Background: Studies have required large numbers of patients to associate regression of left ventricular (LV) mass with a decrease in brachial cuff blood pressure (BP) in the treatment of hypertension. Hence, we prospectively examined potential superiority of pulse wave analysis over conventional BP measurement in predicting treatment-induced LV mass reduction.
Methods: Forty-six untreated patients (mean age, 56 +/- 7 years) with hypertension received standard medical treatment based on international guidelines. Echocardiography and measurements of various LV load indices were made before and after 1 year of treatment.
Results: Antihypertensive treatment significantly (P < .05) reduced LV load, manifest by a decrease in measured brachial BP, estimated aortic BP, carotid-femoral pulse wave velocity (PWV(cf)), aortic augmentation index (AI(a)), aortic augmented pressure (AugP), and radial augmentation index (AI(r)). These changes were accompanied by significant reduction in LV mass index (LVMI) and improvements in systolic ejection fraction and diastolic early-to-atrial ratio of transmitral flow velocities. The treatment-induced LVMI change was not correlated with changes in brachial BP or PWV(cf), but was closely correlated with factors influenced by wave reflection - changes in AI(a), AI(r), AugP, and aorta-to-arm pulse pressure amplification. On multivariate analysis, AI(a) change was the strongest determinant of LVMI change, independent of brachial BP and PWV(cf) changes (beta = 0.51, P < .001). Estimated subject numbers required for predicting a significant LVMI reduction were far less when wave reflection-related factors were used rather than conventional bracial BP.
Conclusions: These results suggest that reduction in wave reflection is an important therapeutic strategy for reducing LV mass, which can be predicted with modest subject numbers.