Bas M. van Dalen

First experience in humans using adipose tissue-derived regenerative cells in the treatment of patients with ST-segment elevation myocardial infarction.

To the Editor: In preclinical animal models of acute myocardial infarction (AMI), administration of freshly isolated adipose tissue–derived regenerative cells (ADRCs) immediately after the AMI improved left ventricular (LV) function and myocardial perfusion ([1,2][1]). The predominant working

Importance of transducer position in the assessment of apical rotation by speckle tracking echocardiography.

BACKGROUND Speckle tracking echocardiography is increasingly used to quantify left ventricular (LV) twist. However, one of the limitations of the assessment of LV twist by speckle tracking echocardiography is the crucial dependence on correct acquisition of a LV apical short-axis. This study sought to assess the influence of transducer position on LV apical rotation measurements. METHODS The study population consisted of 58 consecutive healthy volunteers (mean age 38 +/- 13 years, 25 men). To obtain parasternal short-axis images at the LV apical level, the following protocol was used. From the standard parasternal position (LV and aorta most inline, with the mitral valve tips in the middle of the sector) an as-circular-as-possible short-axis image of the LV apex, just proximal to the level with end-systolic LV luminal obliteration, was obtained by angulation of the transducer (position 1). From this position, the position of the transducer was changed to one (position 2) and two (position 3) intercostal spaces more caudal with subsequent similar transducer adaptations. RESULTS In 8 volunteers (14%) parasternal image quality was insufficient for speckle tracking echocardiography. In 13 volunteers (22%) the LV apical short-axis could only be obtained from one transducer position. In the remaining volunteers with two (n = 27) or three (n = 10) available transducer positions, a more caudal transducer position was associated with increased measured LV apical rotation. Mean measured LV apical rotation was 5.2 +/- 1.8 degrees at position 1, 7.3 +/- 2.6 degrees at position 2 (P < .001), and 8.7 +/- 2.2 degrees at position 3 (P < .001 vs position 1 and P < .05 vs position 2). CONCLUSION A more caudal transducer position is associated with increased measured LV apical rotation.

Age-related changes in the biomechanics of left ventricular twist measured by speckle tracking echocardiography

The increasing number and proportion of aged individuals in the population warrants knowledge of normal physiological changes of left ventricular (LV) biomechanics with advancing age. LV twist describes the instantaneous circumferential motion of the apex with respect to the base of the heart and has an important role in LV ejection and filling. This study sought to investigate the biomechanics behind age-related changes in LV twist by determining a broad spectrum of LV rotation parameters in different age groups, using speckle tracking echocardiography (STE). The final study population consisted of 61 healthy volunteers (16-35 yr, n=25; 36-55 yr, n=23; 56-75 yr, n=13; 31 men). LV peak systolic rotation during the isovolumic contraction phase (Rot(early)), LV peak systolic rotation during ejection (Rot(max)), instantaneous LV peak systolic twist (Twist(max)), the time to Rot(early), Rot(max), and Twist(max), and rotational deformation delay (defined as the difference of time to basal Rot(max) and apical Rot(max)) were determined by STE using QLAB Advanced Quantification Software (version 6.0; Philips, Best, The Netherlands). With increasing age, apical Rot(max) (P<0.05), time to apical Rot(max) (P<0.01), and Twist(max) (P<0.01) increased, whereas basal Rot(early) (P<0.001), time to basal Rot(early) (P<0.01), and rotational deformation delay (P<0.05) decreased. Rotational deformation delay was significantly correlated to Twist(max) (R(2)=0.20, P<0.05). In conclusion, Twist(max) increased with aging, resulting from both increased apical Rot(max) and decreased rotational deformation delay between the apex and the base of the LV. This may explain the preservation of LV ejection fraction in the elderly.

Changes in mitral regurgitation after transcatheter aortic valve implantation

Objectives: To assess the acute and intermediate changes in mitral regurgitation (MR) severity after transcatheter aortic valve implantation (TAVI) with the CoreValve Revalving SystemTM (CRS). Background: Following surgical aortic valve replacement, improvement in MR is reported in 27–82% of the patients. The changes in MR severity following CRS implantation are unknown. Methods: Transthoracic echocardiography was performed in 79 consecutive patients before and after treatment, and at the first outpatient visit. Left ventricular dimensions and ejection fraction (LVEF), left atrial (LA) size, and aortic gradient were measured. MR was assessed by color flow mapping and was graded as none, mild, moderate, or severe. It was defined as organic or functional. The depth of CRS implantation was measured by angiography. Results: Post‐treatment, the mean gradient decreased from 48 ± 16 mm Hg to 9 ± 5 mm Hg (P < 0.0001). There was no significant change in the left ventricular dimensions, LA size, and LVEF. MR pretreatment was mild, moderate, or severe in 57%, 18%, and 1% of the patients, respectively. It was defined as organic in 27 patients (36%) and functional in 27 patients (36%). The degree of MR remained unchanged in 61% of the patients, improved in 17%, and worsened in 22%. MR improvement was associated with a lower baseline LVEF (P = 0.02). There was no association between the changes in MR severity and the depth of CRS implantation. Conclusions: Most patients who underwent TAVI had some degree of MR. Overall there was no change in the degree of MR post‐treatment. Patients in whom MR improved had a lower LVEF at baseline.

