Right ventricular pressure-volume loops using simultaneous radionuclide angiography with a multiwire gamma camera and right heart catheterization

BACKGROUND: The purpose of this study was to generate right ventricular (RV) pressure-volume loops (PVLs) from time-activity curves obtained by first-pass radionuclide angiography (RNA) and RV pressures obtained by right heart catheterization. METHODS AND RESULTS: Short-lived tantalum 178 was used to obtain first-pass RNA at baseline (n = 31), after nitroglycerin (n = 5), or after the conclusion of cardiac catheterization (n = 13). From the radionuclide-derived RV ejection fraction and thermodilution stroke volume, the RV end-diastolic volume and end-systolic volume were measured. Special proprietary software was developed and used to integrate the pressure and the RNA data. The mean heart rate was 80 +/- 17 beats/min; RV ejection fraction, 39% +/- 12%; RV end-diastolic volume, 217 +/- 79 mL; RV end-systolic volume, 142 +/- 74 mL; and RV end-diastolic pressure, 10 +/- 7 mm Hg. The RV PVLs were of high quality and reproducible. CONCLUSIONS: This study provides proof of concept of the feasibility of generating RV PVL; the short half-life (10 minutes) and low energy (59 keV) of Ta-178 allow the generation of multiple loops at low radiation exposure. Such studies could be performed at the bedside and provide a wealth of information that may have clinical and research merits.     

Posttraumatic cardiac dysfunction: assessment with radionuclide ventriculography

The authors studied 54 patients with multisystem trauma, including blunt chest injury, using combined dynamic first-pass and electrocardiographically (ECG) gated radionuclide ventriculography (RNV) to evaluate for posttraumatic myocardial dysfunction. Twenty-six of 54 (48%) patients had abnormalities of ventricular wall motion. The ventricular dysfunction was confined to the right ventricle in 92% of cases. In general, abnormalities consisted of right ventricular dilatation and diffuse hypokinesia, although in seven cases there were localized wall-motion abnormalities. The right ventricular ejection fraction of those patients with wall-motion abnormalities was significantly lower than those with normal studies. Left ventricular ejection fraction did not differ significantly between these groups. ECG changes were not associated with the cardiac dysfunction demonstrated scintigraphically, nor was there a relationship between the number or type of extrathoracic or thoracic injuries demonstrated by RNV. Follow-up studies obtained in 15 cases showed a significant overall improvement in cardiac function by 3 weeks after injury. Combined first-pass and ECG-gated RNV is useful for the identification and follow-up of patients with posttraumatic cardiac dysfunction.     

Accuracy of the automated assessment of left ventricular function with gated perfusion SPECT in the presence of perfusion defects and left ventricular dysfunction: Correlation with equilibrium radionuclide ventriculography and echocardiography

BACKGROUND: Gated single photon emission computed tomography (SPECT) with automated methods allows the quantitative assessment of left ventricular function and perfusion; however, its accuracy must be defined for patients with large earlier infarctions and severe rest perfusion defects, in whom the estimation of endocardial and epicardial borders might be more difficult, even with automated edge-detection techniques. METHODS AND RESULTS: We prospectively compared the automated measurements of left ventricular ejection fraction (LVEF) and volumes from rest-injected gated Technetium 99m (Tc99m) perfusion SPECT with equilibrium radionuclide angiocardiography (ERNA) in 62 patients and the assessment of regional function with echocardiography in 22 patients. Forty-six patients had an earlier myocardial infarction (mean defect size, 34% of left ventricle; SD, 12.7%; range, 8% to 56%); 27 patients had large defects (> or = 20% of left ventricle; LVEF range, 8% to 75%). LVEF, as determined with Cedars-Sinai software (quantitative gated SPECT), correlated well with ERNA (r = 0.941; y = 1.003x + 1.15; P<.0001; SE of the estimate = 6.3%; mean difference -1.3% for LVEF) in the entire study population and in the subgroups of patients with an earlier infarction, severe defects, and large infarctions (> or = 20% of the left ventricle). A correlation existed between gated SPECT and ERNA volumes (r = 0.882, y = 1.040x - 14.7, P<.0001 for end-diastolic volume; r = 0.954, y = 1.147x - 13.9, P<.0001 for end-systolic volumes with the count-ratio technique), but with wider limits of agreement. The exact segmental score agreement between gated SPECT and echocardiography for regional function was 79.8% (281 of 352, kappa = 0.682). CONCLUSIONS: Automated gated SPECT provides an accurate assessment of ejection fraction and regional function, even in the presence of an earlier myocardial infarction with large perfusion defects and significant left ventricular dysfunction.     

