DOI: 10.1002/pd.4650
ORIGINAL ARTICLE
Pulmonary stenosis in complicated monochorionic twin pregnancies: prevalence, management and outcome V. Stagnati1,2,3, G. E. Chalouhi1,2*, M. Essaoui1,2, A. Giuseppi4, J. J. Stirnemann1,2, J. Le Bidois5 and Y. Ville1,2 1
National Referral Centre for Twin-to-Twin Transfusion Syndrome, Paris-Descartes University, Necker-Enfants-Malades Hospital, APHP, Paris, France Obstetrics and Fetal Medicine Department, Necker-Enfants-Malades Hospital, APHP, Paris V University, Paris, France 3 Maternal Fetal Medicine Unit, University of Brescia, Spedali Civili di Brescia, Brescia, Italy 4 Neonatology Department, Necker-Enfants-Malades Hospital, APHP, Paris V University, Paris, France 5 Pediatric Cardiology Department, Necker-Enfants-Malades Hospital, APHP, Paris V University, Paris, France *Correspondence to: G. E. Chalouhi. E-mail: [email protected] 2
ABSTRACT Objective To review prevalence, management and prognostic factors of pulmonary stenosis (PS) in monochorionic diamniotic (MCDA) pregnancies complicated by twin-to-twin transfusion syndrome (TTTS). Methods Retrospective study over the last 10 years in a single referral center. We reviewed fetal echocardiography data of all MC twin cases with diagnosis of isolated PS. We assessed fetoscopy characteristics of those that underwent laser coagulation. We collected data regarding perinatal outcome, neonatal echocardiography and cardiac management. Results We found 24 cases of isolated PS among 2091 MCDA pregnancies. Among 1052 complicated MCDA that underwent fetal laser surgery, 22 (2.09%) developed PS of which 20 were diagnosed prenatally. Two cases were diagnosed in uncomplicated MCDA pregnancies (0.2%). Four of 22 (18.18%) cases with TTTS showed in utero regression after laser treatment. Thirteen newborns (65%) required valvular dilatation. Peak systolic velocities in the pulmonary artery trunk (PSV-PA) at diagnosis and the interval between the diagnosis of TTTS and that of PS were significantly different (p < 0.001 and p = 0.05 respectively) between PS requiring cardiac intervention and those who did not.
Conclusion An elevated PSV-PA at the time of PS diagnosis and a short time-interval between fetoscopic laser surgery and PS diagnosis are predictive of the need for interventional treatment after birth. © 2015 John Wiley & Sons, Ltd.
Funding sources: None Conflicts of interest: None declared
INTRODUCTION Cardiac malformations are the most prevalent congenital defects in the general population. Their prevalence is increased up to tenfold in monochorionic (MC) twins. Severe twin-to-twin transfusion syndrome (TTTS) has been shown to be associated with a further threefold increase for congenital heart defects (CHD) compared to MC/DA twins from uncomplicated pregnancies. The most reported malformation is right ventricular outflow tract obstruction including pulmonary stenosis (PS) and pulmonary atresia with intact septum (PA-IS), which should be distinguished from the cardiomyopathy in the recipient characterized by myocardial hypertrophy and tricuspid regurgitation, without outflow tract obstruction, found in up to 65% of early TTTS stages.1,2 The pathophysiology of these malformations remains uncertain. It is believed to be caused by a hemodynamic malformative sequence secondary to both an abnormal intertwin placental circulation and an early increased Prenatal Diagnosis 2015, 35, 1085–1092
cardiac output in the recipient twin which is present in up to 50% of stage-1 cases.2,3 The signs of cardiac dysfunction in the recipient can be mild to severe in up to 70% of cases at time of diagnosis.4–6 It commonly encompasses cardiomegaly with biventricular hypertrophy, tricuspid and mitral regurgitation, systolic and diastolic dysfunction. In about half the cases, it is restricted to cardiomyopathy in the recipient where the myocardial muscle is thickened and the heart is enlarged, without neither ventricular dilatation nor pulmonary stenosis.7–9 Recent studies have shown that pulmonary stenosis/atresia is associated with this type of right ventricular systolic dysfunction.10,11 Our study aimed at determining the prevalence, time course of development and diagnosis of PS as well as its prognosis and postnatal management in a national reference center for both complicated monochorionic multiple pregnancies12 and congenital heart defects.13 © 2015 John Wiley & Sons, Ltd.
