Coronary Artery Anomalies in Animals

Abstract

Coronary artery anomalies represent a disease spectrum from incidental to life-threatening. Anomalies of coronary artery origin and course are well-recognized in human medicine, but have received limited attention in veterinary medicine. Coronary artery anomalies are best described in the dog, hamster, and cow though reports also exist in the horse and pig. The most well-known anomaly in veterinary medicine is anomalous coronary artery origin with a prepulmonary course in dogs, which limits treatment of pulmonary valve stenosis. A categorization scheme for coronary artery anomalies in animals is suggested, dividing these anomalies into those of major or minor clinical significance. A review of coronary artery development, anatomy, and reported anomalies in domesticated species is provided and four novel canine examples of anomalous coronary artery origin are described: an English bulldog with single left coronary ostium and a retroaortic right coronary artery; an English bulldog with single right coronary ostium and transseptal left coronary artery; an English bulldog with single right coronary ostium and absent left coronary artery with a prepulmonary paraconal interventricular branch and an interarterial circumflex branch; and a mixed-breed dog with tetralogy of Fallot and anomalous origin of all coronary branches from the brachiocephalic trunk. Coronary arterial fistulae are also described including a coronary cameral fistula in a llama cria and an English bulldog with coronary artery aneurysm and anomalous shunting vessels from the right coronary artery to the pulmonary trunk. These examples are provided with the intent to raise awareness and improve understanding of such defects.

Non‐electrocardiographic‐gated computed tomographic angiography can be used to diagnose coronary artery anomalies in Bulldogs with pulmonary valve stenosis

“…18 A multiplane image is possible with angiography, however it often requires multiple contrast injections, specialized equipment, and cannot be performed simultaneously. 10 The calculated effective dose reported in this study is similar to those with retrospective electrocardiographic-gated CT coronary angiography in humans, which reports 20 ± 3 mSv. 20 While CT angiography does not ameliorate the radiation exposure to the dog relative to an angiogram, it does decrease the potential radiation dose for the operator (at the authors institution) as they are not present in the room for CT angiography, which is considered an additional advantage.…”

“…Second, CT angiography offers a simultaneous multiplane assessment and the ability to create maximum intensity projections, which may improve conspicuity of a coronary anomaly . A multiplane image is possible with angiography, however it often requires multiple contrast injections, specialized equipment, and cannot be performed simultaneously …”

“…The presence of a type R2A anomaly increases a dog's risk of sudden death during balloon valvuloplasty and is considered a contraindication for standard balloon valvuloplasty . Coronary anomalies with a single coronary ostium, other than the R2A type, have been also reported in Bulldogs, Boxer dogs, and other breeds . Aortic root angiography has been recommended prior to balloon valvuloplasty to identify coronary artery anatomy and assess for the presence of a coronary anomaly .…”

“…4,7 Coronary anomalies with a single coronary ostium, other than the R2A type, have been also reported in Bulldogs, Boxer dogs, and other breeds. [8][9][10] Aortic root angiography has been recommended prior to 38 c 2018 American College of Veterinary Radiology Vet Radiol Ultrasound. 2019;60:38-46. wileyonlinelibrary.com/journal/vru balloon valvuloplasty to identify coronary artery anatomy and assess for the presence of a coronary anomaly.…”

Vascular and Cardiac CT in Small Animals

“…ECG-gated cardiac CT is also useful in patients with congenital cardiac defects such as PDA, PS, or more complex congenital heart diseases. Moreover, it is helpful for planning surgical and interventional procedures [16,40] (Figures 15, 16). Vascular and Cardiac CT in Small Animals http://dx.doi.org/10.5772/intechopen.69848…”