Left Anterior Oblique Research Articles

Virtual Chest Radiographs Developed From Computed Tomography Images for Differentiating Central Venous Versus Misplaced Arterial Lines and for Training Radiologists

Objective Radiographic findings to identify central venous catheter misplacement in the arteries, which can cause lethal complications, have not been fully evaluated, and its training is difficult because it is rare. The purpose of this study is to clarify radiographic findings for differentiating central venous and misplaced arterial lines using virtual chest radiographs and elucidate their usefulness in training radiologists. Methods This retrospective study included 150 patients (mean age, 67 [SD, ±12] years; 97 men) who underwent colon cancer surgery between January 2018 and December 2020. Virtual chest radiographs, including 6 oblique projections at 5° intervals, were developed from the computed tomography images using ray-sum reconstruction. Virtual venous and arterial lines were drawn from the right neck to the superior vena cava and aorta, respectively. Diagnostic abilities, including area under the curve (AUC) analysis of the 7 proposed radiographic findings for differentiating these lines in 100 patients, were evaluated. The diagnostic performance, including AUC analysis by 5 radiologists in the other 50 patients, was compared before and after disclosing these results to the radiologists. Results The findings of crossing over the right paratracheal stripe and running along the paracaval line showed the highest AUC for indicating arterial and venous lines in the frontal, right anterior oblique 15°, and left anterior oblique 15° projections (AUC = 0.992, 0.991, and 0.979, and 1.000, 0.994, and 0.998, respectively). The diagnostic performance of the radiologists improved after informing them of these results (AUC, 0.982–0.999 to 0.993–1.000 [P = 0.145–1.000] for the frontal projections and 0.932–0.970 to 0.967–0.995 [P = 0.075–0.150] for the oblique projections). Conclusions Virtual chest radiographs created from computed tomography images were useful for clarifying radiographic findings for differentiating central venous and misplaced arterial lines and for training radiologists.

Novel technique and assessment of available three-dimensional delivery sheath for endomyocardial biopsy during cardiac device implantation

BackgroundEarly cardiomyopathy diagnosis allows timely treatment and may help resolve problems that occur after cardiac implantable electronic device (CIED) implantation. ObjectiveTo describe a novel technique for endomyocardial biopsy (EMB) using a three-dimensional (3D) delivery sheath during CIED implantation. Additionally, we investigated 3D delivery sheath characteristics using sheath deflection during bioptome insertion. MethodsThis study of 20 patients undergoing CIED implantation analyzed the EMB success rate and pathological findings. Fluoroscopic images assessed 3D delivery sheath characteristics before and after bioptome insertion in three sheaths. CIEDs were implanted for sick sinus syndrome (n=3), atrioventricular conduction disorder (n=16), and left ventricular dysfunction (n=1). Fluoroscopic verification was performed using right anterior oblique (RAO) and left anterior oblique (LAO) views. EMB was performed with Selectra 3D (BIOTRONIK), CSP Locator 3D (Abbott) and SSPC (Boston Scientific) (12, 4, and 4 patients, respectively). The distance moved toward the right ventricular apex (RVA) in RAO was defined as Dis-RAO (mm) and that moved toward the RVA in LAO was defined as Dis-LAO (mm). ResultsAmong the three sheaths, only the CSP Locator 3D and Selectra 3D showed significant differences in Dis-RAO (13.2±2.0mm vs. 19.8±3.8mm, p<0.01) and Dis-LAO (8.1±1.3mm vs. 15.3±3.9mm, p<0.01). A total of 77 EMB samples from 20 patients were collected without any complication, and four patients (20%) were diagnosed with cardiac amyloidosis (CA) based on pathological findings. ConclusionsAll 3D delivery sheaths were safe and effective for performing EMB from the RVS during CIED implantation, enabling early CA diagnosis in 20% of patients.

