Semiautomatic three-dimensional CT ventricular volumetry in patients with congenital heart disease: agreement between two methods with different user interaction

To assess agreement between two semi-automatic, three-dimensional (3D) computed tomography (CT) ventricular volumetry methods with different user interactions in patients with congenital heart disease. In 30 patients with congenital heart disease (median age 8 years, range 5 days–33 years; 20 men), dual-source, multi-section, electrocardiography-synchronized cardiac CT was obtained at the end-systolic (n = 22) and/or end-diastolic (n = 28) phase. Nineteen left ventricle end-systolic (LV ESV), 28 left ventricle end-diastolic (LV EDV), 22 right ventricle end-systolic (RV ESV), and 28 right ventricle end-diastolic volumes (RV EDV) were successfully calculated using two semi-automatic, 3D segmentation methods with different user interactions (high in method 1, low in method 2). The calculated ventricular volumes of the two methods were compared and correlated. A P value <0.05 was considered statistically significant. LV ESV (35.95 ± 23.49 ml), LV EDV (88.76 ± 61.83 ml), and RV ESV (46.87 ± 47.39 ml) measured by method 2 were slightly but significantly smaller than those measured by method 1 (41.25 ± 26.94 ml, 92.20 ± 62.69 ml, 53.61 ± 50.08 ml for LV ESV, LV EDV, and RV ESV, respectively; P ≤ 0.02). In contrast, no statistically significant difference in RV EDV (122.57 ± 88.57 ml in method 1, 123.83 ± 89.89 ml in method 2; P = 0.36) was found between the two methods. All ventricular volumes showed very high correlation (R = 0.978, 0.993, 0.985, 0.997 for LV ESV, LV EDV, RV ESV, and RV EDV, respectively; P < 0.001) between the two methods. In patients with congenital heart disease, 3D CT ventricular volumetry shows good agreement and high correlation between the two methods, but method 2 tends to slightly underestimate LV ESV, LV EDV, and RV ESV.     

The washout rate of <Superscript>123</Superscript>I-BMIPP and the evolution of left ventricular function in patients with successfully reperfused ST-segment elevation myocardial infarction: comparisons with the echocardiography

The evolution of the oxidative metabolism of ¹¹C acetate parallels the recovery of left ventricular (LV) contraction following acute myocardial infarction (AMI). This study was designed to unravel, for the first time, the impact of the global washout rate (WR) of ¹²³I-β-methyl-p-iodophenylpentadecanoic acid (BMIPP) on the recovery of LV function following AMI, as evidenced from conventional echocardiography. Twenty consecutive patients (age: 58 ± 13 years; 16 males and 4 females) with ST-segment elevation myocardial infarction (STEMI) were enrolled and all of them underwent successful percutaneous coronary intervention (PCI). ¹²³I-BMIPP cardiac scintigraphy was performed at 7 ± 3 days after admission. The WR was calculated from the polar map and the regional BMIPP defect score was calculated using a 17 segment model. Echocardiography was performed within 24 h of admission and at 3 months to record the ejection fraction (EF), the wall motion score index (WMSI), the ratio of the mitral inflow velocity to the early diastolic velocity (E/E′) and the myocardial performance index (MPI). The mean global WR of the BMIPP was 22.12 ± 7.22%, and it was significantly correlated with the improvement of the WMSI (r = 0.61, P < 0.004). However, the relative changes of the EF, E/E′ and MPI were not correlated with the WR. The BMIPP defect score (18 ± 10) was significantly correlated with the WMSI on admission (r = 0.74, P = 0.0002), but the defect score was not correlated with the relative changes of any of the echocardiographic parameters. We proved that the WR of the BMIPP is a promising indicator of improvement of the LV wall motion (WMSI) following ST-segment elevation myocardial infarction and successful reperfusion.     

