Protein-losing enteropathy after the Fontan operation: successful treatment by percutaneous fenestration of the atrial septum

Protein-losing enteropathy managed with percutaneous enlargement of a restrictive atrial septal defect

Protein-losing enteropathy is one of the most feared complications of the Fontan circulation. The diagnosis of protein-losing enteropathy in this setting should prompt a thorough investigation for the presence of a treatable hemodynamic impairment. In this report, we describe a complete reversal of protein-losing enteropathy following percutaneous enlargement of a restrictive atrial septal defect in a patient with a fenestrated lateral tunnel Fontan and severe mitral stenosis.

A potentially curative fetal intervention for hypoplastic left heart syndrome

Hypoplastic left heart syndrome (HLHS) encapsulates a spectrum of complex congenital cardiovascular malformations involving varying degrees of underdevelopment of the left-sided heart structures. However, despite improved survival rates since the introduction of staged surgical reconstruction, treatment options for HLHS remain palliative rather than curative. A major limiting factor in the development of definitive curative therapy for HLHS is an incomplete understanding of its pathogenesis. Currently, the aetiology HLHS is best conceptualised by the 'flow theory' of cardiogenesis, which states that normal cardiac development is reliant on the interrelationship of normal flow patterns of blood through the developing heart, and appropriate growth of the cardiac valves and myocardium. Thus, congenital cardiac malformations, such as HLHS, are thought to arise when these two processes are incorrectly coupled in utero. The rationale for the hypothesis proposed herein rests upon the flow theory of cardiogenesis. Morphological studies of HLHS indicate that, although underdeveloped, all left-sided cardiac structures are present and anatomically correct. Further, of the various structural abnormalities that can occur within the spectrum of HLHS, the presence of a ventricular septal defect (VSD) is rare. The rarity of a VSD within the morphological spectrum of HLHS suggests the syndrome may not develop in the presence of a functionally significant VSD. Presumably, the presence of a functional VSD establishes a communication between the two ventricles during cardiac development, and preserves the normal pressure-flow-dependent growth of the left ventricular (LV) myocardium, despite inflow/outflow valve defects. It is proposed that surgical creation of a VSD in utero will 'rescue' the LV of hearts with left-sided valvular deformities that render them susceptible to the development of HLHS later in gestation. In evaluating this hypothesis, potential techniques for surgical creation of a VSD in utero are offered. These techniques are based on already established catheter-based in utero interventions, and conventional postnatal percutaneous procedures for VSD creation. Further discussion is also offered on techniques to avoid, and manage, potential complications (i.e. conduction system damage) of the proposed technique(s). Finally, if VSD creation in utero is indeed practically feasible, and successfully establishes the hypothesised hemodynamic and myocardial growth normalisation within the abnormally developing LV, the clinical implications are profound. This procedure may hold a potential cure for almost every sub-type of HLHS.

Fontan Procedure: old lessons and new frontiers

The Fontan procedure is an operation created for patients with single ventricular physiology. These patients have the potential to survive well into adulthood, however new problems can arise. Various topics, including physiological constraints, patient care, morbidity and clinical outcomes are discussed. The aim of this review is to identify current topics within the care of the Fontan patient population for the physician not comfortable with their unique physiology and complications.

Insights After 40 Years of the Fontan Operation

Fontan’s visionary operation and its modifications over the ensuing decades have re-established nonturbulent flow and substantially reduced cyanosis for patients with severe hypoplasia of one ventricle. However, a long list of largely unexpected sequelae has emerged over the last 40 years. Although it is not difficult to understand how care providers could become discouraged, a number of myths have arisen, which we will attempt to dispel with real-world counterexamples as well as with lessons learned from other disciplines: evolutionary, developmental, and computational biology. We argue that distinctive biochemical abnormalities pointing to dysfunction in multiple organs, including the largest organ system in the body, the endothelium, occur long before grossly observable changes in cardiac imaging can be recognized. With a rational redesign of both our surveillance scheme and our wellness strategies, we hope that Fontan survivors and their families, as well as physicians, nurses, and therapists, will see why Fontan’s principle remains just as vibrant today as it was in 1971.

[Medium-term management of protein-losing enteropathy of cardiac origin unresponsive to medical therapy in a patient awaiting heart transplantation]

Protein-losing enteropathy is characterized by excessive leaking of serum proteins into the gastrointestinal tract, as a result of disease progression in several diseases. We report the case of a 17-year-old-woman with hypoproteinemia, generalized edema and serosal effusions diagnosed as protein-losing enteropathy due to right ventricular failure secondary to previous surgical damage. All previously described therapies were ineffective in curing or relieving the disease or its symptoms, and the patient was listed for heart transplantation. During the 7-month period on the waiting list, the patient was managed as an outpatient, with fortnightly albumin infusions and intravenous furosemide administration, which allowed her a better quality of life during that period, avoiding further admissions.

