A Combination of Two Rare Coronary Anomalies Makes It Even Rarer: Right Sided Single Coronary Artery with Dual Left Anterior Descending Artery

Type II single coronary artery from right aortic sinus, retro-aortic left coronary artery and dual LAD: a rare association of coronary arterial variations

PURPOSE

The coronary arterial tree has a wide range of possible benign anatomical variations. It is important to differentiate them from coronary arterial anomalies, which can remain asymptomatic or in some cases lead to sudden death if undiagnosed.

METHODS

A 42-year-old female patient with a transient ST depression in right precordial leads performed an ECG-gated computed tomography angiography with dual layer spectral CT (IQon Elite Spectral CT, Philips, Amsterdam, The Netherlands) at Circolo Hospital of Varese.

RESULTS

A rare variant was observed and studied: a single common trunk arising from the right sinus of Valsalva which branches into a right coronary artery, a left anterior descending artery with malignant course and a left main with a retroaortic course; the left main gives origin to a dual anterior interventricular artery ("Dual LAD") and a left circumflex artery.

CONCLUSIONS

This type of variation was never described in the English literature. Identifying this variant is crucial for potential ischemic complications during sports activities or with the onset of atherosclerotic disease.

[Prevalence of coronary anomalies detected by computed tomography at the Instituto Nacional Cardiovascular- INCOR]

Objective

: To determine the prevalence of coronary anomalies (CA) in patients evaluated by 64-detector computed tomography (CT) at the Instituto Nacional Cardiovascular in Peru between 2016 and 2020.

Materials and methods

Retrospective observational study, coronary artery CT scans of 1486 patients were performed on a 64-detector row CT scanner and reviewed in search for coronary anomalies.

Results

The prevalence of CA detected by CT was 4.71% (70 cases) of which 64.3% were male. Abnormalities of origin were the most frequent, of which the origin of a coronary artery from the opposite coronary sinus was the most common (48.6%), with the right coronary being the main anomalous artery (31%), and the main path was interarterial (31%). Anomalous origin of the left main coronary from the pulmonary artery was found in 5 patients. Among the anomalies of the intrinsic coronary arterial anatomy the most frequent was the double left anterior descending artery (10%). Coronary fistulas accounted for 11.4% of cases.

Conclusions

The prevalence of CA detected by 64-detector CT in a Peruvian institute was 4.71%. The most frequent coronary anomaly was the origin of the right coronary artery from the left coronary sinus with interarterial trajectory.

Dual left anterior descending artery: diagnostic criteria and novel classification

Duplication of the left anterior descending artery is an uncommon coronary anomaly. Since no proper classification has been established after the initial description and numerical classification by Spindola-Franco et al., many newer numbers have evolved with many overlapping and unclassified variants described in the literature. Identification and reasonable management strategies for dual left anterior descending artery (LAD) are crucial in preventing the long-term disastrous consequences of inadequate revascularization. Clinicians and diagnosticians should be aware of this specific angiographic-based congenital coronary abnormality of the LAD. We, therefore, sought a new, reasonable classification of the dual LAD system, which would clarify this ambiguity, which also has therapeutic implications.

Supreme dominance of right coronary artery in a patient with typical angina

A 50-year-old woman presented to our hospital with Canadian Cardiovascular Society grade III angina of 4 months duration. Coronary angiography of the patient showed the absence of left main coronary artery from the left coronary sinus. There was a single right coronary artery (RCA) with a super dominant course from right coronary sinus. It also showed a left main coronary and left anterior descending artery arising separately from proximal RCA, with retroaortic and prepulmonic course, respectively. There was another independently arising small septal branch from the proximal RCA that supplied the proximal interventricular septum. The patient was managed with optimal medical therapy and had symptomatic relief.