Ascending aortic aneurysm and aortic valve dysfunction in bicuspid aortic valve disease

Bicuspid aortic valve-associated aortopathy: Where do we stand?

Herein we summarize the current knowledge on the bicuspid aortic valve (BAV)-associated aortopathy regarding clinical presentation and disease sub-classification, genetic background, hemodynamics, histopathology, cells and signaling, animal models, and biomarkers. Despite enormous efforts in research in all of the above areas, important issues remain unknown: (i) what is the ontogenetic basis of BAV development? (ii) how can we explain the diversity of BAV and associated aortopathy phenotypes? (iii) what are the signaling processes in aortopathy pathogenesis and how can we interfere with these processes? Despite undoubtedly great progress that has been made in the understanding of BAV-associated aortopathy, so far researchers have put together a heap of Lego bricks, but at present it is unclear if the bricks are compatible, how they fit together, and which parts are missing to build the true model of the BAV aorta. A joint approach is needed to accelerate research progress.

Age- and Sex-Related Aortic Valve Dysfunction and Aortopathy Difference in Patients with Bicuspid Aortic Valve

Bicuspid aortic valve (BAV) is the most common congenital heart disease. Different distribution of valve dysfunction was found in patients with BAV in different age and sex groups, but related difference was not well established. The aim of our study is to investigate age- and sex-related clinical characteristics differences in patients with BAV.Six hundred twenty patients with BAV who had moderate or severe aortic valve dysfunction were included in the study. Basic clinical data and image data were recorded. Patients were classified into four different age groups: (A: ≤ 50 years old; B: 50-60 years old; C: 60-70 years old; D: > 70 years old). The sex-related clinical difference in different age groups was compared. Association between incidence of aortic valve dysfunction and age was evaluated.Male patients had more frequent aortic regurgitation (AR) in patients younger than 70 years old (A: 52.3% versus 20.0%, P = 0.012; B: 43.2% versus 17.8%, P < 0.001; C: 17.0 versus 2.6%, P = 0.002), whereas female patients were more likely to have aortic stenosis (AS) (A: 75.0% versus 34.1%, P = 0.001; B: 77.8% versus 37.0%, P < 0.001; C: 93.6% versus 69.8%, P < 0.001). Frequency of AR in male patients decreased with age, whereas frequency of AS increased. Trend test showed a significant difference in incidence of aortic valve dysfunction as age increased in male patients (AR, P < 0.001; AS, P < 0.001). No trend was found in female patients.Male patients with BAV present more often with moderate/severe AR at a young age, and the frequency of AR decreases with age. Female patients with BAV had more frequent AS at first presentation regardless of age.

The bicuspid aortic valve: Is it an immunological disease process?

Bicuspid aortic valves (BAVs) are the most common congenital cardiac condition and are characterized by a structural abnormality whereby the aortic valve is composed of two leaflets instead of being trileaflet. It is linked to an increased risk for a variety of complications of the aorta, many with an immunological pathogenesis. The aim of this study is to review and analyze the literature regarding immunological processes involving BAVs, associated common pathologies, and their incidence in the population. This study will also examine current trends in surgical and therapeutic approaches to treatment and discuss the future direction of BAV treatment.

MicroRNAs as possible biomarkers for screening of aortic aneurysms: a systematic review and validation study

CONTEXT

There is an urgent need to identify non-invasive biomarkers for the early detection of aortic aneurysms, preceding a fatal event. The potential role for MicroRNAs (miRNAs) as diagnostic markers for aortic aneurysms was investigated through the present systematic review.

OBJECTIVE

To perform a comprehensive review on published studies examining the association of miRNAs with aortic aneurysms and further validate these results with plasma samples collected from thoracic aortic aneurysm (TAA) patients.

METHODS

The literature search was performed via numerous databases and articles were only included if they fulfilled the predefined eligibility criteria. The miRNAs reported three times or more with expression consistency were validated using plasma samples from TAA patients collected before and following surgery.

RESULTS

Twenty-four articles were selected from the literature search and 11 miRNAs were chosen for validation using our samples. The miRNAs which were further validated were found to follow the trend in the regulation pattern as with the majority of the published data. MiRNA hsa-miR-193a-5p was found to be significantly down-regulated in the plasma samples collected before the aneurysmal removal when compared with postsurgical serum samples.

CONCLUSIONS

Numerous miRNAs have been associated with aortic aneurysms, and specifically hsa-miR-193a-5p and hsa-miR-30b-5p; therefore they warrant further investigation as potential biomarkers. Registration: The protocol of the review was registered in Prospero Databases (ID: CRD42016039953).

