Valvular Structures Research Articles

Mechanical strain induces a pro-fibrotic phenotype in human mitral valvular interstitial cells through RhoC/ROCK/MRTF-A and Erk1/2 signaling pathways

The mitral valve is a complex multilayered structure populated by fibroblast-like cells, valvular interstitial cells (VIC) which are embedded in an extracellular matrix (ECM) scaffold and are submitted to the mechanical deformations affecting valve at each heartbeat, for an average of 40 million times per year. Myxomatous mitral valve (MMV) is the most frequent heart valve disease characterized by disruption of several valvular structures due to alterations of their ECM preventing the complete closure of the valve resulting in symptoms of prolapse and regurgitation. VIC and their ECM exhibit reciprocal dynamic processes between the mechanical signals issued from the ECM and the modulation of VIC phenotype responsible for ECM homeostasis of the valve. Abnormal perception and responsiveness of VIC to mechanical stress may induce an inappropriate adaptative remodeling of the valve progressively leading to MMV. To investigate the response of human VIC to mechanical strain and identify the molecular mechanisms of mechano-transduction in these cells, a cyclic equibiaxial elongation of 14% at the cardiac frequency of 1.16 Hz was applied to VIC by using a Flexercell-4000 T™ apparatus for increasing time (from 1 h to 8 h). We showed that cyclic stretch induces an early (1 h) and transient over-expression of TGFβ2 and αSMA. CTGF, a profibrotic growth factor promoting the synthesis of ECM components, was strongly induced after 1 and 2 h of stretching and still upregulated at 8 h. The mechanical stress-induced CTGF up-regulation was dependent on RhoC, but not RhoA, as demonstrated by siRNA-mediated silencing approaches, and further supported by evidencing RhoC activation upon cell stretching and suppression of cell response by pharmacological inhibition of the effector ROCK1/2. It was also dependent on the MEK/Erk1/2 pathway which was activated by mechanical stress independently of RhoC and ROCK. Finally, mechanical stretching induced the nuclear translocation of myocardin related transcription factor-A (MRTF-A) which forms a transcriptional complex with SRF to promote the expression of target genes, notably CTGF. Treatment of stretched cultures with inhibitors of the identified pathways (ROCK1/2, MEK/Erk1/2, MRTF-A translocation) blocked CTGF overexpression and abrogated the increased MRTF-A nuclear translocation. CTGF is up-regulated in many pathological processes involving mechanically challenged organs, promotes ECM accumulation and is considered as a hallmark of fibrotic diseases. Pharmacological targeting of MRTF-A by newly developed inhibitors may represent a relevant therapy for MMV.

Transesophageal echocardiography during endovascular aortic valve replacement (TAVI)

Objective: to evaluate the effectiveness of endovascular aortic valve replacement (TAVI) according to transesophageal echocardiography. Materials and methods: 29 TAVI operations were performed in patients with aortic valve stenosis (AV) with Lotus Valve system (Boston Scientific, USA) and CoreValve (Medtronic, USA). All patients underwent intraoperative Chpehokg on devices sh50 (Philips, the Netherlands), ACUSON SC2000 (Siemens, Germany) transesophageal sensors X7-2t, Z6Ms, at the following stages of operation: 1 - after intubation of the patient; 2 - the main stage of operation: when placing the conductor in the cavity of the left ventricle, after balloon valvuloplasty, when positioning and implantation of the prosthesis; 3 - the end of the operation. TEE at the beginning and end of the operation was conducted according to the accepted Protocol. Results: all patients had pronounced AV stenosis, peak and average pressure gradients on AV were 90.0±27.0 and 51.5±16.5 mm Hg. respectively. Intraoperative TEE in 3D mode and creating a model of the aortic root, the calculated linear dimensions of the aortic root, which coincided with the data of CT. One patient was diagnosed with worsening of the degree of mitral stenosis to expressed in the formulation of the CoreValve system, and also recorded one episode of severe pericardial effusion after placing the conductor in the cavity of the left ventricle. In all patients, hemodynamic parameters and function of prostheses after surgery were within normal limits, with an average pressure gradient on the AK prosthesis was 5.9±2.8 mm Hg. Conclusion: Tee is a basic method in the assessment of valvular structures of the heart, is of great importance for the timely diagnosis of complications during surgery endovascular aortic valve replacement, and research in 3D and 4D modes can replace the expensive research.

