Results of the modified Fontan operation in adults

Life After Surviving Fontan Surgery: A Meta-Analysis of the Incidence and Predictors of Late Death

AIM

We now know that 20-40% of patients with a single ventricle will develop heart failure after the second decade post-Fontan surgery. However, we remain unable to risk-stratify the cohort to identify patients at highest risk of late failure and death. We conducted a systematic review of all reported late outcomes for patients with a Fontan circulation to identify predictors of late death.

METHODS

We searched MEDLINE, Embase and PubMed with subject terms ("single ventricle", "Hypoplastic left heart syndrome", "congenital heart defects" or "Fontan procedure") AND ("heart failure", "post-operative complications", "death", "cause of death", "transplantation" or "follow-up studies") for relevant studies between January 1990 and December 2015. Variables identified as significant predictors of late death on multivariate analysis were collated for meta-analysis. Survival data was extrapolated from Kaplan-Meier survival curves to generate a distribution-free summary survival curve.

RESULTS

Thirty-four relevant publications were identified, with a total of 7536 patients included in the analysis. Mean follow-up duration was 114 months (range 24-269 months). There were 688 (11%) late deaths. Predominant causes of death were late Fontan failure (34%), sudden death (19%) and perioperative death (16%). Estimated mean survival at 5, 10 and 20 years post Fontan surgery were 95% (95%CI 93-96), 91% (95%CI 89-93) and 82% (95%CI 77-85). Significant predictors of late death include prolonged pleural effusions post Fontan surgery (HR1.18, 95%CI 1.09-1.29, p<0.001), protein losing enteropathy (HR2.19, 95%CI 1.69-2.84, p<0.001), increased ventricular end diastolic volume (HR1.03 per 10ml/BSA increase, 95%CI 1.02-1.05, p<0.001) and having a permanent pacemaker (HR12.63, 95%CI 6.17-25.86, p<0.001).

CONCLUSIONS

Over 80% of patients who survive Fontan surgery will be alive at 20 years. Developing late sequelae including protein losing enteropathy, ventricular dysfunction or requiring a pacemaker predict a higher risk of late death.

Outcomes of Patients Undergoing Primary Fontan Operation Beyond First Decade of Life

OBJECTIVES

Studies on older patients undergoing primary Fontan operation (FO) are limited, with conflicting results. We review our experience with these patients beyond the first decade of life.

PATIENTS AND METHODS

Between January 2000 and December 2014, a total of 105 patients ≥10 years of age (mean 15.6 ± 4.9, range 10-31, median 15 years) underwent primary FO without a prior bidirectional superior cavopulmonary anastomosis (Bidirectional Glenn [BDG]). Mean preoperative New York Heart Association (NYHA) class was 2.2 ± 0.57.

RESULTS

Operative procedure was extra-cardiac FO in 62 patients (8 were fenestrated). Forty-three had a lateral tunnel FO (26 were fenestrated). There were 11 (10.5%) early deaths. Fourteen of the 94 early survivors experienced prolonged pleural effusions, 7 had arrhythmias, and 2 had thromboembolic events. Two patients underwent Fontan takedown. On univariate analysis, NYHA functional class III, mean pulmonary artery (PA) pressure ≥15 mm Hg, hematocrit ≥60%, preoperative ventricular dysfunction, and atrioventricular valve regurgitation (AVVR) were associated with early mortality. Median follow-up was 78 (mean 88.9 ± 6.3) months. In 94 survivors, 6 (6.4%) late deaths were encountered. At last follow-up, 81 (86.2%) survivors were in NYHA class I. Actuarial survival was 84.7% ± 3.7% at 5, 10, and 15 years.

CONCLUSION

Carefully selected adolescents and young adults can safely undergo the primary FO. However, persistent pleural effusions, arrhythmias, thromboembolic events, and the need for reoperation mandate regular follow-up in such patients. Preoperative NYHA functional class III, mean PA pressure ≧ 15 mm Hg, hematocrit ≥ 60%, ventricular dysfunction, and AVVR were associated with early mortality, suggesting that primary FO should be avoided in such patients.

