Sinutubular Junction Research Articles

Aortic elasticity and the influence of valve morphology in children with bicuspid aortic valve.

The study group included 44 patients and 42 controls. Patients were divided into groups according to the type of valve opening as horizontal - fusion between right and left coronary cusps - and vertical - fusion between right-non-coronary cusps; according to age they were divided into younger (5-10 years) and older patients (11-16 years). Our study did not include valve phenotype with fusion between left and non-coronary cusps. Systolic-diastolic diameters of aortic annulus, sinus valsalva, sinutubular junction, arcus, and ascending-descending and abdominal aorta were measured and z-scores were obtained. Aortic strain, distensibility, and stiffness index were calculated. Flow-mediated dilatation of brachial artery was studied. z-Scores at annulus, sinus valsalva, sinutubular junction, and ascending aorta were higher in study patients (p=0.001, p=0.0001, p=0.0001, p=0.0001, respectively). z-Scores of sinus valsalva and sinotubular junction were higher in the horizontal group than in the vertical group (p=0.006, p=0.023, respectively). z-Score was over +2 in 51% of patients with horizontal morphology and 33% of patients with vertical morphology (p=0.0001). Ascending aorta was more distensible and less stiff in the study group (11.3±5.63 versus 7.91±4.5, p=0.002; 4.76±3.60 versus 6.19±3.44 cm2.dyn-1.10-6, p=0.033, respectively). Stiffness index of ascending, arcus, and abdominal aorta were higher in the horizontal group (p=0.004, p=0.038, p=0.006, respectively). Ascending aorta was more distensible and less stiff in the younger group (p=0.007, p=0.027, respectively) but did not differ in the older group compared with the control group. Aortic dimensions are enlarged in patients with bicuspid aortic valve starting from childhood, suggesting the presence of generalised aortopathy. Aortic elasticity is increased at young age and decreased with age.

Anatomical and radiological angiographic study of the coronary ostia in the adult human hearts and their clinical significance.

This study was carried out to investigate the morphometric parameters and variations of coronary ostia in the hearts of adult human cadavers and coronary angiographs. The hearts of 60 adult human cadavers and 400 coronary angiographs were used in this study. The root of the aorta was carefully dissected to clear aortic sinuses, coronary ostia, and sinutubular junction (STJ). Number, locations, internal diameter distance between coronary ostia and their corresponding STJ, sinus bottom, and valve commissures were investigated. The anterior aortic sinus (AAS) revealed a single ostium for right coronary artery (RCA) in 77.5% of male and 80% of female hearts. This ostium gave a common origin for RCA and third coronary artery (TCA) in 15% of male and 20% of female hearts. However, two separate ostia for RCA and TCA origin were seen in 20% of male and 15% of female hearts. Moreover, three ostia were seen in one male and one female hearts within AAS. Meanwhile, the left posterior aortic sinus showed a single ostium for left coronary artery (LCA) in 97.5% of male and 95% of female hearts and two ostia in one male and one female hearts. The ostia were commonly seen below STJ and less commonly were observed above STJ. The distance between the bottom of aortic sinus and LCA ostium was longer than that of RCA. The internal diameter of RCA ostium was significantly (P<0.05) narrower than that of LCA but with no significant sex difference. Moreover, anomalous of coronary ostia was observed in seven out 400 angiographs and in two cadaveric hearts. Knowledge the morphometric parameters and anatomical variations of coronary ostia helps the cardiac surgeons to overcome the possible difficulties that could occur during surgical and radiological coronary interventions.

Invited Commentary

Invited Commentary

Location and Size of Coronary Ostia in Normal Autopsied Hearts at the University Teaching Hospital, Lusaka, Zambia

