Search

• The Cyberknife cardiac treatments by tracking a single marker were investigated. • The displacement during the tracking and needed planning margins were studied. • The dosimetric accuracy of the treatment was verified. • The results show that the margin increases with the lesion's distance from the lead. • The tracking with a single marker is feasible considering residual planning margins. Within the STRA-MI-VT phase Ib/II trial (NCT04066517), the aim of this phantom study was to explore the feasibility of Cyberknife treatments on cardiac lesions by tracking as a single marker the lead tip of an implantable cardioverter defibrillator. The residual displacement of the lesion during the tracking was studied, planning margins were found and the dosimetric accuracy of the treatment was checked. A lead was inserted into a phantom (EasyCube phantom, Sun Nuclear Co, USA) and then placed on the translating ExacTrac Gating System (BrainLAB AG, Germany). The phantom was rotated, a virtual lesion was identified and its displacement during the tracking was studied. Two plans were compared, calculated on the unrotated volume and on the envelope of the unrotated and the rotated volumes. The plans were delivered using the Cyberknife System (Accuray Inc, USA) and their dosimetric accuracy verified by gamma analysis with gafchromic films. The residual margin increases enhancing the distance between the lead and the lesion. It is 4 mm for distance 0 cm and 5 mm for distance 5 cm. The coverage is reduced by 3.8% (interquartile range 2.5%–4.7%) when the dose is prescribed on the unrotated volume. All treatment plans are accurate and 3% 3 mm gamma analysis results are greater than 94%. Results showed that tracking with a single marker is feasible considering adequate residual planning margins. The volumes could be further reduced by using additional markers, for example by placing them on the patient's skin. [ABSTRACT FROM AUTHOR]

In left atrial appendage occlusion (LAAO), pre-procedural imaging is pivotal to describe the highly variable LAA anatomy and to guide the operator in device sizing and interventional planning. Multiplanar reconstruction and 3D rendering are used for the interpretation of 3D CT datasets. However, this method of review of such imaging, which is mediated by 2D screens, may be limited due to the lack of true 3D visualization of the structures of interest; Mixed Reality (MxR) may further improve the CT-based pre-procedural planning by allowing for real-3D visualizations with holographic replicas of anatomical models. In this manuscript we present a novel software based on MxR and we evaluated its feasibility on different LAA morphologies. The morphological analysis of the holographic anatomical models was successfully applied for all the patients (n ​= ​4) independently from the morphology and it was performed in less than 10 minutes. Our findings suggest that with further developments MxR could have the potential to become a pivotal tool in LAA occlusion planning thanks to the real-3D perception, possibly leading to a more accurate and faster planning phase. [ABSTRACT FROM AUTHOR]

Background: Transcatheter aortic valve implantation (TAVI) is a valid alternative to surgery in high-risk patients with severe aortic stenosis. Aortic annulus (AoA) sizing is crucial for TAVI success. The aim of the study was to compare AoA dimensions measured by multidetector computed tomography (MDCT) vs those obtained with transthoracic (TTE) and transesophageal echocardiography (TEE) for predicting paravalvular aortic regurgitation (PVR) after TAVI. Methods: Aortic annulus maximum diameter, minimum diameter, and area were assessed using MDCT and compared with TTE and TEE diameter and area for predicting PVR after TAVI in 151 patients (45 men, age 81.2 ± 6.4 years). Results: Aortic annulus maximum, minimum diameter, and area detected by MDCT were 25.04 ± 2.39 mm, 21.27 ± 2.10 mm, and 420.87 ± 76.10 mm(2), respectively. Aortic annulus diameter and area measured by TTE and TEE were 21.14 ± 1.94 mm and 353.82 ± 64.57 mm(2) and 22.04 ± 1.94 mm and 384.33 ± 67.30 mm(2), respectively. A good correlation was found between AoA diameters and area evaluated by MDCT vs TTE and TEE (0.61, 0.65, and 0.69 and 0.61, 0.65, and 0.70, respectively), with a mean difference of 3.90 ± 1.98 mm, 0.13 ± 1.67 mm, and 67.05 ± 55.87 mm(2) and 3.0 ± 2.0 mm, 0.77 ± 1.70 mm, and 36.54 ± 56.43 mm(2), respectively. Grade ≥2 PVR occurred in 46 patients and was related to male gender, higher body mass index, preprocedural aortic regurgitation, and lower mismatch between the nominal area of the implanted prosthesis and AoA area detected by MDCT. Conclusions: Mismatch between prosthesis area and AoA area detected by MDCT is a better predictor of PVR as compared with echocardiography mismatch. Specific MDCT-based sizing recommendations should be developed. [ABSTRACT FROM AUTHOR]

