Evolution of Native Aortic Valve Function following Ascending Aorta Replacement for Acute Type A Dissection

Abstract

Background

This study investigates the evolution of aortic valve function following supracoronary ascending aorta replacement (SCR) for acute type A aortic dissection (ATAAD). Factors contributing to aortic valve stability and progression of aortic valve insufficiency (AI) were examined.

Methods

Patients who survived SCR for ATAAD between 2000 and 2021 were included. Univariable analyses to identify risk factors for AI grade ≥ 2 were performed, including anatomical parameters, perioperative findings, and follow-up root diameters. Evolution of aortic root dimensions was also investigated.

Results

Seventy-eight patients were included. AI grade ≥ 2 was observed in 20 (29.4%) patients during follow-up. Cumulative incidence of AI grade ≥ 2 was 4.7 ± 2.2%, 7.9 ± 3.4%, and 15.1 ± 5.5% at 1, 5, and 10 years, respectively. Aortic root reoperation was performed in three patients (4.0%) within 3 years of the index operation. Significant predictors of AI grade ≥ 2 included preoperative AI grade ≥2 (p = 0.037, odds ratio [OR] 1.46, 95% confidence interval [CI]: 1.02–2.09) and significant preoperative AI grade ≥ 2 in presence of at least two dissected sinuses (p = 0.039, OR: 2.88, 95% CI: 1.05–7.89). Diameters of the sinus of Valsalva (p < 0.001), sinotubular junction (p < 0.001), and ascending aorta graft (p < 0.001) increased over time. Absence of sinus of Valsalva ≥ 45 mm was 90.9, 84.9, and 80.3% at 1, 5, and 10 years, respectively.

Conclusion

Preserving the aortic valve after ATAAD offers a viable long-term surgical option with a low need for proximal root reoperations in patients without aortic root dilatation. Significant preoperative AI, particularly in presence of extensive root dissection, are significant predictors of late AI grade ≥ 2, suggesting valve-sparing root replacement in these patients.

 

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Keywords

dissection - aortic valve - insufficiency - supracoronary

Introduction

Acute Type A aortic dissection (ATAAD) continues to exhibit a high mortality rate despite advancements in perioperative management, surgical techniques, and postoperative care protocols.[1] [2] A tear-oriented intervention usually involves replacing the ascending aorta with or without aortic arch and root treatment.[1] [2] [3] Investigations have indicated that aortic root and valve preservation may lead to the development of progressive aortic valve insufficiency (AI) and root dilatation, entailing an increased need for reoperation.[1] [4] [5] [6] Conversely, certain studies found that a more comprehensive strategy, such as valve-sparing root replacement, reduces the late risk of developing significant AI without a concomitant rise in perioperative mortality.[1] [3] [5] [7] [8] The optimal therapeutic approach for ATAAD therefore remains a matter of debate.[1] [8] Limited research has focused on identifying predictive risk factors of progressive AI, root dilatation, and need for proximal reoperation.[1] This study aims to assess the determinants influencing the stability of the aortic valve/root and the progression of AI in the context of surgery for ATAAD treated by supracoronary ascending aorta replacement SCR .

 

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Materials and Methods

This study was approved by the Ethical Committee of the University Hospital of Ghent (BC-11312). Because of the retrospective nature of the study, the need for individual patient consent was waived. All consecutive patients undergoing surgical ascending aorta replacement for ATAAD in the University Hospital Ghent, from January 2000 to December 2021, were considered. Exclusion criteria were concomitant aortic valve and/or root replacement, valve-sparing root replacement, a history of prior surgery on the aortic valve or aortic root, and patients with iatrogenic dissection. Patients who died at the time of the index operation were excluded.

Data Collection

Patient characteristics, preoperative, operative, and postoperative data, encompassing both early and late outcomes, were systematically gathered from the electronic hospital database. Operative details and anatomical presentations were derived from the operative report. Follow-up information was extracted from regular outpatient clinic visit reports. Echocardiography was employed to evaluate aortic valve function, whereas electrocardiography-gated computed tomography was utilized to acquire aortic root dimensions during end-diastole in the coronal plane. The diameter of the ascending aorta or ascending aorta graft was measured at the mid-ascending aorta level, specifically at the point of the pulmonary artery bifurcation. Similarly, the aortic root diameter was assessed at the largest level of the sinus of Valsalva (SoV) from cusp to commissure. Measurements of the sinotubular junction (STJ) diameter were performed just distally to the coronary arteries. The diameter of the aortic annulus was measured from cusp nadir to cusp nadir at the level of the annulus.