Accuracy and Reproducibility of Quantitation of Left Ventricular Function by Real-Time Three-Dimensional Echocardiography Versus Cardiac Magnetic Resonance

The aim of this study was to investigate the accuracy and reproducibility of the quantification of left ventricular (LV) function by real-time 3-dimensional echocardiography (RT3DE) using current state-of-the-art hardware and software. Compared with cardiac magnetic resonance (CMR), previous generations of hardware and software for RT3DE significantly underestimated LV volumes partly because of inherent factors such as limited spatial and temporal resolution. Also, RT3DE volumes were compared with short-axis CMR data, whereas a combined short-axis and long-axis analysis is known to be superior. Twenty-four subjects (mean age 51 +/- 12 years, 17 men) in sinus rhythm and with good to excellent 2-dimensional image quality underwent RT3DE and CMR within 1 day. The acquisition of RT3DE data was done with current state-of-the-art hardware and software. Two blinded experts performed off-line LV volume analysis. Global LV volumes were determined from semiautomated border detection on the basis of endocardial speckle tracking with biplane projections using QLAB version 6.0. Volumes derived by magnetic resonance imaging were quantified from combined short-axis and long-axis series. The volume-rate on RT3DE was 33 +/- 8 Hz (range 19 to 42). Excellent correlations were found (R2 > or = 0.97) between CMR and RT3DE for global LV end-diastolic volume, LV end-systolic volume, the LV ejection fraction, and LV phase volumes (24 phases/cardiac cycle). Bland-Altman analyses showed mean differences of -7.1 ml, -4.2 ml, 0.2%, and -5.8 ml and 95% limits of agreement of +/-19.7 ml, +/-8.3 ml, +/-6.2%, and +/-15.4 ml for global LV end-diastolic volume, LV end-systolic volume, the LV ejection fraction, and LV phase volumes, respectively. Interobserver variability was 5.2% for global LV end-diastolic volume, 6.4% for LV end-systolic volume, and 7.6% for the LV ejection fraction. In conclusion, in patients with good acoustic windows, RT3DE using state-of-the-art technology provides accurate and reproducible measurements of global LV volumes, LV volume changes over time, and the LV ejection fraction.

Left ventricular solid body rotation in non-compaction cardiomyopathy: A potential new objective and quantitative functional diagnostic criterion?

Left ventricular (LV) twist originates from the interaction between myocardial fibre helices that are formed during the formation of compact myocardium in the final stages of the development of myocardial architecture. Since non‐compaction cardiomyopathy (NCCM) is probably caused by intrauterine arrest of this final stage, it may be anticipated that LV twist characteristics are altered in NCCM patients, beyond that seen in patients with impaired LV function and normal compaction.

Incidence, Pathophysiology, and Treatment of Complications During Dobutamine-Atropine Stress Echocardiography

modality rapidly expanded from diagnosing coronary artery disease (CAD) to risk stratification of patients undergoing vascular surgery; risk stratification of patients with chronic CAD, unstable angina, acute or chronic myocardial infarction (MI), or valvular heart disease; and the assessment of myocardial viability in patients with severe left ventricular (LV) dysfunction. Thus, dobutamine stress has been applied to progressively more complex, older, and higher-risk patients. Additionally, stress protocols became more aggressive, with higher dobutamine doses and the addition of atropine. 3 Although generally regarded as a safe stress modality, serious complications do occur. In this review, we will describe the incidence, pathophysiology, and treatment of complications during dobutamine-atropine stress echocardiography (DASE). Data on incidence of complications were obtained from 26 studies including 400 patients that reported at least the major complications of mortality, acute MI, ventricular fibrillation, and sustained ventricular tachycardia, 4–29 for a total of 55 071 patients (Table 1). In addition, references are given to case reports and studies dealing specifically with a particular complication.

Usefulness of Left Ventricular Systolic Dyssynchrony by Real-Time Three-Dimensional Echocardiography to Predict Long-Term Response to Cardiac Resynchronization Therapy

