Cardiovascular Revascularization Medicine xxx (2015) xxx–xxx

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Cardiovascular Revascularization Medicine

Anomalous right coronary artery: case series and review of literature☆ Prakash Suryanarayana a, Justin Z. Lee b,⁎, Aiden Abidov a, Kapildeo Lotun a a b

University of Arizona Department of Cardiovascular Diseases University of Arizona Department of Internal Medicine

a r t i c l e

i n f o

Article history: Received 22 December 2014 Received in revised form 14 March 2015 Accepted 26 March 2015 Available online xxxx Keywords: Anomalous coronary artery Percutaneous coronary intervention Radial access approach

a b s t r a c t Anomalous right coronary arteries (ARCA) are extremely rare in general population. Although mostly asymptomatic and recognized incidentally on cardiac catheterizations, they can be catastrophic and can cause sudden cardiac death. Sudden cardiac deaths are more common when the anomalous vessel runs an inter-arterial course between the aorta and the pulmonary artery. Asymptomatic patients with malignant course of anomalous coronaries can pose clinical dilemmas. Based on prior experience, management of asymptomatic ARCA with malignant course should be subjected to a risk–benefit analysis. This case series begins with a brief description of four separate cases of ARCA. They had their origin in the left coronary sinus or off left anterior descending artery (LAD). Three of them had anterior course between aorta and pulmonary trunk, confirmed by coronary CT angiography (CTA). Whereas two of our patients presented with chronic symptoms, two presented as acute cases with electrocardiographically proven STEMI. These cases were managed differently; by conservative, surgical or interventional approaches. All four cases had good final outcomes. This goes to show how different treatment options can be employed in management of complications associated with anomalous coronary arteries. It is also interesting to note that the radial access provides better guide support that is needed to tackle complex lesions. Many operators have been using radial approach for anomalous coronary interventions. We have successfully employed radial technique after failed trans-femoral attempts and also in STEMI situations. Based on our experience, right radial approach appears to be safer and quicker. © 2015 Elsevier Inc. All rights reserved.

1. Introduction Anomalous right coronary artery (ARCA) is an uncommon congenital anomaly with varied clinical outcomes. Many of the coronary anomalies are asymptomatic, but there is also an association with serious outcome such as sudden cardiac death. We present four cases of ARCA, as well as a brief review of the literature. 2. Case 1 A 55-year-old male presented with exertional chest pain of two years duration. Physical examination and lab studies were unremarkable. Coronary angiography documented the presence of moderate LV dysfunction with EF of around 30–35%. Coronary angiogram performed via femoral approach showed single coronary artery with ARCA originating from LAD and non-obstructive CAD. Since the anomalous artery was detected during left coronary injection using JL4 catheter, no further attempts were made to identify a separate right coronary artery ostium. A non-selective aortogram was performed to confirm these ☆ There are no conflicts of interest. ⁎ Corresponding author at: 1501 N. Campbell Avenue, RM 6336, Tucson, AZ 857245040. Tel.: +1 520 850 2692; fax: +1 520 626 6020. E-mail address: [email protected] (J.Z. Lee).

findings. Coronary CT angiogram (CTA) was suggestive of right dominant circulation and anomalous RCA arising from LAD, coursing between aorta and pulmonary artery (Fig. 1). The caliber of the vessel in this region appeared to be narrow with more normal caliber distally. He was managed conservatively with suggestion to stop alcohol consumption. Since there was no significant improvement in LV systolic function despite optimal therapy, ICD was implanted. He has been doing well after two years of follow up. 3. Case 2 A 47-year-old male with hypertension and dyslipidemia presented with sudden onset of chest pain. Initial EKG showed minimal STelevation in the inferior leads. The patient was taken emergently to the catheterization lab in view of ongoing chest pain, although only subtle ST elevation was noted on the EKG. Emergent cardiac catheterization from femoral approach revealed an ARCA arising from left coronary sinus. Despite multiple attempts with different catheters (JR4 initially, followed by AL1 and multi-purpose catheters), there was difficulty in engaging the RCA ostium, and hence no intervention could be performed). However, follow up troponin levels were only minimally elevated (maximum value of 0.15 ng/ml). Echocardiogram showed normal LV systolic function with LVEF of 60% and no regional wall motion abnormalities. Coronary CT-angiography was subsequently done

http://dx.doi.org/10.1016/j.carrev.2015.03.006 1553-8389/© 2015 Elsevier Inc. All rights reserved.

