Aortic Root Dilatation in Patients with Single Ventricle after Total Cavopulmonary Connection
Poznyak Yu. V.1, Rudenko N. M.1,2, Lebid I. G.1, Bairamov E. M.1, Dzurman D. O.1
1Ukrainian Children’s Cardiac Center, Kyiv, Ukraine
2Shupyk National Medical Academy of Postgraduate Education, Kyiv, Ukraine
Abstract. Extracardiac total cavopulmonary connection (EC-TCPC) is the end stage of single ventricle (SV) repair. The dilatation of the aortic root and proximal portion of the ascending aorta (Ao) has a progressive nature in this cohort of patients.
The purpose of this article is to analyze the dynamics of aortic root and proximal Ao dilatation in patients after EC-TCPC in the long-term period.
Material and methods. Between 2005 to 2016 y., 137 patients with SV underwent EC-TCPC with hospital mortality being 2.3% (n = 3). Pre- and postoperative data of the aortic root and ascending Ao sizes have been studied in 116 (84.7%) patients.
Result and discussion. According to the statistical data, Ao dilatation has been observed mainly in older patients (older than 10 years) at the time of TCPC, in patients with longer exposure to chronic hypoxemia. Transposition of the great arteries or pulmonary artery atresia proved to be major risk factors.
Conclusions. Aortic root and ascending Ao dilatation has a progressive nature in patients with functional SV long-term after TCPC. The patient’s age, initial SV anatomy (SV morphological type) are predictors of Ao dilatation.
Keywords: аortic root dilatation, total cavopulmonary connection, single ventricle.
The extracardiac total cavopulmonary connection (TCPC) has become widespread in many cardiac surgery institutions all over the world. There are a number of complications of this procedure, which further lead to the progression of heart failure and decrease the patient’s quality of life .
Despite the fact that EC-TCPC is the final stage of SV pathway, some patients undergo repeated surgical interventions after TCPC: systemic atrioventricular valve repair or replacement, EC revision or replacement [2, 7].
The dilatation of the aortic root and proximal portion of the ascending aorta (Ao) is a progressive increase of the diameter of one or more Ao sizes disproportionally to the child’s somatic growth or an increase in size by 1 cm per year or more in an adult patient [2, 3].
Significant Ao root dilatation leads to aortic insufficiency (AI), which, in turn leads to SV volume overload, an increase of SV end-diastolic parameters and remodelling of the myocardium with its subsequent diastolic and systolic dysfunction [4, 5, 7].
The purpose of this article is to analyse the dynamics of Ao root and proximal Ao dilatation in patients after EC-TCPC in the long-term after surgery.
Materials and methods. For the period from January 2005 to December 2016, 137 patients with SV aged 3 to 28 year (9.97 ± 4.37 years) underwent TCPC procedure. 134 (97.7%) were discharged from hospital, hospital mortality was 2.3% (n = 3). Concomitantly with TCPC, 7 (5.6%) patients underwent Damus-Kaye-Stansel (DKS) procedure and 2 (2.6%) underwent Ao root cardiac surgical procedures, which were not included in this analysis.
125 patients (93.3%) underwent dynamic long-term follow-up from 6 months to 11 years, on an average 48.2 ± 18.4 months (4.0 ± 1.5 years). 116 (84.7%) of the observed patients were divided into two groups: Group I – with aortic root and ascending Ao dilatation, Group II – without dilation.
In group I (n = 67) patients mean age was 167 ± 29 (90 – 297) months, in group II (n = 49) – 77 ± 14 months (36 - 99) months.
The main method for evaluation was transthoracic echocardiography (ECHO). Dynamic examination was performed every 6-12 months after TCPC including ECHO, ECG, blood saturation measurement, 6-minute walking test, blood pressure measurement.
At latest examination, the functional status of 82 (70%) patients corresponded to NYHA class I, 31 (28%) – class II and of 3 (2%) – class III. The diastolic blood pressure on both hands was 55 ± 5 mm Hg.
According to complex transthoracic echocardiography aortic root diameter and proximal portion of the ascending Ao was determined in β-mode in a parasternal position along the long axis at the level of the fibrous ring, sinuses of Valsalva, sinotubular junction and proximal portion of the ascending Ao with a subsequent calculation of z-score for every size.
A five-chamber and suprasternal position with the mode of pulse-wave and continuous wave Doppler were used to measure maximum and mean Ao systolic gradient. AI degree was assessed as minimal, mild, moderate, and severe. In the long-term postoperative period 4.5% (n = 5) of patients had moderate AI. AI occurrence and progressive increase was associated with root dilatation.
