Congenital heart disease COARCTATION OF THE AORTA FROM FETUS TO ADULT: CURABLE CONDITION OR LIFE LONG DISEASE PROCESS?

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1 Congenital heart disease COARCTATION OF THE AORTA FROM FETUS TO ADULT: CURABLE CONDITION OR LIFE LONG DISEASE PROCESS? Take the online multiple hoie questions assoiated with this artile (see page 1488) FETAL Correspondene to: Dr Eri Rosenthal, Guy s Hospital, Department of Paediatri Cardiology, St Thomas Street, London, UK; Eri.Rosenthal@gstt.nhs.uk C Eri Rosenthal Heart 2005; 91: doi: /hrt oartation of the aorta was desribed pathologially in the 1700s and linial reognition ourred from the early 1900s. w1 w2 Postmortem data suggested a median age of death of 31 years mainly from ompliations of the oartation (ardia failure in 26%, aorti rupture in 21%, baterial endarteritis in 18%, and intraranial haemorrhage in 12%. w3 w4 The presurgial natural history data were similar aepting the ase seletion bias prevalent in that era. w5 Surgial repair was first desribed in 1945, balloon dilation in 1982, and stent implantation in w6 8 Currently, the linial diagnosis (murmur, upper limb hypertension, and absent or diminished femoral pulses) an rapidly be onfirmed non-invasively by ehoardiography and magneti resonane imaging (MRI), and monitored by these tehniques following treatment (fig 1). Radiofemoral delay is a poor marker for follow up. 1 w9 The vast majority of oartations are identified and treated in the first year of life and adult presentation is beoming less frequent. Coartation of the aorta aounts for approximately 7% of all live births with ongenital heart disease and is 1.7 times more ommon in males. w10 w11 Hypoplasia of the aorti arh to various degrees is a ommon aompanying feature. w12 There is a signifiant assoiation with other ardia lesions (ventriular septal defet, patent arterial dut, and biuspid aorti valve (in up to 50%) ommonly but also with omplex defets); in some the prognosis depends more on the outome of the assoiated lesions whih requires simultaneous management with the oartation while in others the assoiated lesion is mild and an be treated on its own merits. In Turner s syndrome (46 XO) oartation is present in 10% of patients. w13 While oartation is readily diagnosed and treated in general, there are a few areas of ontention and unertainty. A serious onern is the failure to diagnose reliably the ondition antenatally or at birth, so that even in the urrent era neonates who are linially normal remain undiagnosed until they present with a sudden ollapse and are at risk of onsiderable morbidity and mortality. While hoie of the primary therapeuti intervention may generate some ontroversy, perhaps the most unertain area is the definition of satisfatory orretion and whether this an be onsidered a ure. It is unlear how important it is to obtain a perfet result with treatment and whether a mild degree of reoartation an be aepted. 2 w14 There is doubt as to whether all mild native oartations should be treated. DIAGNOSIS Before birth the fetal irulation is able to ope with oartation (indeed it also opes with omplete interruption at the oartation site). Venous return to the left ventrile is via the foramen ovale and its output is via the asending aorta to the head and arms. Pressure in the right ventrile is the same as in the left ventrile and the majority of its output is direted via the arterial dut to the desending aorta to supply the abdomen and legs. Thus blood pressure above and below the potential oartation site is idential with little flow aross the isthmus between the left sublavian artery and the arterial dut (fig 2). It is therefore surprising that the ardiovasular system responds to the oartation in utero, with right ventriular dilation that an be deteted by fetal ehoardiography (fig 3A). w15 Right ventriular dilation is, however, not a speifi sign of postnatal oartation with a signifiant number of false positives espeially when based on right ventriular dilation only in late gestation. 3 In those with more severe oartation or with additional transverse arh hypoplasia, there is a signifiant disproportion in the size of the aorti arh (smaller than normal) and main pulmonary artery (larger than normal) (fig 3B). Thus the antenatal findings are of ventriular disproportion (earlier in gestation being more important) and great vessel disproportion (more sensitive than ventriular disproportion alone). The oartation site itself is not easily identifiable beause of the lak of flow and the presene of the arterial dut that overlies it (figs 2B and 3B). The ability to detet these hanges is variable, with a high suess rate in fetal ardiology units but only a low rate in general obstetri units where great vessel assessment is not routine and mild ventriular disproportion alone is 1495 Heart: first published as /hrt on 17 Otober Downloaded from on 21 July 2018 by guest. Proteted by opyright.