Real-time 3-dimensional echocardiography (RT3DE) allows simultaneous timing of regional volumetric changes as a net result of longitudinal, radial, circumferential left ventricular (LV) contraction, hence LV systolic dyssynchrony. We sought to examine real-time 3-dimensional echocardiographically derived dyssynchrony for prediction of long-term response to cardiac resynchronization therapy (CRT) in a prospective study. Ninety consecutive patients with heart failure (mean age 60 +/- 12 years, 73% men, New York Heart Association class III in 97%) underwent clinical and echocardiographic assessments at baseline and at 12 months after CRT including real-time 3-dimensional echocardiographically derived LV systolic dyssynchrony index. The systolic dyssynchrony index (SDI) was defined as the SD of time to minimum systolic volume of the 16 LV segments, expressed in percent RR duration. CRT response was defined as a >15% decrease in LV end-systolic volume on real-time 3-dimensional echocardiogram. After 12 months of CRT, 68 patients (76%) were responders. Feasibility of the SDI was 94%. An SDI >10% predicted CRT response with good sensitivity (96%), specificity (88%), positive likelihood ratio (8), and negative likelihood ratio (0.05). Patients with an SDI >10% had mean change (-21%, -31%, 39% vs -13%, -10%, 10%) in LV end-diastolic volume, LV end-systolic volume, and LV ejection fraction, respectively, compared with baseline versus patients with an SDI <10% (p <0.01). Mean acquisition and analysis duration of single-patient RT3DE was 8 minutes (range 6 to 13). Interobserver variabilities of LV end-systolic volume and SDI were 5% and 11%, respectively. In conclusion, RT3DE provides accurate identification of reverse volumetric LV remodeling after CRT. From these accurate volumetric data, RT3DE provides more intuitive assessment of dyssynchrony and response to CRT as a simple, reproducible, and fast technique. CRT can be individually tailored using RT3DE and seems very effective in patients with heat failure with real-time 3-dimensional echocardiographic evidence of dyssynchrony.

Frequency of Conduction Abnormalities After Transcatheter Aortic Valve Implantation With the Medtronic-CoreValve and the Effect on Left Ventricular Ejection Fraction

New conduction abnormalities occur frequently after transcatheter aortic valve implantation (TAVI). The relation between new conduction disorders and left ventricular (LV) systolic function after TAVI is unknown. The purpose of the present prospective, single-center study was to investigate the effect of TAVI on LV systolic function in relation to TAVI-induced conduction abnormalities. A total of 27 patients had undergone electrocardiography and transthoracic echocardiography the day before and 6 days after TAVI with the Medtronic-CoreValve system. The LV ejection fraction (EF) was calculated using the biplane Simpson method. The systolic mitral annular velocities and longitudinal strain were measured using speckle tracking echocardiography. After TAVI, 18 patients (67%) had new conduction abnormalities; 4 (15%) had a new paced rhythm and 14 patients (52%) had new left bundle branch block. In the patients with new conduction abnormalities, the EF decreased from 47 ± 12% to 44 ± 10%. In contrast, in those without new conduction abnormalities, the EF increased from 49 ± 12% to 54% ± 12%. The change in EF was significantly different among those with and without new conduction abnormalities (p <0.05). In patients without new conduction abnormalities, an improvement was found in the systolic mitral annular velocities and longitudinal strain (p <0.05). In contrast, in patients with new conduction abnormalities, the changes were not significant. In conclusion, the induction of new conduction abnormalities after TAVI with the Medtronic-CoreValve was associated with a lack of improvement in LV systolic function.

Quantification of Left Ventricular Systolic Dyssynchrony by Real-Time Three-Dimensional Echocardiography

OBJECTIVE To assess real-time 3-dimensional echocardiography (RT3DE)-derived left ventricular (LV) systolic dyssynchrony parameters: (1) normal values, (2) characteristics in patients with heart failure (HF) and a wide or narrow QRS complex, (3) interobserver and intraobserver variability with current state of the art RT3DE hardware and software technology, and (4) incremental value in patients with HF who receive cardiac resynchronization therapy (CRT). METHODS The study involved 84 patients with HF (mean age 54 +/- 15 years, 50 men) and 60 healthy volunteers (mean age 41 +/- 15 years, 36 men). Semiautomated LV endocardial border tracking was used to calculate regional time-to-minimum systolic volume and to generate parametric maps and the systolic dyssynchrony index (SDI), defined as the standard deviation of time-to-minimum systolic volume of the 16 LV segments expressed in percentage of R-R duration. RESULTS The volume rate of the RT3DE datasets in patients with HF was 31 +/- 9 Hz (range 15-42 Hz). The normal value of the SDI was 4.1% +/- 2.2% (range <1.0%-8.9%). Patients with HF had a larger SDI (13.4% +/- 8.1%, P < .001). There was only a weak correlation (r2 = 0.07, P < .05) between the QRS duration and the SDI. Interobserver interclass correlation and variability of the SDI depended on image quality (good: 0.993 and 9%, moderate: 0.907 and 16%, respectively). Interobserver agreement for the identification of the most delayed LV segment depended on image quality (good: 90%, moderate: 76%). Thirty-nine patients underwent CRT. At the 12-month follow-up, LV volumetric responders had a significant reduction in the SDI (16.3% +/- 3.3% to 7.7% +/- 2.4%, P < .001). CONCLUSION With state of the art technology, RT3DE allows reproducible assessment of LV systolic dyssynchrony, which may be useful to identify potential responders to CRT.