experienced operator using dedicated software. Patients were studied both pre-PCI and 6-month post-PCI and LV territorial myocardial strain values were calculated by averaging the segmental values of each revascularized territory. Student's t-test, paired t-test, Mann Whitney test, and Wilcoxon signed ranks test. Significance was judged at the 5% level. Territorial longitudinal strain showed significant 6-month post-PCI improvement in the left anterior descending (LAD) and right coronary artery (RCA) territories, but there was not in the left circumflex (LCX) territory (LAD: mean - 11.41% ± 3.45% pre, -13.01% ± 3.53% post; RCA: mean - 11.11% ± 2.65% pre, -13.25% ± 2.81% post; and LCX: mean - 15.43% ± 3.97% pre, -16.17% ± 4.38% post, P = 0.215). Territorial circumferential strain showed significant post-PCI improvement in all revascularized territories (LAD: mean - 13.73% ± 6.56% pre, -16.98% ± 6.01% post; LCX: mean - 13.23% ± 4.23% pre, -16.34% ± 3.45% post; and RCA: mean - 11.24% ± 3.36% pre, -13.80% ± 3.51% post). Territorial radial strain showed no significant post-PCI improvement (LAD: mean 22.73% ± 12.38% pre, 21.79% ± 11.55% post, P = 0.541; LCX: mean 27.73% ± 7.95% pre, 29.0% ± 7.25% post, P = 0.264; and RCA: mean 36.68% ± 11.10% pre, 31.75% ± 10.95% post, P = 0.208). Territorial LV systolic function was significantly improved by coronary revascularization in CCS patients. 1 TECHNICAL EFFICACY: Stage 4.

Changes in myocardial blood flow in a canine model of left sided breast cancer radiotherapy.

Left-sided breast cancer patients receiving adjuvant radiotherapy are at risk for coronary artery disease, and/or radiation mediated effects on the microvasculature. Previously our laboratory demonstrated in canines with hybrid 18FDG/PET a progressive global inflammatory response during the initial one year following treatment. In this study, the objective is to evaluate corresponding changes in perfusion, in the same cohort, where resting myocardial blood flow (MBF) was quantitatively measured. In five canines, Ammonia PET (13NH3) derived MBF was measured at baseline, 1-week, 1, 3, 6 and 12-months after cardiac external beam irradiation. MBF measurements were correlated with concurrent 18FDG uptake. Simultaneously MBF was measured using the dual bolus MRI method. MBF was significantly increased at all time points, in comparison to baseline, except at 3-months. This was seen globally throughout the entire myocardium independent of the coronary artery territories. MBF showed a modest significant correlation with 18FDG activity for the entire myocardium (r = 0.51, p = 0.005) including the LAD (r = 0.49, p = 0.008) and LCX (r = 0.47, p = 0.013) coronary artery territories. In this canine model of radiotherapy for left-sided breast cancer, resting MBF increases as early as 1-week and persists for up to one year except at 3-months. This pattern is similar to that of 18FDG uptake. A possible interpretation is that the increase in resting MBF is a response to myocardial inflammation.

Clinical and hemodynamic characteristics of patients with intermediate coronary lesions selected for elective percutaneous coronary intervention

