28 research outputs found
Quantification of resting myocardial blood flow velocity in normal humans using real-time contrast echocardiography. A feasibility study
BACKGROUND: Real-time myocardial contrast echocardiography (MCE) is a novel method for assessing myocardial perfusion. The aim of this study was to evaluate the feasibility of a very low-power real-time MCE for quantification of regional resting myocardial blood flow (MBF) velocity in normal human myocardium. METHODS: Twenty study subjects with normal left ventricular (LV) wall motion and normal coronary arteries, underwent low-power real-time MCE based on color-coded pulse inversion Doppler. Standard apical LV views were acquired during constant IV. infusion of SonoVue(®). Following transient microbubble destruction, the contrast replenishment rate (β), reflecting MBF velocity, was derived by plotting signal intensity vs. time and fitting data to the exponential function; y (t) =A (1-e(-β(t-t0))) + C. RESULTS: Quantification was feasible in 82%, 49% and 63% of four-chamber, two-chamber and apical long-axis view segments, respectively. The LAD (left anterior descending artery) and RCA (right coronary artery) territories could potentially be evaluated in most, but contrast detection in the LCx (left circumflex artery) bed was poor. Depending on localisation and which frames to be analysed, mean values of [Image: see text] were 0.21–0.69 s(-1), with higher values in medial than lateral, and in basal compared to apical regions of scan plane (p = 0.03 and p < 0.01). Higher β-values were obtained from end-diastole than end-systole (p < 0.001), values from all-frames analysis lying between. CONCLUSION: Low-power real-time MCE did have the potential to give contrast enhancement for quantification of resting regional MBF velocity. However, the technique is difficult and subjected to several limitations. Significant variability in β suggests that this parameter is best suited for with-in patient changes, comparing values of stress studies to baseline
Incremental value of strain rate imaging to wall motion analysis for prediction of outcome in patients undergoing dobutamine stress echocardiography
Background - Wall motion score at dobutamine stress echocardiography is an independent predictor of mortality. We sought to determine whether quantification of DSE by strain rate imaging was incremental to wall motion score for predicting outcome. Methods and Results - In 646 patients undergoing dobutamine stress echocardiography for the evaluation of known or suspected coronary disease, customized software was used to automatically measure peak systolic strain rate (SRs) and end-systolic strain (Se-s) in 18 segments. Results were expressed as the number of abnormal segments and the mean SRs and S-es per patient. All-cause mortality was identified over 7 years of follow-up (mean, 5.2 +/- 1.5 years). Contributions of clinical, wall motion, and SRs and S-es data to outcome were analyzed with Cox models, which also were used to define cut points for SRs and S-es. Ischemia (new or worsening wall motion abnormalities) was detected in 45%, and 39% had a previous myocardial infarction. In patients with no ischemia, annualized mortality without and with previous myocardial infarction were 2% and 3% compared with 5% in patients with ischemia. Peak wall motion score index, mean SRs, segmental S-es, and segmental SRs were all predictors of mortality, but only segmental SRs (hazard ratio, 3.6; 95% CI, 1.7 to 7.2) was independently predictive. In sequential Cox models, the model based on clinical data (overall chi(2), 12.7) was improved by peak wall motion score index (18.4, P = 0.002) and further increased by either segmental SRs (31.8, P < 0.001) or mean SRs (25.7, P = 0.009). Conclusions - Segmental analysis by SRs, derived from automated strain rate imaging analysis of dobutamine stress echocardiography response, offers prognostic information that is independent and incremental to standard wall motion score index
Impact of age and haemodynamics on strain rate during dobutamine stress echocardiography: is designation of a normal range feasible?
The MacNew Heart Disease Health-Related Quality of Life Questionnaire: A Scandinavian Validation Study
The aim of this study is to validate the Danish, Norwegian and Swedish versions of the self-administered MacNew Heart Disease Health-related Quality of Life questionnaire in patients with ischemic heart disease. The MacNew questionnaire, the Short Form SF-36, and the Hospital Anxiety and Depression Scale were completed at baseline by 976 patients (Denmark n = 353, Norway n = 328, Sweden n = 295) with a diagnosis of angina (n = 335), myocardial infarction (n = 352), or heart failure (n = 289). Each language version of the MacNew satisfied reliability criteria with Cronbach’s α values for the total group data (0.90–0.94) as well as the diagnostic group data (0.91–0.96). The test–retest correlations exceeded the criteria for group comparison (r ≥ 0.70) in Danish and Norwegian patients. The multidimensionality of the MacNew was confirmed although the original three-factor solution did not fully meet the criteria for good fit. Convergent and discriminative validity were confirmed in each language and diagnosis group with the exception of discriminative validity in Swedish angina patients. The psychometric properties of the Danish, Norwegian, and Swedish versions of the MacNew are largely confirmed. The MacNew can be recommended as a specific instrument for assessing and evaluating HRQL in Danish, Norwegian, and Swedish patients with angina, MI, and heart failure. However, the MacNew factor structure needs to be revisited in future studies