Mid-term outcomes of delivery catheter-based and stylet-based right ventricular septal pacing: Follow-up results from a multicenter, prospective, randomized study.

Background: The Mt FUJI study was a multicenter, prospective, randomized, single-blind, controlled trial comparing delivery catheter-based and stylet-based right ventricular (RV) lead placement at the RV septum. This study extended the follow-up duration to 1 year after implantation. Methods: Seventy patients with pacemaker indications for atrioventricular block were randomly assigned to the delivery catheter and stylet groups. We compared the mid-term efficacy and safety between the two groups at 1 year after implantation. The primary outcome was the change in the left ventricular ejection fraction (LVEF), and the secondary outcomes were changes in brain natriuretic peptide (BNP) levels, lead parameters, paced QRS duration, and the incidence of adverse events. Results: At the 1-year follow-up, no significant differences were observed in the changes in the LVEF (+1.0% ± 8.6% vs. +3.1% ± 8.1%, p = .332), BNP levels (+8.0 [-11.1, 26.5] pg/mL vs. -8.7 [-15.3, 13.2] pg/mL, p = .193), or lead performance between the delivery catheter and stylet groups. The QRS duration was significantly shorter in the delivery catheter group than in the stylet group (128 ± 23 ms vs. 146 ± 17 ms, p < .001). All-cause death, hospitalization for heart failure, new development of atrial fibrillation, and pacing-induced cardiomyopathy occurred in seven patients in the delivery catheter group and five in the stylet group. Conclusion: The delivery catheter system was similarly useful and safe compared to the stylet system in the mid-term follow-up from the Mt FUJI trial. Further long-term evaluations are warranted.

Delivery catheter system carries more physiological right ventricular septal pacing than stylet system.

INTRODUCTION: The Mt. FUJI multicenter trial demonstrated that a delivery catheter system had a higher rate of successful right ventricular (RV) lead deployment on the RV septum (RVS) than a conventional stylet system. In this subanalysis of the Mt. FUJI trial, we assessed the differences in electrocardiogram (ECG) parameters during RV pacing between a delivery catheter system and a stylet system and their associations with the lead tip positions. METHODS: Among 70 patients enrolled in the Mt FUJI trial, ECG parameters, RV lead tip positions, and lead depth inside the septum assessed by computed tomography were compared between the catheter group (n = 36) and stylet group (n = 34). RESULTS: The paced QRS duration (QRS-d), corrected paced QT (QTc), and JT interval (JTc) were significantly shorter in the catheter group than in the stylet group (QRS-d: 130 ± 19 vs. 142 ± 15 ms, p = .004; QTc: 476 ± 25 vs. 514 ± 20 ms, p < .001; JTc: 347 ± 24 vs. 372 ± 17 ms, p < .001). This superiority of the catheter group was maintained in a subgroup analysis of patients with an RV lead tip position at the septum. The lead depth inside the septum was greater in the catheter group than in the stylet group, and there was a significant negative correlation between the paced QRS-d and the lead depth. CONCLUSION: Using a delivery catheter system carries more physiological depolarization and repolarization during RVS pacing and deeper screw penetration in the septum in comparison to conventional stylet system. The lead depth could have a more impact on the ECG parameters rather than the type of pacing lead.

Usefulness of delivery catheter on accurate right ventricular septal pacing: Mt FUJI trial.

AIMS: Although the delivery catheter system for pacemaker-lead implantation is a new alternative to the stylet system, no randomized controlled trial has addressed the difference in right ventricular (RV) lead placement accuracy to the septum between the stylet and the delivery catheter systems. This multicentre prospective randomized controlled trial aimed to prove the efficacy of the delivery catheter system for accurate delivery of RV lead to the septum. METHODS AND RESULTS: In this trial, 70 patients (mean age 78 ± 11 years; 30 men) with pacemaker indications of atrioventricular block were randomized to the delivery catheter or the stylet groups. Right ventricular lead tip positions were assessed using cardiac computed tomography within 4 weeks of pacemaker implantation. Lead tip positions were classified into RV septum, anterior/posterior edge of the RV septal wall, and RV free wall. The primary endpoint was the success rate of RV lead tip placement to the RV septum. RESULTS: Right ventricular leads were implanted as per allocation in all patients. The delivery catheter group had higher success rate of RV lead deployment to the septum (78 vs. 50%; P = 0.024) and narrower paced QRS width (130 ± 19 vs. 142 ± 15 ms P = 0.004) than those in the stylet group. However, there was no significant difference in procedure time [91 (IQR 68-119) vs. 85 (59-118) min; P = 0.488] or the incidence of RV lead dislodgment (0 vs. 3%; P = 0.486). CONCLUSION: The delivery catheter system can achieve a higher success rate of RV lead placement to the RV septum and narrower paced QRS width than the stylet system. TRIAL REGISTRATION NUMBER: jRCTs042200014 (https://jrct.niph.go.jp/en-latest-detail/jRCTs042200014).