 

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Surgical Strategy

All surgical procedures were promptly conducted upon confirmation of the diagnosis, via median sternotomy and with extracorporeal circulation, deep hypothermic circulatory arrest, and with selective antegrade cerebral perfusion. Transesophageal echocardiography was systematically used to evaluate aortic valve function and aortic root anatomy. The cannulation strategy was determined on an individual basis, according to the preferences of the operating surgeon and the anatomical presentation. The aortic arch lumen was always explored for residual tears. The surgical approach encompassed supracoronary replacement with open distal anastomosis only in patients exhibiting normal aortic root diameters, no intimal tear in the aortic root/arch, and no known connective tissue disorders.[2] Identification of a tear within the aortic arch prompted subsequent total arch or hemiarch replacement. Dissected aortic root tissue was excised at the level of the STJ. If deemed necessary, BioGlue (BioGlue Surgical Adhesive, Cryolife Inc., Kennesaw, GA) or Teflon felt was introduced between the layers of the dissected aortic wall at the level of the aortic root.

 

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Statistical Analysis

The statistical analysis of the database parameters was conducted using IBM SPSS software (Statistics version 27.0, IBM, Armonk, NY). Continuous variables are presented as mean ± standard deviation or median (interquartile range), whenever appropriate. Categorical variables are expressed as counts and percentages.

Normality is assessed for all continuous variables through a histogram, Q–Q plot and the Shapiro–Wilk normality test. Comparison of discharge and follow-up aortic dimensions is conducted using repeated measures analysis of variance. Univariate Cox regression analysis was conducted to identify risk factors for development of AI grade ≥ 2. The size effect of these risk factors was quantified using odds ratios (OR) with 95% confidence intervals (CI). Survival is determined using the Kaplan–Meier survival method, with time expressed in years. Significance in the survival analysis was deemed applicable within a follow-up period of at least 10 years, with the criterium ensuring the sustained inclusion of a minimum of 10% of the population at risk. A competing risk analysis was performed to analyze the development of AI grade ≥ 2 and need for aortic root reoperation, using death as competing event. Both endpoints were then presented by the cumulative incidence function. A two-sided p-value < 0.05 is considered statistically significant.

 

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Results

General Characteristics

In total, 152 patients underwent surgery for ATAAD during the study period. During the index hospitalization, 34 patients (22.4%) died. Thirty patients underwent composite root replacement (Bentall procedure), in 88 patients the aortic valve was preserved, 10 of whom had a valve-sparing root replacement (David procedure). Finally, 78 patients underwent only supracoronary ascending aortic replacement and were eligible for the study. [Fig. 1] displays a flowchart of the patient selection. [Table 1] provides an overview of patient characteristics. Bicuspid aortic valve was intraoperatively identified in three (3.9%) patients. Arterial hypertension (94.8%), dyslipidemia (59.2%), and active smoking (42.1%) were the most prevalent comorbidities. Two (2.6%) patients had previously undergone distal aortic surgery. Malperfusion was observed in 37 patients, of which limb malperfusion occurred most frequently (n = 18, 23.1%). Fifty-six (73.7%) patients presented with DeBakey class I, 20 (26.3%) with DeBakey class II ATAAD.

Fig. 1 Patient selection flowchart. The blue colored box displays the study population.

Table 1 Patient characteristics

Variable	Study population
	(n = 78)
General characteristics
Gender
Male	51 (65.4%)
Female	27 (34.6%)
Age at surgery (y)	62.4 ± 11.8
Weight (kg)	79.4 ± 16.9
Length (cm)	171.4 ± 8.8
BMI (kg/m2)	26.4 ± 3.9
Genetic mutations
Marfan's disease	0 (0.0%)
Aortic valve morphology
Bicuspid aortic valve	3 (3.9%)
Tricuspid aortic valve	74 (96.1%)
Comorbidities
Arterial hypertension	73 (94.8%)
Dyslipidemia	45 (59.2%)
Diabetes mellitus Type 2	8 (10.4%)
Currently smoking	32 (42.1%)
eGFR < 60 mL/min/1.73 m2	11 (14.3%)
Chronic obstructive pulmonary disease	9 (11.7%)
Peripheral artery disease	8 (10.5%)
Coronary artery disease	8 (10.5%)
Experienced transient ischemic accident prior to surgery	2 (2.6%)
Experienced cerebrovascular accident prior to surgery	3 (3.9%)
Experienced acute myocardial infarction prior to surgery	1 (1.3%)
Previous interventions
Previous aortic procedure	2 (2.6%)
Previous percutaneous coronary intervention	2 (2.6%)
Previous coronary artery bypass grafting	2 (2.6%)
Preoperative heart rate
Sinus rhythm	72 (92.3%)
Atrial fibrillation	5 (6.4%)
Pacemaker	1 (1.3%)
Preoperative clinical presentation
Main symptom at presentation
Acute chest pain	52 (67.5%)
Cardiogenic shock	12 (15.6%)
Dyspnea	1 (1.3%)
Malperfusion	12 (15.6%)
Mesenterial malperfusion	4 (5.1%)
Limb malperfusion	18 (23.1%)
Cerebral malperfusion	9 (11.5%)
Coronary malperfusion	8 (10.3%)
Preoperative diagnostic parameters
DeBakey classification
Type I	56 (73.7%)
Type II	20 (26.3%)
Preoperative aortic valve insufficiency (AI) degree
0/4	22 (30.6%)
01/4	22 (30.6%)
02/4	17 (23.6%)
03/4	8 (11.1%)
04/4	3 (4.2%)
Preoperative left ventricular ejection fraction
Good	65 (90.3%)
Moderate	5 (6.9%)
Bad	2 (2.8%)
Preoperative pericardial effusion	37 (48.1%)
Preoperative SoV diameter (mm)[a]	38.5 ± 5.3
Preoperative STJ diameter (mm)[a]	37.5 ± 6.9
Preoperative annulus diameter (mm)[a]	25.7 ± 2.7
Preoperative ascending aorta diameter (mm)[a]	47.6 ± 9.3
Preoperative STJ/SoV ratio	0.97 ± 0.12