Stationary Blood Particle Aggregates and Vein Valve Shape: A New Classification of Vein Damage

By use of novel high-resolution ultrasound systems, valvular structures and low-flow microaggregates may be depicted today in a more detailed way. The existence of particle aggregations within a valve sinus that are neither sludge nor thrombus, detected by high-resolution ultrasound (American Venous Forum Servier Travel Award 2017), was recently reported. This consecutive study of 180 single-vein valves showing motion-resistant aggregates compares valve structures, cusp motility, and extent of aggregates, resulting in a new approach to vein damage classification. In 100 consecutive patients (68 female, 32 male; 42-64 years old) presenting with unilateral epifascial venous insufficiency, a total of 180 saphenous vein valves with motion-resistant aggregates were selected for closer high-resolution ultrasound analysis (14-16 MHz, peak up to 40 MHz; Vevo MD [SonoSite, Bothell, Wash]). Video recordings (manual three-dimensional scans) were provided for review and analysis by five experienced ultrasound investigators. Six different stages of valve changes could be determined. In stage 1, alteration of sinus hemodynamics (reduction of flushed sinus volume) was present in 102 of 180 cases (56.7%). In stage 2, restriction of cusp function due to aggregates while maintaining valve closure was seen in 64 cases (35.6%). Of 180 cases, 6 (3.3%) showed fixation of cusps (without visible motility) but yet without reflux (stage 3), whereas in 8 cases (4.5%), there was fixation of cusps causing diastolic gap and reflux (stage 4; Fig). Stages 5 and 6 were related to segments with significant reflux (>1000 ms, >10 cm/s), showing valve regression and finally loss of valve structures and aggregates. Permanent blood cell aggregates at the valve sinus seem to indicate successive stages of venous insufficiency, correlating with specific relations of sinus shape and flow. Analysis of valves and aggregates allows a new staging of vein damage and thus a more detailed determination of the individual history of disease with potential impact for early-stage treatment or prevention.

MULTISPIRAL COMPUTER TOMOGRAPHY IN DIAGNOSTICS OF PATIENTS WITH THE PATHOLOGY OF ASCENDING DEPARTMENT OF THE AORTA IN BEFORE AND POSTOPERATIVE PERIOD

This review presents current information on the diagnosis of patients with pathology of the ascending aorta in the pre and postoperative period using multispiral computed tomography. The authors paid attention to the importance of valuation of the valvular apparatus elements, the geometry of the root of the aorta (effective coaptation height, Henle triangles, aortic regurgitation area, etc.), the features of which are necessary for the surgeon to solve technical issues of the forthcoming operation. A comparison of the diagnostic value of multispiral computed tomography and transthoracic echocardiography with respect to the visualization of valvular structures is shown. The role of multispiral computed tomography in the planning of transcatheter aortic valve replacement and the determination of results after intervention is described. With the help of multispiral computed tomography, assessing the state of the ascending aorta, the aortic root and aortic valve elements, the surgeon has an opportunity to choose the optimal variant of the valve-preserving operation and to evaluate postoperative results in the preoperative period.

Comparison of Cardiac Computed Tomography With Transesophageal Echocardiography for Identifying Vegetation and Intracardiac Complications in Patients With Infective Endocarditis in the Era of 3-Dimensional Images.

