Relative merits of left ventricular dyssynchrony, left ventricular lead position, and myocardial scar to predict long-term survival of ischemic heart failure patients undergoing cardiac resynchronization therapy.

BACKGROUND: The relative merits of left ventricular (LV) dyssynchrony, LV lead position, and myocardial scar to predict long-term outcome after cardiac resynchronization therapy remain unknown and were evaluated in the present study. METHODS AND RESULTS: In 397 ischemic heart failure patients, 2-dimensional speckle tracking imaging was performed, with comprehensive assessment of LV radial dyssynchrony, identification of the segment with latest mechanical activation, and detection of myocardial scar in the segment where the LV lead was positioned. For LV dyssynchrony, a cutoff value of 130 milliseconds was used. Segments with <16.5% radial strain in the region of the LV pacing lead were considered to have extensive myocardial scar (>50% transmurality, validated in a subgroup with contrast-enhanced magnetic resonance imaging). The LV lead position was derived from chest x-ray. Long-term follow-up included all-cause mortality and hospitalizations for heart failure. Mean baseline LV radial dyssynchrony was 133±98 milliseconds. In 271 patients (68%), the LV lead was placed at the latest activated segment (concordant LV lead position), and the mean value of peak radial strain at the targeted segment was 18.9±12.6%. Larger LV radial dyssynchrony at baseline was an independent predictor of superior long-term survival (hazard ratio, 0.995; P=0.001), whereas a discordant LV lead position (hazard ratio, 2.086; P=0.001) and myocardial scar in the segment targeted by the LV lead (hazard ratio, 2.913; P<0.001) were independent predictors of worse outcome. Addition of these 3 parameters yielded incremental prognostic value over the combination of clinical parameters. CONCLUSIONS: Baseline LV radial dyssynchrony, discordant LV lead position, and myocardial scar in the region of the LV pacing lead were independent determinants of long-term prognosis in ischemic heart failure patients treated with cardiac resynchronization therapy. Larger baseline LV dyssynchrony predicted superior long-term survival, whereas discordant LV lead position and myocardial scar predicted worse outcome.

Time course of global left ventricular strain after acute myocardial infarction.

AIMS: The purpose of the present study was to assess the evolution of left ventricular (LV) function after acute myocardial infarction (AMI) using global longitudinal peak systolic strain (GLPSS) during 1 year follow-up. In addition, patients were divided in groups with early, late, or no improvement of LV function and predictors of recovery of LV function were established. METHODS AND RESULTS: A total of 341 patients with AMI were evaluated. Two-dimensional echocardiography was performed at baseline, 3, 6, and 12 months. At baseline, LV function was assessed with traditional parameters and GLPSS. Global longitudinal peak systolic strain was re-assessed at 3, 6, and 12 months. Improvement of LV function was based on GLPSS and was observed in 72% of the patients. No differences were observed between patients with early and late improvement. The left anterior descending coronary artery as culprit vessel, peak cardiac troponin T level, diastolic function, and baseline GLPSS were identified as independent predictors of recovery of LV function. CONCLUSION: Improvement of LV systolic function occurred in the majority of patients during follow-up. Global longitudinal peak systolic strain, left anterior descending coronary artery as culprit vessel, peak cardiac troponin T level, and diastolic function were independent predictors of recovery of LV function. Quantification of GLPSS may be of important value for the prediction of recovery of LV function in patients after AMI.

Why, how and when do we need to optimize the setting of cardiac resynchronization therapy?

Current cardiac resynchronization therapy (CRT) devices allow manipulation of the atrioventricular (AV) and interventricular (VV) timings in order to maximize the left ventricular (LV) performance. Multiple echocardiographic and non-echocardiographic methods have been proposed to optimize AV and VV intervals but no consensus has been reached on which methodology should preferably be used. Furthermore, different physiologic conditions, such as rest and exercise, may markedly change LV loading conditions, and therefore an optimal setting determined at rest may be different during exercise. The present article reviews current methodologies to optimize AV and VV interval and discuss why, when and how optimization of these delays may be performed based on current evidence. Moreover, an overview of the results of the multicenter trials on AV and VV intervals optimization is provided.