Unsatisfactory Early and Late Outcomes After Fontan Surgery Delayed to Adolescence and Adulthood

The ideal age to perform the Fontan procedure is still unknown. The aim of this study is to determine outcomes after Fontan surgery delayed to adolescence and adulthood in Australia and New Zealand. Patients who had undergone a Fontan procedure at 15 years of age or older were identified in the 1133 patients registered in the Australia and New Zealand Fontan Registry until December 2012. A total of 45 patients underwent the following Fontan procedure at a median age of 18.3 years (16-21 years): 24 atriopulmonary connections, 10 lateral tunnel, and 11 extracardiac conduits. Hospital mortality was 13% (6 of 45). After a mean follow-up of 15.5 ± 9 years, there were 8 late deaths. Survival rates after 10, 20, and 25 years were 79% (95% CI: 64-89), 70% (95% CI: 51-83), and 70% (95% CI: 51-83), respectively. Freedom from Fontan failure (death, heart transplantation, Fontan takedown, protein-losing enteropathy, and poor functional status) after 10 and 20 years was 63% (95% CI: 47-76) and 35% (95% CI: 19-52), respectively. Patients with a single left ventricle had a lower risk of failure (hazard ratio = 0.25, 95% CI: 0.10-0.59; P = 0.002). Arrhythmias developed in 29 patients after a median of 0.1 years (0-9.3 years) and 10 required a permanent pacemaker. Freedom from all adverse events at 10 years was 30% (95% CI: 16-45). Outcomes of the Fontan procedure in adolescents and adults are poor, with disproportionately high hospital mortality and late adverse events. The Fontan procedure should not be delayed to adolescence and adulthood and should be performed electively in childhood.

Outcomes of adolescents and adults undergoing primary Fontan procedure

Patients who have undergone the Fontan procedure in later adolescence and adulthood represent a unique population at risk for significant morbidity and mortality. The optimal strategy for long-term management of such patients is unknown. The aim of this study was to evaluate outcomes of patients who had undergone Fontan surgery later in life, focusing on late survivorship, mode of death, and predictors of mortality. Eighty-eight patients were identified who had their initial Fontan operation from 1973 to 2007 at ≥15 years of age. A standardized tiered contact protocol was followed to capture the recent health status of each patient; the probability of survival was 83%, 71%, and 66% at 5, 10, and 15 years of follow-up, respectively. Despite focused efforts, the modes of death were not available in 48% of the patients. A prolonged intensive care unit stay at the time of operation was the single predictor of mortality (p = 0.0123). In conclusion, this investigation highlights the significant mortality that exists in patients who undergo a Fontan procedure later in life and the difficulties in achieving standardized medical follow-up for this high-risk group of patients.

Immediate results of bidirectional cavopulmonary anastomosis and Fontan operations in adults

The purpose of this study is to analyze the immediate results of bidirectional cavopulmonary anastomosis (BCPA) and Fontan operations performed in adults, and to reveal the risk factors. During the years 1983-2010, 681 consecutive patients underwent BCPA or a Fontan operation. Fifty-three of 681 patients were more than 18 years of age. Twenty-nine adults underwent BCPA and 24 underwent a Fontan operation. Immediate results of surgical treatment were followed during the hospital period. The average number of exceeded 'operability' criteria by Choussat et al. [Choussat A, Fontan F, Besse P, Vallot F, Chauve A, Bricaud H. Selection criteria for Fontan procedure. In: Anderson RH, Shinebourne EA, editors. Pediatric Cardiology. Edinburgh: Churchhill Livingstone, 1977:559-566] was significantly higher in patients from the BCPA group compared to the Fontan group (1.3±0.8 vs. 0.9±0.7, P=0.034). Hospital mortality after BCPA in adults was 6.9% (2/29) and did not differ from children (7.1%, 19/268), P=0.634. Hospital mortality after Fontan operation in adults was 8.3% (2/24) and did not differ from children (11.9%, 43/360), P=0.419. The frequency of non-lethal hospital complications was higher in patients after a Fontan operation. Patients from the Fontan group more frequently developed arrhythmias and prolonged pleural effusions. Preoperative regurgitation at atrioventricular valves was an independent risk factor for hospital mortality and morbidity after a Fontan operation. BCPA and Fontan operations performed in adults are accompanied by good immediate results and considerably improves patients' condition.