Abbreviations: BMI, body mass index; eGFR, estimated glomerular filtration rate; IQR, interquartile range; SD, standard deviation; SoV, sinus of Valsalva; STJ, sinotubular junction.

Note: Values are expressed as mean ± SD, median (IQR), or numbers (n) with percentage.

^a SoV, STJ, annulus, and ascendens diameters were measured with computed tomography imaging in coronal plane.

[Table 2] provides an overview of all surgical parameters. Root reinforcement with BioGlue and/or Teflon felt between the dissected layers was performed in 53 (69.7%) and 6 (7.9%) patients, respectively. The primary intimal tear was intraoperatively confirmed in the ascending aorta in 48 (62.3%) patients. At the aortic root, the dissection most commonly extended into the noncoronary sinus (n = 39, 63.9%), followed by the right and left coronary sinus in 21 (34.4%) and 13 (21.7%) patients, respectively. Fifty (65.8%) patients underwent additional arch replacement, of which 31 (39.7%) had hemiarch, and 19 (24.4%) total-arch replacement. Three (3.9%) patients underwent leaflet repair of the aortic valve.

Table 2 Surgical parameters

Variable, n (%)	Study population
(Mean ± SD)	(n = 78)
Preoperative anatomical findings
Localization of intimal tear
Aortic root	5 (6.5%)
Aorta ascendens	48 (62.3%)
Aortic arch	22 (28.6%)
Distal aorta	2 (2.6%)
Number of dissected sinuses
0	19 (31.1%)
1	20 (32.8%)
2	12 (19.7%)
3	10 (16.4%)
Dissection of right coronary sinus	21 (34.4%)
Dissection of left coronary sinus	13 (21.7%)
Dissection of noncoronary sinus	39 (63.9%)
Dissection of left coronary artery	1 (1.6%)
Dissection of right coronary artery	4 (6.2%)
Treatment
Cardiopulmonary bypass time (min)	158 (133–175)
Cross clamp time (min)	75 (60–96)
BioGlue in the aortic root	53 (69.7%)
Teflon felt in the aortic root	6 (7.9%)
Aortic valve leaflet repair
Leaflet repair	3 (3.9%)
Hemiarch replacement	31 (39.7%)
Total arch replacement	19 (24.4%)
Concomitant cardiac surgery
Coronary artery bypass grafting	3 (3.8%)

Abbreviations: IQR, interquartile range; SD, standard deviation.

Note: Values are expressed as mean ± SD, median (IQR), or numbers (n) with percentage.

The early outcomes are presented in [Table 3]. The median duration of intensive care unit stay was 6.0 days (5.0–12.0). The median total hospital length of stay was 16.5 days (12.0–27.0). Revision for bleeding was required in 14 (18.2%) patients. Neurological symptoms (cerebrovascular accident, epilepsy, swallowing difficulties, and paresthesia) were experienced by 16 (20.8%) patients in the perioperative period and observed in 15 (19.5%) patients at discharge. Acute renal insufficiency emerged as the most prevalent postoperative complication, occurring in 40 (51.9%) patients.