Dual-chamber CRT-D using ICD lead implantation in the LBBAP position

Abstract Background Interest in conduction system pacing (CSP) has increased in recent years. For left bundle branch area pacing (LBBAP), 4F and 6F pacing leads have been shown to be effective and safe. No information is available on the potential use of ICD leads for LBBAP. Aim The objective of the study was to demonstrate the feasibility of implanting an ICD lead in the LBBAP position to reduce the number of leads for CRT-D therapy. Patients and Methods We implanted the 7F ICD lead in the LBBAP position through a new 10F CSP delivery sheath in ten consecutive patients. Periprocedural data, QRS morphology and degree of QRS reduction were analyzed. Results Ten consecutive patients (one female) aged 69.5±9.2 years were treated with the above-mentioned method. Eight patients had ischemic cardiomyopathy and two patients had nonischemic cardiomyopathy. All patients had a CRT-D indication. Eight patients had a wide QRS complex with complete LBB and a QRS complex of 184.8±25.8 ms. Two patients had a narrow QRS complex but first-degree AV block with a PR interval greater than 240 ms. Left ventricular ejection fraction was 31.8±8.6%. Operative and fluoroscopy times were 103.6±30.3 minutes and 10.5±6.1 minutes, respectively. On average, 1.7 ± 0.6 screwing attempts were required per patient. The intraprocedural LBBAP threshold was 0.78±0.6V/1.0ms, the impedance was 530.8±86.5 ohm, and the R-wave amplitude was 9±3.3mV. The unipolar paced QRS complex was 123.6±15.9ms, the bipolar paced QRS complex was 129.5±12.8ms, and the bipolar paced QRS complex on the next day was 133.3±11.7. The mean duration from stimulus to R-wave peak in lead V6 was 82.9 ± 19.7 ms. The R-wave interpeak interval between leads V6 and V1 was 43.4 ± 9.7 ms. All but one patient received an effective defibrillation threshold test at 30J (n=8) and 36J (n=1). One patient was not tested during the procedure due to high risk. Conclusion This first-in-human study of ICD lead implantation in the LBBAP position demonstrated its feasibility and efficacy in achieving conduction system stimulation. This approach may lead to a reduction in the number of leads implanted for cardiac resynchronization therapy. Figure 1. A- RAO view, angiography of the RV for verification of the TVA-summit. B- LAO view, angiography from the CSP- sheath after reaching final position of the LBBAP lead (right sided interventricular septum - yellow dotted line). C – 12 lead ECG (speed 50mm/sec) demonstrating paced and native QRS complexes. D – Fluoroscopy in RAO view, final result. E – Fluoroscopy in LAO view, final result. F – Transthoracic echocardiography the next day (4Ch view) demonstrates optimal LBBAP lead position.. RAO – right anterior oblique; LAO – left anterior oblique; TVA – tricuspid valve anulus; CSP – conduction system pacing; LBBAP – left bundle branch area pacing.Figure 1.

Usefulness of scintigraphy with [99mTc]Tc-DPD for the detection of transthyretin cardiac amyloidosis. Reference centre experience in an endemic area

Abstract Background Cardiac amyloidosis (CA) is an infiltrative disorder caused by protein deposition, being transthyretin amyloidosis (ATTR) and primary amyloidosis (AL) the most common forms of CA. ATTR can occur in a hereditary form (ATTRv) or wild-type (ATTRwt). Our area is endemic for ATTRv due to the Val30Met mutation. Purpose To analyse the usefulness of scintigraphy with [99mTc]Tc-DPD (DPD-CS) in an endemic area and its relationship with the diagnostic of CA. Methods We conduct a retrospective study (04/2013-12/2022) of DPD-CS performed for suspected/screening of CA. Our acquisition protocol consists of performing planar images after 3h p.i.(anterior, left anterior oblique and left lateral) +/- SPECT/CT. The assessment of myocardial uptake was evaluated using the Perugini scale (PS: 0-3), considering 2 and 3 as positive scans. DPD-CS results were classified based on the suspicion of CA, according to the 2021 ESC guidelines (we considered cardiomyopathy if: left ventricle hypertrophy ≥12 mm + ≥3 typical signs/symptoms), as well as according to their final diagnosis: ATTRv, asymptomatic carriers, ATTRwt, AL, AA and other non-amyloid (NA) causes. Clinical findings were correlated with the results of the DPD-CS. Results 509 DPD-CS were performed in 478 patients (median age:73 years [22-95], 62% men). Median follow-up: 4.17 years. 127/478 patients were classified with cardiomyopathy (131/509 DPD-CS) and 351/478 without cardiomyopathy (378/509 DPD-CS). 115/509 positive DPD-CS (PS-2: 17, PS-3: 98): 113 had cardiomyopathy (55 ATTRv, 60 ATTRwt) and 2 without cardiomyopathy (1 ATTRv, 1 asymptomatic carrier). These latter two patients developed cardiomyopathy during the follow-up. 394/509 negative DPD-CS (PS 0: 387, PS 1: 7): 18 with cardiomyopathy (1 ATTRv, 1 carrier, 3 AL and 13 NA) and 376 without cardiomyopathy (30 asymptomatic carriers, 88 ATTRv, 2 AA, 9 AL and 247 NA). One patient with cardiomyopathy and ATTRv had initial negative DPD-CS, but became positive DPD-CS on follow-up. All ATTRv without cardiomyopathy presented polyneuropathy. Final diagnoses (according to DPD-CS number): 143 ATTRv (140 Val30Met, 2 Val122Ile, 1 Glu495Gln), 32 carriers (29 Val30Met, 2 Val122Ile, 1 His51Asn), 61 ATTRwt,12 AL, 2 AA and 259 NA. The analysis obtained after correlating the results of the DPD-CS regarding the presence of cardiomyopathy was: sensitivity 86.25%, specificity 99.47%, PPV 98.26% and NPV 95.43%. Conclusion Our study reaffirms the usefulness of DPD-CS in the non-invasive diagnosis of transthyretin CA. DPD-CS has an additional value in endemic areas for the early detection of CA in asymptomatic patients.