The aim – to identify clinical, angiographic and hemodynamic factors, having impact upon the decision on percutaneous coronary intervention (PCI) in stable coronary artery disease (SCAD) patients with intermediate subepicardial coronary lesions, in clinical settings. Materials and methods. The cross-sectional single-center study analyzed clinical and instrumental data from 123 SCAD patients (mean age 62 ± 9 years; 90 (73.2 %) males) and intermediate (50–90 %) stenotic subepicardial coronary lesions (by invasive coronary angiography [ICA]). The enrolled sample included 74 (60.2 %) patients with an assessment of ICA-derived fractional flow reserve (FFR). The studied parameters were analyzed in the groups of decision not to perform (PCI(–); n = 30 [24.4 %]) and to perform PCI (PCI(+); n = 93 [75.6 %]). Results. The positive decision on PCI was more frequent in patients with stable angina ІII and ІI CCS class, as compared to those without angina (93 %, 79 % і 46 %, respectively; рtrend < 0.001). PCI was considered to be appropriate in all patients with FFR < 0.8 (46 of 74 (62 %) cases). The more advanced hemodynamic compromise of coronary lesions was associated with the higher maximum degree of coronary artery stenosis. Multivariable logistic regression analysis revealed a more pronounced coronary stenosis (at least, in one subepicardial coronary artery territory) was independently associated with the PCI(+) decision (stenosis 80–90 % vs. 70–79 %; 70–79 % vs. 60–69 %; 60–69 % vs. 50–59 %: odds ratio 26 (95 % confidence interval 8–87); р < 0.001). Conclusions. A degree of coronary artery stenosis was a key factor impacting upon a positive decision on PCI in SCAD patients with intermediate (50–90 %) coronary lesions. There is a need for the broader implementation of non-invasive diagnostic tests and the tools for a quantitative assessment of myocardial ischemia in patients with intermediate pretest probability of coronary stenosis, including those with previous PCI.

Positron emission tomography rubidium-82 myocardial perfusion imaging in diagnosing uncommon paediatric acute coronary syndrome: a case report

BackgroundAcute coronary syndrome (ACS) is uncommon among the paediatric population with no guideline in the management in this age group up to this date. This case report aims to introduce the Positron Emission Tomography Rubidium-82 (PET Rb-82 MPI) as one of the non-invasive diagnostic tools in paediatric acute coronary syndrome.Case presentationPatient is an 11-year-old boy with underlying Nephrotic syndrome who was referred to our hospital with the chief complaint of chest pain. This was associated with raised cardiac enzyme and S–T depression on the posterior leads of electrocardiogram. On his arrival, we noted raised lipid profile as well as proteinuria and hypoalbuminaemia. He had frequent relapse of Nephrotic syndrome with the latest episode was three months ago. He has a strong family history of ischaemic heart disease whom his father had an episode of myocardial infarction at the age of 40 as well as a strong family history of hypercholesterolaemia. His father and paternal uncle were diagnosed with hypercholesterolaemia at their early age. He was arranged for Coronary Computed Tomography Angiography which subsequently followed by PET Rb-82 MPI. The PET Rb-82 MPI demonstrated a large area of stress induced ischaemia in the left anterior descending, left circumflex and right coronary artery territories. The left ventricular size is normal with good systolic function and normal wall motion. Global coronary flow reserve was still preserved at 2.07. Following the multi-disciplinary meeting, diagnosis of ACS was established. Patient was treated with dual anti-platelets, and he was then arranged for coronary angiography. The coronary angiography showed complete occlusion of the left circumflex artery from the proximal segment. There was a mild disease at mid segment of the diagonal artery with myocardial bridging. There was also a moderate disease from proximal segment of the dominant right coronary artery. Paclitaxel drug coated balloons were inserted into the diagonal and left circumflex arteries.ConclusionsThis rare case report on paediatric ACS highlights the diagnostic value of PET Rb-82 MPI as one of the non-invasive imaging tools in diagnosing paediatric acute coronary syndrome.

Integrating subvolume dose and myocardial perfusion imaging parameters to assess the impact of radiation therapy on heart function in breast cancer patients: A comparative analysis between left- and right-sided breast cancer.

