Dual left anterior descending coronary artery: CT findings. AJR Am J Roentgenol. 2008;191:1698-1701. [PMID: 19020238 DOI: 10.2214/ajr.08.1193]

Coronary Artery Anomalies: A Computed Tomography Angiography Pictorial Review

Coronary arteries have a wide range of anatomical variability, and their spectrum ranges from asymptomatic cases to those predisposed to hemodynamic compromise or even sudden cardiac death. This paper aims to review the classification of coronary artery anomalies (CAAs) and illustrate their imaging characteristics by highlighting the important role of CT coronary angiography. Some of the coronary anomalies usually met in current practice are the high origin coronary artery, multiple ostia, aberrant origin from the opposite/non-coronary Valsalva sinus, single coronary artery, ALCAPA syndrome, duplications of the left anterior descending artery, coronary fistulas, and extracardiac terminations. CT coronary angiography is a non-invasive diagnostic modality for CAAs. The complex anatomy of these anomalies can be accurately described by employing 3D reconstructions and post-processing techniques. Knowledge of the imaging characteristics and potential functional impact of these anomalies is essential for accurate diagnosis and therapeutic planning of patients.

Type 4 Dual Left Anterior Descending Artery: A Case Report of a Rare Congenital Coronary Anomaly

Dual left anterior descending artery (LAD) is a rare congenital coronary artery anomaly with a prevalence of approximately 1% in the general population. To date, 10 types of dual LAD artery anomalies have been reported. Among these, type 4 is one of the rarest. Knowledge and recognition of the dual LAD artery are important for correct diagnosis and planning of coronary bypass surgery and percutaneous coronary intervention. We report a case of a 59-year-old male with type 4 dual LAD artery who presented with dyspepsia and sweating for several months and had approximately 50%-70% stenosis in a major diagonal branch off the short LAD artery.

Distinguishing 'dual' from 'duplicated' right coronary artery: Revisiting the nomenclature

We report a case of a 53-year-old man with a "short RCA" seen coursing within the proximal part of the right atrioventricular (AV) groove and terminating in the mid-portion of the right AV groove and a "long RCA" seen to have a proximal course outside the right AV groove, over the free wall of the right ventricle, where it gave rise to the right ventricular and acute marginal branches before returning to the right AV groove in its distal course. The discussion highlights the need for revisiting the nomenclature of "dual RCA and drawing a distinction between "dual" and "duplicated" RCA.

The Role of Coronary CT Angiography in the Evaluation of Dual Left Anterior Descending Artery Prevalence and Subtypes: A Retrospective Multicenter Study

BACKGROUND

The aim of this multicenter study was to evaluate the prevalence and features of dual left anterior descending artery (LAD) subtypes using coronary CT angiography (CCTA).

METHODS

A retrospective multicenter analysis of 2083 CCTA from December 2020 to November 2022 was conducted to search for the presence and morphological features of dual LAD. The two classifications used were the updated classification of Spindola-Franco and the Jariwala classification. Statistical tests were conducted to evaluate the prevalence of dual LADs among sexes and its association with angina in patients without significant coronary stenoses and/or associated cardiac anomalies.

RESULTS

Dual LAD was observed in 124 (5.96%) patients analyzed. According to the Spindola-Franco revisited classification, type I dual LAD was the most common (71/124, 57.26%). According to the Jariwala classification, all cases were group I. In the general population, there was a higher prevalence of dual LAD among females (7.3% females vs. 5.1% males; p value: 0.04). No statistically significant difference was found in the prevalence of angina in the dual LAD population compared to the no dual LAD population (2.1% vs. 1.5%; p value: 0.10).

CONCLUSIONS

The acknowledgment and reporting of LAD duplication is helpful for an optimal management of coronary patients with this condition. Dual LAD was more frequent in the female population, mainly not related with angina. Myocardial bridge was more frequent in the dual LAD population than in the no dual LAD population.

Dual Left Anterior Descending Artery: Case series based on novel classification and its therapeutic implications

Angiographically, a “dual LAD” is described as two distinct arteries supplying the vascular territory of the LAD in parts, identified as the short LAD/LAD₁ and the long LAD/LAD₂. Using an easy-to-understand three-step approach, Jariwala et al unveiled a novel classification strategy for dual LAD systems in an attempt to decrease ambiguity in diagnosis and management of the anomaly. As part of our research, we looked at a wide range of published cases and case series in the literature, and also those reported from our hospital. In our novel classification system, we divide dual LADs into three main groups based on their origin and vascular territory, each of which is further divided into subgroups based on the course of LAD₁/LAD₂ and the variable feature that is a distinguishing attribute of the type of anomaly to be specified.