Automated assessment of the aortic root dimensions with multidetector row computed tomography.

BACKGROUND: Accurate aortic root measurements and evaluation of spatial relationships with coronary ostia are crucial in preoperative transcatheter aortic valve implantation assessments. Standardization of measurements may increase intraobserver and interobserver reproducibility to promote procedural success rate and reduce the frequency of procedurally related complications. This study evaluated the accuracy and reproducibility of a novel automated multidetector row computed tomography (MDCT) imaging postprocessing software, 3mensio Valves (version 4.1.sp1, Medical Imaging BV, Bilthoven, The Netherlands), in the assessment of patients with severe aortic stenosis candidates for transcatheter aortic valve implantation. METHODS: Ninety patients with aortic valve disease were evaluated with 64-row and 320-row MDCT. Aortic valve annular size, aortic root dimensions, and height of the coronary ostia relative to the aortic valve annular plane were measured with the 3mensio Valves software. The measurements were compared with those obtained manually by the Vitrea2 software (Vital Images, Minneapolis, MN). RESULTS: Assessment of aortic valve annulus and aortic root dimensions were feasible in all the patients using the automated 3mensio Valves software. There were excellent agreements with minimal bias between automated and manual MDCT measurements as demonstrated by Bland-Altman analysis and intraclass correlation coefficients ranging from 0.97 to 0.99. The automated 3mensio Valves software had better interobserver reproducibility and required less image postprocessing time than manual assessment. CONCLUSIONS: Novel automated MDCT postprocessing imaging software (3mensio Valves) permits reliable, reproducible, and automated assessments of the aortic root dimensions and spatial relations with the surrounding structures. This has important clinical implications for preoperative assessments of patients undergoing transcatheter aortic valve implantation.

Imaging to guide transcatheter aortic valve implantation.

This review article summarizes the value of multi-modality imaging, including 3-dimensional transesophageal echocardiography, for patient selection, procedural guidance, and follow-up of transcatheter aortic valve implantation.

Transcatheter aortic valve implantation: role of multimodality cardiac imaging.

Current evidence based on more than 8000 high-risk patients with severe aortic stenosis has demonstrated that transcatheter aortic valve implantation (TAVI) is a feasible alternative to surgical aortic valve replacement in selected patients. Despite current promising results on hemodynamic and clinical improvements, there are several unresolved safety issues, such as the frequency of vascular complications, postprocedural paravalvular leak, atrioventricular heart block and stroke. Multimodality cardiac imaging may help to minimize these complications and may play a central role before (optimizing patient selection, selection of appropriate prosthesis size and anticipating the procedural approach), during and after TAVI (evaluating the immediate and long-term procedural results). This article reviews the state-of-the-art TAVI procedures and the role that multimodality cardiac imaging plays before, during and after TAVI.

Effect of biventricular pacing on diastolic dyssynchrony.

OBJECTIVES: This study sought to examine the changes in diastolic dyssynchrony with cardiac resynchronization therapy (CRT). BACKGROUND: Little is known about the effect of CRT on diastolic dyssynchrony. METHODS: Consecutive heart failure patients (n = 266, age 65.7 ± 10.0 years) underwent color-coded tissue Doppler imaging at baseline, 48 h, and 6 months after CRT. Systolic and diastolic dyssynchrony were defined as maximal time delay in peak systolic and early diastolic velocities, respectively, in 4 basal LV segments. CRT responders were defined as those with ≥15% decrease in LV end-systolic volume at 6 months. RESULTS: Baseline LVEF was 25.2 ± 8.1%; 63.5% patients were CRT responders. Baseline incidence of systolic and diastolic dyssynchrony, and a combination of both was 46.2%, 51.9%, and 28.6%, respectively. Compared to nonresponders, responders had longer baseline systolic (79.2 ± 43.4 ms vs. 45.4 ± 30.4 ms; p < 0.001) and diastolic (78.5 ± 52.0 ms vs. 50.1 ± 38.2 ms; p < 0.001) delays. In follow-up, systolic delays (45.4 ± 31.6 ms at 48 h; 38.9 ± 26.2 ms at 6 months; p < 0.001) and diastolic delays (49.4 ± 36.3 ms at 48 h; 37.7 ± 26.0 ms at 6 months; p < 0.001) improved only in responders. CONCLUSIONS: At baseline: 1) diastolic dyssynchrony was more common than systolic dyssynchrony in HF patients; 2) nonresponders had less baseline diastolic dyssynchrony compared to responders. After CRT: 1) diastolic dyssynchrony improved only in responders. Further insight into the pathophysiology of diastolic dyssynchrony and its changes with CRT may provide incremental information on patient-specific treatments.