Aim: To compare the feasibility, accuracy, and effective radiation dose (ED) of multidetector computed tomography (MDCT) in the detection of coronary artery disease using a combined ED-saving strategy including prospective electrocardiogram (ECG) triggering with a short x-ray window and a body mass index (BMI)-adapted imaging protocol using adaptive statistical iterative reconstruction (ASIR; group 1), in comparison with a prospective ECG triggering strategy alone (group 2). Materials and methods: One hundred and seventy patients scheduled for invasive coronary angiography (ICA) were evaluated. Fourteen patients were not eligible for MDCT. The remaining 156 patients were randomized to group 1 (78 patients) and group 2 (78 patients). Eight and 11 patients in groups 1 and 2, respectively, were excluded after randomization because the patients’ heart rates were >65 beats/min. MDCT images were assessed for feasibility, signal-to-noise ration (SNR), and contrast-to-noise ratio (CNR), accuracy in detection of coronary stenoses >50% versus ICA and for ED. Results: The feasibility, SNR, CNR, accuracy in a segment-based and patient-based model were similar in both groups (97 versus 95%, 14.5±3.9 versus 14.2±4.1, 16±4.6 versus 16.5±4.4, 95 versus 94% and 97 versus 99%, respectively). The ED in group 1 was 72% lower than in group 2 (2.1±1.2 versus 7.5±1.8mSv, respectively; p <0.01). Conclusions: The use of a multi-parametric ED saving protocol results in a significant reduction in ED without a negative impact on accuracy. [ABSTRACT FROM AUTHOR]

Aim: To investigate the clinical impact of multidetector computed tomography (MDCT) in patients with a low versus a high pre-test likelihood of coronary artery disease (CAD). Materials and methods: A cohort of 120 patients with suspected CAD, scheduled for conventional coronary angiography, underwent MDCT. Using the American Heart Association (AHA)/American College of Cardiology (ACC) guidelines, the population was divided into two groups: patients with a low (group 1) and a high (group 2) likelihood of CAD. Results: Analysis of all segments showed a high feasibility (92%), and a patient based-model showed excellent sensitivity and negative predictive values (NPV; both 100%) and acceptable specificity and positive predictive values (PPV; 86 and 90%, respectively), with an accuracy of 94%. Using MDCT in patients with lower pre-test likelihoods of CAD, according to the ACC/AHA guidelines, the accuracy remained high (93%); conversely, in patient groups with a high prevalence of CAD, a non-significant reduction in accuracy (85%) occurred using MDCT. Particularly, MDCT can be used effectively to exclude a diagnosis of CAD because of its high sensitivity and NPV (100%), but shows a significant reduction in specificity (58%). This reduction was due to an increase in the false-positive:true-negative ratio because of the higher percentage of calcified plaque (a relative but non-significant increase in false positives), and the high prevalence of CAD (significant reduction in true negatives). No differences were found between MDCT and quantitative coronary angiography (QCA) concerning the number of vessels narrowed. Conclusion: Because of its excellent sensitivity and specificity in patients with a low pre-test likelihood of CAD, MDCT could be helpful in clinical decision-making in this population. [Copyright &y& Elsevier]