Update in adult congenital cardiac surgery

The number of grown-up patients with congenital heart disease (GUCH) is constantly increasing and will equal the number of children requiring surgery for congenital heart disease (CHD). Specialized centers dealing with the medical and paramedical problems of these patients are required. GUCH patients can be divided into the following groups: (1) patients with minor cardiac malformations presenting at adult age for first treatment; (2) patients presenting for correction as adults because they are either naturally balanced or were surgically palliated; (3) patients presenting for expected reoperations after correction in childhood; (4) patients requiring repair of residual defects after correction; (5) patients developing heart failure after correction or palliation of CHD requiring thoracic transplantation; and (6) patients developing acquired heart disease in addition to CHD. Special aspects of malformations frequently occurring in GUCH patients are discussed in detail. Acquired heart disease in this patient population is expected to increase in the coming decades as survivors of CHD grow old.

Improved early results with the Fontan operation in adults with functional single ventricle

BACKGROUND

A growing number of adults with functional single ventricles are presenting as candidates for first-time and redo-Fontan operations. This study describes the clinical presentation and early operative results of adults who have undergone Fontan modifications.

METHODS

Between July 1995 and April 2003, 23 patients (>18 years old) had Fontan operations. We retrospectively reviewed their perioperative courses.

RESULTS

Twenty-three Fontan operations (first-time [n = 8] and redo [n = 15]) were performed with no early or late deaths. No patient has required reoperation. One patient has been listed for orthotopic heart transplantation. The overall mean age is 23 years (18 to 41 years); mean follow-up, 30 months; median postoperative hospital stay, 8 days (4 to 34 days); and median duration of chest tube drainage, 4 days (2 to 12 days). The postoperative New York Heart Association (NYHA) functional class was improved in 22 of 23 patients. Eight first-time Fontan operations (7 of 8 nonfenestrated) were performed; lateral tunnel (n = 7) and extracardiac conduit (n = 1). Two patients had preoperative arrhythmias. New onset arrhythmias (ventricular tachycardia and sinus node dysfunction), requiring treatment, occurred in two patients. Fifteen redo-Fontan operations (all nonfenestrated) were performed; lateral tunnel (n = 5) and extracardiac conduit (n = 10). Fifteen patients had preoperative arrhythmias, thirteen of which had intraatrial reentry tachycardia (IART) and required antiarrhythmic medications. Concomitant intraoperative radiofrequency ablation (RFA) (n = 11) and cryoablation (n = 1) procedures were performed. In the immediate postoperative period, there was IART recurrence in five patients (post-RFA [n = 4] and postcryoablation [n = 1]). At latest follow-up, no patient is being treated with antiarrhythmic medications. Two patients had new onset atrial arrhythmias that required treatment.

CONCLUSIONS

The Fontan operation can be performed in adults with minimal morbidity and improved NYHA functional class. New onset arrhythmias requiring treatment are sources of perioperative morbidity. Complete arrhythmia resolution of the preoperative arrhythmia may not be achieved in the immediate postoperative period in redo-Fontan patients. However, modification (intraoperative radiofrequency ablation-right atrial debulking) of the atrial tachycardia circuits in the redo-Fontan patients can result in complete resolution of preoperative atrial tachyarrhythmias at early follow-up.

Anesthetic management of the adult patient with congenital heart disease

As the number of CHD repairs in adults continues to increase, these operations will be performed in a wider variety of institutions and systems. Unfortunately, not all of these centers will have an optimal environment for correcting CHD in adults. This type of surgery is best accomplished in a facility specifically designed for treating adults with CHD. Optimal care of these patients is provided by cardiologists who are trained and experienced in pediatric and adult cardiology, by surgeons who are trained and experienced in treating CHD, and by anesthesiologists who are experienced in caring for adults with CHD. Whatever the setting, cardiac anesthesiologists involved in these cases must be thoroughly aware of the anesthetic implications for the unique pathophysiology of each patient, and they must not rely on their "usual" expectations of either true pediatric CHD or acquired adult heart disease.

The modified Fontan procedure: early and late results in 132 adult patients

OBJECTIVE

The modified Fontan procedure, usually performed in children, is used for the treatment of anomalies with a single functional ventricle. We reviewed our experience with the modified Fontan procedure performed in the adult patient.