Predictive value of total atrial conduction time estimated with tissue Doppler imaging for the development of new-onset atrial fibrillation after acute myocardial infarction.

Patients who develop new-onset atrial fibrillation (AF) after acute myocardial infarction (AMI) show an increased risk for adverse events and mortality during follow-up. Recently, a novel noninvasive echocardiographic method has been validated for the estimation of total atrial activation time using tissue Doppler imaging of the atria (PA-TDI duration). PA-TDI duration has shown to be independently predictive of new-onset AF. However, whether PA-TDI duration provides predictive value for new-onset AF in patients after AMI has not been evaluated. Consecutive patients admitted with AMIs and treated with primary percutaneous coronary intervention underwent echocardiography <48 hours after admission. All patients were followed at the outpatient clinic for > or =1 year. During follow-up, 12-lead electrocardiography and Holter monitoring were performed regularly, and the development of new-onset AF was noted. Baseline echocardiography was performed to assess left ventricular and left atrial (LA) function. LA performance was quantified with LA volumes, function, and PA-TDI duration. A total of 613 patients were evaluated. LA maximal volume (hazard ratio 1.07, 95% confidence interval 1.04 to 1.11), the total LA ejection fraction (hazard ratio 0.96, 95% confidence interval 0.93 to 0.99) and PA-TDI duration (hazard ratio 1.05, 95% confidence interval 1.04 to 1.06) were univariate predictors of new-onset AF. After multivariate analysis, LA maximal volume and PA-TDI duration independently predicted new-onset AF. Furthermore, PA-TDI duration provided incremental prognostic value to traditional clinical and echocardiographic parameters for the prediction of new-onset AF. In conclusion, PA-TDI duration is a simple measurement that provides important value for the prediction of new-onset AF in patients after AMI.

Left ventricular rotational mechanics in patients with coronary artery disease: differences in subendocardial and subepicardial layers.

OBJECTIVE: Subendocardial and subepicardial layers have opposite orientation of the myofibres and they are differently affected by coronary artery disease. This study investigated the differences in subendocardial and subepicardial left ventricular (LV) twist in patients with coronary artery disease. METHODS: 214 patients were included in the study: 60 with first ST elevation myocardial infarction (STEMI), 111 with chronic ischaemic heart failure (HF) and 43 normal subjects. Real-time three-dimensional echocardiography provided LV volumes and function. Two-dimensional speckle tracking echocardiography differentiating the subendocardial and subepicardial layers was used for the assessment of LV twist. Patients with STEMI were divided into two groups (small and large STEMI). RESULTS: Compared with normal subjects, peak subendocardial LV twist was significantly impaired in patients with STEMI (11.2 ± 6.0° vs 15.3 ± 2.7°, p<0.001). In patients with chronic HF, peak subendocardial LV twist was even more impaired (4.6 ± 3.4°, p<0.001 vs normal subjects and patients with STEMI). Conversely, peak subepicardial LV twist was not statistically different between normal subjects and patients with STEMI (8.9 ± 1.9° vs 8.4 ± 4.4°, p=0.98), whereas it was significantly impaired in patients with chronic HF (2.6 ± 2.5°, p<0.001 vs normal subjects and patients with STEMI). Peak subendocardial LV twist was not statistically different between large and small STEMI, whereas peak subepicardial LV twist was significantly lower in large STEMI than in small STEMI (7.1 ± 4.8° vs 9.6 ± 3.6°, p=0.025). CONCLUSIONS: Subendocardial LV twist is reduced in patients with STEMI and chronic ischaemic HF whereas subepicardial LV twist is reduced only in chronic ischaemic HF. When STEMI are divided into large and small infarctions, it becomes evident that subepicardial LV twist is only reduced in large infarctions.