Table 3 Early and late outcomes

Variable, n (%)	Study population
(Mean ± SD)	(n = 78)
Early outcomes
Postoperative complications
Revision for bleeding	14 (18.2%)
Dialysis	6 (7.8%)
Acute renal failure	40 (51.9%)
Perioperative transient neurological symptoms	16 (20.8%)
Persistent neurological symptoms	15 (19.5%)
Prolonged ventilation (>48 u)	22 (28.6%)
Pneumonia	32 (41.6%)
Mediastinitis	1 (1.3%)
Multiorgan failure	7 (9.1%)
Sepsis	9 (11.7%)
Superficial wound infection	4 (5.2%)
Pulmonary embolism	3 (3.9%)
Length of stay
Length of intensive care unit stay (d)	6.0 (5.0–12.0)
Length of hospital stay (d)	16.5 (12.0–27.0)
Echo- and CT parameters at discharge
Postoperative AI degree
0/4	36 (50.7%)
01/4	31 (43.7%)
02/4	3 (4.2%)
03/4	1 (1.4%)
Postoperative left ventricular ejection fraction
Good	58 (81.7%)
Moderate	13 (18.3%)
SoV diameter at discharge (mm)[a]	37.5 ± 4.5
STJ diameter at discharge (mm)[a]	31.1 ± 3.2
Annulus diameter at discharge (mm)[a]	25.7 ± 2.1
Ascendens graft diameter at discharge (mm)[a]	30.7 ± 2.8
STJ/SoV ratio at discharge	0.83 ± 0.08
Rhythm at discharge
Heart rate at discharge
Sinus rhythm	45 (58.4%)
Atrial fibrillation	30 (39.0%)
AV block	1 (1.3%)
Pacemaker	1 (1.3%)
Late outcomes
Follow-up time (y)	4.5 (1.1–9.1)
Mortality
Mortality	23 (29.5%)
Cause of death
Unknown	15 (65.2%)
Cardiac	4 (17.4%)
Noncardiac	4 (17.4%)
Time until death (y)	7.4 (1.7–9.6)
Evolution of AI
AI ≥ 2 at latest follow-up	20 (29.4%)
Reoperations
Proximal reoperation	3 (4.0%)
Due to AI	2 (66.7%)
Due to root aneurysm	1 (33.3%)
Due to pseudoaneurysm	0 (0%)
Time until proximal reoperation (y)	1.6 ± 1.0
Reoperation on the distal aorta	9 (12.2%)

Abbreviations: AI, aortic valve insufficiency; AV, atrioventricular; CT, computed tomography; IQR, interquartile range; SD, standard deviation; SoV, sinus of Valsalva; STJ, sinotubular junction.

Notes: Values are expressed as mean ± SD, median (IQR), or numbers (n) with percentage.

^a SoV, STJ, annulus, and ascendens diameters were measured with CT imaging in coronal plane.

The median follow-up time was 4.5 (1.1–9.1) years; follow-up was 97.4% complete. Data pertaining to late outcomes are presented in [Table 3]. AI grade ≥ 2 was identified in 20 (29.5%) patients at last follow-up. Three (4.0%) patients were reoperated on the aortic root and valve, whereas 9 (12.2%) patients underwent an aortic arch and/or more distal aorta reoperation.

Survival at 1, 5, and 10 years was 93.5 ± 2.9, 90.9 ± 3.8, and 75.3 ± 8.0%, respectively. Beyond 13 years, only 11.7% of the study population remained available for follow-up ([Fig. 2]).

Fig. 2 Kaplan–Meier survival curve of the study population. The number of patients at risk at a specific time point is indicated by a numeral above the corresponding year.

 

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Aortic Valve Function during Follow-up

During follow-up, 20 patients (29.4%) developed AI grade ≥ 2 on average 2.6 ± 3.1 years after the index operation. Among these 20 patients, SoV dilatation ≥ 45 mm was observed in 7 (35.0%) patients. [Table 4] illustrates risk factors for development of AI grade ≥ 2. Significant predictors of AI grade ≥ 2 included preoperative AI (57.9 vs. 30.4% in AI < 2; p = 0.037, OR: 1.46, 95% CI: 1.02–2.09) and concomitant preoperative AI grade ≥ 2 with dissection of two or more sinuses (43.8 vs. 8.1% in AI < 2; p = 0.039, OR: 2.88, 95% CI: 1.05–7.89). Dissection of two or more sinuses tended to be predictive (OR: 2.33, 95% CI: 0.89–6.35, p = 0.076) but was statistically not significant. Dissection of the right coronary sinus (64.7 vs. 24.3%, p = 0.084) and root reinforcement with BioGlue (90.0 vs. 58.7%, p = 0.113) were also more commonly observed in patients developing AI grade ≥ 2. Similarly, the incidence of a SoV ≥ 45 mm was higher in patients developing AI grade ≥ 2 (36.8 vs. 15.2% in AI < 2) but was also not statistically significant. The cumulative incidence of late AI grade ≥ 2, considering death as a competing risk, is illustrated in [Fig. 3]. Cumulative incidence of AI grade ≥ 2 was 4.7 ± 2.2, 7.9 ± 3.4, and 15.1 ± 5.5% at 1, 5, and 10 years, respectively.

