Prospective Deep Learning-based Quantitative Assessment of Coronary Plaque by CT Angiography Compared with Intravascular Ultrasound.

AIMS: Coronary computed tomography angiography provides noninvasive assessment of coronary stenosis severity and flow impairment. Automated artificial intelligence analysis may assist in precise quantification and characterization of coronary atherosclerosis, enabling patient-specific risk determination and management strategies. This multicenter international study compared an automated deep-learning-based method for segmenting coronary atherosclerosis in coronary computed tomography angiography (CCTA) against the reference standard of intravascular ultrasound (IVUS). METHODS AND RESULTS: The study included clinically stable patients with known coronary artery disease from 15 centers in the U.S. and Japan. An artificial intelligence (AI)-enabled plaque analysis service was utilized to quantify and characterize total plaque (TPV), vessel, lumen, calcified plaque (CP), non-calcified plaque (NCP), and low attenuation plaque (LAP) volumes derived from CCTA and compared with IVUS measurements in a blinded, core laboratory-adjudicated fashion. In 237 patients, 432 lesions were assessed; mean lesion length was 24.5 mm. Mean IVUS-TPV was 186.0 mm3. AI-enabled plaque analysis on CCTA showed strong correlation and high accuracy when compared with IVUS; correlation coefficient, slope, and Y intercept for TPV were 0.91, 0.99, and 1.87, respectively; for CP volume 0.91, 1.05, and 5.32, respectively; and for NCP volume 0.87, 0.98, and 15.24, respectively. Bland-Altman analysis demonstrated strong agreement with little bias for these measurements. CONCLUSIONS: Artificial intelligence enabled CCTA quantification and characterization of atherosclerosis demonstrated strong agreement with IVUS reference standard measurements. This tool may prove effective for accurate evaluation of coronary atherosclerotic burden and cardiovascular risk assessment.[ClinicalTrails.gov identifier: NCT05138289].

Application of Transcranial Sonography for the Assessment of Brain Midline Shift in Patients Presenting With Suspected Intracranial Pathology to the Emergency Department of a Tertiary Care Hospital in Central Gujarat, India.

BACKGROUND: A shift in midline brain structure indicates raised intracranial pressure (ICP), thereby a sign of compromised perfusion to brain tissues or a mass effect. Early diagnosis can help in planning timely neurosurgical interventions that could prevent further neuron loss. Also, this may aid in neuroprognostication. OBJECTIVES: The objectives of the study were to find the accuracy of bedside assessment of brain midline shift (MLS) using transcranial sonography (TCS) in comparison to a computed tomography (CT) scan of the brain for patients presenting with suspected intracranial pathology to the emergency department (ED). METHODS: This prospective observational study was carried out for one year in an ED. A total of 124 patients with suspected intracranial pathology were included in the study. Transtemporal scanning along the orbitomeatal line was performed to image the third ventricle. The distance between the third ventricle and the internal side of the temporal bone was measured on both sides as A and B. The MLS was then calculated using the following formula: midline shift = (A-B)/2. The data were entered and analyzed using a Microsoft Excel worksheet (Microsoft Corp., Redmond, WA). RESULTS: Out of the total 124 patients enrolled in this study, adequate views for 12 patients were not obtained and, hence, they were excluded from the study. The time to perform a TCS assessment of brain MLS was around 22 minutes (range: 15-30 minutes). In our study, out of 112 analyzed patients, 33 (29.5% of our study) had a significant MLS in the brain (defined by an MLS of more than 5 mm) diagnosed by TCS. Analyzing CT brain results revealed that out of the total 112 patients under study, 27 had a significant brain MLS (24.1% of the total population under study) as defined above. CONCLUSION: A TCS is a promising alternative to a brain CT in an emergency for brain MLS detection.

Coronary computed tomography angiography-based SYNTAX score for comprehensive assessment of advanced coronary artery disease.

