Measurement of the ascending aorta diameter in patients with severe bicuspid and tricuspid aortic valve stenosis using dual-source computed tomography coronary angiography

Non-invasive cardiovascular magnetic resonance assessment of pressure recovery distance after aortic valve stenosis

BACKGROUND

Decisions in the management of aortic stenosis are based on the peak pressure drop, captured by Doppler echocardiography, whereas gold standard catheterization measurements assess the net pressure drop but are limited by associated risks. The relationship between these two measurements, peak and net pressure drop, is dictated by the pressure recovery along the ascending aorta which is mainly caused by turbulence energy dissipation. Currently, pressure recovery is considered to occur within the first 40-50 mm distally from the aortic valve, albeit there is inconsistency across interventionist centers on where/how to position the catheter to capture the net pressure drop.

METHODS

We developed a non-invasive method to assess the pressure recovery distance based on blood flow momentum via 4D Flow cardiovascular magnetic resonance (CMR). Multi-center acquisitions included physical flow phantoms with different stenotic valve configurations to validate this method, first against reference measurements and then against turbulent energy dissipation (respectively n = 8 and n = 28 acquisitions) and to investigate the relationship between peak and net pressure drops. Finally, we explored the potential errors of cardiac catheterisation pressure recordings as a result of neglecting the pressure recovery distance in a clinical bicuspid aortic valve (BAV) cohort of n = 32 patients.

RESULTS

In-vitro assessment of pressure recovery distance based on flow momentum achieved an average error of 1.8 ± 8.4 mm when compared to reference pressure sensors in the first phantom workbench. The momentum pressure recovery distance and the turbulent energy dissipation distance showed no statistical difference (mean difference of 2.8 ± 5.4 mm, R2 = 0.93) in the second phantom workbench. A linear correlation was observed between peak and net pressure drops, however, with strong dependences on the valvular morphology. Finally, in the BAV cohort the pressure recovery distance was 78.8 ± 34.3 mm from vena contracta, which is significantly longer than currently accepted in clinical practise (40-50 mm), and 37.5% of patients displayed a pressure recovery distance beyond the end of the ascending aorta.

CONCLUSION

The non-invasive assessment of the distance to pressure recovery is possible by tracking momentum via 4D Flow CMR. Recovery is not always complete at the ascending aorta, and catheterised recordings will overestimate the net pressure drop in those situations. There is a need to re-evaluate the methods that characterise the haemodynamic burden caused by aortic stenosis as currently clinically accepted pressure recovery distance is an underestimation.

The Presence of Ascending Aortic Dilatation in Patients Undergoing Transcatheter Aortic Valve Replacement Is Negatively Correlated with the Presence of Diabetes Mellitus and Does Not Impair Post-Procedural Outcomes

Both relevant aortic valve stenosis (AS) and aortic valve insufficiency significantly contribute to structural changes in the ascending aorta (AA) and thus to its dilatation. In patients with severe AS undergoing transcatheter aortic valve replacement (TAVR), survival data regarding aortic changes and laboratory biomarker analyses are scarce.

METHODS

A total of 179 patients with severe AS and an available computed tomography were included in this retrospective study. AA was measured, and dilatation was defined as a diameter ≥ 40 mm. Thirty-two patients had dilatation of the AA. A further 32 patients from the present population with a normal AA were matched to the aortic dilatation group with respect to gender, age, body mass index and body surface area, and the resulting study groups were compared with each other. In addition to echocardiographic and clinical characteristics, the expression of cardiovascular biomarkers such as brain natriuretic peptide (BNP), soluble suppression of tumorigenicity-2 (sST2), growth/differentiation of factor-15 (GDF-15), heart-type fatty-acid binding protein (H-FABP), insulin-like growth factor binding protein 2 (IGF-BP2) and soluble urokinase-type plasminogen activator receptor (suPAR) was analyzed. Kaplan-Meier curves for short- and long-term survival were obtained, and Pearson's and Spearman's correlations were calculated to identify the predictors between the diameter of the AA and clinical parameters.

RESULTS

A total of 19% of the total cohort had dilatation of the AA. The study group with an AA diameter ≥ 40 mm showed a significantly low comorbidity with respect to diabetes mellitus in contrast to the comparison cohort with an AA diameter < 40 mm (p = 0.010). This result continued in the correlation analyses performed, as the presence of diabetes mellitus correlated negatively not only with the diameter of the AA (r = -0.404; p = 0.001) but also with the presence of aortic dilatation (r = -0.320; p = 0.010). In addition, the presence of AA dilatation after TAVR was shown to have no differences in terms of patient survival at 1, 3 and 5 years. There were no relevant differences in the cardiovascular biomarkers studied between the patients with dilated and normal AAs.

