Usefulness of exercise-stress echocardiography for risk stratification of true asymptomatic patients with aortic valve stenosis.

Aims Abnormal exercise test defined as the occurrence of exercise limiting symptoms, fall in blood pressure below baseline, or complex ventricular arrhythmias is useful to predict clinical events in asymptomatic patients with aortic stenosis (AS). The purpose of this study was to determine whether exercise-stress echocardiography (ESE) adds any incremental prognostic value to resting echocardiography in patients with AS having a normal exercise response. Methods and results One hundred and eighty-six asymptomatic patients with at least moderate AS and preserved LV ejection fraction (>/=50%) were assessed by Doppler-echocardiography at rest and during a maximum ramp semi-supine bicycle exercise test. Fifty-one (27%) patients had an abnormal exercise test and were excluded from the present analysis. Among the 135 patients with normal exercise test, 67 had an event (aortic valve replacement motivated by symptoms or cardiovascular death) at a mean follow-up of 20 +/- 14 months. The variables independently associated with events were: age >/=65 years [hazard ratio (HR) = 1.96; 95% confidence interval (CI): 1.15-3.47; P = 0.01], diabetes, (HR = 3.20; 95% CI: 1.33-6.87; P = 0.01), LV hypertrophy (HR = 1.96; 95% CI: 1.17-3.27; P = 0.01), resting mean gradient >35 mmHg (HR = 3.60; 95% CI: 2.11-6.37; P < 0.0001), and exercise-induced increase in mean gradient >20 mmHg (HR = 3.83; 95% CI: 2.16-6.67; P < 0.0001). Conclusion The exercise-induced increase in transvalvular gradient may be helpful to improve risk stratification in asymptomatic AS patients with normal exercise response. These results thus suggest that ESE may provide additional prognostic information over that obtained from standard exercise testing and resting echocardiography.

Pivotal role of bedside Doppler echocardiography in the assessment of patients with acute heart failure and mitral regurgitation.

Patients presenting with mitral regurgitation and acute heart failure remain a challenge for the clinicians. Bedside echocardiography ascertains the functional or primary nature of mitral regurgitation, thereby allowing to focus therapy on the left ventricle and mitral valve apparatus in patients with functional mitral regurgitation and to hasten mitral valve repair or replacement when acute heart failure results from primary mitral regurgitation. This short article reviews the evaluation by bedside echocardiography to guide management of these patients.

Stress echocardiography to assess stenosis severity and predict outcome in patients with paradoxical low-flow, low-gradient aortic stenosis and preserved LVEF.

The objective of this study was to examine the value of stress-echocardiography in patients with paradoxical low-flow, low-gradient (PLFLG) aortic stenosis (AS). The projected aortic valve area (AVAProj) at a normal flow rate was calculated in 55 patients with PLFLG AS. In the subset of patients (n = 13) who underwent an aortic valve replacement within 3 months after stress echocardiography, AVA(Proj) correlated better with the valve weight compared to traditional resting and stress echocardiographic parameters of AS severity (AVA(Proj): r = -0.78 vs. other parameters: r = 0.46 to 0.56). In the whole group (N = 55), 18 (33%) patients had an AVA(Proj) >1.0 cm(2), being consistent with the presence of pseudo severe AS. The AVA(Proj) was also superior to traditional parameters of stenosis severity for predicting outcomes (hazard ratio: 1.32/0.1 cm(2) decrease in AVA(Proj)). In patients with PLFLG AS, the measurement of AVA(proj) derived from stress echocardiography is helpful to determine the actual severity of the stenosis and predict risk of adverse events.

Clinical value of exercise Doppler echocardiography in patients with cardiac-valvular disease.

Besides its usefulness for the detection of exercise-induced ischemia, conventional exercise testing may help to predict the onset of clinical events and the need for surgery in asymptomatic patients with cardiac-valvular disease. Doppler echocardiography examination during exercise recently emerged as a new stress testing modality that may add useful information regarding dynamism of LV function, valve disease severity and pulmonary circulation. Few studies have demonstrated a correlation between the results of exercise Doppler echocardiography and clinical outcome. Preliminary experience needs to be confirmed to warrant routine use of Doppler echocardiography examination during exercise in the evaluation of patients with cardiac-valve disease.