Regional Wall Motion Analysis Research Articles

Comparison of the left ventricular dyssynchrony between stylet-driven and lumen-less lead technique in left bundle branch area pacing using myocardial perfusion scintigraphy.

Left bundle branch area pacing (LBBAP) has emerged as a novel physiological pacing method to reduce left ventricular (LV) dyssynchrony due to ventricular pacing. Only lumen-less pacing leads (LLLs) with fixed helixes could achieve LBBAP previously, but recently, LBBAP has been performed using stylet-driven leads (SDLs). This study aimed to evaluate the LV dyssynchrony between SDLs and LLLs techniques in LBBAP. We retrospectively evaluated patients who underwent LBBAP with either SDLs or LLLs. We compared both groups' electrocardiogram (ECG) findings and LV dyssynchrony parameters derived from myocardial perfusion scintigraphy. LV dyssynchrony parameters consisted of phase analysis and regional wall motion analysis. We evaluated bandwidth, phase standard deviation (PSD), and entropy in the phase analysis. The time to the end-systolic frame (TES) was calculated in regional wall motion analysis using single-photon emission computed tomography (SPECT). We also evaluated the maximum differences between segmental TES (MDTES), the standard deviation of TES (SDTES), and the difference in the TES between the lateral wall and septum (DTES-LS). In total, 97 patients were enrolled. The success rate of LBBAP did not differ between the groups [SDLs: 47/48 patients (98%) vs. LLLs: 47/51 patients (92%), P=0.36]. The paced QRS duration and the stimulus to the peak LV activation time (stim-LVAT) also did not differ between SDL and LLL groups (122±10 vs. 119±12 ms, P=0.206; 69±12 vs. 66±13 ms, P=0.31, respectively). There were no differences in bandwidth, PSD, and entropy between SDL and LLL groups (73°±37° vs. 86°±47°, P=0.18; 19°±8.5° vs. 21°±9.7°, P=0.19; 0.57±0.08 vs. 0.59±0.08, P=0.17, respectively). The regional wall motion analysis parameters MDTES, SDTES, and DTES-LS also did not differ between SDL and LLL groups (19%±10% vs. 20%±10%, P=0.885; 5.0%±2.5% vs. 5.0%±2.5%, P=0.995; 5.0%±3.7% vs. 4.8%±4.2%, P=0.78, respectively). LBBAP using SDLs was comparable to LV electrical and mechanical synchrony with LLLs.

Stress Echocardiography in Italian Echocardiographic Laboratories: A Survey of the Italian Society of Echocardiography and Cardiovascular Imaging.

The Italian Society of Echography and Cardiovascular Imaging (SIECVI) conducted a national survey to understand the volumes of activity, modalities and stressors used during stress echocardiography (SE) in Italy. We analyzed echocardiography laboratory activities over a month (November 2022). Data were retrieved through an electronic survey based on a structured questionnaire, uploaded on the SIECVI website. Data were obtained from 228 echocardiographic laboratories, and SE examinations were performed in 179 centers (80.6%): 87 centers (47.5%) were in the northern regions of Italy, 33 centers (18.4%) were in the central regions, and 61 (34.1%) in the southern regions. We annotated a total of 4057 SE. We divided the SE centers into three groups, according to the numbers of SE performed: <10 SE (low-volume activity, 40 centers), between 10 and 39 SE (moderate volume activity, 102 centers) and ≥40 SE (high volume activity, 37 centers). Dipyridamole was used in 139 centers (77.6%); exercise in 120 centers (67.0%); dobutamine in 153 centers (85.4%); pacing in 37 centers (21.1%); and adenosine in 7 centers (4.0%). We found a significant difference between the stressors used and volume of activity of the centers, with a progressive increase in the prevalence of number of stressors from low to high volume activity (P = 0.033). The traditional evaluation of regional wall motion of the left ventricle was performed in all centers, with combined assessment of coronary flow velocity reserve (CFVR) in 90 centers (50.3%): there was a significant difference in the centers with different volume of SE activity: the incidence of analysis of CFVR was significantly higher in high volume centers compared to low - moderate - volume (32.5%, 41.0% and 73.0%, respectively, P < 0.001). The lung ultrasound (LUS) was assessed in 67 centers (37.4%). Furthermore for LUS, we found a significant difference in the centers with different volume of SE activity: significantly higher in high volume centers compared to low - moderate - volume (25.0%, 35.3% and 56.8%, respectively, P < 0.001). This nationwide survey demonstrated that SE was significantly widespread and practiced throughout Italy. In addition to the traditional indication to coronary artery disease based on regional wall motion analysis, other indications are emerging with an increase in the use of LUS and CFVR, especially in high-volume centers.