Please cite this article as: Suryanarayana P, et al, Anomalous right coronary artery: case series and review of literature, Cardiovasc Revasc Med (2015), http://dx.doi.org/10.1016/j.carrev.2015.03.006

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was engaged with AL1 guide catheter, it had to be changed out to a 6 F Barbeau guide catheter for better guide support during the intervention. During diagnostic angiogram, an ARCA with takeoff adjacent to the left coronary artery was noted with 99% stenosis in its mid-portion with thrombus (Fig. 3). Export catheter was used for thrombus aspiration. The stenotic segment of the ARCA was then stented. Echocardiogram performed on the following day demonstrated borderline LV systolic function with EF of 50–55%. No definite regional wall motion abnormalities were seen. Cardiac enzymes were within normal limits at admission (prior to the procedure) and increased to a maximum value of 4 ng/ml. Subsequent coronary CT-angiography revealed anomalous origin of the RCA from the left coronary sinus with an inter-arterial course (Fig. 4). The patient was well post-PCI with no in-hospital complications. 5. Case 4

Fig. 1. Cardiac CT-scan of case 1. This coronary CT with 3D reconstruction shows narrowed segment of anomalous RCA (arrow) at the site where it is coursing between the aorta and pulmonary artery.

which showed an ARCA with tortuous takeoff from the left coronary sinus that coursed between the aorta and pulmonary artery (Fig. 2). There was 75% narrowing of the proximal segment in reference to the mid-segment of the vessel, but no plaques or obstructive lesions were present. The patient underwent a mini-sternotomy, unroofing of ARCA and aortic valve commissural suspension (commissure between left and right cusps of the aortic valve). Post-operatively, the patient was well and was symptom free on discharge and subsequent follow-up.

A 66-year-old man presented with chest pain upon exertion. His past medical history was significant for stents in the LAD, left circumflex artery and RCA five years ago. During the previous cardiac catheterization six months earlier, femoral approach was employed. Although diagnostic images revealed anomalous origin of RCA from anterior aspect of the left coronary sinus, no intervention could be performed due to extreme technical difficulty secondary to inadequate guide support. When AL1 diagnostic catheter could not engage the anomalous vessel, attempts were made using various guide catheters such as JL4, JL 4.5, multi-purpose EBU 3.5 and AL3 guide catheters. Due to ongoing symptoms, the procedure was reattempted at a later date via right radial approach, and the focal lesions within the ARCA were stented easily (Fig. 5). A Tiger 4.5 catheter was used for diagnostic study, and 6 F Barbeau guide catheter was used for the intervention. There were no post-PCI complications, and he has been doing well on subsequent follow-up (Table 1). (See Fig. 6.) 6. Discussion

4. Case 3 6.1. Epidemiology A 73-year-old male presented with sudden development of chest pain while exercising. EKG showed ST-segment elevation in inferior leads, and the patient was taken directly for emergent cardiac catheterization. The procedure was performed using the radial access approach. Once the present anomalous right coronary artery was recognized during the initial injection of left coronary system using Tiger 4 guide catheter, we decided to switch out to AL1 guide catheter. Although ARCA

Anomalous coronary artery is a rare clinical entity with varied clinical outcomes, ranging from a totally asymptomatic course to sudden cardiac death. This has been a subject of an array of clinical as well as autopsy studies so far. Studies from across the globe show a relatively constant incidence of coronary anomalies at around 1–1.5% [1], with many studies documenting right coronary artery (RCA) as the commonest anomalous coronary artery [2–4]. The prevalence of ARCA, as determined from coronary angiography studies, ranges from 0.06% to 0.5 [3,5]. 6.2. Clinical presentations and pathophysiology

Fig. 2. Cardiac CT-scan of case 2. This cardiac CT image with 3D reconstruction demonstrates the interarterial course of anomalous RCA (arrow) between the root of pulmonary artery and aorta.

