CARDIOVASCULAR JOURNAL OF AFRICA • Volume 34, No 4, September/October 2023 AFRICA 223 the measured RV FAC. The LVOT VTI was particularly well correlated with the RV FAC and was the strongest independent predictor of RV FAC in the final multivariate linear regression model. The LVOT VTI, a Doppler-derived measure of the distance travelled by midstream blood through the LV outflow tract in a single cardiac cycle, is a relatively simple parameter that serves as a proxy estimate of forward stroke volume.27 It is easily reproducible with low interobserver variability and can be incorporated into a routine echocardiographic examination with little additional resources or time.28 In our study, an LVOT VTI < 9.8 cm in patients with left HF was found on ROC analysis to be the cut-off value for a RV FAC < 35% with a sensitivity of 81.5% and specificity of 81.9%. Apart from RV FAC, RVSD measured by RV S′, TAPSE and RVMPI were significantly worse in males with left HF compared with females. Other studies have previously reported no gender difference in RVSD.29 The reason for the gender disparity in RV S′, TAPSE and RV MPI observed in the current study is not immediately apparent and is not explained by HF severity or aetiology. A possible reason is the varied cut-off values used to define RVSD in these studies. This underscores the importance of more normative studies to define the optimal cut-off limits of normal RV function in indigenous Africans. We did not find an association between patient’s age and the presence of RVSD in this study. The study had some limitations. Being hospital-based and involving a single centre limits the generalisability of the results. Cardiac magnetic resonance imaging (MRI) has emerged as the most accurate technique to quantify RV size and function.30 However, the cost implications and limited access to cardiac MRI make it less suitable for routine clinical purposes in a resourceconstrained setting. Echocardiography, despite its limitations, is widely available, affordable and has acceptable sensitivity. Determination of HF aetiology was based on clinical features, ECG and echocardiographic findings. Information about coronary anatomy and functional ischaemia tests were not routinely available so it is conceivable that some participants with significant ischaemic heart disease were not identified as such. Additionally, TAPSE is not a validated index for assessing RV function in the presence of atrial fibrillation. While the number of patients with atrial fibrillation in this study was relatively low (7.0%), this limitation must be borne in mind in interpreting findings that are based on TAPSE measurements. Conclusion RV systolic dysfunction was common in these Ghanaian patients with left HF. Worsening LV systolic and diastolic function, higher PASP and a low systemic SBP were predictors of the presence of RVSD, which was more common among patients with non-hypertensive HF. 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