整体长轴收缩期峰值应变率指标评价心肌梗死患者左室收缩功能

目的 探讨整体长轴收缩期峰值应变率指标在评价心肌梗死患者左室整体收缩功能中的应用价值.方法 对14例心肌梗死患者与20例健康对照者,采集心尖两腔、四腔及左室长轴切面二维超声图像,应用VVI技术测量左室各节段收缩期长轴峰值应变率(SRs)并取平均值得出左室整体长轴收缩期峰值应变率(GSRs).以常规二维超声心动图评价左室壁节段运动,计算室壁运动积分指数(WMSI),并应用Simpson双平面法计算左室射血分数(LVEF).应用脉冲波组织多普勒显像(PDTI)技术测量并计算二尖瓣环平均收缩期峰值速度(Sm).比较两组间各指标,评价GSRs指标与WMSI指标、Sm指标及LVEF指标的关系.结果 心肌梗死患者组及正常对照组GSRs、WMSI、Sm及LVEF分别为(-0.57±0.21)%和(-1.02±0.09)%、(1.90±0.80)和(1.10±0.30)、(6.20±1.50)cm/s和(9.80±1.30)cm/s、(32.90±7.10)%和(65.50±5.70)%,差异均有统计学意义(P<0.05),且GSRs与WMSI、Sm及LVEF均呈高度相关(r=0.97,-0.98,-0.93, P<0.0001).结论 GSRs是客观评价左室整体收缩功能的新指标.     

实时三维超声心动图对比评价正常右心室及左心室功能

目的 观察利用实时三维超声心动图(RT-3DE)评估、比较成年人正常心脏左右心室的可行性,并探讨左右心室之间的关系.方法 应用RT-3DE全容积成像采集58名心脏正常成年人的心脏三维数据,在TomTec工作站中分析获得右心室舒张末期容积(EDV)、收缩末期容积(ESV)、每搏输出量(SV)和射血分数(EF);在Qlab工作站中分析获得左心室舒张末期容积(EDV)、收缩末期容积(ESV)、每搏输出量(SV)和射血分数(EF).结果 右心室EDV[(85.84±20.82)ml]、ESV[(41.87士10.48)ml]分别大于左心室EDV[(69.37士17.83)ml]、ESV[(26.46±8.26) ml](P均＜0.001),而右心室EF[(50.94士5.57)％]小于左心室EF[(61.97±6.48)％,P＜0.001].左心室SV[(42.91±11.72) ml]与右心室SV[(43.96±12.15) ml]差异无统计学意义(P=0.273).左右心室的对应参数均有相关性.结论 RT-3DE是评估左右心室容积和功能的可行方法,且其相应参数在左右心室间是相关的.     

Function of remote non-infarcted myocardium after STEMI: analysis with cardiovascular magnetic resonance

To evaluate remote myocardial function after ST-elevation myocardial infarction (STEMI) and the impact of infarct size (IS) using cardiovascular magnetic resonance (CMR). 161 patients and 15 controls underwent CMR at 1st week and 6th month after STEMI. Using the 17-segments model, segments were categorized into infarcted, adjacent and remote myocardium. Relative systolic wall thickening (SWT, %) was assessed using the centerline method. IS (% of left ventricular mass) was determined in late enhancement imaging. Overall, in remote myocardium, SWT was comparable (83 ± 32) to controls (77 ± 25, P = .5) and did not increase significantly (P = .2) at the 6th month (88 ± 35, P = .3 vs. control). When IS was categorized into tertiles (<13.6%, (n = 49), 13.7–28.2%, (n = 60), >28.2%, (n = 52)), SWT in the remote area at the 1st week was not different from controls, regardless of infarct size (p between .2 and .8 for all tertiles). At 6 months, SWT was larger compared to controls only in small infarctions (98 ± 34 vs. 77 ± 25, P = .03). In medium and large infarctions there was no difference in SWT of the remote area compared to controls (87 ± 33 and 79 ± 34, P = .3 and P = .09) and there was no significant increase at 6 months (P between .2 and .9). In remote myocardium there was no difference in contractility compared to controls after STEMI. After 6 month a slight hypercontractility can only be observed in small infarctions. In medium and large infarctions no difference of SWT in remote myocardium compared to controls can be observed.     

Comparison of magnetic resonance imaging findings in non-ST-segment elevation versus ST-segment elevation myocardial infarction patients undergoing early invasive intervention

