Contrast-enhanced versus non-enhanced three-dimensional echocardiography of left ventricular volumes.

BACKGROUND: In three-dimensional echocardiography (3DE), individual endocardial trabeculae are not clearly visible necessitating left ventricular (LV) volumes to be measured by tracing the innermost endocardial contour. Ultrasound contrast agents aim to improve endocardial definition, but may delineate the outermost endocardial contour by filling up intertrabecular space. Although measurement reproducibility may benefit, there may be a significant influence on absolute LV volume measurements. METHODS: Twenty patients with a recent myocardial infarction and good ultrasound image quality underwent 3DE using the TomTec Freehand method before and during continuous intravenous contrast infusion. LV volumes were measured offline using TomTec Echo-Scan software. RESULTS: The use of contrast enhancement increased end-diastolic (110+/-35 vs. 144+/-53 ml; p<0.01) and end-systolic volume measurements (68+/-31 vs. 87+/-45 ml; p<0.01) significantly compared with non-contrast; the ejection fraction remained unchanged (40+/-13 vs. 41+/-14%, p=NS). Measurement reproducibility did not improve significantly, however. CONCLUSION: Volumes measured by 3DE are significantly larger when ultrasound contrast is used. Possibly, intertrabecular space comprises a substantial part of the LV cavity. In the presence of an adequate apical acoustic window, ultrasound contrast does not improve LV volume measurement reproducibility. (Neth Heart J 2008;16:47-52.).

The left bundle branch block revised with novel imaging modalities.

Left bundle branch block (LBBB) is related to abnormal cardiac conduction and mechanical asynchrony and is associated with hypertension and coronary artery disease. Improved evaluation of left ventricular (LV) mechanical asynchrony is needed, because of the increasing number of patients with LBBB and heart failure. In this paper, we describe tissue Doppler imaging (TDI), strain (rate) imaging and tissue tracking in LBBB patients. A variety of patterns of mechanical activation can be observed in LBBB patients. A recent development, referred to as tissue synchronisation imaging, colour codes TDI time-to-peak systolic velocities of segments and displays mechanical asynchrony. Furthermore, real-time 3D echocardiography provides new regional information about mechanical asynchrony. Contained in an LV model and projected on a bull's eye plot, this modality helps to display the spatial distribution of mechanical asynchrony. Finally, segmental time-to-peak circumferential strain curves, produced by cardiac magnetic resonance imaging, provide additional quantification of LV mechanical asynchrony. Effects of LBBB on regional and global cardiac function are impressive, myocardial involvement seems to play a role and with the help of these novel imaging modalities, new insights continue to develop.

Assessment of the left atrial appendage mechanical function by three-dimensional echocardiography.

AIMS: We evaluated the feasibility of three-dimensional echocardiography, in the assessment of left atrial appendage (LAA) function. METHODS AND RESULTS: Forty-five patients underwent multiplane transoesophageal echocardiography. In addition to Doppler and two-dimensional echocardiography, data for three-dimensional echocardiography reconstruction were obtained during transoesophageal echocardiography. Left atrial appendage ejection fraction based on three-dimensional echocardiography volume measurements (EFv) and two-dimensional echocardiography area measurements (EFa), coupled with other echocardiographic data, were related to left atrial appendage late peak emptying velocity, a frequently used indicator of left atrial appendage function. Multiple regression analysis has revealed a significant association of peak emptying velocity with EFv (P<0.0001), spontaneous echocardiographic contrast (P=0.001), tricuspid regurgitation (P=0.03) and left ventricular hypertrophy (P=0.05). No significant relation was observed between peak emptying velocity and EFa, presence or absence of atrial fibrillation, left ventricular dysfunction, mitral stenosis and insufficiency, left atrial dilatation, pulmonary venous peak systolic, diastolic and peak reverse flow velocity at atrial contraction as well as left atrial appendage volumes derived from two-dimensional echocardiography and three-dimensional echocardiography. In a simple linear correlation, the degree of association between peak emptying velocity and EFv was higher as between peak emptying velocity and EFa (r=0.7 vs 0.4, both P<0.001). Observer variabilities for calculating EFv were considerably lower than for two-dimensional echocardiography derived EFa. Ejection fractions determined by two-dimensional echocardiography area measurements at 45 degrees, 90 degrees and 135 degrees cutplane angulations were related to EFv only at 135 degrees. CONCLUSIONS: Left atrial appendage ejection fraction calculation by three-dimensional echocardiography is feasible, more accurate than by two-dimensional echocardiography and has lower observer variability. Furthermore, an optimal cutplane angulation of the left atrial appendage view at 135 degrees has been demonstrated.

Quantitative assessment of mechanical prosthetic valve area by 3-dimensional transesophageal echocardiography.

