Standardizing the method of measuring by echocardiogram the diameter of the ascending aorta in patients with a bicuspid aortic valve

Proximal ascending aorta size is associated with the incidence of de novo aortic insufficiency with left ventricular assist device

We sought to assess the impact of the aortic root geometry on developing de novo aortic insufficiency (AI) in patients undergoing left ventricular assist device (LVAD). In total, 114 patients underwent LVAD implantation between February 2016 and January 2020 were included in this study (HeartMate3 N = 68, HeartWare N = 46). Significant aortic insufficiency was defined as mild-to-moderate or greater in echocardiography. The cohort was divided into two groups; those who developed significant AI (Group AI: n = 13) and did not (Group non-AI: n = 101). The primary outcomes of interest included late survival and predictors for significant AI. The patients in Group AI were older than Group non-AI (62.6 ± 11.9 vs 51.3 ± 14.0 years, p < 0.01). The diameter of proximal ascending aorta in Group AI was larger than Group non-AI (31.0 ± 5.0 vs 27.4 ± 4.3 mm, p < 0.01). Aortic valve remained closed in 53.8% in Group AI and 36.6% in Group non-AI (p = 0.24). The late survival was not significantly different between the groups (67.1% vs 76.0% at 3 years, log rank = 0.97). The Cox hazard model showed that larger proximal ascending aortic diameter/BSA (HR 1.55, CI 1.19-2.04, p < 0.01) and not-opening aortic valve (HR 4.73, CI 1.43-16.9, p = 0.01) were independent risk factors for significant AI. The cutoff value of proximal ascending aortic diameter/BSA was 15.5 (area under curve: 0.770, sensitivity: 0.69, specificity: 0.79). Dilated proximal ascending aorta at the time of LVAD surgery and not-opening aortic valve during follow-up were associated with the incidence of de novo significant AI.

Serial echocardiography for valve dysfunction and aortic dilation in bicuspid aortic valves

BACKGROUND AND AIMS

Complications of bicuspid aortic valve commonly include aortic stenosis, aortic regurgitation, and ascending aortic dilation. The progression of these lesions is not well described.

MATERIALS AND METHODS

We reviewed 249 bicuspid aortic valve patients with at least two echocardiograms from 2006 to 2016. Valve morphology (right-left or right-noncoronary cusp fusion) was confirmed by visual inspection, and aortic stenosis and regurgitation were quantified according to current guidelines; the ascending aorta was measured at end-systole 2-3 cm above the sinotubular junction. Annualized progression of stenosis, regurgitation, and aortic dilation from first to most recent echocardiogram were compared between right-left and right-nonfused valves using multivariable logistic regression to adjust for baseline differences in groups.

RESULTS

Among 249 bicuspid aortic valve patients (mean age 47.6 ± 13.5 years, 66.3% male), 75.9% had right-left cusp fusion. At baseline, aortic stenosis was absent or mild in 80.3%; aortic regurgitation was absent or mild in 80.7%; and aortic diameters were 35.0 ± 5.7 mm (sinuses of Valsalva) and 37.4 ± 6.2 mm (ascending). Mean annualized decrease in aortic valve area was 0.07 cm² /year, with 30% of bicuspid aortic valve patients progressing ≥0.1 cm² /year. Aortic regurgitation progressed ≥1 grade in 37 patients. Mean annualized increase in ascending aorta diameter was 0.36 mm/year in right-left and 0.65 mm/year in right-nonbicuspid valves.

CONCLUSIONS

In this serial echocardiographic study of bicuspid aortic valve patients, cusp orientation was not associated with progression of valve dysfunction. Right-noncoronary cusp fusion was associated with ascending aortic diameter progression.

Diagnostic accuracy study of routine echocardiography for bicuspid aortic valve: a retrospective study and meta-analysis

BACKGROUND

Transthoracic echocardiography (TTE) is the standard procedure to distinguish tricuspid aortic valve (TAV) from bicuspid aortic valve (BAV). Published studies assessed the accuracy of TTE for BAV under ideal conditions. Conversely, we aimed at assessing accuracy of TTE for BAV under routine conditions.

