CC BY-NC-ND 4.0 · AJP Rep 2019; 09(02): e121-e126
DOI: 10.1055/s-0038-1677480
Case Report
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Prenatal Diagnosis and Successful Palliation of Absent Aortic Valve with Hypoplastic Left Heart Syndrome: A Case Report and Review of Literature

1  Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas
,
Chelsea B. Johnson
1  Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas
,
Muhammad A. Aly
1  Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas
,
2  Division of Pediatric Cardiology, University of Texas Medical Branch, Galveston, Texas
› Author Affiliations
Further Information

Address for correspondence

Amna Qasim, MD
Department of Pediatrics, University of Texas Medical Branch
301 University Boulevard, Galveston
TX-77555   

Publication History

12 September 2018

02 December 2018

Publication Date:
09 April 2019 (online)

 

Abstract

Introduction Congenital absence of the aortic valve leaflets is a rare association with hypoplastic left heart syndrome (HLHS).

Case A 37-year-old pregnant woman was referred for fetal evaluation of possible HLHS at 22 weeks of gestation. The fetal echocardiogram (ECHO) was remarkable for a hypoplastic left atrium, nearly atretic mitral valve, small left ventricle, and a hypoplastic aortic valve with severe aortic insufficiency. A female infant was born at term and postnatal ECHO confirmed the above findings. In addition, there was complete absence of the aortic valve leaflets. The patient underwent Norwood's procedure at day 5 of life with atrial septectomy, over-sewing of the aortic valve annulus, and a 4 mm Sano's shunt between the right ventricle and the main pulmonary artery. She tolerated this surgery well and subsequently underwent a bidirectional Glenn's procedure at 8 months of life.

Conclusion Prenatal diagnosis of absent aortic valve should be suspected in the presence of severe aortic insufficiency in the fetal ECHO. Early postnatal intervention is critical as those patients are likely to deteriorate quickly. The over-sewing of the aortic valve may be important to prevent coronary steal and myocardial hypoperfusion which could potentially be detrimental.


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Absence of the aortic valve (AAV) is a very rare congenital heart defect, unlike the absence of pulmonary valves. AAV is usually associated with other cardiac and non-cardiac anomalies. Most of the previously reported cases have been in spontaneously aborted fetuses, underscoring the high mortality of this heart defect.

Case

A 37-year-old pregnant female (Gravida 5, Para 3) was referred for fetal echocardiogram (ECHO) due to concerns of hypoplastic left heart (HLH) on anatomy ultrasound scan. Fetal ECHO at 22 weeks was significant for a hypoplastic left atrium, nearly atretic mitral valve, small nonapex forming left ventricle (LV), hypoplastic aortic valve with severe aortic insufficiency ([Fig. 1]). Serial fetal ECHOs showed the same findings throughout pregnancy. No evidence of hydrops was seen. At 39-week gestation, a female infant was delivered with a birth weight 3.2 kg and Apgar's scores of 8 and 8 at 1 and 5 minutes, respectively. Prostaglandin E-1 (0.05 mcg/kg/min) infusion was started within an hour of delivery. Postnatal ECHO findings ([Fig. 2], [Video 1]) showed HLH variant with absent aortic valve and severe aortic insufficiency, a large PDA, moderate sized atrial septal defect (ASD), and poor left ventricular posterior wall function. The LV was diffusely echogenic but there was no clear endocardial fibro elastosis. There was decimal mitral inflow and a mild tricuspid valve insufficiency. The right ventricle was globular with a normal function. The coronary anatomy was normal but the flow was difficult to assess. Since the patient had no dysmorphic features or any extra cardiac anomaly, no genetic testing was done. The patient successfully underwent the first stage Norwood's procedure on the 5th day of life. The procedure included atrial septectomy, an end to side main pulmonary artery to aorta (Damus-Kaye-Stansel) anastamosis, PDA ligation, over-sewing of the aortic valve, and the placement of a 4 mm Sano's shunt between the right ventricle and the main pulmonary artery. Subsequently, she underwent the bidirectional Glenn's procedure at 8 months of life and is currently doing well and maintaining her O2 saturations in the mid-80s on room air.

Video 1

A parasternal long axis view showing a hypoplastic left ventricle and an absent aortic valve with severe regurgitation.


Quality:
Zoom Image
Fig. 1 Fetal ECHO “4-chamber view” showing a hypoplastic left ventricle and left atrium (left) and color Doppler's image showing aortic regurgitation (right).
Zoom Image
Fig. 2 Postnatal ECHO showing a hypoplastic left ventricle seen in 4-chamber view (left) and aortic regurgitation seen in parasternal long axis view (right).

