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In the present study, the relation between improvement in the left ventricular ejection fraction (LVEF) and heart failure symptoms was evaluated in 100 patients with ischemic cardiomyopathy undergoing coronary revascularization. In patients with viable myocardium, the improvement in the LVEF after revascularization was accompanied by improvement in heart failure symptoms in most patients (80%); most viable patients (75%) without improvement in LVEF also showed an improvement in New York Heart Association functional class. Conversely, most nonviable patients failed to improve in LVEF or New York Heart Association class.

Background: Patients with severe left ventricular dysfunction and myocardial viability by dobutamine stress echocardiography (DSE) or F18-fluorodeoxyglucose-single-photon emission computed tomography (FDG-SPECT), experience improved survival after coronary revascularization. Pulsed wave-tissue Doppler imaging (PW-TDI)-derived ejection phase shortening (EPS) and post-systolic shortening (PSS) velocities may help to quantify DSE. We assessed these variables in a prospective long-term follow-up., Methods: Eighty patients (58 men, mean age 63+/-9 years) with left ventricular dysfunction (radionuclide ventriculography mean ejection fraction, 34+/-11%) underwent both DSE and FDG-SPECT for myocardial viability. Viable myocardium was improvement from rest to low dose or worsening of wall motion at peak DSE and normal perfusion, mildly reduced perfusion with FDG uptake or severely reduced or absent perfusion with increased FDG uptake (mismatch) at FDG-SPECT. EPS, PSS velocities and EPS/PSS ratio during DSE were analysed using a six-segment model. Coronary revascularization bypass grafting was performed in 62 patients. All patients completed a long-term (9-year) follow-up for cardiac death., Results: The segmental prevalence of severe dyssynergy was 77%. On a patient basis myocardial viability was detected by EPS/PSS ratio (31%), FDG-SPECT (34%) and DSE (26%). A significant improvement of Kaplan-Meier survival was predicted in viable compared with nonviable revascularized patients (P < 0.01). Both EPS/PSS ratio and FDG-SPECT, compared to DSE alone, tended to allocate more accurately univariate prediction of death-free outcome (odds ratio, 2.5 and 2.7 compared with 2.1)., Conclusions: TDI adds objective variables to DSE, helping to recognize viable myocardium and optimize prediction of death-free outcome in long-term follow-up, with favorable comparison with nuclear techniques.

Objective: To evaluate the potential of a simple and widely available technique as two-dimensional (2D) echocardiography to identify patients with ischemic cardiomyopathy and low likelihood of functional recovery after coronary revascularization., Methods: Two-dimensional echocardiography and radionuclide ventriculography (RNV) were performed before coronary revascularization in 94 patients with ischemic cardiomyopathy. Left ventricular ejection fraction (LVEF) was measured by RNV. Regional wall motion abnormalities, wall motion score index, end-diastolic wall thickness (EDWT), left ventricular (LV) volumes and LV sphericity index were assessed in the echocardiographic images. RNV was repeated 9-12 months after revascularization to assess LVEF change; an improvement >or=5% was considered clinically significant., Results: Nine hundred and ninety-nine segments were severely dysfunctional; 149 out of 999 (15%) had an EDWT or=100 ml/ml) and of the end-systolic volume index (>or=80 ml) was present in 32 (34%) and 21 (22%) patients, respectively. A spherical shape of the LV was observed in 35 (37%) patients. LVEF after revascularization increased in 30 out of 94 patients (32%) from 30+/-8% to 39+/-9% (P<0.0001). On multivariate analysis, the EDVI was the only predictor of no recovery in LVEF [odds ratio, 1.06, confidence interval (CI), 1.04-1.1, P<0.0001]. The cut-off value of EDVI >or=90 ml/ml accurately identified patients that virtually never recover. Post-operatively, LVEF increased in three out of 42 (7%, 95% CI 0-15%) patients with EDVI >or=90 ml/ml as compared to 27 out of 52 (52%) patients with EDVI<90 ml/ml (P<0.0001)., Conclusions: In patients with ischemic cardiomyopathy and severe LV enlargement, improvement of LVEF after revascularization is unlikely to occur. Conversely, in patients with relatively preserved LV size, a higher likelihood of functional recovery may be anticipated.