A variety of anomalous origins of RCA have been reported in literature, which include origin from descending thoracic aorta, left main coronary, left circumflex, above/from left sinus of Valsalva, the pulmonary arteries or even below the aortic valve [1,2,6–13]. After the anomalous take off, the artery may run anterior, posterior or in between the major vessels at the base of the heart, the last course constituting what is famously known as “malignant” type of anomaly due to risk of extrinsic compression and sudden death. Most ARCA are asymptomatic and are seen as incidental findings on coronary angiography. They may also be responsible for a whole host of clinical manifestations that include angina pectoris, myocardial infarction or even sudden cardiac death. ARCA originating from the contralateral aortic sinus that runs between pulmonary artery and aorta has received much attention because of its association with sudden death [14–16]. However, the exact pathophysiological basis for such association is unclear. The most common theory is the mechanical compression of the ARCA, especially during exercise [1,13,17]. Other proposed mechanisms include presence of valve like ridges, acute angulation of the

Please cite this article as: Suryanarayana P, et al, Anomalous right coronary artery: case series and review of literature, Cardiovasc Revasc Med (2015), http://dx.doi.org/10.1016/j.carrev.2015.03.006

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Fig. 3. Angiography of case 3. Angiogram showing significant stenosis in the mid-portion of the anomalous right coronary artery prior to intervention (left) and post-PCI (right).

artery as it traverses from left to right [18], slit like coronary orifice, acute angled take off, and presence and length of intramural segments of coronary vessel. Many such patients had been asymptomatic before the fatal event. Malignant inter-arterial course of ARCA was seen in the first three patients in our cases. First case demonstrates an additional unique feature. Here, the RCA originated from LAD in the absence of a normally situated right coronary ostium. This is considered a variant of single left coronary artery, and only ten such cases have been described in medical literature [19–25]. Except for the first two patients, ARCA was stenosed due to atherosclerotic coronary artery disease. Although ARCA has been hypothesized to predispose an early development of coronary artery disease because of underlying microinjury due its course, the issue may still be controversial [26].

6.3. Treatment and outcomes As most of the ARCA are incidentally detected, management of such cases may pose dilemma in the minds of treating physicians. Confusion arises when they are asymptomatic but have “malignant” course because decisions regarding the management of asymptomatic patients

Fig. 4. Cardiac CT-scan of case 3. This CT image shows anomalous RCA originating in left coronary sinus and then coursing anteriorly. This was noted to be interarterial. Also note the stent in anomalous RCA (arrow). LAD appears to be diffusely diseased.

with these coronary anomalies are less well defined. In an asymptomatic patient with ARCA, dilemma may arise while deciding an invasive (percutaneous or operative) management for a condition that is usually benign, but has a small risk of sudden death. There have been noticeable differences in presentation and clinical course among asymptomatic patients with ARCA and anomalous left coronary artery (ALCA). The vast majority of deaths have occurred in ALCA patients, whether previously diagnosed or not [27]. Based on this, surgical repair upon diagnosis is justified in all ALCA patients. The operative decisions regarding patients with ARCA who are asymptomatic must be evaluated based on risk–benefit analysis relating to the occurrences of sudden death and the number of asymptomatic patients who have the anomaly [28]. The operative risks related to ARCA surgery as well as surgical outcomes are important considerations in the process. Other factors that should be taken into account include the age of the patient, as there is a reduced risk of sudden death with age [14]. The clinical outcome of ARCA is most often benign. The incidence of sudden death in asymptomatic patients with ARCA is extremely low [15,29]. Over the course of past 25 years, clinical reports describe 10 patients who died suddenly with RCA arising from left coronary artery sinus. Brothers et al [30] have reported significant sub-clinical changes indicative of myocardial ischemia in post-operative patients after surgical unroofing procedures. Nine of the 24 patients met criteria for ischemia at an average of 15 months after surgical repair. These included 8 of 16 patients with ARCA and 1 of 10 with anomalous LCA. Thus, more conservative approach is probably ideal in an asymptomatic patient with ARCA, without inter-arterial course. Generally, either percutaneous coronary intervention (PCI) or surgery is considered when the patient is symptomatic or with evidence of ischemia or arrhythmia during exercise–stress test [28]. The surgical options for RCA anomalies include unroofing and reimplantation of the RCA, and CABG [31]. In our first patient, heart failure was thought to be secondary to chronic alcoholism, as narrowed segment of ARCA could not explain globally hypokinetic LV. Second patient had difficult anatomy, which was not amenable to interventional management. Surgery was eventually performed. Third and fourth cases demonstrate the feasibility of PCI that have been increasingly successful in managing lesions in ARCA, when attempted via right radial approach. Transfemoral procedures are technically challenging and require use of guide catheters that are designed for left coronary artery, which do not provide adequate back up. It is also difficult to maneuver the guide catheters in order to obtain engagement in a coaxial manner. The procedure can get complicated with use of multiple guide catheters, increased procedure time and need for excessive amounts of contrast injection. As might be expected, there have been multiple reports of poor guide support and procedural failures with attempted PCI of the ARCA lesions when performed by femoral approach, especially when deep

