Low-dose dobutamine responsiveness in idiopathic dilated cardiomyopathy: relation to exercise capacity and clinical outcome.

To evaluate myocardial contractile reserve using low-dose dobutamine echocardiography in patients with chronic heart failure secondary to idiopathic dilated cardiomyopathy stratified by peak exercise oxygen consumption (VO(2)). Sixty clinically stable patients (56+/-11 years; 45 males) with idiopathic cardiomyopathy and NYHA class I to III symptoms of heart failure were studied and followed-up for 13+/-3 months. All patients underwent cardiopulmonary exercise testing and low-dose dobutamine. The dobutamine infusion protocol consisted of an initial dose of 2.5 micro. kg(-1)per 3 min, increasing by 2.5 micro. kg(-1)per min every 3 min; the maximal dose was 10 micro. kg(-1)per min. The end-systolic volume index, left ventricular ejection fraction and cardiac output were measured at baseline and peak dobutamine dose and their change calculated as ((peak dose value-baseline value)/baseline value]x100. Ten normal subjects with normal left ventricular function and no coronary artery lesions served as a control group to compare low-dose dobutamine results. All analysed echocardiographic variables either at baseline or following dobutamine infusion were significantly lower in patients with chronic heart failure as a whole compared to the control group. When the patients were grouped according to Weber's classification, a statistically significant decrease in percentange changes in end-systolic volume index (rho=-0.77;P<0.0001), left ventricular ejection fraction (rho=-0.72;P<0.0001) and cardiac output (rho=-0. 82;P<0.0001) from class A to class C was observed. The mean percentage decrease in end-systolic volume index following the dobutamine infusion was 28.7+/-9% in class A (peak VO(2)>20 ml. kg(-1). min(-1)), 18.6+/-8% in class B (peak VO(2)between 16 and 20 ml. kg. min(-1)), and only 6.4+/-6% in class C (peak VO(2)between 10 and 16 ml. kg(-1). min(-1)) patient groups. At multivariate analysis, only the percentage change in end-systolic volume index was significantly associated with a peak VO(2)<15 ml. kg(-1). min(-1)(P=0.006). During the follow-up, 17 patients had events (15 readmissions for worsening heart failure and two deaths). At multivariate analysis, only the percentage change in end-systolic volume index was significantly associated with the occurrence of events (P=0.003). The area under the receiver operating characteristic curve for percentage change in end-systolic volume index was not significantly different from that for peak VO(2)(0. 86+/-0.04 vs 0.80+/-0.06;P:ns). This study indicates that in patients with chronic heart failure secondary to idiopathic cardiomyopathy, the cardiac response to low-dose dobutamine, as assessed by echocardiography, is correlated with peak VO(2), an objective and accurate measure of the severity of the disease and clinical outcome.

Scrutinio D ，Napoli V ，Passantino A ，Ricci A ，Lagioia R ，Rizzon P ... -  《EUROPEAN HEART JOURNAL》

Prognostic value of changes over time in exercise capacity and echocardiographic measurements in patients with chronic heart failure.

This study sought to examine the predictive values of changes over time in exercise capacity and echocardiographic measurements of ventricular dimensions or function in predicting mortality in patients with chronic heart failure. Sixty-two patients with chronic heart failure (58 men, mean [+/-SD] age 60+/-10 years, mean peak oxygen consumption (VO(2)) 18.2+/- 5.9 ml. kg(-1). min(-1), mean left ventricular ejection fraction 38.9+/-15. 8%) who underwent both treadmill exercise testing and echocardiographic examination on two occasions, separated by 19+/-15 months were followed-up for a mean of 17 months (interquartile range 9-30 months). During the follow-up period, 19 patients (30%) died and three (4.8%) underwent heart transplantation. Of measurements taken at a single time-point (visit 2) exercise duration, peak VO(2), ventilatory response to exercise (VE/VCO(2)), left atrial diameter and left ventricular ejection fraction were found, by Cox proportional-hazard analysis, to predict the outcome in these patients (all P<0.05). Of the changes in parameters between visit 1 to visit 2, only changes in peak VO(2)per year (P=0.026) predicted non-transplanted survival (independent of changes in left ventricular ejection fraction and VE/VCO(2)). In Kaplan-Meier survival analysis patients with increased peak VO(2)over time (n=28) showed a better prognosis at 2 years (cumulative survival 75% [95% confidence interval: 56-95%] than those with a decrease in peak VO(2)(n=34, cumulative survival 50% [95% confidence interval: 31-68%]). Although single estimates of peak VO(2), VE/VCO(2)and left ventricular ejection fraction have significant prognostic importance in patients with chronic heart failure, when monitoring changes over time only peak VO(2)remains a significant predictor of outcome.

Florea VG ，Henein MY ，Anker SD ，Francis DP ，Chambers JS ，Ponikowski P ，Coats AJ ... -  《EUROPEAN HEART JOURNAL》

Left ventricular diastolic filling pattern predicts cardiopulmonary determinants of functional capacity in patients with congestive heart failure.

Parthenakis FI ，Kanoupakis EM ，Kochiadakis GE ，Skalidis EI ，Mezilis NE ，Simantirakis EN ，Kanakaraki MK ，Vardas PE ... -  《AMERICAN HEART JOURNAL》

Effects of dobutamine on left ventricular shape and geometry: an easy way to detect the functional status of chronic heart failure in patients with dilated cardiomyopathy.

Paraskevaidis IA ，Dodouras T ，Adamopoulos S ，Kremastinos DT ... -  《JOURNAL OF THE AMERICAN SOCIETY OF ECHOCARDIOGRAPHY》

Association between left atrial myocardial function and exercise capacity in patients with either idiopathic or ischemic dilated cardiomyopathy: a two-dimensional speckle strain study.

D'Andrea A ，Caso P ，Romano S ，Scarafile R ，Cuomo S ，Salerno G ，Riegler L ，Limongelli G ，Di Salvo G ，Romano M ，Liccardo B ，Iengo R ，Ascione L ，Del Viscovo L ，Calabrò P ，Calabrò R ... -  《-》