Background: QT dispersion is prolonged in numerous cardiac diseases, representing a general repolarization abnormality., Aim: To evaluate the influence of viable myocardium on QT dispersion in patients with severely depressed left ventricular (LV) function due to coronary artery disease., Methods and Results: 103 patients with ischemic cardiomyopathy (LV ejection fraction [EF]: 25+/-6%) were studied. Patients underwent 12-lead electrocardiography to assess QT dispersion, and two-dimensional echocardiography to identify segmental dysfunction. Dobutamine stress echocardiography (DSE) was then performed to detect residual viability. Resting echo demonstrated 1260 dysfunctional segments; of these, 476 (38%) were viable. Substantial viability (> or =4 viable segments on DSE) was found in 62 (60%) patients. QT dispersion was lower in these patients, than in patients without viability (55+/-17 ms vs. 65+/-22 ms, P=0.012). Viable segments negatively correlated to QT dispersion (r=-0.333, P=0.001). In contrast, there was no correlation between LVEF and QT dispersion (r=-0.001, P=NS)., Conclusions: There is a negative correlation between QT dispersion and the number of viable segments assessed by DSE. Patients with severely depressed LV function and a low QT dispersion probably have a substantial amount of viable tissue. Conversely, when QT dispersion is high, the likelihood of substantial viability is reduced.

Objective: In patients with ischemic cardiomyopathy and a substantial amount of dysfunctional but viable myocardium, myocardial revascularization may improve left ventricular ejection fraction. The aim of this study was to evaluate why not all patients with a substantial amount of viable tissue recover in function after revascularization., Methods: A total of 118 consecutive patients with a depressed left ventricular ejection fraction (on average 29% +/- 6%) due to chronic coronary artery disease underwent myocardial revascularization. Before revascularization all patients underwent dobutamine stress echocardiography to assess regional dysfunction, left ventricular volumes, and myocardial viability as well as radionuclide ventriculography to determine the left ventricular ejection fraction. Next, 3 to 6 months after revascularization, the left ventricular ejection fraction and regional contractile function were reassessed. Improvement of left ventricular ejection fraction > or = 5% following revascularization was considered clinically significant., Results: Dobutamine stress echocardiography revealed that 489 (37%) of the 1329 dysfunctional segments were viable. A total of 61 (52%) patients had a substantial amount of viable myocardium (> or = 4 viable segments). In these 61 patients the global function was expected to recover > or = 5% after revascularization. However, left ventricular ejection fraction did not improve in 20 (33%) of 61 patients despite the presence of substantial viability. Clinical characteristics and echocardiographic data were comparable between patients with and without improvement. However, patients without improvement had considerably larger end systolic volumes (153 +/- 41 mL vs 133 +/- 46 mL, P =.007). The likelihood of recovery of global function decreased proportionally with the increase of end systolic volume (P <.001, R = 0.43, n = 61). Receiver operating characteristic curve analysis demonstrated that an end systolic volume > or = 140 mL had the highest sensitivity/specificity to predict the absence of global recovery., Conclusions: In patients with ischemic cardiomyopathy not only the amount of dysfunctional but viable myocardium but also the extent of left ventricular remodeling determines the improvement in function following myocardial revascularization. Patients with a high end systolic volume due to left ventricular remodeling have a decreased likelihood of improvement of global function.

The aim of this study was to evaluate the relation between QT dispersion and myocardial viability as assessed by single-photon emission computed tomography. The study population included 97 consecutive patients with severely impaired left ventricular function secondary to chronic coronary artery disease. Patients with a low QT dispersion had a substantial amount of viable myocardium, whereas patients with a high QT dispersion had predominantly nonviable scar tissue.