Please cite this article as: Suryanarayana P, et al, Anomalous right coronary artery: case series and review of literature, Cardiovasc Revasc Med (2015), http://dx.doi.org/10.1016/j.carrev.2015.03.006

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Fig. 5. Angiography of case 4. Angiogram showing the narrowed segment of ARCA prior to the intervention (left) and post-PCI (right).

intubation is needed to tackle the complex lesions [32]. There have been a few prior reports on tackling complicated ARCA lesions using interesting and novel techniques. Yumoto K et al [33] described an interesting approach using an inner catheter with “mother and child technique” under multislice CT guidance. When AL1 guide catheter did not provide adequate support during ARCA interventions, some operators have used balloon-anchoring techniques [34]. Sun et al [35] achieved success with 6 F left coronary bypass guide catheter. But, most of these techniques could be challenging as well as time consuming. Operators experienced in transradial procedures have recommended the right radial approach as an excellent alternative in patients with ARCA arising from the left sinus of Valsalva [36]. Shallow angle of the innominate artery as it arises from aorta makes it easier for selective cannulation of ARCA arising from contralateral sinus of Valsalva via right radial approach, and deep intubation appears to be easier by this route, according to a prior report [37].

6.4. Conclusions ARCA is usually benign but predisposes to a small risk of sudden cardiac death. Management of ARCA mainly depends the clinical presentation and requires careful risk–benefit analysis of treatment options. When interarterial course or obstructive lesions are detected, selective cannulation via right radial approach appears to be a promising management strategy, even in STEMI situations. In our institution, we successfully perform right radial-access based procedures on ARCA ?thyc=5?> cases. We use guide catheters such as MRESS (Medtronic Inc., Minneapolis, Minnesota) and Barbeau (Cordis, Miami, Florida) catheters with good procedural success. Based on overall

limited experience, this strategy appears to be safe and is associated with higher success rates, reduced procedure time and possibly, reduced contrast exposure.

Acknowledgements We thank Irbaz Bin Riaz, MD and Ismail Tabash, MD for their assistance with the manuscript.

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Table 1 Clinical characteristics, course of RCA and treatment. Patient

1

2

3

4

Age (years) Chief complaint Origin of RCA Course Presence of significant coronary artery disease Management

55 Chest pain for two years Left anterior descending artery Inter-arterial No, but narrowing noted along inter-arterial segment Conservative with ICD placement

47 Sudden onset chest pain Left coronary cusp Inter-arterial with tortuous acute takeoff Yes

73 Sudden onset chest pain Left coronary cusp Inter-arterial Yes

66 Chest pain on exertion Left coronary cusp Inter-arterial Yes

Surgical

Access site Catheter/Guide used

Femoral JL4 for the single coronary artery 80 cc 15 min

Femoral AL1, Multi-purpose, EBU 3.5 270 cc 18 min

Percutaneous coronary intervention via radial approach Radial Tiger 4 for left coronary AL1 followed by Barbeau 325 cc 40.8 min

Percutaneous coronary intervention via radial approach Radial Barbeau guide catheter

Amount of contrast used Fluoro time

299 cc 43.8 min

NB: CTA = CT angiography, RCA = right coronary artery, ICD = implantable cardioverter defibrillator.

Please cite this article as: Suryanarayana P, et al, Anomalous right coronary artery: case series and review of literature, Cardiovasc Revasc Med (2015), http://dx.doi.org/10.1016/j.carrev.2015.03.006

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Fig. 6. Intra-vascular ultrasound of case 4. IVUS showing the origin and course of RCA (arrow) between the aorta (solid arrow) and pulmonary artery (arrow head).

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Please cite this article as: Suryanarayana P, et al, Anomalous right coronary artery: case series and review of literature, Cardiovasc Revasc Med (2015), http://dx.doi.org/10.1016/j.carrev.2015.03.006

Anomalous right coronary artery: case series and review of literature.

Anomalous right coronary arteries (ARCA) are extremely rare in general population. Although mostly asymptomatic and recognized incidentally on cardiac...
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