Novel parameters for micra transcatheter pacing system implantation on the right ventricular mid-septum

Abstract Background No procedural parameters for Micra transcatheter pacing system (Micra TPS) implantation on the right ventricular mid-septum have been established though it is encouraged for safety. Purpose We aimed to investigate procedural predictors for Micra TPS implantation on the ventricular mid-septum. Methods This is a single-center, retrospective and observational study. Eighty-two patients who underwent Micra TPS implantation were enrolled. The implantation sites of the ventricular septum were classified into basal, mid and apical-septum in the right anterior oblique 35° image. Predictors for mid-septal implantation were evaluated using univariable and multivariable logistic regression analysis which involved explanatory variables considered clinically important. The explanatory variables included the angle between the axis of a device cup of a delivery catheter and the tangent of the ventricular septum in the left anterior oblique 45° image (defined as angle θ). The diagnostic cut-off value of the significant predictor for mid-septal Micra implantation was assessed using receiver operating characteristic (ROC) curve analysis. Results Micra TPS was implanted on the ventricular mid-septum in 61 patients (74.4%), the apical-septum in 21 patients (25.6%), and the basal-septum in no patients. In univariable logistic regression analysis, each angle θ and α-loop shape appearance of a delivery catheter was significantly associated with mid-septal implantation (Odds ratio [OR], 1.1; 95% confidential interval [CI], 1.02-1.10; P=0.002, and OR, 4.6; 95% CI, 1.63-13.6; P=0.005, respectively). After multivariable adjustment, both angle θ and α-loop shape appearance were independently associated with mid-septal implantation (adjusted OR, 1.1; 95% CI, 1.01-1.09; P=0.010, and adjusted OR, 3.3; 95% CI, 1.01-11.4; P=0.048, respectively). Because no Micra TPS was implanted on the basal-septum, an ROC curve for binary outcome of mid-septal and apical-septal implantation was drawn. The ROC curve showed a cut-off value of angle θ for Micra TPS implantation on the ventricular mid-septum was 22° with high sensitivity and specificity at 80.0% and 70.0% (area under the curve= 0.781). Conclusion The angle θ ≧ 22°and the α-loop shape appearance of a delivery catheter may be useful predictors for Micra TPS implantation on the ventricular mid-septum.

Extreme left anterior oblique projection guided leadless pacemaker implantation: a pilot study

Abstract Introduction Cardiac perforation with leadless pacemakers (LPM) remains a concern. Non-septal placement seems to be the main cause, with frequent delivery in the right ventricular (RV) free wall when using standard 30-40º left anterior oblique (LAO) projections. Thus, individualized angulations might be considered, because distinguishing septal from free-wall location with standard projections has been proved to be unreliable: previous studies have shown frequent RV free wall position misclassified as septal when using 30-40º LAO. Methods This is a single-center, observational pilot study, comparing a 60º LAO approach LPM (VR or VDD) implant technique with the standard one. All consecutive patients who received LPM using non-standard LAO projections (study cohort) were compared with an immediately retrospective cohort of consecutive patients who received LPM using only standard projections in the same institution (control cohort). In the study group, sequential 30-40º and 60º LAO projections were performed, and a RV transvenous reference was also considered in cases with preexisting pacing leads or by placing an electrophysiological catheter into an apical-septum position upon implanter´s criterion. The primary endpoint was the need of repositioning the delivery catheter in the study cohort, due to unproper position in the 30-40º LAO angulation. The secondary endpoints were: 1) procedural characteristics (procedure and fluoroscopy times, final fluoroscopic device position and number of deployments); 2) procedure related complications (the composite of vascular complications, implant failure, cardiac perforation, and device dislodgement); 3) acute pacing parameters. Results Twenty-one patients who received LPM using both 30-40º and 60º LAO (study cohort) were compared with 84 patients who received LPM using only 30-40º LAO. Delivery catheter repositioning was needed in 73,7% of patients (n=16/21) in the study cohort, most of them (n=14/16, 77,5%) due to catheter towards RV free wall, distinguished with 60º LAO from 30-40º LAO. Placement in non-midseptal locations was more common in the control group compared to the study group (74.7% vs. 42.8%, p=0.006). The median number of delivery attempts was higher in the study group (1.8±1.3 vs. 1.3±0.9, p=0.010), with longer procedural times. Threshold tended to be higher in the study group (0.8±0.7Vx0.4ms vs. 0.5±0.3Vx0.4ms, p=0.063), with smaller R-wave sensing (9.2±3.7mV vs. 11.4±4.4mV, p=0.038) and impedance (757±207ohms vs. 1026±314ohms, p&amp;lt;0.001). Conclusion 60º LAO frequently identified catheter mislocations using 30-40º LAO, helping to avoid RV free wall LPM deployment. This intervention resulted in longer procedures, possibly due to a higher number of repositions and delivery attempts. Pacing parameters remained adequate, although there was a trend for higher threshold, meanwhile sensing and impedance were lower, maybe related to worse myocardial contact when true septal placement is achieved.Study group implant sequenceBaseline and procedural characteristics

Transfemoral leadless pacemaker implantation after tricuspid valve surgery and intervention

