LAUSR

significance. The decrease in LA volume index and the decrease in E/e0 mean at rest in the spironolactonetreated group support this possibility, whereas the lack of changes in E/A and deceleration time do not. Unfortunately, the tricuspid regurgitation peak velocity, an important component in the estimation of resting LA pressure (2), was notmeasured in this study. A further concern is that the standard deviations were not provided for any of the echocardiographic variables, and thus perspective is lacking regarding the variability in the resting LA pressures. The values for E have not been provided, and it is therefore not clear whether the decrease in E/e0 was a result of changes in both E and e0, as had been previously reported (3). An additional issue is that the increase in the resting lateral e0 in the spironolactone-treated group could have been directly related to blood pressure (BP) reduction, for which having a BP level at the precise time of the imaging could be critical (4); however, the timing of BP measurement is not mentioned. Although serial biopsy data would be the gold standard (5), information pertinent to whether MRArelated change in fibrosis is a contributor to the positive findings with spironolactone could be obtained in future studies if an earlier repeat exercise study was performed (e.g., after 2 weeks of treatment). As appropriate diuretic therapy in patients with heart failure with preserved ejection fraction can result in a reduction in LA pressure and improvement in exertional symptoms within days, if findings similar to those of the present study relating to exercise tolerance, E, e0, and E/e0 were evident after 2 weeks, then a contribution from MRA through regression of left ventricular fibrosis could be excluded.