Aortic valve replacement in patients with aortic valve stenosis improves myocardial metabolism and diastolic function

PURPOSE: To evaluate whether functional and metabolic changes recover after aortic valve replacement (AVR). MATERIALS AND METHODS: Eighteen men with aortic valve stenosis (mean pressu re gradient +/- SD, 79.9 mm Hg +/- 15.1) underwent magnetic resonance (MR) imaging and phosphorus 31 MR spectroscopy. In nine patients who underwent A VR, MR imaging and spectroscopy were repeated 40 weeks +/- 12 after AVR. Te n age-matched healthy men were control subjects. RESULTS: Before AVR, the myocardial phosphocreatine (PCr)-to-adenosine trip hosphate (ATP) ratio in the 18 patients was 1.24 +/- 0.17 and 1.43 +/- 0.14 in the control group (P < .01). in nine patients who underwent follow-up M R spectroscopy, the ratio increased from 1.28 +/- 0.17 to 1.47 +/- 0.14 (P < .05) following AVR. Before AVR, early acceleration peak corrected for car diac output was (0.043 +/- 0.008) x 10(-3) sec(-1) in patients and (0.081 /- 0.033) x 10(-3) sec(-1) in the control group (P < .05). After 40 weeks /- 12, the mean early acceleration peak corrected for cardiac output in the nine patients increased significantly to (0.055 +/- 0.006) x 10(-3) sec(-1 ) (P < .05), although it was still significantly lower than that of the con trol group (P < .05). Before AVR, a significant correlation was found betwe en the myocardial PCr-ATP ratio and left ventricular diastolic function (n = 18; P < .05). CONCLUSION: Severe aortic valve stenosis leads to a decreased myocardial PC r-ATP ratio and impairment of left ventricular diastolic function; followin g AVR, the ratio normalizes completely, whereas function improves significa ntly. There is an association between altered myocardial high-energy phosph ate metabolism and impaired left ventricular diastolic function.