METHODS

This retrospective, cross-sectional study of 216 adults included 132 men aged 62±14 years. Of these, 108 had BAV and 108 were age-matched individuals with TAV. All diagnoses were confirmed at surgery. We assessed TTE in two patient groups. First, in the (I) group of all 216 individuals, where we assessed accuracy for BAV according to the original diagnoses as documented by the primary investigators during original TTE examination. Second, we assessed accuracy for BAV according to expert re-evaluation in (II) all 158 TTE with availability of original recordings. Third, we performed a meta-analysis of published results on the accuracy of TTE for BAV according to PRISMA standards.

RESULTS

Sensitivity, specificity and accuracy of (I) primary investigators was 46.3%, 97.2, and 71.8% as compared to (II) expert re-evaluation with 59.7%, 93%, and 77.8%, respectively. Sensitivity was significantly higher at re-evaluation (P<0.001). TTE at a non-tertiary care center (P=0.012), presence of aortic aneurysm (P=0.001) and presence of severe aortic valve calcification (P=0.003) predicted an inaccurate diagnosis of BAV. Conversely, meta-analysis of published TTE studies identified a pooled sensitivity of 87.7% and a pooled specificity of 88.3% for BAV.

CONCLUSIONS

The current study shows that TTE yields almost ideal diagnostic accuracy when ideal investigators examine ideal patients. However, the study also shows that TTE yields suboptimal diagnostic accuracy under routine conditions. TTE in non-tertiary care settings, concomitant aortic aneurysm, and presence of severe aortic valve calcification predict an inaccurate diagnosis of BAV.

Proximal thoracic aorta dimensions after continuous-flow left ventricular assist device implantation: Longitudinal changes and relation to aortic valve insufficiency

BACKGROUND

In this study we examined the impact of continuous-flow left ventricular assist device (CF-LVAD) support on proximal thoracic aorta dimensions.

METHODS

Aortic root and ascending aorta diameter were measured from serial echocardiograms before and after CF-LVAD implantation in patients with ≥6 months of support, and correlated with the development of >mild aortic valve insufficiency (AI).

RESULTS

Of 162 patients included, mean age was 58 ± 11 years and 128 (79%) were male. Seventy-nine (63%) were destination therapy patients. Mean aortic root and ascending aorta diameters at baseline, 1 month, 6 months, 12 months and long-term follow-up (mean 2.0 ± 1.4 years) were 3.5 ± 0.4, 3.5 ± 0.3, 3.9 ± 0.3, 3.9 ± 0.2 and 4.0 ± 0.3, and 3.3 ± 0.2, 3.3 ± 0.3, 3.6 ± 0.2, 3.6 ± 0.3 and 3.6 ± 0.3 cm, respectively. Only change in aortic root diameter from 1-month to 6-month follow-up reached statistical significance (p = 0.03). Nine (6%) patients had accelerated proximal thoracic aorta expansion (>0.5 cm/year), occurring predominantly in the first 6 months after implantation. These patients were older and more likely to have hypertension and baseline proximal thoracic aorta dilation. Forty-five (28%) patients developed >mild AI at long-term follow-up, including 7 of 9 (78%) of those with accelerated proximal thoracic aorta expansion. All 7 had aortic valves that remained closed throughout the cardiac cycle, and this, along with duration of CF-LVAD support and increase in aortic root diameter, were significantly associated with developing >mild AI.

CONCLUSION

CF-LVAD patients have small increases in proximal thoracic aorta dimensions that predominantly occur within the first 6 months after implantation and then stabilize. Increasing aortic root diameter was associated with AI development.

Does the aortic annulus undergo conformational change throughout the cardiac cycle? A systematic review

Accurate annular sizing in transcatheter aortic valve implantation (TAVI) planning is essential. It is now widely recognized that the annulus is an oval structure in most patients, but it remains unclear if the annulus undergoes change in size and shape during the cardiac cycle that may impact prosthesis size selection. Our aim was to assess whether the aortic annulus undergoes dynamic conformational change during the cardiac cycle and to evaluate possible implications for prosthesis size selection. We performed a systematic search in PubMed and Embase databases and reviewed all available literature on aortic annulus measurements in at least two cardiac phases. Twenty-nine articles published from 2001 to 2014 were included. In total, 2021 subjects with and without aortic stenosis were evaluated with a mean age ranging from 11 ± 3.6 to 84.9 ± 7.2 years. Two- and three-dimensional echocardiography was performed in six studies each, magnetic resonance imaging was used in one and computed tomography in 17 studies. In general, the aortic annulus was more circular in systole and predominantly oval in diastole. Whereas the annular long-axis diameter showed insignificant change throughout the cycle, the short-axis diameter, area, and perimeter were significantly larger in systole compared with diastole. Hence, the aortic annulus does undergo dynamic changes during the cardiac cycle. In patients with large conformational changes, diastolic compared with systolic measurements can result in undersizing TAVI prostheses. Due to the complex annular anatomy and dynamic change, three-dimensional assessment in multiple phases has utmost importance in TAVI planning to improve prosthesis sizing.

