Impact of an angulated aorto-septal relationship on cardio-cerebrovascular outcomes in patients undergoing hemodialysis

Aortic and valvular calcification are well-known risk factors for cardio-cerebrovascular events in patients undergoing hemodialysis. We investigated the clinical impact of an angulated aorto-septal angle as a result of aortic elongation due to aortic calcification on cardio-cerebrovascular outcomes in patients undergoing hemodialysis. We investigated 306 patients (mean age 65.4 years, 68% male) who underwent pre-scheduled routine echocardiography between April and September 2018. The angle between the anterior wall of the aorta and the ventricular septal surface (ASA) was quantified. We determined aortic and mitral valve calcification scores based on calcified cardiac changes; the aortic and mitral valve scores ranged between 0-9 and 0-6, respectively. The primary endpoint was a composite including cardio-cerebrovascular events and cardio-cerebrovascular death. The mean duration of dialysis among the patients in this analysis was 9.6 years. The primary endpoint was observed in 54 patients during the observational period (median 1095 days). Multivariable Cox proportional hazards analyses identified left ventricular ejection fraction (per 10% increase: hazard ratio [HR] 0.67; 95% confidential interval [CI] 0.53-0.84, P = 0.001), left ventricular mass index (per 10 g/m2 increase: HR 1.14; 95% CI 1.05-1.24, P = 0.001), ASA (per 10 degree increase: HR 0.69; 95% CI 0.54-0.88; P = 0.003), and aortic valve calcification score (HR 1.15; 95% CI 1.04-1.26, P = 0.005) as independent determinants of the primary endpoint. Kaplan-Meier analysis showed a higher incidence of the primary endpoint in patients with ASA <119.4 degrees than those with ASA ≥119.4 degrees (Log-rank P < 0.001). An angulated aorto-septal angle is an independent risk factor for cardio-cerebrovascular events and cardio-cerebrovascular death in patients undergoing hemodialysis.

Anatomical cardiac and electrocardiographic axes correlate in both upright and supine positions: an upright/supine CT study

The correlation between the anatomical cardiac and electrocardiographic axes has been discussed for several years. Using upright computed tomography, this study aimed to reveal the relationship between the anatomical cardiac and electrocardiographic axes in both the supine and upright positions. Upright CT and standard supine CT were performed for healthy volunteers, following electrocardiography in both upright and supine position. On CT images, the coordinates of apex, the center of aortic valve (AV) and mitral valve (MV) were recorded, and the vectors and angles were calculated. Subcutaneous and visceral fat volume were semi-automatically calculated in a workstation. From a total 190 volunteers, 41 males were performed electrocardiography and included for this study. The QRS and anatomical axes (AV-apex and MV-apex axis) were significantly correlated in both supine and upright positions, while the angle of the AV-apex to Z axis was the most correlated (supine: r = - 0.54, p = 0.0002, upright: r = - 0.47, p = 0.0020). The anatomical axis moved in the dorsal and caudal directions from the supine to upright position. Multiple regression analysis revealed that the anatomical axis from the AV-apex to the Z-axis was determined according to age, body height, subcutaneous and visceral fat volumes.

Diversity and determinants of the sigmoid septum and its impact on morphology of the outflow tract as revealed using cardiac computed tomography

BACKGROUND

The sigmoid septum has been generally evaluated subjectively and qualitatively, without detailed examination of its diversity, impact on the morphology of the left ventricular outflow tract (LVOT), and anatomical background.

METHODS

We enrolled 100 patients without any background cardiac diseases (67.5 ± 12.8 years old; 43% women) who underwent cardiac computed tomography. Basal septal morphology was evaluated using antero-superior and medial bulging angles (bidirectional angulation of the basal septum relative to the LVOT). The eccentricity index of the LVOT, area narrowing ratio (LVOT/virtual basal ring area), aortic-to-left ventricular axial angle (angulation of the aortic root relative to the left ventricle), and wedged height (non-coronary aortic sinus to inferior epicardium distance) were also quantified.

RESULTS

The antero-superior bulging, medial bulging, aortic-to-left ventricular axial angles, LVOT eccentricity index, area narrowing ratio, and wedged height were 76° ± 17°, 166° ± 27°, 127° ± 9°, 1.8 ± 0.5, 1.0 ± 0.2, and 41.2 ± 9.1 mm, respectively. Both bulging angles were correlated with each other and contributed to the narrowing and deformation of the LVOT. Angulated aortic root was not correlated with either bidirectional septal bulge or LVOT narrowing. Clockwise rotation of the aortic root rotation was an independent predictor of prominent antero-superior septal bulge. Deeper aortic wedging was a common independent predictor of bidirectional septal bulge.

CONCLUSIONS

The extent of septal bulge varies in normal hearts. Along with deep aortic wedging, the bidirectional bulge of the basal septum deforms and narrows the LVOT without affecting the virtual basal ring morphology.