Prognostic assessment in coronary artery disease: Role of radionuclide angiography

Left ventricular function is one of the most important determinants, if not the most important determinant, of outcome in paients with coronary artery disease. The ability of radionuclide angiography to assess resting and exercise ejection fraction accurately and reproducibly has been shown to be a critical determinant of survival in large-scale studies of survivors of myocardial infarction, as well as patients with chronic stable angina. In addition, several centers have demonstrated that the exercise ejection fraction is an extremely valuable (and perhaps the most valuable) noninvasive parameter in predicting survival among patients with coronary artery disease. The prognostic insights gained from the exercise ejection fraction add incremental predictive information to the coronary anatomic information obtained from coronary arteriography, especially in patients with multivessel disease and those with left ventricular dysfunction at rest.     

Feasibility of automatic assessment of four-chamber cardiac function with MDCT: Initial clinical application and validation

Background

The ability to perform a simultaneous analysis of ventricular and atrial volumes may provide clinically useful information for diagnosis and prognosis. We aimed to evaluate the feasibility and clinical value of a novel algorithm that performs fully automatic evaluation of the four cardiac chambers and myocardium from gated CT datasets.

Methods

50 patients were studied—Group 1: 30 consecutive unselected patients, Group 2A: 10 patients after myocardial infarction and Group 2B: 10 normal controls. Fully automatic, segmentation of the heart was performed with a model-based segmentation algorithm requiring no user input other than loading the datasets. Qualitative and quantitative evaluation of segmentation quality was performed. Left ventricular (LV) and right ventricular (RV) stroke volumes (SV) were compared.

Results

Overall, segmentation succeeded in all patients although 11/500 (2.2%) cardiac chambers achieved poor segmentation grading. Correlation coefficients between automatic and manually derived volumes were excellent (r > 0.98) for all chambers. Bland-Altman analysis showed minimal bias (−1.0 ml, 0.4 ml, −1.8 ml) for the LV and RV, and right atria, respectively, with mild overestimation of LV myocardial volume (5.2 ml). Significant, yet consistent, overestimation of left atrial volume (23.6 ml) due to inclusion of proximal pulmonary veins was observed. LV and RV ejection fraction (r = 0.91 and 0.98) and SV (r = 0.98 and 0.99) also correlated closely with minimal bias (<2%). Most significantly, LV SV (91.0 ± 21.6 ml) correlated highly with RV SV (81.7 ± 18.2 ml, r = 0.86). Outliers could usually be explained by valvular regurgitation.

Conclusions

Fully automatic segmentation of all cardiac chambers can be achieved with high accuracy over multiple cardiac phases, enabling reliable comprehensive evaluation of four-chamber cardiac function.     

Radionuclide monitoring of left ventricular function after sublingual nifedipine administration at rest and during moderate physical activity

BACKGROUND: This study investigates the acute effects of nifedipine administration on left ventricular (LV) function in patients with different degrees of heart failure at a fixed heart rate under resting conditions and during moderate physical activity. METHODS AND RESULTS: Eleven patients with non-rate-responsive DDD pacemakers were studied. According to baseline LV ejection fraction, patients were divided into 2 groups: 6 patients with an ejection fraction of less than 50% (group 1) and 5 patients with an ejection fraction of 50% or more (group 2). LV function was monitored by a radionuclide system (Vest) at rest and during moderate physical activity (10-minute walk test) before and after sublingual nifedipine administration (10 mg). In all patients, both the systolic blood pressure and diastolic blood pressure were significantly reduced (P <.05) 6 minutes after nifedipine administration. In group 1, end-diastolic volume and ejection fraction decreased after 3 minutes and remained significantly lower (P <.05) than resting values until 10 minutes after drug administration, whereas end-systolic volume was unchanged. In group 2, nifedipine induced a minor decrease in end-diastolic volume and a slight but not significant decrease in ejection fraction and end-systolic volume. During the walk test, nifedipine induced similar changes in all parameters of cardiac performance in both groups. CONCLUSIONS: In patients with impaired LV function, acute nifedipine administration has a negative effect on cardiac performance, which occurs before blood pressure reduction. On the other hand, during moderate physical activity, nifedipine does not affect the improvement in LV function.     

超声心动图评估心肌梗死后心力衰竭患者左心功能的变化

目的 探讨心肌梗死(MI)后心力衰竭(HF)患者采用超声心动图进行左心功能变化评估的临床价值.方法 选取2014年1月-2020年6月收治的MI后HF患者60例作为研究对象,根据美国心脏协会的心功能分级(NYHA)分为A组(心功能Ⅱ级,20例),B组(心功能Ⅲ级,20例),C组(心功能Ⅳ级,20例),选取同期50例健康...     