BACKGROUND: Since the initial attempt to adapt the anatomical SYNTAX score (aSS) to coronary computed tomography angiography (CCTA), CCTA imaging technology has evolved, and is currently used as a "decision-maker" for revascularization strategy in complex coronary artery disease (CAD) and has rendered necessary some updating of the aSS to the CCTA modality. OBJECTIVES: The aim is to provide updated definitions of the aSS derived from CCTA in patients with complex CAD undergoing CABG. METHODS: The modifications of CCTA-aSS are the following; (i) updated definition and detection criteria of total occlusion (TO) in CCTA based on length assessment, (ii) inclusion of scoring points for serial bifurcations located in one single coronary segment. (iii) inclusion of weighing score points for lesions located distal to a TO, not visualized on conventional coronary angiography, but visible in CCTA, (iv) removal of thrombus and bridging collateral items from the weighing score, considering the limited diagnostic capability of CCTA in detecting these specific lesion characteristics. RESULTS: the updated CCTA-aSS was tested in a first-in-man study using the sole guidance of CCTA for the planning and performance of bypass surgery in complex CAD (n â€‹= â€‹114). An interobserver analysis showed excellent reproducibility (ICC â€‹= â€‹0.96, 95 â€‹% confidence interval 0.94-0.97). CONCLUSION: The updated CCTA-aSS was implemented in a cohort of patients with complex CAD undergoing CABG with the sole guidance of CCTA and FFRCT and the Inter-reproducibility of the analysis of the updated score was found excellent. The prognostic value of the modified CCTA-aSS will be examined in future studies.

Use of angled-tip aspiration catheters is associated with a lower cost of thrombectomy in patients with acute ischemic stroke secondary to large and medium vessel occlusions.

BACKGROUND: Recently, the angled-tip Zoom™ aspiration catheters were introduced. The tip is designed to improve suction force for clot retrieval. We evaluated the possibility of reducing procedure costs when using angled-tip catheters and compared the safety and angiographic effectiveness of angled-tip versus straight-tip catheters. METHODS: We conducted a retrospective single-center cohort study involving patients with acute ischemic stroke due to large and medium vessel occlusions. The patients were divided into two groups: the post-Zoom group, in which angled-tip aspiration catheters were used and the pre-Zoom group, in which traditional straight-tip catheters were employed. RESULTS: A total of 163 patients were included; 95 (58.3%) in the pre-Zoom group and 68 (41.7%) in the post-Zoom group. The groups were well-matched at entry. The post-Zoom group demonstrated a significant decrease in mean procedure cost ($9728 vs. $12,127; p = 0.002), shorter time to achieve modified thrombolysis in cerebral infarction ≥2b reperfusion (38.30 min vs. 53.26 min; p = 0.018), and shorter puncture to procedure completion time (46.42 min vs. 62.38 min; p = 0.022). Additionally, the mean procedural cost when using the ADAPT technique supported by the Zoom catheters was significantly lower than the Solumbra technique ($5754 ± $2806 vs. $13,498 ± $3244, p < 0.001). There were no differences in the rate of hemorrhage between the pre-Zoom group (17.9%) and the post-Zoom group (20.6%), p = 0.690. CONCLUSION: The study demonstrated significant benefits, including cost reduction and shorter time to achieve reperfusion in patients treated with Zoom aspiration catheters. These findings support the use of angled-tip catheters in acute ischemic stroke management.

Assessment of the Efficacy and Safety of Early Intracoronary Nicorandil Administration in Patients With ST-Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention.

