Predictors of Exercise Capacity in Dilated Cardiomyopathy with Focus on Pulmonary Venous Flow Recorded with Transesophageal Eco-Doppler

The aim of this study was to clarify the relative contribution of elevated left ventricle (LV) filling pressure (FP) estimated by pulmonary venous (PV) and mitral flow, transesophageal Doppler recording (TEE), and other extracardiac factors like obesity and renal insufficiency (KI) to exercise capacity (ExC) evaluated by cardiopulmonary exercise testing (CPX) in patients with dilated cardiomyopathy (DCM). During the CPX test, 119 patients (pts) with DCM underwent both peak VO2 consumption and then TEE with color-guided pulsed-wave Doppler recording of PVF and transmitral flow. In 78 patients (65%), peak VO2 was normal or mildly reduced (>14 mL/kg/min) (group 1) while it was markedly reduced (≤14 mL/kg/min) in 41 (group 2). In univariate analysis, systolic fraction (S Fract), a predictor of elevated pre-a LV diastolic FP, appeared to be the best diastolic parameter predicting a significantly reduced peak VO2. Logistic regression analysis identified five parameters yielding a unique, statistically significant contribution in predicting reduced ExC: creatinine clearance < 52 mL/min (odds ratio (OR) = 7.4, p = 0.007); female gender (OR = 7.1, p = 0.004); BMI > 28 (OR = 5.8, p = 0.029), age > 62 years (OR = 5.5, p = 0.03), S Fract < 59% (OR = 4.9, p = 0.02). Conclusion: KI was the strongest predictor of reduced ExC. The other modifiable factors were obesity and severe LV diastolic dysfunction expressed by blunted systolic venous flow. Contrarily, LV ejection fraction was not predictive, confirming other previous studies. This has important clinical implications.

Image-Free Ultrasound Blood-Flow Monitoring Circuit System with Automatic Range-Gate Positioning Scheme: A Pilot Study

This work proposes a proof-of-concept ultrasound blood-flow-monitoring circuit system using a single-element transducer. The circuit system consists of a single-element ultrasonic transducer, an analog interface circuit, and a field-programmable gate array (FPGA). Since the system uses a single-element transducer, an ultrasound image cannot be reconstructed unless scanning with mechanical movement is used. An ultrasound blood-flow monitor basically needs to acquire a Doppler sample volume by positioning a range gate at a vessel region on a scanline. Most recent single-transducer-based ultrasound pulsed-wave Doppler devices rely on a manual adjustment of the range gate to acquire Doppler sample volumes. However, the manual adjustment of the range gate depends on the user’s experience, and it can be time consuming if a transducer is not properly positioned. Thus, automatic range-gate-positioning is more desirable for image-free pulsed-wave Doppler devices. This work proposes a circuit system which includes a new automatic range-gate-positioning scheme. It blindly tracks the position of a blood vessel on a scanline by using the accumulation of Doppler amplitude deviations and a hysteresis slicing function. The proposed range-gate-positioning scheme has been implemented in an FPGA for real-time operation and is based on addition-only computations, except for filter parts to reduce the complexity of computation in the hardware. The proposed blood-flow-monitoring circuit system has been implemented with discrete commercial chips for proof-of-concept purposes. It uses a center frequency of 2 MHz and a system-clock frequency of 20 MHz. The FPGA only utilizes 5.6% of slice look-up-tables (LUTs) for implementation of the range-gate-positioning scheme. For measurements, the circuit system was utilized to interrogate a customized flow phantom model, which included two vessel-mimicking channels. The circuit system successfully acquired Doppler sample volumes by positioning a range gate on a fluid channel. In addition, the estimated Doppler shift frequency shows a good agreement with the theoretical value.