Assessing cardiac mechanical dyssynchrony in left bundle branch area pacing and right ventricular septal pacing using myocardial perfusion scintigraphy in the acute phase of pacemaker implantation.

Left bundle branch area pacing (LBBAP) has recently been reported to be a new, clinically feasible and safe physiological pacing strategy. The present study aims to investigate the usefulness of LBBAP in reducing mechanical dyssynchrony compared with right ventricular septal pacing (RVSP). A total of 39 LBBAP patients, 42 RVSP patients, and 93 healthy control participants were retrospectively evaluated. We compared phase analysis- (bandwidth, phase standard deviation [PSD], entropy) and regional wall motion analysis parameters. Wall motion analysis parameters included the time to the end-systolic frame (TES) assessed using single-photon emission computed tomography analysis. The maximum differences between segmental TES (MDTES), the standard deviation of TES (SDTES), and the TES difference between the lateral and septal segments (DTES-LS) were obtained. All phase analysis parameters were significantly smaller in the LBBAP group than in the RVSP group (bandwidth: LBBAP, 74 ± 31° vs. RVSP, 102 ± 59°, p = .009; PSD: LBBAP, 19 ± 6.7° vs. RVSP, 26 ± 15°, p = .007; entropy: LBBAP, 0.57 ± 0.07 vs. RVSP, 0.62 ± 0.11 p = .009). The regional wall motion analysis parameters were also smaller in the LBBAP group than in the RVSP group (MDTES:LBBAP, 17 ± 7.1% vs. RVSP, 25 ± 14%, p = .004; SDTES:LBBAP, 4.5 ± 1.7% vs. RVSP, 6.0 ± 3.5%, p = .015; DTES-LS: LBBAP, 4.1 ± 3.4% vs. RVSP, 7.1 ± 5.4%, p = .004). All phase analysis and wall motion analysis parameters were same in the LBBAP and control groups. LBBAP may reduce mechanical dyssynchrony and achieve greater physiological ventricular activation than RVSP.

Effect of Intermittent High–Mechanical Index Impulses on Left Ventricular Strain

Intermittent high-mechanical index (MI) impulses from a transthoracic ultrasound transducer are recommended for regional wall motion analysis and assessment of myocardial perfusion following intravenous administration of ultrasound enhancing agents (UEAs). High-MI impulses (>1.0) applied in this setting have also been shown to increase microvascular blood flow through a purinergic signaling pathway, but their effects on left ventricular (LV) myocardial function are unknown. Therefore, the aim of this study was to investigate the effect of transthoracic intermittent high-MI impulses during intravenous UEA infusion in patients with normal and abnormal resting systolic function. Fifty patients referred for echocardiography to evaluate LV systolic function during continuous infusion of UEAs (Definity 3% infusion) were prospectively assigned to low-MI (<0.2) imaging alone (group 1) or low-MI (<0.2) imaging with intermittent high-MI impulses (five frames, 1.8MHz, MI=1.0-1.2) applied at least two times in each apical window to clear myocardial contrast (group 2). Global longitudinal strain (GLS) measurements were obtained at baseline before UEA administration and at 5-min intervals up to 10-min after infusion completion. There were no differences between groups with respect to age, gender, resting GLS, biplane LV ejection fraction, or cardiac risk factors. Resting GLS in group 1 was -15.5±5.2% before UEA infusion and -15.5±5.4% at 10min after UEA infusion. In comparison, GLS increased in group 2 (-15.3±5.0 before infusion and -16.8±4.8% at 10min, P<.00001). Improvements in GLS were seen in patients with normal and abnormal systolic function. Regional analysis demonstrated that the increase in strain in patients with abnormal LV ejection fractions was primarily in the apical segments (-12.0±2.7% before infusion and -13.4±3.4% at 10min, P=.001). High-MI impulses during infusion of a commercially available contrast agent can improve LV systolic function and may have therapeutic effect in patients with LV dysfunction.