To define causes and pathological mechanisms underlying differences in clinical outcomes, we compared the findings of contrast-enhanced magnetic resonance imaging (CE-MRI) between ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI). In 168 patients undergoing early invasive intervention for STEMI (n = 113) and NSTEMI (n = 55), CE-MRI was performed a median of 6 days after the index event. Infarct size was measured on delayed-enhancement imaging, and area at risk (AAR) was quantified on T2-weighted images. The median infarct size was significantly smaller in the NSTEMI group than in the STEMI group (10.7% [5.6–18.1] vs. 19.2% [10.3–30.7], P < 0.001). Although there was a trend toward a greater myocardial salvage index ([AAR ? infarct size] × 100/AAR) in the NSTEMI group compared to the STEMI group (48.2 [30.4–66.8] vs. 40.5 [24.8–53.5], P = 0.056), myocardial salvage index was similar between the groups in patients with anterior infarction (39.6 [20.0–54.9] vs. 35.5 [23.2–53.4], P = 0.96). The NSTEMI group also had a significantly lower extent of microvascular obstruction and a smaller number of segments with >75% of infarct transmurality relative to the STEMI group (0% [0–0.6] vs. 0.9% [0–2.3], P < 0.001 and 3.0 ± 2.3 vs. 4.6 ± 2.9, P = 0.001, respectively). Myocardial hemorrhage was detected less frequently in the NSTEMI group than the STEMI group (22.6% vs. 43.8%, P = 0.029). In the multivariate analysis, baseline Thrombolysis In Myocardial Infarction flow grade 3 and hemorrhagic infarction were closely associated with ST-segment elevation (OR 0.32, 95% CI 0.13–0.81, P = 0.017; OR 5.66, 95% CI 1.77–18.12, P = 0.003, respectively). In conclusion, in vivo pathophysiological differences revealed by CE-MRI assessment include more favorable infarct size, AAR, myocardial salvage and reperfusion injury in patients with NSTEMI compared to those with STEMI undergoing early invasive intervention.     

Relationship between atrial septal aneurysms and atrial electromechanical delay

Atrial septal aneurysm (ASA) is a saccular deformity located in the atrial septum. Atrial arrhythmias are common in patients with ASA. Atrial electromechanical delay (AEMD) can be used to evaluate development of atrial arrhythmias in various settings. The aim of the study was to investigate the relationship between ASA, cardiac arrhythmias and AEMD. Seventy patients with ASA served as the study group (30 men; mean age, 33.6 ± 10.9 years) and 70 healthy volunteers served as the control group (34 men; mean age, 31.4 ± 7.8 years). ASAs were diagnosed by transthoracic echocardiography based on the criteria of a minimal aneurysmal base of ??15 mm; and an excursion of ??10 mm. Inter-AEMD and intra-AEMDs of both atrium were measured from parameters of tissue Doppler imaging. There was no significant difference between the study and control groups in terms of age, gender, left atrium diameter, and left ventricular ejection fraction. Inter-AEMD (50.7 ± 22.5 ms vs. 36.9 ± 12.0 ms) and intra-left AEMD (44.6 ± 17.4 ms vs. 30.7 ± 11.6 ms) were significantly higher in patients with ASA with respect to control group. Inter-AEMD (63.6 ± 20.1 ms vs. 45.1 ± 21.5 ms, P = 0.001), intra-left AEMD (55.3 ± 15.6 ms vs. 40.1 ± 16.2 ms, P = 0.001), diameter of the ASA (19.9 ± 3.6 mm vs. 17.1 ± 2.7 mm, P = 0.001) and P wave dispersion (18.5 ± 6.7 ms vs. 11.8 ± 7.3 ms, P = 0.001) were significantly greater in the subgroup with arrhythmias compared to the subgroup without arrhythmias. Inter-AEMD and intra-left AEMD were found to be significantly prolonged in patients with ASA. Being a non-invasive, inexpensive and simple technique AEMD may provide significant contributions to assess the risk for paroxysmal supraventricular arrhythmia in patients with ASA.     

三维面积应变评价高血压患者左心室心肌收缩功能早期变化

目的 应用三维斑点追踪成像（3D-STE）技术评价原发性高血压患者早期左心室心肌收缩功能改变情况。方法 对40例未经药物治疗的原发性高血压患者（高血压组）及40名健康志愿者（对照组）行常规二维超声心动图和3D-STE,测量并比较两组常规超声心动图指标包括舒张末期室间隔厚度（IVSTd）、舒张末期左心室后壁厚度（LVPWTd）、左心室舒张末期内径（LVEDd）、相对室壁厚度（RWT）、二维左心室心肌质量指数（2D-LVMi）、二维左心室射血分数（2D-LVEF）、舒张末期左心室容积（EDV）、收缩末期左心室容积（ESV）,以及3D-STE指标包括左心室三维射血分数（3D-LVEF）、左心室球形指数（SPI）、三维左心室心肌质量指数（3D-LVMi）及左心室整体面积应变（GAS）差异;采用Pearson相关分析检验GAS与各指标间相关性。结果 两组患者IVSTd、LVPWTd、LVEDd、RWT、2D-LVMi、2D-LVEF、EDV、ESV、3D-LVEF和SPI差异均无统计学差异（P均>0.05）;高血压组3D-LVMi高于对照组[(104.20±7.94) vs (92.85±6.92),P<0.05),GAS低于对照组[(-25.53±3.79) vs (-31.43±3.13),P<0.05]。GAS与3D-EF呈负相关（r=-0.78,P<0.05）,与3D-LVMi、收缩压及舒张压呈正相关（r=0.81、0.60、0.50,P<0.05）。结论 原发性高血压患者早期左心室构型未发生明显变化时,左心室心肌收缩功能已经减低,可通过3D-STE中GAS进行评价。     