2 reverse shunting aross the foramen ovale and ontinued evaluation is required until term Figure 1 Magneti resonane imaging sans of native oartation in a 32 year old man (A) and aneurysm at balloon dilation site in a 14 year old boy (B). ignored. w16 w17 The presene of signifiant extraardia fetal abnormalities or markers of hromosomal anomalies improves the detetion rate as detailed fetal ehoardiography is then undertaken. w18 In a large fetal ehoardiography series of 144 fetuses with suspeted oartation, two out of three were normal at birth. Of those suspeted to have a oartation and a ventriular septal defet, two thirds had a ventriular septal defet only postnatally. 3 In some fetuses, the ventriular disproportion is so pronouned that it is diffiult to be ertain that the fetus is not progressing to a hypoplasti left heart syndrome. In these there may be NEONATAL AND INFANTILE PRESENTATION Antenatally diagnosed Where there is strong suspiion antenatally that a severe oartation with aorti arh hypoplasia is likely (and the neonate is at risk from dut losure), the fetus should be delivered in a paediatri ardiology entre and a prostaglandin infusion ommened immediately to maintain dutal pateny. The early ehoardiogram is revealing and when it onfirms arh hypoplasia and a posterior shelf at the oartation site, prostaglandins are maintained until surgial repair a few days later. Where the suspiion is less strong, the fetus is delivered and observed losely without prostaglandins. As long as there are no features on ehoardiography as above, the dut is allowed to lose spontaneously with daily or alternate daily ehoardiograms and regular monitoring of the four limb blood pressure and femoral pulses until it is lear whether a oartation is present or not. Those without a oartation are allowed home after dut losure but should be reviewed again in 4 6 weeks and finally at six months as there is oasional late detetion of oartation in this ohort. 3 Postnatally diagnosed Neonates who ollapse are fully resusitated before transfer and surgery. Intubation, mehanial ventilation, inotropes, and orretion of the severe metaboli aidosis are needed. Prostaglandins are given in an attempt to reopen the arterial dut whose losure usually preedes the ollapse. Dut losure auses ollapse by a number of mehanisms. In some, where the oartation is very severe, all lower body Figure 2 Diagram of normal fetal irulation. (A) Superior vena ava (SVC) blood flow (blue arrow) is direted through the triuspid valve to the pulmonary artery and via the arterial dut to the lower body segment. Inferior vena ava (IVC) blood flow (red arrow) ontaining oxygenated blood from the plaenta is direted aross the foramen ovale to the left ventrile, asending aorta and upper body segment with little flow aross the isthmus between the left sublavian artery and the arterial dut. (B) Coartation of the aorta in utero does not affet the fetal blood flow pattern. (C) After birth there is a fall in pulmonary resistane with inreased pulmonary blood flow (blue arrows) and forward flow from the aorti arh to the desending aorta (red arrow). (D) As the dut onstrits, the narrowing of the oartation is aentuated and the inreasing obstrution leads to a gradient (red dotted line). Heart: first published as /hrt on 17 Otober Downloaded from on 21 July 2018 by guest. Proteted by opyright.

3 blood flow has been via the dut; one it loses, lower body hypoperfusion leads to profound aidosis and ventriular dysfuntion. In others the ampulla of the dut serves as a bypass hannel past the oartation shelf obstrution inreases as the dut loses. There is also dutal tissue in the oartation segment of the aorta, whih onstrits the aorta further as the dut loses. Closure of the dut does not always lead to instantaneous ollapse, but with severe oartation the raised left ventriular afterload is eventually not tolerated any longer. Neonates and infants in whom the diagnosis is established beause of absent femoral pulses, a murmur, or development of mild ardia failure are admitted at the time of diagnosis for surgery. Rarely the infant presents with the appearane of a dilated ardiomyopathy and a low gradient aross the oartation (aused by poor ardia output), whih an ause diagnosti diffiulty. CHILDHOOD, ADOLESCENT, AND ADULT PRESENTATION In later life the finding of a oartation is usually an inidental disovery, although in some symptoms do our whih may even be life threatening (table 1). w19 Diagnosti findings Findings on hest x ray and ECG range from none to signs of ventriular hypertrophy and dilation. Rib nothing from ollateral vessels and the 3 sign of indentation in the aorti shadow are seen on the hest x ray in older hildren and adults. TREATMENT Surgial repair Surgial repair is usually performed via a left lateral thoraotomy and involves lamping the aorta above and below the oartation segment so that lower body blood flow is only via ollaterals (if they have developed). The