The prognostic value of estimating stroke volume before and after exercise during treadmill stress echocardiography.

Stress echocardiography (SE) is an established technique for assessment of coronary artery disease (CAD) which is difficult to perform and interpret. Left ventricular stroke volume (SV) is readily estimated with Doppler echocardiography. It can be affected by myocardial ischemia, with possible adjunctive value during SE. Patients underwent Bruce protocol SE with SV estimated before and after maximal treadmill exertion post routine regional wall analysis. Incremental change in SV (ΔSV) with exercise was measured. A derivation cohort (n=273) was established to test the hypothesis. An optimal cutoff for detection on inducible ischemia was ΔSV ≤ +10mL. The validation cohort of consecutive patients (n=1093, 376 [34%] female; age 59±12years) were followed clinically after SE for 20460 patient-months. There were 1000 patients with nonischemic SE, and 93 patients with studies suggestive of myocardial ischemia. Secondary analysis yielded 831 patients with a normal exercise response (ΔSV>+10mL) and 192 with an abnormal ΔSV ≤ +10mL. Time to first combined adverse cardiac event (composite of angina, acute coronary syndrome, cardiac revascularization, worsening New York Heart Association (NYHA) class, a reduction in EF, and cardiovascular death) was analyzed and adjusted using Cox proportional hazards regression. The hazard ratio for an adverse event with an abnormal ΔSV response (≤10mL) was 10.3 (95% confidence intervals 5.6-19.1, P<.0001). Stroke volume assessment during SE is feasible and readily performed. It is simple, practical, and has incremental diagnostic and prognostic value when added to exercise regional wall-motion analysis.

Quality control of regional wall motion analysis in stress Echo 2020

BackgroundThe trial “Stress Echo (SE) 2020” evaluates novel applications of SE beyond coronary artery disease. The aim of the study was control quality and harmonize reading criteria. MethodsOne reader from 78 centers of the SE 2020 network asked for credentials to read a set of 20 SE video-clips selected by the core lab. All aspiring centers met the pre-requisite of high-volume and the years of experience in SE ranged from 5 to 31years (mean value 18years). The diagnostic gold standard was a reading by the core lab. The a priori determined pass threshold was 18/20 (≥90%). ResultsOf the initial 78 who started, 57 completed the first attempt: individual readers' score on first attempt ranged from 07/20 to 20/20 (accuracy from 35% to 100%, mean 78.7±13%) and 44 readers passed it. There was a very poor correlation between years of experience and the reader's score on first attempt (r=−0.161, p=0.231). Of the 13 readers who failed the first attempt, 12 took it again after the web-based session and their accuracy improved (74% vs. 96%, p<0.001). The kappa inter-observer agreement before and after web-based training was 0.59 on first attempt and rose to 0.91 on the last attempt. ConclusionsIn SE reading, the volume of activity or years of experience is not synonymous with diagnostic quality. Qualitative analysis and operator-dependence can become a limiting weakness in clinical practice, in the absence of strict pathways of learning, credentialing and audit.

P562Upstream quality control of regional wall motion analysis in Stress Echo 2020

P562Upstream quality control of regional wall motion analysis in Stress Echo 2020

Right ventricular strain by MR quantitatively identifies regional dysfunction in patients with arrhythmogenic right ventricular cardiomyopathy

