Author + information
- Lindsay S. Rogers, MD and
- David J. Goldberg, MD⁎
- ↵⁎The Cardiac Center, The Children's Hospital of Philadelphia, 34th Street and Civic Center Boulevard, Philadelphia, Pennsylvania 19104
We thank the correspondents for their interest in our recent paper concerning post-operative outcomes after the Fontan operation (1). Our goal in reviewing our experience was to identify risk factors for morbidity and mortality at the time of Fontan surgery. Although the creation of a total cavopulmonary connection (TCPC) was performed as a single procedure for a number of years, that strategy was abandoned because of substantial morbidity and mortality with the combined procedure. It is now well established that creating a total cavopulmonary connection in 2 separate operations results in significantly improved outcomes. Indeed, in our cohort, more than 97% of subjects had a superior cavopulmonary connection (SCPC) before Fontan surgery.
With due respect to the correspondents, we posit that although ventricular unloading of the systemic ventricle does begin after SCPC, there remain substantial differences between the circulation after SCPC and the circulation after the Fontan operation. After SCPC, oxygen saturations remain significantly lower than normal, which may lead to the formation of systemic to pulmonary collateral vessels and may mitigate the impact of ventricular unloading. Further, after SCPC, venous flow from the inferior extremities returns to the heart in the usual fashion, whereas after the Fontan operation, all venous return, with the exception of fenestration flow, must traverse the pulmonary vascular bed. This likely has implications for the distribution of blood flow and may limit cardiac filling.
In this paper, we focused on early outcomes after the Fontan operation. An evaluation of outcomes over the course of the entire single ventricle palliative pathway would have to include the outcome after SCPC along with the outcome up until SCPC, which may include a Norwood type reconstruction, a systemic to pulmonary arterial shunt, a pulmonary arterial band, or close observation without surgical intervention. We do not believe that grouping SCPC with the Fontan operation is necessary or appropriate when evaluating the post-operative outcome of the Fontan operation itself. The physiological features after SCPC are different from those after the Fontan operation, and we believe that the factors associated with outcomes for each procedure should be evaluated separately. Although our data do not describe an overall morbidity and mortality for the entire course of single ventricle palliation, they do provide important information regarding patient and procedural factors associated with short-term morbidity and mortality after the Fontan operation, information relevant to all patients being considered for total cavopulmonary connection. With regard to the long-term outcome after Fontan surgery, we agree that this is an important issue that warrants attention, but this review was focused on perioperative and early post-operative outcomes.
- American College of Cardiology Foundation