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Regional Wall Motion (regional + wall_motion)

Distribution by Scientific Domains

Medical Sciences	87%

Selected Abstracts

Right Ventricular Function in Congenital Heart Defects Assessed by Regional Wall Motion

CONGENITAL HEART DISEASE, Issue 3 2010
FSCAI, Michael R. Nihill MB
ABSTRACT Objectives., To develop a simple method to assess right ventricular function by angiography. Background., Conventional methods of evaluating right ventricular function are inaccurate, cumbersome, and expensive. Methods., We analyzed biplane right ventricular angiograms taken in the posterior,anterior and lateral projections using software to measure right ventricular volumes and regional wall motion in 78 patients with normal hearts (n = 29), atrial septal defects (ASD n = 13), pulmonary valve stenosis (PVS n = 21), and postoperative atrial switch patients (n = 15). We also measured the shortening fraction (SF) from the midtricuspid annulus to the septum and correlated various angiographic measurements with the right ventricular (RV) ejection fraction. Results., The volume-overloaded patients (ASD) had larger end diastolic volumes and increased SF compared with normal patients, while the pressure-loaded patients (PVS) had normal volumes and SF. The postoperative atrial switch patients had decreased systolic function and increased end diastolic volume. The SF for all of the patients correlated with the ejection fraction (r= 0.785, P, .0001). Conclusions., A simple measurement of the end diastolic and end systolic distance from the midtricuspid annulus to the septum (SF) provides a good index of RV function by angiography and correlates well with RV ejection fraction. [source]

Motion visualization of human left ventricle with a time-varying deformable model for cardiac diagnosis

COMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 2 2001
Soo-Mi Choi
Abstract We present a time-varying deformable model to visualize and analyze the motion of the left ventricle from a time series of 3-D images. The model is composed of a non-rigid body that deforms around a reference shape obtained from the previous time step. At each time step, the position and orientation of the left ventricle are extracted from the feature points of images. This information gives the position and orientation of the coordinate system attached to the non-rigid body. To compute a dense non-rigid motion field over the entire endocardial wall of the left ventricle, we introduce a 3-D blob finite element and Galerkin interpolants based on 3-D Gaussian, and use a physically based finite element method and a modal analysis. Then, cinematic attributes are visualized in pseudo colors on the reconstructed surface in order to help medical doctors in their interpretation of the data. Using the presented model, we estimate clinically useful quantitative parameters such as regional wall motion and ejection fraction. Experimental results are shown in a time series of X-ray angiographic images. Copyright ©2001 John Wiley & Sons, Ltd. [source]

Right Ventricular Function in Congenital Heart Defects Assessed by Regional Wall Motion

Risk Stratification and Prognosis in Octogenarians Undergoing Stress Echocardiographic Study

ECHOCARDIOGRAPHY, Issue 8 2007
F. A. C. C., Farooq A. Chaudhry M.D.
Background: The prognostic value of stress echocardiography (SE) for the diagnosis and risk stratification of coronary artery disease in octogenarians is not well defined. Methods: Follow-up of 5 years (mean 2.9 ± 1.0 years) for confirmed nonfatal myocardial infarction (n = 17) and cardiac death (n = 37) was obtained in 335 patients, age ,80 years (mean age 84 ± 3 years, 44% male), undergoing SE (33% treadmill, 67% dobutamine). Left ventricular (LV) regional wall motion was assessed by a consensus of two echocardiographers and scored as per standard five-point scale, 16-segment model of wall motion analysis. Ischemic LV wall segment was defined as deterioration in the thickening and excursion during stress (increase in wall-motion score index (WMSI) ,1). Results: By univariate analysis, inducible ischemia (chi-square = 38.4, P < 0.001), left ventricular ejection fraction (chi-square = 41.2, P < 0.001), a history of previous myocardial infarction (chi-square = 22.3, P < 0.01), hypertension (chi-square = 33, P < 0.01), and age (chi-square = 27.7, P < 0.01) were significant predictors of future cardiac events. WMSI, an index of inducible ischemia, provided incremental prognostic information when forced into a multivariable model where clinical and rest echocardiography variables were entered first. WMSI effectively stratified octogenarians into low- and high-risk groups (annualized event rates of 1.2 versus 5.8%/year, P < 0.001). Conclusions: Stress echocardiography yields incremental prognostic information in octogenarians and effectively stratifies them into low- and high-risk groups. Precise therapeutic decision making in very elderly patients should incorporate combined clinical and stress echocardiography data. [source]