three standard approahes were resetion and end-to-end anastomosis, sublavian flap repair (ligation of distal sublavian artery to use the proximal portion to overlay path the oartation segment), and pathing with foreign material (usually a Daron path), while interposition grafting or arotid to desending aorta shunting were used muh less frequently. w20 24 All three tehniques were aompanied by a low rate of morbidity and mortality but a definite rate of Table 1 Presentation of oartation Figure 3 (A) Disproportion between the right and left ventriles is striking. (B) Great vessel disproportion between the aorta (Ao) and pulmonary artery (PA) is more speifi for oartation than ventriular disproportion. LV, left ventrile, RV, right ventrile; SVC, superior vena ava. Fetus ventriular disproportion great vessel disproportion assoiated with other ongenital heart disease nuhal thikening/hromosomal abnormality (Turner s syndrome) Neonate ollapse, aidosis heart failure systoli/ontinuous murmur onduted to bak weak or absent femoral pulses upper limb hypertension Infant heart failure systoli/ontinuous murmur onduted to bak weak or absent femoral pulses upper limb hypertension ardiomyopathy rarely Child, adolesent, and adult systoli/ontinuous murmur onduted to bak (ollateral murmurs over sapula rarely) weak or absent femoral pulses (radio-femoral delay in older patients) upper limb hypertension exerise intolerane leg fatigue and laudiation old feet ardia arrest (left ventriular hypertrophy and arrhythmia) hypertensive retinopathy intraranial bleed aorti dissetion/rupture infetive endoarditis reoartation that was highest when performed in neonates (up to 19%) and infants. 4 The Daron path tehnique was also aompanied by a high inidene of aneurysms at the repair site and is no longer used. w25 w26 The sublavian flap tehnique resulted in loss of the pulses in the left arm, whih were eventually reonstituted via ollaterals. Blood pressure remained lower in this limb and oasionally there was a redution in arm length. w27 It was not used in adults for fear of limb ishaemia. Very rarely laudiation or a sublavian steal syndrome ould our in later life. w Heart: first published as /hrt on 17 Otober Downloaded from on 21 July 2018 by guest. Proteted by opyright.

4 1498 While resetion and end-to-end anastomosis remains the mainstay of surgery, modifiations to treat simultaneously the hypoplasti transverse arh have developed. These inlude the end-to-side anastomosis and extended aorti arh repairs. 5 w29 w30 In addition to reseting the oartation segment, the desending aorta is anastomosed onto the underside of the aorti arh thereby shortening the arh and simultaneously orreting the oexistent arh hypoplasia during surgery the upper lamp needs to inlude the left arotid artery. Currently this an be performed with a low morbidity and mortality and a reoartation rate as low as 3%. 6 Where the arh is partiularly hypoplasti, homograft tissue an be used to augment the repair, whih in that situation may need to be performed via a midline sternotomy on ardiopulmonary bypass (whih is also used when additional ardia lesions are repaired at the same time). Whether this approah is neessary for loalised oartation with mild transverse arh hypoplasia or even at all is subjet to ontroversy. Many believe that adequate treatment of the oartation site alone results in rapid remodelling of the hypoplasti arh though others have found a signifiant inidene of arh obstrution after suessful oartation repair. 7 w31 33 Paraplegia as a ompliation of surgery ours in 0.3% and is related to dissetion and interruption of ollateral and interostal vessels or when ollateral vessels around the oartation are absent with low distal pressure during aorti ross lamping (table 2). It seems to be more of a problem for repeat surgery involving extensive dissetion when the ollaterals have diminished and may be as high as 2.6%. w34 36 Paraplegia an our weeks after surgery. 8 There has been a move to perform late ompliated repeat surgery with ardiopulmonary bypass and deep irulatory arrest or with left heart bypass through a lateral thoraotomy, reduing the earlier morbidity and mortality and allowing full rather than palliative treatment. w36 39 Table 2 Compliations of treatment Left thoraotomy approah bleeding, haemothorax hylothorax reurrent laryngeal nerve palsy phreni nerve palsy Horner s syndrome paradoxial hypertension (risk of suture leak) paraplegia left arm impaired growth/ishaemia (sublavian flap repair) vertebro-basilar ishaemia (sublavian flap repair) erebral ishaemia (extended arh repair) Cardiopulmonary bypass bleeding erebral ishaemia myoardial dysfuntion reurrent laryngeal nerve palsy Horner s syndrome paradoxial hypertension (risk of suture leak) Catheter intervention femoral artery olusion/pseudoaneurysm aorti dissetion/aneurysm/rupture paraplegia (? with overed stent) stent migration/malposition Catheter intervention Balloon