Global and Regional Right Ventricular Function Assessed by Novel Three-Dimensional Speckle-Tracking Echocardiography.

BACKGROUND: Accurate assessment of global and regional right ventricular (RV) systolic function is challenging. The aims of this study were to confirm the reliability and feasibility of a three-dimensional (3D) speckle-tracking echocardiography (STE) system, using comparison with cardiac magnetic resonance imaging (CMR), and to assess the contribution of regional RV function to global function. METHODS: In a retrospective, cross-sectional study setting, RV volumetric data were studied in 106 patients who were referred for both CMR and 3D echocardiography within 1 month. Three-dimensional STE-derived area strain, longitudinal strain, and circumferential strain were assessed as global, inlet, outflow, apical, and septal segments. RESULTS: Seventy-five patients (70%) had adequate 3D echocardiographic data. RV measurements derived from 3D STE and CMR were closely related (RV end-diastolic volume, R2 = 0.84; RV end-systolic volume, R2 = 0.83; RV ejection fraction [RVEF], R2 = 0.70; P < .001 for all). RVEF and RV end-diastolic volume from 3D STE were slightly but significantly smaller than CMR values (mean differences, -2% and -10 mL for RVEF and RV end-diastolic volume, respectively). Among conventional echocardiographic parameters for RV function (tricuspid annular plane systolic excursion, fractional area change, S' of the tricuspid annulus, RV free wall two-dimensional longitudinal strain), only fractional area change was significantly related to RVEF (r = 0.34, P = .003). Among segmental 3D strain variables, inlet area strain (r = -0.56, P < .001) and outflow circumferential strain (r = -0.42, P < .001) were independent factors associated with CMR-derived RVEF. CONCLUSIONS: RV volume and RVEF determined by 3D STE were comparable with CMR measurements. Regional RV wall motion showed that heterogeneous segmental deformations affect global RV function differently; specifically, inlet area strain and outflow circumferential strain were significant factors associated with RVEF in patients with underlying heart diseases.

Right Ventricular Deformation Analyses Using a Three-Dimensional Speckle-Tracking Echocardiographic System Specialized for the Right Ventricle.

BACKGROUND: Given the complex morphologic nature of the right ventricle, three-dimensional (3D) approaches would be more appropriate for assessing right ventricular (RV) function than two-dimensional approaches. Thus, the investigators have developed a novel 3D speckle-tracking echocardiographic (STE) system specialized for the right ventricle. The aim of this study was to assess the characteristics of RV global and regional deformation as well as changes on stress tests using the 3D STE system in experimental studies. METHODS: In 10 sheep, sonomicrometry crystals were implanted to validate 3D STE data in the RV endocardium of seven RV segments, including the basal and mid anterior, lateral and inferior wall, and outflow free wall. Full-volume 3D STE data sets and sonomicrometric data were acquired at baseline, during pulmonary artery banding (PAB)-induced moderate (peak RV pressure > 40 mm Hg) and severe (peak RV pressure > 60 mm Hg) RV pressure increases, and during propranolol infusion. The 3D STE area change ratio (ACR), longitudinal strain (LS), and circumferential strain (CS) were measured, and RV global and all segmental deformation data were compared between baseline and stress tests. To assess clinical feasibility, 30 control subjects and 11 patients with pulmonary arterial hypertension were enrolled. RESULTS: All combined 3D STE data were significantly correlated with the sonomicrometric data (ACR, R(2) = 0.88; LS, R(2) = 0.84; CS, R(2) = 0.82; P < .001). In all seven segments, the 3D STE data correlated with the sonomicrometric data (R(2) = 0.72-0.90, P < .001). Global ACR and LS data showed significant differences among baseline, moderate PAB, and severe PAB; however, CS differed only between baseline and severe PAB. The magnitudes of segmental deformation in the free wall were larger than those in the septum and apex under all conditions (P < .05) except LS during severe PAB. Segmental analyses also showed similar responses during stress tests; the ACR in each segment differed significantly between conditions. In all but the apical segments, LS showed significant reductions from moderate PAB; in contrast, CS was significantly reduced with severe PAB in all segments. In this clinical study, the acquisition rate of adequate images for analysis of the RV outflow tract was lower (75.6%) compared with the rate in other segments (from 85.4% to 100%). However, the pulmonary arterial hypertension group had lower RV global deformation values than the control group (ACR and LS, P < .001; CS, P = .003), the ACR and LS in basal and middle segments differed significantly between groups, and the outflow and apex did not differ. CONCLUSIONS: A novel 3D STE system specialized for the right ventricle is reliable for RV deformation analyses and may provide additional information about RV global and segmental function. The clinical feasibility of this system is acceptable.