Regional Response of Myocardial Acceleration During Isovolumic Contraction During Dobutamine Stress Echocardiography: A Color Tissue Doppler Study and Comparison with Angiocardiographic Findings

ECHOCARDIOGRAPHY, Issue 10 2005
Linda B. Pauliks M.D.
Background: Color tissue Doppler imaging permits noninvasive quantitation of regional wall motion. In experimental studies, a new marker, the slope of the isovolumic contraction wave, isovolumic acceleration (IVA) was more insensitive to ventricular loading conditions than myocardial velocities. This study compared the regional response IVA to dobutamine stress echocardiography to angiographic findings. Methods: The Myocardial Doppler in Stress Echocardiography (MYDISE) study prospectively recruited 149 consecutive patients with chest pain for dobutamine stress tissue Doppler echocardiography prior to coronary angiography. This color tissue Doppler database was analyzed for IVA in 1192 basal and mid segments at rest and again at peak stress. Angiographic findings were compared to IVA and peak systolic velocities (PSV) in corresponding cardiac segments. The diagnostic accuracy of IVA to predict coronary artery stenosis was determined using cut-off values for three representative segments and with the MYDISE diagnostic model including eight segments. Results: Regional IVA increased in a dose-dependent manner during dobutamine infusion. The response was blunted in the supply territory of stenosed coronary artery branches. IVA performed slightly better than PSV as single marker for coronary artery stenosis. A diagnostic model incorporating IVA and PSV was 85,95% accurate (area under receiver operating characterstic curves). Conclusions: Regional changes of isovolumic acceleration during dobutamine stress echocardiography reflect regional wall motion and can be used to predict coronary artery stenosis with similar accuracy as a model based on systolic myocardial velocities. As a single marker, IVA performed better than myocardial velocities. (ECHOCARDIOGRAPHY, Volume 22, November 2005) [source]

Segmental Differences of Impaired Diastolic Relaxation Following Cardiopulmonary Bypass Surgery in Children: A Tissue Doppler Study

ARTIFICIAL ORGANS, Issue 11 2009
Linda B. Pauliks
Abstract Impaired myocardial relaxation is an important aftereffect of cardiopulmonary bypass (CPB). Infants with their immature calcium metabolism may be particularly vulnerable. However, it has been difficult to quantitate diastolic dysfunction clinically. This study used tissue Doppler to measure regional diastolic myocardial velocities in 31 pediatric patients undergoing open heart surgery. Color tissue Doppler images were acquired in the operating room before and 8 and 24 h post CPB surgery. Early (E) and atrial (A) diastolic velocities were determined. Long axis motion was assessed from apical views near the mitral and tricuspid rings and radial wall motion from the parasternal view. The study included 31 children aged 3.6 ± 4.4 years (6 days to 16 years), with a mean weight of 14.7 ± 13.7 kg and body surface area of 0.59 ± 0.35 m2. Tissue Doppler analysis of regional wall motion revealed abnormal left ventricle (LV) and right ventricle (RV) diastolic relaxation in the early postoperative phase after CPB. Initially, all segments were significantly altered, but by 24 h, regional differences became apparent: LV radial wall motion was recovered, while longitudinal fibers in LV and RV appeared to be less resilient. RV myocardial mechanics were most abnormal. Tissue Doppler analysis may deepen our understanding of myocardial recovery and offers a sensitive tool to compare different cardioprotective strategies. [source]

Postoperative troponin I values: Insult or injury?