This study aimed to utilize an innovative method of integrating the 20 subvolume dose of left ventricle and the Tl-201 single photon emission computed tomography (SPECT) with myocardial perfusion imaging (MPI) parameters in patients with left- and right-sided breast cancer after radiation therapy. Female patients with breast cancer underwent SPECT MPI before commencing radiotherapy and 12 months later were enrolled from January 2014 to December 2018. The images of CT simulation and SPECT MPI were integrated into the treatment planning system. The differences of doses and parameters of MPI in all cardiac subvolumes between left- and right-sided breast cancer patients were analyzed. Patients with left-sided breast cancer (n = 61) received a higher radiation dose to the heart, left ventricular, and its territories and subvolumes, compared to patients with right-sided breast cancer (n = 19). The 20-segment analysis also showed statistically significant disparities in the average radiation doses received by the two groups. In different coronary artery territories, the end-diastolic perfusion and end-systolic perfusion showed a decrease in both sides, with no significant differences. However, the wall motion and wall thickening showed a significant decline in subregions within the left- and right-sided coronary artery territories. This study demonstrates an innovative integrated method combining the left ventricular 20 regional doses with SPECT MPI which shows that left-sided breast cancer patients receive a higher subvolume dose than right-sided breast cancer patients. Further research is needed to confirm the potential impact on heart function after radiotherapy on both sides.

Assessing the Effect of the Coronary Artery and Myocardial Territory Size on Fractional Flow Reserve and Instantaneous Wave-Free Ratio

Assessing the Effect of the Coronary Artery and Myocardial Territory Size on Fractional Flow Reserve and Instantaneous Wave-Free Ratio

Quantification of myocardial blood flow using stress cardiac magnetic resonance for the detection of coronary artery disease

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): GE Healthcare. Background Myocardial blood flow (MBF) analysis using stress cardiac magnetic resonance (CMR) has been shown to detect obstructive coronary artery disease (CAD); however, evaluation of its diagnostic performance has primarily been limited to single-center studies. AQUA-MBF (Assessment of QUAntitative MBF using stress CMR) is an international study with the goal of assessing the diagnostic performance of stress MBF for the detection of CAD. In this study, we aim to determine how stress MBF assessment compared against visual analysis (VA) of stress CMR images for the detection of CAD. Methods. 144 individuals (89 (62%) men, age 62±16 years, 97 (68%) hypertension, 54 (38%) diabetes, 92 (64%) hyperlipidemia) from 9 centers who underwent dual sequence stress CMR (1.5T or 3.0T GE Healthcare) and also had either a coronary computed tomography angiography (CTA, n=31), invasive coronary angiogram (ICA, n=95), or low pre-test probability for CAD (n=18) were included. CAD was defined as the presence of: (1) a stenosis ≥50% in the left main coronary artery or ≥70% in the 1 major vessel based on ICA or CTA or (2) an invasive fractional flow reserve (FFR) ≤ 0.8. Absence of obstructive coronary disease (NOCAD) was defined as a no history of myocardial infarction and stenosis <50% by ICA or CTA, 50–70% stenosis with FFR>0.8, or a young individual with no cardiac risk factors. Myocardial perfusion imaging was performed during first pass perfusion of a gadolinium-based contrast agent following the administration of adenosine or regadenoson with a low-resolution image acquired to assess the arterial input function and 2–3 short axis slices acquired to assess myocardial perfusion. VA was performed by 2 experienced cardiologists who assigned a grade of 1–5 based on the probability a study was abnormal. Stress MBF values were determined for each of the 16 myocardial segments using Fermi deconvolution (CircleCVI). The global stress MBF was calculated as the average value of two segments with the lowest values from each of the three coronary artery territories. Unpaired t-test was used to compare stress MBF values between CAD vs NOCAD. Receiver-operating characteristics curves were used to determine diagnostic performance. Results. 60 patients had CAD (20: 1-vessel, 26: 2-vessel, and 14: 3-vessel) (Figure 1A) while 84 had NOCAD (Figure 1B). The global stress MBF in CAD was lower than in NOCAD (1.63±0.52ml/g/min vs 2.41±0.68ml/g/min, p<0.0001) (Figure 2A). Stress MBF had a higher AUC than VA (reader 1 – 0.83 vs 0.73, p = 0.07: reader 2–0.83 vs 0.71, p = 0.02). The optimal stress MBF cut-off value for detecting CAD was 2.05ml/g/min (Figure 2B). Conclusions. In this multicenter study, we show that global stress MBF reported as a single value can identify patients with CAD at least as accurately as VA performed by physicians experienced in the interpretation of stress CMR images.

