Trans-Catheter Interventions: New Horizons in Medical and Surgical Fontan...

Fontan-associated plastic bronchitis occurs in less than 2% of patients with Fontan circulation

Plastic bronchitis is characterized by proteinaceous lymphatic effluent into the tracheobronchial tree where there are connections between the lymphatic circulation and the airway

With evaporation of water content through breathing, characteristic fibrinous airway casts remain and may be expectorated in whole or in part

The incidence of fenestration thrombosis or stenosis early after the procedure and in short and mid-term follow-up is very high with bare metal stents, presumably from tissue invagination through the cells of the stent and tissue factor exposure to blood

Even on anticoagulation, thrombosis is pretty common with bare metal stents used for fenestration creation

Good procedures don't always mean much - one can do a good intervention in a complex population but it doesn't always mean you're going to change the ultimate clinical outcome

The Fontan population has a very high incidence of liver-related pathologies

Having obstruction in the inferior limb of the Fontan can be a real problem as it only serves to augment venous hypertension

A resting absence of gradient does not rule out the presence of hemodynamically meaningful obstruction

Left innominate vein obstruction can create opportunity for patients to present with either plastic bronchitis or protein-losing enteropathy, two diagnoses associated with very adverse clinical outcomes that have been shown increasingly to be associated with lymphatic pathology, especially by the group from Philadelphia

Secondary palliations (palliation of a palliation, the Fontan circuit) have limitations - they may not offer cure, may not even offer substantial benefits

Sometimes we're not able to test the hypothesis until we actually perform the intervention

The approach to transcatheter interventions must be taken from a multidisciplinary perspective - therapies have both medical and surgical considerations to future therapies, to the need for anticoagulation

Everything we do can have sequelae - it's really important to make sure that the multiple disciplines we use to care for these patients all understand and appreciate the implications of decision making and therapies

Stent in conduit equals thrombogenic behavior substrate

A 12-year-old young man being on Coumadin is not free (not without consequences)

Having seen many of these patients grow up and face symptoms increasing through their teenage years, it's worth being aggressive when there's anatomic deficiencies within the circuit

The fluid challenge protocol involves giving 15 cc per kilo with no limit of fluid volume rapidly via central access in about 2 minutes, then starting a timer with 5 minutes from the end of fluid challenge until repeat hemodynamic runs are measured

Fluid challenge is not performed if patients have overt diastolic dysfunction, defined as baseline EDP at resting EDP of greater than 15

Fluid challenge is not performed if patients have baseline Fontan pressure greater than 18 and/or repeated hospitalizations with heart failure to get volume off

We can safely take Gore-Tex tubes to at least 110% of their nominal diameter

Beyond 110% of nominal diameter, there is a bit of risk, but the risk is probably pretty subtle for moderate dilation (e.g., 18mm tube to 22mm)

There is always risk at the anastomosis where it's hard to necessarily cover that should a problem arise because hepatic vein enters very close

Gore-Tex tubes can be taken up to about 110% - the stiffness constant is very high and you cannot generate enough pressure in the balloon to stretch the Gore-Tex much more than about 110%

The risk of rupture is actually very low when dilating Gore-Tex conduits

There are few patients who have an undersized tube at placement and really require augmentation of the nominal diameter

Extracardiac conduits are three-dimensional structures that are not circular - if a 22mm tube measures 17mm in the frontal plane, it often measures 25mm in the lateral plane, and the cross-sectional area is just fine

It's important that there's a true stenosis, not just a non-circular shape, for us to want to treat conduit narrowing