Echocardiography in transcatheter aortic (Core)Valve implantation: Part 2—Transesophageal echocardiography

Transesophageal echocardiography (TEE) plays a significant role during transcatheter aortic valve implantation (TAVR). 2DTEE allows assessment of anatomy of the aortic valve, aortic root, left ventricular (LV) outflow tract, severity of the aortic valve stenosis (AS), and the presence and severity of other valve stenosis and regurgitation. Left and right ventricular size and global function as well as cardiac hemodynamics pre and post TAVR and LV regional wall motion can be assessed. Three‐dimensional (3D) imaging adds significantly via accurate measurement of aortic annulus that helps select the appropriate valve size. Biplane imaging allows simultaneous assessment of target cardiac structure in two orthogonal views and provides a rapid assessment during and immediately post valve deployment by evaluating stent height, leaflet motion, and the presence and severity of paravalvular leak (PVL). 2DTEE and 3DTEE allow evaluation of mechanism of PVL that helps guide the decision regarding need for balloon post dilation of the implanted valve or valve in valve implantation.     

Right ventricular apical view—A new window for doppler echocardiography of aortic valve stenosis

We studied a new Doppler echocardiographic approach in 56 patients with valvular aortic stenosis from the right ventricular apex (AS-RV) and compared the transvalvular gradients with the results of the standard view from the left ventricular apex (AS-LV). AS-RV resulted in good or acceptable velocity curves in 59% of patients. The correlation between the two apical views for the peak/mean gradients were close (r = 0.95/0.96). Using all typical positions for Doppler investigation of aortic stenosis, highest peak gradients were best recorded in five cases by AS-RV. In one woman with a narrow left ventricular cavum and severe aortic stenosis, only AS-RV yielded a technically good spectral curve. Thus, in selected patients—probably those with a small left ventricular cavity or an enlarged right ventricle—AS-RV may be the best window or even the only possibility in Doppler investigation of aortic valve stenosis.     

An insight into transcatheter aortic valve implantation—a perspective from multidetector‐computed tomography

Transcatheter aortic valve implantation (TAVI) has now become an acceptable alternative to surgical aortic valve replacement for patients with severe aortic stenosis at high risk. The early enthusiasm for this technology has not diminished but rather has developed at an unprecedented rate over the last decade. Alongside the developments in implantation technique, transcatheter design, and postprocedural care, cardiac imaging modalities have also had to concurrently evolve to meet the perpetual demand for lower peri‐ and postprocedural complication rates. Although transthoracic and transesophageal echocardiography remain vital in patient's selection and periprocedural guidance, there is now emerging evidence that indicates that multidetector‐computed tomography (MDCT) may also have an equally important role to play. The aim of the current review is to examine the modern role of MDCT in assessing patients with aortic stenosis being considered for TAVI. © 2012 Wiley Periodicals, Inc.     

超声心动图在主动脉瓣狭窄经导管主动脉瓣植入术中的应用价值

目的探讨超声心动图在主动脉瓣狭窄患者经导管主动脉瓣植入术中的作用。方法3例重度主动脉瓣瓣膜狭窄患者接受经导管主动脉瓣人工瓣膜植入术。使用PhilipS iE33型彩色多普勒超声诊断仪,配备经胸探头S5—1和经食道探头S7—2,X7—2t。超声观察内容包括明确主动脉瓣膜病变范围和程度,测量主动脉瓣环前后径,人工瓣膜植入术后瓣膜功能等。结果3例患者经导管主动脉瓣植入术均取得了成功,人工瓣膜位置稳定,常规超声心动图3例患者术前经胸超声心动图与术中经食管超声心动图诊断相符,跨瓣压差较术前明显下降,主动脉瓣瓣上流速明显下降,瓣周漏瞬时反流量平均约1．2mL。结论经导管主动脉瓣人工瓣膜植入术在治疗严重主动脉瓣瓣膜狭窄中方法可行,效果良好;超声心动图在这项工作中具有重要的辅助作用。     

Noninvasive quantification of the aortic valve area in aortic stenosis by Doppler echocardiography