Incremental prognostic value of novel left ventricular diastolic indexes for prediction of clinical outcome in patients with ST-elevation myocardial infarction.

This study examined the prognostic value of novel diastolic indexes in ST-elevation acute myocardial infarction (AMI), derived from strain and strain rate analysis using 2-dimensional speckle tracking imaging. Echocardiograms were obtained within 48 hours of admission in 371 consecutive patients with first ST-elevation AMI (59.7 +/- 11.6 years old). Indexes of diastolic function including mean strain rate during isovolumic relaxation (SR(IVR)), mean early diastolic strain rate (SR(E)) and mean diastolic strain at peak transmitral E wave (E) were obtained from 3 apical views. Mean early diastolic velocity from 4 basal segments by color-coded tissue Doppler imaging was measured. Indexes of diastolic filling including E/SR(IVR), E/SR(E), E/diastolic strain at E, and E/early diastolic velocity were calculated. The primary end point (composite of death, hospitalization for heart failure, repeat MI, and repeat revascularization) occurred in 84 patients (22.6%) during a mean follow-up of 17.3 +/- 12.2 months. Mean SR(IVR) (p <0.001), multivessel disease (p <0.001), Thrombolysis In Myocardial Infarction grade 0 to 1 flow after percutaneous coronary intervention (p = 0.004), and left ventricular ejection fraction (p = 0.008) were independent predictors of the combined end point on Cox regression analysis. Mean SR(IVR) showed incremental prognostic value over baseline clinical and echocardiographic variables (global chi-square increase from 41.0 to 51.6, p <0.001). After dividing patient population based on median SR(IVR), patients with SR(IVR) < or =0.24/second had significantly higher event rates than others (hazard ratio 2.74, 95% confidence interval 1.61 to 4.67, p <0.001). In conclusion, SR(IVR) was incremental to left ventricular ejection fraction, Thrombolysis In Myocardial Infarction grade 0 to 1 flow after percutaneous coronary intervention, and multivessel disease and superior to other diastolic indexes in predicting future cardiovascular events after AMI. SR(IVR) may be useful in identifying high-risk patients soon after AMI.

Comparison of aortic root dimensions and geometries before and after transcatheter aortic valve implantation by 2- and 3-dimensional transesophageal echocardiography and multislice computed tomography.

BACKGROUND: 3D transesophageal echocardiography (TEE) may provide more accurate aortic annular and left ventricular outflow tract (LVOT) dimensions and geometries compared with 2D TEE. We assessed agreements between 2D and 3D TEE measurements with multislice computed tomography (MSCT) and changes in annular/LVOT areas and geometries after transcatheter aortic valve implantations (TAVI). METHODS AND RESULTS: Two-dimensional circular (pixr(2)), 3D circular, and 3D planimetered annular and LVOT areas by TEE were compared with "gold standard" MSCT planimetered areas before TAVI. Mean MSCT planimetered annular area was 4.65+/-0.82 cm(2) before TAVI. Annular areas were underestimated by 2D TEE circular (3.89+/-0.74 cm(2), P<0.001), 3D TEE circular (4.06+/-0.79 cm(2), P<0.001), and 3D TEE planimetered annular areas (4.22+/-0.77 cm(2), P<0.001). Mean MSCT planimetered LVOT area was 4.61+/-1.20 cm(2) before TAVI. LVOT areas were underestimated by 2D TEE circular (3.41+/-0.89 cm(2), P<0.001), 3D TEE circular (3.89+/-0.94 cm(2), P<0.001), and 3D TEE planimetered LVOT areas (4.31+/-1.15 cm(2), P<0.001). Three-dimensional TEE planimetered annular and LVOT areas had the best agreement with respective MSCT planimetered areas. After TAVI, MSCT planimetered (4.65+/-0.82 versus 4.20+/-0.46 cm(2), P<0.001) and 3D TEE planimetered (4.22+/-0.77 versus 3.62+/-0.43 cm(2), P<0.001) annular areas decreased, whereas MSCT planimetered (4.61+/-1.20 versus 4.84+/-1.17 cm(2), P=0.002) and 3D TEE planimetered (4.31+/-1.15 versus 4.55+/-1.21 cm(2), P<0.001) LVOT areas increased. Aortic annulus and LVOT became less elliptical after TAVI. CONCLUSIONS: Before TAVI, 2D and 3D TEE aortic annular/LVOT circular geometric assumption underestimated the respective MSCT planimetered areas. After TAVI, 3D TEE and MSCT planimetered annular areas decreased as it assumes the internal dimensions of the prosthetic valve. However, planimetered LVOT areas increased due to a more circular geometry.

