Novel technique to reduce the size of a Fontan Diabolo stent fenestration

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. Conclusion : 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. © 2010 Wiley‐Liss, Inc.     

Dyspnoea and exercise intolerance during cardiopulmonary exercise testing in patients with univentricular heart: The effects of chronic hypoxaemia and Fontan procedure

BACKGROUND: Patients with univentricular hearts have decreased exercisetolerance and may demonstrate exertional dyspnoea. It is notknown if chronic hypoxaemia exacerbates exercise intoleranceand contributes to symptomatic limitation. The extent to whichsurgical correction of a right-to-left shunt by a Fontan-typeprocedure can increase exercise tolerance by reducing arterialdeoxygenation is not well documented. The cardiopulmonary exerciseresponses and the symptomatic status in two groups of univentricularpatients, those who are cyanotic and those who are acyanoticwith Fontan-type circulation, were compared. METHODS AND FINDINGS: Cardiopulmonary exercise testing was performed in 10 univentricularpatients with rest or stress-induced cyanosis (age 30·5±2·3[SE] years; 5 men) who had palliative or no surgery and eightpatients (age 29·4±1·5 years; 4 men) withFontan-type circulation. Peak oxygen consumption was comparablein both groups of univentricular patients (21·7±2·5vs 21·0±1·9 ml. kg^–1 . min^–1,P=0·85) but was less than an age-matched group of 10healthy subjects (34·7±1·9 ml. kg^–1. min^–1, P<0·001 for both). Arterial oxygensaturation was 90·6% at rest in the cyanotic patientscompared with 95·1% in the Fontan patients (P<0·001)and at peak exercise, 66·2% compared with 90·5%(P<0·001). Using a modified Borg scale (0–10),the symptoms of dyspnoea and fatigue were also assessed duringexercise in the patient groups. The Borg scores for dyspnoeain the cyanotic and the corrected univentricular patients were,respectively, as follows: Stage 1: 0·5 vs 1·7;P=0·04; Stage 2: 1·8 vs 2·3, P=0·5;Stage 3: 3·0 vs 3·5, P=0·7; Peak Exercise:4·9 vs 4·8, P=0·9. In addition, the Borgscores for fatigue were: Stage 1: 0·4 vs 1·6,P=0·08; Stage 2: 2·0 vs 2·2, P=0·9;Stage 3: 3·0 vs 4·3, P=0·5; Peak Exercise:4·9 vs 5·4, P=0·5. The major limiting symptomat peak exercise was dyspnoea in four cyanotic patients comparedwith one in the Fontan group (Chi-square 0·982, P>0·10).The arterial oxygen desaturation at peak exercise in the cyanoticpatients limited by dyspnoea was not different from those limitedby fatigue (67·5±10·1% vs 66·7±13·7%,P=0·92). Exercise tolerance was also not related to thearterial oxygen saturation at peak exercise (r=0·47,P=0·17) in these patients. CONCLUSION: Despite correction with Fontan-type surgery, the exercise toleranceand symptoms of these univentricular patients remained similarto those who were cyanosed. Cyanotic patients have adjustedto chronic hypoxaemia and it does not appear to determine theexercise tolerance or the genesis of dyspnoea in these patients.Further randomized prospective studies are required to investigatethe long-term benefits of Fontan-type procedures in these patientson exercise tolerance, symptoms and prognosis.     

Late fenestration of the extracardiac conduit in a Fontan circuit by sequential stent flaring.

Recent Fontan circuits frequently involve an extracardiac conduit. We report on a new technique to create a late fenestration in such an extracardiac circuit by sequential flaring of a stent in the fenestration.     

Transcatheter fenestration of hemi-Fontan baffles after completion of Fontan physiology using balloon dilatation and stent placement

De novo transcatheter fenestration of hemi-Fontan baffles has not been previously described. The purpose of this report is to present our experience in such de novo transcatheter fenestration in two consecutive patients with absent fenestration in whom the hemi-Fontan baffle was the only direct access to the pulmonary venous atrium. Cathet. Cardiovasc. Diagn. 43:429–432, 1998. © 1998 Wiley-Liss, Inc.     

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.     

A new Amplatzer device to maintain patency of Fontan fenestrations and atrial septal defects.

This study evaluated use of Amplatzer fenestrated device to maintain patency of the Fontan fenestration and atrial septal defect. Fenestrations are routinely created in patients with lateral tunnel or extracardiac Fontan. Spontaneous closure of the fenestration can lead to Fontan circulation failure. Other patients without single-ventricle physiology may benefit from a small communication between the left and right atria for decompression if closure of the atrial septal defect leads to failure of a dysfunctional ventricle. Amplatzer septal occluder device was modified to create a fenestration through the disks. Three patients with modified Fontan and one patient with a large atrial septal defect underwent placement of the device by transcatheter technique. The device deployment was guided by transesophageal echocardiography. The procedure was successful in all patients. Contrast injection after placement revealed patent fenestration with free flow. Follow-up ranged from 3 months to 1 year. All devices were patent by transthoracic echocardiography. These preliminary results suggest that the Amplatzer fenestrated device can serve as a valuable tool in failing Fontan circulation and may help to avoid surgical intervention. More studies are needed to assess long-term efficacy of the device.     