To develop a noninvasive approach to the quantification of thestenotic aortic valve area, Doppler echocardiography and cardiaccatheterisation were performed in 24 patients with pure aorticstenosis. The transmitral volumetric flow was measured by Dopplerechocardiography and calculated as the product of the correctedmitral orifice area (CM A) and the diastolic velocity integral(DVI). The maximal aortic jet velocities were recorded by Dopplertechnique and integrated to obtain the systolic velocity integral(SVl). Assuming that the aortic and mitral volumetric flowsare equal, the aortic valve area (A VA) was calculated as: AVA= CM A x DVI/SVI. Mean pressure gradient and cardiac outputwere measured during catheterisation and the aortic valve areawas calculated by the Gorlin formula. Comparison between theaortic valve area determined by Doppler technique and catheterisationyielded a close correlation (r = 0.92, P<0.001), and therewas no significant difference between the two measurements.Good correlations of the instantaneous pressure gradient andthe stroke volume were also obtained between the two techniques(r = 0.91 and r = 0.90, respectively, P<0.001). These resultsdemonstrate that our Doppler echocardiographic method providesa promising approach to the noninvasive quantification of theaortic valve area in aortic stenosis     

Overestimation of aortic valve gradient measured by Doppler echocardiography in patients with aortic stenosis.

We describe a series of patients with suspected aortic stenosis who were noted to have a significant aortic valve gradient by Doppler echocardiography but only a minimal gradient during cardiac catheterization. Although the pressure recovery phenomenon partially explained this discrepancy, a difference still persisted, particularly in peak gradients. The overestimation occurred at much lower cardiac catheterization gradients than previously reported. Since many of our patients were noted to be hypertensive, this discrepancy might be more apparent in this patient population.     

A unique case of “double‐orifice aortic valve”—comprehensive assessment by 2‐, 3‐dimensional,and color Doppler echocardiography

Transesophageal echocardiography (TEE) is a powerful imaging tool for the comprehensive assessment of valvular structure and function. TEE may be of added benefit when anatomy is difficult to delineate accurately by transthoracic echocardiography. In this article, we present 2‐, 3‐dimensional, and color Doppler TEE images from a male patient with aortic stenosis. A highly unusual and complex pattern of valvular calcification created a functionally “double‐orifice” valve. Such an abnormality may have implications for the accuracy of continuous‐wave Doppler echocardiography, which assumes a single orifice valve in native aortic valves.     

Impact of transcutaneous aortic valve implantation on myocardial deformation

Aims: To define the impact of transcutaneous aortic valve implantation (TAVI) using the CoreValve prosthesis on myocardial deformation in a serial echocardiographic study with analysis of strain and strain rate. Methods: In 36 patients (83 ± 6 years; EuroScore: 26 ± 13%) with severe aortic stenosis scheduled for CoreValve implantation serial echocardiographic studies pre‐ and postintervention (within 1 month) were performed. Midparasternal short‐axis and three apical views were acquired. Using customized computer software which allows automatic frame‐by‐frame tracking of acoustic markers during the heart cycle circumferential, radial, and longitudinal strain (CS, RS, and LS) and strain rate (CSR, RSR, and LSR) were calculated for each segment in a 16 segment model of the left ventricle. Results: Longitudinal strain, systolic, and early diastolic longitudinal strain rate increased significantly within 1 month after TAVI (LS from –15.8 ± 3.6% to –17.6 ± 3.1%; P < 0.001; LSR(S) from –1.03 ± 0.21 s^?1 to –1.21 ± 0.19 s^?1; P < 0.001 and LSR (E) from –1.15 ± 0.42 s^?1 to 1.51 ± 0.44 s^?1; P < 0.001). Circumferential strain and strain rate values remained unchanged after CoreValve implantation. RS (29.1 ± 17.1 to 34.0 ± 15.8%; ns), RSR (S) (1.56 ± 0.69 to 1.91 ± 0.87 s^?1; ns) and RSR(E) (–1.56 ± 0.78 to –1.81 ± 0.82 s^?1; ns) increased only nonsignificantly after TAVI. Analysis of covariance showed only chronic kidney disease to have a relevant impact on early diastolic LSR (P = 0.01). Conclusions: Mainly longitudinal mechanics respond to unloading of the left ventricle after TAVI for severe aortic stenosis while radial and circumferential deformation is substantially unchanged. Pacemaker implantation or onset of left bundle brunch block after TAVI do not influence early myocardial deformation parameters. (Echocardiography 2011;28:397‐401)     