Analysis of regional wall motion of the right ventricle (RV) is primarily qualitative with large interobserver variation in clinical practice. Thus, the purpose of this study was to use feature tracking to analyze regional wall motion abnormalities in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). We enrolled 110 subjects (39 overt ARVC [mutation+/phenotype+] (35.5%), 40 preclinical ARVC [mutation+/phenotype-] (36.3%), and 31 control subjects (28.2%)). Cine steady state free precession cardiac MR was performed with temporal resolution ≤40 ms in the horizontal long axis (HLA), axial, and short axis directions. Regional strain was analyzed using feature tracking software and reproducibility was assessed by means of intraclass correlation coefficient. Dunnett's test was used in univariate analysis for comparisons to control subjects; cumulative odds logistic regression was used for minimally and fully adjusted multivariate models. Strain was significantly impaired in overt ARVC compared with control subjects both globally (P < 0.01) and regionally (all segments of HLA view, P < 0.01). In the HLA view, regional reproducibility was excellent within (intraclass correlation coefficient [ICC] = 0.81) and moderate between (ICC = 0.62) observers. Using a threshold of -31% subtricuspid strain in the HLA view, the sensitivity and specificity for overt ARVC were 75.0% and 78.2%, respectively. In multivariable analysis involving all three groups, subtricuspid strain less than -31% (beta = 1.38; P = 0.014) and RV end diastolic volume index (beta = 0.06; P = 0.001) were significant predictors of disease presence. RV strain can be reproducibly assessed with MR feature tracking, and regional strain is abnormal in overt ARVC compared with control subjects.

Right ventricular segmentation in cardiac MRI with moving mesh correspondences

This study investigates automatic propagation of the right ventricle (RV) endocardial and epicardial boundaries in 4D (3D+time) magnetic resonance imaging (MRI) sequences. Based on a moving mesh (or grid generation) framework, the proposed algorithm detects the endocardium and epicardium within each cardiac phase via point-to-point correspondences. The proposed method has the following advantages over prior RV segmentation works: (1) it removes the need for a time-consuming, manually built training set; (2) it does not make prior assumptions as to the intensity distributions or shape; (3) it provides a sequence of corresponding points over time, a comprehensive input that can be very useful in cardiac applications other than segmentation, e.g., regional wall motion analysis; and (4) it is more flexible for congenital heart disease where the RV undergoes high variations in shape. Furthermore, the proposed method allows comprehensive RV volumetric analysis over the complete cardiac cycle as well as automatic detections of end-systolic and end-diastolic phases because it provides a segmentation for each time step. Evaluated quantitatively over the 48-subject data set of the MICCAI 2012 RV segmentation challenge, the proposed method yielded an average Dice score of 0.84±0.11 for the epicardium and 0.79±0.17 for the endocardium. Further, quantitative evaluations of the proposed approach in comparisons to manual contours over 23 infant hypoplastic left heart syndrome patients yielded a Dice score of 0.82±0.14, which demonstrates the robustness of the algorithm.

Tagged MRI based cardiac motion modeling and toxicity evaluation in breast cancer radiotherapy.

Recent research showed radiation for breast cancer can increase heart risks (1, 2). In Ref. (2), it has been noted that for every Gy of radiation a women’s heart risk rises 7.4%. However, the correlation between radiation dose and heart tissue damage is still an open problem. A more accurate model of heart damage will significantly improve the heart safety for patients underwent radiotherapy. Modern radiation treatment planning systems (TPS) use computed tomography (CT) images for dose calculation and evaluation. For evaluation of heart toxicity from radiotherapy, the dose-volume histogram (DVH), which is generated by overlying radiation dose distribution on heart delineations in CT images, is widely used. However, there are three major factors that deteriorate the accuracy of TPS-calculated heart dose distribution. First conventional CT is a fundamentally static imaging modality without the capability to capture and depict the cardiac motion. Instead, heart is usually blurred in CT images due to the motion artifacts. Second, without special contrast dye, CT provides limited contrast between blood in heart chambers and the surrounding myocardium. The heart region in TPS is actually a mixture of myocardium and blood, although only the radiation dose to the myocardium is accountable for heart risks. Finally, there is significant intra- and inter-fractional heart motion. As heart beats involuntarily during and between radiation treatments, myocardium deforms and moves non-rigidly against the fixed radiation beam so that the static dose distribution calculated in CT based TPS does not reflect the accurate radiation dose distribution in heart. There is also concern on the choice of the heart function for the evaluation of radiation damage. Based on radiation beam geometry, only part of the heart will receive clinically significant level of radiation during breast cancer treatment. It is possible that the global heart function remains stable temporarily while cells in the irradiated part of the myocardium lose part or all of their functions. In this case, regional heart function, which can be derived from regional heart wall motion and strain analysis, is a better indication of heart damage corresponding to radiation dose. Although cardiac MRI is widely used in radiology for the diagnosis of heart disease, its application in radiation treatment planning is limited. For multiple reasons, it is not practical to use MRI directly for radiation treatment planning of breast cancer patients. However, via multimodality deformable image registration (DIR) between MRI and CT, MRI images may play a more critical role in the evaluation of the heart damage from whole breast radiation. Tagged MRI (tMRI) (3) is a relatively new imaging protocol that has been implemented in the detection and diagnosis of regional heart functional loss. tMRI methods record regional heart wall motion information as they create identifiable landmark bands (tags) in the myocardium to establish dense point to point correspondence between images. ECG-gated tMRI image sets can be acquired at different phases of the cardiac cycle using the corresponding pulse sequence. The 4D (3D plus time) cardiac motion model can be retrieved by image registration between tMRIs at different phases. In the following sessions, we use tMRI as an example to explain how additional heart function information in MRI is retrieved. It is our objective to demonstrate the additional information retrieved from MRI can help the evaluation and protection of heart risks for breast cancer patients, and we want to discuss the possibility of using MRI to establish a more accurate correlation between regional heart functional loss and radiation dose.