A review of 144 publications in the world literature revealed 340 patients eligible for the study. The median age was 58.8 years (SD - 11.42; range - 29–89) with male predominance (3.3:1). Cases in Group I comprised 60.6% of the total cases, followed by Group II (36.2%), and Group III (3.2%). Subgroup I-A was the most common in terms of dual LAD, followed by subgroup II-A. Acute coronary syndrome (45.5%) and chronic coronary syndrome (55.8%) were the most common clinical presentations in patients with significant coronary artery disease (30.8%).

Type X dual left anterior descending (LAD) artery masquerading as type 1 LAD — a case report

Background

Dual left anterior descending (LAD) coronary artery is a rare congenital anomaly. To date, eleven variants of dual LAD have been described with three published reports of type X dual LAD. Here, we describe a new variant of type X dual LAD with a short LAD artery masquerading as type 1 LAD.

Case presentation

A 42-year hypertensive female presented with recent onset angina with a treadmill test positive for inducible ischemia. Coronary angiography showed a normal right coronary artery (RCA). The left main coronary artery (LMCA) originated from the left sinus of Valsalva (SOV), giving rise to a LAD and the left circumflex artery (LCX). Appearing a normal angiogram with type 1 LAD based on its length, the presence of a large bare area in LAD territory (especially at the apex) and lack of septal branches prompted a search for an additional vessel. Right SOV injection showed a vessel originating separately from RCA, which was confirmed to be a long LAD on selective injection, with a pre-pulmonic course and giving rise to septal branches exclusively before wrapping around the apex. Computed tomography coronary angiography (CTCA) confirmed the pre-pulmonic course of long LAD, defined its entry to the distal interventricular septum to the right of short LAD, and ruled out other coronary artery anomalies. In the absence of a stenotic lesion in the epicardial coronaries, angina in our case was presumed to be due to microvascular dysfunction. She was discharged on beta-blocker therapy for co-existing hypertension and is asymptomatic on follow-up at one year.

Conclusions

A short LAD artery of type X Dual LAD could be potentially misdiagnosed as type 1 LAD based on its length. However, an active search for a long LAD could properly diagnose the case as a variant of type X dual LAD, which has important clinical implications. Its awareness is critical for cardiologists and cardiac surgeons to correctly interpret the coronary angiogram and plan proper management.

Cardiac-CT with the newest CT scanners: An incoming screening tool for competitive athletes?

Competitive athletes of all skill levels are at risk of sudden cardiac death (SCD) due to certain heart conditions. Prior to engagement in high-intensity athletics, it is necessary to screen for these conditions in order to prevent sudden cardiac death. Cardiac-CT angiography (CCTA) is a reliable tool to rule out the leading causes of SCD by providing an exceptional overview of vascular and cardiac morphology. This allows CCTA to be a powerful resource in identifying cardiac anomalies in selected patients (i.e. unclear symptoms or findings at ECG or echocardiography) as well as to exclude significant coronary artery disease (CAD). With the advancement of technology over the last few years, the latest generations of computed tomography (CT) scanners provide better image quality at lower radiation exposures. With the amount of radiation exposure per scan now reaching the sub-millisievert range, the number of CT examinations it is supposed to increase greatly, also in the athlete's population. It is thus necessary for radiologists to have a clear understanding of how to make and interpret a CCTA examination so that these studies may be performed in a responsible and radiation conscious manner especially when used in the younger populations. Our work aims to illustrate the main radiological findings of CCTAs and highlight their clinical impact with some case studies. We also briefly describe critical features of state-of-the-art CT scanners that optimize different acquisitions to obtain the best quality at the lowest possible dose.

Prevalence and morphologic features of dual left anterior descending artery subtypes in coronary CT angiography

OBJECTIVES

The purpose of this study was to identify the prevalence of dual left anterior descending artery and define the morphological features using coronary computed tomography angiography in order to raise awareness of dual left anterior descending artery among radiologists.

MATERIALS AND METHODS

The radiologic reports of 1912 patients who underwent coronary computed tomography angiography at our institution were searched retrospectively for the presence of dual left anterior descending artery. Computed tomography images of patients with dual left anterior descending artery were then reviewed, and the morphological features of dual left anterior descending artery were evaluated.