1086
METHODS All cases of monochorionic twin pregnancies that were referred for the suspicion of TTTS, severe selective intrauterine growth restriction (sIUGR) of one twin, twin anemia– polycythemia sequence (TAPS) or twin-reversed arterial perfusion sequence (TRAP) to a single referral center between 2003 and 2013 were reviewed. We searched for pre or postnatal diagnosis of pulmonary valve stenosis or pulmonary atresia with intact septum. Cases were identified from both the computerized ultrasound database (Astraia© software, obstetric and gynecological databases, version 1.21.1, Munich, Germany) and the neonatalcardiologic database. The two were cross-matched, and duplicates were deleted. As this was a retrospective audit of clinical data presented on anonymised data, no Institutional Review Board approval was requested. Pregnancies were dated according to crown rump length (CRL) of the largest twin (NICE Antenatal-care guidelines14). Chorionicity was assessed at 11–14 weeks in all cases. Following delivery, placentas were also routinely examined and mono-chorionicity was confirmed. Prenatal ultrasonographic follow-up was scheduled every 2 weeks in uncomplicated monochorionic twin pregnancies. Referred uncomplicated monochorionic twin pregnancies were seen once a week for 2 weeks until the diagnosis of a complication was excluded and then were referred back to their referring center. Complicated monochorionic twin pregnancies were followed weekly. After fetal laser therapy, follow-up scans were performed at the referral center for at least 3 weeks. Thereafter, follow-up scans were scheduled at the referring hospital only if the patient lived far from the referral center. All the referring hospitals were tertiary fetal medicine units certified for fetal ultrasound, care and treatment of MCDA. All cases with a suspicion of pulmonary stenosis or atresia at initial evaluation or at follow-up scans were referred for fetal echocardiography performed by an experienced perinatal cardiologist. The flow through the atrioventricular valves, the aortic and pulmonary valves and the ductus arteriosus were assessed by color, pulsed and continuous wave Doppler. Structural and functional cardiac features such as: tricuspid or mitral regurgitation, myocardial hypertrophy, pulmonary trunk peak velocity, pulmonary valve diameter, pulmonary branches sizes and ductus arteriosus flow direction were also recorded. PS was diagnosed in the presence of jet acceleration across the pulmonary valve, with or without the presence of thickened and domed pulmonary valve cusps associated to structural or functional right heart abnormalities (right ventricle hypertrophy, tricuspid regurgitation; dysplastic pulmonary valve; abnormal ductus venosus…). We chose the 95th centile of PSV-PA before 28 weeks as a cut-off for peak systolic velocity of the pulmonary artery (PSV-PA); according to the literature, this cut off is 0.9 m/s.15,16 Critical valvular stenosis or pulmonary atresia was diagnosed in case of reversed flow across the ductus arteriosus associated with a small or absent flow across the pulmonary valve respectively.17,18 Prenatal Diagnosis 2015, 35, 1085–1092
