**6.6 Protein loosing enteropathy**

Protein losing enteropathy (PLE) is a grave long-term complication of Fontan with a prevalence of 11.1% in older types of Fontan [85, 97]. However, the incidence appears to have come down to 1.2% with staged TCPC [85, 98]. The reason for development of PLE is not understood. Intestinal protein loss secondary to lymphatic distension which in turn may be due to elevated pressure in systemic veins is considered to be a pathogenic mechanism. But, PLE has been seen even in patients with "normal" Fontan circuit pressures. Therefore, the true cause of PLE remains a mystery. The symptoms and signs of PLE are diarrhea, edema, ascites, and/or pleural effusions. Laboratory abnormalities include reduced serum albumin and elevated fecal alpha-1 antitrypsin levels. The PLE diagnosis may be confirmed with technetium 99m-labeled human serum albumin scintigraphy [99].

Because of high mortality rate seen with PLE, speedy diagnosis and implementing aggressive management strategies are important [85]. At first, supportive therapy such as medium-chain triglycerides diet, infusion of intravenous albumin, and replacement of immunoglobulins should be undertaken. Obstructive lesions in the Fontan pathway should be scrutinized, and aortopulmonary connections should be screened for. If identified, they should be treated with appropriate transcatheter measures. Surgical therapy is indicated if they cannot be adequately addressed with transcatheter intervention. A variety of other treatment regimens, including prednisone, elementary diet, calcium replacement, regular high-molecular-weight heparin, low-molecular-weight heparin, somatostatin, high-dose spironolactone, sildenafil, and resection of localized intestinal lymphangiectasia, have been utilized in the past with varying degrees of success [85].

### **Figure 13.**

*(a) Selected frame from a left innominate vein (L inn) cineangiogram in posteroanterior view demonstrating an anomalous vein (AV) opacifying the atrial mass (not marked). (b) Following occlusion with Gianturco coil (arrow), the AV is completely occluded and the systemic arterial saturation improved (Reproduced from [88]).*

**145**

**Figure 15.**

**Figure 14.**

*Fontan Operation: A Comprehensive Review DOI: http://dx.doi.org/10.5772/intechopen.92591*

*(A) Selected frame from a cineangiogram in lateral view with the catheter positioned at the superior vena cava/azygos junction illustrating a fistula which results in opacification of the left atrium (LA). (B) The fistula was occluded with an Amplatzer vascular plug (arrow—AVP) with some residual flow. (C) Follow-up* 

*(A) Selected cine frame from an internal mammary artery (IMA) cineangiogram in the lateral view, demonstrating multiple small collateral vessels arising from the pericardiophrenic (PCP) branch, which resulted in a significant levophase (not shown). (B) Following occlusion with a Gianturco coil (C), there is* 

*complete occlusion of this vessel (Reproduced from [95]).*

*SVC injection shows complete occlusion by the AVP (Reproduced from [96]).*

### **Figure 14.**

*Advances in Complex Valvular Disease*

**6.6 Protein loosing enteropathy**

vessels are shown in **Figures 13**–**16** [88, 95, 96].

in the past with varying degrees of success [85].

Systemic arterial to pulmonary arterial (or venous) collateral vessels produce left ventricular volume overload. These abnormal vessels should be transcatheteroccluded with coils, vascular plugs, and ductal occluding devices depending upon the size and accessibility. Examples from the author's experience of occluding these

Protein losing enteropathy (PLE) is a grave long-term complication of Fontan with a prevalence of 11.1% in older types of Fontan [85, 97]. However, the incidence appears to have come down to 1.2% with staged TCPC [85, 98]. The reason for development of PLE is not understood. Intestinal protein loss secondary to lymphatic distension which in turn may be due to elevated pressure in systemic veins is considered to be a pathogenic mechanism. But, PLE has been seen even in patients with "normal" Fontan circuit pressures. Therefore, the true cause of PLE remains a mystery. The symptoms and signs of PLE are diarrhea, edema, ascites, and/or pleural effusions. Laboratory abnormalities include reduced serum albumin and elevated fecal alpha-1 antitrypsin levels. The PLE diagnosis may be confirmed with

Because of high mortality rate seen with PLE, speedy diagnosis and implement-

*(a) Selected frame from a left innominate vein (L inn) cineangiogram in posteroanterior view demonstrating an anomalous vein (AV) opacifying the atrial mass (not marked). (b) Following occlusion with Gianturco coil (arrow), the AV is completely occluded and the systemic arterial saturation improved (Reproduced from [88]).*

ing aggressive management strategies are important [85]. At first, supportive therapy such as medium-chain triglycerides diet, infusion of intravenous albumin, and replacement of immunoglobulins should be undertaken. Obstructive lesions in the Fontan pathway should be scrutinized, and aortopulmonary connections should be screened for. If identified, they should be treated with appropriate transcatheter measures. Surgical therapy is indicated if they cannot be adequately addressed with transcatheter intervention. A variety of other treatment regimens, including prednisone, elementary diet, calcium replacement, regular high-molecular-weight heparin, low-molecular-weight heparin, somatostatin, high-dose spironolactone, sildenafil, and resection of localized intestinal lymphangiectasia, have been utilized

technetium 99m-labeled human serum albumin scintigraphy [99].

**144**

**Figure 13.**

*(A) Selected frame from a cineangiogram in lateral view with the catheter positioned at the superior vena cava/azygos junction illustrating a fistula which results in opacification of the left atrium (LA). (B) The fistula was occluded with an Amplatzer vascular plug (arrow—AVP) with some residual flow. (C) Follow-up SVC injection shows complete occlusion by the AVP (Reproduced from [96]).*

### **Figure 15.**

*(A) Selected cine frame from an internal mammary artery (IMA) cineangiogram in the lateral view, demonstrating multiple small collateral vessels arising from the pericardiophrenic (PCP) branch, which resulted in a significant levophase (not shown). (B) Following occlusion with a Gianturco coil (C), there is complete occlusion of this vessel (Reproduced from [95]).*

### **Figure 16.**

*(A) Selected cine frame from a right subclavian artery (RSA) cineangiogram showing branches (white arrows) of the thyrocervical (TC) trunk which supplied a number of small vessels, giving a good degree of levophase. (B) Complete occlusion occurred following the implantation of a Gianturco coil (C) (Reproduced from [95]).*

Following a short trial of any of the above treatment modes, largely on the basis of the cardiologist's preference, a more definitive treatment methods such as lessening the conduit pressure by creating a fenestration between the conduit and the atrium [99–101], converting atriopulmonary type of Fontan to TCPC [87, 102, 103], instituting sequential atrioventricular pacing [104, 105], and performing cardiac transplantation [106–108] should all be considered. Again, it is essential to emphasize that timely treatment should be instituted as soon as PLE is identified [85]. Fortunately, the need for use of these methods has progressively diminished since the wide use of staged TCPC.