dilation was introdued for the treatment of reoartation to avoid the risks of repeat surgery and subsequently used to treat native oartation. w40 Its mehanism of ation is by strething and tearing of the thikened intimal shelf and adjaent media layers. Tears of the adjaent normal aorti wall also our, perhaps refleting an inherent weakness in the aorta in patients with oartation. w41 Limiting the damage to the oartation shelf ould not be guaranteed and it gained only modest aeptane in native oartation where there was less surgial sarring to support the aorti wall and where the results of surgery were felt to be superior. Aute rupture and dissetion is rare but aneurysms an develop later. w42 It is generally avoided in the first 6 12 months of life beause of a high inidene of reoartation and femoral artery damage. w43 A single randomised trial omparing balloon dilation with surgery revealed aneurysms in 0% of the surgial patients and 20% in the patients undergoing balloon dilation, although none were signifiant enough to need an intervention. w44 There are numerous reports, however, of balloon dilation series without any aneurysm formation and equally of surgial series with aneurysms, so the influene of this one small study has been small. 9 w45 47 Overall the long term results are favourable and 10 w48 balloon dilation remains a first line option in many entres. The safety and effiay of atheter intervention were onsiderably inreased with the advent of perutaneous stent implantation. w8 The rationale for stent implantation is that over dilation of the oartation segment is unneessary, thus avoiding major transmural tears, while at the same time the stent struts will splint any smaller tears against the aorti wall preventing progressive dissetion and aneurysm formation. The aute elasti reoil of the oartation segment that ontributes to a suboptimal initial result and later reoartation is prevented by stent implantation, leading to a greater relief of obstrution than with balloon dilation alone. The size Figure 4 (A) Severe native oartation in adult with large gradient and ollateral vessels. (B) Stent implantation to 80% of the final aorti diameter abolishes the gradient. Heart: first published as /hrt on 17 Otober Downloaded from on 21 July 2018 by guest. Proteted by opyright.

5 of the delivery sheath that is required, however, preludes use in most hildren under 25 kg. While mild reoartations were not amenable to balloon dilation beause of the need for large balloons to overome the natural reoil and arrying greater risks of tearing, stent implantation allowed this type of lesion to be easily treated albeit with a small risk of stent migration. w49 w50 Exessive strething of a tight oartation, however, ould still lead to aneurysm formation and rupture so graded dilation, allowing for healing before further dilation, and overed stents are now employed to prevent this (fig 4). 11 w51 A partiular role for stent implantation is in the situation where aorti valve or root replaement or oronary bypass grafting is needed. Presurgial stenting of the oartation segment removes the need to disset the oartation area or try to reover from bypass in the fae of an aorti obstrution (fig 5). w52 w53 Covered stents now allow endovasular repair of assoiated aneurysms whether native, after surgery or atheter intervention. For loalised aneurysms and those in assoiation with residual oartation, stent delivery is via a perutaneous approah (fig 6). For extensive aneurysm formation, large ustom made self expanding stents are used whih are mounted on Frenh delivery systems and require femoral or ilia exposure. w54 Surgeryoratheterintervention? While many hold strong views addressed by Hanley in 1996 in most entres repair is by open surgery in the first year of life. 11 w55 61 In hildhood, surgery or balloon dilation are ommon approahes depending on the views of individual entres, while in adolesents and adults balloon dilation and stent implantation are more likely to be used than surgery. Reurrenes after surgery are invariably treated by atheter intervention in the first instane. FOLLOW UP While originally viewed as a simple disease proess that ould be ured by effetive surgery, it beame lear that this was not so. The first large long term series in 1987 of 226 survivors of oartation surgery with year follow up showed a 12% mortality and a freedom from hypertension of only 32% (despite normal blood pressure after surgery). w62 The Mayo lini series of patients operated on from 1946 to 1981 revealed a disturbing inidene of morbidity and mortality in the 571 survivors with a median follow up of 20 years. Further surgery was required in 11%, hypertension required treatment in 25%, and death ourred in 15% at a mean age of 38 years. Deaths were aused by oronary artery disease, sudden death, heart failure, erebrovasular aidents, and ruptured aorti aneurysm. The best long term survival ourred in those operated on before the age of 9 years. Systoli hypertension was preditive of late death. w63 A further long term study with year follow up of 254 survivors revealed a late ardiovasular mortality of 18% (oronary artery disease and reoperation being the most ommon auses of death) at a mean age of 34 years after surgery, and 35% were hypertensive. 