Objectives: This study sought to compare clinical, echocardiographic, and cardiopulmonary exercise testing response to cardiac resynchronization therapy (CRT) in patients with unfavorable anatomy of coronary sinus (CS) veins, randomized to transvenous versus surgical left ventricular (LV) lead implantation. Background: CRT efficacy depends on proper positioning of the LV lead over the posterolateral wall. A detailed pre-operative knowledge of CS anatomy might be of pivotal importance to accomplish a proper LV lead placement over this area. Methods: Study population included 40 patients (age 66 ± 4 years) with heart failure and indication to CRT, with unsuitable CS branches anatomy documented by pre-operative multislice computed cardiac tomography; 20 patients (Group 1) underwent surgical minithoracotomic LV lead implantation whereas 20 (Group 2) were implanted transvenously. New York Heart Association functional class, echocardiographic, and cardiopulmonary exercise testing data were assessed before and 1 year after CRT-system implant. Results: In all Group 1 patients, the LV leads were placed over the middle-basal segments of the posterolateral wall of the LV. This was not possible in Group 2 patients. One year after CRT, in Group 1, a significant improvement of New York Heart Association functional class, LV ejection fraction (from 28.8 ± 9.2% to 33.9 ± 7.2%, p < 0.01), LV end-systolic volume (from 165 ± 53 ml to 134 ± 48 ml, p < 0.001), and peak Vo(2)/kg (from 10.4 ± 4.5 ml/kg/min to 13.1 ± 3.1 ml/kg/min, p < 0.02) was observed. However, no improvement was observed in Group 2: LV ejection fraction varied from 27.4 ± 4.8% to 27.4 ± 5.7% (p = 0.9), LV end-systolic volume from 175 ± 46 ml to 166 ± 44 ml (p = 0.15), and peak Vo(2)/kg from 11.2 ± 3.2 ml/kg/min to 11.3 ± 3.4 ml/kg/min (p = 0.9). Changes after CRT between groups were highly significant. Conclusions: In the setting of unfavorable CS branches of anatomy, CRT by a surgical minithoracotomic approach is preferable to transvenous lead implantation. [ABSTRACT FROM AUTHOR]

Prognostication of patients with chronic heart failure (HF) stabilized by therapy may be difficult. Therefore, the aim was to evaluate whether combined assessment of plasma N-terminal pro-B natriuretic peptide (NT-pro-BNP) and Doppler left ventricular (LV) diastolic variables was relevant to the prognosis of patients with stable HF. Outpatients with LV systolic HF (ejection fraction < or =45%), classified using clinical criteria as decompensated (n = 94) and stable HF (n = 219), underwent a complete Doppler echocardiographic study. NT-pro-BNP was measured together with mitral wave velocities, E wave deceleration time, and tissue Doppler early septal annular velocity. Median follow-up was 22 months. Freedom from all-cause mortality or HF hospitalization at 24 months was worst (44%) in patients with decompensated HF, intermediate (58%) in patients with stable HF with NT-pro-BNP higher than the median (>1,129 pg/ml), and best (92%) in patients with lower NT-pro-BNP (log-rank p <0.0001). In patients with stable HF, NT-pro-BNP >1,129 pg/ml (hazard ratio [HR] 2.84, p = 0.003), E wave deceleration time <150 ms (HR 2.31, p = 0.004), and tissue Doppler early septal annular velocity <8 cm/s (HR 2.18, p = 0.01) were predictors of the end point at multivariate analysis. The addition of Doppler LV diastolic variables and NT-pro-BNP significantly improved the chi-square test for outcome prediction (from 14.4 to 46.4). In conclusion, NT-pro-BNP and spectral and tissue Doppler variables of LV diastolic dysfunction added independent and incremental contributions to prognostic stratification of patients with stable HF. [ABSTRACT FROM AUTHOR]