Background: Coronary ostia are orifices located in the aortic sinuses from which coronary arteries normally arise. Knowledge of their location and size is important in diagnosis and treatment cardiovascular diseases. Materials and methods: A total of 125 hearts were dissected and examined during autopsy to determine the size and location of the coronary ostia in the aortic sinus, sinu-tubular junction (STJ) or tubular part of the ascending aorta. Photographs of coronary ostia were taken and a Vernier caliper was used to measure ostia. Results: The right coronary ostium was located in the right aortic sinus 79.3% (96/121) and on the STJ in 20.7% (25/121) of the hearts. The left coronary ostium was located in the left aortic sinus in 73.6% (89/121) and on the STJ in 26.4% (32/121) of the hearts. The left coronary ostium width range was 1.6 – 7.9 mm (4.62 ± 1.104 mm) and the height range was 1.5 – 4.9 mm (2.64 ± 0.719 mm). The right coronary ostium width range was 1.6 – 9.6 mm(3.66 ± 1.40 mm) and the height range was 1.1 – 4.9 mm (2.27 ± 0.72 mm).The estimated mean cross sectional area of the left coronary ostium was 9.70 mm2 and that of the right was 6.99 mm2 . The left coronary ostium was significantly larger in size than the right with a p-value < 0.05 when their means were compared using the t-test. Conclusion: The majority of coronary ostia were located in their respective aortic sinuses below the sinutubular junction. Knowledge of the location of coronary ostia in the ascending aorta is important during angiography and surgery around the aortic root.

The clinical anatomy of high take‐off coronary arteries

A number of criteria are used in the literature to describe high take-off coronary arteries, which can in part, explain the divide in the literature on the pathological significance of this anomaly. This study presents the anatomical variations of high take-off coronary arteries to draw attention to the possible clinical implications they may cause during angiography and other surgical procedures. The English Literature was searched to review high take-off coronary arteries. A high take-off coronary artery arising at least 1 cm in adults or 20% the depth of the sinus in children above the sinutubular junction, is considered of greater clinical relevance and was included in our meta-analysis. High take-off coronaries by other criteria was also included as part of the comprehensive review. Exclusion criteria were reports made in case studies or case reviews. The prevalence of high take-off coronary arteries in our study was 26 of 12,899 (0.202%). High take-off coronary arteries were found to originate up to 5 cm above the sinutubular junction. Right coronary arteries made up 84.46% of high take-off coronary arteries reported in the literature. Three (0.023%) cases that originated more than one centimeter above the sinutubular junction was associated with sudden cardiac death. This is a higher reported association than in studies that used other criteria for classification. It is important for clinicians to recognize the importance of correctly diagnosing high take-off coronary arteries in patients with coexisting cardiac morbidities so that suitable management plans can be developed.

A geometric approach to aortic root surgical anatomy.

The aim of this study was the analysis of the geometrical relationships between the different structures constituting the aortic root, with particular attention to interleaflet triangles, haemodynamic ventriculo-arterial junction and functional aortic annulus in normal subjects. Sixteen formol-fixed human hearts with normal aortic roots were studied. The aortic root was isolated, sectioned at the midpoint of the non-coronary sinus, spread apart and photographed by a high-resolution digital camera. After calibration and picture resizing, the software AutoCAD 2004 was used to identify and measure all the elements of the interleaflets triangles and of the aortic root that were objects of our analysis. Multiple comparisons were performed with one-way analysis of variance for continuous data and with Kruskal-Wallis analysis for non-continuous data. Linear regression and Pearson's product correlation were used to correlate root element dimensions when appropriate. Student's t-test was used to compare means for unpaired data. Heron's formula was applied to estimate the functional aortic annular diameters. The non coronary-left coronary interleaflets triangles were larger, followed by inter-coronary and right-non-coronary ones. The apical angle is <60° and its standard deviation can be considered an asymmetry index. The sinu-tubular junction was shown to be 10% larger than the virtual basal ring (VBR). The mathematical relationship between the haemodynamic ventriculo-arterial junction and the VBR calculated by linear regression and expressed in terms of the diameter was: haemodynamic ventriculo-arterial junction = 2.29 VBR (diameter) + 47. Conservative aortic surgery is based on a better understanding of aortic root anatomy and physiology. The relationships among its elements are of paramount importance during aortic valve repair/sparing procedures and they can be useful also in echocardiographic analysis and in computed tomography reconstruction.

In vitro study of coronary flow occlusion in transcatheter aortic valve implantation.

