Acute massive mitral regurgitation from prosthetic valve dysfunction.

Two cases of prosthetic valve dysfunction resulting in acute massive mitral regurgitation are reported; emergency operation was successful in both cases. Survival following complete dislodgement of the occluder of a disc valve, as occurred in one case, does not appear to have been reported before. The diffculty in diagnosis of sudden cardiac decompensation in patients with prosthetic valves is stressed, as is the need for urgent operation.     

Pseudomalfunction of a Beall mitral valve prosthesis in the presence of paravalvular aortic regurgitation.

Premature closure of a Beall mitral valve prosthesis is described in a patient with aortic prosthetic paravalvular regurgitation. Differentiation from valvular malfunction and diagnostic confirmation by means of cinefluoroscopy and simultaneous electrocardiography are discussed.     

二尖瓣成形环瓣环环缩术在缺血性二尖瓣返流中的应用

目的 研究应用二尖瓣成形环行瓣环环缩术治疗缺血性二尖瓣返流的手术效果。方法 选择2000年1月~2015年12月在我院行二尖瓣成形术的缺血性二尖瓣返流并发室壁瘤的患者72例,根据二尖瓣病变部位及性质选择成形方案,其中33例使用二尖瓣成形环进行瓣环环缩术。回顾性分析手术的近期、远期治疗效果。结果 围手术期死亡4例（6%）。术后二尖瓣返流程度较术前明显改善,中度及中度以上二尖瓣返流1例（1%）。术后随访(5±3)年,随访期死亡11例（16%）,出现中度及中度以上二尖瓣返流12例（18%）。是否使用成形环进行瓣环环缩术后早期二尖瓣返流程度无统计学差异,但远期成形环环缩组较对照组二尖瓣返流程度有显著改善（P<0.05）。结论 缺血性二尖瓣返流并发室壁瘤的患者中,二尖瓣成形术可安全、有效地重建二尖瓣功能。使用成形环进行瓣环环缩可改善远期效果。     

Pitfalls of mitral regurgitation assessment in the presence of mitral valve prolapse

Adequate grading of mitral regurgitation (MR) in patients with mitral valve prolapse (MVP) in the presence of mid-late systolic jets can represent a major challenge. In this entity, jets are commonly overestimated by echocardiography. Correct quantification is crucial and highly relevant for the further management and prognosis of these oftentimes young patients. This case points out potential pitfalls and underlines the importance to systematically include qualitative, quantitative, and semi-quantitative parameters into the echocardiographic assessment.     

瓣中瓣置入术治疗二尖瓣关闭不全16例报告

二尖瓣关闭不全患者行常规二尖瓣置换术后常有左室功能恶化，有人推测术中二尖瓣结构的破坏是导致术后左室功能不全的主要机制之一。从１９９１年５月～１９９５年５月，我们对１６例二尖瓣关闭不全患者实施了一种新的二尖瓣置换术，即“瓣中瓣”置入术。术中保留全部二尖瓣瓣叶及瓣下结构，人工瓣置入固定后，前、后瓣叶均卷缩折叠于缝合环下。术后所有患者病情平稳，仅３例需要很少量的正性肌力药物支持，且都能在术后３６小时内脱离呼吸机。经超声心动图测定，术后左室功能很快恢复，所有患者均痊愈出院。结果表明：对二尖瓣关闭不全及其合并轻度狭窄者采用瓣中瓣置入术，有利于术后左室功能的恢复，瓣中瓣置入术是一种安全和有效的手术方法。     

Usefulness of transthoracic echocardiography in detecting significant prosthetic mitral valve regurgitation

To identify the transthoracic echo-Doppler (TTE) variables most predictive of significant mitral regurgitation (MR) of mechanical prosthetic valves, TTE and trans-esophageal echo (TEE) studies were independently reviewed in 57 patients (mean age [+/-SD] 59+/-12.5 years) undergoing both studies within 2+/-3 days. Several 2-dimensional and Doppler hemodynamic variables from the TTE studies were derived. Prosthetic MR was significant (moderate or severe) by TEE in 20 patients, whereas mild or no MR was seen in 37 patients. The best univariate predictors of significant MR by TTE were peak velocity of mitral inflow, mean gradient, tricuspid regurgitation velocity, isovolumic relaxation time, and ratio of time velocity integral of mitral inflow to time velocity integral in the left ventricular outflow (TVI(MV)/TVI(LVO)). Peak mitral velocity and TVI(MV)/TVI(LVO) were the best predictors of significant MR and performed similarly (area under the receiver-operating characteristic curve: 0.97 for both). A peak velocity of > or =1.9 m/s was 90% sensitive and 89% specific for significant prosthetic MR, whereas a TVI(MV)/TVI(LVO) > or =2.5 had a sensitivity and specificity of 89% and 91%, respectively. A decision tree was constructed to assess the conditional probabilities of having significant MR given all the possible outcomes of the 2 best predictors. None of the patients with peak velocity < 1.9 m/s and TVI(MV)/TVI(LVO) <2.5 by TTE had significant MR. Conversely, all patients with peak velocity > or =1.9 m/s and TVI(MV)/TVI(LVO) > or =2.5 had significant MR. The use of more complex algorithms did not further improve the results. Thus, measurements of hemodynamic Doppler variables on TTE examination can accurately identify a large number of patients without significant prosthetic MR, thereby reducing the need for further investigation with TEE.     