Background No-reflow phenomenon (NRP) remains a challenge in ST-elevation myocardial infarction (STEMI) patients. We determined the efficacy and safety of early intracoronary administration of nicorandil as an adjunct to primary percutaneous coronary intervention (pPCI) in STEMI patients to reduce the risk of NRP. Materials and methods In this single-center case-control prospective study, 100 STEMI patients who underwent pPCI had thrombectomy performed using a suction catheter, and tirofiban (10 mg/kg) was injected distal to the vascular lesion. All patients were divided into two groups. Group A was a treatment group (nicorandil, n=50) and group B was a control group (placebo, n=50). The primary endpoint was the composite endpoint of in-hospital cardiovascular mortality or unscheduled re-hospitalization due to deterioration of congestive heart failure that was assessed with the help of brain natriuretic peptide (BNP), left ventricular end-diastolic diameter (LVEDD), and left ventricular ejection fraction at six months following pPCI. The secondary endpoints were thrombolysis in myocardial infarction (TIMI) flow grade, TIMI myocardial perfusion grade (TMPG), the incidence of reperfusion arrhythmias like ventricular tachycardia and ventricular fibrillation, and ST segment elevation resolution (STR) on ECG following pPCI. Results The in-hospital cardiovascular mortality and re-hospitalization rates were 2% and 6% in the nicorandil group, whereas it was 6% and 14% in the control group. On the 180th day of admission, the nicorandil group had significantly lower values of brain natriuretic peptide (348.45±112.32 pg/ml vs. 541.11±152.68 pg/ml, p=0.021) and left ventricular end-diastolic diameter (54.12±3.56 mm vs. 60.62±4.98 mm, p=0.011) than the control group. Nicorandil group had a significantly higher number of patients who attained TIMI 3 (p=0.022), TMPG 3 (p=0.034), and STR (p=0.008) than the control group. Ventricular arrhythmia was significantly lower in the nicorandil group than in the control group at 24 hours following pPCI (p=0.012). Conclusion Early intracoronary administration of nicorandil during pPCI may decrease the occurrence of NRP, in-hospital cardiovascular mortality, and re-hospitalization rates, as well as improve coronary blood flow and reduce reperfusion arrhythmia in STEMI patients.

Strengthening health promotion development with Aboriginal and Torres Strait Islander males in remote Australia: A Northern Territory perspective.

AIMS: To elucidate key considerations for effective health promotion with Aboriginal and Torres Strait Islander males in remote Northern Territory. CONTEXT: Despite the significant disparities in health outcomes amongst Aboriginal and Torres Strait Islander males, particularly in remote Northern Territory, investment in health promotion policy and practice has been inadequate. Progressing towards self-determination with Aboriginal and Torres Strait Islander males, and to meet the unique health and well-being needs of this marginalised demographic, consideration for staff retention and training, strengths-based approaches, and implications of divergent masculinities must be considered when devising and delivering culturally responsive and appropriate health promotion interventions. Health promotion needs to be conducted in a collaborative manner, and in less conventional settings, to better engage Aboriginal and Torres Strait Islander males. APPROACH: This commentary draws on the author's reflections about working in remote Aboriginal and Torres Strait Islander health policy, practice and research contexts in Northern Australia. It brings together diffuse strands of scholarship about Aboriginal and Torres Strait Islander male health; Aboriginal and Torres Strait Islander health promotion; and health promotion in rural and remote contexts. In doing so, we identify and discuss strategies that have potential to strengthen Aboriginal and Torres Strait Islander male health promotion in rural and remote Australia. CONCLUSION: Health services and professionals in remote Northern Territory must leverage the inherent strengths of Aboriginal and Torres Strait Islander males to imbue service delivery with both meaning and capacity for self-determination. In doing so, this might ultimately help to alleviate the marginalisation of this demographic.

Increased Prognostic Yield by Combined Assessment of Non-Contrast Computed Tomography Markers of Antithrombotic-Related Spontaneous Intracerebral Hemorrhage Expansion.

Background and aims: The utility of proposed non-contrast computed tomography (NCCT) markers for the prediction of hematoma expansion in patients with antithrombotic-related spontaneous intracerebral hemorrhage (ICH) is limited. Additionally, there is significant overlap between different suggested ICH shape and density markers. Methods: We assessed the prognostic yield for hematoma expansion of a combined score incorporating features of ICH shape irregularity (satellite sign and/or Barras score ≥ 3), heterogeneous ICH density (swirl sign and/or Barras score ≥ 3) on baseline NCCT and timing from ICH onset to NCCT. Results: We evaluated data from 79 patients with antithrombotic-related spontaneous ICH (32% with hematoma expansion). Swirl (84% vs. 39%) and satellite signs (20% vs. 7%) on baseline NCCT were significantly more prevalent (p < 0.001) in patients with hematoma expansion. Patients with hematoma expansion had more irregular and heterogeneous bleeds on baseline NCCT scans, as quantified by higher (p < 0.001) Barras shape (4 (4−5) vs. 3 (2−4)) and density scores (4 (3−5) vs. 2 (1−3)), respectively. The overall diagnostic yield of the combined score (area under the curve: 0.86, 95%CI: 0.78−0.94) significantly outperformed (p < 0.001) the diagnostic yield of each individual marker. Scores of 4 or 5 in the combined score were associated with a sensitivity of 60.0%, specificity of 90.7%, overall diagnostic accuracy of 81.0%, positive likelihood ratio (LR) of 6.48, negative LR of 0.44, positive predictive value (PV) of 0.76 and negative PV of 0.83. Conclusion: Combined NCCT marker assessment seems to increase the prognostic accuracy for hematoma expansion in antithrombotic-related spontaneous ICH patients.

