Variations of pulmonary arteries and other associated defects in Tetralogy of Fallot

Holography-guided procedural planning for modifying Venus P-valve implantation technique in patients with left pulmonary artery stents: a case-series

Background

Venus P-valve™ (Venus Medtech, Hangzhou, China) is a self-expandable bioprosthetic valve that can be transcatheter-implanted in native right ventricular outflow tract (RVOT) patients. Valve implantation is technically challenging. Due to the implantation technique, left pulmonary artery (LPA) stents represent a relative contraindication to Venus P-valve. In this case series, we describe our experience in implanting Venus P-valve in patients with previous LPA stents and the use of holographic models to facilitate procedural planning.

Methods and results

From January to October 2023, 17 patients were scheduled for Venus P-Valve implantation. 16/17 (94%) patients were successfully implanted. 3/16 (18.7%) patients underwent Venus P-valve implantation with LPA stents. All patients underwent pre-operative CT scan. CT data set were employed to create three-dimensional (3D) holographic models (Artiness, Milan, Italy) of the entire heart, which were useful to plan valve implantation with a modified technique. Procedural success rate was 100%. No procedural complications occurred. All three patients presented good haemodynamic and angiographic results at discharge and follow-up visits.

Conclusion

This case-series underscores the feasibility of Venus P-valve implantation in patients with previous LPA stents. The use of holographic models facilitated procedural planning in these challenging anatomical scenarios.

Role of Cardiac CTA to Evaluate Branch Pulmonary Artery Stenosis and Ductal Insertion Pattern in Right-Sided Congenital Heart Defects

There is limited experience in evaluating abnormal ductus arteriosus (DA) insertion pattern by contrast-enhanced cardiac computed tomography (cardiac CT) in patients with right-sided obstructive cardiac defects. Retrospective review of 38 infants with right-sided obstructive cardiac defects who underwent a preoperative cardiac CT between 2016 and 2021. We reviewed the types of cardiac lesions, patterns of ductal insertion, frequency of pulmonary artery (PA) stenosis requiring intervention, total dose length product (DLP), and effective radiation dose. Of 38 infants, 45% were female, the median gestational age and weight were 37 (range 34-40) weeks and 2.95 (range 2-4) kg. The most common pathologies were pulmonary atresia with ventricular septal defect (24%) and tetralogy of Fallot (24%). The abnormal ductal insertion patterns were DA inserting into the left PA in 39%, DA bifurcating into branch PA in 32%, and DA inserting into the right PA in 13%. Of the 38 infants, 76% developed branch PA stenosis requiring intervention. Among patients with abnormal DA insertion, 44% required branch PA arterioplasty during their index surgery compared to 17% without abnormal DA insertion. Regardless of the type of abnormal DA insertion, 67% developed bilateral branch PA stenosis over time. The mean DLP was 8 mGy-cm and the mean calculated effective radiation dose was 0.312 mSv. The utilization of contrast-enhanced cardiac CT in infants with right-sided obstructive heart defects can offer crucial insights into abnormal ductus arteriosus insertion patterns. This information is valuable for effective procedure planning and for monitoring the development of branch pulmonary artery stenosis.

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.

Hidden pulmonary arteries in tetralogy of Fallot and pulmonary artery pressure in patients operated with a pulmonary artery

Introduction

The absence of a pulmonary artery is a rare congenital anomaly that occurs isolated or with other congenital cardiac disorders, particularly tetralogy of Fallot (TOF); meanwhile, a hidden pulmonary artery might exist and originate from a closed ductus arteriosus (DA), which can be stented to reach the artery.

Material and methods

This prospective study describes cardiac catheterization of nine TOF patients diagnosed with the absence of the left pulmonary artery before the operation. The patients were stratified into three groups: group one, whose closed DA was found and connected to the hidden pulmonary artery with a stent; group two, whose hidden pulmonary arteries were found via the pulmonary vein angiography; and group three, for whom we could not find the remnant of the DA, or our attempt to stent the DA to the hidden pulmonary artery was not successful. We also evaluated outcomes of six other surgically-corrected TOF patients who were operated with the absent left pulmonary artery.

Results

The first group included the patients aged 1, 24, and 30 months, whose CT angiography 6–9 months after stenting showed acceptable left pulmonary artery diameter for surgical correction, and the pulmonary vein angiography of the second group showed a hidden left pulmonary artery with a suitable diameter for surgical correction. However, we were unable to find or stent the DA of group three patients, aged 12, 38, 60, and 63 months. Earlier Angiography might have increased the chance of access to the hidden vessel. Apart from these three groups, follow-ups of six other patients previously corrected with only the right pulmonary artery revealed pulmonary artery hypertension in all patients.

Conclusion

The concealed pulmonary artery might be found, and stenting of the closed DA to it might be performed to improve the diameter of the diminutive pulmonary artery. This procedure may allow TOF total surgical correction with two pulmonary arteries. Besides, pulmonary vein angiography can reveal the hidden pulmonary artery.

Tetralogy of Fallot With Interatrial Communication of the Inferior Sinus Venosus Type: A Rare Association Causing Post-Operative Desaturation

This case report describes a rare association of tetralogy of Fallot with interatrial communication of the inferior sinus venosus type (inferior sinus venosus defect). The patient underwent intracardiac repair for tetralogy of Fallot at 8 months of age. His postoperative course was complicated by desaturation. On reexploration, interatrial communication of the inferior sinus venosus type was revealed which went unnoticed on transthoracic echocardiogram as well as on computerized tomogram.

Stenting and Reimplanting Disconnected Pulmonary Artery in Tetralogy of Fallot

Tetralogy of Fallot with absent pulmonary valve syndrome (TOF/APV) is a rare congenital malformation. Although pulmonary artery (PA) anomalies have been observed in TOF, its association with disconnected PA is extremely rare. We report successful stenting of the disconnected left PA in a 3-year-old boy with TOF/APV followed by surgical reimplantation. The significance of this transcatheter intervention for guidance during surgery and the importance of visualizing a ductal stump on angiography as an indicator of disconnected PA are discussed.