Prevalence and Clinical Determinants of Left Atrial Appendage Thrombus in Patients With Atrial Fibrillation Before Pulmonary Vein Isolation.

The CHADS2 score is considered a reliable predictor of stroke/thromboembolism risk in patients with atrial fibrillation (AF). However, thromboembolism can occasionally occur even in patients with AF with low CHADS2 score (CHADS2 score = 0 or 1). To investigate the incidence and predictors of left atrial appendage (LAA) thrombus (LAAT) formation in patients with AF, we studied consecutive 543 Japanese patients with AF who underwent transesophageal echocardiography before pulmonary vein isolation from 2008 to 2012. All patients were treated with anticoagulation therapy with warfarin, and their clinical and echocardiographic characteristics were evaluated. LAATs were observed in 35 (6.4%) of 543 patients, and the prevalence was clearly correlated with the patient's CHADS2 scores. Of 338 patients with low CHADS2 score, LAATs were observed in 7 patients (2.1%). By multivariate analysis, increased left atrial volume (≥50 ml), decreased ejection fraction (<56%), and increased brain natriuretic peptide level (>75 pg/ml) were significantly associated with increased prevalence of LAATs, even in patients with low CHADS2 score. Accordingly, we proposed a new scoring system to predict LAAT (left atrial volume ≥50 ml: score 2; ejection fraction <56%: score 1; brain natriuretic peptide >75 pg/ml: score 1). Patients with a score ≥2 have a greater risk of LAAT, whereas all patients with score ≤1 have no LAATs. Our scoring system is useful for evaluation of the risk of LAAT in patients with AF even with low CHADS2 score.

Prognostic significance of persistent restrictive filling pattern after cardiac resynchronization therapy.

BACKGROUND: Cardiac resynchronization therapy (CRT) may improve left ventricular (LV) diastolic dysfunction as well as systolic dysfunction. Diastolic dysfunction is a key for prognosis in patients with heart failure; therefore, we aimed to clarify the impact of CRT on diastolic function and prognosis. METHODS: In 67 patients who underwent CRT, LV diastolic function was assessed by pulsed Doppler transmitral flow pattern at baseline and 1 week after CRT, and classified into restrictive filling pattern (RFP) and non-RFP groups. Volume responders were defined by reduction of LV end-systolic volume >15% at 6 months after CRT. The clinical endpoint comprised death from any cause or unplanned hospitalization for a major cardiovascular event (MACE). RESULTS: During the follow-up period (479 ± 252 days), 26 patients (38.8%) had reached the endpoint of MACE. In Cox proportional hazard analyses, RFP at 1 week after CRT was associated with the endpoints independently of age and New York Heart Association (NYHA) class IV at baseline. Thirty (44.8%) patients were identified as volume responders, who had better prognosis than non-responders. Patients were classified into 4 groups based on their filling pattern at 1 week after CRT and volume responses. The worst prognosis was observed in the RFP and non-responder group, and the best was observed in the non-RFP and responder group. For the remaining 2 groups with intermediate prognosis, the RFP and responder group showed poorer prognosis compared to the non-RFP and non-responder group. CONCLUSIONS: Persistent RFP after CRT may be a strong prognostic predictor, which should be treated with more intensive therapy to improve the prognosis of patients following CRT.

Three-dimensional speckle tracking echocardiography.

