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Background: Despite increasing availability of three-dimensional imaging modalities for estimating right ventricular (RV) size, linear and two-dimensional measures of RV size are the most universally accessible clinical methods. Right ventricular end-diastolic area (RVED area) is known to identify pulmonary pathologies and have prognostic value for cardiovascular mortality in various disease states. To date, there is a paucity of adequately powered studies to define gender- and ethnicity-related differences in normal RVED area. Therefore, we derived gender-based normative values for echocardiographic measurements of RVED area, in a large bi-racial cohort of young adults. Methods: Healthy young adults participants (n = 2088) in the Coronary Artery Risk Development in Young Adults (CARDIA) study, aged 23–35 years, at the time of echocardiogram, were evaluated. RVED area was stratified according to gender and race. The contributions of clinical, allometric and left heart morphology and function to the variability in RVED area were determined. Results: RVED area in males was significantly larger than in females of similar age, but whites had similar values compared to same-gender blacks. RVED area for men and women of >24.7 cm2 and 20.7cm2, or RVED area indexed to BSA (cm2/m2) of >12.6 and >11.7, respectively, are at the 97.5th percentile of normal values. RVED area correlated significantly with left ventricular volume and left atrial size. Lung capacity measured as FVC showed significant body size adjusted correlation with RVED area only in black males. Conclusions: This study provides normative values for echocardiographically defined RV end-diastolic area, and highlights the necessity to use gender-specific normative values. (Echocardiography 2011;28:142-149)

BACKGROUND We examined the relationship of left ventricular (LV) end-systolic meridional wall stress (LVESS), a measure of LV afterload, with race, gender, other cardiovascular risk factors and LV mass in 3,994 young adults in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. METHODS From transthoracic echocardiography, LVESS was derived from LV internal dimension and posterior wall thickness and systolic blood pressure (BP). RESULTS Adjusted LVESS was significantly greater in black men versus women (59.0 vs. 54.8 dynes/cm, P < 0.01) and in white men versus women (59.0 vs. 55.4 dynes/cm(2), P < 0.01), but did not differ in comparing whites versus blacks either in men or women. In multiple regression analyses, age and LV mass were inversely (P < 0.01) and height was positively (P < 0.01) associated with LVESS. The overall variance of LVESS explained by the models in each race-sex subgroup was low (R(2) less than 0.03), suggesting that standard risk factors contribute little to determining LVESS in young adults. Over a 15-year follow-up period, LVESS, after the adjustment for covarieties, was not associated with the incidence of coronary heart disease (CHD) and cardiovascular disease (CVD) events. CONCLUSION LVESS may not be a useful marker of cardiovascular risk in young adults; further study is needed to determine whether other echocardiographic measures may be more useful predictors.

BACKGROUND We recently reported the prevalence of aortic regurgitation (AR) by Doppler echocardiography (echo) in obese subjects to be higher than in some previous reports. OBJECTIVE To describe the prevalence of AR in an obese population not taking anorexigens as a function of demographic characteristics, cardiovascular risk factors, and other potential predictors. METHODS In 539 adult subjects, cardiovascular status was evaluated by medical history, physical examination, and Doppler echocardiograms performed according to a standardized imaging protocol. Echocardiographic readers were blinded as to each subject's medical and medication histories. Associations of AR with demographic and comorbid factors were examined. RESULTS Subjects had a mean (+/- SD) body mass index (BMI) of 35 +/- 7 kg/m2, and were predominantly white (87.6%), females (74%), with a mean age of 47 +/- 12 years. AR by Food and Drug Administration criteria (> or =mild) was present in 4.1% of the subjects. Covariates significantly associated with AR were increasing age (P < 0.001), presence of a history of hypertension (P = 0.001), left ventricular (LV) internal dimensions (P < 0.005), and tricuspid and mitral regurgitation grade (P < 0.001). CONCLUSIONS Clinical and Doppler echo evaluation of a large, predominantly obese, adult population revealed that AR was more prevalent than in some previous reports and was highly correlated with increased age, presence of a history of hypertension, LV internal dimensions, tricuspid and mitral regurgitation.