Transcatheter aortic valve implantation (TAVI) has been developed recently for patients with high morbidities and who are believed to be not tolerate standard surgical aortic valve replacement. Nevertheless, the TAVI is associated with complications such as potential obstruction of coronary ostia, mitral valve insufficiency, and stent migration although it seems promising. Impairment of the coronary blood flow after TAVI is catastrophic and it was believed to be associated with the close position of the coronary orifice and the aortic leaflets and valve stent. However, few data was available as to the anatomic relationship between valve stent and aortic root anatomic structures including the coronary arterial ostia, aortic leaflets. The aortic roots were observed in 40 hearts specimens. The width of aortic leaflet, height of aortic sinus annulus to the sinutubular junction (STJ), distance between aortic sinus annulus to its corresponding coronary ostia, and coronary arterial ostia to its corresponding STJ level were measured. Moreover, the relationships of valve stent, aortic leaflets and coronary ostia before/post stent implantation and after the open of aorta were evaluated respectively. Approximate three quarters of the coronary ostia were located below the STJ level. The mean distances from left, right and posterior aortic sinus annulus to the related STJ level was comparable, which was 18.5±2.7, 18.9±2.6, 18.7±2.6 mm, respectively. Meanwhile, the height of left and right aortic sinus annulus to its corresponding coronary ostia was 16.6±2.8 and 17.2±3.1 mm for left and right side respectively. Most of the coronary ostia were located below the STJ level and could be covered by the leaflets. This highlights the need of modified stents to prevent occlusion of coronary flow after TAVI.

The anatomy and development of the cardiac valves.

Advances made in the understanding of the molecular biology of the cardiac valves have been truly spectacular. Not all of those investigating these aspects, however, have an appropriate understanding of the underlying anatomy. Partly, this reflects problems in describing the components of the various valves, a difficulty also emphasised by surgeons who repair or replace the valves. In this review, we describe briefly the overall anatomy of the cardiac valves, pointing to their similarities and differences. We then suggest that uniform terms can be developed to account for the components of the valves, treating them as complexes that guard the atrioventricular and ventriculo-arterial junctions. The atrioventricular valvar complex is made up of an annulus, leaflets, tendinous cords, and papillary muscles. The tension apparatus is required to hold the leaflets together against the force of ventricular systole. The ventriculo-arterial complex is also based on the leaflets, but supported within the valvar sinuses, and limited distally by the sinutubular junction. It is the semilunar nature of the leaflets that underscores their snug closure during ventricular diastole. The complexes thus defined can be separated to produce paired valves in the normal arrangement, or to produce common valves in the congenitally malformed hearts. Knowledge of development now permits accurate inferences to be made regarding the origin of the various components, and their relevance to valvar disease. The valvar leaflets are developed from the endocardial cushions formed in the atrioventricular canal and the outflow tract by a process of endothelial-to-mesenchymal transformation. The papillary muscles of the atrioventricular valves are then derived from the trabecular layer of the developing ventricular walls, whereas the sinuses of the ventriculo-arterial valves are formed by additional growth of the non-myocardial tissues, concomitant with excavation of the outflow cushions to form the leaflets.

Myths and Realities Relating to Development of the Arterial Valves

There is considerable confusion as to how best describe the components of the arterial valves. It is hardly surprising, therefore, that similar uncertainties apply to concepts for their development. In this review, we describe the anatomy of the arterial valves as seen in the postnatal heart. We suggest that their working components are best described as leaflets, housed in supporting arterial sinuses. The roots surrounding the leaflets, which are hinged in semilunar fashion, can then be defined as extending from a virtual ring at their base to the sinutubular junction. We also discuss the problems related to definition of the valvar “annulus”. Understanding the development of the arterial roots, which are formed in the central part of the embryonic outflow tract, is facilitated by considering the outflow tract itself as possessing three components, as opposed to the traditional “conus” and “truncus”. These three parts can be described as being distal, intermediate, and proximal. The distal part is separated to form the intrapericardial arterial trunks, while the proximal part becomes the ventricular outflow tracts. It is the intermediate component that houses the developing arterial valves, and their supporting valvar sinuses. The distal parts of the cushions that separate the outflow tract into aortic and pulmonary components, along with the intercalated cushions, excavate to form the leaflets. The walls of the sinuses are formed by growth of non-myocardial tissues from the heart-forming area. We then show how these features can be used to interpret the anatomy and development of congenitally malformed arterial valves.