V. Stagnati et al.
Obstetrical and ultrasound characteristics including Doppler findings, amniotic fluid discrepancy, development of TTTS, severe sIUGR, TAPS, or TRAP sequence were reviewed. The diagnosis of TTTS was based on the ultrasound criteria used in the Eurofoetus trial,19 i.e. consisting of a polyuric polyhydramnios in the recipient twin with a deepest vertical pool of at least 8.0 cm at or before 20 weeks of gestation or 10.0 cm after 20 weeks of gestation together with a distended fetal bladder, coinciding with oliguric oligohydramnios in the donor twin, having a deepest vertical pool of at most 2.0 cm. Ultrasound staging of TTTS was done according to the Quintero staging system.20 TAPS was diagnosed when a discordance was found in the measurement of the peak systolic velocity in the middle cerebral artery (PSVMCA): PSV-MCA >1.5 multiple of the mean (MoM) in one twin (anemic) and PSV-MCA
ORIGINAL ARTICLE
Pulmonary stenosis in complicated monochorionic twin pregnancies: prevalence, management and outcome V. Stagnati1,2,3, G. E. Chalouhi1,2*, M. Essaoui1,2, A. Giuseppi4, J. J. Stirnemann1,2, J. Le Bidois5 and Y. Ville1,2 1
National Referral Centre for Twin-to-Twin Transfusion Syndrome, Paris-Descartes University, Necker-Enfants-Malades Hospital, APHP, Paris, France Obstetrics and Fetal Medicine Department, Necker-Enfants-Malades Hospital, APHP, Paris V University, Paris, France 3 Maternal Fetal Medicine Unit, University of Brescia, Spedali Civili di Brescia, Brescia, Italy 4 Neonatology Department, Necker-Enfants-Malades Hospital, APHP, Paris V University, Paris, France 5 Pediatric Cardiology Department, Necker-Enfants-Malades Hospital, APHP, Paris V University, Paris, France *Correspondence to: G. E. Chalouhi. E-mail: [email protected] 2
ABSTRACT Objective To review prevalence, management and prognostic factors of pulmonary stenosis (PS) in monochorionic diamniotic (MCDA) pregnancies complicated by twin-to-twin transfusion syndrome (TTTS). Methods Retrospective study over the last 10 years in a single referral center. We reviewed fetal echocardiography data of all MC twin cases with diagnosis of isolated PS. We assessed fetoscopy characteristics of those that underwent laser coagulation. We collected data regarding perinatal outcome, neonatal echocardiography and cardiac management. Results We found 24 cases of isolated PS among 2091 MCDA pregnancies. Among 1052 complicated MCDA that underwent fetal laser surgery, 22 (2.09%) developed PS of which 20 were diagnosed prenatally. Two cases were diagnosed in uncomplicated MCDA pregnancies (0.2%). Four of 22 (18.18%) cases with TTTS showed in utero regression after laser treatment. Thirteen newborns (65%) required valvular dilatation. Peak systolic velocities in the pulmonary artery trunk (PSV-PA) at diagnosis and the interval between the diagnosis of TTTS and that of PS were significantly different (p < 0.001 and p = 0.05 respectively) between PS requiring cardiac intervention and those who did not.
Conclusion An elevated PSV-PA at the time of PS diagnosis and a short time-interval between fetoscopic laser surgery and PS diagnosis are predictive of the need for interventional treatment after birth. © 2015 John Wiley & Sons, Ltd.
Funding sources: None Conflicts of interest: None declared
INTRODUCTION Cardiac malformations are the most prevalent congenital defects in the general population. Their prevalence is increased up to tenfold in monochorionic (MC) twins. Severe twin-to-twin transfusion syndrome (TTTS) has been shown to be associated with a further threefold increase for congenital heart defects (CHD) compared to MC/DA twins from uncomplicated pregnancies. The most reported malformation is right ventricular outflow tract obstruction including pulmonary stenosis (PS) and pulmonary atresia with intact septum (PA-IS), which should be distinguished from the cardiomyopathy in the recipient characterized by myocardial hypertrophy and tricuspid regurgitation, without outflow tract obstruction, found in up to 65% of early TTTS stages.1,2 The pathophysiology of these malformations remains uncertain. It is believed to be caused by a hemodynamic malformative sequence secondary to both an abnormal intertwin placental circulation and an early increased Prenatal Diagnosis 2015, 35, 1085–1092
cardiac output in the recipient twin which is present in up to 50% of stage-1 cases.2,3 The signs of cardiac dysfunction in the recipient can be mild to severe in up to 70% of cases at time of diagnosis.4–6 It commonly encompasses cardiomegaly with biventricular hypertrophy, tricuspid and mitral regurgitation, systolic and diastolic dysfunction. In about half the cases, it is restricted to cardiomyopathy in the recipient where the myocardial muscle is thickened and the heart is enlarged, without neither ventricular dilatation nor pulmonary stenosis.7–9 Recent studies have shown that pulmonary stenosis/atresia is associated with this type of right ventricular systolic dysfunction.10,11 Our study aimed at determining the prevalence, time course of development and diagnosis of PS as well as its prognosis and postnatal management in a national reference center for both complicated monochorionic multiple pregnancies12 and congenital heart defects.13 © 2015 John Wiley & Sons, Ltd.