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Discussion

Absent aortic valve (AAV) is a rare congenital heart defect with our case being the 26th that was reported in literature.[1] It is usually associated with other congenital anomalies including HLH, double outlet right ventricle (DORV), mitral atresia and absent, or dysplastic pulmonary valve. The clinical presentation may vary but mainly includes cyanosis, respiratory distress and cardiomegaly in the majority of reported cases. [Table 1] shows a review of previously reported cases to date. The rarity of this condition may be due to the high rate of mortality leading to spontaneous abortions. Even though it was initially thought to be an X-linked recessive condition due to the first few reports being males, that does not seem to be the case since a few female cases have been reported.

Table 1

Summary of all reported cases with absent aortic valves

Case no., gender

Diagnosis age and method

Other CHD

Noncardiac anomalies

Clinical presentation

Outcome

Ref.

1, M

36 h, autopsy

DORV, enlarged RA and RV, ASD, PDA, dysplastic LV, hypoplastic MV and LV

Accessory spleen

Severe cyanosis and cardiomegaly at 36 h

Death at 2 d

[7]

2, M

32 wk, fetal ECHO + autopsy

DORV, common AV canal, hypoplastic MV and LV

Absent R SVC, anomalous L SVC, splenic nodules, gut malrotation

Hydrops, severe polyhydramnios, RD

Death at 20 h

[8]

3, M

24 h, ECHO + autopsy

Hypoplastic MV and LV, EFE of LV

None

Cyanosis, RD, tachycardia

Death at 8 d

[9]

4, M

4 h, ECHO + autopsy

Hypoplastic LA, EFE of LV, anomalous RSA, dysplastic TV and PV, PDA

3 lobes in left lung and horseshoe kidneys

Severe cyanosis and RD

Death at 4 d

[10]

5, F

1 d, autopsy

ASD, VSD, Interrupted aortic arch, anomalous RSA

DiGeorge's syndrome (absent thymus, PTH glands)

RD, cardiomegaly

Death at 36 h

[11]

6, M

12 h, ECHO + autopsy

MV atresia, Dysplastic PV, PDA, normal LV

ND

RD, cyanosis

Death at 24 h

[12]

7, M

11 h, ECHO + autopsy

Dysplastic MV, PDA

ND

Cyanosis, RDS

Death at 16 h

[13]

8, M

20 h, autopsy

Dysplastic MV, PV stenosis, LV EFE

Cortical renal cysts, hydroureter/nephrosis, microcephaly

Cyanosis, RD, cardiomegaly

Death at 20 h

[14]

9, M

24 h, autopsy

Hypoplastic LA and LV, LV EFE, ASD, PDA

Hemosiderosis of liver, minimal deposits in kidney and spleen

RD, cyanosis

Death at 24 h

[14]

10, M

4 d, echo

MV atresia, Ebstein malformation, TAPVR, PDA

Hemosiderosis of liver

Cyanosis

Death at 6 d

[14]

11, F

18 wk, autopsy

DORV, HLV, VSD, straddling of TV, MV atresia, absent PV

Hypoplastic nose, radial aplasia, absent thumbs, absent left index finger, intestinal malrotation, horseshoe kidney

Spontaneous abortion, severely macerated fetus

IUD at 18 wk

[15]

12, M

18 wk, autopsy

Absent PV, VSD, small MV, thickened LV

Cleft lip/palate, low set ears

Spontaneous abortion, severely macerated fetus

IUD at 18 wk

[15]

13, F

18 wk, autopsy

Complete AVSD, persistent LSVC, anomalous RSA

Nuchal bleb, edema, thymic hypoplasia, Trisomy 13 on cytogenetics

Generalized edema

Abortion at 18 wk

[16]

14, F

14 wk, autopsy

DORV, VSD, absent PV, MV atresia, hypoplastic LA

Cystic hygroma, umbilical herniation, single UA, thymic hypoplasia

Artificial abortion at 14 wk

[16]

15, M

21 wk, autopsy

DORV, VSD, absent PV

Cystic hygroma, single UA, absent thymus

Generalized edema

Artificial abortion at 21 wk

[16]

16, ND

17 wk, fetal ECHO + autopsy

DORV, HLV, VSD, PDA

Hydranencephaly, hypoplastic left forearm, right radial aplasia

Hydrops, pericardial effusion, cardiomegaly

Termination at 18 wk

[17]

17, M

9 h, 2D ECHO

VSD, patent LSVC, absent MV, PDA, EFE of LV

High-arched palate, low set ears

Heart failure, cyanosis

Death at 20 h

[18]

18, M

12 h, ECHO + cath

HLH, EFE of LV, dysplastic MV

ND

Cyanosis, cardiomegaly

Norwood's + BT shunt at 7 dol, death at 20 dol

[19]

19, M

ND, ECHO

Dysplastic LV, MV atresia, PDA

None

Mild cyanosis

Norwood's at 12 dol, heart transplant at 1.5 mo

[3]

20, M

Fetal ECHO at 29 wk

VSD, PDA, dysplastic PV

ND

Fetal hydrops

Death at 4 h

[20]

21, M

2 d, ECHO

MV atresia

ND

Cyanosis, Respiratory distress

Norwood's at 9 d, BDG at 6 mo, Fontan's at 6 y

[2] [21]