RESULTS

Dual left anterior descending artery was identified in 1.3% of the patients in this study population. Type 1 dual left anterior descending artery was the most common subtype (76%). Four additional cases that were not classified before were also detected.

CONCLUSION

Dual left anterior descending artery has a variety of subtypes reported mostly as odd cases, and gaining diagnostic awareness of dual left anterior descending artery is more critical, rather than listing and counting the subtypes. With the widespread use of coronary computed tomography angiography, it has become essential for radiologists to have knowledge about dual left anterior descending artery, as it is vital, especially for surgical planning.

Dual-source computed tomography coronary artery imaging in children

Computed tomography (CT) has a well-established diagnostic role in the assessment of coronary arteries in adults. However, its application in a pediatric setting is still limited and often impaired by several technical issues, such as high heart rates, poor patient cooperation, and radiation dose exposure. Nonetheless, CT is becoming crucial in the noninvasive approach of children affected by coronary abnormalities and congenital heart disease. In some circumstances, CT might be preferred to other noninvasive techniques such as echocardiography and MRI for its lack of acoustic window influence, shorter acquisition time, and high spatial resolution. The introduction of dual-source CT has expanded the role of CT in the evaluation of pediatric cardiovascular anatomy and pathology. Furthermore, technical advances in the optimization of low-dose protocols represent an attractive innovation. Dual-source CT can play a key role in several clinical settings in children, namely in the evaluation of children with suspected congenital coronary artery anomalies, both isolated and in association with congenital heart disease. Moreover, it can be used to assess acquired coronary artery abnormalities, as in children with Kawasaki disease and after surgical manipulation, especially in case of transposition of the great arteries treated with arterial switch operation and in case of coronary re-implantation.

A rare case of type X dual left anterior descending coronary artery

A dual left anterior descending (LAD) coronary artery is a rare, and benign congenital anomaly. In this anomaly, there is the presence of two LADs in the anterior inter ventricular sulcus (AIVS). One of the LADs is a short one that ends high in the AIVS. The other longer one enters the distal AIVS and feeds the apex. To date, 9 types of dual LAD variants, and one novel type X has been reported. Herein, we report a case of type X dual LAD with a literature review. <Learning objective: Dual left anterior descending coronary artery (LAD) is an important coronary anomaly to be aware of by interventional cardiologists to avoid misinterpretation of coronary angiography and surgical complications related to coronary interventions. We report a new variation of type X dual LAD with a literature review.>.

Prevalence and characteristics of dual left anterior descending artery in adult patients undergoing coronary angiography

Aim: To determine the prevalence and characteristics of dual left anterior descending artery (LAD) in adults undergoing catheter coronary angiography. Materials & methods: We identified cases with dual LAD by retrospectively analyzing 3233 angiograms done from January 2017 to June 2019. Results: Dual LAD was seen in 22 patients (0.68%). We identified type I dual LAD in 14 cases, type II in 7 cases and type III in 1 case. Significant stenosis was seen in proximal part of long LAD in 12 cases, in LAD proper in 7 cases and in proximal part of short LAD in 4 cases. Conclusion: Dual LAD is a rare anomaly. Its sound knowledge is essential for proper management of patients with coronary artery disease.

A New Variant of Dual Left Anterior Descending Artery Anomaly: Type XI

A dual left anterior descending (LAD) artery is a rare congenital anomaly which is classified into different types based on the origin, course and termination of the short and long LAD arteries. To date, 10 variants of dual LAD artery anomalies have been described. We report a 44-year-old woman who was referred to the Department of Radiology, Royal Hospital, Muscat, Oman, in 2017. Coronary computed tomography angiography revealed a dual LAD artery anomaly in which the short and long LAD arteries shared a common ostium with the right coronary artery from the right coronary sinus. To the best of the authors' knowledge, this type of variant has not been previously reported in the literature.