CONCLUSION

The presence of AA dilatation before successful TAVR was not associated with a survival disadvantage at the respective follow-up intervals of 1, 3 and 5 years. Diabetes mellitus in general seemed to have a protective effect against the development of AA dilatation or aneurysm in patients with severe AS.

Short- to mid-term outcomes after transcatheter aortic valve replacement in patients with ascending aorta dilation: a single-centre retrospective analysis

OBJECTIVES

Ascending aorta dilation (AAD) is frequently associated with aortic stenosis (AS). This study investigated the procedural and clinical outcomes of transcatheter aortic valve replacement (TAVR) in patients with AAD for tricuspid AS.

METHODS

This is a single-centre retrospective study that included patients with tricuspid AS and who underwent TAVR between January 1, 2018 and December 31, 2021. A total of 239 patients met the inclusion criteria. The ascending aortic diameter was measured on computed tomography (CT) scans before TAVR, and AAD was identified as a maximal ascending aortic diameter of ≥ 40 mm. The outcomes were in line with the Valve Academy Research Consortium (VARC)-3 criteria.

RESULTS

Self-expandable (SE) valves were used in 88.7% of the total cohort (89.0% in the AAD group and 88.6% in the non-AAD group). Seventy-three patients (30.5%) were diagnosed with concomitant AAD (mean age 73.7 ± 7.3 years, 57.5% male). The median ascending aortic diameter was 36.0 mm (interquartile range [IQR]: 34.0-37.0 mm) in the non-AAD group and 44.0 mm (IQR: 42.0-46.0 mm) in the AAD group (p < 0.001). The baseline characteristics were comparable across the groups. No significant difference was observed in cumulative all-cause mortality at 30 days (2.4% vs. 1.4%, p = 0.609), 1 year (9.2% vs. 5.0%, p = 0.191), or 3 years (13.1% vs. 9.5%, p = 0.201) between the non-AAD and AAD groups. The device success rate was not different between the non-AAD and AAD groups (74.7% vs. 82.2%, p = 0.205). The multivariable analysis identified prior percutaneous coronary intervention, prior stroke, and length of intensive care unit as independent predictors of 3-year all-cause mortality among the total cohort.

CONCLUSION

AAD does not appear to be associated with the procedural and mid-term clinical outcomes in patients undergoing TAVR.

Bicuspid aortic valve annulus: assessment of geometry and size changes during the cardiac cycle as measured with a standardized method to define the annular plane

Purpose

Bicuspid aortic valve (BAV) is a complex malformation affecting not merely the aortic valve. However, little is known regarding the dynamic physiology of the aortic annulus in these patients and whether it is similar to tricuspid aortic valves (TAV). Determining the BAV annular plane is more challenging than for TAV. Our aim was to present a standardized methodology to determine BAV annulus and investigate its changes in shape and dimensions during the cardiac cycle.

Methods

BAV patients were prospectively included and underwent an ECG-gated cardiac CTA. The annulus plane was manually identified on reconstructions at 5% intervals of the cardiac cycle with a new standardized method for different BAV types. Based on semi-automatically defined contours, maximum and minimum diameter, area, area-derived diameter, perimeter, asymmetry ratio (AR), and relative area were calculated. Differences of dynamic annular parameters were assessed also per BAV type.

Results

Of the 55 patients included (38.4 ± 13.3 years; 58% males), 38 had BAV Sievers type 1, 10 type 0, and 7 type 2. The minimum diameter, perimeter, area, and area-derived diameter were significantly higher in systole than in diastole with a relative change of 13.7%, 4.8%, 13.7%, and 7.2% respectively (all p < 0.001). The AR was ≥ 1.1 in all phases, indicating an elliptic shape, with more pronounced flattening in diastole (p < 0.001). Different BAV types showed comparable dynamic changes.

Conclusions

BAV annulus undergo significant changes in shape during the cardiac cycle with a wider area in systole and a more elliptic conformation in diastole regardless of valve type.

Key Points

• A refined method for the identification of the annulus plane on CT scans of patients with bicuspid aortic valves, tailored for the specific anatomy of each valve type, is proposed.

• The annulus of patients with bicuspid aortic valves undergoes significant changes during the cardiac cycle with a wider area and more circular shape in systole regardless of valve type.

• As compared to previously published data, the bicuspid aortic valve annulus has physiological dynamics similar to that encountered in tricuspid valves but with overall larger dimensions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-021-07916-8.