Recent evolution of cardiac computed tomography (CT) provides useful information about valvular and perivalvular structures. We compared the diagnostic performance of CT and transesophageal echocardiography (TEE) with applications of 3-dimensional reconstruction in detecting vegetation and intracardiac complications in patients with infective endocarditis (IE). Seventy-five patients (53 men; age, 58±15 years) with definite IE who underwent TEE and CT with 3-dimensional reconstruction within 3 days were analyzed. The diagnostic performances of the 2 modalities for vegetation and IE-related intracardiac complications (valve perforation, valve aneurysm, perivalvular abscess, pseudoaneurysm, fistula, and prosthetic valve dehiscence) were compared. The detection rate of vegetation in TEE and CT was 97.3% and 72.0%, respectively. The maximum sizes of vegetation identified by TEE and CT were well correlated (r=0.593; P<0.001), especially in patients with large vegetation (≥10 mm), suggestive of a high risk of systemic embolism (r=0.608; P<0.001). However, small vegetation (<10 mm) was underdiagnosed by CT (52.8%) compared with TEE (94.4%), and the sizes of the 2 modalities were poorly correlated (r=0.187; P=0.445). Both modalities showed fair diagnostic performance for detecting IE-related intracardiac complications with excellent agreement. TEE was more useful for diagnosing valve perforation and intracardiac fistula, whereas CT was better for diagnosing perivalvular abscess. Cardiac CT shows a comparable diagnostic performance with TEE for large vegetation and several IE-related complications. TEE is better for detecting small vegetation, valve perforation, and intracardiac fistula, whereas CT is more useful for detecting perivalvular abscess and coronary artery disease.

PAPILLARY FIBROELASTOMA ON THE AORTIC VALVE PRESENTING AS ELECTRICAL STORM IN PATIENT WITHOUT PRIOR CARDIAC HISTORY

Papillary fibroelastomas are the most common benign neoplasm of the cardiac valvular structures. They can cause myocardial ischemia or ventricular arrhythmia as complication. 64 year old female with no prior cardiac history and no family history of sudden cardiac death who had out-of-hospital

Bileaflet pericardial patch repair for rheumatic mitral valve disease

Surgical repair in rheumatic mitral valve disease is technically challenging as the disease affects both valvular and subvalvular structures. Due to the resultant shortage of pliable valve tissue, pericardial patch techniques are progressively used to restore normal valve function. This makes mitral valve repair possible even in the most severe forms of rheumatic mitral valve disease. In this tutorial, we report a case of mitral valve repair with a bileaflet (decellularized) pericardial patch in a patient with severe rheumatic mitral valve disease.

Modelling of Lesions Associated with Functional Mitral Regurgitation in an Ex Vivo Platform.

Functional mitral regurgitation (FMR) is a complex pathology involving valvular and subvalvular structures reconfiguration, and its treatment is considered challenging. There is a lack of experimental models allowing for reliable preclinical FMR treatments' evaluation in a realistic setting. A novel approach to simulate FMR was developed and incorporated into an ex vivo passive beating heart platform. FMR was obtained by dilating the mitral annulus (MA) mainly in the antero-posterior direction and displacing the papillary muscles (PMs) apically and laterally by ad hoc designed and 3D printed dilation and displacing devices. It caused hemodynamic and valve morphology alterations. Isolated MA dilation (MAD) led to significantly increased antero-posterior distance (A-P) and decreased coaptation height (CH), tenting area (TA) and systolic leaflets angulation, resembling clinically recognized type I of mitral regurgitation with normal leaflet motion. Whereas concomitant MAD with PM displacement caused an increase in A-P, TA, CH. This geometrical configuration replicated typical determinants of type IIIb lesion with restricted leaflet motion. The proposed methods provided a realistic and repeatable ex vivo FMR model featuring two lesions clinically associated with the pathology. It bears a promise to be successfully utilized in preclinical studies, clinical training and medical education.

Fibroelastoma: a rare cause of cardioembolic stroke in the young

Objectives The investigation and management of stroke in a young person remains challenging. The majority do not have traditional risk factors and the mechanism of stroke can be unclear. We present a case of a 34-year-old East Timorese woman who had major sequential strokes caused by a cardiac fibroelastoma. We reviewed the current literature on this rare condition and its cardioembolic stroke propensity. Methods We searched PubMED/OVID databases with the term ‘fibroelastoma’. We evaluated the epidemiology, diagnosis, complications and treatment of fibroelastoma. Results Fibroelastoma is the second most common cardiac tumour arising from or attached to valvular structures.1 Autopsy series estimate an incidence of 0.33%.2 With advances and availability of cardiac imaging, these tumours are more readily detected even in the asymptomatic patient. Transoesophageal echocardiogram (TOE) and cardiac MRI have greater resolution in identifying the tumour, as a proportion are missed on transthoracic echocardiogram (TTE).3 Fibroelastoma has great thrombogenic tendency; systemic embolisation is high with stroke risk estimated at 30%–40% per annum3,4, making stroke the most frequently encountered presentation of fibroelastoma followed by arrhythmia, heart failure and sudden cardiac death. High risk tumour features are those that are (1) freely mobile, (2) greater than 1 cm and (3) located on the left side of heart.2 In symptomatic patients there is compelling evidence to support surgical excision of the tumour in a timely manner. In those asymptomatic, the data is unclear. However given the relatively safe surgical profile and detrimental consequences, it is advisable to operate. Anticoagulation is prudent while awaiting surgery. Conclusions Fibroelastoma is a rare but important cause of cardioembolic stroke. Often these tumours are missed on routine TTE. A high index of suspicion is needed and young patients with cardioembolic strokes should be considered for TOE and cardiac MRI. Treatment with surgical resection is warranted to reduce future risk of stroke.

