Atretic Coronary Artery Ostia in a Full-Term Infant with Early Postnatal Demise

Abstract

Congenital coronary artery anomalies are extremely rare causes of early cardiac failure. Several cardiac lesions are associated with coronary anomalies such as pulmonary atresia with intact ventricular septum. Isolated coronary ostial atresia is extremely rare and described in only a few published case reports. To our knowledge, there were two reports of bilateral coronary ostial atresia in which the entire coronary arterial system originated from the right ventricle without other intracardiac defects. We present a case of a full-term infant who presented with severely depressed biventricular function secondary to bilateral coronary ostial atresia.

Case

Our patient was born at an outside hospital at 39 weeks' gestation via scheduled cesarean section. Her birth weight was 3,600 g. The pregnancy was notable for triple X syndrome on noninvasive prenatal testing, and further genetic work-up was recommended to determine if this was maternal, fetal, or placental. Prenatal maternal laboratory serologies were unremarkable and the pregnancy was otherwise uncomplicated.

The patient's initial Apgar scores were 8 and 8 at 1 and 5 minutes of life, respectively. In the delivery room, she was persistently cyanotic requiring positive pressure ventilation and then continuous positive airway pressure with persistent peripheral capillary oxygen saturation of 70 to 80% on 100% fraction of inspired oxygen (FiO ₂ ). A chest X-ray showed cardiomegaly with possible respiratory distress syndrome. She was intubated for respiratory failure and administered surfactant. A limited echocardiogram demonstrated poor biventricular function (left ventricular ejection fraction of 24%), a small patent ductus arteriosus, and a patent foramen ovale with bidirectional flow. The remainder of her initial work-up was notable only for thrombocytopenia (platelets of 50–60 × 10 ³ /mm ³ ).

The patient was transferred to our institution's infant cardiac unit by 15 hours of life (HOL). She had a soft systolic ejection murmur at the middle to lower left sternal border. Her electrocardiogram showed a normal sinus rhythm with intermittent premature ventricular complexes, a northwest axis, and a right bundle branch block. Her initial troponin was elevated at 0.7 ng/mL.

A repeat echocardiogram showed normal segmental anatomy, confirmed that her biventricular function was severely decreased, and showed two small atrial communications with left-to-right shunting. Most notably, there were no coronary arteries noted to be originating from the aorta wherein the left coronary artery system appeared prominent and slightly dilated coursing near but not arising from the aorta based on color flow imaging ( Fig. 1 ). Bidirectional flow was seen in the left coronary artery system and there was suggestion of connection to the right ventricular outflow tract (RVOT). The right coronary artery was not visualized in two-dimensional or on color imaging.

Fig. 1.

The coronary fistula and left coronary system as demonstrated on echocardiography. ( A ) A modified apical view angled anteriorly toward the RVOT shows the coronary fistula arising from just below the pulmonary valve. ( B ) A modified parasternal short axis view angled slightly superiorly shows the coronary fistula adjacent to the PA. The left coronary system courses near the aorta but does not fill from the aorta with the Doppler color flow showing retrograde flow within the left coronary system. Ao, aorta; PA, pulmonary artery; RV, right ventricle; RVOT, right ventricular outflow tract.

With concern for bilateral coronary ostial atresia and worsening myocardial ischemia with an increasing troponin of 1.9 ng/mL at 21 HOL, the patient urgently underwent a diagnostic right and left heart catheterization. The aortic root angiograms showed no coronary arteries arising from the aorta ( Fig. 2 ). However, the RVOT angiogram demonstrated flow into the left anterior descending and circumflex arteries arising from the RVOT immediately inferior to the pulmonary valve ( Fig. 3 ). Again, no right coronary artery was identified. The right ventricular (RV) pressure during catheterization was 34/11 mm Hg.

Fig. 2.

Angiogram with a pigtail catheter in the ascending aorta demonstrating the absence of coronary arteries arising from the aorta. ( A ) Anterior–posterior projection. ( B ) Lateral projection.

Fig. 3.

Angiogram with a Berman catheter in the RVOT demonstrating coronary vessels (solid white arrow) arising from the distal outflow tract. ( A ) Anterior–posterior projection. ( B ) Lateral projection. RVOT, right ventricular outflow tract.

After establishing the diagnosis of bilateral coronary ostial atresia, further management options were discussed among a multidisciplinary team. During this time, the patient remained intubated on an FiO ₂ of 45%, with rising troponins (peak troponin of 4.11 ng/mL at 32 HOL), and dobutamine of 5 µg/kg/min, but remained hemodynamically stable. Due to her poor expected clinical trajectory, the team discussed of all the possible management options with the family including palliative care.