Results. In group I, the diameter at the level of the fibrous ring averaged 25.4 ± 1.5 mm, compared to group II – 22.6 ± 1.3 mm, p <0.05; at the level of sinuses of Valsalva – 35.6 ± 1.9 mm in group I and 30.8 ± 1.4 mm in group II, p <0.05; at the level of the sinotubular junction – 30.3 ± 1.7 mm in group I in comparison with 27.7 ± 1.5 mm in group II, p <0.05; at the level of the proximal portion of the ascending Ao – 35.3 ± 1.7 mm in group I and 30.9 ± 1.6 mm in group II, p <0.05.
Accordingly, Ao root z-score averaged: at the level of the fibrous ring – 2.7 ± 0.3 in group I and 1.9 ± 0.2 in group II, p <0.05; at the level of sinuses of Valsalva – 3.9 ± 0.3 in group I, 2.9 ± 0.2 in group II, p <0.05; at the level of the sinotubular junction 3.0 ± 0.2 in group I compared with 2.9 ± 0.3 in group II, p <0.05; at the level of the proximal portion of the ascending Ao – 4.1 ± 0.3 in group I, 3.0 ± 0.1 in group II, p <0.05.
Discussion. The analysis of the data of the two groups clearly showed that the patient’s age at the time of surgical treatment was higher in group I compared to group II (167 ± 29 months vs 77 ± 14 months, p <0.05). A statistically significant increase of one of the three Ao root sizes long-term after surgery was observed in patients of group I, where the older children prevailed (p <0.05). This fact suggests that older age (more than 10 years) at TCPC is the risk factor of aortic root and ascending Ao dilatation in the long-term afteroperation. The interval between the bidirectional Glenn’s procedure and TCPC was also significantly longer in group I – 39.5 ± 9.3 months vs. 21.3 ± 7.1 months, (p <0.05). The patients in group I had lower levels of saturation and higher haemoglobin level at the time of TCPC by clinical and laboratory analyses. The impact of chronic hypoxemia and cyanosis on the morphofunctional changes at the tissue level of the Ao wall is not excluded [4, 5].
The study of baseline anatomy and anatomical features of the great arteries in 71% (n = 83) patients of group I showed a transpositional course (p <0.05) and/ or atresia of the pulmonary artery (p <0.05). The prevalence of the morphologically dominant left ventricle (tricuspid atresia, double inlet ventricle) in group I also demonstrated.
Conclusions. The dynamic observation of patients with SV showed the progression of the aortic root and proximal ascending Ao dilation long-term after TCPC, predominantly in elderly patients (over 10 years of age) at the time of surgery, consistent with longer existence of chronic hypoxemia and polycythaemia. The risk factors included functionally SV anatomy with transposition of the great arteries or pulmonary artery atresia.
1. Pundi KN, Johnson JN, Dearani JA, Pundi KN, Li Z, Hinck CA, et al. 40-Year Follow-Up After the Fontan Operation: Long-Term Outcomes of 1,052 Patients. J Am Coll Cardiol. 2015 Oct;66(15):1700–10. https://doi.org/10.1016/j.jacc.2015.07.065
2. Cozijnsen L, Braam RL, Waalewijn RA, Schepens MA, Loeys BL, van Oosterhout MF, et al. What Is New in Dilatation of the Ascending Aorta? Review of Current Literature and Practical Advice for the Cardiologist. Circulation. 2011 Mar;123(8):924–8. https://doi.org/10.1161/CIRCULATIONAHA.110.949131
3. Jain D, Dietz H, Oswald G, Maleszewski JJ, Halushkaa MK. Causes and histopathology of ascending aortic disease in children and young adults. Cardiovasc Pathol. 2011 Jan-Feb;20(1):15–25. https://doi.org/10.1016/j.carpath.2009.09.008
4. Kim YY, Rathod RH, Gauvreau K, Keenan EM, Del Nido P, Geva T. Factors associated with severe aortic dilation in patients with Fontan palliation. Heart. 2017 Feb;103(4):280–6. https://doi.org/10.1136/heartjnl-2016-309615
5. Kojima T, Kuwata S, Kurishima C, Iwamoto Y, Saiki H, Ishido H, et al. Aortic root dilatation and aortic stiffness in patients with single ventricular circulation. Circ J. 2014;78:2507–11.
6. Erez E, Tam VK, Galliani C, Lashus A, Doublin NA, Peretti J. Valve-sparing aortic root replacement for patients with a Fontan circulation. J Heart Valve Dis. 2012 Mar;21(2):175–80.
7. Francois K. Aortopathy associated with congenital heart disease: A current literature review. Ann Pediatr Cardiol. 2015 Jan-Apr;8(1):25–36. https://doi.org/10.4103/0974-2069.149515
8. Egan M, Phillips A, Cook S. Aortic Dissection in the Adult Fontan with Aortic Root Enlargement. Pediatr Cardiol. 2009 May;30(4):562–3. https://doi.org/10.1007/s00246-009-9435-0
Published: March 2019