Ultrasound Proof of Pre-Reflux Stages of Venous Insufficiency

There are several attempts to explain the origin of venous insufficiency, like hereditary or acquired modifications of receptors and transmitters by wall extension or shear stress. With use of novel high-resolution ultrasound systems (12-40 MHz), valvular structures and low-flow microaggregates may be depicted. This study examined associations between the appearance of microaggregates, changes of valve cusps, valve function, and variations of vein flow (B-flow) in patients with different patterns of vein stress. There were 33 patients (21 women, 11 men; 32-58 years), including professions with >6 hours of sitting (n = 22) or standing (n = 12), with inconspicuous findings of the great saphenous vein (GSV) during routine ultrasonography (5-10 MHz) who underwent ultrasound examination with high-resolution systems (8-16 MHz, peak up to 40 MHz). A total of 120 well-depicted GSV vein valves were selected for this study. Criteria were shape, thickness, mobility, and closure mechanism of vein valves but in particular the appearance of microaggregates and the ability of the patients to resolve these aggregates by movements, simulating their daily life. Furthermore, the effects of newly worn medical compression stockings (class II) and additional daily walking distances (+3 miles) were investigated. The higher the resolution of the chosen ultrasound mode, the more intense is the appearance of low-flow pseudoaggregates, which is the basis for B-flow mode. The definition is that pseudoaggregates are always resolvable by flow increase. True microaggregates, characterized by failing dissolution or mobilization, were found within the sinus of 47 of 120 “healthy” vein valves (39.1%). Pathologic findings were more frequent in valves of subjects with sitting or standing professions (87/96; 90.6%). Focal thickenings of valve cusps could be detected only in slim patients (depth of GSV <2.5 cm; n = 11); all of them were associated with local microaggregates. Measurements after 4 weeks with medical compression stockings or increased daily walking distances did not detect relevant changes. The observations seem to support a thesis of inflammation-induced changes of vein valves; inflammation is generated by local accumulation of blood particles. Long periods with decreased or stagnant flow, typically in individuals with lack of movement or exercise, seem to promote the formation of such aggregates. However, to eliminate microaggregates or the underlying impaired venous flow, 4 weeks of medical compression stockings or walking exercise seem to be too short. As the study is continued, updates will be presented.

Asymptomatic Cardiac Mass–Thrombosed Aneurysm of a Coronary Fistula

A 33-year-old female was noted to have a systolic murmur during anaesthetic review prior to surgery for ectopic pregnancy. Transthoracic echocardiography suggested an encapsulated immobile spherical right atrial mass suspicious of myxoma. Left ventricular systolic function and valvular structures were normal. Low dose cardiac computed tomography (CT) revealed a large (57 × 23 × 26 mm) mass in the epicardial tissue plane with focal calcification, superposterior to the right atrium, posterior to the aorta and superior vena cava, inferior to the right pulmonary artery and anterior to the left atrium. The largest calibre branch of the dilated left main was a dilated branch of the proximal circumflex which supplied the mass, suspected to be a thrombosed aneurysm of coronary-cameral fistula. This was confirmed on cardiac MRI angiography. The coronary arteries were otherwise normal. Cardiac MRI performed subsequently confirmed CT findings and further demonstrated low to intermediate signal intensity with some heterogeneity within the body of the mass with no definite fat and absence of first pass or delayed perfusion. There was no delayed enhancement. Diagnosis was changed to thrombosed aneurysm of a coronary fistula. Given increased thromboembolic risk, coronary angiography to assess drainage of the mass will be arranged. This case illustrates the incremental value of cardiac CT and cardiac MRI compared to echocardiography in identifying cardiac masses and elucidating their relationship to surrounding structures.