Table 4 Risk factors for the development of aortic valve insufficiency grade ≥ 2 during follow-up

Risk factor	Odds ratio	95% CI	p-Value
Arterial hypertension	0.37	0.11–1.29	0.12
Preop AI ≥ 2	1.46	1.02–2.09	0.037
Preop SoV diameter (mm)[a]	0.94	0.82–1.07	0.305
Preop STJ diameter (mm)[a]	1	0.93–1.09	0.937
Preop annulus diameter (mm)[a]	0.93	0.76–1.15	0.509
Preop Asc diameter (mm)[a]	1.03	0.97–1.1	0.289
Preop STJ/SoV ratio	24.85	0.26–2414.30	0.169
Dissection of 2 or more sinuses	2.33	0.86–6.35	0.098
Preop AI ≥ 2 and dissection of 2 or more sinuses	2.88	1.05–7.89	0.039
RCS dissection	2.43	0.89–6.65	0.084
LCS dissection	1.09	0.37–3.19	0.879
NCS dissection	1.73	0.56–5.31	0.34
LCA dissection	0.05	0.00–54314.74	0.669
RCA dissection	1.16	0.26–5.01	0.847
BioGlue in aortic root	3.29	0.76–14.28	0.113
Felt in aortic root	0.04	0.00–433.44	0.505
Aortic valve leaflet repair	0.65	0.09–4.87	0.673
AI at discharge
01/4	1.51	0.55–4.20	0.427
02/4	80.37	11.92–542.06	<0.001
03/4	272.35	11.91–6227.17	<0.001
Development of SoV ≥ 45	1.76	0.69–4.53	0.239
Mortality	1.98	0.75–5.18	0.166

Abbreviations: AI, aortic valve insufficiency; Asc, ascending aorta; CI, confidence interval; CT, computed tomography; LCA, left coronary artery; LCS, left coronary sinus; NCS, noncoronary sinus; preop, preoperative; RCA, right coronary artery; RCS, right coronary sinus; SoV, sinus of Valsalva; STJ, sinotubular junction.

^a SoV, STJ, annulus, and ascendens diameters were measured with CT imaging in coronal plane.

Fig. 3 Cumulative incidence of late AI grade ≥ 2, considering death as a competing risk. The number of patients at risk at a specific time point is indicated within the graph.

 

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Reoperations on the Aortic Valve and Root

In total, three patients (4.0%) underwent a reoperation on the proximal aorta, on average 1.6 ± 1.0 years after the initial surgery. The cumulative incidence of proximal reoperation, considering death as a competing risk is illustrated in [Fig. 4]. Cumulative incidence of proximal reoperation was 1.6 ± 1.6 and 3.8 ± 2.7% at 1 and 5 years, respectively. One patient (1.3%) underwent a reoperation due to a SoV aneurysm, and two patients (2.7%) underwent aortic valve replacement for increasing AI with symptoms and/or signs of left ventricular volume overload within 3 years after the index operation. No patient developed a pseudoaneurysm requiring reoperation during the study period.

Fig. 4 Cumulative incidence of aortic root reoperation, considering death as a competing risk. The number of patients at risk at a specific time point is indicated within the graph.

 

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Evolution of the Aortic Root and Ascending Aorta Dimensions during Follow-up

Preoperative, postoperative, and follow-up imaging of the proximal aorta was available for 49 (62.8%), 58 (74.4%), and 63 (80.8%) patients, respectively. The mean SoV diameter preoperatively, postoperatively, and at the latest follow-up was 38.5 ± 5.3, 37.5 ± 4.5, and 39.0 ± 5.3 mm (p < 0.001), respectively. For the mean STJ diameter, the values were 37.5 ± 6.9, 31.1 ± 3.2, and 33.0 ± 4.0 (p < 0.001) mm. The mean aortic annulus diameter measured 25.7 ± 2.7, 25.7 ± 2.1, and 26.1 ± 2.2 (p = 0.113) mm. As for the ascending aorta and ascending aorta graft, the respective measurements were 47.6 ± 9.3, 30.7 ± 2.8, and 32.0 ± 2.8 (p < 0.001) mm. Fifteen (22.7%) patients developed a SoV ≥ 45 mm. The absence of a SoV ≥ 45 mm at 1, 5, and 10 years was 90.9, 84.9, and 80.3%, respectively.