22, ND

31 wk, Fetal ECHO

LV hypertrophy and EFE

Generalized lymphangiectasis, systemic air embolism

Fetal hydrops

Death at 2 h

[22]

23, F

24 wk, Fetal ECHO

DORV, large VSD, left SVC, AP window

Cystic hygroma, cerebral ventriculomegaly, microcephaly, clinodactyly, bilateral ear dysplasia, choanal atresia

Respiratory depression

Death at 2 d

[23]

24, M

24 wk, Fetal ECHO

HLH, MV atresia

Broad fingers

Cardiomegaly, cyanosis

Norwood's and BDG at 3 mo, death at 10 mo

[1]

25, M

23 wk, Fetal ECHO

Dilated LV, EFE, hypoplastic MV

ND

Fetal hydrops

IUD at 28 w

[1]

Abbreviations: AAV, absent aortic valve; AP, aorticopulmonary; ASD, atrial septal defect; AV, atrioventricular; AVSD, atrioventricular septal defect; BDG, bi-directional Glenn; CHD, congenital heart disease; d, day; dol, day of life; DORV, double outlet right ventricle; ECHO, echocardiogram; EFE, endocardial fibroelastosis; F, female; h, hour; HLH, hypoplastic left heart; HLV, hypoplastic left ventricle; IUD, intrauterine demise; L, left; LV, left ventricle; M, male, mo, months; MV, mitral valve; ND, not described; PDA, patent ductus arteriosus; PTH, parathyroid glands; PV, pulmonary valve; R, right; RA, right atrium; RD, respiratory distress; RSA, right subclavian artery; RV, right ventricle; SVC, superior vena cava; TAPVR, total anomalous pulmonary venous return; TV, tricuspid valve; UA, umbilical artery; wk, week; y, year.


Only two reported cases have survived beyond the first few days of life. Harada et al[2] described the first case of successful palliative surgery in a patient with HLH syndrome and AAV. At 9 days of life, the patient underwent Norwood's procedure with a Blalock–Taussig (BT) shunt. The aortic valve was noted to be absent and left ventricular cavity size was small with endocardial fibroelastosis. The patient did well and underwent the bidirectional Glenn's procedure at the age of 6 months and the Fontan's procedure at the age of 6 years. The aortic annulus was not over-sewn with the thought that coronary circulation would be maintained owing to the markedly diminished size and compliance of the LV. In addition, a balloon occlusion of the left ventricular outflow tract showed no effect on the coronary circulation.

The second case of AAV that survived beyond the first few days of life was reported by Krasemann et al.[3] Associated cardiac defects included mitral atresia and a large noncontractile hypoplastic LV. On day 12 of life the infant underwent the Norwood's procedure with additional surgical closure of the aortic valve with the goal of preservation of coronary perfusion. The postoperative course was complicated by difficulty weaning from mechanical ventilation. An orthotropic heart transplantation was successfully performed 4 weeks after the Norwood's procedure. The postoperative course was uneventful. The child was doing well at 5 months of age when this case was reported.

The majority of reported cases of AAV were diagnosed either on autopsy or on postnatal ECHO, with only a handful of cases diagnosed on fetal ECHO ([Table 1]). Fetal ECHO was introduced as a diagnostic modality in the early 1970s and has advanced significantly over the past few decades.[4] It has been shown to be a valuable tool in the optimization of perinatal care.[5] [6] To date, no fetal interventions have been attempted for the palliation of this condition.

Our case is one of the first few reported cases that were diagnosed by fetal ECHO, the second case that underwent successful palliative repair, and the third case that survived beyond the first few days of life. To our knowledge, it is also the first reported case in which the infant underwent successful Norwood's procedure with closure of the aortic valve annulus. Closure of the aortic valve annulus would prevent the development of coronary steal syndrome that may occur if continued aortic regurgitation leads to increased left ventricular size and compliance.


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Conclusion

AAV is rare and is usually associated with other congenital cardiac anomalies, especially HLHS. It should be suspected in the presence of aortic insufficiency on fetal ECHO. Palliative repair with Norwood's procedure with over-sewing of the aortic annulus could potentially prevent coronary steal and myocardial hypoperfusion in these patients.


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Conflict of Interest

The authors declare that they have no conflicts of interest.

Ethical Approval

This article does not contain any studies with human participants performed by any of the authors.


Informed Consent

Informed consent was waived for this study since no identifying information was included.



Address for correspondence

Amna Qasim, MD
Department of Pediatrics, University of Texas Medical Branch
301 University Boulevard, Galveston
TX-77555   


  
Zoom Image
Fig. 1 Fetal ECHO “4-chamber view” showing a hypoplastic left ventricle and left atrium (left) and color Doppler's image showing aortic regurgitation (right).
Zoom Image
Fig. 2 Postnatal ECHO showing a hypoplastic left ventricle seen in 4-chamber view (left) and aortic regurgitation seen in parasternal long axis view (right).