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Plane Displacement (plane + displacement)

Distribution by Scientific Domains
Medical Sciences80%

Kinds of Plane Displacement

  • atrioventricular plane displacement
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    Selected Abstracts

    Assessment of Acute Right Ventricular Dysfunction Induced by Right Coronary Artery Occlusion Using Echocardiographic Atrioventricular Plane Displacement

    ECHOCARDIOGRAPHY, Issue 6 2000
    Alpesh R. Shah M.D.
    Right ventricular (RV) systolic function analysis by echocardiography has traditionally required RV endocardial border definition with subsequent tracing and is often inaccurate or impossible in technically poor studies. The atrioventricular plane displacement (AVPD) method attempts to use the descent of the tricuspid annular ring, a reflection of the longitudinal shortening of the right ventricle, as a surrogate marker for RV systolic function. We hypothesized that RV ischemia induced during right coronary artery occlusion proximal to the major right ventricular branches would result in severe right ventricular systolic dysfunction detectable by the AVPD method. During this pilot study, seven patients undergoing elective proximal RCA angioplasty had echocardiographic measurement of RV AVPD performed at baseline (i.e., immediately prior to RCA balloon inflation), during the last 30 seconds of first RCA balloon inflation, and at 1 minute after balloon deflation (recovery). Lateral and medial RV AVPD were significantly reduced from baseline values during intracoronary balloon inflation. (Lateral: 2.45 cm ± 0.22 vs 1.77 cm ± 0.13, P < 0.001; medial: 1.46 cm ± 0.37 vs 1.28 cm ± 0.32, P < 0.05). Additionally, lateral and medial RV AVPD significantly returned towards baseline values during recovery. (Lateral: 2.39 cm ± 0.20, P < 0.001; medial: 1.58 cm ± 0.27, P = 0.01). At baseline, all lateral RV AVPD values were > 2.0 cm, whereas during balloon inflation all were < 2.0 cm. No such clear distinction was found in medial RV AVPD values. Proximal RCA angioplasty is associated with a significant reduction in lateral and medial RV AVPD. Thus RV AVPD may serve as a marker for RV systolic dysfunction. [source]

    Left atrioventricular plane displacement determined by echocardiography: a clinically useful, independent predictor of mortality in patients with stable coronary artery disease

    JOURNAL OF INTERNAL MEDICINE, Issue 5 2003
    E. Rydberg
    Abstract. Rydberg E, Erhardt L, Brand B, Willenheimer R (Malmö University Hospital, University of Lund, Malmö, Sweden). Left atrioventricular plane displacement determined by echocardiography: a clinically useful, independent predictor of mortality in patients with stable coronary artery disease. J Intern Med 2003; 254: 479,485. Background. Echocardiographically determined left atrioventricular plane displacement (AVPD) is strongly related to prognosis in patients with chronic heart failure and in postmyocardial infarction patients. We aimed at exploring whether AVPD, unlike ejection fraction, is related to mortality in patients with stable coronary artery disease (CAD). Methods and results. Atrioventricular plane displacement was assessed by two dimensionally guided M-mode echocardiography in the four and two chamber views, in 333 consecutive patients with stable CAD and an abnormal coronary angiogram. Patients were followed up for an average of 41 months. AVPD was lower in patients who died (n = 30, 9.0 %) compared with survivors (9.0 ± 2.2 vs. 11.5 ± 2.1 mm, P < 0.0001). Amongst patients with prior myocardial infarction (n = 184) AVPD was 8.7 ± 2.3 mm in those who died (n = 17) and 11.2 ± 2.3 mm in the survivors (P < 0.0001). In patients without prior myocardial infarction (n = 149), AVPD was 9.4 ± 2.1 (n = 13) and 11.8 ± 1.8 mm, respectively (P < 0.0001). Age, AVPD and four other echocardiographical variables correlated significantly with prognosis in univariate logistic regression analysis. In multiple logistic regression analysis only AVPD (P < 0.0001) correlated independently with mortality. Conclusion. Echocardiographically determined AVPDis a clinically useful, independent prognostic tool in patients with stable CAD. The presence of a documented previous myocardial infarction does not influence this observation. [source]

    Time-resolved resonance Raman study on ultrafast structural relaxation and vibrational cooling of photodissociated carbonmonoxy myoglobin

    BIOPOLYMERS, Issue 4-5 2002
    Teizo Kitagawa
    Abstract A localized small structural change is converted to a higher order conformational change of protein and extends to a mesoscopic scale to induce a physiological function. To understand such features of protein, ultrafast dynamics of myoglobin (Mb) following photolysis of carbon monoxide were investigated. Recent results are summarized here with a stress on structural and vibrational energy relaxation. The core expansion of heme takes place within 2 ps but the out of plane displacement of the heme iron and the accompanying protein conformational change occur in 10 and 100 s of the picosecond regimes, respectively. Unexpectedly, it was found from UV resonance Raman spectra that Trp7 in the N-terminal region and Tyr151 in the C-terminal region undergo appreciable structural changes upon ligand binding,dissociation while Tyr104, Tyr146, and Trp14 do not. Because of the communication between the movements of these surface residues and the heme iron, the rate of spectral change of the iron-histidine (Fe- His) stretching band after CO photodissociation is influenced by the viscosity of solvent. Temporal changes of the anti-Stokes Raman intensity demonstrated immediate generation of vibrationally excited heme upon photodissociation and its decay with a time constant of 1,2 ps. © 2002 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy) 67: 207,213, 2002 [source]

    Cardiac dysfunction during exercise in patients with primary hyperparathyroidism

    BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 9 2000
    I.-L. Nilsson
    Background ,Non-traditional' manifestations of primary hyperparathyroidism (HPT) are controversial, and include morbidity, mortality and risk factors for cardiovascular diseases with some prospects of normalization by parathyroidectomy (PTX). This study evaluated previously unexplored data on cardiac function during exercise in HPT. Methods Thirty patients with HPT (mean(s.d.) serum calcium 2·96(0·24) mmol l,1) and 30 normocalcaemic controls (selected randomly from the background population, and matched for age and sex) underwent exercise testing, echocardiography and 24-h ambulatory blood pressure recordings before and a mean of 13 months after PTX. Results HPT was associated with higher systolic blood pressure during exercise (mean(s.d.) 223(28) versus 203(33) mmHg; P = 0·02), which correlated to the left ventricular (LV) mass and serum PTH (P = 0·014, P = 0·004); higher LV mass in men (mean(s.d.) 142(20) versus 113(28) g m,2), which might relate to the hypertrophic effect of PTH; and increased LV isovolumic relaxation times (mean(s.d.) 102(19) versus 91(15) ms; P = 0·018), indicating LV diastolic dysfunction. ST depression during exercise decreased significantly (mean(s.d.) , 1·0(0·9) versus 0·7(0·5) mm; P = 0·028) and LV mass declined in proportion with the time after PTX (P = 0·04 in men). PTX also affected systolic functions, as fractional shortening, atrioventricular plane displacement and systolic index decreased in men (P = 0·05, P = 0·04, P = 0·04). Twenty-four-hour blood pressures were higher in HPT (P = 0·008), when subjects on ,-blockers (seven patients, five controls) were excluded, and were unaltered by PTX. Conclusion LV systolic and diastolic dysfunction occurs in HPT. The diastolic dysfunction seems to diminish with time after PTX, while the positive inotropic effect of calcium in itself may alleviate the systolic dysfunction. © 2000 British Journal of Surgery Society Ltd [source]