Transcatheter Aortic Valve Implantation in Morphologically Complex Root Aneurysms

Performing transcatheter aortic valve implantation in the presence of aneurysmatic aortopathy is widely contraindicated but needs to be taken into account as a bailout strategy in selected patients. Deliberate preoperative assessment of measurements becomes the crucial key element in this context. After meticulous valve selection, retrograde access is obtained through the right subclavian artery additionally serving as a backup arterial cannulation site in case of conversion. Transcatheter aortic valve implantation is then performed through the transapical route. Transcatheter aortic valve implantation in complex aneurysmatic aortic morphology is feasible in highly selected patients after comprehensive preoperative evaluation. The present article describes our initial experience, safeguards, and technical details.

[Ascending aortic aneurysm: Update to existing guidelines]

The initial aorta (aortic valve, ring, sinuses and ascending aorta) constitutes an inseparable anatomical-functional entity. The "normal" diameter grows with age and body surface area. Two potential risks: aortic regurgitation (chronic complication) and aortic dissection (acute complication) The aortic diameter is the main factor of aortic dissection. Issues of the recommendations: set thresholds to indicate prophylactic surgery (avoid complication) Betablockers are indicated, especially in cases of hypertension or proven familial dystrophy.

Aortic Dissection in Patients With Bicuspid Aortic Valve-Associated Aneurysms

BACKGROUND

Data regarding the risk of aortic dissection in patients with bicuspid aortic valve and large ascending aortic diameter are limited, and appropriate timing of prophylactic ascending aortic replacement lacks consensus. Thus our objectives were to determine the risk of aortic dissection based on initial cross-sectional imaging data and clinical variables and to isolate predictors of aortic intervention in those initially prescribed serial surveillance imaging.

METHODS

From January 1995 to January 2014, 1,181 patients with bicuspid aortic valve underwent cross-sectional computed tomography (CT) or magnetic resonance imaging (MRI) to ascertain sinus or tubular ascending aortic diameter greater than or equal to 4.7 cm. Random Forest classification was used to identify risk factors for aortic dissection, and among patients undergoing surveillance, time-related analysis was used to identify risk factors for aortic intervention.

RESULTS

Prevalence of type A dissection that was detected by imaging or was found at operation or on follow-up was 5.3% (n = 63). Probability of type A dissection increased gradually at a sinus diameter of 5.0 cm--from 4.1% to 13% at 7.2 cm--and then increased steeply at an ascending aortic diameter of 5.3 cm--from 3.8% to 35% at 8.4 cm--corresponding to a cross-sectional area to height ratio of 10 cm(2)/m for sinuses of Valsalva and 13 cm(2)/m for the tubular ascending aorta. Cross-sectional area to height ratio was the best predictor of type A dissection (area under the curve [AUC] = 0.73).

CONCLUSIONS

Early prophylactic ascending aortic replacement in patients with bicuspid aortic valve should be considered at high-volume aortic centers to reduce the high risk of preventable type A dissection in those with aortas larger than approximately 5.0 cm or with a cross-sectional area to height ratio greater than approximately 10 cm(2)/m.

Fused aortic valve without an elliptical-shaped systolic orifice in patients with severe aortic stenosis: cardiac computed tomography is useful for differentiation between bicuspid aortic valve with raphe and tricuspid aortic valve with commissural fusion

OBJECTIVE

The objective is to determine cardiac computed tomography (CCT) features capable of differentiating between bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV) in severe aortic stenosis (AS) patients with fused cusp and without elliptical-shaped systolic orifices.

METHODS

We retrospectively enrolled 53 patients who had severe AS with fused cusps and without an elliptical-shaped systolic orifice on CCT and who had undergone surgery. CCT features were analyzed using: 1) aortic valve findings including cusp size, cusp area, opening shape, midline calcification, fusion length, calcium volume score, and calcium grade; 2) diameters of ascending and descending aorta, and main pulmonary artery; and 3) rheumatic mitral valve findings. The variables were evaluated using univariate and multivariate logistic regression analyses.

RESULTS

At surgery, 19 patients had BAV and 34 had TAV. CCT features including uneven cusp size, uneven cusp area, round-shaped systolic orifice, longer cusp fusion, and dilatation of ascending aorta were significantly associated with BAV (P < 0.05). In particular, fusion length (OR, 1.76; P = 0.001), uneven cusp area (OR, 10.46; P = 0.012), and midline calcification (OR, 0.08; P = 0.013) were strongly associated with BAV.

