The use of whole thoracic ECG-gated MDCT for the de novo diagnosis of isolated patent ductus arteriosus in middle aged or older subjects

320 cardiac MDCT angiography in preoperative assessment of TOF and its variants: Does it worth it?

Background

Tetralogy of Fallot is the most common cyanotic congenital heart disease encountering a large spectrum of anatomical presentations with differing surgical approaches, and long-term outcomes ranging from ventricular septal defect with limited aortic overriding and mild pulmonary obstruction to a critical form of VSD and pulmonary atresia. TOF variants include PA/VSD, TOF/CAVC, TOF/DORV and TOF with absent pulmonary valve. Also, it may be accompanied with many associated intracardiac and extracardiac anomalies that may be of value when imaging and planning the surgical procedure.

Results

Our study included 22 cases of classic TOF, 18 with PA/VSD (12 were of type A, 5 were of type B and 1 was of type C), 3 with TOF/CAVC and 7 TOF/DORV. Sub-valvular RVOTO was detected in 94% of patients. A statistically significant difference was depicted between Echocardiography and MDCT in detecting supravalvular RVOTO, however no statistically significant difference was found in sub-valvular and valvular RVOTO detection. MDCT could efficiently characterize pulmonary arterial tree with statistically significant difference between both Echocardiography and MDCT in assessment of main, right and left pulmonary arteries with P value = 0.036,0.014 and 0.023 respectively. With calculation of Mc-Goon ratio in all patients, it was favorable (> 1.2) in 33 patients (66%). MDCT entailed 19 patients with PDA versus 15 depicted by Echocardiography and 25 MAPCAs per 11patients compared 8 MAPCAs per 7 patients detected by Echocardiography. Right sided aortic arch was found in 10 patients and 24 patients showed abnormal branching pattern. Coronary artery abnormalities were identified in eight patients. MDCT showed 100% sensitivity and 100% specificity in depicting aortic, coronary and other associated extracardiac vascular anomalies.

Conclusion

MDCT offers comprehensive anatomical assessment of TOF, and its variants providing superiority over echocardiography and comparable results to cardiac catherization with 100% sensitivity and specificity in evaluation of associated extracardiac vascular anomalies as well as pulmonary arteries characterization. It is worth using MDCT routinely in combination with echocardiography for the preoperative assessment of TOF and its variants representing a less invasive option than conventional catherization with lower radiation exposure.

Three steps approach for preoperative evaluation of tetralogy of Fallot patients: role of 128 MDCT

Background

Tetralogy of Fallot is the most common congenital cyanotic heart disease. Advances in surgical repair recently facilitate survival of the affected patients into adulthood with good quality of life. Despite imaging plays crucial role in diagnosis of TOF patients, no single diagnostic modality suffices for complete evaluation of TOF. Thus, different diagnostic tools should be used alone or in combination according to patient’s clinical question. This study aims to find out the agreement between the echocardiography and MDCT in evaluation of TOF patients prior to surgical repair.

Results

Three-step approach used in scanning TOF patients. Firstly, classic TOF findings, MDCT was comparable to echocardiography in overriding aorta (k = 0.6), VSD (k = 0.8), RVH (k = 0.4), and sub valvular pulmonary stenosis (k = 0.6). Echocardiography is superior to MDCT in evaluation of valvular stenosis (k = 0.4). MDCT was superior to echocardiography in supravalvular pulmonary stenosis. Secondary, surgical relevant findings, McGoon ratio calculated in 94.2%, small and major APCs in 45.5% and 28.5% respectively, PDA in 35% and anomalous coronary artery in 5.1%. Thirdly, other TOF-associated anomalies, common: ASD (34.3%) and RAA (28.3%), and persistent LSVC (10.3%). Uncommon: situs ambiguous (2.5 %), PAPVR (1.2%), and IVC anomalies (3.8%). MDCT was superior to echocardiography in surgical relevant findings and other TOF-associated anomalies.

Conclusion

MDCT is a crucial imaging tool for extra cardiac evaluation of TOF patients prior to surgical repair.