"It started 30 years ago, and it still haunts me": an exploratory investigation of Territorians' gambling behaviours, harm, and help-seeking for gambling issues in an Australian jurisdiction.

BACKGROUND: There is a lack of qualitative gambling research on lived experience, help-seeking, and gamblers and affected others' views on the regulatory environment in the Northern Territory (NT), Australia. This study provides 1) lived experience of individuals who reported experiencing harms from gambling, 2) insights into help-seeking for gambling issues, 3) and people's views on current legislation on gambling in the NT. The results of this study begin to establish an evidence base that could be used to inform targeted interventions for people experiencing harms from gambling in the NT. METHODS: Semi-structured interviews were conducted with a targeted selection of respondents from the 2015 and 2018 NT Gambling Prevalence and Wellbeing Surveys. The sample (n = 27; age 18+ years; Aboriginal (The term of 'Aboriginal' has used been used throughout the manuscript to reflect Aboriginal and Torres Strait Islander, Indigenous, or First Nations people for purposes of brevity. We respect the diversity among these populations.) and Non-Aboriginal) included weekly (online and venue-based electronic gambling machine (EGM)) gamblers, non-regular gamblers, and those negatively affected by others' gambling. A Framework Analysis approach was used for data analysis. Appropriate ethics approval was obtained. RESULTS: Negative impacts and harms from gambling were experienced by both gamblers and non-gamblers. These included monetary losses, relationship conflicts, emotional distress, and decrements to health. A lack of self-realisation of gambling issues and awareness of the available services, shame, and embarrassment, were reported as the main barriers to help-seeking. Where help was sought, it was primarily informal (e.g., family) and was rarely preventive. In many instances, self-help strategies were successful in controlling one's own gambling. Gamblers suggested regulations should set limits on the daily number of hours of playing, the bet size, and reduced access to EGM. The need for strengthening the existing awareness and education interventions was emphasised. CONCLUSIONS: Viewing the findings from a public health lens, targeted approaches based on specific circumstances may have the potential to minimise harms from gambling, but only for those already experiencing harms. The treatment, policy, and regulatory approaches need to be tailored to address the causes and impacts of harms experienced by people.

Assessment of validity and reliability of femoral shaft-patellar tendon angle measured on MRI.

INTRODUCTION: Clinically measured Quadriceps angle (Q-angle) has low reliability. Measurement of angle between femoral shaft and patellar tendon (FSPT angle) on routine knee MRI was described in this study to represent the lateral vector forces of quadriceps mechanism. The cross-sectional study was designed to compare this angle between subjects with objective patellofemoral instability (PFI) versus those without PFI, to assess its reliability, and to assess its validity in terms of its ability to differentiate between PFI and non-PFI subjects using the "Receiver Operating Characteristic" (ROC) curve. MATERIALS AND METHODS: MRI scans of 20 subjects with PFI and 20 without PFI were obtained. FSPT angle was measured in each MRI by three different raters. In addition, the clinical Q-angle was also measured in the control group. RESULTS: The FSPT angle was significantly higher in PFI group as compared with the non-PFI group (p < 0.001). It had substantial inter-rater reliability of 0.82 (95% CI = 0.67-0.92) in the non-PFI group and 0.89 (95% CI = 0.78-0.95) in the PFI group. Test-retest reliability was more than 0.90. The AUC for the ROC curve was 0.86 (95% CI = 0.74-0.97). The clinical Q-angle measured in non-PFI subjects had inter-rater reliability of only 0.48 (95% CI = 0.21-0.72), and showed a fair correlation of 0.58 with the MRI angle. CONCLUSION: Measurement of FSPT angle was described on MRI with substantial intra-rater and inter-rater reliability. The angle was significantly higher in PFI versus non-PFI subjects and also showed a good ability to differentiate between these two groups in the ROC curve.

