Aim: To determine if Color Doppler myocardial imaging could provide evidence of diastolic dysfunction in patients with hypertension whose pulse-wave Doppler parameters were normal.
Method: The study included 33 patients (mean age 48+/-7.3 years) and a control group of 13 sex- and age-matched healthy individuals. Patients were divided into two groups according to mean blood pressure (BP) values during 24-hour blood pressure monitoring while under antihypertensive therapy: those with uncontrolled hypertension (n=22) and those with controlled hypertension (n=11). All study participants underwent complete standard echocardiography (2D, M-mode, pulsed and continuous Doppler) and a Color Doppler myocardial imaging study.
Results: Conventional Doppler parameters indicated relaxation disturbances in patients with uncontrolled hypertension, but were within a normal range in patients with controlled hypertension at baseline and follow-up. Parameters of global diastolic function measured by Color Doppler myocardial imaging revealed that E'/A', the ratio between E'-wave (early filling phase) and A'-wave (late diastolic wave due to atrial contraction), was <1 in 57% of segments at baseline in patients with uncontrolled hypertension, and did not significantly change at follow-up. In patients with controlled hypertension, E'/A'<1 was noted in 4.7% of segments at baseline and in 28.6% of segments at follow-up.
Conclusion: Regional diastolic dysfunction measured by Color Doppler myocardial imaging was the first sign of myocardial dysfunction due to arterial hypertension, while the parameters of global diastolic dysfunction measured by conventional Doppler and Color Doppler myocardial imaging were still normal. Furthermore, in patients with uncontrolled hypertension with manifested global diastolic dysfunction, there was a change in late diastolic parameters. Our results point to a potentially important role of Color Doppler myocardial imaging in diagnosing hypertensive heart disease as well as in follow-up of treatment.