Predictors of death and occurrence of appropriate implantable defibrillator therapies in patients with ischemic cardiomyopathy.

Most patients with chronic ischemia and an implantable cardiac defibrillator (ICD) for primary prevention do not experience therapies for ventricular arrhythmias on follow-up. The present study aimed to identify independent clinical, electrocardiographic, and echocardiographic predictors of death and occurrence of ICD therapy in patients with chronic ischemic cardiomyopathy and ICD for primary prevention. A total of 424 patients with chronic ischemic cardiomyopathy, ejection fraction ≤ 35%, and New York Heart Association (NYHA) class ≥ II were recruited. All patients underwent echocardiography before ICD insertion. Primary outcome was all-cause mortality; secondary outcome was occurrence of appropriate ICD therapy on follow-up. Primary and secondary outcomes occurred in 84 and 95 patients, respectively. Patients who died were more likely to have diabetes (hazard ratio [HR] 1.67, 95% confidence interval [CI] 1.00 to 2.79, p = 0.049), higher NYHA class (HR 1.96, 95% CI 1.15 to 3.33, p = 0.013), lower peri-infarct strain on echocardiogram (HR 1.25, 95% CI 1.07 to 1.46, p = 0.005), and lower glomerular filtration rate (HR 1.01, 95% CI 1.00 to 1.03, p = 0.022). Only peri-infarct strain (HR 1.22, 95% CI 1.09 to 1.36, p < 0.001) predicted the occurrence of ICD therapy on follow-up. In conclusion, in chronic ischemic patients with an ICD for primary prevention, the presence of diabetes, renal dysfunction, higher NYHA class, and impaired peri-infarct zone function were predictors of all-cause mortality. In contrast, only impaired peri-infarct zone function determined the occurrence of appropriate ICD therapy on follow-up.

Mitral valve morphology assessment: three-dimensional transesophageal echocardiography versus computed tomography.

BACKGROUND: Advances in the minimally invasive mitral valve repair techniques increase the demands on accurate and reliable morphologic assessment of the mitral valve using three-dimensional imaging modalities. The present study compared mitral valve geometry measurements obtained by three-dimensional transesophageal echocardiography (TEE) to those obtained with multidetector row computed tomography (MDCT) used as a standard reference. METHODS: Clinical preoperative MDCT and intraoperative three-dimensional TEE were performed in 43 patients (mean age 81.0 ± 7.7 years) considered for transcatheter valve implantation procedure. Various measurements of mitral valve geometry were obtained from three-dimensional TEE datasets using mitral valve quantification software, and compared with those obtained from MDCT images using multiplanar reformation planes. RESULTS: Moderate and severe mitral regurgitation was present in 48.9% of patients. There was good agreement in mitral valve geometry measurements between three-dimensional TEE and MDCT without significant overestimation or underestimation and tight 95% limits of agreement. For linear dimensions, angles and areas, the 95% limits of agreement were less than 1 cm, less than 15 degrees, and less than 2 cm(2), respectively. In addition, the intraclass correlation coefficients were more than 0.8 for all parameters. Finally, the measurements were highly reproducible, with low intraobserver and interobserver variability (nonsignificant overestimation or underestimation and narrow 95% limits of agreement). CONCLUSIONS: The present study demonstrates the accuracy and clinical feasibility of the assessment of the mitral valve geometry with three-dimensional TEE that is comparable to the MDCT measurements. Three-dimensional TEE and MDCT provide accurate and complementary information in the evaluation of patients with mitral valve disease. Its potential incremental clinical value in the field of transcatheter mitral repair procedures needs further assessment in the future studies.