Strategies to maintain high RV pressure to maintain coronary perfusion in an effort to delay an arrest were discussed including main pulmonary artery (MPA) banding and initiating prostaglandin E (PGE) to enlarge the ductus arteriosus. However, neither of these options was pursued due to significantly elevated risks and marginal effectiveness. MPA banding in the setting of a RV with already severely decreased function was not favored. PGE was also not used because, while it would enlarge the ductus arteriosus and raise the pulmonary arterial pressure, it would also have the effect of lowering the pulmonary vascular resistance and was thought it would not likely have an overall positive effect.

The possibility of coronary surgical intervention was also discussed with our surgeons. As the left coronary artery ran adjacent to the aortic root, direct anastomosis of the coronary to the aorta may have been possible. However, given the complex distal coronary anatomy and fistulous connection to the RV, as well as the unknown information about the location or presence of the right coronary artery system, this was considered unfeasible.

Based on the patient's anatomy, the multidisciplinary team concluded that cardiac transplantation would offer the best opportunity for long-term survival. We considered two strategies to bridge her to transplantation. The first was to preemptively utilize extracorporeal membrane oxygenation (ECMO) followed by bi-ventricular assist devices (VADs) or bi-VAD alone prior to arrest as a bridge to transplantation. The second strategy was to observe closely until she experienced hemodynamic deterioration at which point ECMO would be initiated with subsequent conversion to VAD. The first approach would eliminate the morbidities associated with cardiopulmonary resuscitation, while the second would limit the length of exposure to the morbidities associated with ECMO and VAD. Both of these options were discussed with the family as well as the significant risk of neurological injury in infants on ECMO ¹ and VAD, ² in addition to other multisystem end-organ complications that can occur.

Additionally, the neonatal palliative care team was consulted early in the infant's course secondary to the tenuous nature of the diagnosis and uncertainty of the parent's wishes for their infant. The parents were presented with various options from the palliative team, including the option to forego any further work-up or treatment and optimize comfort for the neonate in light of the potentially catastrophic complications that could ensue from a cardiac arrest event.

After these discussions, the patient's parents were uncertain about their wishes regarding their goals of care and needed more time to process the information. On day of life 1 at ∼40 HOL, the patient was acutely decompensated with profound hypotension, bradycardia, and oxygen desaturation leading to a pulseless electrical activity arrest. Despite cardiorespiratory resuscitation for 45 minutes, she failed to have return of spontaneous circulation and her blood gases continued to show a significant lactic acidosis. Our ECMO team was activated at the initiation of the resuscitation as the parents had not expressed a desire to de-escalate care. However, after another discussion with the family considering her current clinical status, the family chose to stop the resuscitation and the patient passed away.

Discussion

Herein, we described a patient with bilateral coronary ostial atresia. To our knowledge, this is only the third case report published of this disease variant. ^{3 4} There are some similarities between the three cases as well as notable differences. As previously described in the case by Olabiyi et al, the entire coronary arterial system was only seen in communication with the RVOT. ³ Interestingly, our patient's right coronary system was never identified on echocardiogram or catheterization with only small collateralization noted in that region. However, the connection of the left coronary system to the right ventricle was in a very similar location in both cases, immediately inferior to the pulmonary valve.

In patients with pulmonary atresia and intact ventricular septum with RV-dependent coronary circulation, decompression of the right ventricle must be avoided to prevent severe myocardial infarction. ⁵ Similarly, our patient likely developed rapid myocardial ischemia secondary to natural decompression of the right ventricle related to a rapid decrease in pulmonary arterial pressure and pulmonary vascular resistance in the early postnatal period. The case published by Olabiyi et al reported that the ex-30-week gestation patient survived to day 21 of life, while the case by Wein et al reported a full-term infant who had a rapid clinical decline leading to early cardiac arrest. Similarly, our patient experienced rapid cardiac decompensation resulting in early cardiac arrest at 40 HOL. We attribute this difference in clinical decompensation to the more mature gestational age of the patient and the more rapid decline in pulmonary vascular resistance, our patient likely experienced. For our patient, born at 30 weeks with a very similar condition, the clinical decompensation may have been prolonged as the pulmonary vascular in premature infants declines more gradually.

Our experience outlines potential interventions from a multidisciplinary approach for this rare disease that may be diagnosed postnatally with rapid decompensation. No interventions were thought to be able to assist in maintaining high RV pressures. Surgical coronary reimplantation was not a feasible option given the complex left coronary artery system anatomy and unknown presence or location of the right coronary artery system. The use of ECMO and VAD support as a bridge to cardiac transplantation, either prior to or at the time of cardiac arrest, was thought to be the most effective management strategies. For future patients with this rare disease, early diagnosis and discussion of the use of ECMO and VAD as a bridge to transplant with the family are of utmost importance.

Finally, our study highlighted the potentially rapid progression of this disease and the critical importance of establishing goals of care in an early and a comprehensive management paradigm that accommodates sudden changes in clinical course. From our experience, we hope to emphasize the importance of early management of patients with bilateral coronary atresia and potential interventions to be implemented for similar patients in the future.