12 All these studies suffer from the limitations of retrospetive analysis with inomplete follow up, learning urve, hanges in the surgial approah, and a non-uniform ohort with a wide age range at first operation and a differing duration and intensity of follow up. A fundamental problem in this field is the impreise definition of terms suh as reoartation and aneurysm. Signifiant oartation or reoartation has traditionally been defined as a gradient (stritly a atheter withdrawal gradient but also interhanged with arm/leg uff blood pressure and Doppler) of. 20 mm Hg together with hypertension. w64 Reently a more onservative definition has been proposed of hypertension (rest or exerise indued) and a non-invasive gradient. 30 mm Hg. w65 Some have ignored 1499 Figure 5 Gross dilation of the asending aorta (. 7 m) in an adult patient with mild oartation and a biuspid aorti valve, followed for 20 years without treatment. Stent implantation has been performed before aorti root replaement. Figure 6 (A) Small aneurysm (blak dots) at the top end of an unovered stent (white dots) plaed in a severe native oartation presenting with an out of hospital ardia arrest. (B) A overed stent (white lines) has been expanded inside the previous stent with exlusion of the aneurysm. Heart: first published as /hrt on 17 Otober Downloaded from on 21 July 2018 by guest. Proteted by opyright.

6 1500 mild hypertension, whih would impose long term treatment on young asymptomati patients. Some authors inlude gradients at the level of the hypoplasti arh as reoartation even when the atual oartation site is devoid of any narrowing. Aneurysm may be defined as a diameter. 1.5 times the adjaent normal diameter, but some mean dilation that mandates intervention. Long term outome of a single surgial strategy in a uniform age group (for example, extended arh repair in neonates) is still awaited. Hypertension The upper limb hypertension assoiated with untreated oartation usually responds dramatially to treatment. Paradoxial rebound hypertension may be present for hours to days in a small proportion with more severe oartation, but this usually subsides over a few weeks. Although a majority of patients will have a normal blood pressure after their initial intervention in the short term, some patients ontinue to manifest a mildly elevated blood pressure, and some with an initial good response go on to develop hypertension as many as one in three in long term studies. 12 w62 w63 In an adult ohort of 49 patients undergoing balloon dilation 63% were normotensive at a median of 10 years. 10 The ause for ongoing hypertension is likely to be multifatorial. In some patients there is a mild degree of residual oartation (, 20 mm Hg), whih onventionally has been onsidered to be aeptable, and in others there is mild hypoplasia of the transverse arh, whih was not onsidered to be important or a surgial target initially. Careful MRI assessment of the aorti arh geometry onfirms a higher inidene of hypertension in those with tortuous aorti arhes (possibly due to lak of remodelling/growth of the originally hypoplasti arh segment) despite similar degrees of residual narrowing at the original repair site. This has also been assoiated with an inreased left ventriular mass. 213w66 Other postulates inlude early renal hypoperfusion has reset the renin angiotensin aldosterone system or upper limb w67 w68 hypertension has reset the aorti baroreeptors. Even in those with aeptable resting blood pressures, exerise appears to unmask an exaggerated response in some both with and without mild residual gradients. In a Pratial point Blood pressure should always be measured in the right arm unless it is known that the right sublavian artery has an anomalous origin or was ligated surgially. The left sublavian artery may be amputated during sublavian flap repair, with a ombined end-to-end resetion and flap proedure or even with an extended arh repair to allow mobilisation of the arh. In rare patients it may originate at the level or even below the oartation site but even when normally plaed, it is distal to the transverse arh, whih may be narrowed or tortuous, and the pressure seen by the left ventrile and erebral irulation will be underestimated. Many osillometri sphygmomanometers are designed for use on the left arm and ambulatory monitors are deliberately plaed on the non-dominant arm (usually left) to improve reordings leading to inaurate measurements of the true blood pressure. Table 3 Compliations in adults Loal site reoartation, aneurysm, dissetion, rupture, fistula, endarteritis, myoti aneurysms Asending aorta aneurysm, dissetion, rupture, sinus of Valsalva fistula Left ventrile hypertrophy, dilation Aorti valve (biuspid valve), stenosis and regurgitation Coronary arteries premature atheroslerosis Cerebral vessels berry aneurysms, intraranial bleeds Abdominal vessels renal artery stenosis Systemi hypertension series of 35 adult patients undergoing surgial repair, 66% were normotensive off treatment although of these one third had an exaggerated blood pressure response to exerise. 