METHODS

Between October 1973 and May 2001, the modified Fontan procedure was performed on 132 adult patients (74 men, 58 women). Median age was 23 years (range, 18 to 53 years). Diagnoses included tricuspid atresia in 34 patients (26%), double-inlet left ventricle in 48 (36%), and complex lesions in 50 (38%). The majority of patients (89%) had at least one prior palliative procedure; the most common procedures were Blalock-Taussig shunt in 85 patients and Glenn anastomosis in 31.

RESULTS

Operations included an atriopulmonary connection in 74 patients, lateral tunnel in 27, intra-atrial conduit in 14, right atrium-to-right ventricle in 9, extra-cardiac conduit in 3, and other in 5. Overall early mortality was 8.3%. Mortality was 6.5% for operations performed after 1980. This is comparable to the mortality of the modified Fontan procedure performed in children during the same time interval at our institution. All 7 of the early deaths since 1980 occurred in the complex lesion group. Morbidity included prolonged pleural effusion in 36 patients, atrial arrhythmias in 25, reoperation for bleeding in 13, permanent pacemaker in 8, and stroke in 2. Mean follow-up was 9.1 years with a maximum of 21.2 years. Actuarial survival for early survivors was 89% (84,95), 75% (67,84), and 68% (58,79) at 5, 10, and 15 years, respectively. Freedom from late reoperation was 89% (83,95), 85% (78,93), and 80% (70,91) at 5, 10 and 15 years, respectively. The majority (90%) of present survivors were New York Heart Association class I or II at follow-up.

CONCLUSIONS

In properly selected adult patients with functional single ventricle, the modified Fontan procedure can be performed with early mortality similar to younger patients. Early mortality is more likely with complex lesions. The majority of late survivors have a good quality of life.

Anesthetic and perioperative outcome of teenagers and adults with congenital heart disease

OBJECTIVE

To compare the perioperative outcome of patients >or=13 years old undergoing surgery for congenital heart disease in a children's hospital by a dedicated congenital heart surgery and anesthesia team with procedure-matched younger control patients.

DESIGN

Retrospective medical record review study. From October 1997 to July 2000, medical records of all patients >12 years old requiring cardiopulmonary bypass were reviewed. A control group of patients <or=5 years old was reviewed, and 2 patients were matched to each older patient by diagnosis and surgical procedure. Data are reported as mean +/- SD. Older (study) patients were compared with younger (control) patients using t-test or chi square, with p <or= 0.05 significant.

SETTING

Medical school-affiliated tertiary-care children's hospital.

PARTICIPANTS

Patients undergoing congenital heart surgery.

MEASUREMENTS AND MAIN RESULTS

The study group (older patients) comprised 85 patients, and the control group (younger patients) comprised 170 patients. There were no intraoperative deaths. All major complications-cardiopulmonary resuscitation, neurologic injury, massive hemorrhage with sternotomy, femoral cannulation for emergent bypass, and severe episodes of hypotension on induction of anesthesia-occurred in older patients undergoing repeat sternotomy.

CONCLUSION

Mortality and major morbidity were low in both groups; however, all major intraoperative incidents occurred in older repeat sternotomy patients, suggesting increased perioperative risk for adverse outcomes in these patients.

The Fontan procedure in adults

SETTING

Tertiary adult congenital cardiac referral centre.

DESIGN

Retrospective cross sectional analysis.

OBJECTIVES

To report our 20 year experience with adult Fontan operations, and to compare late outcome in patients with single ventricle with definitive aortopulmonary or cavopulmonary shunt palliation.

PATIENTS AND MAIN OUTCOME MEASURES

Patients older than 18 years undergoing Fontan operation between 1 January 1982 and 31 December 1998 were identified. Mortality and late outcome were derived from hospital records. These patients were compared with a cohort of 50 adults with single ventricle who had not undergone a Fontan operation.

RESULTS

61 adults, median age 36 years (range 18-47 years), with a median follow up of 10 years (range 0-21 years) were identified. Actuarial survival was 80% at one year, 76% at five years, 72% at 10 years, and 67% at 15 years. Compared with before the Fontan operation, more patients were in New York Heart Association (NYHA) functional class I or II at the latest follow up (80% v 58%, p < 0.001). Systolic ventricular function deteriorated during follow up such that 34% had moderate to severe ventricular dysfunction at the latest follow up compared with 5% before Fontan (p < 0.001). Arrhythmia increased with time (10% before Fontan v 57% after 10 years, p < 0.001). Fontan patients had improved NYHA functional class, ventricular function, atrioventricular regurgitation, and fewer arrhythmias than the non-Fontan group at the latest follow up.