Ventricular tachyarrhythmias in patients receiving an implantable cardioverter-defibrillator for primary versus secondary prophylaxis indications

Introduction: Data on the mechanisms of sudden cardiac death are limited and may be biased by delays in rhythm recording and selection bias in survivors. As a result, the relative contributions of monomorphic ventricular tachycardia (VT) (cycle length [CL] > 260 ms), monomorphic fast VT (FVT) (CL ≤ 260 ms), and polymorphic VT (PMVT)/ventricular fibrillation (VF) have not been well characterized nor compared in patients with and without prior arrhythmic events. Methods: A retrospective cohort study of implantable cardioverter‐defibrillator (ICD) recipients with primary or secondary implant indications was used to evaluate intracardiac electrograms (EGMs) for the first spontaneous VT/VF resulting in appropriate ICD therapy. EGMs were categorized into VT, FVT, and PMVT/VF based on CL and morphologic criteria. Results: Of 616 implants, 145 patients (58 [40%] primary indications) received appropriate ICD therapy for VT/VF over mean follow‐up of 3.8 ± 3.2 years. Primary implants had more diabetes (28% vs 12%; P = 0.02) and less antiarrhythmic use (15% vs 33%; P = 0.02). In those patients with spontaneous arrhythmia, PMVT/VF occurred in 20.7% of primary versus 21.8% of secondary implants, FVT in 19.0% versus 21.8%, and VT in 60.3% versus 56.4%, respectively (P = 0.88). Spontaneous VT CL was similar regardless of implant indication (284 ± 56 [primary] vs 286 ± 67 ms [secondary]; P = 0.92). Conclusions: Monomorphic VT is the most common cause of appropriate ICD therapy regardless of implant indication. These results provide insight into the mechanisms of sudden cardiac death and have implications for the use of interventions designed to limit ICD shocks. (PACE 2011; 34:571–576)     

Global longitudinal strain and left atrial volume index improve prediction of appropriate implantable cardioverter defibrillator therapy in hypertrophic cardiomyopathy patients

Accurate predictors of appropriate implantable cardioverter defibrillator (ICD) therapy in hypertrophic cardiomyopathy (HCM) patients are lacking. Both left atrial volume index (LAVI) and global longitudinal strain (GLS) have been proposed as prognostic markers in HCM patients. The specific value of LAVI and GLS to predict appropriate ICD therapy in high-risk HCM patients was studied. LAVI and 2-dimensional speckle tracking-derived GLS were assessed in 92 HCM patients undergoing ICD implantation (69 % men, mean age 50 ± 14 years). During long-term follow-up, appropriate ICD therapies, defined as antitachycardia pacing and/or shock for ventricular arrhythmia, were recorded. Appropriate ICD therapy occurred in 21 patients (23 %) during a median follow-up of 4.7 (2.2–8.2) years. Multivariate analysis revealed LAVI (p = 0.03) and GLS (p = 0.04) to be independent predictors of appropriate ICD therapy. Both LAVI and GLS showed higher accuracy to predict appropriate ICD therapy compared to presence of ≥1 conventional sudden cardiac death (SCD) risk factor(s) [area under the curve 0.76 (95 % CI 0.65–0.87) and 0.65 (95 % CI 0.54–0.77) versus 0.52 (95 % CI 0.43–0.58) respectively, p < 0.001]. No patient with both LAVI <34 mL/m² and GLS <?14 % experienced appropriate ICD therapy. Assessment of both LAVI and GLS on top of conventional SCD risk factors provided incremental clinical predictive value for appropriate ICD therapy, as shown by likelihood ratio test (p < 0.001) and integrated discrimination improvement index (0.17, p < 0.001). LAVI and GLS provide high negative predictive value for appropriate ICD therapy in high-risk HCM patients. Additionally to conventional SCD risk factors, both parameters may be useful to optimize criteria and timing for ICD implantation in these patients.     