CLINICAL CARDIOLOGY, Issue 10 2000
Keith A. Horvath M.D.
Abstract Background: Troponin I (TnI) is increasingly employed as a highly specific marker of acute myocardial ischemia. The value of this marker after cardiac surgery is unclear. Hypothesis: The purpose of this study was to measure serum TnI levels prospectively at 1, 6, and 72 h after elective cardiac operations. In addition, TnI levels were measured from the shed mediastinal blood at 1 and 6 h postoperatively. Serum values were correlated with cross clamp time, type of operation, incidence of perioperative myocardial infarction, as assessed by postoperative electrocardiograms (ECG) and regional wall motion, as documented by intraoperative transesophageal echocardiography (TEE). Methods: Sixty patients underwent the following types of surgery: coronary artery bypass graft (CABG) (n = 45), valve repair/replacement (n = 10), and combination valve and coronary surgery (n = 5). Myocardial protection consisted of moderate systemic hypothermia (30,32°C), cold blood cardioplegia, and topical cooling for all patients. Results: Of 60 patients, 57 (95%) had elevated TnI levels, consistent with myocardial injury, 1 h postoperatively. This incidence increased to 98% (59/60) at 6 h postoperatively. There was a positive correlation between the length of cross clamp time and initial postoperative serum TnI (r = 0.70). There was no difference in the serum TnI values whether or not surgery was for ischemic heart disease (CABG or CABG + valve versus valve). There were no postoperative myocardial infarctions as assessed by serial ECGs. There was no evidence of diminished regional wall motion by TEE. Levels of TnI in the mediastinal shed blood were greater than assay in 58% (35/60) of the patients at 1 h and in 88% (53/60) at 6 h postoperatively. Patients who received an auto-transfusion of mediastinal shed blood (n = 22) had on average a 10-fold postoperative increase in serum TnI levels between 1 and 6 h. Patients who did not receive autotransfusion average less than doubled their TnI levels over the same interval. At 72 h, TnI levels were below the initial postoperative levels but still indicative of myocardial injury. Conclusion: Postoperative TnI levels are elevated after all types of cardiac surgery. There is a strong correlation between intraoperative ischemic time and postoperative TnI level. Further elevation of TnI is significantly enhanced by reinfusion of mediastinal shed blood. Despite these postoperative increases in TnI, there was no evidence of myocardial infarction by ECG or TEE. The postoperative TnI value is even less meaningful after autotransfusion of shed mediastinal blood. [source]

Validation of a new automated method for analysis of gated-SPECT images

CLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 3 2006
Milan Lomsky
Summary We recently presented a new method for quantification of CArdiac FUnction , denoted CAFU , as the first step in the development of an automated method for integrated interpretation of gated myocardial perfusion single photon emission computed tomography (SPECT) images. The aim of this study was to validate CAFU in the assessment of global and regional function of the left ventricle. Quantitative gated-SPECT (QGS), the most widely used software package for quantification of gated-SPECT images, was used as reference method for the measurements of ejection fraction (EF) and ventricular volumes, and visual analysis by an experienced physician was used as reference method for the measurements of regional wall motion and thickening. Two different groups of consecutive patients referred for myocardial perfusion scintigraphy were studied. Global function was evaluated in 316 patients and regional function in 49 other patients. The studies were performed using a 2-day stress/rest 99 m-Tc-sestamibi protocol. A good correlation was found between EF values from QGS and CAFU (EF CAFU = 0·84 EF QGS + 13, r = 0·94), but CAFU values were on average 4 EF points higher than QGS values. With CAFU the segments with normal thickening according to the physician showed significantly higher thickening values (in all parts of the myocardium) compared to the segments classified as having abnormal thickening. In conclusion, this study demonstrates that CAFU can be used to quantify global and regional function in gated-SPECT images. This is an important step in our development of an automated method for integrated interpretation of gated-SPECT myocardial perfusion scintigraphy studies. [source]