Left ventricular function after recanalization of chronic total occlusion

Dear Editors, We read with great interest the article by Erdogan et al. that was recently published in Clinics (1). In this study, the authors evaluated the role of novel echocardiographic techniques in detecting left ventricular functional recovery after successful percutaneous coronary intervention to treat chronic total occlusion. Their study highlights the benefits of restoring blood flow in symptomatic patients and in patients with detectable ischemia in the territory of the occluded vessel. Although the authors did a great job of providing a broad review of echocardiographic data obtained from a considerable number of patients, there are certain missing points that we wish to emphasize. The authors concluded that the improvements in the strain parameters were more significant in patients with an ejection fraction ≥50% and less significant in patients with diabetes. However, they did not use a multivariate regression analysis to adjust for other potential confounders. If they had performed a regression analysis, the authors would have provided more useful information about the impact of percutaneous coronary intervention on different groups. Without an accurate statistical analysis, it is not possible to draw conclusions about the benefits of this treatment in subgroups such as diabetics or patients with a higher ejection fraction. In previous studies, the duration of the occlusion, collateral circulation, and previous myocardial infarction were found to be predictors of the restoration of systolic function after percutaneous intervention (2-5). None of these parameters was evaluated in this research. In a recent study, the influence of the recanalization of chronic total occlusion on left ventricular function was shown using three-dimensional echocardiography. In that study, left ventricular function improved in patients with rich collateral circulation, but no significant change was found in patients with a previous myocardial infarction. In another study, the recovery of left ventricular function was associated with the transmural extent of the myocardial scar, suggesting the impact of previous infarction (6). Given the heterogeneity of the occluded vessels in the study by Erdogan et al., it would have been valuable to provide additional regional wall motion analyses. In a study by Ermis et al., coronary intervention had a positive impact on both global and regional left ventricular function in patients with chronic coronary artery occlusion (7). In another study, which used magnetic resonance imaging, early and late improvements in regional myocardial function were observed in the territory of the occlusion (6). In conclusion, Erdogan et al. demonstrated the benefits of revascularization for left ventricular function in chronic total occlusion. However, a more detailed history of the patients, additional regional wall motion analyses, and a multivariate regression model would have provided valuable information about selecting appropriate patients for this procedure.

From speckle tracking echocardiography to torsion

Speckle tracking is the latest available technology in echocardiography. However, the technology is still mainly used as a research tool. The potential applications of speckle tracking are many, including cardiac synchronization, regional wall motion analysis, and in the areas of cardiac mechanic studies. This review presents the background theory of speckle tracking echocardiography (STE) and how this technology can be extended to velocity vector analysis, strain, and torsion measurements. The interpretations of these measurements are covered. We also present some potential applications in the critical care setting. Speckle tracking is almost always available in high-end ultrasound machines. The technology has been applied to velocity vector analysis, strain and strain rate measurements, and twist and torsion analysis. Torsion analysis and velocity vector analyses are impossible without using speckle tracking. Speckle tracking-derived strain is superior to tissue Doppler strain because it is angle-independent. A number of studies demonstrated that STE is useful in left and right heart assessments and can be used in assessing preload and afterload. Speckle tracking can be used to measure instantaneous myocardial contractility, strain, and left ventricular torsion. It is still a research tool at present, but shows the promise of being a clinical tool in the future.