Implantable Cardioverter Defibrillator Therapy for Prevention of Sudden Cardiac Death in Children in The Netherlands

Introduction: Implantable cardioverter defibrillator (ICD) therapy is increasingly used in children. The purpose of this multicenter study is to evaluate mid‐term clinical outcome and to identify predictors for device discharge in pediatric ICD recipients. Methods and Results: From 1995 to 2006, 45 patients in The Netherlands under the age of 18 years received an ICD. Mean age at implantation was 10.8 ± 5.2 years. Primary prevention (N = 22) and secondary prevention (N = 23) were equally distributed. Underlying cardiac disorders were primary electrical disease (55%), cardiomyopathy (20%), and congenital heart disease (17%). The follow‐up was 44 ± 32.9 months. Three patients (7%) died and one patient (2%) underwent heart transplantation. ICD‐related complications occurred in eight patients (17%), seven of whom had lead‐related complications. Fourteen patients (31%) received appropriate ICD shocks; 12 patients (27%) received inappropriate ICD shocks. Fifty‐five percent of 22 ICD recipients under the age of 12 years received appropriate shocks, which was higher as compared with 9% of 23 older ICD recipients (P = 0.003). Although the incidence of appropriate shocks in the present study was larger in secondary prevention (9/23; 39%) as compared with primary prevention (5/22; 23%), this difference did not reach significance. Conclusions: In our population of patients, children <12 years of age had more appropriate shocks than patients 13–18 years. The complication rate is low, and is mainly lead related. (PACE 2010; 33:179–185)     

Assessment of right ventricular function with 320-slice volume cardiac CT: comparison with cardiac magnetic resonance imaging

To evaluate the accuracy and feasibility of right ventricular function parameters measurement using 320-slice volume cardiac CT. Retrospective analysis of 50 consecutive patients (23 men, 27 women) with suspected pulmonary diseases was performed in electrocardiogram (ECG)-gated cardiac CT and cardiac magnetic resonance (CMR). Parameters including right ventricular end-diastolic volume (RVEDV), right ventricular end- systolic volume (RVESV), right ventricular stroke volume (RVSV), right ventricular cardiac output (RVCO), and right ventricular ejection fraction (RVEF) were semi-automatically and separately calculated from both CT and CMR data. Significant difference between measurements was measured by paired t test and two-variable linear regression analysis with Pearson’s correlation coefficient. Bland–Altman analysis was performed in each pair of parameters. There was little variability between the measurements by the two observers (kappa = 0.895–0.980, P < 0.05). There was good correlation between all parameters obtained by CT and CMR (P < 0.001): RVEDV (108.5 ± 21.9 ml, 113.5 ± 24.8 ml, r = 0.944), RVESV (69.8 ± 33.4 ml, 73.2 ± 35.4 ml, r = 0.972), RVSV (39.0 ± 13.2 ml, 40.2 ± 13.3 ml, r = 0.977), RVCO (2.6 ± 0.7 l, 2.6 ± 0.7 l. r = 0.958), RVEF (38.8 ± 19.1 %, 39.1 ± 19.3 %, r = 0.990), and there was no significant difference between CT and CMR measurements in RVEF (n = 50, t = ?0.677, P > 0.05). 320-slice volume cardiac CT is an accurate non-invasive technique to evaluate RV function.     

Assessment of microembolization associated with revascularization in acute myocardial infarction: MDCT cardiac perfusion and function study