Assessment of the left ventricular longitudinal deformation failed to detect early changes after the second-stage percutaneous coronary intervention in patients with the acute coronary syndrome

Abstract Funding Acknowledgements Type of funding sources: None. Background Primary intervention in acute coronary syndrome (ACS) is often followed by the second-stage procedure when other atherosclerotic lesions are present. However, there is no data regarding the early effects of such a strategy on left ventricular function. Speckle-tracking echocardiography has been proven a sensitive method in assessing myocardial function. Purpose The study aimed to assess the early results of the second stage of percutaneous coronary intervention (PCI) in patients with ACS. Methods The study group consisted of 61 patients aged from 47 to 92 (mean age 66,3± 9,8) years, 21 women (34,4%) and 40 men (65,6%) who had ACS. Primary treatment involved culprit-lesion only. All pts were optimally treated regarding ischemic heart disease. The second-stage PCI was performed up to four months after ACS. Patients underwent transthoracic echocardiography 48 hours before and after the second-stage PCI. Using automated functional imaging (AFI), we analyzed the global longitudinal strain (GLS) of the left ventricle, GLS in the four-chamber view (GLS-4CH), the two-chamber view (GLS-2CH), and the three-chamber view (GLS-3CH). We also assessed the mean of the peak longitudinal strain of the myocardial segments according to the standard assignment to coronary artery territories, i.e. left anterior descending (LAD), right coronary artery (RCA) and circumflex coronary artery (LCX). Results The following second-stage PCI were performed in the study group: 33 procedures regarding the left anterior descending artery, 15 procedures regarding the left circumflex artery and 13 procedures regarding the right coronary artery. The mean value of the GLS of the left ventricle before the second-stage PCI was slightly reduced compared to the currently established norm (GLS= −16.7%). The second-stage PCI did not result in early changes in the GLS. We also did not observe any significant changes in the mean peak longitudinal strain according to the coronary artery territories (Table 1). Conclusions Despite the proven sensitivity of the deformation imaging technique in assessing left ventricular function, the present work does not show an early effect of the percutaneous coronary intervention on either the global longitudinal strain of the left ventricle or the longitudinal strain of the segments allocated to each coronary arterial territory.

Potential Role of Somatostatin Receptor Scintigraphy for In Vivo Imaging of Vulnerable Atherosclerotic Plaques and Its Association with Myocardial Perfusion Imaging Finding: A Preliminary Study.

This study was conducted to detect atherosclerotic plaques with somatostatin receptor scintigraphy (SRS) using Tc-99m-octreotide that binds to somatostatin receptor-2. Of the 783 patients referred for myocardial perfusion imaging (MPI), 52 underwent additional chest single-photon emission computed tomography (SPECT) with Tc-99m-octreotide and participated in this study. In addition, 43 patients who underwent Tc-99m-octreotide scan for neuroendocrine tumor (NET) also received cardiac SPECT. Angiography was performed within 1 month after SRS for 19 patients who showed intensive uptake in SRS and had cardiac risk factors. Of 52 patients who underwent MPI and SRS, 15 showed intensive cardiac uptake in SRS. Moreover, of 43 patients who were referred for NET, 4 patients had marked cardiac uptake in SRS in the heart. Nineteen patients including 12 women and 7 men aged 28 to 84 (58±8.04) years underwent coronary angiography. SRS and angiography in the left anterior descending territory were concordant in 15/19 (79%) patients, whereas only 7/15 (46%) cases had concordant MPI and angiography results. In the right coronary artery territory, SRS and angiography were concordant in 16/19 (84%) cases, while MPI and angiography were concordant in 11/15 (73%) cases. In the left circumflex artery territory, SRS and angiography were concordant in 15/19 (79%) cases, whereas MPI and angiography were concordant in 6/15 (40%) cases. In the remaining 76 patients who did not undergo coronary angiography based on cardiovascular profile and SRS, no cardiac events occurred in a follow-up of 2-11 months (7.52±2.71). Tc-99m-octreotide uptake was more concordant with coronary plaques relative to MPI findings, suggesting a potential role for Tc-99m-octreotide in the evaluation of atherosclerosis.