DANTE-tagging Cine MRIを用いた心室中隔断面の局所壁運動解析

DANTE-tagging Cine MRIを用いた心室中隔断面の局所壁運動解析

Five-year follow-up of the local autologous transplantation of CD133+ enriched bone marrow cells in patients with myocardial infarction.

The implantation of a CD133+ bone marrow cell population into an ischemic myocardium has emerged as a promising therapeutic modality for myocardial regeneration and restoration of ventricular contractility. While previous studies have documented the short-term safety and efficacy of CD133+ cell transplantation in patients with acute myocardial infarction, there are few reports of long-term follow-up results. Here, we present the results of long-term follow-up of our acute myocardial infarction patients who were treated with intramyocardial injection of CD133+ cells after coronary bypass graft. After five years, 13 patients in the cell transplantation group and 5 patients in the control group underwent safety and efficacy investigations by New York Heart Association classification and two-dimensional echocardiography (2D echo). During the five-year study period, no major cardiac adverse events were reported among patients who received CD133+ stem cells. Regarding efficiency, we observed no statistically significant treatment effects for the echocardiographic parameters [left ventricular end-diastolic and end-systolic volumes, and resting ejection fraction] measured during the follow-up period. However, detailed analysis of regional wall motion revealed an improvement in the Wall Motion Score Index from baseline to the six month follow-up, which was maintained during the follow-up period. Taken together, the long-term results of the present study indicate that transplantation of CD133+ is a safe and feasible procedure; however, we could not show any major benefits in our patients. Thus, this issue needs to be addressed by conducting other studies with more patients.

P3-13-06: Cardiovascular Magentic Resonance Imaging and Radiation-Induced Heart Disease Following Radiotherapy for Breast Cancer.

Abstract Background: Radiotherapy (RT) forms a vital component of treatment for breast cancer, contributing to the increasing number of survivors worldwide. It is known from historical cohorts that breast RT increased the risk of developing heart disease 10 years or more following treatment. It is less certain whether the lower cardiac radiation doses received during modern RT still increase cardiac risk. Cardiovascular Magnetic Resonance (CMR) imaging has the potential to provide early surrogate markers of radiation-induced heart disease that may help predict which women will be at increased risk in the future. Methods: This is a prospective longitudinal imaging study to evaluate CMR findings in a cohort of women receiving adjuvant RT for early breast cancer at the Oxford Cancer Centre. The patients undergo CMR imaging (with gadolinium enhancement and adenosine stress), Doppler echocardiography, blood testing (including BNP and troponin), ECG and clinical examination prior to RT, within 72 hours of completing RT, and at 3 months, 6 months and 5 years following RT. The results of these investigations will be related to cardiac radiation exposure estimated using 3D-dosimetric data obtained by analysis of CT-based RT planning. Recruitment and Provisional Results: As of May 2011, 30 women have been recruited. The women had a mean age of 57.1 years (range = 42.0 to 63.9). All women had left-sided cancer and none received adjuvant cytotoxic chemotherapy. The mean whole heart dose was 1.47 Gray (range = 0.65 to 4.20), the mean left ventricle dose was 2.03 (range = 0.88 to 6.99) and the mean left coronary artery dose was 7.55 Gray (range = 1.50 to 24.59). Preliminary analysis of the first 10 participants showed that all had a normal left ventricular ejection fraction at baseline (mean 76%, range 60–82%) and immediately following RT (mean reduction 3%, p=0.18). None had myocardial oedema as detected by T2-STIR imaging or fibrosis and scarring as demonstrated by late gadolinium enhancement (LGE). Conclusion and Future Plans: Preliminary results suggest that the relatively low heart doses received by the women undergoing modern CT-planned left breast RT at the Oxford Cancer Centre do not result in any cardiovascular abnormality detectable by CMR imaging. Further and updated results will be available for the San Antonio Breast Cancer Symposium. Recruitment will continue until at least 20 women have completed baseline scans and follow-up scans up to 6 months. At this stage a full analysis will be performed including a wider range of CMR endpoints including: - Overall LV systolic function (EF and volumes) - Regional wall motion analysis - T2-weighted imaging (oedema) - T1 and T2 mapping (quantitative T1 and T2 relaxation times) - Tagged myocardial strain analysis - Stress perfusion defects (endothelial/microcapillary damage) - Late gadolinium (LGE) imaging (fibrosis/scarring) Depending on the results of this analysis, recruitment may be expanded to include women with either lower cardiac risk (e.g. with right-sided breast cancer) or higher cardiac risk (e.g. receiving anthracycline chemotherapy). Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-13-06.