Exercise capacity and impact of exercise training in patients after a Fontan procedure: a review

After a successful Fontan procedure, children and adolescents should improve their exercise capacity. However, several studies have shown that these children have a reduced maximal oxygen consumption compared with healthy children. The lower exercise performance in these patients was mainly explained by a reduced cardiorespiratory functional capacity. However, it has recently been reported that the lower exercise performance may also be related to altered skeletal muscle function. Moreover, exercise training had a beneficial impact on several parameters related to exercise tolerance in these patients. The main studies supporting these observations are reviewed, with a focus on the physiological adaptation and limitation of the exercise performance as well as the benefits of exercise training in patients after a Fontan procedure.     

Incidence and factors influencing the spontaneous closure of Fontan fenestration

Introduction: The Fontan operation is the final stage of single ventricle palliation in patients with complex congenital heart disease. Fenestration in the Fontan conduit, providing an atrial level right to left shunt, has been shown to reduce early postoperative morbidity. However, there is limited data on the long‐term fate of this fenestration. The aim of this study is to define the rate of spontaneous closure of the fenestration in the Fontan conduit and factors predictive of the fate of the fenestration.
Methods: This was a retrospective study reviewing the medical records of the patients who underwent fenestrated Fontan operation at our center. Preoperative, intraoperative and postoperative variables including the status of the Fontan fenestration were extracted and analyzed.
Results: Of 67 patients included in the study, 15 (22%) had spontaneous closure of the fenestration. Of the remaining 52 patients, 11 (20%) had procedural closure of this fenestration (10 via cardiac catheterization and 1 via surgery) at a median duration of 3 months after the Fontan operation. Patients with higher preoperative pulmonary vascular resistance and a history of postoperative systemic venous thromboembolism had higher likelihood of having persistence of the fenestration with P value of .045 and .037, respectively.
Conclusions: The rate of spontaneous closure of the Fontan fenestration was 22% in our study. Elevated preoperative pulmonary vascular resistance and history of systemic venous thromboembolism are predictive of persistent Fontan fenestration.     

Usefulness of predischarge exercise electrocardiographic testing in detecting the late patency status of the infarct-related artery

Predischarge exercise electrocardiographic testing (PEET) represents a widely accepted clinical tool for prognostic and functional assessment of patients who experience an uncomplicated acute myocardial infarction (AMI). However, there are no data suggesting any relation between PEET results and patency status of the infarct-related artery (IRA). The aim of this study was to investigate whether ST and/or QT-dispersion (QTD) changes induced by a low-level PEET, after uncomplicated ST-elevation AMI, are related to the late patency status of the IRA. We prospectively evaluated 61 consecutive patients who had suffered a first uncomplicated ST-elevation AMI. All of them successfully carried out four stages of the modified Bruce protocol exercise testing before discharge, and thereafter were subjected to coronary angiography. Exercise-induced ST elevation and QTD shortening were found significantly more frequently in patients with persistently occluded IRA, as compared to patients with patent IRA (ST elevation 65% vs 27%, P = 0.006; QTD shortening 80% vs 29%, P 0.0001). The coexistence of the two variables predicted the presence of occluded IRA with a positive predictive value of 75%, whereas the absence of both predicted the patency of IRA with a negative predictive value of 100%. These results indicate that ST-elevation and QT-dispersion changes induced by a predischarge exercise testing after a first ST-elevation AMI may effectively predict the late patency status of the infarct-related artery.     

Percutaneous fenestration closure with problematic residual native atrial septum.

A variety of techniques have been utilized to close Fontan fenestrations. Among 20 patients who underwent a cardiac catheterization for fenestration closure, 3 patients had residual native atrial septum, forming an additional intermediate chamber on the pulmonary venous side of the fenestration. Three different methods were used to close these fenestrations.     

Prognostic value and diagnostic potential of cardiopulmonary exercise testing in patients with chronic heart failure

Cardiopulmonary exercise testing (CPET) is a well established technique for stratifying cardiovascular risk in patients with chronic heart failure (CHF). Important prognostic variables include a reduced peak oxygen uptake which has a central use in cardiac transplant selection, and the abnormal relation between minute ventilation (VE) and carbon dioxide production (VCO(2)), often referred to as the elevated VE/VCO(2) slope. We will discuss the pathophysiology of these abnormal responses to exercise in CHF, and how these are interpreted during CPET. The potential of CPET for diagnosing circulatory, respiratory, metabolic, musculoskeletal or mixed limitations is an emerging field of research. We will speculate on how CHF manifests during CPET, and clarify the pathophysiological basis of these exercise responses. To improve our understanding of the diagnostic value of CPET, further investigation is required by clinicians to develop reference ranges for CHF patients from a co-ordinated multicentre approach. The use of CPET technology is becoming increasingly prevalent in cardiology services, and it is likely that, in the future, CPET will take a more prominent role in guiding patient management provision.     