CONCLUSION

CCT provides diagnostic clues that helps differentiate between BAV with raphe and TAV with commissural fusion in patients with severe AS.

KEY POINTS

• Accurate morphologic assessment of the aortic valve is important for treatment planning. • It is difficult to differentiate BAV from TAV with a fused cusp. • CCT provides diagnostic clues for the differentiation of BAV and TAV.

Incremental prognostic value of cardiac computed tomography angiography in asymptomatic aortic stenosis: significance of aortic valve calcium score

BACKGROUND

Cardiac computed tomography angiography (CCTA) provides the simultaneous evaluation of the aortic valve, myocardium, and coronary arteries. In particular, aortic valve calcium score (AVCS) can be accurately measured on the same scanning sequence used to measure coronary artery calcification, with no additional cost or radiation exposure. We sought to evaluate the prognostic value of CCTA measures, including AVCS, in asymptomatic aortic stenosis (AS).

METHODS AND RESULTS

Sixty-four initially asymptomatic patients with AS with a normal ejection fraction were prospectively enrolled and followed for median 29 (IQR=18-50) months. During follow-up, 27 (42%) patients experienced cardiac events, including five cardiac deaths, eleven aortic valve replacements. Multivariate Cox proportional hazards analysis identified three CCTA measures as significant predictors of cardiac events: aortic valve area (per 0.1cm(2) decrease; hazard ratio [HR]: 1.19, 95% confidence interval [CI]: 1.05-1.34); multi-vessel obstructive coronary artery disease (HR: 2.84, 95% CI: 1.10-7.32); and AVCS (per 100; HR: 1.09, 95% CI: 1.04-1.15). Kaplan-Meier analysis showed that patients with AVCS greater than or equal to the median value of 723 had significantly worse outcomes than those with AVCS less than 723 (p<0.0001). The C-statistic value for cardiac events substantially increased when these CCTA measures were added to clinical characteristics plus echocardiographic peak transaortic velocity (0.913 vs. 0.702, p<0.001).

CONCLUSIONS

In patients with asymptomatic AS, CCTA measures of valve area, coronary stenosis, and calcification severity provide independent and incremental prognostic value after accounting for the echocardiographic severity of stenosis.

Hereditary patterns of bicuspid aortic valve in a hundred families

BACKGROUND

To study the following characteristics of bicuspid aortic valves (BAVs): 1) the recurrence rate in our population, 2) patterns of hereditary transmission in different BAV morphologies and 3) the aortic dimensions of BAVs in first-degree relatives (FDRs).

METHODS

A cross-sectional, prospective study of 100 consecutive families of BAV patients attending a university hospital. The following aortic valve morphologies were analysed and categorised: fusion of the right and left coronary cusps (BAV type A), right and noncoronary cusps (type B) and of the left and noncoronary cusps (type C).

RESULTS

There were 553 subjects studied, 100 cases with a BAV (46.8±15 years, 66% male, type 67% A, 32% B and 1% C; 42% with aortic dilatation), 348 FDRs (44.8% male), and 105 healthy control subjects (50% male). We detected 16 BAVs among 348 FDRs. The recurrence rates were 15% for families, 4.6% for FDRs, 7.05% in men and 2.60% in women. The morphologic concordance in family members was 68.8%. The aortic dimensions in 270 adult FDRs with a tricuspid aortic valve were significantly smaller compared with BAV patients (sinus index diameter 1.60±0.19 cm/m(2) vs. 1.82±0.29 cm/m(2), p<0.001; tubular index diameter 1.51±0.23 cm/m(2) vs. 2.00±0.45 cm/m(2), p<0.001) and similar to 103 control subjects(sinus index diameter 1.60±0.19 cm/m(2) vs. 1.59±0.17 cm/m(2), p=0.600 and tubular index diameter 1.51±0.23 cm/m(2) vs. 1.53±0.18 cm/m(2), p=0.519).

CONCLUSIONS

In our population, the BAV recurrence rate in FDRs was low (4.6%). The hereditary transmission of morphologic BAV types seems by chance, and the aortic dimensions in tricuspid FDRs are normal.

Bicuspid aortic valve disease: a comprehensive review

Bicuspid aortic valve is the commonest congenital cardiac abnormality in the general population. This paper article will discuss our current knowledge of the anatomy, pathophysiology, genetics, and clinical aspects of bicuspid aortic valve disease.