Controversial areas in cardiovascular pathology

<h3>Key points</h3> 1. Anomalous coronary arteries are a cause of sudden death, usually with distribution between the great vessels. Death with exertion is common. 2. Beware normal variants of origin or distribution of coronary arteries. 3. Bridging is only diagnosed if the left anterior coronary artery is 5 mm deep and 15-20 mm long within the myocardium. 4. High take off is only diagnosed 20 mm above the sinutubular junction with narrowing of the ostium. 5. Fibromuscular dysplasia is very rare. Can be genetic or acquired. Cocaine use must be considered 6. Coronary artery dissection occurs in young pregnant or postpartum females. 7. While coronary artery spasm is an established event angio-graphically, pathologists cannot diagnose it. When there is regional infarction with normal coronary arteries it must be considered. 8. Kounis syndrome (KS) or allergic angina/myocardial infarction. Allergic acute coronary syndrome (ACS) is still questioned. Two subtypes have been described: type I, which occurs in patients without predisposing factors for coronary artery disease and is caused by coronary artery spasm, and type II, which occurs in patients with angiographic evidence of coronary disease when the allergic events induce plaque erosion or rupture. Autopsy in the context of these abnormalities means meticulous examination of the coronary arteries.

Controversial areas in cardiovascular pathology

Key points 1. Anomalous coronary arteries are a cause of sudden death, usually with distribution between the great vessels. Death with exertion is common. 2. Beware normal variants of origin or distribution of coronary arteries. 3. Bridging is only diagnosed if the left anterior coronary artery is 5 mm deep and 15-20 mm long within the myocardium. 4. High take off is only diagnosed 20 mm above the sinutubular junction with narrowing of the ostium. 5. Fibromuscular dysplasia is very rare. Can be genetic or acquired. Cocaine use must be considered. 6. Coronary artery dissection occurs in young pregnant or postpartum females. 7. While coronary artery spasm is an established event angio-graphically, pathologists cannot diagnose it. When there is regional infarction with normal coronary arteries it must be considered. 8. Kounis syndrome (KS) or allergic angina/myocardial infarction. Allergic acute coronary syndrome (ACS) is still questioned. Two subtypes have been described: type I, which occurs in patients without predisposing factors for coronary artery disease and is caused by coronary artery spasm, and type II, which occurs in patients with angiographic evidence of coronary disease when the allergic events induce plaque erosion or rupture. Autopsy in the context of these abnormalities means meticulous examination of the coronary arteries.

Sinotubular Junction Remodeling with Aortic Cusp repair. An alternative to Bentall operation for Ascending Aortic aneurysm with Aortic Valve Regurgitation.

We present a 72-year-old female patient with ascending aortic aneurysm and aortic valve regurgitation, who was referred for surgery. Preoperative echocardiography demonstrated a dilated sinutubular junction (STJ), preserved sinus dimensions and moderate to severe aortic valve insufficiency with central regurgitant jet. During surgery, comprehensive visual assessment of aortic cusp configuration revealed prolapse of the non-coronary cusp, which was repaired by appropriate techniques. Ascending aorta pathology was corrected with sinutubular junction remodelling (STJR). The combination of STJR and cusp repair is an excellent alternative to root replacement with no prosthesis-related long term complications.

The anatomy of the aortic root

The aortic root is the anatomical bridge between the left ventricle and the ascending aorta. It is made up of the aortic valve leaflets, which are supported by the aortic sinuses (of Valsalva), and the interleaflet triangles interposed between the basal attachments of the leaflets. As such, it possesses significant length, and because of the semilunar attachment of the leaflets, there is no discrete proximal border to the root. It is limited distally, nonetheless, by the supravalvar ridge, or sinutubular junction. Descriptions of the aortic root over the years have been bedeviled by accounts of a valve anulus. There are at least two rings within the root, but neither serves to support the valve leaflets, each leaflets being attached in semilunar fashion from the sinutubular junction to a basal ventricular attachment Two leaflets are supported by muscle, and the third has an exclusively fibrous attachment. The root acts as a bridging structure not only anatomically, separating the myocardial and arterial components of the left ventricular pathway, but also functionally, since its proximal and distal components can withstand considerable changes in ventricular and arterial pressures. In this review, we describe the anatomy of this crucial cardiac component, emphasizing the current problems which have arisen due to indiscriminate descriptions of a nonexistent anulus.

