Rittoo D, Sutherland G R, Shaw T R
Department of Cardiology, Western General Hospital, Edinburgh, UK.
Cardiology. 1998 Mar;89(3):202-9. doi: 10.1159/000006788.
Mitral regurgitation which is more than mild in severity is usually regarded as a relative contraindication to balloon mitral commissurotomy (BMC) because it is commonly believed that it may be worsened by the procedure. The aim of this study was to investigate the effects of BMC on pre-existing mitral regurgitation. Transthoracic and biplane transoesophageal echocardiography (TTE, TEE) combined with colour flow mapping (CFM) were performed prospectively on 50 consecutive patients immediately before and within 24 h after Inoue BMC. Before BMC, mitral regurgitation (MR) was diagnosed by TEE and left ventriculography in 36 and 13 patients respectively. Angiographic MR was mild in all 13 cases. The precise origins of MR jets were carefully sought by scanning in multiple TTE and TEE views. The maximal area of colour flow MR jets detected by TEE was measured by planimetry. After BMC mean mitral valve area increased from 1.0 +/- 0.3 to 1.7 +/- 0.8 cm2, p < 0.0001, mean left atrial pressure and volume decreased from 23.7 +/- 5.6 mm Hg to 21.6 +/- 7.5 ml, p = 0.039, and from 105 +/- 56 to 90 +/- 46 ml, p = 0.002, respectively. MR jets as assessed by TEE CFM disappeared in 12 patients, in all of whom MR had been undetected by angiography. MR jets remained within 20% of their original sizes in 16 (44%) patients and more than doubled in only 3 patients. However, the latter had only mild angiographic MR after BMC. BMC created new MR jets, distinct from pre-existing ones, in 27 (75%) patients. Their aetiologies were commissural splitting in 24, leaflet tears in 2 and chordal rupture in 1 case. New MR jets were co-existent with old jets in 17 (47%) cases and in 10 (28%) cases old jets were replaced by new jets. The severity of angiographic MR was unchanged in 21 (58%) of the 36 patients; new jets, all originating from one or both commissures, were found in 13 (65%) patients on TEE. Angiographic MR increased by 1 grade in 11 (33%) patients; new jets were detected in 9 patients, 8 from the commissures and 1 due to chordal rupture; in only 1 of the 11 patients did the increase in MR appear to be due to a worsening of a pre-existing jet. Angiographic MR increased by 2 grades in 3 (8%) patients; new jets appeared in all 3, arising from the commissures in 2 and from a leaflet tear in 1 case. One patient with a leaflet tear sustained an increase of 3 grades in angiographic MR. The final degree of angiographic MR was nil in 13, mild in 15, moderate in 6 and severe in 2 patients. Leaflet tears were responsible for both cases of severe MR. BMC does not appear to affect pre-existing mitral regurgitation adversely in almost all patients. It may abolish trivial jets but in most cases it creates new jets alongside the old ones. Leaflet tears are responsible for severe mitral regurgitation after BMC and this is independent of pre-existing regurgitant jets.
中重度以上的二尖瓣反流通常被视为经皮球囊二尖瓣交界切开术（BMC）的相对禁忌证，因为人们普遍认为该手术可能会使二尖瓣反流恶化。本研究的目的是探讨BMC对术前已存在的二尖瓣反流的影响。对50例连续患者在Inoue BMC术前即刻及术后24小时内进行了经胸和双平面经食管超声心动图（TTE、TEE）检查，并结合彩色血流图（CFM）。在BMC术前，分别通过TEE和左心室造影诊断出36例和13例二尖瓣反流（MR）患者。13例患者的血管造影显示MR均为轻度。通过在多个TTE和TEE视图中扫描仔细寻找MR喷射的精确起源。通过平面测量法测量TEE检测到的彩色血流MR喷射的最大面积。BMC术后二尖瓣平均瓣口面积从1.0±0.3增加到1.7±0.8 cm2，p<0.0001，平均左心房压力和容积分别从23.7±5.6 mmHg降至21.6±7.5 ml，p = 0.039，以及从105±56降至90±46 ml，p = 0.002。经TEE CFM评估，12例患者的MR喷射消失，其中血管造影均未检测到MR。16例（44%）患者的MR喷射保持在其原始大小的20%以内，仅3例患者的MR喷射增加了一倍以上。然而，后3例患者在BMC术后血管造影显示MR仅为轻度。BMC在27例（75%）患者中产生了与术前不同的新的MR喷射。其病因分别为瓣叶交界裂开24例、瓣叶撕裂2例和弦索断裂1例。17例（47%）患者新的MR喷射与旧的喷射并存，10例（28%）患者旧的喷射被新的喷射取代。36例患者中有21例（58%）血管造影显示的MR严重程度未改变；13例（65%）患者在TEE上发现新的喷射，均起源于一个或两个瓣叶交界。11例（33%）患者血管造影显示的MR增加1级；9例患者检测到新的喷射，8例起源于瓣叶交界，1例由于弦索断裂；11例患者中只有1例MR的增加似乎是由于术前喷射恶化所致。3例（8%）患者血管造影显示的MR增加2级；3例均出现新的喷射，2例起源于瓣叶交界，1例由于瓣叶撕裂。1例瓣叶撕裂患者血管造影显示的MR增加3级。最终血管造影显示的MR程度为无反流13例、轻度15例、中度6例和重度2例。重度MR的2例均由瓣叶撕裂所致。BMC似乎在几乎所有患者中都不会对术前已存在的二尖瓣反流产生不利影响。它可能消除微量喷射，但在大多数情况下会在旧的喷射旁产生新的喷射。瓣叶撕裂是BMC术后重度二尖瓣反流的原因，且与术前存在的反流喷射无关。