卡维地洛与美托洛尔对充血性心力衰竭的疗效和二者的成本─效果分析

目的:观察卡维地洛与美托洛尔治疗充血性心力衰竭(CHF)的远期疗效及二者的成本─效果分析.方法:选择CHF患者114例,随机分3组.A组为对照组,予以血管扩张剂、利尿剂、地高辛、血管紧张素转换酶抑制荆等常规治疗;B组为卡维地洛组,在上述常规治疗的基础上给予卡维地洛.C组在常规治疗基础上给予美托洛尔,随访6个月.用药前后分别观察左室射血分数(LVEF)、左室舒张末期内径(LVEDD)、左室收缩末期内径(LVESD)、心衰症状等指标变化情况.结果:6个月后B组和C组LVEDD、LVESD缩小,LVEF明显提高,心衰症状明显好转.但卡维地洛组LVEF改善优于美托洛尔组:卡维地洛组的成本─效果分析低于美托洛尔组.结论:美托洛尔、卡维地洛均可逆转心室重塑,改善心脏功能.卡维地洛疗效略优于美托洛尔.     

Evaluation of left ventricle diastolic dysfunction in ischemic heart disease by CMR: Correlation with echocardiography and myocardial scarring

Objective

To detect the value of cardiac MR imaging in assessment of left ventricle diastolic function in patients with ischemic heart disease compared to echocardiography and to correlate the degree of dysfunction to the extent of myocardial scarring.

Patients and methods

We examined 40 patients with known coronary artery disease. Mean patient’s age was 48 ± 10. All patients were subjected to 2D echocardiography and CMR including transmitral flow and left atrial planimetry. The degree of diastolic dysfunction was detected and correlated with the echocardiographic results and the extent of myocardial scarring.

Results

On CMR, 35% of the cases had grade I diastolic dysfunction, 35% showed grade II, 15% had grade III while 15% showed normal diastolic function. CMR showed 94.12% sensitivity, 100% specificity and 95% accuracy. Excellent agreement with echocardiography was detected (Kappa coefficient 0.931). There was a significant correlation between the degree of diastolic dysfunction and the extent of myocardial scarring with Spearman’s correlation coefficient of 0.492 and p = 0.028.

Conclusion

CMR has comparative results to echocardiography in assessment of diastolic dysfunction. We found a significant correlation between the degree of diastolic dysfunction and the extent of myocardial scarring.     

替米沙坦对高血压患者左心室重构及血浆B型钠尿肽的影响

目的探讨替米沙坦对左心室重构和血浆BNP浓度的影响。方法选取高血压患者94例,其中不伴左室肥厚（LVH）患者44例,伴LVH患者50例,健康对照组46例。高血压患者给予替米沙坦80mgqd治疗32周。所有对象治疗前后均测左心室重量指数（LVMI）,BNP,射血分数（EF）,用SPSS13.0进行统计分析。结果高血压无LVH组及有LVH组治疗前后各指标有明显差异（P〈0.05）,对照组无明显差异（P〉0.05）;BNP的变化值与LVMI和EF的变化值正相关。结论无高血压者、高血压不伴和伴左室重构者BNP,EF具有明显差异,血浆BNP水平可反映左室重构和左心功能。替米沙坦对抑制和逆转左室重构,改善心功具有显著作用。     

Accuracy and repeatability of left ventricular systolic and diastolic function measurements using an ambulatory radionuclide monitor

The accuracy and repeatability of a new ambulatory radionuclide detector (VEST) for left ventricular systolic (ejection fraction) and diastolic (peak filling rate) measurements were assessed. Seventeen patients underwent equilibrium radionuclide angiography immediately before and immediately after a VEST study. The accuracy was evaluated at the beginning and at the end of the VEST studies. Limits of agreement for the ejection fraction were –1%: 2% at the beginning of the VEST study and –4% at the end. Limits of agreement for the peak filling rate were –0.6: 0.6 at the beginning of the VEST study and –0.7: 0.5 at the end. For both measurements the limits of agreement were well within the clinical range. Repeatability was evaluated in a second group of 11 patients who underwent VEST studies in 2 separate days. The coefficient of repeatability (twice the standard deviation of the differences between the 2 studies) was 13 for the ejection fraction and 0.4 for the peak filling rate. Thus, the VEST is an accurate and repeatable method to measure both the ejection fraction and peak filling rate. Offprint requests to: L. Pace, Sanseverino 5/A, 1-80128 Napoli, Italy     

