Coronary sinus dilatation is a sign of impaired right ventricular function in patients with heart failure

OBJECTIVE The coronary sinus (CS) has been largely ignored by physicians due to a lack of adequate data about the importance of CS enlargement in patients with heart failure (HF). We aimed to assess whether CS dilatation develops in patients with HF and to demonstrate its relation with global myocardial function of the right ventricle (RV). METHODS In this cross-sectional study, 45 healthy subjects and 95 HF patients exhibiting left ventricular systolic dysfunction on echocardiographic examination (EF <45%) secondary to ischemic (n=56) or idiopathic dilated cardiomyopathy (DCM) (n=39) were enrolled. Patients with severe renal dysfunction and/or valve disease were excluded. CS was measured by echocardiography from the posterior atrioventricular groove in the apical four-chamber view. The RV myocardial performance index (MPI), which reflects both systolic and diastolic function of the ventricle, was detected using tissue Doppler imaging, and patients with an RV MPI >0.55 were defined as having impaired RV myocardial function. ANOVA, Kruskal-Wallis, Pearson's correlation, and multivariate logistic regression analyses were used for the statistical analysis. RESULTS The CS and RV MPI values were significantly greater both in patients with ischemic and idiopathic DCM than in controls (8.79±1.7 mm and 8.33±2.1 mm vs. 5.74±0.6 mm, and 0.64±0.07 and 0.62±0.08 vs. 0.43±0.02; p<0.001 for both, respectively). For the prediction of HF patients with impaired RV function, the cut-off value for the diameter of the CS was 7.35 mm, with a sensitivity of 83% and a specificity of 79%. CONCLUSION The CS diameter can be used as a novel echocardiographic marker that provides information about impaired RV function in patients with HF.