A changing heart in tako-tsubo syndrome.

A 63-year-old female presented with acute chest pain and ECG showing T wave inversion in the anterior and inferior leads. Troponin T (TnT) was significantly elevated (peak 1378 ng/L; normal <14 ng/L), as was NT-proBNP (3091 ng/L; normal <400 ng/L). Invasive angiography showed unobstructed coronary arteries with mid-ventricular ballooning and hypokinesia on ventriculography (see Supplementary data online, Video S1) and echocardiography (see Supplementary data online, Video S2), suggesting a mid-ventricular tako-tsubo syndrome (TTS). Cardiac magnetic resonance (CMR) was booked but the patient was unable to attend. Focussed history using the InterTAK diagnostic score assessment revealed no emotional or physical triggers. The patient re-presented six months later with similar symptoms and elevated TnT. Inpatient echocardiography showed a reverse TTS pattern (see Supplementary data online, Video S3) and CMR at 1.5T showed basal hypokinesia with matching elevated native T1 (1220 ms; normal 950–1100 ms) and T2 (69 ms; normal <48 ms) (Panels A–B). Quantitative perfusion maps following adenosine stress perfusion to investigate microvascular disease showed basal to mid circumferential hypoperfusion with normal apical myocardial blood flow, not suggestive of specific coronary artery territory ischaemia (Panel D) and no late gadolinium enhancement (LGE) (Panel C), confirming a reverse TTS. The patient further presented two months later with chest pain and TnT elevation. Repeat inpatient CMR on this occasion showed a classic TTS pattern with apical hypokinesia and elevated T1 and T2 (1261 ms and 81 ms, respectively) at the mid to apical segments with no LGE (Panels E–G). The case was further explored but no triggers, including neurological or psychiatric abnormalities were found. Recurrent TTS with different phenotypes has previously been described but is rare, especially without a trigger. Our case illustrates the utility of multimodality imaging in the investigation of TTS; in particular, multiparametric tissue mapping by CMR. Furthermore, the novel quantitative perfusion maps characterising myocardial blood flow added diagnostic utility.

PET/MRI Assessment of Acute Cardiac Inflammation 1 Month After Left-Sided Breast Cancer Radiation Therapy.

Our purpose was to investigate the utility of 18F-FDG PET/MRI and serial blood work to detect early inflammatory responses and cardiac functionality changes at 1 mo after radiation therapy (RT) in patients with left-sided breast cancer. Methods: Fifteen left-sided breast cancer patients who enrolled in the RICT-BREAST study underwent cardiac PET/MRI at baseline and 1 mo after standard RT. Eleven patients received deep-inspiration breath-hold RT, whereas the others received free-breathing RT. A list-mode 18F-FDG PET scan with glucose suppression was acquired. Myocardial inflammation was quantified by the change in 18F-FDG SUVmean (based on body weight) and analyzed on the basis of the myocardial tissue associated with the left anterior descending, left circumflex, or right coronary artery territories. MRI assessments, including left ventricular functional and extracellular volumes (ECVs), were extracted from T1 (before and during a constant infusion of gadolinium) and cine images, respectively, acquired simultaneously during the PET acquisition. Cardiac injury and inflammation biomarker measurements of high-sensitivity troponin T, high-sensitivity C-reactive protein, and erythrocyte sedimentation rate were measured at the 1-mo follow-up and compared with preirradiation values. Results: At the 1-mo follow-up, a significant increase (10%) in myocardial SUVmean in left anterior descending segments (P = 0.04) and ECVs in slices at the apex (6%) and base (5%) was detected (P ≤ 0.02). Further, a significant reduction in left ventricular stroke volume (-7%) was seen (P < 0.02). No significant changes in any circulating biomarkers were seen at follow-up. Conclusion: Myocardial 18F-FDG uptake and functional MRI, including stroke volume and ECVs, were sensitive to changes at 1 mo after breast cancer RT, with findings suggesting an acute cardiac inflammatory response to RT.