14 In these patients an apparently adequate size repair site is postulated to be non-ompliant following surgery and fails to dilate during exerise. w69 Exerise indued hypertension orrelates with resting blood pressure but is not an independent preditor of inreased left ventriular mass. w70 Many have blamed late or imperfet surgery as the ause of the persistent hypertension. w71 Disappointingly therefore, O Sullivan et al found a 28% inidene of hypertension 10 years after repair in hildren. 15 Although the onfounding effets of small Doppler gradients were present (1 of 3, 3.5 m/s on Doppler, 2 of 3, 2.5 m/s) it does suggest that the pereived benefits of early surgery to prevent late hypertension may be to some extent due to the younger age of these patients and shorter duration of follow up. Left ventriular funtion Left ventriular hypertrophy after oartation repair is likely to be aused by a ombination of several fators: inreased afterload from small residual gradients, ongoing mild hypertension, exerise indued gradients or hypertension, biuspid aorti valve with progressive stenosis, and premature oronary disease. Left ventriular dilation is usually assoiated with biuspid aorti valve regurgitation possibly aentuated by arh or oartation obstrution and hypertension. w14 Coronary artery intimal thikening has been doumented in hildren with oartation w72 and this may be aentuated by persisting elevation in left ventriular afterload from mild hypertension or reoartation. Aneurysm formation Aneurysm formation after surgial repair has been observed most frequently in relation to repair with a Daron path, and this type of repair is no longer employed. The inidene after other forms of surgery is low when there is no assoiated infetion, whih in itself is rare. It has been noted after balloon dilation autely and even after stent implantation. 910w44 48 A biuspid aorti valve is present in 50% of patients with a oartation and reently has been found to have an independent assoiation with asending aorta dilation. w73 Heart: first published as /hrt on 17 Otober Downloaded from on 21 July 2018 by guest. Proteted by opyright.

7 Minor inreases in systemi blood pressure and/or a mild oartation site gradient may aentuate the asending aorta dilation proess in repaired oartation patients with a biuspid aorti valve (fig 5). A reent report of 235 adults (182 surgial repair, 28 atheter intervention, and 26 untreated) revealed a 16% inidene of asending or desending aorti wall ompliations ausing death or requiring a surgial or atheter intervention. 16 Asending aorta ompliations were three times as ommon as desending aorta (oartation site) ompliations. The age at repair and the type of surgial repair were surprisingly not preditive of aorti wall ompliations, but age at the time of the study and a biuspid aorti valve were preditive. Interestingly, those with mild oartation who had not been treated also had a 15% inidene of aorti wall ompliations. In a smaller study of 124 adults after oartation repair, a biuspid aorti valve was found in 62% and 28% required an aorti valve intervention. Asending aorta dilation was present in 28% defined as an asending aorta greater than 4.0 m. w74 Generalised vasulopathy Evidene for a more generalised vasulopathy is onfounded by definitions of a satisfatory repair and oexistent hypertension. There is evidene that the peripheral vasular beds proximal and distal to the oartation site behave differently. Typially there is an elevated forearm resistane and redued hyperaemi response, whih is absent in the lower limb, and the magnitude of impairment seemed to orrelate with the age at surgial repair. w75 w76 The differential vasular response is also postulated as a ause of exerise indued gradients and hypertension after satisfatory oartation repair indeed arm leg gradients of mm Hg an develop on exerise in those with normal resting blood pressure and normal Doppler flow over the oartation repair site. 17 w77 The pulsatility of the poststenoti aorta, whih is severely impaired before repair, does not return to normal when ompared to ontrols and the degree w78 w79 of impairment may orrelate with the age at surgery. In adults, intima media thikness in the preoartation segment (arotid artery) is greater than in the postoartation segment (femoral artery) after repair. Carotid intima media thikness is similar to normal ontrols in those with a good repair but thiker in those with residual hypertension, while the femoral intima media thikness is thinner in both ompared to normals. w80 There are no studies following these hanges serially in well stratified ohorts of patients after oartation repair. Pregnany Detetion for the first time during a pregnany often a murmur but oasionally severe hypertension or even aorti dissetion still ours. w81 w82 In general, pregnany is tolerated well by the mother and fetus as long as the hypertension is ontrolled and management of the pregnany is altered little. 