Speckle tracking echocardiography (STE) was popularized in the first decade of this century. Analysis of cardiac mechanics has been the focus of ultrasonics, and the breakthrough came with STE. Beyond analysis solely of left ventricular ejection fraction, STE allows the assessment of various pathophysiologies, including myocardial layer-specific myocardial function, twist and rotation, and dyssynchrony. Recent developments in the technology have resulted in commercially available 3-dimensional (D)-STE systems. Through experimental studies and clinical investigations, the reliability and feasibility of 3D-STE-derived data have been validated, and the advantages of 3D-STE over 2D-STE have been revealed. In addition, because of the 3D nature of the technology, 3D-STE provides novel deformation parameters (ie, 3D-strain and area change ratio) that have the potential for more accurate assessment of overall and regional myocardial function. Recently, various preliminary studies using 3D-STE have reported on myocardial characteristics, novel mechanics in the left ventricle, prediction of therapeutic effects, observations of cardiac function through interventions, and challenges for left atrial and right ventricular functions. In this review, we focus on the features of the methodology, validation, and clinical application of 3D-ST.

Novel dyssynchrony evaluation by M-mode imaging in left bundle branch block and the application to predict responses for cardiac resynchronization therapy.

BACKGROUND: To determine an appropriate M-mode method in assessing left ventricular (LV) dyssynchrony in left bundle branch block (LBBB), and to assess feasibility of the method to predict cardiac resynchronization therapy (CRT) responses. METHODS AND RESULTS: Fifty-one patients with LBBB were enrolled. Among them 31 patients underwent CRT. In addition to original septal to posterior wall motion delay (SPWMD), first peak-SPWMD was proposed as time of difference between the first septal displacement and the maximum displacement of the posterior. If an early septal point was not present, anatomical M-mode was used to visualize an early septal displacement spreading scan-area until inferoseptal wall. CRT responders were defined as LV end-systolic volume reduction (>15%) at 6 months after CRT. Twenty patients (65%) were identified as CRT responders. First peak-SPWMD in responders was significantly higher than those in nonresponders, although SPWMD did not differ between groups. Strong predicting ability of first peak-SPWMD was revealed (first peak-SPWMD: 80/90/83%; SPWMD: 35/100/58%), and area under the curve in receiver operating characteristic analysis of first peak-SPWMD (0.88) was significantly higher than that of SPWMD (0.61) (p<0.05). CONCLUSION: In patients with LBBB, time differences between early septal and delayed displacement of posterolateral wall on M-mode images were the appropriate dyssynchrony parameter, and could improve the predictive ability for CRT responses.

Diastolic suction in heart failure: impact of left ventricular geometry, untwist, and flow mechanics.

AIMS: Vector flow mapping (VFM) can be used to assess intraventricular hemodynamics quantitatively. This study assessed the magnitude of the suction flow kinetic energy with VFM and investigated the relation between left ventricular (LV) function and geometry in patients with an estimated elevated LV filling pressure. MATERIALS AND METHODS: We studied 24 subjects with an elevated LV filling pressure (EFP group) and 36 normal subjects (normal group). Suction was defined as flow directed toward the apex during the period from soon after systolic ejection to before mitral inflow. The flow kinetic energy index was quantified as the sum of the product of the blood mass and velocity vector and its magnitude to the peak value was measured. KEY FINDINGS: Suction flow was observed in 12 (50%) EFP-group patients and 36 (100%) normal-group subjects. The magnitude of the suction kinetic energy index was significantly smaller in EFP versus normal group (2.7 ± 3.8 vs. 5.7 ± 4.4 g/s/cm(2), P<0.01). The EFP-group patients with suction had a smaller LV end-systolic volume (ESV) (P<0.01), greater ellipsoidal geometry (P<0.05) and untwisting rate (P<0.01) than the EFP-group patients without suction. A regression analysis indicated a significant linear relation between the suction kinetic energy index and LVEF (r=0.43, P=0.04), ESV (r=-0.40, P=0.05), eccentricity index (r=0.44, P=0.04), and untwisting rate (r=0.51, P=0.04). SIGNIFICANCE: The magnitude of the suction flow kinetic energy index derived from VFM may allow the quantitative assessment of the suction flow, which correlates with LV systolic function, geometry, and untwisting mechanics.

Feasibility of left ventricular volume measurements by three-dimensional speckle tracking echocardiography depends on image quality and degree of left ventricular enlargement: validation study with cardiac magnetic resonance imaging.