Abstract Background and Purpose Pacemaker (PM) implantation after surgical or transcatheter tricuspid valve (TV) repair or replacement may be challenging. Transcatheter leadless pacemaker (LPM) implantation has become a routine procedure and is frequently adopted in patients without the need for an atrial lead, in cases with cardiac implantable device infection or in patients with marked comorbidities. The use of LPM in patients with previous TV repair or replacement has only been described in singular cases in literature. We present our single center experience of LPM implantation after TV repair. Methods Patients with a history of TV repair or replacement who underwent LPM in our institution between 01/2020 and 11/2023 were retrospectively analyzed. All patients underwent routine clinical follow-up investigations including LPM interrogation and transthoracic echocardiography to assess for TV status. For LPM implantation right anterior oblique (RAO) and left anterior oblique (LAO) caudal fluoroscopy projections were utilized to enable LPM device passage across the TV. Results The study population consisted of 10 patients (9 females, mean age 74.0±10.0 years). Two patients had a history of surgical TV annuloplasty repair and two patients a history of surgical valve replacement, four patients of transcatheter TV repair (one through the mitral clip), one patient of transcatheter valve-in-ring bio prosthesis implantation prosthesis after previous surgical ring deployment and one patient transcatheter TV replacement (Figure1). All patients suffered from permanent atrial fibrillation previous to implantation procedures. Three patients were on chronic hemodialysis therapy before LPM implantation. LPM systems were successfully implanted in all cases with a mean procedure time of 43.5±26.5 minutes and a mean fluoroscopy time of 5.9±5.5 minutes and a radiation dose of 1148,7±1424,9 cGy·cm2. For fluoroscopically guided TV crossing a mean LAO angle of 43.6±14.1° (range 22 to 53°) and caudal angle of 8.5±6.9° (range 0 to 20°) was utilized (Figure 2). The LPM device was positioned in the first positioning attempt in a right ventricular high septal localization in 8 cases. Mean pacing threshold was 0.36±0.07 V at 0.25 ms, with a mean sensing amplitude of 10.5±2.9 mV and a mean of 853±324 Ohms pacing impedance. No periprocedural complications occurred. Mean duration of follow-up was 8.1±9.2 months. There were no newly developed TV regurgitations noted. Pacing thresholds (0.37±0.1 V/0.25 ms), sensing amplitude (11.8±4.5 mV) as well as pacing impedances (865±365 Ohms) remained stable until the last follow-up investigation. Conclusion LPM implantation was feasible in patients with a history of TV repair or replacement. LPM implantation was safe and effective in various modalities of TV repair. LPM may be an alternative to conventional pacemaker implantations as well as surgical lead placement in selected patients.Figure 1.Figure 2.

Combining conventional technique with fluoroscopy integration module in accessory pathway ablation.

Accessory pathway (AP) ablation is a straightforward approach with high success rates, but the fluoroscopy time (FT) is significantly longer in conventional technique. Electroanatomical mapping systems (EMS), reduce the FT, but anatomical and activation mapping may prolong the procedure time (PT). The fluoroscopy integration module (FIM) uses prerecorded fluoroscopy images and allows ablation similar to conventional technique without creating an anatomical map. In this study, we investigated the effects of combining the FIM with traditional technique on PT, success, and radiation exposure. A total of 131 patients who had undergone AP ablation were included in our study. In 37 patients, right and left anterior oblique (RAO-LAO) images were acquired after catheter placement and integrated with the FIM. The ablation procedure was then similar to the conventional technique, but without the use of fluoroscopy. For the purpose of acceleration, anatomical and activation maps have not been created. Contact-force catheters were not used. 94 patients underwent conventional ablation using fluoroscopy only. FIM into AP ablation procedures led to a significant reduction in radiation exposure, lowering FT from 7.4 to 2.8 min (p < .001) and dose-area product from 12.47 to 5.8 μGym² (p < .001). While the FIM group experienced a reasonable longer PT (69 vs. 50 min p < .001). FIM reduces FT regardless of operator experience and location of APs CONCLUSION: Combining FIM integration with conventional AP ablation offers reduced radiation exposure without compromising success rates and complication.

Angiographic assessment of vein of Marshall in atrial fibrillation: Implications for identification and cannulation