Application of 3D Echo in the Diagnosis of Complex CHD

Objective: to analyze the clinical value of three-dimensional echocardiography in the diagnosis of congenital heart disease by transthoracic three-dimensional echocardiography. Prospective using three-dimensional echocardiography in the diagnosis of 210 pre-operational cases of complex congenital heart disease, compared with the traditional two-dimensional ultrasound diagnosis results with surgical findings as the gold standard, the accuracy of the analysis of the characteristics and the diagnostic results of the three-dimensional ultrasound diagnosis method. Results:The diagnostic thinking of 3D echocardiography is different from that of two-dimensional echocardiography. Three dimensional thinking is more conducive to the three-dimensional understanding of the structure of the heart. For the cases of complex congenital heart disease with excellent two-dimensional image, the results of three-dimensional ultrasound diagnosis were more accurate than two-dimensional ultrasound. Including the measurement of atrial and ventricular septal defect diameter, accurate assessment of cone structure of tetralogy of Fallot patients, judge the position relationship of ventricular septal defect and large arteries of double outlet right ventricle cases. For two dimensional images with poor quality, the quality of 3D images is worse and the diagnostic results have no advantage. For congenital valvular diseases, three-dimensional ultrasound has no advantage over 2D in the diagnosis of valvular structures because of the delicate structure of valves and the resolution limits of three-dimensional images. The establishment of diagnostic thinking of three-dimensional echocardiography is beneficial to the understanding of the spatial structure of congenital heart disease and to improve the accuracy of diagnosis. The resolution of the current three-dimensional echocardiographic diagnostic instrument is still limited by the acoustic window condition, and it is still difficult to achieve satisfactory imaging for the delicate structure of the heart valve.

The Use of Standard Gastrointestinal Endoscopic Ultrasound to Assess Cardiac Anatomy.

In this prospective observational study, conducted at an academic medical center, we evaluated the feasibility of performing a basic transesophageal echocardiography (TEE) examination using endoscopic ultrasound (EUS) technology to determine what cardiac structures could be assessed. This may be potentially beneficial during hemodynamic emergencies in the endoscopy suite resulting from hypovolemia, depressed ventricular function, aortic dissection, pericardial effusions, or aortic stenosis. Of the 20 patients enrolled, 18 underwent EUS with a linear echoendoscope for standard clinical indications followed by a cardiac assessment performed under the guidance of a TEE-certified cardiac anesthesiologist. Eight of the 20 standard views of cardiovascular structures per the 1999 American Society of Echocardiography/Society of Cardiovascular Anesthesiologists guidelines for TEE could be obtained using the linear echoendoscope. The following cardiac valvular structures were visualized: aortic valve (100%), mitral valve (100%), tricuspid valve (33%), and pulmonic valve (11%). Left ventricular and right ventricular systolic function could be assessed in 89% and 67% of patients, respectively. Other structures such as the ascending and descending aorta, pericardium, left atrial appendage, and interatrial septum were identified in 100% of patients. Doppler-dependent functions could not be assessed. Given that the EUS images were not directly compared with TEE in these patients, we cannot comment definitively on the quality of these assessments and further studies would need to be performed to make a formal comparison. Based on this study, EUS technology can consistently assess the mitral valve, aortic valve, aorta, pericardium, and left ventricular function. Given its limitations, EUS technology, although not a substitute for formal echocardiography, could be a helpful early diagnostic tool in an emergency setting.

Early echocardiographic manifestations of primary chronic septic endocarditis.

Echocardiographic manifestations of the early stages of primary chronic septic endocarditis are studied in patients with mono-, bi-, and multivalvular valvulitis. The basic morphological substrate of the disease is fibrosis; the main trend is progressive fibrosis of valvular and extravalvular endocardial structures leading in many cases to stenosis of the valvular orifices. The results in some cases do not permit us to regard fibrosis as a result of previous "healed" endocarditis ruling out the presence of an inflammatory process. The basic morphological substrate of the disease corresponds to primary chronic inflammation, intrinsic to this condition. The data on the early manifestations of infectious endocarditis supplement the notions on echocardiographic manifestations this condition.

