Due to high mortality associated with aortic dissection, anesthetic management of patients with Marfan syndrome with severe aortic root dilation is a challenging situation.
A patient with Marfan syndrome who came for retinal surgery to our institute is described here. A 12 year old male with retinal detachment and no systemic complaints presented for retinal surgery. Based on the clinical findings, the other investigations like echo revealed an aortic root dilation, MVP, MR and AR.
Aortic dissection in patients with MFS and severely dilated aortic root can be precipitated by major haemodynamic changes under anaesthesia. Careful haemodynamic monitoring and avoidance of haemodynamic swings can prevent this life threatening event.
Marfan Syndrome (MFS) is a systemic disorder of connective tissue with autosomal dominant inheritance. The diagnosis of MFS is based on identification of a combination of clinical manifestations in the ocular-musculo- skeletal and cardio-vascular organ systems defined in Ghent Nosology (De paepe et al 1996). Confirmation of the diagnosis requires the presence of major clinical manifestations in at least two organ systems associated with the involvement of a third organ system. Major clinical criteria are very specific for MFS and include a combination of (4 out of 8) skeletal manifestations, ectopia lentis, dural ectasia and dilation and dissection of ascending aorta (8487722). The major cardio-vascular manifestation in MFS is a progressive dilatation of ascending aorta, leading to aortic aneurysm formation and eventually to fatal aortic rupture or dissection.
A 12 year old boy (weighing 19.8 kgs) having been scheduled for retinal surgery (Lensectomy + Vitrectomy + belt buckle + Endolaser + silicon oil injection) following retinal detachment. During preoperative anaesthetic evaluation, his height was 142.5 cm and arm span 150 cms.
Arachanodactyly was found in fingers and toes. Airway examination showed high arched palate with Mallampati grade II (3592174). On auscultation, an early diastolic murmur was detected in the second right intercostal space close to sternum. A case of Marfan syndrome was suspected and an echo cardiography was requested. The echocardiogram revealed severe aortic root dilatation. (root diameter 42 mm) with aortic and mild mitral regurgitation and grade II Mitral Valve Prolapse (17487218). Left ventricular EF was 50%. CXR showed mediastinal widening with cardiomegaly. The patient’s haemogram was unremarkable. High risk was explained to parents and written consent was obtained as per our hospital protocols. The patient was kept nil per mouth as per universal guidelines. A general anaesthesia with controlled mechanical ventilation was planned. The premedication with I.M. Glycopyrolate (0.004 mg/kg) was given 1 hour preoperatively and the patient was wheeled inside OR. The monitoring included ECG, NIBP, SaO2 and ETCO2 . He was slowly induced with thiopentone sodium (5 mg/kg), Fentanyl 1.5 mg/kg, Vecuronium (0.1 mg/kg). The vocal cords were sprayed with Lignocaine10 % to reduce intubation response. The patient was maintained on O2, N2O and Isoflurane for the duration of the surgery (3 hours). Intra-operatively vitals were well maintained. The general anaesthesia was also supplemented by peribulbar block with 0.5% bupivacaine.
At the end of the surgery, the residual paralysis was reversed by neostigmine and glycopyrolate. Patient was observed in PACU for 2 hours and then shifted to the ward.
“Elastic fibre degeneration” lacking of smooth muscle cells in aorta and muco poly saccharide deposition in between the cells of media are the main features of aorta in Marfan syndrome (16325700). This is known as “Cystic medical degeneration”. Reduced distensibility of aorta with haemodynamic changes occurs as a result.
The aortic root dilatation is commonly accompanied by MVP, aortic regurgitation and also mitral regurgitation (11159287). During childhood and adolescence in Marfan syndrome, mitral Valve dysfunction as well as aortic abnormalities develop and progress gradually, often without symptons but may cause considerable morbidity and mortality by the end of second decade (6869287).
Aneurysmal dilatation of aorta is a common compilation of Marfan’s syndrome and may become manifest at an early age. The aortic dilatation can progress rapidly, even in the absence of symptoms (24348301). Individuals with Marfan syndrome should have annual echocardiographic examination to monitor aortic root dimensions. Those exhibiting rapid progression of aortic dilatation or an aortic root diameter in excess of 50 mm should be considered for elective composite graft repair of the aorta (20232788).
Volatile anaesthetics have the potential to decrease the force of cardiac ejection , thus reducing the risk of aortic dissection. Avoidance of excessive endogenous catecholamine production through control of pain and anxiety is essential.
This happens to be a rare case of severe aortic root dilatation diagnosed on routine pre anaesthetic evaluation that came up for retinal surgery.
A well planned anaesthetic management with close haemodynamic monitoring and good intra and post operative pain relief is a key to success in ophthalmic surgeries undertaken in patients afflicted by MFS.
Conflict of Interest – None declared.