To use multi-detector computed tomography (MDCT) for assessing the effects of coronary microemboli on pre-existing acute myocardial infarct (AMI) and to compare this pathology to LAD microembolization and occlusion/reperfusion. An angioplasty balloon catheter was placed in the LAD coronary artery of pigs under X-ray guidance. Four animals served as controls without intervention (group A) and an additional 24 animals (8/group) were subjected to microembolization (group B), occlusion/reperfusion (group C) or combination of the two insults (group D). MDCT was used to assess perfusion, LV function and viability. At postmortem, the LV sections were stained with hematoxylin/eosin and triphenyltetrazolium chloride (TTC). Dynamic perfusion and helical cine MDCT demonstrated decline in regional LV perfusion and function, respectively, after all interventions. MDCT showed significant differences in ejection fraction between groups: A = 57.5 ± 4.7 %, B = 40.3 ± 0.5 % P < 0.05, C = 34.9 ± 1.3 % P < 0.05 and D = 30.7 ± 1.2 % P < 0.05, while viability MDCT demonstrated differences in enhancement patterns and extents of damage between the groups (B = 9.1 ± 0.4 % LV mass, C = 11.9 ± 0.7 % and D = 16.2 ± 1.2 %, P < 0.05) and extent of microvascular obstruction (MVO) (group C = 3.2 ± 1.0 % LV mass versus D = 5.2 ± 0.7 %, P < 0.01). DE-MDCT overestimated all types of myocardial damage compared with TTC, but showed a close correlation (r > 0.7). Microscopic examination confirmed the presence of patchy and contiguous necrosis, MVO, edema and calcium deposits. Dynamic and helical cine MDCT imaging can grade LV dysfunction and perfusion deficit, respectively. DE-MDCT demonstrated a large and persistent MVO zone after microembolization of pre-existing AMI. Furthermore, it has the potential to visualize patchy microinfarct, detect perfusion deficits and dysfunction at the border zone after microembolization of pre-existing AMI.     

Effects of distal protection on left ventricular function in acute anterior myocardial infarction: a Doppler echocardiographic study

Whether distal protection devices (DPDs) during percutaneous coronary intervention (PCI) can improve myocardial function in patients with acute myocardial infarction (AMI) is still under debate. Using tissue Doppler imaging (TDI), we evaluate the global and regional left ventricular systolic and diastolic functions in patients with anterior AMI using DPDs compared with conventional PCI. Ninety-six patients with anterior AMI were randomly assigned to either PCI with DPDs (DPD, n = 46) or traditional PCI (control, n = 50) groups. At the 3- and 6-month follow-ups, the DPD group had a higher left ventricular ejection fraction than the control group (51.6 ± 3.6 vs. 49.3 ± 5.3% and 53.0 ± 3.7 vs. 50.8 ± 5.2%, respectively; both P < 0.05). Moreover, peak systolic (S _a) and early diastolic (E _a) mitral annular velocities obtained by TDI were significantly higher in the DPD group than in the control group (S _a: 7.57 ± 0.53 vs. 7.12 ± 0.62 cm/s and 7.71 ± 0.63 vs. 7.32 ± 0.59 cm/s; E _a: 7.23 ± 0.78 vs. 6.89 ± 0.86 cm/s and 7.49 ± 0.69 vs. 7.04 ± 0.85 cm/s, respectively; all P < 0.05). However, systolic and diastolic regional myocardial velocities significantly improved in the DPD group from the 1-month follow-up compared with those in the control group (all P < 0.05). Patients who received treatment with DPDs experienced enhanced improvement of cardiac function. Thus, anterior AMI patients can benefit from DPDs during PCI.     

Differentiation of transmural and nontransmural infarction using speckle tracking imaging to assess endocardial and epicardial torsion after revascularization

Assessment of transmural extent (TME) of necrosis after acute myocardial infarction (MI) remains a major problem in clinical practice. The study sought to determine whether speckle tracking imaging (STI) could differentiate transmural from nontransmural acute MI by assessment of endocardial and epicardial torsion. TME of infarct was measured by contrast-enhanced magnetic resonance imaging. Patients were divided into two groups according to TME (transmural MI group [TME ≥ 50 %, n = 36] and nontransmural MI group [TME < 50 %, n = 35]). As a control group, 30 subjects without evidence of structural heart disease were included. Conventional echocardiography and STI were done in controls and patients before and 1 month after percutaneous coronary intervention. Compared with control subjects, endocardial and epicardial torsion in patients with transmural and nontransmural MI were all extremely decreased (all P < 0.01). One month after percutaneous coronary intervention, there was no significant increase in endocardial and epicardial torsion in transmural MI patients. However, apical rotation and left ventricular torsion resumed slightly but significantly in the epicardium (but not endocardium) in patient with nontransmural MI (3.11 ± 0.81 vs. 4.37 ± 1.15°, P < 0.01; 3.69 ± 1.07 vs. 5.52 ± 1.89°, P < 0.01, respectively). The combined evaluation of endocardial and epicardial torsion by STI may be used to differentiate transmural from nontransmural MI after revascularization.     