Is combination of aortic valve replacement with replacement of the supracoronary ascending aorta sufficient for treatment of combined aortic and valvular pathologies in case of maintained sinutubular junction?

Is combination of aortic valve replacement with replacement of the supracoronary ascending aorta sufficient for treatment of combined aortic and valvular pathologies in case of maintained sinutubular junction?

Similarities and Differences of the Aortic Root After Arterial Switch and Ross Operation in Children

Pulmonary root dilation and valve regurgitation if translocated into the aortic position is frequently seen in children with transposition of the great arteries (TGA) after an arterial switch operation, as well as in patients after the Ross procedure. Many mechanisms are thought to be responsible for the progressive dilation. Despite the differences between the 2 groups, the similarity of having the pulmonary valve and its adjacent tissue working in the systemic circulation might have a comparable effect on the neoaortic root dimensions and elasticity. We prospectively recruited 52 patients with TGA, 23 Ross patients, and 48 healthy subjects for echocardiographic assessment of their aortic valve, root, sinutubular junction, and ascending aortic dimensions and elasticity. The data were compared, stratified by patient age at investigation and the duration of follow-up postoperatively. In relation to the healthy subjects, the neoaortic root dimensions were significantly larger and the tissue stiffer and less distensible in those with TGA and those who had undergone the Ross procedure. Although the pulmonary valve of the Ross patients had been under systemic pressure load for a significantly shorter period (4.4 ± 3.6 vs 10.1 ± 5.5 years), the dimensions and elasticity values had deteriorated more. These differences could neither be clearly attributed to the age differences at surgery or to an auxiliary congenital ventricular septal defect in those with TGA or the aortic valve phenotype before the Ross operation. In conclusion, the worse outcome of the neoaortic root dimensions and elasticity in the Ross patients should at least be partly related to the different predefined pulmonary artery structures and the different development of the normal and transposed pulmonary arteries.

Intraluminal mass of the ascending aorta

A 53-year-old truck-driver, symptomatic for headache, was diagnosed [computed tomography (CT) and cardiac magnetic resonance imaging (cMRI)] with a 4 cm intraluminal aortic mass arising 3.5 cm above the sinu-tubular junction (Fig. 1A and B and Supplementary Video 1). After epiaortic ultrasound scanning (Fig. 2A and Supplementary Video 1), the ascending aorta was resected on femoral bypass, following a brief circulatory arrest before clamping. Pathology showed a thrombus on an ulcerated plaque (Fig. 2B). SUPPLEMENTARY MATERIAL

Repair of Dilated Aortic Root and Sinotubular Junction Using a Stabilizer Ring

Aortic root aneurysm and dissection are potentially life-threatening conditions that involve a structural weakness of the aortic wall. Management of aortic root aneurysm (with or without aortic insufficiency) has recently been the subject of much scholarly discussion which resulted in some modifications. The current trend is a valve-sparing root repair or replacement as well as preserving or restoring the diameter of the aortic annulus and sinutubular junction. This manuscript reviews the etiology and diagnosis of aortic root aneurysm or dilated aortic annulus as well as a novel treatment approach. A newly patented apparatus that restores and repairs the aortic annulus and sinotubular junction is reviewed.