Ascending aortic elongation and correlative change in overall configuration of the proximal aorta in elderly patients with severe aortic stenosis

BACKGROUND

Configurational changes in the proximal aorta are relevant to the procedural difficulty of transcatheter aortic valve implantation (TAVI). Among several morphological changes involving the ascending aorta, elongation is characteristics of elderly patients with aortic stenosis and can compromise the success and safety of TAVI. However, the effect of ascending aortic elongation on the overall morphology of the proximal aorta has not been established.

AIMS

Our primary purpose was to investigate the effect of ascending aortic elongation on structural changes in the proximal aorta in TAVI candidates.

MATERIALS & METHODS

In total, 121 consecutive patients with severe aortic stenosis (mean age, 84.5 ± 5.3 years; 69% women) who had undergone preprocedural computed tomography before TAVI were enrolled. We examined the structural anatomy of the proximal aorta in detail, focusing on its elongation, dilatation, tilting, rotation, and wedging.

RESULTS

The mean length of the ascending aorta was 68.0 ± 9.2 mm, and the length was significantly correlated with dilatation (R = .278, p = .002), rightward tilting (R = .437, p < .001), clockwise rotation (R = .228, p = .018), and deep wedging (R = -.366, p < .001) of the proximal aorta. Elongation of the ascending aorta was correlated with dilatation, rightward tilting, clockwise rotation, and deep wedging of the proximal aorta in an elderly population with severe aortic stenosis.

DISCUSSION

Appreciation of the clinical anatomy around the proximal aorta is required for clinicians involved in TAVI to estimate the procedural difficulty.

CONCLUSION

Elongation of the ascending aorta was associated with dilatation, rightward tilting, clockwise rotation, and deep wedging of the proximal aorta.

Association of aortic root dilatation with left ventricular function in patients with postoperative ventricular septal defect

Proximal aortic enlargement is associated with an increased risk of heart failure and all-cause mortality. Recently, aortic root dilatation (ARD) was reported in postoperative patients with ventricular septal defects (VSDs). However, the impact of ARD on left ventricular (LV) function in postoperative VSD patients remains unclear. Thus, the aim of this study was to investigate the effect of ARD on LV function in patients with postoperative VSD. One hundred and thirty-five patients (> 15 years of age) with surgically repaired isolated ventricular defects and who underwent transthoracic echocardiography in our institution between 2009 and 2013 were identified. ARD was defined as an observed aortic root diameter/body surface area > 2.1 cm/m². The propensity score estimating the probability of having ARD adjusted for anatomical and clinical characteristics was calculated. Forty-four patients (32.6%) had ARD. In unadjusted analyses, right ventricular systolic pressure, Tei index, and E/e' were significantly (p < 0.05) higher in patients with ARD than in those without ARD (31.3 ± 7.5 vs. 35.4 ± 13.7 mmHg, 0.32 ± 0.10 vs. 0.44 ± 0.15, and 7.1 ± 1.7 vs. 9.5 ± 2.9, respectively). In the propensity score-adjusted analysis, significant differences in the Tei index and E/e' were confirmed between the two groups (Tei index difference: 0.11, 95% confidence interval 0.05-0.17; E/e' difference: 2.4, 95% confidence interval 1.3-3.5). However, there were no differences in the other echocardiographic measurements. The presence of ARD in patients with postoperative VSD was significantly associated with LV diastolic dysfunction. Thus, surgically repaired VSD patients require careful screening for aortic enlargement and LV function.

Demonstration of living anatomy clarifies the morphology of interatrial communications

Inferences made regarding the postnatal anatomy of the atrial septum still tend to be based on developmental evidence. Although atrial septation is a well-defined process, it is remarkably complex and remains poorly understood. It is now established, however, that the process involves the conjugation of several myocardial structures and mesenchymal tissues of both intracardiac and extracardiac origin. The resultant postnatal morphology is equally complex, evidenced by the fact that, in the normal heart, only the floor of the oval fossa, along with its anteroinferior muscular buttress, are true anatomical septums. In this regard, septums can be defined as partitions that can be removed without creating communications with the extracavitary space. The true septal components are surrounded by grooves, which themselves largely represent infolding of the atrial walls. These anatomical features can now accurately be revealed using virtual dissection of CT data sets. These images, when carefully reconstructed, demonstrated the anatomy with as much accuracy as when hearts are dissected in the autopsy room. Such virtual dissection, furthermore, shows the components as they are seen within the chest, thus facilitating understanding for those intending to undertake interventional therapeutic procedures. By preparing such images, we show the complexity of the normal atrial septum and its surrounds. We show that it is only defects within the oval fossa, or the much rarer vestibular defects, which can appropriately be illustrated in the context of a normally constructed heart.