[68Ga]-Albumin-PET in the Monitoring of Left Ventricular Function in Murine Models of Ischemic and Dilated Cardiomyopathy: Comparison with Cardiac MRI

Purpose

The purpose of this study is to evaluate left ventricular functional parameters in healthy mice and in different murine models of cardiomyopathy with the novel blood pool (BP) positron emission tomography (PET) tracer [⁶⁸Ga]-albumin.

Procedures

ECG-gated microPET examinations were obtained in healthy mice, and mice with dilative (DCM) and ischemic cardiomyopathy (ICM) using the novel BP tracer [⁶⁸Ga]-albumin (Alb_BP), as well as [¹⁸F]-FDG microPET. Cine-magnetic resonance imaging (MRI) examination performed on a clinical 1.5-T MRI provided the reference standard measurements.

Results

When considering the combined group of healthy controls, DCM and ICM Alb_BP-PET significantly overestimated the magnitudes of EDV (Alb_BP, 181?±?86 μl; cine-MRI, 125?±?80 μl; P?<?0.001) and ESV (Alb_BP, 136?±?92 μl; cine-MRI, 96?±?77 μl; P?<?0.001), whereas the EF (Alb_BP, 31?±?16 %; cine-MRI, 33?±?21 %; P?=?0.910) matched closely to cine-MRI results, as did findings with [¹⁸F]-FDG. High correlations were found between the measured cardiac parameters (EDV: R?=?0.978, ESV: R?=?0.989, and LVEF: R?=?0.992).

Conclusions

Measuring left ventricular function in mice with [⁶⁸Ga]-albumin BP PET is feasible and showed a high correlation compared to cine-MRI, which was used as a reference standard.     

Impact of white blood cell count on myocardial salvage,infarct size,and clinical outcomes in patients undergoing primary percutaneous coronary intervention for ST-segment elevation myocardial infarction: a magnetic resonance imaging study

We sought to determine the relationship between white blood cell count (WBCc) and infarct size assessed by cardiovascular magnetic resonance imaging (CMR) in patients undergoing primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI). In 198 patients undergoing primary PCI for STEMI, WBCc was measured upon arrival and CMR was performed a median of 7 days after the index event. Infarct size was measured on delayed enhancement imaging and the area at risk (AAR) was quantified on T2-weighted images. Baseline characteristics were not significantly different between the high WBCc group (>11,000/mm³, n = 91) and low WBCc group (≤11,000/mm³, n = 107). The median infarct size was larger in the high WBCc group than in the low WBCc group [22.0 % (16.7–33.9) vs. 14.7 % (8.5–24.7), p < 0.01]. Compared with the low WBCc group, the high WBCc group had a greater extent of AAR and a smaller myocardial salvage index [MSI = (AAR?infarct size)/AAR × 100]. The major adverse cardiovascular events (MACE) including cardiac death, nonfatal reinfarction, and rehospitalization for congestive heart failure at 12-month occurred more frequently in the high WBCc group (12.1 vs. 0.9 %, p < 0.01). In multivariate analysis, high WBCc significantly increased the risk of a large infarct (OR 3.04 95 % CI 1.65–5.61, p < 0.01), a low MSI (OR 2.08, 95 % CI 1.13–3.86, p = 0.02), and 1-year MACE (OR 16.0, 95 % CI 1.89–134.5, p = 0.01). In patients undergoing primary PCI for STEMI, an elevated baseline WBCc is associated with less salvaged myocardium, larger infarct size and poorer clinical outcomes.     

Assessment of global function of left ventricle with dual-source CT in patients with severe arrhythmia: a comparison with the use of two-dimensional transthoracic echocardiography

