Anomalous right coronary artery from the pulmonary artery
- Philips Australia, Paid speaker at Philips Spectral CT events (ongoing)
Updates to Article Attributes
Anomalous right coronary artery from the pulmonary artery (ARCAPA), is a rare congenital coronary artery anomaly and is considered one of the most severe of such anomalies.
Epidemiology
This abnormality only accounts for less than 0.1% of all congenital cardiac anomalies 1 and is up to four times less prevalent than anomalous left coronary artery from the pulmonary artery (ALCAPA). There is a slight male predominance.
Associations
ARCAPA may be associated with a range of other cardiac abnormalities 1, most commonly an aortopulmonary septal defect (also known surgically as aortopulmonary window) which is seen in 10 % of cases.
Other associations include (in decreasing order of frequency) 1:
Clinical presentation
Patients may range from being completely asymptomatic with or without a murmur to presenting with sudden cardiac death.Patients are more likely to present later in life compared with those with ALCAPA. In a review of 223 patients in 193 papers 1, 38% were asymptomatic at the time of diagnosis. The and the median age at diagnosis was 14 years with a bimodal age distribution at < 1 year and 40 to 60 years. Almost 50% of patients had a murmur at the time of diagnosis.
Pathology
ALCAPA refers to a cardiovascular anomaly where the right main coronary artery arises from the pulmonary trunk instead of the left coronary sinus of the ascending aorta.
Aetiology
Either of two aetiologies can be responsible for ALCAPA:
the bulbus cordis undergoes abnormal septation into the aorta and pulmonary trunkpersistence of the pulmonary buds with concomitant involution of the aortic buds that are precursors of the coronary arteries
Pathophysiology
During the first month of life, physiologic pulmonary hypertension tends to preserve antegrade blood flow within the left coronary artery, and infants usually remain asymptomatic. Shortly thereafter, pulmonary artery pressure, resistance, and oxygen content decrease. Thus, the left ventricle receives blood with low oxygen content at low pressure, causing myocardial ischaemia. Further increases in myocardial oxygen consumption lead to infarction of the anterolateral left ventricular free wall, often with resultant mitral valve insufficiency in approximately 80-85% of cases (infantile type).
In 10-15% of patients, however, these events stimulate the development of collateral circulation via the right coronary artery to the anomalous left coronary circulation, thus these patients can reach adulthood The aetiology is not well understood. The disease most commonly manifestspathophysiology is similar to that seen in ALCAPA is the result of left ventricular dysfunction in combination with significant mitral insufficiency.
Radiographic features
Cardiac CT
ECG-gated cardiac CT allows direct visualisation of anomalous leftright main coronary arterial origin from the posterior aspect of the pulmonary artery. The left coronary artery may be unusually dilated and tortuous with evidence of collateral formation. Intercoronary collateral arteries along the external surface of the heart or within the interventricular septum may also be seen.
Treatment and prognosis
TBASurgical treatment aims to prevent coronary steal and restore the normal anatomic origin of the RCA 1. The RCA origin can either be re-implanted onto the aorta or ligated then bypassed with an arterial or venous graft. The surgery is often performed with cardiopulmonary bypass.
See also
-<p><strong>Anomalous right coronary artery from the pulmonary artery (ARCAPA)</strong>, is a rare <a href="/articles/congenital-coronary-artery-anomalies">congenital coronary artery anomaly</a> and is considered one of the most severe of such anomalies.</p><h4><strong>Epidemiology</strong></h4><p>This abnormality only accounts for less than 0.1% of all <a href="/articles/congenital-cardiovascular-anomalies">congenital cardiac anomalies</a> <sup>1</sup> and is up to four times less prevalent than <a href="/articles/anomalous-left-coronary-artery-from-the-pulmonary-artery" title="Anomalous left coronary artery from the pulmonary artery">anomalous left coronary artery from the pulmonary artery (ALCAPA)</a>. There is a slight male predominance.</p><h4><strong>Clinical presentation</strong></h4><p>Patients may range from being completely asymptomatic with or without a murmur to presenting with sudden cardiac death. Patients are more likely to present later in life compared with those with ALCAPA. In a review of 223 patients in 193 papers <sup>1</sup>, 38% were asymptomatic at the time of diagnosis. The median age at diagnosis was 14 years. Almost 50% of patients had a murmur at the time of diagnosis.</p><h4><strong>Pathology</strong></h4><p>ALCAPA refers to a cardiovascular anomaly where the <a href="/articles/right-main-coronary-artery" title="right main coronary artery">right main coronary artery</a> arises from the <a href="/articles/pulmonary-trunk">pulmonary trunk</a> instead of the left coronary sinus of the <a href="/articles/ascending-aorta">ascending aorta</a>.