The Use of Compression Sonoelastography in Multiparametric Ultrasound Examination in Cases of Benign Ovarian Formations

Properly diagnosed benign ovarian formations are a condition for appropriate treatment choice. Qualitative assessment of signs detected by multiparametric ultrasound, including compression elastography, is highly effective in the differential diagnosis of benign ovarian formations. Our study became especially relevant for women in the reproductive period since the correct diagnosis influenced the choice of surgical treatment in order to preserve the ovarian reserve. The detailed sonographic aspect of these formations in B-mode, Doppler mode and compression sonoelastography mode is analyzed in the article. Color Flow Mapping, power Doppler and pulsed wave Doppler were used to study blood vessels. Pulsed wave Doppler characterized blood flow quantitatively. Color Flow Mapping was used to determine vessels localization, and power Doppler was used to provide a detailed qualitative assessment of blood flow loci. Elastotype according to the Ueno scale as a qualitative feature and Strain Ratio (coefficient of deformation) as a quantitative indicator were determined for all types of benign ovarian formations. Serous and mucinous cystadenomas were found to belong to elastotypes 0 and I according to the Ueno scale, the papillary component of serous superficial papillomas was mapped as elastotype I and II, fibroids predominantly belonged to elastotype II and III, mature teratoma appertained to elastotypes IV and V. Quantitative coefficient of deformation for all benign ovarian formations ranged from 0.63 to 24.9. According to our results, ultrasound examination of ovarian formations is an accurate and highly informative method for stratification of risks in accordance with the O-RADS classification.

Evaluation of the diastolic functions of the heart in patients with heart failure after Cardiac Resynchronization Therapy (CRT)

Improvement in systolic functions after CRThas been well-established, but the effect on Left Ventricular (LV) diastolic functions is variable and not well established. The aim of this study is to analyze the improvement in diastolic functions of the heart after CRT. Total 67 cases of Heart Failure (HF) eligible for CRT (mean age, 62.5 ± 11.73 years; 54 males and 13 females) with Left Ventricular Ejection Fraction (LVEF) ≤35% or New York Heart Association (NYHA) Class II, III / Ambulatory IV (IVA) were included in the study. LVEF, pulsed-wave Doppler (PWD) derived transmitral filling indices (E and A wave velocities, E/A ratio), and peak early diastolic longitudinal myocardial velocity (E´) wave by tissue doppler were measured pre and post CRT and were compared. Left Ventricular Ejection Fraction (LVEF) increased &#62;5% (responders) in 42 of 67 patients (62.6%) which was also associated with a reduction in pulsed-wave Doppler (PWD) derived indices that is E velocity, E/A ratio and E/E’ ratio while in non-responders (LVEF&#60;5%) the E velocity, E/A ratio, E’ did not show significant change but E/E’ reduced significantly after CRT. Left Ventricular Diastolic functions improved significantly after CRT in responders but not in non responders.

A preliminary study on an image analysis based method for lowest detectable signal measurements in Pulsed Wave Doppler ultrasounds

<span lang="EN-GB">Nowadays, Doppler system performance evaluation is a widespread issue because a shared worldwide standard is still awaited. Among the recommended Doppler test parameters, the lowest detectable signal could be considered mandatory in Quality Control (QC) protocols for Pulsed Wave (PW) Doppler. Such parameter is defined as the minimum signal level that can be clearly distinguished from noise and therefore, it is considered as related to PW Doppler sensitivity. The present study focuses on proposing and validating a novel image analysis based method for the estimation of the Lowest Detectable Signal in the spectrogram image (LDS_IMG), namely Automatic Doppler Sensitivity Measurement Method (ADSMM), as well as to compare its results with the outcomes retrieved from the Naked Eye Doppler Sensitivity Method (NEDSM), based on the mean judgment of three independent observers. Data have been collected from a Doppler flow phantom, through three ultrasound systems for general purpose imaging, equipped with two linear array probes each and with two configuration settings. Results are globally compatible among the proposed methods, US systems and settings. Further studies could be carried out on a higher number of US diagnostic systems, Doppler frequencies and observers, as well as with different probe and phantom models.</span>