Characteristics and Outcomes for Right Heart Endocarditis: Six-year Cohort Study

Right heart endocarditis makes up 5-10% of all infective endocarditis involving valvular, congenital and artificial structures. Given the limited literature in this area, we reviewed the characteristics, management and outcomes of this condition in this retrospective cohort study. Thirty-five patients with right heart endocarditis admitted to Auckland City Hospital during 2005-2010 were followed-up for 3.4+/-2.5 years. In-hospital mortality was 11.4% (4), all occurring in those treated medically (20.0% (4) vs 0.0% (0), P=0.119). Surgical intervention was independently associated with reduced long-term mortality (HR 0.078, 95%CI 0.010-0.609, P=0.015) in multivariate analysis, while concurrent left heart endocarditis predicted both in-hospital mortality (HR 11.0, 95%CI 1.18-102, P=0.027) and long-term mortality (HR 3.20, 95%CI 1.03-9.92, P=0.044). Our study showed that surgical intervention and concomitant left heart endocarditis are positive and negative prognostic factors for outcomes after right heart endocarditis.

Aortic sclerosis and mitral annulus calcification: a window to vascular atherosclerosis?

Several similarities exist between atherosclerosis in the vasculature and chronic degenerative changes in valvular structures. It has been suggested that aortic valve sclerosis (AVS) and mitral annulus calcification (MAC) are manifestations of a generalized atherosclerosis, have similar pathogenesis, share common risk factors and are observed with higher prevalence in patients with different forms of atherosclerotic vascular disease. Moreover, recent studies have shown a close relation of MAC and AVS with adverse cardiovascular and cerebrovascular outcomes. However, many patients with AVS or MAC do not have coexisting peripheral vascular atherosclerosis and vice versa. Lipid-reducing therapy has been uniformly unsuccessful in slowing valvular calcification. Thus, whether valve calcifications are the result of a more generalized atherosclerosis, or reflect a primary degenerative process, progressing with advancing age, still remains. From a clinical point of view, it is of great importance to identify common links between valve calcification and vascular atherosclerosis with a view to assess whether the detection of AVS, MAC or both are indicative of subclinical atherosclerosis and predicts cardiovascular or cerebrovascular events. Thus, in this article, the authors review current evidence regarding the association between AVS and MAC with vascular atherosclerosis.

3D Transthoracic Echocardiography of Brucella Endoaortitis and Endocarditis of the Aortic Valve and Ascending Aorta

Mini‐AbstractEndocarditis is a rare complication of brucellosis, and it is the most common cause of deaths in brucellosis. We report a case of Brucella endocarditis and endoaortitis of the bicuspid aortic valve and ascending aorta (sinotubular junction) diagnosed with real time three‐dimensional (3D) transthoracic echocardiography. The vegetation attached to ascending aorta could be delineated with help of 3D transthoracic echocardiography suggestive of Brucella endoaortitis which is seen in fulminant infections like brucellosis. 3D echocardiography helped to understand the pathophysiology of Brucella endo‐aorto‐carditis which not only infects valvular structures but also the aortic.

Three dimensional echocardiography for quantification of valvular heart disease

In the last decade three dimensional echocardiography (3DE) technology has evolved significantly, and the advance of matrix transducers has made its use commonplace in daily clinical practice.1 Currently, it is...

Objective quantification of aortic valvular structures by cardiac computed tomography angiography in patients considered for transcatheter aortic valve implantation