冠心病慢性心力衰竭患者尿中性粒细胞明胶酶相关脂质运载蛋白的水平及其临床意义

 目的 探讨冠心病慢性心力衰竭患者尿中性粒细胞明胶酶相关脂质运载蛋白(neutrophil gelatinase-associated lipocalin,NGAL)水平变化及临床意义。方法 收集2014-09至2015-04在武警后勤学院附属医院心脏中心就诊的冠心病慢性心力衰竭患者90例,依据NYHA(纽约心脏协会)心功能分级分为Ⅰ级组、Ⅱ级组、Ⅲ～Ⅳ级组,每组30例,健康对照组(30例)。检测各组尿NGAL及血清肌酐(serum creatinine,Scr)、血清N末端B型脑钠肽前体(N-terminal pro-B-type natriuretic peptide,NT-proBNP)水平,测量患者左心室舒张末期内径(left ventricular end-diastolic dimension,LVEDD)、 左室射血分数(left ventricular ejection fraction,LVEF),并分析各组不同指标的水平变化及临床意义。结果 健康对照组,NYHAⅠ级、Ⅱ级、Ⅲ～Ⅳ级组尿NGAL水平随着心力衰竭程度加重(NYHA分级、LVEDD增加、LVEF值下降、NT-proBNP升高)而升高,以NYHAⅢ-Ⅳ级组升高最为明显(P＜0.01);与健康对照组比较NYHAⅡ级组尿NGAL水平即有所升高,具有统计学意义(P＜0.05),而Scr水平较健康对照组变化,差异无统计学意义。结论 冠心病慢性心力衰竭患者尿NGAL水平升高出现于Scr之前,提示尿NGAL是诊断冠心病心力衰竭患者早期肾损害敏感而准确的指标之一。     

Parametric visualization methods for the quantitative assessment of myocardial motion

RATIONALE AND OBJECTIVES: The authors performed this study to evaluate three-dimensional (3D) and four-dimensional (4D) techniques for quantifying and visualizing myocardial motion. MATERIALS AND METHODS: The 4D method was performed by using 3D reconstructions of the complete, in vivo, canine heart before and after acute myocardial infarction. Images were obtained with the Dynamic Spatial Reconstructor (1-3) at 15 time points throughout one cardiac cycle. The authors used 0.75-mm-thick sections to allow creation of deformable models at each time point. For the 3D method, electron-beam computed tomographic reconstructions were obtained in anesthetized pigs from eight adjacent short-axis sections of the left ventricle. Data were acquired before and after selective microembolization of the left anterior descending coronary artery at 11 time points throughout one complete cardiaccycle. The authors used 8-mm-thick sections, which did not enable the use of the volumetric 4D approach with deformable models. For the 3D method, images were processed by radially dividing the tomographic images into small circumferential sectors. Color encoding was used for the derived local magnitudes of wall dynamics. RESULTS: The 4D method provided endocardial peak velocities, excursions, and strains throughout systole and diastole. The 3D method provided regional thickness or regional rates of left ventricular wall thickening throughout the cardiac cycle. CONCLUSION: Functional parametric maps of disturbances in regional contractility and relaxation facilitate appreciation of the effect of altered structure-to-function relationships in the myocardium.     

81mKr equilibrium radionuclide ventriculography for the assessment of right heart function

Right heart^81mKr equilibrium radionuclide ventriculography was used to derive right ventricular ejection fraction (RVEF) in 12 healthy male volunteers. Anatomical lung subtraction using^99mTc-MAA perfusion scintigraphy was compared with conventional background correction and the effect of imaging projection on the techniques of image analysis evaluated. Both intra and inter observer variability were reduced by anatomical lung subtraction when compared to conventional background correction. In the right anterior oblique (RAO) projection, background corrected RVEF was lower than lung subtracted RVEF - 0.544 ±0.05 and 0.612±0.08 (mean ± SD) (P<0.02). Lung subtracted RVEF in the anterior projection was lower than that with background correction (P<0.05) and lower than lung subtracted RVEF in the RAO projection (P < 0.001). We conclude that optimal separation of right heart structures is achieved in the RAO projection and that reproducibility of the analytical technique is improved by anatomical lung subtraction.     