Cardiac MRI: evaluation of phonocardiogram-gated cine imaging for the assessment of global und regional left ventricular function in clinical routine

To validate a phonocardiogram (PCG)-gated cine imaging approach for the assessment of left ventricular (LV) function. In this prospective study, cine MR imaging of the LV was performed twice in 79 patients by using retrospectively PCG- and retrospectively ECG-gated cine SSFP sequences at 1.5 T. End-diastolic volumes (EDV), end-systolic volumes (ESV), stroke volumes (SV), ejection fraction (EF), muscle mass (MM), as well as regional wall motion were assessed. Subgroup analyses were performed for patients with valvular defects and for patients with dysrhythmia. PCG-gated imaging was feasible in 75 (95%) patients, ECG-gating in all patients. Excellent correlations were observed for all volumetric parameters (r > 0.98 for all variables analysed). No significant differences were observed for EDV (-0.24 ± 3.14 mL, P = 0.5133), ESV (-0.04 ± 2.36 mL, P = 0.8951), SV (-0.20 ± 3.41 mL, P = 0.6083), EF (-0.16 ± 1.98%, P = 0.4910), or MM (0.31 ± 4.2 g, P = 0.7067) for the entire study cohort, nor for either of the subgroups. PCG- and ECG-gated cine imaging revealed similar results for regional wall motion analyses (115 vs. 119 segments with wall motion abnormalities, P = 0.3652). The present study demonstrates that PCG-gated cine imaging enables accurate assessment of global and regional LV function in the vast majority of patients in clinical routine. Phonocardiogram-gating is an alternative to electrocardiographic-gating in cardiac MR. Phonocardiogram-gated imaging allows reliable assessment of global and regional left-ventricular function. Phonocardiogram-gating is feasible in patients with valvular lesions or cardiac dysrhythmia. Because phonocardiogram-gating is insensitive to magneto-hydrodynamic effects, it is suitable for ultra-high field.

Role of Noninvasive Imaging in the Diagnosis of Cardiac Allograft Vasculopathy

Cardiac allograft vasculopathy (CAV) is common, with a prevalence of 52% at 10 years after transplantation, and represents a leading cause of death beyond the first year, responsible for approximately 15% of deaths annually.1 It is characterized by diffuse and concentric intimal proliferation, typically involving the intramural as well as epicardial coronary arteries. Its diagnosis is difficult to establish clinically because of denervation of the transplanted heart. Consequently, it presents late with silent myocardial infarction, progressive heart failure, or arrhythmic sudden death.2 Screening is therefore required for its early detection. Although coronary intravascular ultrasound (IVUS) is considered the gold-standard technique for detecting the anatomic features of CAV (Table 1), its broad clinical use in this context is limited by cost and lack of widespread expertise, and its evaluation is limited to epicardial vessels.3 Coronary angiography, performed annually or biannually, remains the most common clinical screening method.4 However, because of the diffuse nature of CAV with a lack of normal reference segments and the relatively late occurring luminal narrowing, the sensitivity of angiography is as low as 30% when compared with IVUS (Figure 1).5 As a result, complications frequently occur before disease is evident angiographically.6 Furthermore, angiography is associated with significant albeit uncommon complications (overall complication rate, 7.4/1000 procedures, including rates of 0.65/1000, 1.6/1000, and 0.72/1000 for cerebrovascular accidents, vascular complications, and death, respectively), is disliked by transplant recipients, is costly, and repeated studies are associated with an important cumulative radiation dose.7 View this table: Table 1. Stanford Classification of CAV Severity on IVUS Figure 1. Invasive assessment of cardiac allograft vasculopathy (CAV) in a patient with severe disease, highlighting the limited sensitivity of conventional coronary angiography. Although no left anterior descending (LAD) flow-limiting stenoses are seen on angiography ( A ), intravascular ultrasound ( B ) shows significant intimal thickening, measuring up to …