Overview of coronary artery variants, aberrations and anomalies

Coronary artery anomalies and variants are relatively uncommon congenital disorders of the coronary artery anatomy and constitute the second most common cause of sudden cardiac death in young competitive athletes. The rapid advancement of imaging techniques, including computed tomography, magnetic resonance imaging, intravascular ultrasound and optical coherence tomography, have provided us with a wealth of new information on the subject. Anomalous origin of a coronary artery from the contralateral sinus is the anomaly most frequently associated with sudden cardiac death, in particular if the anomalous coronary artery has a course between the aorta and the pulmonary artery. However, other coronary anomalies, like anomalous origin of the left coronary artery from the pulmonary artery, atresia of the left main stem and coronary fistulae, have also been implicated in cases of sudden cardiac death. Patients are usually asymptomatic, and in most of the cases, coronary anomalies are discovered incidentally during coronary angiography or on autopsy following sudden cardiac death. However, in some cases, symptoms like angina, syncope, heart failure and myocardial infarction may occur. The aims of this article are to present a brief overview of the diverse coronary variants and anomalies, focusing especially on anatomical features, clinical manifestations, risk of sudden cardiac death and pathophysiologic mechanism of symptoms, as well as to provide valuable information regarding diagnostic workup, follow-up, therapeutic choices and timing of surgical treatment.

Abnormalities of the Coronary Arteries in Children: Looking beyond the Origins

Coronary arterial abnormalities are uncommon findings in children that have profound clinical implications. Although anomalies of the coronary origins are well described, there are many other disease processes that affect the coronary arteries. Immune system-mediated diseases (eg, Kawasaki disease, polyarteritis nodosa, and other vasculiditides) can result in coronary arterial aneurysms, strictures, and abnormal tapering of the vessels. Because findings at imaging are an important component of diagnosis in these diseases, the radiologist's understanding of them is essential. Congenital anomalies may present at varying ages, and findings in hemodynamically significant anomalies, such as fistulas, are key for both diagnosis and preoperative planning. Pediatric heart surgery can result in wide-ranging postoperative imaging appearances of the coronary arteries and also predisposes patients to a multitude of complications affecting the heart and coronary arteries. In addition, although rare, accidental trauma can lead to injury of the coronary arteries, and awareness and detection of these conditions are important for diagnosis in the acute setting. Patients with coronary arterial conditions at presentation may range from being asymptomatic to having findings of myocardial infarction. Recognition of the imaging findings is essential to direct appropriate treatment. ^©RSNA, 2017.

Successful Restoration of Complete Heart Block to Normal Sinus Rhythm by Primary Angioplasty of Dual Left Anterior Descending Artery

Dual left anterior descending (LAD) artery is a rare coronary anomaly. We present a patient with a rare case of dual LAD, smaller one arising from the left main coronary stem and larger one from right coronary artery who presented with acute anterior wall myocardial infarction with complete heart block (CHB). Temporary pacemaker was implanted and coronary angiogram revealed critical occlusion of proximal LAD which was subsequently revascularized by primary angioplasty using drug-eluting stent (Xience prime, 2.75 × 23 mm) leading to recovery of CHB and restoration to normal rhythm. To the best of our knowledge, this is the first reported case of dual LAD presenting with CHB treated by primary angioplasty reported in the literature.

Prevalence of dual left anterior descending artery variations in CT angiography

PURPOSE

We aimed to evaluate the frequency and features of dual left anterior descending artery (LAD) variants using computed tomography (CT) angiography.

METHODS

A total of 1337 consecutive coronary CT angiography examinations performed between April 2010 and December 2013 were retrospectively evaluated for the presence of dual LAD. CT examinations were performed with either 64- or 320-row multidetector CT scanners. All CT angiography images were evaluated for the presence and morphologic features of dual LAD subtypes.

RESULTS

Fifty-six dual LAD variations (4%) were identified in this study population. Type 1 was the most common type of dual LAD (n=48), while Type 3 (n=3) and Type 4 (n=2) were infrequent and Type 2 was not detected. Additionally, we detected previously unclassified dual LAD variations in three cases.

CONCLUSION

Dual LAD may be a relatively more common variant than described in the medical literature, which is mostly based on catheter angiography studies. Coronary CT angiography seems markedly efficacious for detecting and documenting the anatomical details of dual LAD subtypes, as well as showing other associated cardiocoronary anomalies.

Single coronary artery with a pre-pulmonic dual left anterior descending artery and a retro-aortic left circumflex artery

We present two cases of an unusual coronary artery anomaly, namely, a single coronary artery with retro-aortic course of the left circumflex artery and pre-pulmonic course of the left anterior descending artery, and one of which showed a dual left anterior descending artery as well - a combination that has not yet been reported in the literature.

A new anomaly of the left anterior descending artery: Type X dual LAD

Dual left anterior descending (LAD) coronary artery anomaly is traditionally classified as four types anomaly by classical coronary angiogram. Nowadays, coronary computed tomographic angiography (CCTA) allows clinicians to understand other variants of dual LAD anomaly. Up to date, 9 types of dual LAD variants detected from not only classical coronary angiogram but also CCTA imaging have been reported.