BACKGROUND: Novel 3-dimensional echocardiography with speckle tracking imaging (3D-STE) may have advantages in assessing left ventricular (LV) volume through a cardiac cycle. The feasibility of 3D-STE may be affected by image quality and LV morphology. METHODS AND RESULTS: We studied 64 patients (38 men, age 55±12 years) who underwent cardiac magnetic resonance imaging (CMRI) and 3D-STE on the same day. LV end-diastolic volume (EDV) and end-systolic volume (ESV) were measured by both modalities. Imaging qualities were quantified in each of 6 LV segments by an imaging quality score (IQS) of 1-3, and scores were averaged (mean IQS) at end-diastole and end-systole. Compared to CMRI, 3D-STE showed a tendency to underestimate LV volume measurements, but not significantly (EDV: bias=-18±37ml; ESV: bias=-10±34ml), and measurements correlated well with those by CMRI (EDV: R=0.80, ESV: R=0.86, ejection fraction: R=0.75, p<0.001). The absolute differences of LVEDV and ESV between 3D-STE and CMRI correlated significantly with mean IQS (LVEDV, R=-0.35, p=0.005; LVESV, R=-0.30, p=0.02). Based on the medium value of LVEDV by CMRI (127ml), subjects were classified into the small (<127ml) and large LVEDV (≧127ml) groups. In the large LVEDV group, mean IQS significantly correlated with the absolute differences of LVEDV (mean IQS, r=-0.45, p=0.01), despite no significant correlation in the small LVEDV group. CONCLUSION: 3D-STE could measure LV volume as well as CMRI, however, its accuracy depends on the quality of the acquired image and particularly on enlargement of the left ventricle.

Efficacy, safety, and outcomes of catheter ablation of atrial fibrillation in patients with heart failure with preserved ejection fraction.

OBJECTIVES: This study sought to investigate the efficacy and safety of catheter ablation for atrial fibrillation (AF) in patients with heart failure with preserved ejection fraction (HFPEF). BACKGROUND: AF is a precipitating factor for clinical deterioration of HFPEF. METHODS: Catheter ablation for AF was performed in a consecutive 74 patients with compensated HFPEF (left ventricular [LV] ejection fraction >50%). AF-free probability after catheter ablation and factors relating to maintenance of sinus rhythm were investigated. LV strain and strain rate were assessed by echocardiography at baseline and over 12 months after ablation. RESULTS: During a 34 ± 16-month follow-up period, single- and multiple-procedure drug-free success rates were 27% (n = 20) and 45% (n = 33), respectively. Multiple procedures and pharmaceutically assisted success rate was 73% (n = 54). No major complications occurred during follow-up. Multivariate Cox regression analyses revealed that AF type (other than long-standing persistent AF) and lack of hypertension were independently associated with maintenance of sinus rhythm (hazard ratio [HR]: 1.81, 95% confidence interval [CI]: 1.03 to 3.17, p = 0.04; HR: 0.49, 95% CI: 0.24 to 0.96, p = 0.04, respectively). LV systolic indices (LV ejection fraction, LV strain/strain rate at systole) and diastolic indices (E/E', ratio of LV strain rate at diastole with early transmitral flow) were improved only in patients maintaining sinus rhythm at follow-up. CONCLUSIONS: Our results suggest that AF can be effectively and safely treated with a composite of repeat procedures and pharmaceuticals in patients with HFPEF. However, the current study was a single-arm analysis; therefore, larger randomized control studies are needed to verify the benefit of AF ablation in this cohort.

Application of 3-dimensional speckle tracking imaging to the assessment of right ventricular regional deformation.

BACKGROUND: The aim of this study was to carry out 3-dimensional speckle tracking imaging (3DSTI) of the right ventricle (RV) and evaluate RV regional wall deformation. METHODS AND RESULTS: 3DSTI of the RV was performed in 35 normal subjects, 8 patients with arrhythmogenic right ventricular cardiomyopathy, and 8 patients with pulmonary arterial hypertension. Peak systolic area change ratio and regional contraction timing relative to global systolic time (time to peak strain/time to end-systole×100) were measured in each segment. Good-quality images were acquired of the inflow segment in 87%, apex in 87%, outflow in 57%, and septum in 94% of the 35 normal subjects. In normal subjects, peak systolic area change ratio of the inflow anterior wall was -41±14%; inflow inferior wall, -35±9%; apical anterior wall, -41±10%; apical inferior wall, -31±11%; outflow, -31±9%; and septum wall, -36±11%. Contraction timing of the apical anterior wall and septum wall were earlier than those of other segments. In patients with RV dysfunction, 3DSTI indicated low peak systolic area change ratio in the damaged area. CONCLUSIONS: RV 3DSTI indicated segmental heterogeneity in magnitude and timing of RV contraction. 3DSTI may be a promising modality for providing precise quantitative information on complex RV wall motion.

