Increased distance between mitral valve coaptation point and mitral annular plane: significance and correlations in patients with heart failure.

OBJECTIVE: To measure the distance between the mitral leaflet coaptation point and the mitral annulus (CPMA) and assess the relation of this index to structural and functional characteristics of the failing left ventricle. DESIGN: Echocardiographic indices and CPMA were measured at baseline and again during dobutamine infusion and leg lifting. Left ventricular diastolic and systolic dimensions, left ventricular ejection fraction (LVEF) by Simpson's rule, mitral annulus dimension, and E point septal separation were correlated with CPMA. SETTING: Tertiary referral centre. PATIENTS: The total study population of 129 patients included 94 with LVEF < 35% and 35 with LVEF 35%-45%; 76 had coronary artery disease and 53 had dilated cardiomyopathy. INTERVENTIONS: A dobutamine infusion was given in 18 patients and preload increase by leg lifting in 28. MAIN OUTCOME MEASURES: Correlations between CPMA and contractility indices at baseline and during interventions. RESULTS: CPMA was correlated with left ventricular diastolic dimension (r = 0.52), left ventricular systolic dimension (r = 0.53), LVEF (r = -0.44), fractional shortening (r = -0.42), E point septal separation (r = 0.48), and mitral annulus dimension (r = 0.44) (all p < 0.001). Dobutamine decreased CPMA from (mean (SD)) 12.04 (3.64) mm to 8.92 (2.56) mm and increased LVEF from 27 (6.2)% at baseline to 33.4 (6.9)% at 10 microg/kg/min (both p < 0.001). These changes were strongly related (r = 0.68, p < 0.007). After leg lifting, CPMA decreased from 13 (4) mm at baseline to 10 (3) mm (p < 0.001), and LVEF increased from 32 (11)% at baseline to 39 (11)% (p < 0.001). Fractional shortening and left ventricular diastolic dimension also increased (p < 0.001) and mitral annulus dimension and E point septal separation decreased (p < 0.002), but left ventricular systolic dimension did not change. CONCLUSIONS: The mechanism displacing the mitral coaptation point towards the left ventricular apex is multifactorial. The correlations between CPMA difference (before versus after interventions) and ejection fraction difference (before versus after interventions) shows that this index depends mainly on left ventricular function.

Prognostic significance of echocardiographically estimated right ventricular shortening in advanced heart failure.

Little is known about the association of echocardiographic estimates of right ventricular (RV) function with survival, in relation to hemodynamic and exercise-derived predictors of outcome in congestive heart failure. We prospectively studied 40 patients (age 55+/-10 years, in New York Heart Association functional class III [70%] and IV [30%]), with left ventricular (LV) ejection fraction <30%. At enrollment, all patients underwent echocardiographic evaluation of LV dimensions and function. RV shortening was measured as the difference of the end-diastolic distance - the end-systolic distance between the tricuspid annulus and the RV apex. Thirty-five patients (88%) were able to perform a maximal symptom-limited exercise test. Peak oxygen consumption (peak VO2) and percent peak age- and gender-adjusted predicted oxygen consumption (%peak VO2) were calculated. Of 40 patients, 10 died during a mean follow-up period of 14+/-10 months. On univariate analysis, nonsurvivors had lower RV shortening (p=0.0001), higher pulmonary artery wedge pressure (p=0.009), higher pulmonary vascular resistance (p=0.02), and lower mean aortic pressure (p=0.05). Cox proportional-hazards model revealed that the only independent associate of survival was RV shortening (p=0.0005), with a trend toward significance for mean aortic pressure (p=0.08). The best cutoff point of RV shortening identified by the receiver-operating curve was 1.25 cm. This value had a sensitivity of 90%, specificity of 80%, and overall predictive accuracy of 83% to distinguish survivors from nonsurvivors. In patients with advanced heart failure, preserved RV function as indicated by an echocardiographically derived RV shortening > 1.25 cm is a strong predictor of survival.

Influence of mitral regurgitation on left atrial thrombus and spontaneous echocardiographic contrast in patients with rheumatic mitral valve disease.

The aim of this study was to investigate the influence of mitral regurgitation (MR) on left atrial (LA) thrombus formation and spontaneous echocardiographic contrast in patients with rheumatic mitral valve disease. LA thrombus and spontaneous contrast are considered risk factors for embolic complications. The presence of MR has been related to a low incidence of embolization; however, its effect on thrombus formation and spontaneous contrast has not been clarified. We studied by transesophageal echocardiography 55 patients with rheumatic mitral valve disease, who were receiving anticoagulant treatment. Atrial thrombus was detected in 13 patients who had a lower incidence of significant MR (p < 0.03), a smaller regurgitant jet (p < 0.02), and a higher incidence of atrial fibrillation (p < 0.05) than the rest of the group. Spontaneous contrast was detected in 34 patients with larger atria (p < 0.006), smaller regurgitant jets (p < 0.05), a smaller mitral valve area (p < 0.008), and a higher incidence of atrial fibrillation (p < 0.002) than the rest of the group. Patients without significant MR are at high risk for LA thrombus formation and subsequent embolization and represent a subgroup in whom careful anticoagulation is needed. Conversely, the presence of significant MR correlates with a lower incidence of spontaneous contrast, thrombi, and embolization.