递增心肺运动试验的风险与防控

目的 探讨递增心肺运动试验中的危险信号及应采取的应对措施.方法 198例受试者进行心肺运动至症状自限,同步实时测定摄氧量、二氧化碳排出量,监测血氧饱和度、心电图和血压,慢性阻塞性肺疾病(COPD)患者于运动前后测定血气分析.结果 155例受试者运动至最大耐受量,43例因出现危险信号而终止运动.危险信号包括:血氧饱和度低于88%(14例);收缩压升高或降低(3例);心律失常(16例);缺血性ST-T改变(10例).COPD患者运动高峰时PaO2轻度降低,从(91.58±9.46)mm Hg降至(88.92±13.66)mm Hg,但差异无统计学意义,运动时的PaCO2较静态时轻度增高,分别为(43.05±3.16)mm Hg和(40.64±4.26)mm Hg,差异有统计学意义(P=0.003).结论 只要我们在运动试验中进行监测,出现危险信号时及时终止运动,运动试验对于多数患者还是一个安全的检查.     

Comparison of cardiopulmonary exercise testing variables in COPD patients with and without coronary artery disease

Background

Coronary artery disease (CAD) is a common concomitant condition and an important cause of morbidity and mortality in patients with chronic obstructive pulmonary disease (COPD). Since COPD and CAD can both independently cause reduced exercise capacity, it is reasonable to hypothesize that the combination of these diseases may compound the abnormalities observed during cardiopulmonary exercise testing (CPET). However, little is known about the impact of CAD on the CPET response in COPD patients. The aim of this study is to compare exercise capacity and gas exchange variables in COPD patients with and without CAD.

Methods

Fifty-four COPD subjects without CAD (COPDnoCAD) were matched to 54 COPD subjects diagnosed with CAD (COPD/CAD) according to age, gender, body mass index and severity of COPD. All subjects underwent resting pulmonary function and symptom-limited CPET.

Results

Comparing COPDnoCAD patients with COPD/CAD patients revealed that exercise capacity, as measured by % peak oxygen consumption (42 ± 16% vs 53 ± 19%, p = 0.002) and % peak wattage (23 ± 13% vs 32 ± 16%, p = 0.001), was significantly lower in COPD/CAD. Ventilatory response, as measured by VE/VCO₂ nadir (36 ± 9 vs 32 ± 5, p = 0.001), was significantly higher in COPD/CAD, with % peak VO₂ and VE/VCO₂ nadir correlating to % FEV₁ and inversely correlating with %DLCO.

Conclusion

COPD patients with CAD have significantly impaired CPET responses with lower exercise capacity and impaired gas exchange compared to COPD patients without CAD. These findings may affect the clinical interpretation of CPET data in COPD patients who have concomitant CAD.     

De novo fenestration of extra‐cardiac fontan goretex conduit assisted by inoue balloon

De novo fenestration of Goretex conduit of extra‐cardiac total cavopulmonary connection in the postoperative period is challenging, and is rarely reported. We report a 17‐year‐old boy with failing Fontan circuit in whom fenestration was created, aided by an Inoue balloon. © 2012 Wiley Periodicals, Inc.     

Transcatheter interventions in the early postoperative period after the Fontan procedure

Objective : To analyze the safety and clinical impact of interventional cardiac catheter procedures in the management of early postoperative problems after completion of an extracardiac Fontan procedure. Background : The mortality after Fontan procedure has consistently decreased over the last decade. The role of interventional catheterization to address early postoperative problems in this setting has not been studied systematically. Methods : Over a 9.7‐year period, 289 patients underwent an extracardiac fenestrated Fontan procedure with two early deaths (0.7%) and takedown in four (1.4%). Twenty‐seven patients (9.3%) underwent 32 interventional cardiac catheter procedures at a median interval of 12.2 (1–30) days. The median weight was 14.5 (13.5–25) kg. The case notes and procedure records were reviewed retrospectively. Results : Fontan pathway obstructions were treated in 11 patients with stent implantation with good results and no complications. Stent fenestration of the Fontan circulation was performed in 16 patients with one episode of transient hemiparesis and one episode of pericardial effusion. Three patients underwent initial balloon dilatation of branch pulmonary arteries or fenestration with little effect and underwent stent treatment 6 (5–9) days later. One patient had device closure of a large atrial fenestration. In one patient, residual anterograde pulmonary blood flow was occluded using a device. There were no deaths and in‐hospital course was improved in all. Conclusion : Interventional cardiac catheter procedures can be performed safely and effectively in the early postoperative period after Fontan completion to address hemodynamic problems. These techniques contribute significantly to achieve a very low mortality and address morbidity after Fontan completion. © 2010 Wiley‐Liss, Inc.     

Intracranial haemorrhage during exercise testing

We describe the occurrence of an intraparenchymal (thalamic)haemorrliage during a stress test in a hypertensive 52-year-oldman who had suffered from myocardial infarction 3 months earlier.Common causes of spontaneous haemorrhage, such as arteriovenousmalformation, aneurysms, neoplasm, bleeding disorders or vasculitiswere excluded. This single neurological complication was observedfrom among 8000 exercise tests performed in our Institute from1987 to 1993.