Echocardiography in the diagnosis of thoracic aortic pathology

Transthoracic two-dimensional and Doppler echocardiography has been well established as a useful technique for evaluating many pathologic processes affecting the thoracic aorta. However, the distance of the aortic arch and descending thoracic aorta from the chest wall and the interposition of highly attenuating lung and highly reflective mediastinal structures between the transducer and the aorta present unavoidable limitations. Transesophageal echocardiography is a relatively new technology that overcomes many of the inherent limitations with transthoracic imaging. Complete echocardiographic evaluation of the entire thoracic aorta can now be achieved in nearly all patients. This article will review the continually expanding role of echocardiography in the evaluation of thoracic aortic pathology, including the dramatic impact of transesophageal imaging on the diagnosis of life-threatening disorders such as aortic dissection.     

Unicuspid aortic valve: Case series and review

A unicuspid aortic valve is a very rare valvular lesion. Its physical manifestations vary and are associated with other cardiovascular abnormalities such as aortic stenosis/insufficiency and aortopathy. Echocardiography remains the modality of choice, with computerized tomography or cardiac magnetic resonance used as adjunctive imaging. Herein, we present a case series of three patients with unicuspid aortic valves treated at our institution, with a focus on 2D and 3D echocardiographic imaging.     

Changes in mitral regurgitation after transcatheter aortic valve implantation

Objectives : To assess the acute and intermediate changes in mitral regurgitation (MR) severity after transcatheter aortic valve implantation (TAVI) with the CoreValve Revalving SystemTM (CRS). Background : Following surgical aortic valve replacement, improvement in MR is reported in 27–82% of the patients. The changes in MR severity following CRS implantation are unknown. Methods : Transthoracic echocardiography was performed in 79 consecutive patients before and after treatment, and at the first outpatient visit. Left ventricular dimensions and ejection fraction (LVEF), left atrial (LA) size, and aortic gradient were measured. MR was assessed by color flow mapping and was graded as none, mild, moderate, or severe. It was defined as organic or functional. The depth of CRS implantation was measured by angiography. Results : Post‐treatment, the mean gradient decreased from 48 ± 16 mm Hg to 9 ± 5 mm Hg (P < 0.0001). There was no significant change in the left ventricular dimensions, LA size, and LVEF. MR pretreatment was mild, moderate, or severe in 57%, 18%, and 1% of the patients, respectively. It was defined as organic in 27 patients (36%) and functional in 27 patients (36%). The degree of MR remained unchanged in 61% of the patients, improved in 17%, and worsened in 22%. MR improvement was associated with a lower baseline LVEF (P = 0.02). There was no association between the changes in MR severity and the depth of CRS implantation. Conclusions : Most patients who underwent TAVI had some degree of MR. Overall there was no change in the degree of MR post‐treatment. Patients in whom MR improved had a lower LVEF at baseline. © 2009 Wiley‐Liss, Inc.     

Assessment of aortic regurgitation by transesophageal echocardiography: correlation with angiographic determination

Transthoracic echocardiographic studies have shown that color Doppler mapping of the aortic regurgitation (AR) jet correlated well with the severity of regurgitation as assessed by contrast aortography. The present study was performed to assess whether these parameters could be similarly applied to measurements determined by transesophageal echocardiography (TEE). In order to determine and validate criteria for the assessment of AR severity, 39 clinically stable patients with a TEE color Doppler study and contrast aortography within a 2-week period were identified. The ratio of the jet area (JA) to left ventricular diastolic area (LVDA) had the best correlation to AR severity as determined by contrast aortography (r = 0.89). Jet length, JA, the ratio of jet width to the width of the left ventricular outflow tract and jet width had r values of 0.88, 0.88, 0.83, and 0.84, respectively. The best sensitivity and specificity for the assessment of AR by TEE were obtained as follows: JA/LVDA ratio of 0%-7% predicts 0-1 + AR; 8%-20% 2-3 + AR, and greater than 20% 4 + AR. Of the three patients miscategorized, none was misgraded by more than one angiographic grade of AR. Jets that measure more than 6 cm in length or have an area of greater than 10 cm 2 have a 100% sensitivity and specificity for diagnosing 4 + AR. In the present study the ratio of JA to LVDA area correlates best with AR severity as determined by angiography.     