Currently, the prediction of improvement of left ventricular (LV) ejection fraction (EF) after revascularization in patients with ischemic cardiomyopathy relies only on viable myocardium extent, whereas both the amount of viable and scar tissue may be important. A model was developed, based on the amount of viable and nonviable myocardium, to predict functional recovery. Viable and scarred myocardium was defined by dobutamine stress echocardiography (DSE) in 108 consecutive patients. LVEF before and 9 to 12 months after revascularization was assessed by radionuclide ventriculography; an improvement of > or =5% was considered significant. In the 1,089 dysfunctional segments (63%), DSE elicited biphasic response in 216 segments (20%), sustained improvement in 205 (19%), worsening in 43 (4%), and no change in 625 (57%). LVEF improved in 39 patients (36%). Only the numbers of biphasic and scar segments were predictors of improvement or no improvement of LVEF (odds ratio 1.5, 95% confidence interval 1.2 to 1.7, p <0.0001 for biphasic segments; odds ratio 0.8, 95% confidence interval 0.7 to 0.9, p <0.0005 for scarred segments). The sustained improvement and worsening pattern were not predictive of improvement or no improvement. A regression function, based on the number of scar and biphasic segments, showed that the likelihood of recovery was 85% in patients with extensive biphasic tissue and no scars and 11% in patients with extensive scars and no biphasic myocardium. Patients with a mixture of scar and biphasic tissue had an intermediate likelihood of improvement (50%). In patients with ischemic cardiomyopathy and a mixture of viable and nonviable tissue, both numbers of viable and nonviable segments should be considered to accurately predict functional recovery after revascularization.

Background: Repeat coronary artery bypass grafting (redo-CABG) in patients with ischaemic cardiomyopathy is associated with high perioperative risk and worse long-term outcome compared with patients undergoing their first CABG. Objective: To assess whether patients with viable myocardium undergoing redo-CABG have a better outcome. Methods: 18 patients with ischaemic cardiomyopathy underwent redo-CABG and 34 underwent their first CABG; all had substantial viability (⩾25% of the left ventricle) on dobutamine stress echocardiography (DSE). Left ventricular ejection fraction (LVEF) and heart failure symptoms were assessed before and 9–12 months after revascularisation. Cardiac event rate was assessed during the follow-up period (median 4 years, 25–75th centile 2.8–4.9 years). Results: The extent of viable myocardium on DSE was comparable in the two groups (11.3 (3.9) segments in patients who underwent redo-CABG v 12.8 (3.0) in patients who underwent their first CABG; p = NS). LVEF improved from 32% (9%) to 39% (12%); p=0.01, in patients who underwent redo-CABG and from 30% (7%) to 36% (7%); p<0.01, in those who underwent their first CABG; New York Heart Association class improved from 2.5 (1.1) to 1.9 (0.8); p=0.03, and from 2.7 (1.0) to 1.8 (0.70); p<0.01, respectively. In patients who underwent redo-CABG, the perioperative mortality was 0, post-surgery inotropic support was needed in 11% of the patients and mid-term (4-year) survival was 100%, with a total event rate of 28%. All these variables were not statistically different from patients who underwent their first CABG (p = 0.50, 0.90, 0.08 and 0.81, respectively). Conclusion: Patients with ischaemic cardiomyopathy and substantial viability undergoing redo-CABG benefit from revascularisation in terms of improvement in LVEF, heart failure symptoms, angina and mid-term prognosis. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the relative merits of viability and ischaemia for prognosis after revascularisation. Methods: Low-high dose dobutamine stress echocardiography (DSE) was performed before revascularisation in 128 consecutive patients with ischaemic cardiomyopathy (mean (SD) left ventricular ejection fraction (LVEF) 31 (8)%). Viability (defined as contractile reserve (CR)) and ischaemia were assessed during low and high dose dobutamine infusion, respectively. Cardiac death was evaluated during a five year follow up. Clinical, angiographic, and echocardiographic data were analysed to identify predictors of events. Results: Univariable predictors of cardiac death were the presence of multivessel disease (hazard ratio (HR) 0.21, p < 0.001), baseline LVEF (HR 0.90, p < 0.0001), wall motion score index (WMSI) at rest (HR 4.02, p = 0.0006), low dose DSE (HR 7.01, p < 0.0001), peak dose DSE (HR 4.62, p < 0.0001 ), the extent of scar (HR 1.39, p < 0.0001 ), and the presence of CR in ⩾ 25% of dysfunctional segments (HR 0.34, p = 0.02). The best multivariable model to predict cardiac death included the presence of multivessel disease, WMSI at low dose DSE, and the presence of CR in ⩾ 25% of the severely dysfunctional segments (HR 9.62, p < 0.0001). Inclusion of ischaemia in the model did not provide additional predictive value. Conclusion: The findings of the present study illustrate that in patients with ischaemic cardiomyopathy, the extent of viability (CR) is a strong predictor of long term prognosis after revascularisation. Ischaemia did not add significantly in predicting outcome. [ABSTRACT FROM AUTHOR]

