A larger aortic annulus causes aortic regurgitation and a smaller aortic annulus causes aortic stenosis in bicuspid aortic valve

A bicuspid aortic valve (BAV) often causes aortic stenosis (AS) or regurgitation (AR). In 54 patients with a BAV (48 +/- 16 years), transthoracic and transesophageal echo were performed to measure aortic annulus diameter (AAD), to evaluate the severity of aortic valve disease (AVD) and to calculate the area eccentricity index (AEI) of a BAV defined as a ratio of the larger aortic cusp area to a smaller aortic cusp area. By multiple linear regression analysis, the severity of AR correlated significantly with the AAD (r = 0.38) and AEI (r = 0.35) (P < 0.05) and that of AS correlated significantly with the AAD (r =-0.40) and AEI (r = 0.34) (P < 0.05). Thirty-six patients showed anteroposteriorly (A-P) located BAVs and 18 patients showed right-left (R-L) located BAVs. The AAD was larger in A-P type than in R-L type (15 +/- 3 vs 13 +/- 2 mm/BSA, P < 0.05) and there was no difference in the age and AEI between the two groups. AR was more severe in A-P type than in R-L type while AS was more severe in R-L type than in A-P type (P < 0.05). Twenty-nine patients showed raphes. The AEI was larger in raphe (+) type than in raphe (-) type (1.83 +/- 0.53 vs 1.51 +/- 0.47, P < 0.05) and there was no difference in the AAD and severity of AVD between the two groups. In conclusion, a BAV with larger aortic annulus or A-P located will tend to cause AR while a BAV with smaller aortic annulus or R-L located will tend to cause AS.     

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文章论述主动脉夹层(AD)、主动脉壁间血肿(出血)、主动脉穿透性溃疡的影像学诊断的进展,并讨论三者的关系,提出影像学检查在诊断和鉴别诊断中具有重要的作用。     

In-vitro comparison of aortic valve hemodynamics between aortic root remodeling and aortic valve reimplantation

BACKGROUND AND AIM OF THE STUDY: Valve-preserving aortic replacement has become an accepted option for patients with aortic valve regurgitation and aortic dilatation. The relative role of root remodeling versus valve reimplantation inside a vascular graft has been discussed, albeit controversially. In the present study, an in-vitro model was used to investigate the aortic valve hemodynamics of root remodeling and valve reimplantation; roots with supracommissural aortic replacement served as controls. METHODS: Aortic roots with aortoventricular diameter 21 mm were obtained from pigs. Root remodeling was performed using a 22-mm graft (group I, n = 6), or valve reimplantation with a 24-mm graft (group II, n = 7). Control roots were treated by supracommissural aortic replacement (22-mm graft; group III, n = 7). Using an electrohydraulic, computer-controlled pulse duplicator, the valves were tested at flows of 2, 4, 5, 7, and 9 I/min at a heart rate of 70 /min and a mean arterial pressure of 100 mmHg. Parameters assessed included: mean pressure gradient, effective orifice area, valve closure and regurgitant volume, and energy loss due to ejection, valve closure and regurgitation. Data were compared using ANOVA. RESULTS: There were no differences between the three groups in terms of regurgitant volume, energy loss due to valve regurgitation, or valve closure. The aortic valve orifice area was largest and systolic gradient lowest in group I at all flow rates (p < 0.001). Ejection energy loss was lowest in group I at all flow rates (9 l/min: group I, 128 +/- 21 mJ; group II, 399 +/- 46 mJ; group III, 312 +/- 27 mJ; p < 0.001). Valve closure volumes were similar in groups I and III, but significantly lower in group II at all flow rates (p = 0.047). CONCLUSION: In this standardized experimental setting, root remodeling--but not valve reimplantation--resulted in physiologic hemodynamic performance of the aortic valve with regard to orifice area, pressure gradient, and systolic energy loss.     

Biomarkers in acute aortic dissection and other aortic syndromes

Acute aortic syndromes have an incidence of >30 per million per annum and a high mortality without definitive treatment. Survival may relate to the speed of diagnosis. Although pain is the most common symptom, there is a large fraction of patients in whom the diagnosis may be mistaken or overlooked. Currently, a high index of clinical suspicion is the chief prompt that diverts a patient into a definitive algorithm of imaging investigations. Although there is no point-of-care biochemical test that can be reliably used to positively identify dissection, biomarkers are available that could accelerate the diagnostic pathway and thereby expedite treatment.     

Echocardiographic assessment of aortic regurgitation and aortic root dilatation in bicuspid aortic valve]

Aortic regurgitation (AR) and aortic root dilatation in 29 consecutive patients with bicuspid aortic valves but without aortic root disease (20 males, and 9 females: aged 27-85 years) were studied using two-dimensional echocardiography. The normal ranges of aortic root dimensions were calculated from values of 185 normal subjects, as 95% confidence intervals. AR was observed in 17 patients by color flow mapping. In 12 of the 17 AR patients, no significant lesion of the aortic cusp was detected by two-dimensional echocardiography. These 12 AR patients were compared with 12 patients without AR. Increase in dimension of the aortic root was relatively frequent in the 12 AR patients at the aortic annulus (AA) (67 vs 17%, p < 0.05), and at the sinus of Valsalva (A1) (67 vs 17%, p < 0.05). At the ascending aorta 5 mm distal to the sinus of Valsalva (A2), the difference was not significant (58 vs 17%, p < 0.09). The 12 bicuspid AR patients without significant lesions of the aortic cusp were compared with 41 AR patients with normal tricuspid aortic valves. The frequencies of cases with increased aortic root dimension were 67 vs 46% (ns) at the AA, 67 vs 22% (p < 0.05) at A1 and 58 vs 5% at A2 (p < 0.01). Thus, aortic annular dilatation was thought to be the cause of AR in bicuspid and tricuspid aortic valves without significant lesions of the aortic cusps, and generalized dilatation of the aortic root was more frequent in bicuspid AR patients than in tricuspid AR patients.(ABSTRACT TRUNCATED AT 250 WORDS)     