Evaluation of right ventricular volume and mass using retrospective ECG-gated cardiac multidetector computed tomography: comparison with first-pass radionuclide angiography

The purposes of this study were to evaluate the right ventricular (RV) volume and mass using cardiac multidetector computed tomography (MDCT) and to compare the cardiac MDCT results with those from first-pass radionuclide angiography (FPRA). Twenty patients were evaluated for the RV end-diastolic volume (RVEDV), the RV end-systolic volume (RVESV), the RV ejection fraction (RVEF), and RV mass using cardiac MDCT with a two-phase reconstruction method based on ECG. The end-diastolic phase was reconstructed at the starting point of the QRS complex on ECG, and the end-systolic phase was reconstructed at the halfway point of the ascending T-wave on ECG. The RV mass was measured for the end-systole. The RVEF was also obtained by FPRA. The mean RVEF (47±7%) measured by cardiac MDCT was well correlated with that (44±6%) measured by FPRA (r=0.854). A significant difference in the mean RVEF was found between cardiac MDCT and FPRA (p=0.001), with an overestimation of 2.9±5.3% by cardiac MDCT versus FPRA. The interobserver variability was 4.4% for the RVEDV, 6.8% for the RVESV, and 7.9% for the RV mass, respectively. Cardiac MDCT is relatively simple and allows the RV volume and mass to be assessed, and the RVEF obtained by cardiac MDCT correlates well with that measured by FPRA.     

Measurement of left ventricular dimensions and function in patients with dilated cardiomyopathy

Studies on medical therapy in heart failure are focused on changes of left ventricular (LV) dimensions and function. These changes may be small, requiring a large study group. We measured LV parameters (LV volumes, LV ejection fraction (LV-EF), and left ventricular mass (LVM)) with two-dimensional echocardiography (2D-echo) and magnetic resonance imaging (MRI) in 50 patients. Based on the difference between the measurements, we determined the variance of the results and calculated the sample sizes needed to detect changes of baseline values. For the calculated and measured parameters we found significant differences between the two techniques: LV-EF and LVM were higher in 2D-echo, and LV dimensions were comparable. The sample size to detect relevant changes from baseline with MRI was significantly (P < 0.01) smaller than in 2D-echo. We conclude that MRI is superior in clinical studies on left ventricular dimensional and functional changes, since measurements are more reproducible and the required sample size is substantially smaller, thereby reducing costs.     

Cardiovascular MRI for the assessment of heart failure: focus on clinical management and prognosis

Cardiovascular MR (CMR) has an emerging role in the noninvasive diagnostic assessment of heart failure (HF). Different imaging sequences allow for a detailed assessment of cardiac morphology, function, myocardial perfusion, tissue characterization, and blood flow measurement. This article reviews the key applications of CMR in HF, with special focus on how CMR may influence the diagnostic and therapeutic approach of HF patients.     

评价室壁瘤患者左室整体和局部收缩与舒张功能受损情况

目的:利用放射性核素心室造影技术评价前壁心肌梗死后室壁瘤形成对左心室整体和局部的收缩及舒张功能的影响。材料和方法:患者分为对照组(G0)15名,单纯前壁心肌梗死组(G1)29名,前壁心肌梗死并发室壁瘤组(G2)15名。运用放射性核素心室造影检查技术测定心功能指标:①左室整体收缩功能参数:LVEF、TPE、PER、1/3EF、1/3ER。②左室整体舒张功能参数:TPF、PFR、1/3FF、1/3FR。③左室局部收缩功能参数:LVREF (6个节段)。④左室局部舒张功能参数:LVR1/3FF(6个节段)。结果:①左室整体收缩功能参数,在LVEF、PER、1/3EF、1/3ER中,G2较G1和G0有明显下降(P<0.001)。②左室整体舒张功能参数,PFR、1/3FF、1/3FR,G2比G1和G0有明显下降(P<0.001)。③左室局部收缩功能参数,LVREF在所有1-6节段G2较G1和G0有明显下降(P<0.01)。④左室舒张功能参数,LVR1/3FF在所有1-6节段G2较G1和G0有明显下降(P<0.01)。结论:左心室壁瘤的形成对左心室整体和局部的收缩和舒张功能已经构成了严重的损害。     

“Balloon valvulotomy” of congenital pulmonary valve stenosis with tricuspid valve insufficiency

The rare congenital anomaly of pulmonary valve stenosis and massive tricuspid valve insufficiency with intact ventricular septum is a lethal condition without reported survival after attempted treatment. In a neonate suffering from this syndrome, the pulmonary valve stenosis was relieved by rupturing the fused valve with a balloon catheter introduced transvenously. The desperate conditon of the patient quickly improved after this procedure, with subsequent disappearance of the tricuspid valve incompetence. Balloon rupturing of fused valves at angiography may represent a therapeutic alternative in cases in which surgical valvulotomy is associated with a high mortality.