Does the Myocardial Performance Index Affect Pulmonary Artery Pressure in Patients With Mitral Stenosis? A Tissue Doppler Imaging Study

BACKGROUND: The relation between systolic pulmonary artery pressure (PAP) and mitral stenosis (MS) has been poorly understood. Although the mitral valve area (MVA) is an important factor affecting the PAP, there is a wide spectrum of the PAP in patients with MS despite a similar MVA. So, we analyzed whether the left and right ventricular myocardial performance index (MPI) correlated with the PAP. METHODS: Two-dimensional Doppler echocardiography was performed in 46 patients with MS. The left atrial diameter, mean mitral gradient, and MVA were measured. The PAP was derived from the tricuspid regurgitant jet velocity. The ejection time (ET), isovolumetric relaxation time (IRT), and contraction time (ICT) were measured on annulus of interventricular septum, lateral, inferior and anterior wall of left ventricle, and right ventricle free wall from apical two- and four-chamber views in patients with MS and 40 age-matched healthy patients by tissue Doppler imaging (TDI). Then the MPI was calculated as (IRT + ICT)/ET for both left and right ventricle. The correlation of PAP with MVA, mean mitral gradient, left atrial diameter, and left and right ventricular MPI was evaluated. RESULTS: MVA and PAP were measured as 1.57 +/- 0.39 cm2 (0.8-2.5 cm2)and 42 +/- 16 mmHg, respectively. It was determined that the MPI increased in patients with MS(0.59 +/- 0.1 vs 0.48 +/- 0.07, P < 0.001). It was also demonstrated that the MVA, left atrial diameter, mean diastolic gradient, and left ventricular MPI were correlated with PAP(r =-0.39 [P = 0.007], r = 0.43 [P = 0.003], r = 0.58 [P < 0.001], and r = 0.65 [P < 0.001], respectively). In multivariate analysis, although the PAP correlated with mean diastolic gradient and MPI (r = 0.39 [P = 0.013], and r = 0.48 [P < 0.001]), it did not correlate with left atrial diameter and MVA. The PAP also correlated with right ventricular MPI(r = 0.63 [P < 0.001]). CONCLUSION: This study demonstrates that the left ventricular MPI obtained by TDI is an important marker of PAP, and right ventricular MPI correlates with the PAP in patients with MS.     

Color Doppler tissue imaging to evaluate left atrial appendage function in mitral stenosis

Two-dimensional color Doppler tissue imaging (CDTI) has so far been used, in general, to evaluate ventricular function. This study examined if the left atrial appendage tissue velocity could reproducibly be measured with CDTI and if they have any predictive value for left atrial appendage (LAA) function and former thromboembolism. Thirty-six patients (24 women, 12 men; mean age 45 +/- 12 years; 18 AF; 11 former thromboembolic stroke) with mitral stenosis undergoing transesophageal echocardiography were examined with CDTI. Peak systolic tissue velocity (m/sec, peak systolic velocity [PSV]) was measured at the tip of the LAA in the basal short-axis view. LAA flow emptying (LAAEV) and filling (LAAFV) velocities (m/sec) were also recorded 1 cm immediately below the orifice of the appendage. Interobserver and intraobserver variabilities were determined for the PSV. LAA ejection fraction was measured by Simpson's method. Mitral regurgitation, AF, transmitral mean gradient, left ventricular ejection fraction, mitral valve area, and left atrial diameter were used as a covariant for adjustment. The intraobserver and interobserver correlation coefficients for the PSV using CDTI was 0.64 and 0.60, respectively (bothP = 0.01). LAAEV(0.29 +/- 0.09 vs 0.19 +/- 0.04, P = 0.001)and LAA ejection fraction(44 +/- 12 vs 29 +/- 14, P = 0.004)were found to be significantly decreased in the patients with decreased PSV (<0.05 m/sec), even after adjustment. The decreased PSV was positively correlated with the low LAAEV (<0.25 m/sec) and history of thromboembolism (r = 0.59, r = 0.38, respectively), and remained a significant determinant of the low LAAEV (OR 50.03, CI 1.46-1738.11,P = 0.02), but not of history of thromboembolism (OR 4.29, CI 0.52-35.01,P = 0.08) after adjustment. In conclusion, these results suggest that CDTI provides a reproducible method for quantification of contraction at the tip of the LAA. Decreased PSV may be predictive of poor LAA function.     