18 Despite a higher inidene of pre-existing hypertension, there does not seem to be an inreased risk for pre-elampsia. Unontrolled hypertension together with the oestrogen indued weakening of the arterial walls and the inherent abnormality thought to be present in the aorta may lead to rupture, partiularly during straining in the seond stage but also up to six weeks postpartum. If the pregnant patient is found to have an aneurysm then onsideration should be given to a termination or early indution of labour Coartation of the aorta from fetus to adult: key points Antenatal diagnosis relies on detetion of ardiovasular hanges, but the oartation itself is rarely identified Despite a normal postnatal examination, neonatal oartation may remain undeteted until presentation with profound ollapse after dut losure There is evidene for a generalised vasulopathy but it is not known whether it develops in response to the haemodynami hanges in utero, is a ompliation of late or imperfet treatment, or whether it is an inherent part of the disease proess Hypertension and aorti dilatation, dissetion, and rupture remain a risk throughout life so that life long surveillane is required. and management of labour with an epidural to avoid straining during the seond stage. w83 Antibioti prophylaxis against infetive endoarditis is required for ompliated deliveries. There is also a risk of intraranial bleeding from berry aneurysms in this setting (table 3). w84 Ideally the woman with oartation, whether previously treated or not, should be fully evaluated before pregnany for the severity of the oartation/reoartation, aneurysm formation, asending aorta dilation, aorti valve disease, and ventriular dysfuntion so that any interventions an be performed eletively. Where there is evidene of an aneurysm (native or after previous treatment) pregnany is best avoided until it has been treated. Patients with Turner s syndrome are at inreased risk from aorti dissetion and those who have assisted oneption with egg donation and exogenous oestrogen may be at even greater risk. w85 CONCLUSIONS There are no large, long term studies of outome for surgial repair in infany. That the reoartation rate appears to be lower and aute morbidity and mortality are less for patients treated over the past 20 years is enouraging. Until further evidene arues, it would be prudent to onsider the patient with oartation to have an ameliorated but not ured ondition even after a perfet repair in infany. w86 Ongoing surveillane of the oartation site, asending aorta, aorti valve, blood pressure, and left ventriular funtion will be required for the foreseeable future. Blood pressure should be heked on a 6 12 month basis with impeable ontrol, left ventriular and aorti valve funtion every 1 3 years by ehoardiography, and oartation site and asending aorta every 2 5 years by ehoardiography and oasionally by MRI. At the very least, a baseline MRI should be performed in all adolesents and young adults who have undergone hildhood intervention and before a pregnany. We still do not know whether the ongoing degree of morbidity and mortality reflet inadequaies in the initial treatment either as a result of late diagnosis, aeptane of imperfet outomes of treatment beause they are pratial, or whether there is an independent underlying loal or generalised vasulopathy that is possibly the ause of oartation in the first plae and leads to a ontinuous effet on the ardiovasular system. Life long surveillane of both treated and untreated oartation patients is required to monitor and intervene for hypertension, aorti wall, and other ardiovasular ompliations Heart: first published as /hrt on 17 Otober Downloaded from on 21 July 2018 by guest. Proteted by opyright.

8 1502 Additional referenes appear on the Heart website ACKNOWLEDGEMENTS I am grateful to Dr JM Simpson for fig 2 and Dr SA Qureshi for fig 6. In ompliane with EBAC/EACCME guidelines, all authors partiipating in Eduation in Heart have dislosed potential onflits of interest that might ause a bias in the artile REFERENCES 1 Nielsen JC, Powell AJ, Gauvreau K, et al. Magneti resonane imaging preditors of oartation severity. Cirulation 2005;111: Combination of MRI derived flow veloity and aorti narrowing indexed to body surfae area predits atheter gradients in exess of 20 mm Hg. 2 Vriend J, Zwinderman A, de Groot E, et al. Preditive value of mild, residual desending aorti narrowing for blood pressure and vasular damage in patients after repair of aorti oartation. Eur Heart J 2005;26: Mild residual oartation is assoiated with inreased blood pressure and arotid intimal thikness. Should the threshold for intervention from urrent guidelines be lowered? 