BackgroundThe vein of Marshall (VOM) ethanol infusion improves rhythm control in atrial fibrillation (AF). The identification and cannulation of the VOM can be technically challenging. This study aimed to assess the angiographic morphology of the VOM and investigate its value in the VOM ethanol infusion. MethodsPatients with AF (n = 162) scheduled for combined catheter ablation and VOM ethanol infusion were enrolled. The VOM morphologic features in the right anterior oblique (RAO), the left anterior oblique (LAO), and the LAO cranial views were analyzed. The impact of morphology on the identification and cannulation of the VOM was investigated. ResultsThe VOM was identified in 159 (98.1 %) and cannulated in 150 (92.6 %) patients. The VOM identification rate in the RAO and LAO/LAO cranial view was 97.3 % and 89.3 %, respectively. Of 134 patients with VOM identification in the LAO/LAO cranial view, 104 (77.6 %) had a VOM ostium clock location (VOMoClock) of ≤3 and 3–4 o'clock. The VOM cannulation success rate in the ≤3, 3–4, 4–5, and 5–6 o'clock groups was 100 %, 92.6 %, 88.5 %, and 77.8 %, respectively (p = 0.032). The median (interquartile range) cannulation time in the four groups was 10.5 (6.3), 12.0 (9.0), 13.0 (23.0), and 34.0 (30.0) minutes, respectively (p < 0.001). The diameter of the coronary sinus ostium in the RAO view and the VOMoClock were independent predictors for difficult cannulation. ConclusionsThe VOM morphologic features in different angiographic views provide valuable information which could facilitate the identification and cannulation of the VOM.

Deep Learning to Estimate Left Ventricular Ejection Fraction From Routine Coronary Angiographic Images

BackgroundCine images during coronary angiography contain a wealth of information besides the assessment of coronary stenosis. We hypothesized that deep learning (DL) can discern moderate-severe left ventricular dysfunction among patients undergoing coronary angiography. ObjectivesThe purpose of this study was to assess the ability of machine learning models in estimating left ventricular ejection fraction (LVEF) from routine coronary angiographic images. MethodsWe developed a combined 3D-convolutional neural network (CNN) and transformer to estimate LVEF for diagnostic coronary angiograms of the left coronary artery (LCA). Two angiograms, left anterior oblique (LAO)-caudal and right anterior oblique (RAO)-cranial projections, were fed into the model simultaneously. The model classified LVEF as significantly reduced (LVEF ≤40%) vs normal or mildly reduced (LVEF>40%). Echocardiogram performed within 30 days served as the gold standard for LVEF. ResultsA collection of 18,809 angiograms from 17,346 patients from Mayo Clinic were included (mean age 67.29; 35% women). Each patient appeared only in the training (70%), validation (10%), or testing set (20%). The model exhibited excellent performance (area under the receiver operator curve [AUC] 0.87; sensitivity 0.77; specificity 0.80) in the training set. The model’s performance exceeded human expert assessment (AUC, sensitivity, and specificity of 0.86, 0.76, and 0.77, respectively) vs (AUC, sensitivity, and specificity of 0.76-0.77, 0.50-0.44, and 0.90-0.93, respectively). In additional sensitivity analyses, combining the LAO and RAO views yielded a higher AUC, sensitivity, and specificity than utilizing either LAO or RAO individually. The original model combining CNN and transformer was superior to DL models using either 3D-CNN or transformers. ConclusionsA novel DL algorithm demonstrated rapid and accurate assessment of LVEF from routine coronary angiography. The algorithm can be used to support clinical decision-making and form the foundation for future models that could extract meaningful data from routine angiography studies.

Cardiac Computed Tomography to Guide the Selection of Better Display Angle of Cardiac Right Ventricular Pacing Electrode in Radiography.

Traditional radiography angles do not adequately reveal the shape and position of the right ventricular pacing electrode. This study aimed to explore better radiography angles with the help of cardiac computed tomography (CT). We analyzed the cardiac CT images of consecutive outpatients from 2018 to 2019. The right anterior oblique (RAO) 30° and the left anterior oblique (LAO) 40° were found to sufficiently display the shape and position of the right ventricular pacing electrode. A total of 214 consecutive outpatients were enrolled, whose average age was 55.0 ± 13.0 years, and 151 were male (70.6%). Through analyzing the cardiac CT images, the α angle (33.7° ± 6.1) and the γ angle (38.8° ± 8.0) were determined. Furthermore, we verified these angles in 48 patients after pacemaker implantation. The results showed that the ratio of the length of right ventricular electrode using the RAO α angle (≈30°) to the posterior-anterior position (PA position) was 1.099 ± 0.157 vs. 1.053 ± 0.182 (the ratio using the traditional RAO 45°) (P < 0.001). We observed that the relationship between the right ventricular active electrode and the ventricular septum was better identified using the LAO γ angle (≈40°) than the traditional 60° angle. With the help of cardiac CT, we found that RAO 30° could better show the shape and length of the right ventricular pacing electrode, and LAO 40° could better show the positional relationship between the pacing electrode and the ventricular septum.

A possible mechanism and predictors of forming looped guidewire between the right subclavian and brachiocephalic artery during coronary angiography with right radial artery access: An original paper.