CONCLUSION

The Fontan operation in adults has acceptable early and late mortality. Functional class, systolic ventricular function, atrioventricular regurgitation, and arrhythmia deteriorate late after surgery but to a lesser degree than in non-Fontan patients with a single ventricle.

Analysis by mathematical model of haemodynamic data in the failing Fontan circulation

Several late complications jeopardize the clinical performance of recipients of the Fontan operation. The underlying causes have been referred to disturbed flow dynamics in the cavopulmonary connections. Presumably, the large pressure drops occurring in the inferior and superior connections play a pivotal role in the pressure level of the entire circulation, especially in the venous. To address this issue, we retrospectively reviewed catheterization data of six patients with failing Fontan circulation and compared them with those of six patients with functioning Fontan circulation. The impact on the systemic and pulmonary pressure of the increase in the cavopulmonary connection resistances was studied through a steady-state mathematical model of the univentricular closed-loop circulation. In the patients with failing Fontan, pressure in the venae cavae was found to be significantly higher, especially at the inferior cava (19.3 +/- 2.2 versus 12.5 +/- 2.3 mmHg) with the pressure drop at the inferior cavopulmonary connection significantly increased (4.7 +/- 3.1 versus 0.33 +/- 0.82 mmHg). The proposed mathematical model permits us to clearly relate the pressure increase in the venae cavae to an increased resistance in the cavopulmonary connections. Therefore, the present analysis confirms that, to avoid possible congestion of venous circulation, the definitive palliation of univentricular heart should not cause pressure drops at the cavopulmonary connections.

Influence of age (body size) on the Fontan circulation--analysis by a theoretical model

Among the original selection criteria for the Fontan operation, the recommended age at the time of surgery has been 4 years or older, but recent clinical data have indicated the feasibility of this procedure in younger patients. Because age may influence the properties of the systemic vascular bed, changes in systemic vascular resistance (Rs) and systemic vascular compliance (Cs) associated with physical development were quantified in 86 pediatric patients without known abnormalities of the systemic circulation, and the effects of age (body size) on Fontan circulation were then analyzed using an analytical model of the cardiovascular system. As the body surface area (BSA) of the patient decreased, Cs also decreased significantly (r=0.81, p<0.001). Based upon this relationship between BSA and Cs, the analytical model showed that the impedance (ventricular afterload) of the Fontan circulation significantly increased as Cs decreased with the decrease in BSA. Moreover, the increase in impedance in response to changes in heart rate or Rs was inversely proportional to the BSA. However, these findings were significant only when the BSA was below 0.3 m2. Small BSA, or a lower age, has minimal effects on the Fontan circulation until it comes close to the infant value, and thus the Fontan procedure may be feasible much earlier than formerly recommended when the hemodynamics are otherwise acceptable.

[A 49 year old patient with single left ventricular morphology who underwent surgical repair and good outcome ]

We report a 51-year-old patient, diagnosed with single left ventricle and anterior rudimentary chamber which was corrected by a Fontan procedure in 1997. The echocardiogram, Holter and pulmonary perfusion scintigraphy, isotopic ventriculography, magnetic resonance and blood tests performed during follow-up showed an uncomplicated postoperative course. The patient remains asymptomatic. We believe that this is the oldest case suffering from this anomaly who underwent surgical repair.

Is captopril useful in decreasing pleural drainage in children after modified Fontan operation?

We performed a retrospective cohort study to assess the relation between administration of angiotensin-converting enzyme inhibitors and duration of pleural drainage in the early postoperative period in patients who underwent a modified Fontan operation at our institution from 1990 through 1996. This study failed to show that administration of captopril decreased the duration of pleural drainage in patients after a modified Fontan operation.

The Fontan procedure in adults

BACKGROUND

A retrospective clinical study was performed to document the course of adult patients undergoing the Fontan procedure.