To evaluate the agreement between dual-source computed tomography (DSCT) and two-dimensional transthoracic echocardiography (2D-TTE) with respect to the assessment of global left ventricular (LV) function in patients with severe arrhythmia. With 2D-TTE serving as the reference method, we performed both DSCT and 2D-TTE, at an interval of less than 2 days, in 54 patients with severe arrhythmia (average heart rate difference >30 beats per min) before open heart surgery for evaluation of valvular heart disease (VHD) and coronary artery disease. DSCT was performed using retrospective electrocardiography (ECG) without dose modulation. Ten phases of the cardiac cycle were analyzed for identification of end-diastolic and end-systolic phases with ECG-editing. Pearson’s correlation coefficient (r) and Bland–Altman analysis were used to determine agreement for parameters of LV global function. Correlation between DSCT and 2D-TTE measurements was good or excellent in terms of the values of the LV ejection fraction (51.0 ± 11.4% vs. 55.8 ± 11.6%; r = 0.8), LV end-diastolic volume (179.5 ± 98.6 ml vs. 152.1 ± 73.8 ml; r = 0.95), LV end-systolic volume (90.7 ± 60.7 ml vs. 69.1 ± 46.8 ml; r = 0.90), and LV stroke volume (89.0 ± 48.1 ml vs. 82.9 ± 37.3 ml; r = 0.89). Left ventricular ejection fraction measured using DSCT was less than that measured using 2D-TTE by an average of ?4.8 ± 7.3%. Dual-source CT with ECG editing can provide results comparable to those of 2D-TTE for assessment of LV global function in patients with severe arrhythmia.     

Effect of intramyocardial bone marrow-derived mononuclear cell injection on cardiac sympathetic innervation in patients with chronic myocardial ischemia

Intramyocardial bone marrow cell injection has been associated with improvements in myocardial perfusion and left ventricular function. The current substudy of a randomized, placebo-controlled, double-blinded study, investigated the effect of intramyocardial bone marrow cell injection on myocardial sympathetic innervation in patients with chronic myocardial ischemia. In a total of 16 patients (64 ± 8 years, 13 men), early and late iodine-123 metaiodobenzylguanidine (MIBG) imaging was performed before and 3 months after intramyocardial bone marrow cell injection. No improvements were observed in global early H/M ratio (P = 0.40), late H/M ratio (P = 0.43) and cardiac washout rate (P = 0.98). However, late 123-I MIBG SPECT defect score showed a trend to improvement in the bone marrow cell group (from 31.0 ± 7.1 to 28.1 ± 14.9) as compared to the placebo group (from 33.6 ± 8.5 to 34.5 ± 9.8, P = 0.055 between groups). This trend was mainly driven by a substantial improvement in three bone marrow cell-treated patients, which all had diabetes and severe MIBG defects. In these patients, the extent and severity of MIBG defects improved substantially independent of myocardial perfusion and cell injection sites. The present study does not demonstrate improvements in global cardiac sympathetic nerve innervation after intramyocardial bone marrow cell injection in patients with chronic myocardial ischemia. However, regional analysis of sympathetic nerve innervation reveals improvements in three diabetic patients independent of myocardial perfusion, suggestive of a therapeutic effect on diabetic cardiac sympathetic dysinnervation.     

Left atrial functional reservoir: predictive value for outcome of catheter ablation in paroxysmal atrial fibrillation

Left arial (LA) function, defined according to conduit, reservoir and booster functions, is closely linked to left ventricular (LV) mechanics, particularly during diastole. Right ventricular pacing (RVP) is thought to impair LA diastolic restoring forces through alteration of ventricular activation. The aim of this study was to determine whether the LA functional reservoir estimated as the change in mean LA ejection fraction (EF) immediately after RVP, and for the second and for the third beats after RVP, predicts clinical outcome in patients with paroxysmal atrial fibrillation (AF) who have undergone catheter ablation (CA). Data from 155 patients with paroxysmal AF (56.0 ± 10.6 years, M:F = 114:41) were analyzed. All patients underwent LA angiography during RVP. LA EFs were measured at the immediate first (LA EF₁), second (LA EF₂) and third beats (LA EF₃) after RVP, using a right anterior oblique 30° view. During follow-up, AF recurred in 35 patients (22.6 %). Mean LA EF₁ was 37.9 ± .8 % in the AF recurrence group and 48.0 ± 8.6 % in the non-recurrence group (P < 0.001). Mean LA EF₂ and LA EF₃ were also lower in the AF recurrence group than in the non-recurrence group (P < 0.001, respectively). Mean percent changes from LA EF₂ to LA EF₃ were ?0.4 ± 3.4 in the AF recurrence group and 5.2 ± 4.9 in the non-recurrence group (P = 0.041). The change in mean EF from LA EF₁ to LA EF₃ in the non-recurrence group was significantly greater than in the recurrence group (P = 0.001). Cox regression analysis showed that predictors of AF recurrence were LA EF₂, LA EF₃ and accompanied obstructive sleep apnea (OSA) (P < 0.001, respectively). Decreased functional LA reservoir (LA EF after RVP) and OSA are significantly related to recurrence of AF following CA in patients with paroxysmal AF.