Relationship between cold temperature and cardiovascular mortality, with assessment of effect modification by individual characteristics: Ibaraki Prefectural Health Study.

BACKGROUND: Cold temperature has been reported to contribute to cardiovascular mortality, but it is not clear which people are more susceptible to cold temperature. METHODS AND RESULTS: The relationship between ambient temperature and mortality was examined in 3,593 subjects from the Ibaraki Prefectural Health Study who died of cardiovascular disease during a mean follow-up period of 9.7±4.0 years. Daily values of meteorological variables were obtained from the Japan Meteorological Agency. Time-stratified case cross-over analysis was used. The multivariate odds ratios (ORs; 95% confidence interval) per 1°C decrease in daily maximum temperature over the day of death and the 2 days prior to this day adjusted for relative humidity were 1.018 (1.003-1.034) for all cardiovascular deaths and 1.025 (1.003-1.048) for stroke deaths. Risk-stratified analysis showed that younger subjects aged <80 years and those with hyperglycemia were more susceptible to cold temperature. The OR of all cardiovascular deaths related to cold temperature was 1.034 (1.012-1.056) for subjects aged <80 years, and that of stroke deaths was 1.076 (1.023-1.131) for those with hyperglycemia. CONCLUSIONS: Exposure to cold temperature triggers cardiovascular deaths. Additionally, younger age and hyperglycemia could enhance susceptibility to cold temperature.

Significant improvement of left atrial and left atrial appendage function after catheter ablation for persistent atrial fibrillation.

BACKGROUND: The long-term effects of catheter ablation (CA) on the left atrium and left atrial appendage (LAA) are unknown in persistent atrial fibrillation (AF). This study investigated left atrial (LA) reverse remodeling and evolution of LA/LAA function after successful CA for persistent AF and identified predictors for maintenance of sinus rhythm (SR) and LA reverse remodeling. METHODS AND RESULTS: CA was performed in 123 patients with persistent AF. LA volumes, LA strain and LAA wall velocity were assessed both at baseline and at 12 months after ablation. Patients who maintained SR were divided into 2 groups according to whether LA volume decreased by ≥15% at follow-up (responders) or not (non-responders). During a follow-up period of 18±2 months, AF recurred in 45 patients (37%). Of the remaining 78 patients (63%) without recurrent AF, 62 patients (79%) were classified as responders. LA/LAA function significantly improved and the prevalence of spontaneous echo contrast decreased only in responders at follow-up. LA systolic strain and LAA wall velocity were independent predictors of both maintenance of SR (odds ratio [OR], 2.57; P=0.003; OR, 3.02; P=0.002, respectively) and LA reverse remodeling (OR, 4.44; P=0.007; OR, 3.52; P=0.01, respectively). CONCLUSIONS: Successful CA is associated with LA reverse remodeling and LA/LAA functional recovery in patients with persistent AF. LA systolic strain and LAA wall velocity at baseline predicted both maintenance of SR and LA reverse remodeling.

Abnormal early diastolic intraventricular flow 'kinetic energy index' assessed by vector flow mapping in patients with elevated filling pressure.

AIMS: Recently developed vector flow mapping (VFM) enables evaluation of local flow dynamics without angle dependency. This study used VFM to evaluate quantitatively the index of intraventricular haemodynamic kinetic energy in patients with left ventricular (LV) diastolic dysfunction and to compare those with normal subjects. METHODS AND RESULTS: We studied 25 patients with estimated high left atrial (LA) pressure (pseudonormal: PN group) and 36 normal subjects (control group). Left ventricle was divided into basal, mid, and apical segments. Intraventricular haemodynamic energy was evaluated in the dimension of speed, and it was defined as the kinetic energy index. We calculated this index and created time-energy index curves. The time interval from electrocardiogram (ECG) R wave to peak index was measured, and time differences of the peak index between basal and other segments were defined as ΔT-mid and ΔT-apex. In both groups, early diastolic peak kinetic energy index in mid and apical segments was significantly lower than that in the basal segment. Time to peak index did not differ in apex, mid, and basal segments in the control group but was significantly longer in the apex than that in the basal segment in the PN group. ΔT-mid and ΔT-apex were significantly larger in the PN group than the control group. Multiple regression analysis showed sphericity index, E/E' to be significant independent variables determining ΔT apex. CONCLUSION: Retarded apical kinetic energy fluid dynamics were detected using VFM and were closely associated with LV spherical remodelling in patients with high LA pressure.