Guidewire occasionally creates a loop-like appearance between the right subclavian artery and brachiocephalic artery when performing coronary angiography (CAG) with right radial artery (RtRA) access. We called this occurrence a looped guidewire at the brachiocephalic artery (looped GW at BA). It is associated with difficulties in catheter manipulation. This study aimed to assess the predictors of forming a looped GW at the BA. We examined 175 (mean age, 71.3 ± 9.5 years; 74.9% men) consecutive patients who underwent elective CAG with the RtRA access. Looped GW at the BA was defined as a loop-like appearance of the 0.035-inch GW between the right subclavian and brachiocephalic artery on a frontal view or left anterior oblique. To identify the predictors of looped GW at BA, patient characteristics and examination data obtained before CAG were compared between patients with and without looped GW at the BA. The prevalence of looped GW at BA was 10.9%. The cardio-ankle vascular index (CAVI), which reflects arterial stiffness, was significantly different in patients with or without looped GW at BA (9.8 ± 1.0 vs. 8.9 ± 1.5, p = 0.0092). The area under the receiver-operating characteristic curve of CAVI to predict looped GW at BA was 0.745, with 0.94 sensitivity and 0.57 specificity in a cutoff point of CAVI ≥9.0. Looped GW at BA can be ruled out by CAVI and is associated with high arterial stiffness.

Adjustment of acquisition arc in cardiac malposition during myocardial perfusion SPECT imaging: computer simulation based on deterministic modeling

ObjectivesTo simulate cardiac malpositions, leftward and rightward shift and dextrocardia, and also to compare distribution of activity of septal and lateral walls of left ventricle acquired in standard acquisition arc and after relevant adjustment. MethodsIn this study, digital phantoms with cardiac malpositions are designed and procedure of acquisition of scan in standard arc (from right anterior oblique to left posterior oblique) and adjusted acquisition arc is simulated. The three situations of malposition including leftward and rightward shift and dextrocardia are considered. For all types, acquisition is conducted in standard and then adjusted arcs (from anterior to posterior and also from right to left for leftward and rightward shifts, respectively, and for dextrocardia, from left anterior oblique to right posterior oblique). All obtained projections are reconstructed using the algorithm of filtered back projection. During forward projection to obtain sinograms, radiation attenuation is also modeled by incorporation of a simplified transmission map to emission map. The resulting tomographic slices of the LV (septum, apex, and lateral wall) are presented visually and are compared by plotting intensity profiles of the walls. Finally, normalized error images are also computed. All the computations are performed in MATLAB software package. ResultsIn transverse slice, septum and lateral wall are attenuated progressively from apex, which is closer to the camera, to the base in similar fashion. In tomographic slices of standard acquisition arc, the septum shows remarkably higher activity compared to lateral wall. However, after adjustment, both seems equally intense and progressively being attenuated from apex to base, similar to that found in phantom with normally positioned heart. Likewise, for the phantom with rightward shift, when the scanning was done in standard arc, the septum is more intense than the lateral wall. And similarly, adjustment of the arc renders both walls equally intense. In dextrocardia, level of attenuation of basal parts of septum and lateral wall is higher in 360° arc compared to adjusted 180° arc. ConclusionAdjustment of acquisition arc exerts perceptible changes in distribution of activity over LV walls which are more compatible with normally positioned heart.

One-Stage Detection without Segmentation for Multi-Type Coronary Lesions in Angiography Images Using Deep Learning.

It is rare to use the one-stage model without segmentation for the automatic detection of coronary lesions. This study sequentially enrolled 200 patients with significant stenoses and occlusions of the right coronary and categorized their angiography images into two angle views: The CRA (cranial) view of 98 patients with 2453 images and the LAO (left anterior oblique) view of 176 patients with 3338 images. Randomization was performed at the patient level to the training set and test set using a 7:3 ratio. YOLOv5 was adopted as the key model for direct detection. Four types of lesions were studied: Local Stenosis (LS), Diffuse Stenosis (DS), Bifurcation Stenosis (BS), and Chronic Total Occlusion (CTO). At the image level, the precision, recall, mAP@0.1, and mAP@0.5 predicted by the model were 0.64, 0.68, 0.66, and 0.49 in the CRA view and 0.68, 0.73, 0.70, and 0.56 in the LAO view, respectively. At the patient level, the precision, recall, and F1scores predicted by the model were 0.52, 0.91, and 0.65 in the CRA view and 0.50, 0.94, and 0.64 in the LAO view, respectively. YOLOv5 performed the best for lesions of CTO and LS at both the image level and the patient level. In conclusion, the one-stage model without segmentation as YOLOv5 is feasible to be used in automatic coronary lesion detection, with the most suitable types of lesions as LS and CTO.

Venous anatomy of the left ventricular summit region: Insights from high-speed rotational retrograde angiography.

Mapping and ablation through the coronary venous system (CVS) have shown potential for ventricular arrhythmias originating from the left ventricular summit (LVS). Multielectrode catheters and balloons are frequently used for mapping and venous ethanol ablation (VEA). However, there is limited data on the venous size and drainage condition in the LVS region. This study aimed to investigate the morphology, angiographic size, and drainage condition of LV summit veins via high-speed rotational angiography (RA). We measured and analyzed the size of the great cardiac vein (GCV), the anterior interventricular vein (AIV), veins near to the LVS, and other main tributaries of CVS in 102 patients undergoing electrophysiology study. Rotational retrograde angiography of LVS was successfully performed in 81 patients. The diameter of GCV at the level of the Vieussens valve and the distal end of GCV (junction of GCV-AIV) was larger in males than females (6.8 ± 1.1 vs. 5.6 ± 1.2 mm, p < .001; 5.2 ± 0.9 vs. 4.6 ± 0.8, p = .002, respectively) while no significant gender differences were observed in other tributaries. The LV summit veins presented downward drainage direction in half of the patients, indicating potential anatomic adjacency with His bundle. Left anterior oblique (LAO) 45° projection might provide the practical and optimal view of the LV summit veins. The coronary veins of the LVS region present various anatomical morphologies and ostium sizes. We provide a systematic description and angiographic size spectrum of CVS. RA could facilitate assessing the feature of CVS comprehensively.

