Case ReportDouble Valve Replacement in a Patient with Maroteaux – Lamy syndrome. An Ultimate Team Challenge.


 BackgroundThe Maroteaux-Lamy syndrome (Mucopolysaccharidosis type VI) is a rare, inherited metabolic disease that results in progressive tissue accumulation of dermatan-sulfated glycosaminoglycans and inflammatory consequences that almost always affects the heart valves. From the anesthesia point of view, these rare cases are a serious challenge since the features of the syndrome entail difficulties in airway management and ventilation. It’s more than possible that the surgical team will perform a non-straightforward procedure.Case presentationA 42 year old male with Maroteaux-Lamy syndrome was referred to our department with shortness of breath, due to severe aortic stenosis, and at least moderate mitral valve regurgitation.The patient was initially scheduled for aortic valve replacement. After multiple attempts with video assisted laryngoscopy, the endotracheal intubation was achieved with the aid of fiberoptic bronchoscopy, while the ventilation succeeded only with laryngeal mask. The somatic features of the syndrome that made the anesthesia induction extremely difficult, also affected the surgical procedure. Suboptimal exposure of the mitral valve, patch enlargement of the aortic root to host the bigger possible prosthesis, and the hard decision to replace the mitral valve even with a marginal indication were the intraoperative difficulties for the surgical team.Finally, the patient underwent a successful double valve replacement with aortic root enlargement and after 18 months remains improved.ConclusionPatients with Maroteaux-Lamy syndrome represent a challenge for both anesthesiologists and cardiac surgeons. The whole team should be well prepared to deal with difficulties in airway management, ventilation and surgical valve exposure. The cardiac surgeon should be ready to offer additional procedures and even replace “prematurely” a moderately diseased valve in order to avoid a dangerous reoperation. The limited knowledges on the natural history and progression of the Maroteaux-Lamy syndrome valvulopathy and the difficulties in anesthesia induction support this approach.


Abstract Background
The Maroteaux-Lamy syndrome (Mucopolysaccharidosis type VI) is a rare, inherited metabolic disease that results in progressive tissue accumulation of dermatan-sulfated glycosaminoglycans and in ammatory consequences that almost always affects the heart valves. From the anesthesia point of view, these rare cases are a serious challenge since the features of the syndrome entail di culties in airway management and ventilation. It's more than possible that the surgical team will perform a nonstraightforward procedure.

Case presentation
A 42 year old male with Maroteaux-Lamy syndrome was referred to our department with shortness of breath, due to severe aortic stenosis, and at least moderate mitral valve regurgitation.
The patient was initially scheduled for aortic valve replacement. After multiple attempts with video assisted laryngoscopy, the endotracheal intubation was achieved with the aid of beroptic bronchoscopy, while the ventilation succeeded only with laryngeal mask. The somatic features of the syndrome that made the anesthesia induction extremely di cult, also affected the surgical procedure. Suboptimal exposure of the mitral valve, patch enlargement of the aortic root to host the bigger possible prosthesis, and the hard decision to replace the mitral valve even with a marginal indication were the intraoperative di culties for the surgical team.
Finally, the patient underwent a successful double valve replacement with aortic root enlargement and after 18 months remains improved.

Conclusion
Patients with Maroteaux-Lamy syndrome represent a challenge for both anesthesiologists and cardiac surgeons. The whole team should be well prepared to deal with di culties in airway management, ventilation and surgical valve exposure. The cardiac surgeon should be ready to offer additional procedures and even replace "prematurely" a moderately diseased valve in order to avoid a dangerous reoperation. The limited knowledges on the natural history and progression of the Maroteaux-Lamy syndrome valvulopathy and the di culties in anesthesia induction support this approach.

Background
Maroteaux-Lamy syndrome, rst described by Maroteaux in 1963, is a rare, inherited metabolic disease, caused by mutations in the gene coding for N-acetylgalactosamin-4-sulfatase, a lysosomal enzyme involved in the degradation of dermatan sulfate [1]. Dermatan-sulfated glycosaminoglycans are a prominent component of normal cardiac valve tissue, so their progressive accumulation and in ammatory consequences result in left heart valve degeneration. Nearly all patients with Maroteaux-Lamy syndrome will develop cardiac valve thickening, and dysfunction requiring valve replacement during their life course [2]. It is more than probable, that the procedure will not be straightforward due to the physical characteristics of these patients. In the literature, there are only few reports of double valve replacement in patients with this syndrome. We present our experience highlighting the intraoperative management, and decision making.

Case Presentation
A 42 year old male with diagnosed MLS since childhood was referred to us due to symptomatic severe aortic stenosis, along with at least moderate mitral valve regurgitation. The patient was presented in sinus rhythm, with short trunk (H 135cm, W 40kg), stiff neck, limited joints mobility, large tongue, limited leak. The aortic prosthesis mean and peak gradients were 11, 8 and 22, 8 mmHg respectively, and the aortic peak velocity 2, 39 m/sec. The mitral prosthesis peak gradient was 6, 63 m/sec.

Discussion And Conclusions
The Maroteaux-Lamy syndrome prevalence varies among populations from 0.0132 to 20.0/100000 newborns [1]. Despite the heterogeneity of the syndrome phenotype, mental development is usually normal, and cardiac valve pathology is present in almost all individuals. Somatic features of the syndrome are growth retardation, dwar sm, coarse facial features, joint stiffness, dysostosis multiplex, hepatosplenomegaly, corneal clouding, macrocephaly, hearing loss, and umbilical, or inguinal hernias [2].
Speci c features of the syndrome constitute a great challenge for both anesthesiologists and cardiac surgeons. Neck stiffness, large tongue, small mouth opening, tracheobronchial narrowing, chest deformities and poor ribs mobility, all represent challenges for airway management and ventilation. Fatal events during anesthesia induction have been described in the literature [3].
Di cult sternal retraction due to skeletal abnormalities and consequently problematic mitral valve exposure, along with the inconveniently small aortic and mitral annulus with increased patient-prosthesis mismatch possibility, constitute the intraoperative challenges for the cardiac surgeon.
In the literature, bail out maneuvers like implanting a reversed aortic prosthesis in the mitral position or aortic root enlargement, such as the modi ed Nick's we offered to our patient are extremely rare [4].
In addition to the technical di culties, hard intraoperative decisions will be taken, especially in cases of a second moderately diseased valve, sach as the mitral valve of our patient. Performing a double valve replacement de nitely increases the operative risk. Leaving unaddressed the second diseased valve exposes the patient to an increased risk of a di cult reoperation. Previous papers proposed a nonaggressive approach with the second diseased valve, expecting stabilization with the enzyme replacement therapy [5]. Unfortunately, recent scienti c data suggest that enzyme replacement therapy has no effect on the diseased valve [6].
The need to avoid a dangerous reoperation should in uence the decision regarding the second diseased valve.
In conclusion, patients with Maroteaux-Lamy syndrome represent a heart team challenge. Proper cardiac anesthesia and cardiac surgery preparation are mandatory for the management of such a rare and vulnerable patients. An additional "premature" replacement of a second moderately diseased valve might be a useful option.

Abbreviations
No abbreviations used.