Diltiazem slow-release and left-ventricular hypertrophy: a volumetric approach of left ventricular mass using magnetic resonance imaging.

AIMS

This study was designed to assess the changes in left ventricular mass (LVM) in hypertensive patients with left ventricular hypertrophy under drug therapy with once-daily slow-release diltiazem. Magnetic resonance imaging (MRI) was used for this purpose because of its higher reproducibility than M-mode or two-dimensional echocardiography.

METHODS

Patients suffering from essential hypertension were included if their baseline LVM index (LVMI) was > or = 105 g/m2 in male or > or = 85 g/m2 in female patients, ie, equal or higher to the median values observed in hypertensive patients in our institution. MRI consisted in a true short-axis, electrocardiogram (ECG) gated spin-echo slice acquisition at baseline, after 3 and 6 months of therapy (M0, M3, and M6). Data were stored on magnetic tapes and read subsequently under blind conditions and the control of an external auditor.

RESULTS

Thirty-five patients were included. Of these, 14 patients (40%) were not previously treated. Inter- and intra-observer variability for LVMI measurement were 5.6 +/- 4.3% and 2.1 +/- 3.0%, respectively. Mean baseline LVMI was 110 +/- 16 g/m2 in male and 96 +/- 16 g/m2 in female patients. It decreased by 3.6% at M3 (P = 0.05) and by 6.0% at M6 (P = 0.02). A trend towards a greater LVMI reduction was observed in previously untreated patients.

CONCLUSION

This study confirms that MRI is a reproducible technique for the measurement of LVM. It demonstrates a significant reduction in LVMI as early as the 3rd month of therapy in hypertensive patients treated with once-daily sustained release (SR) diltiazem, although baseline LVMI in the majority of participating patients was only moderately increased.