Impact of Different Right Ventricular Lead Positions on QRS Complex Duration Post Cardiac Resynchronization Therapy Device Implantation

Abstract Aim and objectives The aim of the study was to evaluate the effect of different RV lead positions on QRS complex duration post CRT device implantation in patients indicated for CRT as a treatment of chronic heart failure based on the recommendations of ESC guidelines for diagnosis and treatment of acute and chronic heart failure published in 2016 and to assess the effect of change of QRS complex duration and morphology according to different RV lead positions on clinical response. Patients and Methods This study included 100 patients (age 60.02 ± 7.18) post CRT device implantation presented for follow up at electrophysiology clinics of the cardiology department of Ain Shams university hospitals at least 3 months post CRT device implantation, during the period form from December 2020 till May 2021. The patients were divided into 2 groups according to the site of RV lead implantation after confirmation of the RV lead position by fluoroscope in Right anterior oblique (RAO) and left anterior oblique (LAO) views, 54 patients had the RV lead implanted in the RV Apex (RVA n = 54) and 46 patients had the RV lead implanted in the RV Septum (RVS n = 46). Results OF the total 100 patients that enrolled in our study the rate of non-responders was 19% of the patients showed no clinical improvement, no improvement of NYHA class by at least one grade, 30% of the patients were non-Echocardiographic responders, no improvement of LVEF (Δ EF) by at least 5% with no decrease of LVES diameter by at least 15%, and 15% of the patient were nonECG responders, delta QRS (ΔQRS) didn`t increase by at least 20%. There was no significant difference between the two groups regarding clinical response (NYHA class) (P-value = 0.583), LVEF (Δ EF 6.26 ± 1.64 in RVS group vs. 6.07 ± 1.67 in RVA group, P-value = 0.575) LVES diameter (47.70 ± 8.03 in RVS group vs. 45.39 ± 7.48 in RVA group, P-value = 0.141) or QRS complex narrowing (ΔQRS 60.93 ± 24.68 in RVS group vs. 54.07 ± 26.12 in RVA group, P-value = 0.182). There was no significant difference in the rate of non-responders between the two groups (clinical non responders in RVS group n = 8 vs. RVA group n = 11, P value = 0.547) (Echo non responders in RVS group n = 13 vs. RVA group n = 17, P value = 0.726) (ECG non responders in RVS group n = 6 vs. RVA group n = 9, P value = 0.613), There was an inverse relationship between ΔQRS and clinical response (NYHA) class post CRT device implantation in both RVS and RVA groups (P value 0.016 in RVS group, P value 0.007 in RVA group). Conclusion The study demonstrates that septal RV pacing in CRT is non-inferior to apical RV pacing regarding the primary objective of the study regarding clinical outcome, narrowing of QRS complex (ΔQRS) or LV reverse remodeling, thus no recommendation for optimal RV lead position can hence be drawn from this study. Also, delta QRS complex duration may be used as indicator for electric remodeling and CRT response.

Patient skin dose measurement and risk of deterministic effect during fluoroscopy cardiac procedures.

This study aimed at assessing patient's peak skin doses (PSD) during fluoroscopy cardiac procedures and proposed a look up table to enhance patient's dose management. Perspex phantom and thermoluminescent dosemeters (TLD) were irradiated for different dose levels with X-ray equipment (Philips Azurion 7). It was found that PSD measures were higher than the kerma at the interventional reference point [K (IRP)] reported with factors 1.55, 1.75 and 2.88 for anterior posterior (AP0o), left anterior oblique (LAO45o) and right anterior oblique (RAO45o), respectively. The equations describing the correlation between the PSD measured kerma area product and cumulative air kerma were found with R-square values of 0.98 and 0.99, respectively. The statistical analysis shows a strong linear correlation between PSD and K (IRP) (P-value=0.05). It was also found that 27% of the patients population considered in this work, received a skin dose higher than the threshold of deterministic effect of 2Gy and a look up table with the equation of fitness were proposed to be implemented in the facility for K (IRP) higher than 500mGy.

Identification of Pacemaker Lead Position Using Fluoroscopy to Avoid Significant Tricuspid Regurgitation.