OBJECTIVE: The goal of this study was to assess the geometric orifice area of mechanical valve prostheses by transesophageal 3-dimensional echocardiographic planimetry. METHODS AND RESULTS: Currently used Doppler methods for prosthetic assessment (orifice area-Doppler) were compared with 3D planimetry for orifice area (orifice area-3D) and with manufacturer's values (orifice area-manufacturer) for the corresponding prosthesis types and sizes and with historical controls provided by Doppler literature (orifice area-literature). Twenty-four mechanical valve prostheses (in 22 patients) were studied: 13 in mitral position and 11 in aortic position. Orifice area-manufacturer, orifice area-Doppler, orifice area-literature, and orifice area-3D were 3.6 +/- 1.1 cm(2), 2.3 +/- 0.9 cm(2), 2.4 +/- 0.9 cm(2), and 2.6 +/- 0.7 cm(2), respectively. Orifice area-manufacturer values were significantly larger. Correlation coefficients between orifice area-3D and orifice area-manufacturer, and between orifice area-3D and orifice area-Doppler and orifice area-literature were 0.83, 0.90, and 0.73, respectively (all P < .0001). CONCLUSION: Three-dimensional transesophageal echocardiography is feasible and has good correlation with orifice area-Doppler (in aortic position) and good correlation with orifice area-manufacturer (in aortic and mitral positions) methods.

Influence of heart rate, respiration and recipient atrial contraction on pulsed wave transmitral Doppler flow indices in orthotopic heart transplant recipients.

AIMS: The study set out to assess the relative contributions of donor heart rate, respiration and recipient atrial contraction on the mean of pulsed wave transmitral Doppler flow indices in orthotopic heart transplant recipients. This would provide information on the theoretical usefulness of pacemaker synchronization of recipient atrial contraction, as well as on the validity of certain strategies used for pulsed wave Dopper analysis of diastolic left ventricular function, which have excluded beats based on recipient atrial contraction timing. METHODS: Thirty two consecutive patients undergoing orthotopic heart transplantation in our centre were prospectively studied. The following Doppler indices were analysed: peak early diastolic velocity (E) and its area under the Doppler curve (TVIE), diastolic velocity after donor atrial contraction (A) and its area under the curve (TVIA), the total area under the curve (TVI), the isovolumic relaxation period (IVR), the diastolic filling period, the normalized peak filling rate and the pressure half time. RESULTS: Only 81 out of 347 recordings (23%) allowed analysis of the recipient P wave and thus recipient atrial contraction timing, heart rate and the respiration phase in 22 patients for a total of 1579 beats. The isovolumic relaxation period, E, pressure half time and TVIA are not influenced by donor heart rate. For the isovolumic relaxation period, E, TVI and TVIE, respiration contributes as much as recipient atrial contraction timing to beat-to-beat variation. Pressure half time, the diastolic filling period and peak filling rate were not affected by respiration. TVI was not affected by recipient atrial contraction timing. CONCLUSION: With respect to analysis of diastolic function, exclusion of beats based on recipient atrial contraction timing is invalid for the isovolumic relaxation period. E, TVI and TVIE, since these are equally influenced by respiration. Since TVI was not affected by recipient atrial contraction timing, pacemaker synchronization of donor and recipient atria is not expected to be useful in patients with left ventricular diastolic dysfunction.

Auditory vertex potential in children: a cognitive hypothesis.

In children the early N1P2 response generated by an auditory oddball paradigm is a compound negative potential with distinctive 165-ms temporal and 240-ms frontocentral components. As this configuration differs considerably from the adult response, it may be assumed that neural systems engaged in auditory attentional processes differ with age. It is argued that the auditory vertex potential might index frontal lobe development and matching mechanisms. In combination with EEG spectral data this cognitive parameter could initiate an alternative approach to the evaluation and research of learning and attention deficit disorders.

[Rapidly progressive aortic insufficiency in a female patient with rheumatoid arthritis]. / Snel progressieve aorta-insufficiëntie bij een patiënte met ernstige reumatoïde artritis.

In a 23-year-old woman with severe rheumatoid arthritis, a rapidly progressive aortic regurgitation (onset within 2 years) was observed. She had a high IgM rheumatoid factor titre and nailfold lesions. The differential diagnosis from infectious endocarditis was difficult. The patient's aortic valve was replaced with a St. Jude mechanical prosthesis. The aortic valve was tricuspid with thick sclerotic cusps and sterile ulcerations and vegetations on the left and right coronary cusps. Histopathologic examination showed hyaline degenerative changes and plasma cell infiltrates in the stroma of the cusps, associated with rheumatoid arthritis. In the literature, aortic regurgitation is associated with longstanding rheumatoid arthritis, subcutaneous nodules, a high IgM rheumatoid factor titre and (or) signs of vasculitis.