法洛四联症伴肺动脉瓣缺如3例报道并文献复习

目的总结法洛四联症伴肺动脉瓣缺如患儿的临床特点和诊治经验。方法收集复旦大学附属儿科医院2007年11月至2009年2月收治的法洛四联症伴肺动脉瓣缺如3例患儿的临床资料,总结其临床表现、影像学特征、治疗和预后。结果男1例,女2例,年龄39 d至4个月。临床均表现为气急、咳喘及轻度发绀;体检可闻及胸骨左缘来回杂音。超声心动图和心导管检查除法洛四联症表现外,可见肺动脉瓣环发育不良或缺如,伴肺动脉重度反流、肺动脉瘤样扩张,均未见动脉导管未闭,其中1例左肺动脉不连接伴发育不良。2例临床症状严重的患儿施行手术根治,其中1例手术效果满意,另1例左肺动脉不连接伴发育不良患儿术中死亡;1例患儿临床症状尚不明显,仍在密切随访中。结论法洛四联症伴肺动脉瓣缺如尽管少见,但由于在婴儿期甚至新生儿期即可引起严重气道受压从而危及生命,临床中遇到难以控制的呼吸窘迫新生儿和小婴儿应考虑本病的可能。尽早手术根治解除气道受压呼吸困难症状是唯一的治疗方法,无呼吸道受压症状可考虑6个月左右择期手术。手术病死率高于单纯法洛四联症,尤其是伴一侧肺动脉不连接或发育不良的患儿。     

二尖瓣环钙化与颈动脉粥样硬化关系的超声研究

目的 了解二尖瓣环钙化（MAC）与颈动脉粥样硬化之间的关系，探讨MAC能否作为颈动脉粥样硬化的独立预测因子。方法 采用高频超声对156例MAC患者（其中55例为重度MAC患者）及118例年龄、性别与之相匹配的无MAC对照者的颈动脉进行了检测。结果 ①与对照组比较，MAC组及重度MAC组患者高血压和糖尿病的患病率明显增加（P〈0．05）；②MAC组颈动脉粥样硬化斑块发生率，颈动脉狭窄≥20％、≥40％及双侧颈动脉狭窄≥40％的发生率均显著高于对照组（P〈0．01），重度MAC组上述指标的改变更为显著（P〈0．01）。此外，重度MAC组颈动脉狭窄≥60％的发生率明显高于对照组（P〈0．05）；③MAC组及重度MAc组颈动脉内-中膜厚度（IMT）显著高于对照组（P〈0．01）；④单因素及多因素Logistic回归分析结果均表明：MAC是颈动脉狭窄≥40％最有意义的预测因子（P〈0．01）。结论 MAC与颈动脉粥样硬化之间存在十分密切的关系，通过对MAC的检测，能够预测颈动脉粥样硬化的存在及其程度，在临床实际工作中，对于有二尖瓣环钙化的患者应常规进行颈动脉粥样硬化的检查。     

Doppler echocardiography assessment of prosthetic heart valves

Transthoracic Doppler echocardiography is an accurate noninvasive method for the evaluation of prosthetic valve function. The flow characteristics and pressure gradients of normally functioning mechanical and bioprosthetic valves have been, in general established. Normal functioning mitral valve prostheses have a valve area > 1.8 cm² with the St. Jude valve having the largest effective valve area and normally functioning aortic prosthetic valves have a peak instantaneous gradient of < 45 mmHg, with the Starr-Edwards valves (Starr-Edwards, Irvine CA) showing the highest gradients. The incidence of minimal or mild regurgitation is approximately 15% to 30% in the mitral position and 25% to 50% in the aortic position, with the higher incidence of regurgitation seen with mechanical compared to bioprosthetic valves. Transthoracic Doppler echocardiography can accurately detect patients with prosthetic valvular stenosis. The presence of prosthetic aortic regurgitation can also generally be accurately assessed, except in the presence of both prosthetic aortic and mitral valves. Assessment of prosthetic mitral regurgitation remains limited due to significant attenuation of the ultrasound beam by the prosthesis and the frequent underestimation of severity of regurgitation. Other limitations of transthoracic studies include assessment of leaflet morphology, detection of vegetations and valve abscesses, and differentiation between valvular and paravalvular regurgitation.     

