Clinical outcome and improved survival in patients with protein-losing enteropathy after Fontan operation

Anitha John, et al.
From Mayo Clinic
JACC 2014;64(1):54-62.

Also see, Editorial JACC 2014;64(1):63-64.

Fontan - Hemodynamics

JACC Cardiovasc Imaging. 2014 Mar;7(3):215-24. doi: 10.1016/j.jcmg.2013.12.010. Epub 2014 Feb 13.

Geometric characterization of patient-specific total cavopulmonary connections and its relationship to hemodynamics.

Tang E1, Restrepo M2, Haggerty CM2, Mirabella L2, Bethel J3, Whitehead KK4, Fogel MA4, Yoganathan AP5.

Author information

• 1School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia.
• 2Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia.
• 3Westat, Rockville, Maryland.
• 4Division of Cardiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.
• 5Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia. Electronic address: ajit.yoganathan@bme.gatech.edu.

Abstract

Total cavopulmonary connection (TCPC) geometries have great variability. Geometric features, such as diameter, connection angle, and distance between vessels, are hypothesized to affect the energetics and flow dynamics within the connection. This study aimed to identify important geometric characteristics that can influence TCPC hemodynamics. Anatomies from 108 consecutive patients were reconstructed from cardiac magnetic resonance (CMR) images and analyzed for their geometric features. Vessel flow rates were computed from phase contrast CMR. Computational fluid dynamics simulations were carried out to quantify the indexed power loss and hepatic flow distribution. TCPC indexed power loss correlated inversely with minimum Fontan pathway (FP), left pulmonary artery, and right pulmonary artery diameters. Cardiac index correlated with minimum FP diameter and superior vena cava (SVC) minimum/maximum diameter ratio. Hepatic flow distribution correlated with caval offset, pulmonary flow distribution, and the angle between FP and SVC. These correlations can have important implications for future connection design and patient follow-up.

Post-Fontan thrombotic complications

J Am Coll Cardiol. 2013 Jan 22;61(3):346-53. doi: 10.1016/j.jacc.2012.08.1023. Epub 2012 Dec 12.

Factors associated with thrombotic complications after the Fontan procedure: a secondary analysis of a multicenter, randomized trial of primary thromboprophylaxis for 2 years after the Fontan procedure.

McCrindle BW, Manlhiot C, Cochrane A, Roberts R, Hughes M, Szechtman B, Weintraub R, Andrew M, Monagle P; Fontan Anticoagulation Study Group.

Source

Labatt Family Heart Centre, Department of Paediatrics, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada. brian.mccrindle@sickkids.ca

Abstract

OBJECTIVES:

The study sought to identify factors associated with increased risk of thrombosis after Fontan.

BACKGROUND:

The Fontan procedure is the culmination of staged palliation for patients with univentricular physiology. Thrombosis is an important complication after this procedure.

METHODS:

An international multicenter randomized controlled trial of acetylsalicylic acid versus warfarin for thromboprophylaxis after the Fontan procedure was conducted in 111 patients, and did not show a significant difference regarding thrombotic complications. We performed a secondary analysis of this previously published manuscript to identify factors associated with thrombosis in this population. Standardized prospective data collection included independent adjudication of all events.

RESULTS:

At 2.5 years after randomization, time-related freedom from thrombosis was 69% (all venous, no arterial events), with 28% of thrombosis presenting with clinical signs or events. Hazard of thrombosis was highest immediately after Fontan with a gradual increase in risk during late follow-up. In multivariable models, factors associated with higher risk of thrombosis were pulmonary atresia with intact ventricular septum (hazard ratio [HR]: 3.64, 95% confidence interval [CI]: 1.04 to 12.70, p = 0.04), pulmonary artery distortion (HR: 2.35, 95% CI: 0.96 to 5.73, p = 0.06), lower pre-operative unconjugated bilirubin (HR: 0.84 μmol/l, 95% CI: 0.72 to 0.99, p = 0.04), use of central venous lines for >10 days or until hospital discharge (HR: 17.8, 95% CI: 3.97 to 79.30, p < 0.001), and lower FiO(2) 24 h after the procedure (HR: 0.67/10%, 95% CI: 0.45 to 1.00, p = 0.06). Patients on warfarin who consistently achieved minimum target international normalized ratio levels or those on acetylsalicylic acid had a decrease in risk of thrombosis compared with patients who often failed to meet target international normalized ratio level (HR: 3.53, 95% CI: 1.35 to 9.20, p = 0.01).

CONCLUSIONS:

More favorable thromboprophylaxis strategies are needed in light of the difficulties in controlling warfarin therapy and the high prevalence of thrombosis in this population.

Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Comment in

• An aspirin a day... [J Am Coll Cardiol. 2013]

Original Fontan Operation

January 2012 issue of the journal:
(Note: Apparently, this image is meant for an article, to be published in April 2012 issue. So, further description in this issue about this figure).

Diabolo Stent - Fontan Fenestration Creation, Creation of Dumbell shape

Catheter Cardiovasc Interv. 2010 Nov 15;76(6):860-4.
Novel technique to reduce the size of a Fontan Diabolo stent fenestration.
Anderson B, Bhole V, Desai T, Mehta C, Stumper O.
Source
The Birmingham Children's Hospital, Birmingham, United Kingdom.

Abstract
OBJECTIVES:
To develop an effective catheter technique to reduce the size of a Diabolo stent fenestration in the failing Fontan circulation.