Transmural compensation of myocardial deformation to preserve left ventricular ejection performance in chronic aortic regurgitation.

BACKGROUND: In patients with chronic aortic regurgitation (AR), systolic wall stress and volume overload affects left ventricular (LV) systolic function and remodeling. The aim of this study was to assess transmural rearrangements of myocardial deformation to preserve LV ejection performances using speckle-tracking echocardiography in patients with chronic AR. METHODS: Ninety patients with AR were enrolled. On LV short-axis images, total, inner, and outer radial strain and circumferential strain at the inner, mid, and outer layers were calculated. On apical four-chamber images, endocardial longitudinal strain was calculated. End-systolic wall stresses were calculated using previous methods. RESULTS: AR severities were classified as moderate in 31 patients, severe and preserved LV ejection fraction (LVEF) (≥50%) in 42 patients, and severe and reduced LVEF (<50%) in 17 patients. Longitudinal strain was decreased even in the moderate AR group, despite normal end-systolic wall stress. Inner radial strain progressively decreased with increasing end-systolic wall stress, whereas outer radial strain in the moderate and severe AR and preserved LVEF groups was higher than in the control group. Consequently, total radial strain was preserved even in the severe AR and preserved LVEF groups with increased end-systolic wall stress. Similarly, despite reduced inner circumferential strain, outer circumferential strain was higher in the severe AR and preserved LVEF group than in the control group. All strain parameters were lower in the severe AR and reduced LVEF group with dramatically increased end-systolic wall stress than in other groups. CONCLUSIONS: Transmural strain analysis revealed that subendocardial dysfunction accompanied by increased wall thickening at the subepicardium may be a compensatory mechanism of wall thickening to preserve LVEF in patients with chronic AR.

Tissue Doppler imaging dyssynchrony parameter derived from the myocardial active wall motion improves prediction of responders for cardiac resynchronization therapy.

BACKGROUND: The aim of this study was to propose modified tissue Doppler imaging (TDI) parameters derived from the first active wall motion and to assess them for the better prediction of cardiac resynchronization therapy (CRT) responders in comparison with to original TDI parameters. METHODS AND RESULTS: In 61 patients with CRT, time from QRS onset to peak velocities by TDI (Ts), which were derived from active wall motion identified by longitudinal strain rate (LSR) value, were assessed. Time from QRS onset to the negative peak of LSR (TLSR) was also assessed. Modified standard deviation of Ts in 12 left ventricular (LV) segments (Ts-SD), that of TLSR (TLSR-SD), differences of Ts between septum and lateral wall (Ts-SL), and that of TLSR (TLSR-SL) were calculated. Original Ts-SD and Ts-SL were calculated by previously described methods. Responders were defined as patients with LV end-systolic volume reduction (>15%) at 6 months after CRT: 35 patients (57%) were identified as CRT responders. Area under the receiver-operating characteristics curve (AUC) of modified Ts-SD (0.87) was significantly higher than that of Ts-SD (0.65), Ts-SL (0.62), and TLSR-SL (0.69). AUC of modified Ts-SL was significantly higher than those of Ts-SD, and Ts-SL. AUC of TLSR-SD (0.82) also was significantly higher than that of Ts-SD. CONCLUSIONS: Modified TDI dyssynchrony parameters derived from the first active wall motion improve the ability to predict responders to CRT.

Three-dimensional echocardiography in the diagnosis of pacemaker lead perforation.

Recently, due to increases in the number of cardiac device implantations, especially implantable cardioverter-defibrillators and cardiac resynchronization therapy, device complications have been experienced more frequently. Myocardial perforation of an implanted lead is one of the most severe complications. We report a case of ventricular lead perforation clearly visualized by 3-dimensional echocardiography, which was not identified by 2-dimensional echocardiography.