Dual-Source Computed Tomography Evaluation of Children with Congenital Pulmonary Valve Stenosis

BACKGROUND

Despite dual-source computed tomography (DSCT) technology has been performed well on adults or infants with heart disease, specific knowledge about children with congenital pulmonary valve stenosis (PS) remained to be established.

OBJECTIVES

This original research aimed to establish a professional approach of DSCT performing technology on children and to assess the image quality performed by DSCT to establish a diagnostic evaluation for children with PS.

PATIENTS AND METHODS

Ninety-eight children with congenital PS referred to affiliated hospital of Jining medical college were recruited from October 2013 to March 2015. Participants were divided into four groups according to different ages (0 - 1, 1 - 3, 3 - 7, 7 - 14), or three groups according to different heart rates (< 90, 90 - 110, > 110). Image quality of pulmonary valves was assessed based on a four-point grading scale (1 - 4 points). Those cases achieving a score of ≥ 3 points were selected for further investigation, which played a critical role in our analysis. Correlation analysis was used to identify the effects of age and heart rate on image quality. Additionally, the results evaluated by DSCT were compared with those evaluated from the operation, further confirming the accuracy of DSCT.

RESULTS

Seventy-two cases (73.4%) achieved a score of ≥ 3 points based on pulmonary valve imaging, which were available for further diagnosis. There was a statistically significant difference (P < 0.05) between the four groups except 0 - 1 group and 1 - 3 group, 3 - 7 group and 7 - 14 group, and the image quality of elder group was higher than younger group. Image score was gradually decreased with increased heart rate (F = 19.05, P < 0.01). Heart rate was negatively correlated with pulmonary valve scores (r = -0.391, P < 0.001), while there was no correlation between age and scores (r = 0.185, P = 0.070). The number, shape, commissure, and opening status of pulmonary valves evaluated by DSCT were the same as the results of operation.

CONCLUSION

Heart rate serves a pivotal role in imaging quality of DSCT. DSCT provides a functional evaluation of children with congenital PS and consequently contributes to a theoretical basis for corresponding treatment protocols.

The ascending aortic aneurysm: When to intervene?

Background

Thoracic ascending aorta aneurysms (TAA) are an important cause of mortality in adults but are a relatively less studied subject compared to abdominal aortic aneurysms (AAA). The purpose of this review is to explain the main aspects (etiology, pathophysiology, diagnosis) of this disease and to summarize the most recent developments in its management.

Methodology

Literature was obtained through online health related search engines (PubMed, MEDLINE) by including the following keywords: ascending aorta aneurysm, thoracic aneurysms, Marfan syndrome, bicuspid aortic valve, familial thoracic syndrome, aortic dissection, aorta imaging and aortic aneurysm guidelines. We included articles dating from 1980 to 2014.

Findings

Literature revealed how lethal this disease can be and how simple steps such as follow-up and prophylactic surgery can significantly reduce morbidity and mortality. This review also allowed us to realize the many developments that have been made in recent years in the understanding of pathologic mechanisms of this disease.

Conclusion

TAA is a silent disease that needs to be recognized early in its course and followed closely in order to recommend appropriate preventive and prophylactic therapy in a timely manner.

Assessment of cyclic changes in the diameter of the aortic annulus using speckle-tracking trans-esophageal echocardiography

It is uncertain whether dynamic variation in the diameter of the aortic annulus occurs during the cardiac cycle in humans. The purpose of this study was to analyze cyclic changes of the aortic annulus using speckle-tracking trans-esophageal echocardiography. The subjects were 40 patients with aortic stenosis and 40 controls. Absolute and relative changes in the diameter of the aortic annulus and the times at which the maximum and minimum diameters occurred during the cardiac cycle were determined using speckle-tracking trans-esophageal echocardiography. The maximum and minimum diameters were 22.9 ± 2.7 and 20.0 ± 2.9 mm, respectively, in controls. The change in diameter of the aortic annulus was 2.9 ± 0.7 mm, and the relative change was 12.9 ± 3.5%. The maximum aortic annulus diameter was reached at the onset of aortic valve opening, and the minimum diameter occurred in the rapid filling phase. The change in diameter of the aortic annulus was significantly smaller (2.2 ± 0.6 mm vs. 2.9 ± 0.7 mm, p < 0.0001), and the time to reach the maximum diameter was significantly longer (98.5 ± 17.5 ms vs. 83.4 ± 18.2 ms, p = 0.0004), in the aortic stenosis group than in the control group. The study found that dynamic changes of the aortic annulus occur in the cardiac cycle and can be measured using speckle-tracking trans-esophageal echocardiography. We also found that aortic stenosis has an effect on the extent and timing of these changes. This suggests that accurate assessment of aortic annulus diameter requires consideration of the timing of the cardiac cycle.