1086
METHODS All cases of monochorionic twin pregnancies that were referred for the suspicion of TTTS, severe selective intrauterine growth restriction (sIUGR) of one twin, twin anemia– polycythemia sequence (TAPS) or twin-reversed arterial perfusion sequence (TRAP) to a single referral center between 2003 and 2013 were reviewed. We searched for pre or postnatal diagnosis of pulmonary valve stenosis or pulmonary atresia with intact septum. Cases were identified from both the computerized ultrasound database (Astraia© software, obstetric and gynecological databases, version 1.21.1, Munich, Germany) and the neonatalcardiologic database. The two were cross-matched, and duplicates were deleted. As this was a retrospective audit of clinical data presented on anonymised data, no Institutional Review Board approval was requested. Pregnancies were dated according to crown rump length (CRL) of the largest twin (NICE Antenatal-care guidelines14). Chorionicity was assessed at 11–14 weeks in all cases. Following delivery, placentas were also routinely examined and mono-chorionicity was confirmed. Prenatal ultrasonographic follow-up was scheduled every 2 weeks in uncomplicated monochorionic twin pregnancies. Referred uncomplicated monochorionic twin pregnancies were seen once a week for 2 weeks until the diagnosis of a complication was excluded and then were referred back to their referring center. Complicated monochorionic twin pregnancies were followed weekly. After fetal laser therapy, follow-up scans were performed at the referral center for at least 3 weeks. Thereafter, follow-up scans were scheduled at the referring hospital only if the patient lived far from the referral center. All the referring hospitals were tertiary fetal medicine units certified for fetal ultrasound, care and treatment of MCDA. All cases with a suspicion of pulmonary stenosis or atresia at initial evaluation or at follow-up scans were referred for fetal echocardiography performed by an experienced perinatal cardiologist. The flow through the atrioventricular valves, the aortic and pulmonary valves and the ductus arteriosus were assessed by color, pulsed and continuous wave Doppler. Structural and functional cardiac features such as: tricuspid or mitral regurgitation, myocardial hypertrophy, pulmonary trunk peak velocity, pulmonary valve diameter, pulmonary branches sizes and ductus arteriosus flow direction were also recorded. PS was diagnosed in the presence of jet acceleration across the pulmonary valve, with or without the presence of thickened and domed pulmonary valve cusps associated to structural or functional right heart abnormalities (right ventricle hypertrophy, tricuspid regurgitation; dysplastic pulmonary valve; abnormal ductus venosus…). We chose the 95th centile of PSV-PA before 28 weeks as a cut-off for peak systolic velocity of the pulmonary artery (PSV-PA); according to the literature, this cut off is 0.9 m/s.15,16 Critical valvular stenosis or pulmonary atresia was diagnosed in case of reversed flow across the ductus arteriosus associated with a small or absent flow across the pulmonary valve respectively.17,18 Prenatal Diagnosis 2015, 35, 1085–1092
V. Stagnati et al.
Obstetrical and ultrasound characteristics including Doppler findings, amniotic fluid discrepancy, development of TTTS, severe sIUGR, TAPS, or TRAP sequence were reviewed. The diagnosis of TTTS was based on the ultrasound criteria used in the Eurofoetus trial,19 i.e. consisting of a polyuric polyhydramnios in the recipient twin with a deepest vertical pool of at least 8.0 cm at or before 20 weeks of gestation or 10.0 cm after 20 weeks of gestation together with a distended fetal bladder, coinciding with oliguric oligohydramnios in the donor twin, having a deepest vertical pool of at most 2.0 cm. Ultrasound staging of TTTS was done according to the Quintero staging system.20 TAPS was diagnosed when a discordance was found in the measurement of the peak systolic velocity in the middle cerebral artery (PSVMCA): PSV-MCA >1.5 multiple of the mean (MoM) in one twin (anemic) and PSV-MCA
