CORRELATION BETWEEN SIX-MINUTE WALK TEST AND ECHOCARDIOGRAPHIC PARAMETERS OF LEFT AND RIGHT VENTRICLES IN PATIENTS WITH STABLE SYSTOLIC HEART FAILURECORRELATION BETWEEN SIX-MINUTE WALK TEST AND ECHOCARDIOGRAPHIC PARAMETERS OF LEFT AND RIGHT VENTRICLES IN PATIENTS WITH STABLE SYSTOLIC HEART FAILURE

Abstract

HF is a clinical syndrome characterized by symptoms and signs of increased tissue/organ water and decreased tissue/organ perfusion. The classification of HF patients according to cardiac functional capacity is important to plan the management of the patients' activities, to follow the clinical status of patients over time, to assess the effects of therapeutic interventions and to compare patients with each other (The Criteria Committee of the New York Heart Association, 1994). CPEx testing is regarded as the gold standard for assessment of functional capacity in HF patients (Fleg et al., 2000). However, the 6MWT constitutes a suitable alternative for CPEx testing, with the added benefits of being simple, welltolerated, widely used, and possible to perform under any conditions (Carvalho et al, 2011). Our study was conducted on 40 patients with ICM or DCM (EF <40%) presenting to Ain Shams University hospital rehabilitation clinic with grade I to II NYHA classification. Each patient performed a 6MWT and was then offered an ECG gated Echocardiography study for assessment of systolic and diastolic functions of right & left ventricles. The goal of the study is to determine the correlation between different Echocardiographic variables & functional Summary 149 status “6MWD” in patients with mild & moderate HF “NYHA class I & II”. Comparing the 6MWD of each patient with the different Echocardiographic variables of systolic & diastolic dysfunction revealed that the higher the RVSP the less the 6MWD, the higher the mitral E/E’ ratio the less the 6MWD and the higher the LVESD the less the 6MWD. Moreover, RVSP & E/E’ were significantly higher in patients who walked <300 m. Multivariate analysis of these Echocardiographic variables revealed that RVSP is an independent predictor of 6MWD & thus an independent predictor of functional capacity in HF patients. Accordingly, among different Echocardiographic parameters, one can use RVSP as an independent predictor of functional capacity in HF patients. Furthermore we suggested a predictive model of estimation of 6MWD from a given value of RVSP by applying the linear regression approach on the measured values of RVSP & 6MWD within the patients recruited in our study. Further studies are still needed with larger number of subjects to ascertain the sensitivity & specificity of this model in prediction of functional capacity in HF patients in everyday practice