Detection and quantification of aortic regurgitation during aortic valvuloplasty

The degree of aortic regurgitation, before and after balloon aortic valvuloplasty, was assessed in 32 patients, using double indicator dilution curves: a) the forward curve was obtained by dye injection into the left ventricle and sampling in the aorta; b) the regurgitant curve was obtained by dye injection in the aorta and sampling in the left ventricle. A regurgitant index (RI) was calculated by obtaining the ratio of the areas of the triangles from regurgitant and forward curves. Eight-five percent of the patients were 70 years or older. After valvuloplasty, aortic valve area increased from 0.5 +/- 0.3 cm2 to 0.7 +/- 0.3 cm2 (P = .0002) while left ventricular to aortic gradient decreased from 77 +/- 32 to 51 +/- 24 (P = .0001). RI did not significantly change in 58% of patients, increased in 25%, and decreased in 15.2%. We conclude that in most patients undergoing aortic valvuloplasty, regurgitation does not change after the procedure. In some patients it may increase significantly, and in a few it may even decrease. Indicator dilution curves technique seems to provide a sensitive, accurate, and reproducible method to detect and quantify aortic incompetence before and after valvuloplasty.     

Single-stage treatment of aortic coarctation and aortic valve disease

Surgical management of thoracic aortic coarctation associated with severe aortic valve disease is difficult in most cases. As staged procedures are associated with a higher rate of morbidity and mortality, simultaneous operative management of both lesions is desirable. From 1997 to 2001, 9 patients (8 males and 1 female with a mean age of 30.1 +/- 10.4 years) with this condition underwent simultaneous ascending aorta-infrarenal abdominal aorta bypass graft and aortic valve replacement. One patient died from failure of the extracorporeal circulation during the operation. Another patient suffered from partial intestinal obstruction in the early postoperative period but was successfully treated. The underlying pathology was successfully corrected in the 8 surviving patients, whose blood pressure in the upper limbs was reduced while that in the lower limbs rose. Being easier to manage, the single-stage approach with extraanatomic bypass is safe and effective for managing this aortic complication.     

3例主动脉瘤及主动脉夹层合并主动脉良性肿瘤及瘤样病变的临床病理学分析

目的:发生在主动脉的良性肿瘤并伴有主动脉疾病(主动脉瘤、主动脉夹层及马方综合征)是少见病例。本文总结分析伴有主动脉疾病的主动脉良性肿瘤及瘤样病变的临床病理特点,复习发生于主动脉良性肿瘤的文献,探讨其发生与主动脉疾病之间的关系。方法:回顾性分析我院病理科2006年至2012年,手术切除的胸主动脉瘤及胸主动脉夹层的标本129例,通过复习临床病历,观察HE染色切片,辅以弹力/VG及Masson等组织化学染色及SMA、CD31及CD34等免疫组织化学染色,对主动脉壁结构的改变进行分析。结果:所有病例主动脉壁均发生了结构的改变,主要是中膜弹力纤维、平滑肌及基质的变化,但有3例标本内膜增生明显,1例形成了平滑肌瘤,另2例发生了内膜下弹力纤维瘤样增生及平滑肌瘤样增生。结论:主动脉壁内不同组成成分的改变,使得主动脉壁重构,导致主动脉瘤及主动脉夹层的形成,而某一单一成分过度增生可形成主动脉腔内的肿瘤。     

Location and severity of aortic valve calcium and implications for aortic regurgitation after transcatheter aortic valve implantation

Location of aortic valve calcium (AVC) can be better visualized on contrast-enhanced multidetector row computed tomography. The present evaluation examined whether AVC severity and its location could influence paravalvular aortic regurgitation (AR) after transcatheter aortic valve implantation. A total of 79 patients (age 80 ± 7 years, 49% men) with preprocedural multidetector row computed tomography were included. Volumetric AVC quantification and its location were assessed. Transesophageal echocardiography was performed to assess the presence and site of AR after transcatheter aortic valve implantation. Receiver operating characteristic curves were generated to evaluate the usefulness of AVC in determining paravalvular AR at a specific site. Postprocedural AR of grade 1 or more was observed in 63 patients. In most patients (n = 56, 71%), AR was of paravalvular origin. Calcium at the aortic wall of each valve cusp had the largest area under the curve (0.93, p <0.001) in predicting paravalvular AR at the aortic wall site compared to calcium at the valvular edge or body (area under the curve 0.58 and 0.67, respectively). Calcium at the valvular commissure was better than calcium at the valvular edge (area under the curve 0.94 vs 0.71) in predicting paravavular AR originating from the corresponding commissure. In conclusion, contrast-enhanced multidetector row computed tomography can be performed to quantify AVC. Both AVC severity and its exact location are important in determining paravalvular AR after transcatheter aortic valve implantation.