Casset-Senon D, Babuty D, Philippe L, Fauchier L, Eder V, Fauchier J P, Pottier J M, Delhomme C, Cosnay P
Nuclear Medicine Department, Trousseau Hospital, Tours, France.
J Nucl Cardiol. 2000 Sep-Oct;7(5):471-7. doi: 10.1067/mnc.2000.107242.
Ventricular premature beats are common in patients with mitral valve prolapse (MVP). The purpose of this study was to determine whether symptomatic patients with MVP had certain functional characteristics and if ventricular arrhythmia (VA) could be explained by functional extravalvular abnormalities. Single photon emission computed tomography equilibrium radionuclide angiography with Fourier phase analysis was preferred to the planar radionuclide method. Only patients without significant mitral regurgitation were studied.
A total of 23 symptomatic patients with MVP (13 men, 10 women, mean age, 47+/-14 years) without mitral regurgitation underwent single photon emission computed tomography equilibrium radionuclide angiography. Symptoms were present in 20 patients, and VA was present in 14 patients. Ejection fraction, regional wall motion, and Fourier phase analysis were examined in both ventricles and compared with results for normal subjects. Ventricular abnormalities were observed in 20 (87%) patients: decreased left ventricular and right ventricular ejection fractions, increased standard deviations of the mean phase and focal wall motion, and/or delayed phase abnormalities. Abnormalities were less frequent but more marked in the right ventricular free wall, the infundibulum, or the septum compared with left ventricular delayed abnormalities, which were more frequent but limited. In 12 of 14 patients with VA, phase-delayed areas were observed in the ventricle where the origin of ventricular premature beats was suspected on the basis of their electrocardiographic morphologic features. A relation was found between late potentials and delayed-phase areas (right ventricle or septum) and left bundle branch block morphologic features of VA.
Symptomatic patients with MVP frequently have ventricular dysfunction in 1 or both ventricles, sometimes limited but more marked in the presence of severe VA even without significant mitral regurgitation, suggesting structural modification. The use of a sensitive, accurate, and 3-dimensional method such as single photon emission computed tomography equilibrium radionuclide angiography may be of interest for a noninvasive investigation, especially in young symptomatic patients with MVP and VA.
室性早搏在二尖瓣脱垂（MVP）患者中很常见。本研究的目的是确定有症状的MVP患者是否具有某些功能特征，以及室性心律失常（VA）是否可由功能性瓣膜外异常来解释。与平面放射性核素方法相比，采用傅里叶相位分析的单光子发射计算机断层扫描平衡放射性核素血管造影术更受青睐。仅对无明显二尖瓣反流的患者进行了研究。
共有23例有症状的无二尖瓣反流的MVP患者（13例男性，10例女性，平均年龄47±14岁）接受了单光子发射计算机断层扫描平衡放射性核素血管造影术。20例患者有症状，14例患者有VA。对双心室的射血分数、局部室壁运动和傅里叶相位分析进行了检查，并与正常受试者的结果进行比较。20例（87%）患者观察到心室异常：左心室和右心室射血分数降低、平均相位标准差和局部室壁运动增加，和/或相位延迟异常。与左心室延迟异常相比，右心室游离壁、漏斗部或室间隔的异常较少见但更明显，左心室延迟异常更常见但程度较轻。在14例有VA的患者中的12例中，根据心电图形态特征怀疑室性早搏起源的心室中观察到相位延迟区域。发现晚期电位与延迟相位区域（右心室或室间隔）以及VA的左束支传导阻滞形态特征之间存在关联。
有症状的MVP患者经常在一个或两个心室出现心室功能障碍，有时即使没有明显的二尖瓣反流，在严重VA存在时也会出现功能障碍，虽然有时受限但更明显，提示结构改变。使用敏感、准确的三维方法，如单光子发射计算机断层扫描平衡放射性核素血管造影术，可能对无创性检查有意义，特别是对于有症状的年轻MVP和VA患者。
