Rajappan Kim, Bellenger Nicholas G, Melina Giovanni, Di Terlizzi Marco, Yacoub Magdi H, Sheridan Desmond J, Pennell Dudley J
Cardiovascular MR Unit, Royal Brompton Hospital, Sydney Street, London, UK.
Eur J Cardiothorac Surg. 2003 Jul;24(1):59-65. doi: 10.1016/s1010-7940(03)00183-0.
In patients with aortic valve disease, the presence of left ventricular hypertrophy (LVH) carries a significant risk of adverse cardiovascular events. Regression of hypertrophy after aortic valve replacement (AVR) is associated with a reduction in risk. In general, M-mode echocardiography has been used for quantitative assessment of left ventricular mass (LVM) and regression, but this technique is believed to have limitations from which cardiovascular magnetic resonance (CMR) does not suffer. The objective of this study therefore was to determine whether quantitative assessment of LVM and regression after AVR using the two techniques was comparable.
Thirty-nine patients with aortic valve disease were studied before and 1 year after AVR. Transthoracic M-mode echocardiography and four different formulae were used to calculate left ventricular mass index (LVMI), and then compared with CMR measurements.
Overall, correlation between the techniques for single measurement of LVMI was moderate (r-values from 0.64 to 0.69), with a tendency for overestimation by echocardiography; there was no agreement in degree of regression (r-values from 0.004 to 0.18). The Bland-Altman limits of agreement ranged from 85 to 131% for single measurement of LVMI, and 328-470% for regression. The change in LVMI with CMR was 43+/-28 g/m2, vs. 27 to 54+/-19 to 41 g/m2 using echocardiography.
M-mode echocardiography does not provide reliable quantification of regression of LVH in individuals, and for accurate measurement CMR is superior. The use of CMR in future studies may reduce costs since fewer subjects are needed to accurately detect significant changes in LVMI after AVR.
在主动脉瓣疾病患者中，左心室肥厚（LVH）的存在会带来显著的不良心血管事件风险。主动脉瓣置换术（AVR）后肥厚的消退与风险降低相关。一般来说，M型超声心动图已被用于左心室质量（LVM）和消退的定量评估，但该技术被认为存在局限性，而心血管磁共振（CMR）则不存在这些局限性。因此，本研究的目的是确定使用这两种技术对AVR后LVM和消退进行定量评估是否具有可比性。
对39例主动脉瓣疾病患者在AVR术前和术后1年进行研究。使用经胸M型超声心动图和四种不同公式计算左心室质量指数（LVMI），然后与CMR测量结果进行比较。
总体而言，两种技术单次测量LVMI的相关性中等（r值为0.64至0.69），超声心动图有高估的趋势；在消退程度方面没有一致性（r值为0.004至0.18）。单次测量LVMI的Bland-Altman一致性界限为85%至131%，消退的一致性界限为328%至470%。CMR测量的LVMI变化为43±28 g/m²，而超声心动图测量的变化为27至54±19至41 g/m²。
M型超声心动图不能为个体LVH消退提供可靠的定量评估，而CMR在准确测量方面更具优势。在未来的研究中使用CMR可能会降低成本，因为准确检测AVR后LVMI的显著变化所需的受试者数量更少。