Anti-Ro/SSA antibodies are associated with severe mitral valve regurgitation in patients with systemic lupus erythematosus

Objective: To assess whether anti-Ro/SSA antibodies are associated with cardiac valve disease in lupus.

Methods: A single-center, medical chart review was performed. Lupus patients were divided according to its anti-Ro/SSA status and subgroups were compared for valvular abnormalities and other characteristics. Dependence of anti-Ro/SSA reactivity to anti-Ro52/TRIM21 antibodies was also evaluated.

Results: Eighty-nine lupus patients were analyzed. The most common valvular abnormalities were tricuspid (60%), mitral (41%) and pulmonary (14%) regurgitation. Thirty-six patients were positive and 53 negative for anti-Ro/SSA antibodies. In patients positive to anti-Ro/SSA, a difference was noted for anti-dsDNA (67 versus 45%; p?=?0.04) and anti-La/SSB (19 versus 2%; p?=?0.004) antibodies. An association between anti-Ro/SSA antibodies and severe mitral regurgitation was observed; indeed, 4/15 patients with anti-Ro/SSA and mitral regurgitation had severe forms of valvulopathy as compared to only 1/22 patients with mitral regurgitation but negative to such antibody (27 versus 5%; p?=?0.02). Anti-Ro/SSA antibodies significantly elevated the risk of severe mitral regurgitation (OR?=?5). Anti-Ro52/TRIM21 levels (103?±?29 versus 42?±?43?U/mL; p?=?0.03) and anti-Ro52/TRIM21:?anti-Ro/SSA ratios (0.88?±?0.02 versus 0.35?±?0.37; p?=?0.03) were higher in patients with mitral valve regurgitation than in those with no valvulopathy.

Conclusion: Anti-Ro/SSA antibodies, mainly against Ro52/TRIM21 antigens, may be pathologically involved in lupus-associated mitral valve regurgitation.     

Incidence and Predictors of Permanent Pacemaker Requirement after Transcatheter Aortic Valve Implantation with a Self‐Expanding Bioprosthesis

Background: Previous reports have suggested the occurrence of cardiac conduction disorders and permanent pacemaker (PPM) requirement after transcatheter aortic valve implantation (TAVI). Based on a single‐center experience, we aim to assess the incidence of postprocedural conduction disorders, need for PPM, and its determinants after TAVI with a self‐expanding bioprosthesis. Methods: From August 2007 to October 2009, 32 consecutive patients underwent TAVI with the Medtronic CoreValve (MCV) System (Medtronic Inc., Minneapolis, MN, USA). Three patients paced at baseline and two cases of procedure‐related mortality were excluded. We analyzed the 12‐lead electrocardiogram at baseline, immediately after procedure and at discharge. Requirements for PPM were documented and potential clinical, electrophysiological, echocardiographic, and procedural predictors of PPM requirement were studied. Results: After TAVI, eight patients (29.6%) required PPM implantation due to high‐grade atrioventricular (AV) block. The prevalence of left bundle branch block increased from 13.8% to 57.7% directly after implantation (P = 0.001). Need for PPM was correlated to the depth of prosthesis implantation (r = 0.590; P = 0.001). At a cutoff point of 10.1 mm, the likelihood of pacemaker could be predicted with 87.5% sensitivity and 74% specificity and a receiver operator characteristic curve area of 0.86 ± 0.07 (P = 0.003). Of the seven patients with preexisting right bundle branch block (RBBB), four (57.1%) required PPM implantation after TAVI. Conclusions: High‐grade AV block requiring PPM implantation is a common complication following TAVI and could be predicted by a deeper implantation of the prosthesis. Patients with preexisting RBBB also seem to be at risk for the development of high‐grade AV block and subsequent pacemaker implantation. (PACE 2010; 1364–1372)