Elongated ascending aorta predicts a short distance between his-bundle potential recording site and coronary sinus ostium

Background

When performing catheter ablation of atrioventricular nodal reentrant tachycardia (AVNRT), it can be difficult to maintain a safe distance from the His recording site to avoid AV block in patients with a short distance between this recording site to the coronary sinus (CS) ostium (small triangle of Koch [TOK]). In this study, we sought to identify parameters predicting small TOK and test these parameters in patients undergoing AVNRT catheter ablation.

Methods

Twenty-eight patients who underwent catheter ablation of atrial fibrillation using a three-dimensional (3D) electroanatomical mapping system (EAM) with computed tomography (CT) merge (23 males; mean age, 65.8±12.1 years) were included. The shortest distance between the CS ostium and His recording sites (His-CSd) was measured on the EAM. Aortic (Ao) unfolding in chest X-ray scan, Ao angle to the LV, Ao length, Ao to the right ventricular distance, size of the Valsalva in the CT scan, and parameters of echocardiogram were evaluated. The identified parameters were subsequently tested as predictors for small TOK in patients undergoing AVNRT ablation.

Results

The size of TOK was associated with Ao length (r = −0.70, p<0.01), left ventricular end-systolic dimension (LVDs) (r = −0.51, p<0.01), and Ao unfolding. In patients with AVNRT, only Ao unfolding predicted a smaller TOK.

Conclusions

Small TOK was associated with longer Ao, larger LVDs, and Ao unfolding. Of these, Ao unfolding was associated with smaller TOK in patients with AVNRT.

The association between wedging of the aorta and cardiac structural anatomy as revealed using multidetector-row computed tomography

The aortic root is wedged within the cardiac base. The precise extent of aortic wedging, however, and its influence on the surrounding cardiac structures, has not been systematically investigated. We analysed 100 consecutive patients, who underwent coronary arterial computed tomographic angiography. We assessed the extent of aortic wedging by measuring the vertical distance between the non-adjacent aortic sinus and the inferior epicardium. A shorter distance indicates deeper aortic wedging. We assessed the tilt angle and diameter of the ascending aorta, the relative heights of the left atrial roof and the oval fossa, the shape of the proximal right coronary artery, the angle of the aorta relative to the left ventricular axis, and the lung volume. The mean extent of wedging was 42.7 ± 9.8 mm. Multivariate analysis revealed that ageing, male gender, increased body mass index, patients without cardiomyopathy, the extent of tilting and dilation of the ascending aorta, and lung volume were all independent predictors for deeper aortic wedging (R²  = 0.7400, P < 0.0001). The extent of wedging was additionally correlated with a relatively high left atrial roof (R²  = 0.1394, P < 0.0001) and oval fossa (R²  = 0.1713, P < 0.0001), the shepherd's crook shape of the proximal right coronary artery (R²  = 0.2376, P < 0.0001), and the narrowness of the angulation of the root relative to the left ventricular axis (R²  = 0.2544, P < 0.0001). In conclusion, ageing, male gender, obesity, background cardiac disease, aortic tilting and dilation, and lung volume are all correlated with the extent of wedging of the aortic root within the cardiac base.

The differences between bisecting and off-center cuts of the aortic root: The three-dimensional anatomy of the aortic root reconstructed from the living heart

BACKGROUND

It is axiomatic that the diameter of the virtual basal ring of the aortic root, which is elliptical rather than circular, will differ when assessed using between bisecting as opposed to off-center cuts. Such differences, however, which pertain directly to echocardiographic assessments of the so-called valvar annulus, have yet to be systematically explored.

METHODS

We retrospectively analyzed 30 patients undergoing coronary computed tomographic angiography, measuring the virtual basal ring diameter using routine multiplanar reconstructions. We made orthogonal bisecting cuts from the nadir of the hinge of the right coronary aortic leaflet to the center of the opposite inter-leaflet fibrous triangle between the noncoronary and left coronary aortic leaflets. We compared these measurements with orthogonal off-center cuts made through the nadirs of the hinges of the adjacent leaflets.

RESULTS

The measured diameter of the virtual basal ring was significantly longer when measured using the bisecting cut as opposed to all off-center cuts (mean difference: 1.35±1.34 mm, P<.0001; 0.77±0.95 mm, P=.0001, respectively). The measured diameters of the sinuses of Valsalva, in contrast, were significantly shorter when measured using the bisecting cut (mean difference: -3.24±1.38 mm, P<.0001; -2.86±1.61 mm, P<.0001).

CONCLUSIONS

There are significant differences in the diameters of the aortic root, which represent the echocardiographic annulus, when measured using bisecting as opposed to off-center cuts. Account should be taken of these differences when using cross-sectional echocardiographic measurements to assess the dimensions of the aortic root.