In the present case, we aimed to show a novel dual LAD anomaly, which is demonstrated by CCTA during preoperative evaluation and it has not been previously reported.

Multidetector CT angiography characterisation of Type 4 dual left anterior descending coronary artery

Duplication of the left anterior descending (LAD) coronary artery is a rare anomaly (incidence 1%) characterized by a short LAD that terminates high in the anterior interventricular groove and a long LAD that has a proximal course outside the anterior interventricular groove and returns to the groove in its distal course. The Type 4 variant of this anomaly is extremely rare whereby a long LAD arises from the right coronary sinus with a short LAD arising from the left mainstem. We present a case of Type 4 dual LAD which was characterised with multi-detector computed tomography (CT).

A rare anomaly of LAD mimicking CTO

A 65-year-old man was admitted into our hospital because of the detailed examination for abnormal Q waves in inferior leads on an electrocardiogram. Coronary angiography and 320-row area detector computed tomography (ADCT) revealed "dual left anterior descending artery (LAD)", which was a rare anomaly of the LAD and chronic total occlusion (CTO) at segment 2 of the right coronary artery (RCA). The course of the anomalous LAD arising from the proximal portion of the RCA was specifically identified between aortic root and right ventricular outflow tract (RVOT) by 320-row ADCT. The anomalous LAD had potential risk of myocardial ischemia because of the compression from aortic root and RVOT during exercise. We performed technetium myocardial perfusion scintigram to evaluate exercise-induced ischemia in the territory of the anomalous LAD and to decide therapeutic strategies including coronary artery bypass grafting surgery to the vessel. The scintigram revealed no exercise-induced ischemia in anteroseptal wall and a constant perfusion defect in posteroinferior wall of the left ventricle. Thus, we decided to treat the patient with pharmacological treatment in the outpatient setting. This report suggests that it is important to recognize the variants of coronary arteries for optimal treatment. <Learning objective: Coronary artery anomalies such as "dual left anterior descending artery" are particularly rare. Anomalous coronary artery may contribute to exercise-induced myocardial ischemia and sudden cardiac death by the compression of the great arteries even when coronary angiography revealed no fixed stenosis in the artery. We have to recognize the types, clinical features and functional properties of the coronary artery anomalies for preventing misdiagnosis of coronary angiogram and deciding the best treatment for patients.>.

An unusual case of dual left anterior descending artery with coronary computed tomographic angiographic correlation

Dual left anterior descending artery (LAD) is a rare coronary anomaly that is important to recognize at coronary imaging as it may influence reperfusion strategies. Four types of dual LAD are described by the traditional literature. We present a novel case of dual LAD with coronary computed tomographic angiographic correlation that does not fit into this classification system. Rather, our case supports the recently proposed notion of adding a fifth variant to the traditional dual LAD classification system.

Multidetector computed tomography imaging of coronary artery anomalies

PURPOSE

The purpose of the study was to determine the prevalence of coronary artery anomalies and to demonstrate in which cases multidetector computed tomography has an additional clinical value compared with the conventional angiography.

MATERIAL AND METHODS

A total of 2375 multidetector computed tomography studies were retrospectively reviewed to determine the dominance of the coronary artery anomalies. The classification of coronary artery anomalies was made according to anatomical criteria--origin, course, intrinsic anatomy, and termination--and clinical relevance--benign versus malignant.

RESULTS

The coronary artery system was right dominant in 83.99%, left dominant in 8.0%, and co-dominant in 9.01% of the cases. The incidence of the origin and/or course anomalies was 1.76%, that of fistulas was 0.42%, and that of myocardial bridges was 10.82%. Multidetector computed tomography was performed after conventional angiography in 23 cases and it provided additional information regarding its origin and proximal course, as well as its relationship with the aortic root and main pulmonary trunk in 100% of the cases; eight malignant cases were found. In addition, in all of (100%) the six cases with coronary artery fistulas, conventional angiography failed to detect their terminations, which were clearly depicted by multidetector computed tomography.

CONCLUSION

Multidetector computed tomographic angiography is superior to conventional angiography in delineating the ostial origin and proximal course of anomalous coronary arteries. Furthermore, it reveals the exact relationship of anomalous coronary arteries with the aorta and the pulmonary artery. Anomalies of the intrinsic anatomy and the termination of coronary arteries are also better visualised with multidetector computed tomography.