3 Head CEG, Jowett VC, Sharland GK, et al. Timing of presentation and postnatal outome of infants suspeted of having oartation of the aorta during fetal life. Heart 2005;91: Largest series of fetuses with suspeted oartation the diagnosis was onfirmed in one third postnatally. Coartation was only deteted late after dut losure in 7%. 4 Pfammatter JP, Ziemer G, Kaulitz R, et al. Isolated aorti oartation in neonates and infants: results of resetion and end-to-end anastomosis. Ann Thora Surg 1996;62: Signifiant re-oartation rate in neonates of 19%. 5 Younoszai AK, Reddy VM, Hanley FL, et al. Intermediate term follow-up of the end-to-side aorti anastomosis for oartation of the aorta. Ann Thora Surg 2002;74: Reoartation rate of only 5.5% by two years when performed in neonates with good response to balloon dilation. 6 Wood AE, Javadpour H, Duff D, et al. Is extended arh aortoplasty the operation of hoie for infant aorti oartation? Results of 15 years experiene in 181 patients. Ann Thora Surg 2004;77: Exellent results for repair of oartation and hypoplasti arh during a single operation in infany. 7 DiBardino DJ, Heinle JS, Kung GC, et al. Anatomi reonstrution for reurrent aorti obstrution in infants and hildren. Ann Thora Surg 2004;78: Sternotomy and ardiopulmonary bypass approah to repair arh hypoplasia not addressed during initial oartation surgery. Suggests that an initial omplete repair inluding the arh is preferable to a loal repair. 8 Peters P, Brennan JW, Hughes CF, et al. Late quadriplegia after adult oartation repair. Ann Thora Surg 2003;75: Management of late spinal ord ishaemia aused by thrombosis in spinal artery ollateral with spinal deompression. 9 von Kodolitsh Y, Aydin MA, Koshyk DH, et al. Preditors of aneurismal formation after surgial orretion of aorti oartation. J Am Coll Cardiol 2002;39: Aneurysms are more frequent with path repair and older age at repair. 10 Fawzy ME, Awad M, Hassan W, et al. Long-term outome (up to 15 years) of balloon angioplasty of disrete native oartation of the aorta in adolesents and adults. J Am Coll Cardiol 2004;43: Long term follow up in 49 patients. Repeat dilation was required and suessful in four patients. Small aneurysms not requiring treatment remained stable in four patients. Blood pressure was normal in 63% without mediation. 11 Hijazi ZM. Catheter intervention for adult aorti oartation: be very areful! Cathet Cardiovas Intervent 2003;59: Argument for overed stents as first line treatment of oartation/ reoartation. 12 Toro-Salazar OH, Steinberger J, Thomas W, et al. Long-term follow-up of patients after oartation of the aorta repair. Am J Cardiol 2002;89: Results of surgery are not as favourable as antiipated: 18% ardiovasular mortality and 35% remain hypertensive. 13 Ou P, Bonnet D, Auriaombe L, Pedroni E, et al. Late systemi hypertension and aorti arh geometry after suessful repair of oartation of the aorta. Eur Heart J 2004;25: MRI analysis of the aorti arh long after oartation repair and its orrelation with hypertension and inreased left ventriular mass. Despite adequate oartation repair, an autely angled aorti arh is assoiated with inreased blood pressure. 14 Bouhart F, Dubar A, Tabley A, et al. Coartation of the aorta in adults: surgial results and long-term follow-up. Ann Thora Surg 2000;70: Signifiant inidene of exerise indued hypertension after satisfatory repair of oartation when performed in adults. 15 O Sullivan JJ, Derrik G, Darnell R. Prevalene of hypertension in hildren after early repair of oartation of the aorta: a ohort study using asual and 24-hour blood pressure measurement. Heart 2002;88: Early onset of hypertension in hildren with good results from surgial repair need for long term follow up. 16 Oliver JM, Gallego P, Gonzalez A, et al. Risk fators for aorti ompliations in adults with oartation of the aorta. J Am Coll Cardiol 2004;44: Aneurysm inidene of 16% with two thirds in the asending aorta. Aneurysms ourred after surgery, atheter intervention, and in untreated patients. 17 Markham LW, Kneht SK, Daniels SR, et al. Development of exeriseindued arm-leg blood pressure gradient and abnormal arterial ompliane in patients with repaired oartation of the aorta. Am J Cardiol 2004;94: Patients with a satisfatory repair and normotension at rest an develop arm leg gradients up to 100 mm Hg. 18 Beauhesne L, Connolly H, Ammash N, et al. Coartation of the aorta: outome of pregnany. J Am Coll Cardiol 2001;38: Follow up of pregnanies in 50 women. Hypertension is ommon and related to oartation gradients while ardiovasular ompliations are infrequent. Fetal outome is good. Additional referenes appear on the Heart website Heart: first published as /hrt on 17 Otober Downloaded from on 21 July 2018 by guest. Proteted by opyright.