Quantitative assessment of mitral regurgitation: comparison between three-dimensional transesophageal echocardiography and magnetic resonance imaging.

BACKGROUND: quantification of mitral regurgitation severity with 2-dimensional (2D) imaging techniques remains challenging. The present study compared the accuracy of 2D transesophageal echocardiography (TEE) and 3-dimensional (3D) TEE for quantification of mitral regurgitation, using MRI as the reference method. METHODS AND RESULTS: two-dimensional and 3D TEE and cardiac MRI were performed in 30 patients with mitral regurgitation. Mitral effective regurgitant orifice area (EROA) and regurgitant volume (Rvol) were estimated with 2D and 3D TEE. With 3D TEE, EROA was calculated using planimetry of the color Doppler flow from en face views and Rvol was derived by multiplying the EROA by the velocity time integral of the regurgitant jet. Finally, using MRI, mitral Rvol was quantified by subtracting the aortic flow volume from left ventricular stroke volume. Compared with 3D TEE, 2D TEE underestimated the EROA by a mean of 0.13 cm(2). In addition, 2D TEE underestimated the Rvol by 21.6% when compared with 3D TEE and by 21.3% when compared with MRI. In contrast, 3D TEE underestimated the Rvol by only 1.2% when compared with MRI. Finally, one third of the patients in grade 1 and ≥50% of the patients in grade 2 and 3, as assessed with 2D TEE, would have been upgraded to a more severe grade, based on the 3D TEE and MRI measurements. CONCLUSIONS: quantification of mitral EROA and Rvol with 3D TEE is feasible and accurate as compared with MRI and results in less underestimation of the Rvol as compared with 2D TEE.

Prediction of atrial fibrillation in patients with an implantable cardioverter-defibrillator and heart failure.

AIMS: Heart failure and atrial fibrillation (AF) frequently coexist and AF worsens heart failure prognosis. Device-based diagnostics derived from implantable cardioverter-defibrillator (ICD) interrogation provide an accurate method for detecting AF episodes. This study sought to determine clinical and echocardiographic predictors of AF occurrence, including an index of total atrial conduction time derived by tissue Doppler imaging (PA-TDI duration), in patients with heart failure. Moreover, the role of PA-TDI duration on the prediction of AF occurrence in subgroups of patients with and without history of AF was explored. METHODS AND RESULTS: A cohort of 495 heart failure patients who underwent ICD implantation was studied. Baseline echocardiographic parameters of systolic and diastolic function were evaluated together with clinical parameters. Furthermore, PA-TDI duration was measured. All patients were prospectively followed up after ICD implantation for AF occurrence detected by ICD interrogation. A total of 142 (29%) patients experienced AF over a follow-up period of 16.4 ± 11.2 months. PA-TDI duration was longer in patients with AF occurrence when compared with patients without AF occurrence (154 ± 27 vs. 135 ± 24 ms, P < 0.001). On Cox-multivariable analysis, female gender [hazard ratio = 1.60; 95% confidence intervals (CI) = 1.09-2.35; P = 0.017], history of AF (hazard ratio = 2.22; 95% CI, 1.51-3.27; P < 0.001), and PA-TDI duration (hazard ratio = 1.27; 95% CI, 1.13-1.42; P < 0.001) were independent predictors of AF occurrence. In the subgroups of patients with and without history of AF, PA-TDI duration remained an independent predictor of AF occurrence. CONCLUSION: PA-TDI duration may be useful to risk-stratify for AF occurrence in heart failure patients with and without a history of AF.