Mid-term results after sinutubular junction remodelling with aortic cusp repair

An ascending aortic aneurysm with aortic valve regurgitation (AR) may be treated by sinutubular junction remodelling (STJR) with aortic cusp repair if the root diameter is preserved. We analysed the outcome of STJR with cusp repair. Between 1995 and 2010, 1094 patients underwent valve-preserving surgery. Of these, 560 individuals with root replacement, 128 patients with acute aortic dissection and 262 patients with preoperative AR ≤ II were excluded. The remaining 144 patients (mean age 56.0 ± 17.0 years, 103 males) underwent STJR ± cusp repair for ascending aortic aneurysm and AR ≥ III. In all, sinus dimensions were preserved according to the following criteria: maximum diameter ≤42 mm in bicuspid aortic valve (BAV, n = 59) and unicuspid aortic valve (UAV, n = 27), and ≤45 mm in tricuspid aortic valves (TAV, n = 58). In BAV, right-left (n = 52) and right-non-coronary (n = 7) cusp fusions were seen. To evaluate the influence of valve morphology, patients were divided into two groups: TAV and non-TAV. The patients with non-TAV were younger (P < 0.01) and had less concomitant cardiac surgery (P < 0.01). The mean follow-up was 25.9 ± 22.0 months. Early mortality was 2.1% (n = 3). The causes of death were cardiac (n = 1), respiratory (n = 1) and mesenteric ischaemia (n = 1). Higher age was the predictor of early mortality by multivariate analysis (P = 0.04, hazard ratio 13.2). Overall 5-year survival was 93.9 ± 2.9% (TAV, 82.8 ± 10.2%; non-TAV, 98.5 ± 1.5%; P = 0.02). Causes of late death were cardiac (n = 1), respiratory (n = 1) and carcinoma (n = 1). Freedom from recurrent AR ≥ III at 5 years was 80.1 ± 7.7% (TAV, 97.0 ± 3.0%; non-TAV, 73.4 ± 8.7%; P = 0.02). By multivariate analysis, only aortoventricular junction (AVJ) > 28 mm (P < 0.01, hazard ratio 9.7) was a predictor of recurrent AR. Freedom from reoperation at 5 years was 81.9 ± 7.8% (TAV, 97.0 ± 3.0%; non-TAV, 76.6 ± 8.8%; P < 0.05). The causes of reoperation (five re-aortic valve repairs and four valve replacements) were dehiscence of pericardial patch (n = 7) and recurrent cusp prolapse (n = 2). By multivariate analysis, only AVJ > 28 mm was a significant predictor for reoperation (P < 0.01, hazard ratio 11.6). STJR with cusp repair is a useful technique in patients with an ascending aortic aneurysm and relevant AR. Although the dilated AVJ is a risk of recurrent AR and reoperation, concomitant cusp repair is associated with an acceptable mid-term outcome.

Assessment of aortic root dimensions in patients with suspected Marfan syndrome: Intraindividual comparison of contrast-enhanced and non-contrast magnetic resonance angiography with echocardiography

PurposeOur purpose was to evaluate intraindividually the performance of contrast-enhanced magnetic resonance angiography (MRA) and non-contrast MRA for aortic root diameter measurements and to compare the results with routinely performed echocardiography in patients with suspected Marfan syndrome. Methods and materialsAortic roots were examined prospectively in 51 consecutive patients with suspected Marfan syndrome by using contrast-enhanced MRA and non-contrast MRA at 1.5T. Two readers independently measured aortic root diameters at the annulus, sinuses of Valsalva and sinutubular junction in both data sets and compared results with echocardiographic data. Intraclass correlation coefficient, Pearson correlation coefficient, Bland–Altman, and two-sided t-test were used to assess agreement between observers and methods. Results38 (74.5%) of the 51 patients (25 female, 26 male; mean age 37.1±13.7years) had Marfan syndrome. Both, contrast-enhanced MRA and non-contrast MRA measurements of the sinuses of Valsalva revealed a strong correlation with echocardiography (r=0.850 and r=0.893, respectively). Intraclass correlation was markedly better for non-enhanced MRA (r=0.904) when compared to contrast-enhanced MRA (r=0.690). Image quality (p<0.001) as well as interobserver agreement (p<0.0042) of measurements of the sinuses of Valsalva was significantly better for non-enhanced MRA than for contrast-enhanced MRA. ConclusionNon-contrast MRA was more reliable and more valid than contrast-enhanced MRA for assessment of aortic root dimensions in patients with suspected Marfan syndrome. Therefore contrast agents can be omitted for establishing the diagnosis of aortic involvement in Marfan syndrome.

Case Series of Antenatally Diagnosed Aortico-Left Ventricular Tunnel

Aortico-left ventricular tunnel (ALVT), a rare congenital anomaly was first reported in 1963 by Levy et al. [3]. It is an extracardiac channel that connects the ascending aorta above the sinutubular junction and the left ventricular cavity. There might be associated cardiac anomalies like valvular defects and abnormal coronary arteries. In the past, this anomaly was diagnosed in the postnatal period. With greater advances in fetal medicine, it is now possible to diagnose this condition antenatally.