 

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Discussion

The optimal surgical strategy concerning the aortic root in ATAAD remains controversial.[1] [8] [9] The main objectives of surgical repair of the aortic root at the time of acute aortic dissection are to eliminate or reapproximate sinus dissection, to prevent aortic root bleeding/rupture, and to avoid the development of aortic valve incompetence and sinus pseudoaneurysm.[10] Potential techniques to preserve the native aortic valve function in the setting of aortic root dissection include commissural resuspension, reapproximation of the dissected layers with tissue felt or BioGlue, or to decide for a root replacement procedure according to the reimplantation or remodeling technique.[1] [2] [4] This decision must be individually assessed per patient, weighing the balance between keeping the patient alive by shortening the procedure versus maximizing the durability of repair to improve the long-term outcome.[6] [8] [11] [12] This study demonstrates that SCR is a safe technique with a reliable effect on the evolution of aortic valve function and aortic root dilation in the midterm. If the aortic valve exhibits significant preoperative regurgitation, especially when accompanied by extensive dissection of the aortic root affecting at least two sinuses, a more aggressive aortic root procedure (either valve-sparing root replacement or Bentall procedure) is necessary to prevent the occurrence of significant AI. The use of BioGlue or felt to reinforce the dissected aortic root, however, is insufficient to resolve this issue.

Preoperative Aortic Valve Function and Anatomical Presentation

The occurrence of AI as a complication of ATAAD is estimated to vary between 40 and 60%.[13] In this study, even a higher incidence was observed, with 69% of patients displaying some degree of AI at presentation. Ro et al[9] found no correlation between the severity of preoperative AI and preoperative SoV diameter but did show a correlation with the diameter of the annulus and STJ. The mean preoperative SoV diameter in this study was only 38mm, justifying the policy to perform a root replacement procedure in larger aortic roots, particularly with diameters >45 mm, or in patients with connective tissue disorders, as suggested by others.[8] [14]

 

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Evolution of Aortic Root Dimensions

Studies have demonstrated substantial hemodynamic alterations occurring at the level of the aortic root following ascending aorta replacement. The inherent rigidity of the adjacent vascular prosthesis leads to an elevation in parietal tension along the wall of the aortic root.[8] [15] Several authors have shown a significant increase in the diameter of SoV after surgery.[2] [8] [15] Our investigation also revealed a significant growth of the aortic root size over time at the level of the SoV (p < 0.001) and STJ (p < 0.001). Ro et al[9] reported an incidence of 9.7% in the development of a SoV ≥ 45 mm, within a shorter median follow-up of 45 months, while in our study population, this incidence was 22.7%. Similar outcomes were reported by Ro et al[9] and Bojko et al,[16] where these two outcomes occurred simultaneously in 40 and 26%, respectively.

 

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Evolution of Aortic Valve Function and Risk Factors for Development of Aortic Valve Insufficiency Grade ≥ 2 during Follow-up

Higher preoperative and postoperative AI grades have been demonstrated by Kim et al[1] to be predictors of developing severe AI later. Additionally, Pessotto et al[13] and Bojko et al[16] identified preoperative AI grade as the sole predictor for late-onset AI, with a 5-year absence of AI grade ≥ 2 at 92 versus 76% in patients presenting with preoperative AI grades < 2 and ≥2, respectively. In contrast to the aforementioned authors, Molteni et al[12] could not establish a correlation between preoperative AI grade and the development of late-onset AI.[12] A systematic review and meta-analysis of root-sparing procedures for ATAAD calculated a linearized rate for recurrent AI grade ≥ 2 at 1.12%/patient-years.[10] In our study, this was calculated at 4.50%/patient-years. Our results also indicated a correlation between higher preoperative AI grade and the development of later AI grade ≥2, but we also demonstrated that a nicely repaired aortic valve with no to trivial AI at discharge had a low risk for developing severe late AI. While BioGlue is known to help with tissue reinforcement of the dissected aortic wall layers in ATAAD, research by Molteni et al[12] identified its role as a risk factor promoting late-onset AI. Interestingly, they also demonstrated that late-onset AI grade could not be associated with intrinsic diameters of the aortic root, indicating that the mechanism of late-onset AI is not solely caused by aortic root dilation. Our study also showed a higher incidence of late-onset AI grade ≥ 2 after root reinforcement after use of BioGlue. This effect is probably not solely attributable to the use of BioGlue but might be seen as a surrogate for more severe damage to the aortic root.[12]

