Eilers LF, Britt JJ, Weigand J, Penny DJ, Gowda ST, Qureshi AM, Stapleton GE, Khan A, Webb MK, Bansal M.Pediatr Cardiol. 2023 May 21. doi: 10.1007/s00246-023-03178-x. Online ahead of print. PMID: 37210685
Take Home Points:
- Cardiac magnetic resonance imaging (CMR) allows for a comprehensive assessment of ventricular function, aortopulmonary collateral burden, and lymphatic abnormalities.
- Combined CMR and cardiac catheterization led to a decrease in catheterization duration, amount of contrast received, and fluoroscopy time.
- CMR performed prior to the catheterization allowed for more targeted aortopulmonary collateral occlusion without a change in short term post-operative outcomes.
Commentary from Dr. Ryan Romans (Kansas City, MO), section editor of Congenital Heart Disease Interventions Journal Watch:
Patients with single ventricle congenital heart disease undergo staged palliation to separate the systemic and pulmonary circulations. The final stage is an inferior cavopulmonary anastosis, or Fontan procedure. Survival through stage palliation has improved in the modern era, though there is still significant morbidity (including systemic ventricular dysfunction, protein losing enteropathy, plastic bronchitis, liver and kidney dysfunction, lymphatic dysfunction). This morbidity highlights the need to ensure appropriate patient selection for Fontan completion versus consideration for hear transplant evaluation. Typical evaluation prior to Fontan has included echocardiography and cardiac catheterization. However, cardiac magnetic resonance (CMR) offers the ability to define anatomy, provide a more thorough assessment of ventricular function, better quantify AV valve regurgitation, quantitatively assess aortopulmonary (AP) collateral burden, and define lymphatic abnormalities prior to Fontan. The authors hypothesized that combined CMR and cardiac catheterization could offer a thorough hemodynamic and anatomic assessment and allow for targeted intervention.
A single center, retrospective cohort study was performed on all patients who underwent combined pre-Fontan CMR and cardiac catheterization from 10/2018-4/2022. These were then matched randomly by month of procedure to patients who underwent pre-Fontan catheterization only. A total of 37 combined patients and 40 cardiac catheterization only patients were included in the analysis. In the combined group, all patients were placed under general anesthesia and underwent the CMR prior to cardiac catheterization. The CMR protocol included cine SSFP function, cine SSFP anatomy, 3D MRA with gadolinium, and phase-contrast encoded velocity mapping of flows. In the combined group, an angiogram was routinely performed in the SVC with an aortagram performed at the discretion of the interventional cardiologist. Those who underwent a catheterization only also had angiograms performed in the IVC, descending aorta, and pulmonary vein(s).
Patients in the combined group had a longer duration of intubation (293 minutes, SD 51 minutes versus 193 minutes, SD 73 minutes) and anesthesia time (320 minutes, IQR 290-352 minutes versus 200 minutes, IQR 165-255 minutes). Time in the catheterization lab, procedure time (start of access to sheath removal), contrast dose per kilogram, and fluoroscopy time were all lower in the combined group. Radiation dose was also lower in the combined group, though this was not statistically significant. Patients who underwent a cardiac catheterization only were more likely to have an intervention performed (48% versus 19%) with the majority of these being aortopulmonary collateral occlusion. Fontan completion, cardiopulmonary bypass time, ICU length of stay, and post operative chest tube duration was not significantly different between groups.
CMR offers significant benefits as part of the pre-Fontan cardiac evaluation. In addition to evaluating systemic ventricular function more thoroughly than echocardiography, CMR also provides an objective assessment of AV valve regurgitation (via regurgitant fraction), can evaluate the lymphatic system, and allows quantification of aortopulmonary collateral burden. This study showed that CMR performed as part of the pre-Fontan cardiac catheterization can reduce case duration, iodinated contrast volume, and radiation exposure. Additionally, pre catheterization CMR allowed for more targeted interventions (especially aortopulmonary collateral occlusion) with objective data (elevated end diastolic pressure or 30% or greater collateral flow) determining intervention instead of the discretion of the interventional cardiologist. Using these guidelines, the authors showed that post-operative outcomes were similar between the groups.