Two-Dimensional Speckle-Tracking Echocardiography to Monitor Left Ventricular Function After Percutaneous Coronary Intervention

Background: Conventional 2 D Doppler echocardiographic parameters are inadequate for evaluation and monitoring Left ventricle systolic function recovery of patients with ischemic heart disease (IHD) treated by Percutaneous coronary intervention (PCI). Hence, New strain imaging parameters are studied by using 2 D speckle Tracking Echocardiography. The aim is to compare the conventional echocardiographic parameters (Left ventricle ejection fraction, Wall motion score index, regional wall motion score) with speckle tracking echocardiographic parameters (Global longitudinal strain, Regional longitudinal strain) in patients with ischemic heart disease undergo Percutaneous Coronary Intervention (PCI).Method and patient: A prospective Interventional Hospital Based study enrolled 50 patients who had ischemic heart disease (IHD), Percutaneous coronary intervention (PCI) was done for them at IbN Al-Bittar Cardiac Surgery Center from October 2014 to April 2015. Both conventional echocardiographic parameters (Left ventricle ejection fraction, Wall motion score index, regional wall motion score according to coronary artery territory) and Speckle tracking echocardiographic parameters (Global longitudinal strain, Regional longitudinal strain according to coronary artery territory) done for them pre PCI, one day post PCI, and one month post PCI.Result: Regarding conventional echocardiographic parameters: Global LVEF pre PCI 52.34±90% , one month post PCI was (54.00±6.9), there was no significant difference statistically (P value 0.79), also Wall motion score index ,Regional wall motion score according to coronary artery territory were (1.22±0.25,1.44±1.52) respectively, one month post PCI were (1.98±0.26,1.40±0.58) respectively where there's no significant differences statistically (P value 0.25,0.22) respectively.Regarding speckle tracking parameters :Global Longitudinal strain for all patients pre PCI was (-14.30±3.54%) ,one day post PCI was (-14.78±3.81%) ;there was no significant differences (p value 0.77).After one month Global Longitudinal Strain was (-16.38±4.15%) where this consider highly significant differences (p value 0.001).Regional Longitudinal Strain according to the coronary artery territory pre PCI was (-14.49±4.47%),post one day post PCI was (-15.08±4.92%) where there's no significant differences (p value 0.10), while one month post PCI was (-17.70±5.27%),this was highly significant different statistically (0.001).Only in STEMI patients there was significant difference one day post PCI(P value 0.041 for Global LS,0.016 for Regional LS).Conclusions: In all IHD groups (STEMI, NSTEMI ∕UA, chronic stable angina) Speckle Tracking Echocardiographic parameters (Global Longitudinal Strain and Regional longitudinal strain) more reliable and effective than conventional echocardiographic parameters (Global LWEF,WMSI, RWMS) for monitoring improvement in LV systolic function post Percutaneous coronary intervention.

Automated identification of myocardial perfusion defects in dynamic cardiac computed tomography using deep learning