A scoping review about social and emotional wellbeing programs and services targeting Aboriginal and Torres Strait Islander young people in Australia: understanding the principles guiding promising practice.

BACKGROUND: Multiple culturally-oriented programs, services, and frameworks have emerged in recent decades to support the social and emotional wellbeing (SEWB) of Aboriginal and Torres Strait Islander (Aboriginal) people in Australia. Although there are some common elements, principles, and methods, few attempts have been made to integrate them into a set of guidelines for policy and practice settings. This review aims to identify key practices adopted by programs and services that align with the principles of the National Strategic Framework for Aboriginal and Torres Strait Islander Peoples' Mental Health and Social and Emotional Wellbeing 2017-2023. METHODS: A comprehensive review of electronic databases and organisational websites was conducted to retrieve studies of relevance. Twenty-seven publications were included in the review. Next, we identified promising practices through a collaborative review process. We then used the principles articulated in the above-mentioned framework as the basis to complete a framework analysis. This enabled us to explore the alignment between current scholarship about SEWB programs and services with respect to the principles of the framework. RESULTS: We found there was a strong alignment, with selected principles being effectively incorporated into most SEWB program and service delivery contexts. However, only one study incorporated all nine principles, using them as conceptual framework. Additionally, 'capacity building', 'individual skill development', and 'development of maladaptive coping mechanisms' were identified as common factors in SEWB program planning and delivery for Aboriginal people. CONCLUSION: We argue the selective application of nationally agreed principles in SEWB programs and services, alongside a paucity of scholarship relating to promising practices in young people-oriented SEWB programs and services, are two areas that need the urgent attention of commissioners and service providers tasked with funding, planning, and implementing SEWB programs and services for Aboriginal people. Embedding robust participatory action research and evaluation approaches into the design of such services and programs will help to build the necessary evidence-base to achieve improved SEWB health outcomes among Aboriginal people, particularly young people with severe and complex mental health needs.

Mosquitoes as a feasible sentinel group for anti-malarial resistance surveillance by Next Generation Sequencing of Plasmodium falciparum.

BACKGROUND: Plasmodium falciparum drug resistance surveillance is key to successful disease control and eradication. Contemporary methods that only allow determination of prevalence of resistance are expensive, time consuming and require ethical considerations. A newer method involving Next Generation Sequencing (NGS) permits obtaining frequency of resistance while allowing to detect minority variants in mixed infections. Here, NGS was tested for P. falciparum resistance marker detection in mosquito samples as a feasible and suitable alternative for molecular resistance surveillance. Anopheles funestus were collected in southern Mozambique using CDC light traps and manual collections. DNA was extracted from either whole mosquito, head-thorax and abdomen separately or pools of five mosquitoes. These samples were screened for P. falciparum and if positive for k13, pfcrt, pfmdr1, pfdhps and pfdhfr mutations related to anti-malarial drug resistance with Sanger sequencing and NGS. RESULTS: Among the 846 samples screened for P. falciparum, 122 were positive by 18S ssrDNA qPCR with an infection rate of 23.6%. No mutations were observed for k13 and pfcrt72-76 and almost zero for pfmdr86, but quintuple pfdhfr/pfdhps mutations were near fixation and about half of the isolates contained the pfmdr184F polymorphism. Similar allele frequencies of resistance markers were estimated with NGS in comparison with the prevalence of markers obtained with the gold standard Sanger sequencing. CONCLUSIONS: Pooled deep sequencing of P. falciparum isolates extracted from mosquitoes is a promising, efficient and cost-effective method to quantify allele frequencies at population level which allows to detect known and unknown markers of resistance in single and mixed infections in a timelier manner. Using mosquitoes as sentinel group and focusing on allele frequency opposed to prevalence, permits active surveillance across a more homogeneous geographical range.

Novel Noninvasive Assessment of Pulmonary Arterial Stiffness Using Velocity Transfer Function.