Permanent pacemaker implantation improves survival but can cause tricuspid valve dysfunction in the form of tricuspid regurgitation (TR). The dominant mechanism of pacemaker-mediated TR is lead impingement. This study evaluated the association between the location of the pacemaker leads crossing the tricuspid valve and the incidence of worsening TR and lead impingement using fluoroscopy. Lead positions were evaluated using perpendicular right anterior oblique (RAO) and parallel left anterior oblique (LAO) fluoroscopic angulation views of the tricuspid annulus. A two-dimensional transthoracic echocardiogram (TTE) was performed to evaluate the maximum TR jet area-to-right atrium ratio and define regurgitation severity. A three-dimensional TTE was performed to evaluate lead impingement. A worsening of TR was observed in 23 of 82 subjects. Most leads had an inferior position in the RAO view and a septal position in the LAO view. The mid position in the RAO view and septal position in the LAO view were risk factors for lead impingement. Mid and septal positions were associated with higher risks of significant TR and lead impingement. Lead impingement was associated with a high risk of significant TR. Pacemaker-mediated TR remains a significant problem after lead implantation.

Fluoroscopy integration module reduces radiation exposure without affecting procedure time in accessory pathway ablation

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Conventional Accessory Pathway (AP) ablation is a straightforward approach with high success rates, but the fluoroscopy time is significantly higher. Electroanatomical mapping systems (EMS), reduce the fluoroscopy time, but anatomical reconstruction and activation mapping prolong the procedure time. The Fluoroscopy Integration Module (FIM) uses prerecorded fluoroscopy images and allows ablation similar to conventional technique without creating an anatomical map. In this study, we investigated the effects of combining the FIM with the traditional technique on procedure time, success, and radiation exposure. Methods 112 patients who underwent AP ablation were included in our study. In 18 patients, right and left anterior oblique (RAO -LAO) images were recorded after the insertion of the catheters and integrated with FIM. Afterwards, ablation was performed similarly to the conventional technique but without using fluoroscopy. To accelerate the procedure anatomical and activation maps were not created. Contact-force catheters were not used. 94 patients were ablated conventionally using only fluoroscopy. Results Combining the FIM with the conventional method significantly reduced radiation exposure (Fluoroscopy time: 3,3±2,6 vs 11,5±11,6 sec, p: 0,001; Dose-area-product (DAP): 7,3±6,2 vs. 28,6±40,5 μGym2, p: 0,003) without affecting the total procedure time ( 64,4±15 vs. 62,6±28,7 sec, p: 0,272 ), time to successful ablation ( 33,2±13,9 vs. 29,7±29,5 sec p: 0,056) and radiofrequency application time ( 183,7±94,4 vs. 167,3±89,8 sec p: 0,336). Conclusion These findings suggest that FIM can be used for rapid and successful ablation of APs with reduced radiation exposure times.

Coronary sinus cannulation as real time anatomical landmark to facilitate left bundle branch area pacing

Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction Left bundle branch area pacing (LBBAP) is an established form of conduction system pacing. Innovative fluoroscopic imaging technique with use of radio-opaque contrast in the right ventricle or using pre-mapped His potential has been advocated as an acquired road map to assist in implantation of LBBAP(1) lead. Purpose We aim to explore a different technique by cannulating the coronary sinus (CS) with a sheath and wire to provide real-time anatomical guidance of location of the base of the heart to facilitate more effective LBBAP in a consistent fashion. Methods Prior to LBBAP, the body of the CS is cannulated using an AL2 diagnostic angiographic catheter and a 0.035-inch glidewire. The wire is fixated externally, and fluoroscopic image is acquired before proceeding with deployment of the pacing lead onto an optimal ventricular septal position via standard right (RAO 30) and left anterior oblique (LAO 30) views. From August 2021 to October 2022, we enrolled 12 consecutive patients requiring pacemaker for standard indications and explored the CS cannulation method in delivering LBBAP with either steerable catheters or fixed shape sheaths. Thereafter, we analysed and described the success rates, immediate electrical and device parameters, procedural durations, and clinical events. Results 12 patients were studied. The mean age was 75 ± 13.07 years and 6 (50%) patients were male. 1 (8.3%) was for sinus nodal dysfunction, 10 (83.3%) for atrioventricular block and 1 (8.3%) for atrial fibrillation (AF) control with atrioventricular node ablation. Mean left ventricular ejection fraction was 54.17 ± 8.21 % and baseline QRS was 108.08 ± 23.20ms. LBBAP was successful in all 12 patients based on published criteria with a mean paced QRS duration of 115.25 ± 9.28 ms. The mean total procedure duration was 130.75 +/- 29.84 minutes and mean fluoroscopic duration was 23.17 ± 9.11 minutes. After 1st week post implant, the pacing threshold, sensing, and impedances were stable and acceptable in all the patients. There were no acute complications (e.g. pneumothorax, lead complications, lead dislodgements / perforations) during the periprocedural period. Conclusion(s) The CS cannulation method is a feasible, safe, and effective method to to provide real-time anatomical visualisation of the base of the heart. This facilitates the achievement for optimal LBBAP and can be adopted especially in difficult cardiac anatomies or rotated cardiac silhouettes identified on fluoroscopy.