PurposeThe purpose of this study was to develop and evaluate deep convolutional neural network (CNN) models for quantifying myocardial blood flow (MBF) as well as for identifying myocardial perfusion defects in dynamic cardiac computed tomography (CT) images. MethodsAdenosine stress cardiac CT perfusion data acquired from 156 patients having or being suspected with coronary artery disease were considered for model development and validation. U-net-based deep CNN models were developed to segment the aorta and myocardium and to localize anatomical landmarks. Color-coded MBF maps were obtained in short-axis slices from the apex to the base level and were used to train a deep CNN classifier. Three binary classification models were built for the detection of perfusion defect in the left anterior descending artery (LAD), the right coronary artery (RCA), and the left circumflex artery (LCX) territories. ResultsMean Dice scores were 0.94 (±0.07) and 0.86 (±0.06) for the aorta and myocardial deep learning-based segmentations, respectively. With the localization U-net, mean distance errors were 3.5 (±3.5) mm and 3.8 (±2.4) mm for the basal and apical center points, respectively. The classification models identified perfusion defects with the accuracy of mean area under the receiver operating curve (AUROC) values of 0.959 (±0.023) for LAD, 0.949 (±0.016) for RCA, and 0.957 (±0.021) for LCX. ConclusionThe presented method has the potential to fully automate the quantification of MBF and subsequently identify the main coronary artery territories with myocardial perfusion defects in dynamic cardiac CT perfusion.

Transcoronary electrophysiological parameters in patients undergoing elective and acute coronary intervention.

Percutaneous coronary intervention is performed routinely in the management of myocardial infarction with obstructive coronary disease, but intervention to arteries supplying nonviable myocardium may be harmful. It is important therefore to establish myocardial viability, and there is an unmet need in current clinical practice for real time viability assessment to aid in decision making. Transcoronary pacing to assess myocardial electrophysiological parameters may be a novel viability assessment technique which could be used in this regard. Coronary intervention was carried out according to standard departmental procedure with standard equipment. An exchange length coronary guidewire was passed into both target and reference coronary vessels and an over-the-wire balloon or microcatheter was used to insulate the guidewire and allow electrophysiological parameters to be assessed. Readings were obtained from all major epicardial vessels and substantial branches. At each position, an intracoronary electrocardiogram was recorded, and R wave amplitude was measured. Transcoronary pacing was then performed to establish threshold and impedance for each myocardial segment. A viability cardiac MRI scan was performed for each patient. A standard segmental model was used to determine viability in each segment using an 'infarct score' based on degree of late gadolinium enhancement. Studies were reported blinded to the electrical parameters obtained from the coronary guidewire. The primary outcome was the relationship between pacing threshold and myocardial segment infarct score. Secondary outcomes included the relationship between segmental infarct score and R wave height, and between segmental infarct score and pacing impedance. Data were collected on the feasibility of studying the coronary segments as well as safety. Sixty-five patients presenting with stable coronary artery disease or acute coronary syndromes to Leeds General Infirmary between September 2019 and August 2021 were included in the study. Electrophysiological parameters from segments with an infarct score of zero were obtained, with wide variances seen, with no significant difference in impedance or threshold in any territory. There was a significant difference in sensitivity for segments in the right coronary artery territory for both elective and acute patients. This likely relates to reduced myocardial mass in these territories. No significant association between infarct score and sensitivity, impedance or threshold were seen. This study has established intracoronary electrophysiological parameters in both normal myocardium and areas of myocardial scar. No reliable association was seen between impedance, threshold or R wave amplitude and degree of myocardial viability, contrasting with prior findings from our group and others. More work is therefore required to fully understand the role of transcoronary pacing in this setting.

Assessment of fractional flow reserve in intermediate coronary stenosis using optical coherence tomography-based machine learning.

This study aimed to evaluate and compare the diagnostic accuracy of machine learning (ML)- fractional flow reserve (FFR) based on optical coherence tomography (OCT) with wire-based FFR irrespective of the coronary territory. ML techniques for assessing hemodynamics features including FFR in coronary artery disease have been developed based on various imaging modalities. However, there is no study using OCT-based ML models for all coronary artery territories. OCT and FFR data were obtained for 356 individual coronary lesions in 130 patients. The training and testing groups were divided in a ratio of 4:1. The ML-FFR was derived for the testing group and compared with the wire-based FFR in terms of the diagnosis of ischemia (FFR ≤ 0.80). The mean age of the subjects was 62.6 years. The numbers of the left anterior descending, left circumflex, and right coronary arteries were 130 (36.5%), 110 (30.9%), and 116 (32.6%), respectively. Using seven major features, the ML-FFR showed strong correlation (r = 0.8782, P < 0.001) with the wire-based FFR. The ML-FFR predicted wire-based FFR ≤ 0.80 in the test set with sensitivity of 98.3%, specificity of 61.5%, and overall accuracy of 91.7% (area under the curve: 0.948). External validation showed good correlation (r = 0.7884, P < 0.001) and accuracy of 83.2% (area under the curve: 0.912). OCT-based ML-FFR showed good diagnostic performance in predicting FFR irrespective of the coronary territory. Because the study was a small-size study, the results should be warranted the performance in further large-scale research.