To test the ability of a model-based segmentation of the aortic root for consistent assessment of aortic valve structures in patients considered for transcatheter aortic valve implantation (TAVI) who underwent 256-slice cardiac computed tomography (CT). Consecutive patients (n = 49) with symptomatic severe aortic stenosis considered for TAVI and patients without aortic stenosis (n = 17) underwent cardiac CT. Images were evaluated by two independent observers who measured the diameter of the aortic annulus and its distance to both coronary ostia (1) manually and (2) software-assisted. All acquired measures were compared with each other and to (3) fully automatic quantification. High correlations were observed for 3D measures of the aortic annulus conducted on multiple oblique planes (r = 0.87 and 0.84 between observers and model-based measures, and r = 0.81 between observers). Reproducibility was further improved by software-assisted versus manual assessment for all the acquired variables (r = 0.98 versus 0.81 for annulus diameter, r = 0.94 versus 0.85 for distance to the left coronary ostium, P < 0.01 for both). Thus, using software-assisted measurements very low limits of agreement were observed for the annulus diameter (95%CI of -1.2 to 0.6 mm) and within very low time-spent (0.6 ± 0.1 min for software-assisted versus 1.6 ± 0.3 min per patient for manual assessment, P < 0.001). Assessment of the aortic annulus using the 3D model-based instead of manual 2D-coronal measurements would have modified the implantation strategy in 12 of 49 patients (25%) with aortic stenosis. Four of 12 patients with potentially modified implantation strategy yielded postprocedural moderate paravalvular regurgitation, which may have been avoided by implantation of a larger prosthesis, as suggested by automatic 3D measures. Our study highlights the usefulness of software-assisted preprocedural assessment of the aortic annulus in patients considered for TAVI.

Erratum for a missing eComment 'Left ventricular rupture after mitral valve replacement: the most dreaded complication'

Erratum for a missing eComment to ‘Preservation versus non-preservation of mitral valve apparatus during mitral valve replacement: a meta-analysis of 3835 patients’ [Interact CardioVasc Thorac Surg 2012;15:1033–1039]† The publisher regrets having failed to include the following eComment related to the article by Sa et al. [1]. We express our sincere apologies to the author of this eComment. eComment. Left ventricular rupture after mitral valve replacement: the most dreaded complication Author: Ovidio A. Garcia-Villarreal Department of Cardiac Surgery, Hospital of Cardiovascular Disease No. 34, IMSS, Monterrey, Mexico. E-mail: moc.liamtoh@vgoidivo. doi:10.1093/icvts/ivs467 © The Author 2012. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. I have read with great interest the article by Sa et al [1]. This meta-analysis addresses a very important topic in surgery for mitral valve disease, that is, the preservation of subvalvular structures during mitral valve replacement (MVR) and its inherent consequences. As the authors note, after the analysis of 3835 patients (1918 for MVR with subvalvular preservation and 1917 for MVR with non-preservation) the odds ratio for early mortality (0.418, p <0.001), postoperative low cardiac output syndrome (0.299, p <0.001) and 5-year mortality (0.380, p <0.001) were in favour of MVR with subvalvular preservation. Unfortunately, this meta-analysis is not specific for anterior, posterior or bileaflet preservation. Many cardiac surgeons are reluctant to preserve the anterior mitral subvalvular complex due to the risk of left ventricular (LV) outflow tract obstruction. At the same time, there are no papers that conclusively prove the role of anterior subvalvular mitral structures in the concern discussed here. With regard to posterior subvalvular preservation, this is a common and easy procedure to perform in the real world. Particular care should be taken in rheumatic cases because of leaflet calcification and chordae thickening. But perhaps we have overlooked the relationship between the section of the posterior subvalvular apparatus and the LV rupture after MVR. This is a rare but dreaded and potentially lethal complication of mitral valve surgery, with an incidence of up to 1% and an associated mortality of up to 85% [2]. Treasure et al. [3] described type I and type II left ventricular ruptures as those located in the posterior atrioventricular groove, and the area overlying the papillary muscles, respectively. Type III cited by Miller et al. [4] is in an intermediate zone between the base of the papillary and the left atrioventricular sulcus, which is directly related to untethered loop hypothesis proposed by Cobbs et al. [5]. The supporting structures of the posterior LV wall form a loop. The outer portion is composed of longitudinal muscle fibres in the LV wall, and the inner portion consists of the papillary muscles with the chordae attached to the annulus of the posterior leaflet. Thus, the surgical division of the posterior leaflet chordae can seriously weaken the posterior LV wall. In rheumatic cases with advanced alteration of the valvular structures, such as chordae thickening and shortening, and leaflet thickening and calcification, preservation of the second and third order chordae tendinae of the posterior mitral leaflet may be enough to avoid this catastrophe. Conflict of interest: none declared