Objective: The relationship of intravascular ultrasound (IVUS)-derived measurements of atherosclerotic plaque to various coronary artery disease (CAD) risk factors is not well known. The purpose of this study was to examine the relationship of percent coronary luminal stenosis by IVUS to other IVUS measures of CAD, as well as the relationship of common IVUS measures of CAD to traditional CAD risk factors. We hypothesized that one or more IVUS measures of CAD might relate more strongly to CAD risk factors than does percent luminal coronary stenosis. Methods: The records of 897 consecutive patients (57% men, mean age 62 years) who underwent IVUS investigation of their coronary arteries from 1996 through 2001 were retrospectively reviewed. IVUS was performed using a 20-MHz probe (Jomed, Rancho Cordoba, CA) and a manual pull-back technique to image the coronary arteries. Coronary artery remodeling ratio—i.e., the ratio of coronary lesion external elastic membrane cross-sectional area (EEM CSA) to proximal reference artery EEM CSA; plaque burden—i.e., plaque plus media CSA divided by EEM CSA; calcium arc; and percent stenosis of luminal cross-sectional area were measured by a single reader. Results: Percent area stenosis, the most commonly used IVUS parameter, did not correlate with the other three IVUS-derived parameters, nor was it related to any of the CAD risk factors considered. In contrast, remodeling ratio was directly correlated with plaque burden (r = 0.22, P < 0.001), but inversely related to calcium arc (r =−0.13, P = 0.01). IVUS plaque burden was significantly correlated with male gender (P < 0.0001) and diabetes mellitus (DM) (P = 0.003). In multivariate analyses including age, gender, and CAD risk factors, plaque burden was significantly associated with age, male gender, and DM, but not with chronic renal failure, hypertension, or hypercholesterolemia. The multivariate model also revealed that the calcium arc was significantly associated with male gender and age. These IVUS findings provide anatomic documentation that the traditional CAD risk factors relate more strongly to plaque burden than to percent coronary arterial luminal narrowing.

Background: Prompt detection of atherosclerosis (ATH) may profoundly impact therapy and patient outcome. During transthoracic echocardiography (TTE), subcostal views may suggest abdominal (ABD) aortic (AO) ATH, but this diagnosis may be inaccurate due to suboptimal images, which may in part relate to use of nonlinear probes. Therefore, we investigated the accuracy of TTE assessment of ABD AO ATH relative to transesophageal (TEE) AO images. Methods: Routine clinical TTE and TEE studies of 100 patients (44 men), aged 30–92 years old, were reviewed retrospectively and blindly. ABD AO ATH by TTE was graded qualitatively as grade (GR) 0 = smooth wall surface; GR 1, 2, and 3 = mild, moderate, and severe irregularities, respectively; and GR 4 = mobile/complex plaque. TEE images were graded quantitatively as the maximal intimal-medial, or plaque thickness, imaged in the AO arch or descending AO, as: GR 0 ≤ 1.5 mm, GR 1 = 1.5–2.4 mm, GR 2 = 2.5–4 mm, GR 3 = >4 mm, or GR 4 = mobile/complex plaque >4 mm. TTE ability to detect the presence (>GR 0) of ABD AO ATH on TEE was measured in terms of sensitivity (SN), specificity (SP), positive (PPV) and negative (NPV) predictive accuracy—in patients with adequate and suboptimal images—compared to TEE. Results: TTE image quality was adequate in 75 patients and suboptimal in 25. SP and PPV of grading ATH by TTE were directly related to grading by TEE; however, SN and NPV demonstrated an inverse relationship with increasing grading of ATH. TTE correlated with TEE grading with an r = 0.42 (P = 0.0001) for patients (n = 75) with adequate TTE and r = 0.32 (P = 0.001) for all patients (n = 100), including those with suboptimal TTE images. Conclusion: Routine TTE imaging is usually correct in predicting ATH on TEE, but with modest error, it should generally not be relied on as a definitive test for ATH. Adequate image quality improves the correlation of TEE and TTE grading of ABD ATH, and more severe ATH on TTE is more predictive of ATH on TEE.