Results of transcatheter Fontan fenestration to treat protein losing enteropathy

Transcatheter fenestration to create an interatrial communication has been used to treat patients with protein losing enteropathy (PLE) after Fontan operation. No systematic data have been reported assessing the results of this procedure. Our institutional database was queried to identify patients after Fontan operation who had transcatheter fenestration to treat PLE. Clinical notes, laboratory data, echocardiograms, and cardiac catheterization data were reviewed. From 1995 to 2005, 16 transcatheter fenestration procedures were performed in seven patients. Median age at fenestration was 18 years (range 13-41 years). Median duration of follow-up was 3.6 years (range 0.2-10.4 years). Techniques for fenestration included blade/balloon septostomy, stent placement, Amplatzer-fenestrated ASD device, and balloon dilation of previous stent. Size of the fenestration created was 5.2 +/- 1.1 mm. Systemic venous pressure remained unchanged after fenestration. Cardiac index increased significantly. Reduction of ascites and edema was noted after 9 of the 16 procedures. Ten of 16 (63%) of fenestrations spontaneously occluded. Three patients are free of ascites although recurrence of PLE occurred in all. One patient with a patent fenestration continues to have ascites. Two patients had Fontan takedown. One patient had conversion to a fenestrated extracardiac conduit Fontan and died postoperatively. The results of transcatheter Fontan fenestration are often disappointing. Maintaining fenestration patency is difficult. Even after "successful" fenestration, resolution of PLE may be incomplete and recurrences have occurred in all. Early consideration should be given to Fontan takedown or cardiac transplant in severely symptomatic patients with PLE who do not respond to fenestration. Transcatheter fenestration may be a bridge to a definitive procedure.

New Technique for Fenestration of the Interatrial Septum

Achieving controlled flow between the systemic and pulmonary venous circulations is desirable in many complex congenital heart diseases. This includes the Fontan circulation, primary pulmonary hypertension, double inlet ventricles, or hypoplastic left heart with obstruction to the atrioventricular valve. As no specific device is available for this purpose, we developed a balloon-mounted stent technique to achieve a predetermined-sized fenestration of an atrial baffle in a patient with Fontan circulation. The details of the technique are described.

Late complications associated with the Fontan circulation

The recent significant reduction in operative mortality associated with surgical completion of the Fontan circulation is clearly multi-factorial. Better understanding of the fundamental physiological and anatomical issues have led to refinements in operative technique, early neutralization of potential risk factors, widespread use of a staged approach, and selective application of the concept of fenestration or incomplete partitioning. While further reduction of operative mortality is important, and may be anticipated in the future, major emphasis now must be placed on optimizing functional outcome, and understanding and managing the late complications associated with the unique physiology produced by the Fontan circulation.

Modified technique of stent fenestration of the atrial septum

OBJECTIVES

To develop a modified technique for stenting the atrial septum in the treatment of patients with a failing Fontan operation or pulmonary hypertension.

SETTING

Two tertiary referral centres.

STUDY DESIGN

Prospective collaborative clinical study.

PATIENTS AND METHODS

A stent was mounted on a standard valvoplasty balloon catheter which was constricted to a predefined diameter by a loop created from a temporary pacing wire. Full balloon inflation created a diabolo shaped stent configuration. The technique was employed in 12 consecutive patients to relieve symptoms of a failing Fontan circulation (n = 6) or severe pulmonary hypertension (n = 6).

RESULTS

Ex vivo studies confirmed that a diabolo shaped stent configuration could be achieved using the above technique. Transcatheter stent implantation was successful in all 12 patients. All six Fontan patients showed significant clinical improvement. Right atrial pressure decreased from (mean (SD)) 16.8 (2.5) to 13.7 (1.9) mm Hg (p < 0.05), and arterial oxygen saturation from 92.8 (1.8)% to 82.7 (3.8)% (p < 0.01). Six patients underwent successful stent fenestration for treatment of pulmonary hypertension. All stents were patent and stable at the most recent follow up (mean 1.75 (1.05) years). No early or late stent related complications were encountered.

CONCLUSIONS

This new technique allows placement of a diabolo shaped stent with a predefined diameter across the atrial septum. The diabolo shape increases stent stability, facilitates recrossing of the stent during future catheter interventions, and ensures medium term stent patency.

Fenestrated Amplatzer device for percutaneous creation of interatrial communication in patients after Fontan operation

A customized Amplatzer septal device with a 5 mm fenestration was used to create an interatrial communication in two patients with previous Fontan operation and clinical indication for fenestration. At follow-up, device fenestration was occluded in both patients. In both patients, the device fenestration was reopened and patency maintained by placement of two stents within the communicating channel.

