Echocardiographic and Surgical Correlation of Coronary Artery Patterns in Transposition of the Great Arteries

Value of preoperative echocardiography for the diagnosis of coronary artery patterns in neonates with transposition of the great arteries

BACKGROUND

Abnormal coronary pattern may complicate coronary transfer during arterial switch operation.

OBJECTIVE

To evaluate the accuracy of echocardiography in assessing the anatomy of coronary arteries in neonates with transposition of the great arteries, and determine impact on outcomes.

METHODS

We conducted a retrospective analysis of data in neonates with transposition of the great arteries. Preoperative echocardiographic coronary artery pattern and surgical intraoperative reports were compared. Mismatch between transthoracic echocardiography and surgical intraoperative reports and the impact on perioperative outcome were assessed. Coronary patterns were classified into four groups: type 1 (normal); type 2 (risk of coronary with intramural course); type 3 (coronary loop); and type 2+3.

RESULTS

Overall, 108 neonates who underwent an arterial switch operation were included: 68 were classified as type 1; seven as type 2; 32 as type 3; and one as type 2+3. Overall, 10 adverse events occurred. Five patients died, three from coronary causes. Survival was 96% at 1 month. Transthoracic echocardiography and surgical intraoperative reports differed in 17.6% of cases. Mortality was 15.8% in case of inappropriate diagnosis and 2.2% for appropriate diagnosis (P=0.01). Mortality in type 2 was 66.7% in case of discordance versus 0% when concordant. Multivariable analysis found that inappropriate preoperative transthoracic echocardiography diagnosis of coronary pattern was the only significant risk factor for mortality (P=0.04).

CONCLUSIONS

Echocardiography can assess coronary artery anatomy in neonates with transposition of the great arteries. Intramural coronary course is often misdiagnosed. Preoperative misdiagnosis of coronary artery anomaly may impact perioperative mortality. However, this assessment will have to be confirmed by further larger studies.

Commissural Malalignment as a predictor of coronary artery abnormalities in patients with transposition of great arteries

Background

In patients with transposition of the great arteries (TGA), commissural malalignment (CM) between semilunar valves may be associated with abnormal coronary (CA) pattern. We intend to assess the degree of CM with incidence of unusual CA anatomy.

Methods

We proposed a ratio to measure the distance of both ends of the anterior facing sinuses of the pulmonary valve from the facing commissure of the aortic valve. We labeled it as D1 and D2 distance. A ratio (C ratio) of the smaller distance (either D1 or D2 whichever is shorter) over the sum of both D1 and D2 was taken (D1 or D2 whichever is shorter / D1 + D2). We related this ratio with the incidence of the unusual CA anatomy in D-TGA patients.

Results

We had a total of 158 patients. We defined the point beyond which the C-Ratio becomes significantly associated with abnormal coronary artery pattern, this represents the median effective level (EL50). The EL50 of the C-Ratio was found to be equal to 31% (0.31). The prediction revealed that the CA pattern would most probably be usual when there is a minor commissural malalignment (C-Ratio less than the EL50) and most probably be unusual when there is a major malalignment (C-Ratio is greater than the EL50). The sensitivity was 71% and the specificity 88% (p-value < 0.0001).

Conclusions

The C-Ratio helps to categorize the degree of CM as minor (less than 0.31) or major (more than 0.31). A higher C-Ratio predicts a higher incidence of unusual CA pattern.