Recent findings suggest that systemic artery endothelial function is associated with the preclinical phase of vascular disease and related to traditional atherosclerosis risk factors. Brachial artery diameter changes in response to hyperemia have been proposed recently as a noninvasive tool to assess endothelial function. To evaluate the reproducibility of brachial artery diameter measurements using ultrasound, we studied 12 healthy subjects (eight men and four women, mean age 37 +/- 9 years). An ATL HDI 3000 machine with a 5- to 10-MHz broadband transducer was used to image the right brachial artery at rest, approximately 4 cm above the elbow. Gray scale ultrasound and color Doppler long-axis images were recorded. Brachial arterial outer diameter (i.e., from anterior adventitia to posterior adventitia) and inner diameter (i.e., from anterior lumen-intima interface to posterior lumen-intima interface) were measured in each subject by two observers. An offline analysis system was used to make measurements at end-diastole from four cardiac cycles. Interobserver and intraobserver measurement variabilities (technical error rates) for brachial artery inner diameter were excellent, ranging from 2.5% to 3.8%. However, interobserver technical error rates for outer diameter measurements were significantly greater than those for inner diameter measurements, ranging from 16.3% to 22.1% (P < 0.001), presumably related to the difficulty in accurately defining the adventitial lines. There were no significant differences in interobserver and intraobserver variability for measurements made using gray scale and color Doppler-aided techniques. We conclude that interobserver and intraobserver reproducibility for brachial artery inner diameter measurements made from ultrasound images is excellent.

With the advent of transgenic technology, it has become increasingly important to find a method for evaluating left ventricular (LV) anatomy and function in intact wild type, intervened, and transgenic mice. Mice are 1/10th the size of rats, and have body masses of 10-60 g, LV masses of 40-150 mg, LV wall thicknesses of 0.5-2 mm, and LV internal dimensions of 1-3 mm. Although the murine LV has been imaged by transthoracic (TTE) two-dimensional directed M-mode echocardiography, we explored the use of intravascular ultrasound (IVUS) catheters, with imaging from various positions, to see if better two-dimensional images of the LV could be obtained by IVUS than TTE. Eight normal mice were anesthetized using pentobarbital or avertin. The mice were studied using a commercially available IVUS system (Endosonics, Inc.). Two IVUS catheters (3.5 and 5.0 Fr) with 20-MHz multielement array transducers were used. Each catheter had a 4.0-mm imaging depth of field in all directions (360 degrees ) from the mid-point of the catheter core. Multiple imaging approaches were attempted: transesophageal (TEE); transjugular (TJ); transperitoneal (TP); and open chest, from both epicardial surface (Ep) and via direct LV puncture. TEE and TJ approaches afforded insufficient depth of field to image the entire LV in cross section. TP and Ep approaches resulted in poor images, related both to inadequate depth of field and to relatively small sector angles subtended by imaging elements. LVP (intracavitary imaging) was capable of satisfactorily imaging the LV epicardium, but was unable to image the endocardium, probably because the latter was within the 1.9-mm "ringdown" catheter artifact. All IVUS approach studies lacked sufficient temporal resolution (10 frames/sec) to reliably display systolic and diastolic frames necessary for evaluation of LV function. In contrast, as previously reported, transthoracic two-dimensionally directed M-mode echocardiograms have sufficient temporal and spatial resolution to permit accurate estimates of LV mass and systolic function. Currently, IVUS catheter-based approaches are not feasible for imaging murine LV anatomy and function. Limitations include: (1) inadequate temporal resolution might be improved by ECG gating; (2) limited depth of field possibly resolvable by lower frequency transducers; and (3) relatively large catheter size. (ECHOCARDIOGRAPHY, Volume 13, November 1996)

Color Doppler flow mapping of the regurgitant jet is frequently used as a means of assessing the severity of valvular regurgitation. Although convenient, this method of assessing valvular regurgitation is subject to a number of hemodynamic and technical factors that may limit its accuracy. Variations in hemodynamic and structural factors such as orifice size, jet geometry, receiving chamber constraints, afterload, fluid viscosity, heart rate, and cardiac output may have profound effects on the measured regurgitant jet area. Variations in scanning and machine factors, such as scanning direction, Doppler angle, frame rate, color display algorithms, pulse repetition frequency (PRF), system gain, packet size, carrier frequency, wall filter, and transmit power have been shown to alter the measured regurgitant jet area significantly. Despite these limitations, color flow Doppler provides a relatively reliable noninvasive method for semiquantitative assessment of valvular regurgitation. Obviously, standardization of the design and application of the various available color mapping algorithms, as well as other machine and hemodynamic factors, would help provide more reliable and reproducible quantitative information about the degree of valvular insufficiency.