Fenestration of the Fontan baffle: Benefits and complications

Using a baffle fenestration or adjustable atrial septal defect in a modified Fontan operation is now a common practice. Hemodynamic benefits include increased cardiac index and systemic oxygen transport, as well as lower systemic venous pressure. The incidence and duration of pleural effusions is also reduced by this approach. Potential complications include those associated with the closure mechanism (snare or umbrella) as well as the possibility of paradoxical embolism. This review addresses our current understanding of the risks and benefits of this procedure. Copyright 1998 by W.B. Saunders Company

Protein-Losing Enteropathy and Gastropathy

The diagnosis of protein-losing enteropathy (PLE) should be considered in all patients with hypoalbuminemia and edema without other known causes, and established by plasma alpha(1)-antitrypsin (alpha(1)-AT) clearance or nuclear studies. The therapy for PLE should focus principally on the treatment of the underlying disease after it has been identified. Therapeutic goals should include improvement of hypoalbuminemia, edema, and lymphopenia. The existing primary literature for therapy of PLE syndromes consists mainly of case reports and expert opinions, subject to substantial reporting bias and unknown rates of spontaneous remission; the rarity of and the diversity among this set of diseases make future large randomized trials unlikely. Therapeutic choices, therefore, must involve clinical acumen, empiricism, and understanding of the pathophysiology of the underlying disease process, and must be tailored to each individual patient's syndrome. Dietary interventions including hypolipidic, high-protein regimens, supplemented by medium-chain triglycerides (MCTs), are extremely useful, particularly in protein loss due to increased lymphatic pressure. Corticosteroids can be very useful in certain cases of PLE (though not without substantial long-term toxicity) when clinical serologic or histologic markers of inflammatory disease are present. Octreotide is a well tolerated drug that has been demonstrated to improve PLE in some patients, and is worth consideration. Octreotide is a well tolerated drug that has been demonstrated to improve PLE in some patients, and is worth consideration. Surgery finds its best role in treating gastrointestinal protein loss from neoplasia, inflammatory bowel disease, and hypertrophic gastritis. Most other PLEs are distributed too widely for surgical intervention. Protein-losing gastropathy (PLG) behaves somewhat differently from the general group of PLE, marked by excellent responses to elimination of Helicobacter pylori, antisecretory therapy, and surgical resection. Protein-losing enteropathy stemming from cardiovascular disease is best treated by medical or surgical cardiovascular interventions; however, some patients may respond to mucosa-directed therapy.

Use of heparin in the treatment of protein-losing enteropathy after fontan operation for complex congenital heart disease

Protein-losing enteropathy (PLE) is a serious complication of the Fontan operation and is associated with pronounced mortality. Medical management of PLE has been only partially successful. A recent report noted dramatic improvement in patients with PLE within 3 weeks of subcutaneous administration of heparin. We report a case of reversal of PLE with resolution of clinical symptoms and normalization of serum albumin, total protein, and fecal alpha1-antitrypsin values after several months of heparin treatment. Our findings substantiate those recently reported but suggest that reversal of PLE may necessitate more than a few weeks of heparin therapy.

Protein-losing enteropathy after the Fontan operation: an international multicenter study. PLE study group

OBJECTIVE

This multicenter study retrospectively analyzes the data on 114 patients with protein-losing enteropathy after Fontan-type surgery. Special attention was given to the different treatment strategies used and their effect on outcome.

METHODS AND RESULTS

In 35 participating centers 3029 Fontan operations were performed. The incidence of protein-losing enteropathy in the survivors was 3.7%. The median age at Fontan-type surgery was 8.2 years (range: 0.6 to 32.9 years). Median age at diagnosis of protein-losing enteropathy was 11.7 years with a median time interval between surgery and diagnosis of 2.7 years (range: 0.1 to 16.4 years). Most patients had edema (79%) and effusions (75%). Hemodynamic data revealed a mean right atrial pressure of 17 +/- SD 5.3 mm Hg with a cardiac index of 2.4 +/- 0.8 L/min/m2. Medical treatment only (n = 52) resulted in a complete resolution of symptoms in 25%, no improvement in 29%, and death in 46%. Surgical treatment (n = 52) was associated with relief of protein-losing enteropathy in 19%, no improvement in 19%, and death in 62%. In 13 patients 16 percutaneous interventions were performed. This resulted in symptomatic improvement after 12 interventions and no improvement after 4 interventions.

CONCLUSIONS

We conclude that the current treatment of protein-losing enteropathy after Fontan operation is associated with a very high mortality and morbidity rate. Preventive strategies and new therapeutic approaches are necessary.