Isolated right ventricular Takotsubo cardiomyopathy in Guillain–Barré syndrome

BackgroundTakotsubo cardiomyopathy can present itself in the most varied clinical forms, with extremely variable electrocardiogram anomalies and presence of comorbidities with a significant systemic commitment. Guillain–Barré Syndrome concomitant with isolated right ventricular Takotsubo cardiomyopathy is a rare entity. Here we present a patient with Guillain–Barré syndrome who had electrocardiogram abnormalities consistent with isolated right ventricular Takotsubo cardiomyopathy which have not been described in literature. This case report may prompt early identification of right ventricular involvement in neurological comorbidities, especially if the electrocardiogram is not frankly suggestive of an acute ischemic condition linked to coronary artery disease.Case presentationA 37-year-old woman was misdiagnosed as acute coronary syndrome because of abnormally elevated troponin T level and electrocardiogram findings in the Emergency Department. Due to absence of any significant stenosis in the main coronary artery, the primary diagnosis was ruled out. Based on reanalysis of the ECG abnormalities, the patient was diagnosed as a case of isolated right ventricular Takotsubo cardiomyopathy in Guillain–Barré Syndrome. This case demonstrates the importance of electrocardiogram as a critical tool to identify isolated right ventricular Takotsubo cardiomyopathy in Guillain–Barré Syndrome. Indeed, in this case, the electrocardiogram abnormalities were distributed beyond the territory of a single coronary artery distribution.ConclusionsThe described electrocardiogram findings of isolated right ventricular Takotsubo cardiomyopathy in Guillain–Barré Syndrome may facilitate identification of right ventricular involvement in neurological diseases.

Influence of age at surgery on left ventricular strain in patients with anomalous origin of left coronary artery from pulmonary artery.

Myocardial strain abnormalities are described after surgical repair of anomalous left coronary artery from pulmonary artery (ALCAPA) even after recovery of ventricular function. The factors that predispose to the presence of these strain abnormalities in the presence of normal ventricular function are unknown. The aim of this study was to find out whether the age at repair influences the presence of global and regional strain abnormalities on follow-up. Repaired ALCAPA patients from a single centre (n = 40) with good ventricular ejection fraction on follow-up were recruited. Baseline and follow-up data were collected from electronic records. Global and regional myocardial strain assessment was done by speckle tracking echocardiography prospectively. The association between age at repair and strain abnormalities on follow-up was analysed. The patients who presented earlier had significantly worse ventricular function pre-operatively compared to older patients (P < 0.0005). Global longitudinal strain was abnormal in 40% of patients with normal ventricular ejection fraction on follow-up. Presence of longitudinal strain abnormalities was more in patients who underwent repair at older age than in those who were repaired earlier (P < 0.0005). The probability of having normal longitudinal strain on follow-up was 81.6% if surgery was done before 7.8 months of age. If operated before 6 months, the odds of having normal myocardial strain was 11 times higher. Regional strain abnormalities of varying severity were present in all patients in the left and in some patients in the right coronary artery territories. Older age at ALCAPA repair is associated with increased incidence of myocardial strain abnormalities. Regional strain abnormalities were found in both left and right coronary artery territories.

Shark Fin Electrocardiogram in the Intensive Care Unit.

Shark Fin Electrocardiogram in the Intensive Care Unit.