[Circumflex angioplasty in a patient with type IV dual left anterior descending coronary artery. Proposal for updating the classification of Spindola-Franco]

The normal anatomy of coronary arteries includes a kind of variants with regard to its origin, distribution and route, which makes that 2 patients do not have coronary arteries exactly alike. Left anterior descending artery could have anatomical variations that do not affect the normal supply of blood to the corresponding myocardial territory. In our 25 years of experience, and more than 11,000 coronary angiographies, we have found only one patient with a type IV dual left anterior descending coronary artery. In this article we show the case of a patient with the described coronary anomaly, presenting a severe stenosis of the circumflex artery which was successfully treated percutaneously. Besides, a proposal for updating the classification of Spindola-Franco is made, where the 4 types previously described were kept invariable, and 7 anatomical variants or subtypes were added.

Identifying, characterizing, and classifying congenital anomalies of the coronary arteries

The clinical manifestations of coronary artery anomalies vary in severity, with some anomalies causing severe symptoms and cardiovascular sequelae and others being benign. Cardiovascular computed tomography (CT) has emerged as the standard of reference for identification and characterization of coronary artery anomalies. Therefore, it is important for the reader of cardiovascular CT images to be thoroughly familiar with the spectrum of coronary artery anomalies. Hemodynamically significant anomalies include atresia, origin from the pulmonary artery, interarterial course, and congenital fistula. Non-hemodynamically significant anomalies include duplication; high origin; a prepulmonic, transseptal, or retroaortic course; shepherd's crook right coronary artery; and systemic termination. In general, coronary arteries with an interarterial course are associated with an increased risk of sudden cardiac death. Coronary artery anomalies that result in shunting, including congenital fistula and origin from the pulmonary artery, are also commonly symptomatic and may cause steal of blood from the myocardium. Radiologists should be familiar with each specific variant and its specific constellation of potential implications.

Importance of multi-detector computed tomography for percutaneous coronary intervention in a patient with type V dual left anterior descending artery

A 58-year-old woman came to our hospital because of chest pain. Multi-detector computed tomography (MDCT) showed type V dual left anterior descending artery (LAD) and a 90% stenosis in segment 1 of the right coronary artery. Two days after examination, she was admitted to our hospital because of recurrent chest pain. She was diagnosed with acute myocardial infarction. Coronary angiography showed a 99% stenosis in segment 1 and a dual LAD. She received successful percutaneous coronary intervention (PCI) to segment 1 with a bare metal stent. Type V dual LAD is a rare and complicated coronary anomaly with the short LAD originating from the left sinus of valsalva and the long LAD originating from the right sinus of valsalva. Identifying anatomy of the coronary artery is important when making a strategy for PCI. In types IV-VI dual LAD, the anatomic features can be misinterpreted at coronary angiography. MDCT was useful in understanding the anomaly of dual LAD and performing PCI in the present case.

Complex coronary artery anatomy in a patient with prolapsing left atrial myxoma

The case of an asymptomatic patient with prolapsing left atrial myxoma, in whom preoperative coronary angiography revealed a rare coronary artery anatomy in the absence of atherosclerotic obstructive disease, is presented. There was a type IV dual left anterior descending (LAD) artery with intraseptal course of the right aortic sinus-connected (long) LAD artery and an ectopic left circumflex artery originating from the right aortic sinus and having a retroaortic course. The patient underwent successful surgical excision of the mass which was confirmed by histology to be cardiac myxoma. This particular coronary artery anatomy has only been described once, and this is the first reported case of its combination with cardiac myxoma. This report highlights the importance of differentiating between the possible courses of such ectopic coronary arteries. The angiographic signs which enabled differentiation of the intraseptal course of the long LAD artery from the malignant interarterial course with which it is frequently confused are presented.

Dual anterior interventricular artery type IV: a rare anatomical variation

Type IV dual anterior interventricular artery (AIVA) is a rare variant that involves bilateral connection of this vessel to the left main coronary artery and right coronary artery or right aortic sinus. We present a case of such a variant where the ectopic branch traveled an intraseptal course, i.e., through the superior aspect of the crista supraventricularis in a subendocardial position and then intramyocardially inside the upper interventricular septum to reach the anterior interventricular sulcus and descend toward the apex. In a left anterior oblique view, this course lacked the typical caudal anterior loop but it was recognized by virtue of emergence of a septal branch as the first branch of the ectopic AIVA. Recognition of this variant and differentiation among the possible courses of the ectopic branch is important for patient management.