</p><h5><strong>Aetiology</strong></h5><p>Either of two aetiologies can be responsible for ALCAPA:</p><ul>-<li><p>the bulbus cordis undergoes abnormal septation into the aorta and pulmonary trunk</p></li>-<li><p>persistence of the pulmonary buds with concomitant involution of the aortic buds that are precursors of the coronary arteries</p></li>-</ul><h5><strong>Pathophysiology</strong></h5><p>During the first month of life, physiologic pulmonary hypertension tends to preserve antegrade blood flow within the left coronary artery, and infants usually remain asymptomatic. Shortly thereafter, pulmonary artery pressure, resistance, and oxygen content decrease. Thus, the left ventricle receives blood with low oxygen content at low pressure, causing myocardial ischaemia. Further increases in myocardial oxygen consumption lead to infarction of the anterolateral left ventricular free wall, often with resultant mitral valve insufficiency in approximately 80-85% of cases (infantile type).</p><p>In 10-15% of patients, however, these events stimulate the development of collateral circulation via the right coronary artery to the anomalous left coronary circulation, thus these patients can reach adulthood. The disease most commonly manifests in adulthood as late-onset rhythm disorders due to altered cardiac electric currents. Diminished pulmonary vascular resistance results in flow reversal in the left coronary artery into the pulmonary trunk (i.e. coronary steal phenomenon). <a href="/articles/congestive-cardiac-failure">Congestive heart failure (CHF)</a> is the result of left ventricular dysfunction in combination with significant mitral insufficiency.</p><h4><strong>Radiographic features</strong></h4><h5><strong>Cardiac CT</strong></h5><p>ECG-gated cardiac CT allows direct visualisation of anomalous left main coronary arterial origin from the posterior aspect of the pulmonary artery. The <a href="/articles/right-coronary-artery">right coronary artery</a> may be unusually dilated and tortuous with evidence of collateral formation. Intercoronary collateral arteries along the external surface of the heart or within the interventricular septum may also be seen.</p><h4><strong>Treatment and prognosis</strong></h4><p>TBA</p><h4><strong>See also</strong></h4><ul>- +<p><strong>Anomalous right coronary artery from the pulmonary artery (ARCAPA)</strong>, is a rare <a href="/articles/congenital-coronary-artery-anomalies">congenital coronary artery anomaly</a> and is considered one of the most severe of such anomalies.</p><h4><strong>Epidemiology</strong></h4><p>This abnormality only accounts for less than 0.1% of all <a href="/articles/congenital-cardiovascular-anomalies">congenital cardiac anomalies</a> <sup>1</sup> and is up to four times less prevalent than <a href="/articles/anomalous-left-coronary-artery-from-the-pulmonary-artery" title="Anomalous left coronary artery from the pulmonary artery">anomalous left coronary artery from the pulmonary artery (ALCAPA)</a>. There is a slight male predominance.</p><h5><strong>Associations</strong></h5><p>ARCAPA may be associated with a range of other cardiac abnormalities <sup>1</sup>, most commonly an <a href="/articles/aortopulmonary-septal-defect-1" title="Aortopulmonary septal defect">aortopulmonary septal defect</a> (also known surgically as aortopulmonary window) which is seen in 10 % of cases.</p><p>Other associations include (in decreasing order of frequency) <sup>1</sup>:</p><ul>
- +<li><p><a href="/articles/ventricular-septal-defect-1">ventricular septal defect (VSD)</a></p></li>
- +<li><p><a href="/articles/atrial-septal-defect-2">atrial septal defect (ASD)</a></p></li>
- +<li><p><a href="/articles/tetralogy-of-fallot">tetralogy of Fallot (TOF)</a></p></li>
- +<li><p><a href="/articles/patent-ductus-arteriosus">patent ductus arteriosus (PDA)</a></p></li>
- +<li><p><a href="/articles/bicuspid-aortic-valve" title="Bicuspid aortic valve (BAV)">bicuspid aortic valve (BAV)</a></p></li>
- +</ul><h4><strong>Clinical presentation</strong></h4><p>Patients may range from being completely asymptomatic with or without a murmur to presenting with sudden cardiac death. Patients are more likely to present later in life compared with those with ALCAPA. In a review of 223 patients in 193 papers <sup>1</sup>, 38% were asymptomatic at the time of diagnosis and the median age at diagnosis was 14 years with a bimodal age distribution at < 1 year and 40 to 60 years. Almost 50% of patients had a murmur at the time of diagnosis.</p><h4><strong>Pathology</strong></h4><p>ALCAPA refers to a cardiovascular anomaly where the <a href="/articles/right-main-coronary-artery" title="right main coronary artery">right main coronary artery</a> arises from the <a href="/articles/pulmonary-trunk">pulmonary trunk</a> instead of the left coronary sinus of the <a href="/articles/ascending-aorta">ascending aorta</a>. The aetiology is not well understood. The pathophysiology is similar to that seen in <a href="/articles/anomalous-left-coronary-artery-from-the-pulmonary-artery" title="ALCAPA">ALCAPA</a>.</p><h4><strong>Radiographic features</strong></h4><h5><strong>Cardiac CT</strong></h5><p>ECG-gated cardiac CT allows direct visualisation of anomalous right main coronary arterial origin from the posterior aspect of the pulmonary artery. The <a href="/articles/left-main-coronary-artery-1" title="Left coronary artery (LCA)">left coronary artery</a> may be unusually dilated and tortuous with evidence of collateral formation. Intercoronary collateral arteries along the external surface of the heart or within the interventricular septum may also be seen.</p><h4><strong>Treatment and prognosis</strong></h4><p>Surgical treatment aims to prevent coronary steal and restore the normal anatomic origin of the RCA <sup>1</sup>. The RCA origin can either be re-implanted onto the aorta or ligated then bypassed with an arterial or venous graft. The surgery is often performed with cardiopulmonary bypass.</p><h4><strong>See also</strong></h4><ul>