Echocardiographic evaluation of left ventricular function in Nigerian adults with systemic hypertension

Objectives: Chronic Hypertension often leads to left ventricular hypertrophy which may be associated with diastolic or in late stage systolic dysfunction. The purpose of the study was to evaluate the extent to which ultrasound might aid the identification of those hypertensive patients who would benefit from early intervention which would improve prognosis.

Methods: 96 Nigerian adults with hypertension were selected and assessed using HP- Sonos CF 100 which is cardiovascular colour flow Doppler ultrasound machines. 2.5MHz transducer was used in standard parasternal long axis, short axis, apical two chambers and four chamber views. Measurements included left ventricular wall thickness, (using both M-mode and 2D). The measurements of the left ventricular posterior wall (LVPW) and inter ventricular septum (IVS) diameter were carried out in ventricular diastole (normal 7–11mm) Left ventricular ejection fraction (EF) was assessed using 2D Simpson's method as a measure of systolic function (normal 50–85%). Assessment of diastolic function was by measurement of E: A ratio using pulsed Doppler to measure mitral valve haemodynamic pattern.

Results: 28 females and 68 males were examined with 2D echocardiographic techniques. 83.33% (n=80) had left ventricular hypertrophy. 58.33% (n=56) had diastolic dysfunction represented by E:A ratio outside the normal reference range and 18.75% (n=18) had systolic dysfunction. The subjects with systolic dysfunction equally had both diastolic dysfunction and LVH as well while the subjects with diastolic dysfunction also had LVH alongside. Only 16patients (15.3%) had no LVH, no diastolic dysfunction and no systolic dysfunction. There was no significant difference in left ventricular abnormalities between patients with hypertension alone compared with those with hypertension and other ailments. There was however, significant statistical difference between diastolic and systolic dysfunction, with diastolic dysfunction occurring more than systolic dysfunction.

Conclusions: The high incidence of left ventricular complications in hypertension s observed in this study can be utilized as evidence for the need for counselling and motivating people to go for screening, as early detection and treatment offers good prognostic outcome and lowers the incidence of left ventricular abnormalities.

Keywords: echocardiography; hypertension; left ventricular hypertrophy; Diastolic dysfunction; systolic dysfunction