The Cardiac Atlas Project—an imaging database for computational modeling and statistical atlases of the heart

Motivation: Integrative mathematical and statistical models of cardiac anatomy and physiology can play a vital role in understanding cardiac disease phenotype and planning therapeutic strategies. However, the accuracy and predictive power of such models is dependent upon the breadth and depth of noninvasive imaging datasets. The Cardiac Atlas Project (CAP) has established a large-scale database of cardiac imaging examinations and associated clinical data in order to develop a shareable, web-accessible, structural and functional atlas of the normal and pathological heart for clinical, research and educational purposes. A goal of CAP is to facilitate collaborative statistical analysis of regional heart shape and wall motion and characterize cardiac function among and within population groups.Results: Three main open-source software components were developed: (i) a database with web-interface; (ii) a modeling client for 3D + time visualization and parametric description of shape and motion; and (iii) open data formats for semantic characterization of models and annotations. The database was implemented using a three-tier architecture utilizing MySQL, JBoss and Dcm4chee, in compliance with the DICOM standard to provide compatibility with existing clinical networks and devices. Parts of Dcm4chee were extended to access image specific attributes as search parameters. To date, approximately 3000 de-identified cardiac imaging examinations are available in the database. All software components developed by the CAP are open source and are freely available under the Mozilla Public License Version 1.1 (http://www.mozilla.org/MPL/MPL-1.1.txt).Availability: http://www.cardiacatlas.orgContact: a.young@auckland.ac.nzSupplementary information: Supplementary data are available at Bioinformatics online.

The Dawn of Third-generation Stress Echocardiography?

In this edition of the Journal, Jorge Lowenstein et al. indicate the possible way to third generation stress echocardiography. (1) The authors used three tools together during the realization of the unique stress echo with dipyridamole potentiated with atropine to evaluate three different objectives: the bidimensional echocardiogram (2D echo) for the semiquantitative evaluation of the regional wall motion analysis, supported by the habitual practice, and at the same time qualitative and subjective, colour pulsed Doppler for the evaluation of the coronary reserve in the anterior descending artery (ADA) and the strain 2D for the expected quantitative evaluation of the left ventricle longitudinal function. All this in only one imaging test which is fast, safe, free of radiations, objective and inexpensive and with high diagnostic precision.

Evaluation of Left Ventricular Diastolic Function with Cardiac MR Imaging

Assessment of left ventricular (LV) function with cardiac magnetic resonance (MR) imaging is often limited to evaluation of systolic function, including analysis of regional wall motion, measurement of mass and volume, and estimation of ejection fraction. However, diastolic dysfunction is present in various heart diseases, particularly in heart failure with preserved ejection fraction, which is increasingly prevalent and is associated with a poor prognosis. In daily practice, the assessment of diastolic function is mainly performed with transthoracic echocardiography. Evaluation of diastolic function with cardiac MR imaging is seldom performed in clinical practice. However, basic assessment of LV relaxation and stiffness abnormalities can be achieved with MR imaging by using a combination of left atrium size measurement and phase-contrast evaluation of transmitral flow. In addition, assessment of pulmonary venous flow and the LV filling curve can also be performed. Furthermore, MR imaging with late gadolinium enhancement sequences provides insight into the extent of myocardial fibrosis, which strongly influences LV stiffness. Finally, phase-contrast evaluation of tissue velocities, myocardial tagging, MR spectroscopy, and MR elastography are promising tools for a better understanding of LV diastolic function but require further evaluation.