Background Pulmonary artery ( PA ) stiffness is associated with increased pulmonary vascular resistance ( PVR ). PA stiffness is accurately described by invasive PA impedance because it considers pulsatile blood flow through elastic PA s. We hypothesized that PA stiffness and impedance could be evaluated noninvasively by PA velocity transfer function ( VTF ), calculated as a ratio of the frequency spectra of output/input mean velocity profiles in PA s. Methods and Results In 20 participants (55±19 years, 14 women) undergoing clinically indicated right-sided heart catheterization, comprehensive phase-contrast and cine-cardiac magnetic resonance imaging was performed to calculate PA VTF , along with right ventricular mass and function. PA impedance was measured as a ratio of frequency spectra of invasive PA pressure and echocardiographically derived PA flow waveforms. Mean PA pressure was 29.5±13.6 mm Hg, and PVR was 3.5±2.8 Wood units. A mixed-effects model showed VTF was significantly associated with PA impedance independent of elevation in pulmonary capillary wedge pressure ( P=0.005). The mean of higher frequency moduli of VTF correlated with PVR (ρ=0.63; P=0.003) and discriminated subjects with low (n=10) versus elevated PVR (≥2.5 Wood units, n=10), with an area under the curve of 0.95, similar to discrimination by impedance (area under the curve=0.93). VTF had a strong inverse association with right ventricular ejection fraction (ρ=-0.73; P<0.001) and a significant positive correlation with right ventricular mass index (ρ=0.51; P=0.02). Conclusions VTF , a novel right ventricular- PA axis coupling parameter, is a surrogate for PA impedance with the potential to assess PA stiffness and elevation in PVR noninvasively and reliably using cardiac magnetic resonance imaging.

Importance of three-dimensional geometric analysis in the assessment of the athlete's heart.

How the left ventricle remodels in response to a high-volume stimulus is important in evaluating the endurance athlete's heart. Marathoners and patients with isolated, moderate chronic compensated mitral regurgitation (MR) represent physiologic and pathologic forms of eccentric left ventricular (LV) remodeling in response to intermittent and chronic volume overload, respectively. Thus, in this study, magnetic resonance imaging with tissue tagging and 3-dimensional data analysis at rest were performed in 19 marathoners (mean age 39 ± 10 years, 47% women), 17 patients with isolated MR without coronary artery disease or medical therapy (mean age 46 ± 5 years, 53% women), and 24 controls (mean age 45 ± 8 years, 50% women). Marathoners and patients with MR had approximately 35% greater LV end-diastolic volume indexes, approximately 50% greater end-systolic volume indexes, and approximately 34% greater LV stroke volume indexes (p <0.0001) compared to controls. However, marathoners' hearts had increased long-axis length, while those of patients with MR did not differ from the hearts of controls. The hearts of patients with MR had greater LV global and apex sphericity compared to those of marathoners and controls (p <0.0001). Marathoners had normal LV mass/volume ratios and wall thicknesses, whereas these were significantly decreased in the MR group. In marathoners, the baseline LV work rate was similar to that in controls and higher in patients with MR compared to controls. In conclusion, marathoners' hearts achieve elevated stroke volume at rest with adherence to an elliptical shape defined by 3-dimensional geometry and mass/volume ratio. Thus, a comprehensive evaluation of LV geometry and mass/volume ratio may be important in the evaluation of the athlete's heart.

Development and validation of a stability-indicating RP-UPLC method for the quantitative analysis of sparfloxacin.

A rapid, specific, and sensitive ultra-performance liquid chromatographic (UPLC) method for quantitative analysis of sparfloxacin in bulk drug and pharmaceutical formulations has been developed and validated. In this work, a new gradient reversed-phase chromatographic method was developed. The newly developed method is applicable for assay determination of the active pharmaceutical ingredient. The chromatographic separation of sparfloxacin was achieved on a Waters Acquity HSS T-3 column (100 x 2.1 mm, 1.8 microm) within a short runtime of 5 min. The method was validated according to the ICH guidelines with respect to system suitability, linearity, limit of quantitation and detection, precision, accuracy, robustness, and specificity. Forced degradation studies were also performed for sparfloxacin bulk drug samples to demonstrate the stability indicating power of the UPLC method. Comparison of system performance with conventional HPLC was made with respect to analysis time, efficiency, and sensitivity. The developed method was applied for the assay of marketed sparfloxacin formulations like tablets and eye drops.

A dual propagation contours technique for semi-automated assessment of systolic and diastolic cardiac function by CMR.