Diastolic murmurs in the presence of Starr-Edwards mitral prosthesis.

Diastolic murmurs associated with the Starr-Edwards mitral prosthesis have not been described previously. In this report, five patients with mitral prostheses are described in whom apical mid-diastolic and presystolic murmurs resulted from two different causes. Three patients had clots obstructing the prosthetic orifice. The other two had normally functioning protheses and moderately severe aortic insufficiency. The occurrence of mid-diastolic and presystolic murmurs in the presence of a normally functioning prosthetic mitral valve demonstrates that 1) the mid-diastolic Austin Flint murmur can occur in the absence of incomplete mitral valve opening, premature mitral valve closure, vibrating mitral leaflets, or relative mitral stenosis and 2) the presystolic Austin Flint murmur can occur in the absence of incomplete valve opening or presystolic mitral regurgitation. However, the presystolic murmur was associated with early closure movement of the presthetic poppet.     

Changes in mitral regurgitation after balloon aortic valvuloplasty

The coexistence of mitral regurgitation (MR) in patients with severe aortic stenosis (AS) is not infrequent and has been associated with adverse outcome. The aims of this study were to evaluate the change in MR severity and to identify the correlates of MR improvement in patients with severe AS and moderate to severe MR who underwent balloon aortic valvuloplasty (BAV). Patients with severe AS and at least moderate MR who underwent their first BAV procedures (n = 74) were divided into 2 groups: patients with improved- (n = 34 [46%]) and those without improved (n = 40 [54%]) MR after BAV on transthoracic echocardiography. The population had a mean age of 84 years and was more frequently female (63.5%), with a high risk profile (mean Society of Thoracic Surgeons score 15%, mean European System for Cardiac Operative Risk Evaluation score 57%). Baseline characteristics were balanced between the 2 groups. Patients with improved MR after BAV had smaller left atrial dimensions (45 ± 7 vs 49 ± 7 mm, p = 0.01) and lower peak aortic velocities (3.7 ± 0.6 vs 4.0 ± 0.8 m/s, p = 0.05) and mean transaortic valve gradients (33.2 ± 12.1 vs 40.6 ± 17.4 mm Hg, p = 0.05) at baseline. Left atrial dimension [odds ratio (OR) 3.37, p = 0.006], left ventricular end-diastolic dimension (OR 2.7, p = 0.04), and mean transaortic valve gradient (OR 1.04, p = 0.05), but not left ventricular systolic function or functional MR, were correlated with MR improvement by logistic regression analysis. In conclusion, nearly half of the patients with severe AS and coexistent MR showed improvement in the magnitude of MR after BAV. Larger left atrial and left ventricular end-diastolic dimensions and higher transaortic valve gradients were associated with lack of MR improvement.     

Echocardiographic characteristics and causal mechanism of physiologic mitral regurgitation in young normal subjects

Background: It has become evident that mitral regurgitation (MR) is not uncommon in healthy subjects, and Doppler color flow mapping is a technique that imparts important information relevant to its detection. Hypothesis: Using transthoracic echocardiography, this study evaluated the mechanism of physiologic MR in young normal subjects using transthoracic echocardiography. Methods: The study population consisted of 48 young normal subjects (mean 21 ± 5 years) with MR (physiologic MR group), 40 age-matched young normal subjects (mean 20 ± 5 years) without MR (control group), 45 patients (mean 41 ± 15 years) with mitral valve prolapse with MR (MVP group), and 27 patients (mean 59 ± 13 years) with ruptured chordae tendineae (rupture group). Results: Men were predominant in the rupture group, whereas there were no significant gender differences in the other three groups. Left ventricular end-diastolic dimension and left atrial systolic dimension were slightly smaller in the physiologic MR group than in the control group, but were significantly smaller than those in the MVP and rupture groups. The ratio of the maximum anteroposterior diameter to the maximum transverse diameter on chest radiography and the ratio of the short- to long-axis diameter of the left ventricular cavity at end diastole, determined from two-dimensional short-axis echocardiogram, were significantly lower in the physiologic MR group than in the other three groups. Mitral regurgitation occurred more frequently at the posteromedial commissural site in the physiologic MR and MVP groups, whereas there was no preference for location in the rupture group. Early systolic MR was often observed in the physiologic MR group, whereas pansystolic MR was common in the MVP and rupture groups. Conclusion: As a causal mechanism for physiologic MR detected in young normal subjects, “flattening” of the thorax during growth may cause morphologic abnormalities of the left atrial and ventricular cavities, resulting in spatial imbalance of the mitral complex and resulting in malcoaptation of the valve.