BACKGROUND:
Diabolo stent fenestration is employed by many centers in the treatment of the failing Fontan patient. With subsequent recovery, exercise tolerance may be impaired by significant desaturation secondary to the right to left shunt across the fenestration. Complete fenestration closure carries the risk of recurrence of the initial symptoms and, hence, reduction of the size of fenestration should be the preferred technique.

METHODS:
Twenty-eight patients with failing Fontan circulations (16 early and 12 late) underwent Diabolo stent fenestration for relief of symptoms. Five of these patients remained very limited by severe desaturation even at rest, after complete recovery from symptoms. Further cardiac catheterization with crimping/reduction of the size of the waist of the stent was carried out using a technique whereby a snare catheter was placed over the waist of the stent aided by an arterio-venous guidewire loop and a balloon catheter placed within the stent.

RESULTS:
All 5 patients had successful stent reduction with improvement in saturations, whilst still maintaining a small residual fenestration. No complications were encountered.

ONCLUSION:
This novel technique of reduction of a diabolo stent fenestration, in a failing Fontan circulation, offers the advantages of avoidance of implanting further devices in the circulation and the ability to redilate the stent should symptoms recur.

Copyright © 2010 Wiley-Liss, Inc.

Tricuspid Valve Implantation in Fontan Patient

Circulation: Cardiovascular Interventions. 2011;4:112-3.
Images in Cardiology























History:
Tricuspid Atresia - type 1c
(Tricuspid atresia, Normally-related Great Arteries, VSD, no PS)

14 yrs: Fontan-Bjork Operation (RA-RV Hancock Prosthesis, Closure of ASD and VSD)

24 yrs: Obstruction of Hancock prosthesis. Therefore, replaced with 23 mm Aortic Homograft

38 yrs: Complete Heart Block - Dual Chamber pacemaker (RV lead via homograft)

45 yrs: PLE, failure of medical therapy, Severe TR

47 yrs: Melody Valve in Tricuspid position (inside Aortic Homograft). Resolution of PLE

14 mo follow-up: No recurrence of PLE.

Modification to Extra-cardiac lateral tunnel Fontan - In situ pedicled pericardial tunnel.

JTCVS Volume 140, Issue 5, Pages 1076-1083 (November 2010)

In situ pericardial extracardiac lateral tunnel Fontan operation: Fifteen-year experience
Read at the 90th Annual Meeting of The American Association for Thoracic Surgery, Toronto, Ontario, Canada, May 1–5, 2010.

Nahidh W. Hasaniya, MD, PhDa, Anees J. Razzouk, MDa, Neda F. Mulla, MDb, Ranae L. Larsen, MDb, Leonard L. Bailey, MDa

Background
The study purpose is to evaluate the long-term outcome of the in situ pericardial extracardiac lateral tunnel Fontan operation.

Methods
From June 1994 to August 2009, 160 patients with single ventricle (boys, n = 96, 60%, median age = 39 months, mean weight 15.5 kg) underwent the pedicled pericardial extracardiac lateral tunnel operation. Patients' charts were reviewed for perioperative and long-term follow-up data, outcome, and mortality. The potential growth of these tunnels was evaluated.

Results
The main diagnoses included tricuspid atresia (n = 44, 27%); double-outlet right ventricle (n = 29, 18%), and hypoplastic left heart syndrome (n = 26, 16%). The mean follow-up was 6.5 ± 3.7 years (range: 0.1–15 years). There were 2 (1.3%) operative and 6 (3.7%) late deaths. Actuarial survival at 14 years was 93%. Early complications included prolonged effusions (n = 35, 22%), chylothorax (n = 5, 3.1%), readmissions (n = 35, 22%), cerebrovascular accidents (n = 8, 5%), contralateral phrenic nerve palsy (n = 1, 0.8%), and transient arrhythmias (n = 5, 3.1%). No pacemaker was needed. Late complications included tunnel stenosis (n = 3, 1.8%) managed with balloon dilatation and stenting in 2 patients and surgical revision in 1; tunnel thrombosis (n = 2, 1.2%) causing death in both patients; and protein losing-enteropathy (n = 4, 2.5%). Follow-up echocardiography of 10 patients showed laminar flow, no turbulence/gradient at the inferior vena cava and mid-tunnel levels. The diameter indexed to body surface area showed growth, reduction, or no change depending on flow demands.

Conclusions
The construction of the extracardiac lateral tunnel Fontan conduit using viable pedicled pericardium is a relatively simple, durable, and safe operation. Long-term follow-up confirms low morbidity and mortality. Fenestration is unnecessary in most patients. This viable tunnel adapts to physiologic flow demands.

Enalapril in Fontan - No significant advantage

Circulation 2010;122:333-40.

Double-blind trial.

Enalapril (target dose - 0.4 mg/kg/day) vs. Placebo

Enrolled 230 infants with single ventricle physiology

Followed up to 14 months of age

Primary end point: Weight at 14 months

185 completed trial

(Rest were lost to either withdrawal from trial or death/transplant - 13%)

Other measures: Height, Ross score, BNP, Bayley Scale of infant development & Ventricular ejection fraction.

Result: No difference between the two group in any of the parameters studied.

Death or Transplant occurred in 13% in either group.

Adverse reactions occurred in 88 of Enalapril group and 87 of Placebo group.