Objectives: To assess whether quantification of myocardial systolic velocities by pulsed wave tissue Doppler imaging can differentiate between stunned, hibernating, and scarred myocardium.Design: Observational study.Setting: Tertiary referral centre.Patients: 70 patients with reduced left ventricular function caused by chronic coronary artery disease.Methods: Pulsed wave tissue Doppler imaging was done close to the mitral annulus at rest and during low dose dobutamine; systolic ejection velocity (Vs) and the difference in Vs between low dose dobutamine and the resting value (DeltaVs) were assessed using a six segment model. Assessment of perfusion (with Tc-99m-tetrofosmin SPECT) and glucose utilisation (by 18F-fluorodeoxyglucose SPECT) was used to classify dysfunctional regions (by resting cross sectional echocardiography) as stunned, hibernating, or scarred.Results: 253 of 420 regions (60%) were dysfunctional. Of these, 132 (52%) were classified as stunned, 25 (10%) as hibernating, and 96 (38%) as scarred. At rest, Vs in stunned, hibernating, and scar tissue was, respectively, 6.3 (1.8), 6.6 (2.2), and 5.5 (1.5) cm/s (p = 0.001 by ANOVA). There was a gradual decline in Vs during low dose dobutamine infusion between stunned, hibernating, and scar tissue (8.3 (2.6) v 7.8 (1.5) v 6.8 (1.9) cm/s, p < 0.001 by ANOVA). DeltaVs was higher in stunned (2.1 (1.9) cm/s) than in hibernating (1.2 (1.4) cm/s, p < 0.05) or scarred regions (1.3 (1.2) cm/s, p = 0.001).Conclusions: Quantitative tissue Doppler imaging showed a gradual reduction in regional velocities between stunned, hibernating, and scarred myocardium. Dobutamine induced contractile reserve was higher in stunned regions than in hibernating and scarred myocardium, reflecting different severities of myocardial damage. [ABSTRACT FROM AUTHOR]

Background: In patients with ischaemic cardiomyopathy and viable myocardium, left ventricular ejection fraction (LVEF) does not always improve after revascularisation. Whether this may affect prognosis is unclear. Objective: To evaluate the prognosis of viable patients with and without improvement of LVEF after coronary revascularisation. Methods: Before revascularisation, radionuclide ventriculography (RNV) and dobutamine stress echocardiography were performed to assess LVEF and myocardial viability, respectively. Nine to 12 months after revascularisation, LVEF improvement was assessed by RNV. Patients were divided into three groups: group 1, viable patients with LVEF improvement (n = 27); group 2, viable patients without LVEF improvement (n = 15), group 3, non-viable patients (n = 48). Cardiac events were evaluated during a 4-year follow-up. Results: After revascularisation, the mean (SD) LVEF improved from 32 (9)% to 42 (10)% in group 1, but did not change significantly in group 2 and in group 3, p<0.001 by analysis of variance (ANOVA). Heart failure symptoms improved in both groups 1 (mean (SD) NYHA class from 3.1 (0.9) to 1.7 (0.7)) and 2 (from 3.2 (0.7) to 1.7 (0.9)), but not in group 3 (from 2.8 (1.0) to 2.7 (0.5)), p<0.001 by ANOVA. During follow-up, the cardiac event rate was low (4%) in group 1, intermediate (21%) in group 2 and high (33%) in group 3 (p = 0.01). Conclusion: The best prognosis after revascularisation may be expected in those viable patients whose LVEF improves. Conversely, viable patients without functional improvement have an intermediate prognosis. [ABSTRACT FROM AUTHOR]

An abstract of the article "QT Dispersion Correlates to Myocardial Viability Assessed by Dobutamine Stress Echocardiography in Patients With Ischemic Cardiomyopathy" by M. Bountioukos and colleagues is presented.

An abstract of the article "Can resting 2D echocardiography identify patients with ischemic cardiomyopathy and low likelihood of functional improvement after revascularization?" by V. Rizzello and colleagues is presented.

An abstract of the article "Beneficial Effects of Coronary Revascularization on Left Ventricular Remodelling in Patients With Ischemic Cardiomyopathy: The Role of Viable Myocardium" by V. Rizzello and colleagues is presented.

An abstract of the article "Quantification of regional left ventricular function in Q-wave and non-Q-wave dysfunctional regions by tissue Doppler imaging in patients with ischaemic cardiomyopathy" by M. Bountioukos and colleagues is presented.