Predictors of ascending aortic dilation in bicuspid aortic valve disease: a five-year prospective study

BACKGROUND

Bicuspid aortic valves are associated with aortic dilation and dissection. There is a paucity of prospective studies evaluating changes in aortic size over time in adult subjects with bicuspid aortic valves.

METHODS

A total of 115 subjects with asymptomatic bicuspid aortic valves were enrolled from 2003 to 2008 and followed prospectively over 5 years. Clinical and family histories, as well as transthoracic echocardiograms, were obtained at baseline, and echocardiograms were performed annually thereafter.

RESULTS

The mean age of subjects was 41.8 ± 12.8 years, and 61% were male. Ascending aortic size at baseline averaged 35.5 ± 5.6 mm and increased in 71.1% of subjects (mean, 0.66 ± 0.05 mm/y; range, 0.2-2.3 mm/y) over an average of 4.8 years. In 15.6% of subjects, the rate of change exceeded 1 mm/y. The average rate of ascending aortic dilation for all subjects was 0.47 ± 0.05 mm/y (P < .001). A family history of aortic valve disease was associated with progression in both unadjusted (P = .029) and logistic regression analyses adjusted for age, gender, and body surface area (odds ratio, 13.7; P = .021). Multivariate analysis did not find leaflet orientation or moderate to severe aortic valve dysfunction as independent predictors of aortic dilation.

CONCLUSIONS

We found that in subjects with bicuspid aortic valve, studied prospectively, there was an annual rate of ascending aortic dilation of 0.47 mm/y. In contrast to previous reports, leaflet orientation and aortic valve dysfunction were not independent predictors of aortic dilation. A family history of aortic valve disease was associated with a significantly increased risk of increasing ascending aortic size.

Comparative measurement of aortic root by transthoracic echocardiography in normal Korean population based on two different guidelines

Background

Aortic root size is an important parameter in vascular diseases and can be easily assessed by transthoracic echocardiography. However, measurements values may vary according to cardiac cycle and the definition used for edge. This study aimed to define normal values according to the measurement method specified by two different guidelines to determine the influence of the different methods on echocardiographic measurements.

Methods

Healthy Korean adults were enrolled. The aortic root diameters were measured twice at four levels (aortic annulus, sinuses of Valsalva, sinotubular junction, and ascending aorta) by the 2005 American Society of Echocardiography (ASE) guidelines (measured from leading edge to leading edge during diastole) and the 2010 ASE pediatric guidelines (measured from inner edge to inner edge during systole).

Results

One hundred twelve subjects aged 20–69 years were enrolled. The aortic diameters (cm) determine by the aforementioned two guidelines showed significant difference. Measurements were larger in 2005 ASE guideline at aortic annuls, sinuses of Valsalva, and sinotubular junction level, but smaller at ascending aortic level with 2-3mm of differences. Intraobserver variability was similarly good, but interobserver variability was slightly higher than intraobserver variability in both measurement methods. BSA and age was most important determinant for aortic root size.

Conclusions

The measurement method of aortic root can affect the echocardiographic result. The measurement method should be noted when assessing clinical significance of aortic root measurement.

Left outflow tract anomalies in children

PURPOSE OF REVIEW

To provide a discussion of the current knowledge of the genetics of left outflow tract of the heart, including the aortic stenosis, in children. It addresses the available means of diagnosis for syndromic and nonsyndromic left outflow tract abnormalities and implications for at-risk family members. Options for prenatal testing and recommendations for cardiac follow-up are presented.

RECENT FINDINGS

Left outflow tract cardiac anomalies in children present as a varied spectrum among and within families. Even nonsyndromic forms can be inherited in an autosomal dominant pattern. These can lead to significant complications in asymptomatic individuals, making diagnosis a challenge and underscoring the importance of evaluation of at-risk family members.

SUMMARY

Improved understanding of the genetics of both syndromic and nonsyndromic left outflow tract disorders is hoped to lead to improved identification of affected children and greater ongoing cardiac follow-up for those potentially at risk.