Transcatheter aortic valve implantation for severe aortic regurgitation in a stentless bioprosthetic valve with the core valve revalving system—Technical tips and role of the accutrak system

Transcatheter aortic valve implantation may offer a less invasive alternate to surgical reoperation in patients with failed aortic bioprosthetic valves. Prior reports have focussed on successful transcatheter treatment of stented bioprosthesis. Newer stentless valves offer unique technical challenges. In the absence of radiopaque markers, the deployment is carried out under angiographic control. Device stability is also an important issue in cases of severe regurgitation. We report on the first case of percutaneous replacement of a severely regurgitant degenerated stentless bioprosthesis treated with the new iteration of the core valve system incorporating the Accutrak stability layer. Salient technical expedients have been mentioned and discussed in detail. © 2011 Wiley‐Liss, Inc.     

Acute aortic regurgitation following fibrous strand rupture of aortic valve successfully diagnosed by transesophageal echocardiography

Fibrous strand rupture is a rare cause of acute aortic regurgitation, but is a serious condition because of acute massive regurgitation. Therefore, prompt and accurate diagnosis is required. We saw a 53‐year‐old man who presented with acute dyspnea without evidence of infection. Transesophageal echocardiography revealed severe aortic regurgitation because of fibrous strand rupture. We performed surgery and found that the fibrous strand of the right coronary leaflet was ruptured. In cases of acute aortic regurgitation, the rupture of fibrous strand should be considered and transesophageal echocardiography would be very useful to diagnose it.     

Quadricuspid aortic valve: Case series and review of literature

A quadricuspid aortic valve is an uncommon valve lesion. Its physical manifestations vary, and it may be associated with other cardiac lesions. Echocardiography is the imaging modality of choice, with computerized tomography or cardiac magnetic resonance imaging being utilized as adjunctive imaging modalities in certain cases. Herein, we present a case series of three patients with this valvular lesion treated at our institution, as well as a contemporary review of the literature.     

The effect of aortic valve replacement on left ventricular mass assessed by echocardiography.

AIMS: The aim of the study was to investigate whether aortic valve replacement (AVR) has different effects on the left ventricular mass (LVM) in patients with different types of aortic valve disease, i.e. aortic stenosis (AS), aortic regurgitation (AR), or combined disease. METHODS AND RESULTS: We studied 100 patients with AS; (n=57), AR; (n=22), and combined disease; (n=21). Each patient was evaluated before and up to 8.7 years (mean follow-up period 1.42 +/- 1.65 years) after operation by transthoracic echocardiography. LVM was calculated based on echocardiographic parameters. Following AVR, the LVM for the entire group decreased from 373 +/- 145 g to 280 +/- 102 g (P=0.0001). The AS subgroup lost 13.7 +/- 30.7% from the preoperative LVM, compared to 28.8 +/- 24.8% in the AR subgroup (P<0.05) and 23.1 +/- 33.1% in the combined subgroup. The preoperative LVM was higher among patients with AR vs. AS patients (501 +/- 173 g vs. 319 +/- 100 g respectively, P<0.05). The decrease in LVM was significantly higher in patients with preoperative AR compared to AS patients (165 +/- 150 g vs. 58 +/- 96 g, respectively, P<0.05). However, the postoperative LVM remained higher among the former. The only preoperative parameter (of the LVM formula) that was different between AR and AS patients was the left ventricular end diastolic diameter (68 +/- 11 mm vs. 51 +/- 7 mm, respectively, P<0.05). No significant differences were found in wall thickness among the groups studied. Univariate analysis showed that gender (male), type of aortic valve disease (AR vs. AS), and larger prosthetic valve diameter correlated significantly with greater decrease in postoperative LVM. In multivariate analysis comparing the above variables between AS and AR subgroups, only the patient's gender (i.e. male) was identified as an independent predictor of LVM regression. CONCLUSION: Patients with AR have a greater decline in LVM compared with patients with AS following AVR. The postoperative decline in LVM is higher among males and those with larger prosthetic valve diameter.