A notable observation is the greater association between right coronary sinus dissection among patients who developed AI grade ≥ 2, as well as with root dissection involving two or more sinuses. Our study shows that patients with a preoperative AI grade ≥ 2 face a significantly increased risk of developing late AI grade ≥ 2. Furthermore, the concomitant occurrence of dissection affecting two or more sinuses amplifies this risk. Conversely, we can assert that a low preoperative AI grade at the index operation and limited aortic root damage were associated with a significantly lower likelihood of developing significant AI. These findings support the statement that patients presenting with severe AI at first presentation, are at increased risk for developing severe late AI, especially when two or more sinuses of the aortic root are involved. In this condition, performing a root replacement at the index operation is recommended to avoid the risk of aortic valve function deterioration and eventual need for root reoperation. Several authors have demonstrated that the David valve-sparing procedure can be performed in acute situations with good long-term results and similar survival as aortic root-sparing surgery.[3] [11] [17] [18] A lower incidence of late AI grade ≥ 2 was reported after valve-sparing root replacement compared with a root-sparing approach.[5] [18] [19] In addition, the observations from this study may also have implications for the follow-up of patients. Particularly, patients exhibiting moderate AI at discharge are strongly advised to undergo close echocardiographic follow-up for comprehensive monitoring.

 

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Reoperations on the Proximal Aorta

The incidence of proximal reoperations varies significantly among studies. The incidence of late proximal reoperations after SCR ranges from 3.0 to 9.0% after 5 years and 8.0 to 23.2% after 10 years.[8] [17] [20] [21] [22] [23] A possible explanation for this variability is that the indication for reoperation is not only based on echocardiographic data but also take the clinical condition, comorbidities, and the surgeon's experience into account.[4] In our study population, only three reoperations were performed, resulting in a low cumulative incidence of root reoperation of 1.6 ± 1.6 and 3.8 ± 2.7% at 1 and 5 years, respectively. Two patients underwent reoperation due to increasing AI with symptoms and/or signs of left ventricular volume overload and one patient due to an aortic root aneurysm. Despite the frequent occurrence of pseudoaneurysms in the literature, likely resulting from increased tissue fragility in the suture line,[2] [23] no pseudoaneurysm formation was observed in our cohort.[17] [20] [22] A higher number of detached commissures, a larger preoperative SoV diameter, dissection of all three sinuses, the use of GRF glue, and an aortic annulus >27 mm are associated with a higher risk for root reoperation.[2] [8] [24]

 

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Limitations of the Study

This study presents the results of an observational retrospective analysis of one single center, introducing the possibility of medical and surgical management bias. Given the limited number of patients undergoing valve-sparing root replacement, it was not feasible to conduct a reliable comparison between the root-sparing and root replacement groups. Our study recruited patients over a 21-year period, wherein substantial changes in perioperative management were implemented. Follow-up was often conducted at affiliated institutions, introducing a higher degree of variation in echocardiographic reporting compared with the condition wherein assessments were performed in the same institution or in a core laboratory. Concerning aortic root dimensions, a significant number of missing values was noted in patients operated on before 2005, as computed tomography follow-up was not systematically performed in our institution before that time.

 

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Conclusion

Preserving the aortic root in ATAAD is a viable long-term surgical option with a low incidence of proximal reoperations. Patients presenting with moderate-to-severe preoperative AI can be managed with aortic root and valve preservation, under the premise that a competent aortic valve is obtained at the end of the procedure. However, a significant AI at first presentation, particularly when associated with extensive aortic root destruction affecting at least two of the three sinuses underscore the benefit to perform a valve-sparing root replacement to anticipate on the development of late AI. Additionally, strict echocardiographic monitoring is justified in patients with known risk factors for developing progressive AI such as important residual AI at discharge and progressive aortic root dilation to a diameter exceeding 45 mm. Further large-scale research is warranted to compare long-term outcomes between root-sparing and root replacement approaches.

 

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Conflict of Interest

None declared.