BACKGROUND: Although cardiovascular magnetic resonance (CMR) is frequently performed to measure accurate LV volumes and ejection fractions, LV volume-time curves (VTC) derived ejection and filling rates are not routinely calculated due to lack of robust LV segmentation techniques. VTC derived peak filling rates can be used to accurately assess LV diastolic function, an important clinical parameter. We developed a novel geometry-independent dual-contour propagation technique, making use of LV endocardial contours manually drawn at end systole and end diastole, to compute VTC and measured LV ejection and filling rates in hypertensive patients and normal volunteers. METHODS: 39 normal volunteers and 49 hypertensive patients underwent CMR. LV contours were manually drawn on all time frames in 18 normal volunteers. The dual-contour propagation algorithm was used to propagate contours throughout the cardiac cycle. The results were compared to those obtained with single-contour propagation (using either end-diastolic or end-systolic contours) and commercially available software. We then used the dual-contour propagation technique to measure peak ejection rate (PER) and peak early diastolic and late diastolic filling rates (ePFR and aPFR) in all normal volunteers and hypertensive patients. RESULTS: Compared to single-contour propagation methods and the commercial method, VTC by dual-contour propagation showed significantly better agreement with manually-derived VTC. Ejection and filling rates by dual-contour propagation agreed with manual (dual-contour - manual PER: -0.12 +/- 0.08; ePFR: -0.07 +/- 0.07; aPFR: 0.06 +/- 0.03 EDV/s, all P = NS). However, the time for the manual method was approximately 4 hours per study versus approximately 7 minutes for dual-contour propagation. LV systolic function measured by LVEF and PER did not differ between normal volunteers and hypertensive patients. However, ePFR was lower in hypertensive patients vs. normal volunteers, while aPFR was higher, indicative of altered diastolic filling rates in hypertensive patients. CONCLUSION: Dual-propagated contours can accurately measure both systolic and diastolic volumetric indices that can be applied in a routine clinical CMR environment. With dual-contour propagation, the user interaction that is routinely performed to measure LVEF is leveraged to obtain additional clinically relevant parameters.

Right ventricular function assessment: comparison of geometric and visual method to short-axis slice summation method.

BACKGROUND: Short-axis summation (SAS) method applied for right ventricular (RV) volumes and right ventricular ejection fraction (RVEF) measurement with cardiac MRI is time consuming and cumbersome to use. A simplified RVEF measurement is desirable. We compare two such methods, a simplified ellipsoid geometric method (GM) and visual estimate, to the SAS method to determine their accuracy and reproducibility. METHODS: Forty patients undergoing cine cardiac MRI scan were enrolled. The images acquired were analyzed by the SAS method, the GM (area and length measurement from two orthogonal planes) and visual estimate. RVEF was calculated using all three methods and RV volumes using the SAS and GM. Bland-Altman analysis was applied to test the agreement between the various measurements. RESULTS: Mean RVEF was 49 +/- 12% measured by SAS method, 54 +/- 12% by the GM, and 49 +/- 11% by visual estimate. There were similar bias and limits of agreement between the visual estimate and the GM compared to SAS. The interobserver variability showed a bias close to zero with limits of agreement within +/-10% absolute increments of RVEF in 35 of the patients. The RV end-diastolic volume by GM showed wider limits of agreement. The RV end-systolic volume by GM was underestimated by around 10 ml compared to SAS. CONCLUSION: Both the visual estimate and the GM had similar bias and limits of agreement when compared to SAS. Though the end-systolic measurement is somewhat underestimated, the geometric method may be useful for serial volume measurements.

Assessment of myocardial viability by cardiovascular magnetic resonance.

Patients with ischemic heart disease may have left ventricular (LV) dysfunction due to reversible or irreversible causes. The ability to distinguish viable myocardium with dysfunction due to a reversible etiology (hibernation, stunning) from nonviable scar is critical for determining proper management of the patient. Cardiovascular magnetic resonance (CMR) is a technique that has been established to be useful for the detection of myocardial viability and advancements in the field promise to further increase its utility. In this review we describe the features of CMR that make it suited for this purpose and outline promising developments that may soon make CMR the reference standard for viability assessment.