Pulsed-wave transmitral Doppler do not diagnose moderate acute rejection after heart transplantation.

The value of pulsed-wave transmitral Doppler for the diagnosis of moderate acute rejection was examined in a total of 347 Doppler recordings obtained in 32 consecutive cardiac allograft recipients. Serial Doppler examinations (median, 11 per patient; range, 1 to 23) were performed simultaneously with endomyocardial biopsies from the first week after heart transplantation to a follow-up of 186 days (median; range, 10 to 395 days after transplantation). Pulsed-wave transmitral Doppler did not allow noninvasive diagnosis of moderate acute rejection in individual patients. Peak filling rate normalized for mitral stroke volume, early diastolic velocity, and mean diastolic velocity were significantly increased, whereas diastolic filling period was decreased during moderate acute rejection compared to other biopsy classes. The wide overlap of measurements in individual recipients with or without rejection may be due, however, to a variety of hemodynamic factors after transplantation affecting diastolic function, which are superimposed on the restrictive left ventricular filling pattern caused by persistent mild acute rejection and left ventricular hypertrophy. These hemodynamic factors include pulmonary hypertension, perioperative ischemia, reperfusion injury, and changes in both blood pressure and loading conditions caused by hypertension and its treatment. Differences between studies with regard to the detection of moderate acute rejection by transmitral Doppler may be caused by chance, because most studies were relatively small. Differences in methods, patient selection, duration of follow-up, prevalence of hypertension and left ventricular hypertrophy, and differences in antihypertensive drug regimens may also play a role. Furthermore differences in the incidence of mild acute rejection, its treatment, and the type of maintenance immunosuppressive regimen used may have influenced the outcome of these studies considerably.

Changes in left ventricular function and wall thickness in heart transplant recipients and their relation to acute rejection: an assessment by digitised M mode echocardiography.

OBJECTIVE: Assessment of changes in left ventricular diastolic function and wall thickness after heart transplantation to verify whether these changes predicted acute rejection assessed by endomyocardial biopsy. DESIGN: Follow up according to a predefined protocol of consecutive patients from the first week after transplantation. SETTING: Heart transplantation unit of the Thoraxcentre, University Hospital Rotterdam Dijkzigt, The Netherlands. PATIENTS: All 32 patients undergoing orthotopic heart transplantation from 1 January 1989 to 31 March 1990 were examined. Two were excluded from the analysis. Patients were treated with cyclosporin and low dose steroids. MAIN OUTCOME MEASURES: Data obtained by digitised M mode echocardiography were compared with the results of endomyocardial biopsy (Billingham classification). Mean values for left ventricular wall thickness, internal dimension, and their standardised rates of change and fractional shortening were determined from 4-6 consecutive expiratory beats. Mean values and individual trends during follow up were also investigated for each ultrasound variable. The results of these average values were compared with values in a group of 10 healthy volunteers. RESULTS: Median follow-up was 177 days (range 10-399). Two hundred and sixty three consecutive M mode studies were examined in relation to concurrent biopsy results. No significant differences were observed between the ultrasound variables at the time of moderate acute rejection (Billingham class 2, n = 37) and other biopsy classes (n = 226). Nor did changes in individual patients predict (moderate) acute rejection episodes. Twenty six of the 30 patients had an abnormal (slow) left ventricular relaxation pattern throughout follow up. CONCLUSIONS: Digitised left ventricular M mode echocardiography did not predict the presence of acute rejection. In most patients there was a persistent slow left ventricular relaxation pattern.

Immune response to hepatitis B vaccine in drug addicts.

Drug addicts are at high risk of hepatitis B infection and are therefore candidates for vaccination against hepatitis B. Since drug addicts may have an impaired immune response, and low compliance for therapy extending over several months, we evaluated a vaccination scheme according to the instruction of the manufacturer (HB- Vax 20 micrograms at zero, one and six months) in drug addicts using daily methadone (Group M), in drug addicts in residential detoxification programmes (Group D), and in treatment centre staff who were seronegative for hepatitis Bs (Group S). All 23 controls and 20 of 21 of Group D completed the vaccination programme, in contrast to 14 of 24 in Group M. Anti-HBs developed in 91 per cent of Group S and in all addicts tested at six months. Anti-HBs titres at seven months were higher than 100 RIA units in 55 per cent of Group S, in 94 per cent of Group D and in 44 per cent of Group M. We conclude that HB- Vax induces production of anti-HBs equally well in drug addicts and in controls: a shorter-duration vaccination schedule might be more appropriate for 'non-captive' drug addicts living outside therapeutic communities.