• References

• 1 Kim DJ, Lee S, Lee SH. et al. The fate of residual aortic regurgitation after ascending aorta replacement in type A aortic dissection. J Thorac Cardiovasc Surg 2020; 160 (06) 1421-1430.e5
• 2 Rylski B, Beyersdorf F, Blanke P. et al. Supracoronary ascending aortic replacement in patients with acute aortic dissection type A: what happens to the aortic root in the long run?. J Thorac Cardiovasc Surg 2013; 146 (02) 285-290
• 3 Beckmann E, Martens A, Pertz J. et al. Valve-sparing David I procedure in acute aortic type A dissection: a 20-year experience with more than 100 patients. Eur J Cardiothorac Surg 2017; 52 (02) 319-324
• 4 Piccardo A, Regesta T, Pansini S. et al. Fate of the aortic valve after root reconstruction in type A aortic dissection: a 20-year follow up. J Heart Valve Dis 2009; 18 (05) 507-513
• 5 Dang Van S, Laribi J, Pinaud F. et al. Preservation of the aortic root during type A aortic dissection surgery: an effective strategy?. Aorta (Stamford) 2021; 9 (02) 67-75
• 6 Dell'Aquila AM, Concistrè G, Gallo A. et al. Fate of the preserved aortic root after treatment of acute type A aortic dissection: 23-year follow-up. J Thorac Cardiovasc Surg 2013; 146 (06) 1456-1460
• 7 Ellauzi H, Zafar MA, Wu J. et al. Fate of preserved aortic root following acute type A aortic dissection repair. Semin Thorac Cardiovasc Surg 2022; 34 (02) 419-427
• 8 Ikeno Y, Yokawa K, Yamanaka K. et al. The fate of aortic root and aortic regurgitation after supracoronary ascending aortic replacement for acute type A aortic dissection. J Thorac Cardiovasc Surg 2021; 161 (02) 483-493.e1
• 9 Ro SK, Kim JB, Hwang SK. et al. Aortic root conservative repair of acute type A aortic dissection involving the aortic root: fate of the aortic root and aortic valve function. J Thorac Cardiovasc Surg 2013; 146 (05) 1113-1118
• 10 Chen SK, Qiu ZH, Fang GH, Wu XJ, Chen LW. Reported outcomes after aortic valve resuspension for acute type A aortic dissection: a systematic review and meta-analysis. Interact Cardiovasc Thorac Surg 2019; 29 (03) 331-338
• 11 Rosenblum JM, Leshnower BG, Moon RC. et al. Durability and safety of David V valve-sparing root replacement in acute type A aortic dissection. J Thorac Cardiovasc Surg 2019; 157 (01) 14-23.e1
• 12 Molteni M, De Chiara B, Casadei F. et al. Late echocardiographic study of aortic valve and aortic root after surgery for type A acute aortic dissection. J Cardiovasc Echogr 2016; 26 (03) 78-82
• 13 Pessotto R, Santini F, Pugliese P. et al. Preservation of the aortic valve in acute type A dissection complicated by aortic regurgitation. Ann Thorac Surg 1999; 67 (06) 2010-2013 , discussion 2014–2019
• 14 Vendramin I, Lechiancole A, Piani D. et al. Type A acute aortic dissection with ≥40-mm aortic root: results of conservative and replacement strategies at long-term follow-up. Eur J Cardiothorac Surg 2021; 59 (05) 1115-1122
• 15 De Paulis R, Cetrano E, Moscarelli M. et al. Effects of ascending aorta replacement on aortic root dilatation. Eur J Cardiothorac Surg 2005; 27 (01) 86-89
• 16 Bojko MM, Habertheuer A, Bavaria JE. et al. Recurrent aortic insufficiency after emergency surgery for acute type A aortic dissection with aortic root preservation. J Thorac Cardiovasc Surg 2021; 161 (06) 1989-2000.e6
• 17 Kirsch M, Soustelle C, Houël R, Hillion ML, Loisance D. Risk factor analysis for proximal and distal reoperations after surgery for acute type A aortic dissection. J Thorac Cardiovasc Surg 2002; 123 (02) 318-325
• 18 Leshnower BG, Myung RJ, McPherson L, Chen EP. Midterm results of David V valve-sparing aortic root replacement in acute type A aortic dissection. Ann Thorac Surg 2015; 99 (03) 795-800 , discussion 800–801
• 19 Valdis M, Adams C, Chu MWA, Kiaii B, Guo L. Comparison of outcomes of root replacement procedures and supracoronary techniques for surgical repair of acute aortic dissection. Can J Surg 2017; 60 (03) 198-204
• 20 Bekkers JA, Raap GB, Takkenberg JJ, Bogers AJ. Acute type A aortic dissection: long-term results and reoperations. Eur J Cardiothorac Surg 2013; 43 (02) 389-396
• 21 Kamohara K, Koga S, Takaki J, Yoshida N, Furukawa K, Morita S. Long-term durability of preserved aortic root after repair of acute type A aortic dissection. Gen Thorac Cardiovasc Surg 2017; 65 (08) 441-448
• 22 Russo CF, Mariscalco G, Colli A. et al. Italian multicentre study on type A acute aortic dissection: a 33-year follow-up†. Eur J Cardiothorac Surg 2016; 49 (01) 125-131
• 23 Yamanaka K, Hori Y, Ikarashi J. et al. Durability of aortic valve preservation with root reconstruction for acute type A aortic dissection. Eur J Cardiothorac Surg 2012; 41 (04) e32-e36
• 24 Casselman FP, Tan ES, Vermeulen FE, Kelder JC, Morshuis WJ, Schepens MA. Durability of aortic valve preservation and root reconstruction in acute type A aortic dissection. Ann Thorac Surg 2000; 70 (04) 1227-1233

Publikationsverlauf

Eingereicht: 14. Juni 2024

Angenommen: 06. November 2024

Artikel online veröffentlicht:
17. Juni 2025