METHODS

Between 1982 and 1994, 21 adults aged 18 to 40 years (mean age, 27 +/- 7 years) underwent a Fontan procedure. Anatomic diagnosis was tricuspid atresia in 9, double-inlet left ventricle in 4, and various single ventricles in 8. Four underwent a right atria-right ventricle connection, 13 had a right atria-pulmonary artery connection, and 4 had a lateral-tunnel Fontan. Three of these 4 had a snare-adjustable atrial septal defect. Preoperative risk factors assessed were left ventricular end-diastolic pressure greater than 10 mm Hg, ejection fraction lower than 0.45, mean pulmonary artery pressure higher than 15 mm Hg, transpulmonary gradient greater than 10 mm Hg, pulmonary artery abnormalities, and atrioventricular valve regurgitation. Mean preoperative risk score was 1.6 /-1.1. Mean New York Heart Association class was 2.6 +/- 0.5.

RESULTS

The operative mortality rate was 5% (1/21). Six patients (30%) had a major complication, four being prolonged effusions. One patient was lost to follow-up; the remaining 20 have been followed for a mean of 7.4 +/- 3.8 years. At follow-up, mean New York Heart Association class was 1.7 +/- 0.5. There has been one late death (5%) at 9 2/3 years, which was probably due to ventricular arrhythmia. Three patients (16%) have required and survived reoperation. During follow-up, 7 patients (37%) have had development of atrial arrhythmias requiring medication, and 2 have been treated for ventricular arrhythmias.

CONCLUSIONS

These results indicate that properly selected adults can undergo the Fontan procedure with low morbidity and mortality. However, late-developing arrhythmias, need for reoperation, and decreasing ventricular function are serious problems that mandate careful follow-up.

Survival into adulthood of patients with unoperated single ventricle

Adult patients with double-inlet left ventricle and perfectly balanced circulation may survive into the sixth decade with good functional capacity and preserved ventricular function. This should be considered before such patients are referred for a Fontan repair.

The adult patient with congenital heart disease

In adults with congenital heart disease who are confronted with noncardiac surgery, perioperative risks can be reduced, often appreciably, when problems inherent to this patient population are anticipated. The first necessity is to clarify the diagnosis and to be certain that appropriate information is obtained from a cardiologist with adequate knowledge of congenital heart disease in adults. Physiology and anatomy can vary significantly among patients who superficially carry identical diagnoses. Elective noncardiac surgery should be preceded by clinical assessment including review of clinical and laboratory data and securing the results of necessary diagnostic studies. Preoperative assessment should be performed far enough in advance of the anticipated date of surgery to allow critical assessment of the data and potential discussions with colleagues. Appropriate cardiovascular laboratory studies to be obtained or reviewed include electrocardiograms, chest radiographs, echocardiograms, and cardiac catheterization data, which may include specialized intracardiac electrophysiologic testing. Congenital heart disease in adults is a new and evolving area of special interest and expertise in cardiovascular medicine. Multidisciplinary centers for the care of these patients are being developed. The 22nd Bethesda Conference recommended that these centers include among their consultants anesthesiologists with special expertise in managing patients with congenital heart disease. These anesthesiologists can have the option of serving either as the attending anesthesiologists when patients require noncardiac surgery or as consultants and resource individuals to other anesthesiologists.

Cardiopulmonary function in adult patients late after Fontan repair

OBJECTIVES

The clinical status and exercise assessment of adult patients late after the Fontan operation were reviewed to determine cardiovascular function.

BACKGROUND

The Fontan operation is the final operation for many patients with tricuspid atresia or a single ventricle. Follow-up reports describe most patients to be in Canadian Cardiovascular Society functional class I or II. Objective measures of cardiac performance in the pediatric age group have shown significant dysfunction.

METHODS

Forty-seven adult patients were seen late after the Fontan operation at the Toronto Congenital Cardiac Centre for Adults. Thirty of these underwent cycle ergometry to determine maximal exercise capacity. Maximal ventilation, maximal oxygen uptake and anaerobic threshold were determined from a ramp exercise protocol. Ejection fraction at rest and during exercise was measured with gated radionuclide angiography. Results were compared with those of eight normal volunteers. Results are given as mean +/- SD.

RESULTS

Thirty patients underwent cardiopulmonary exercise testing 6.7 +/- 3.9 years after a first Fontan operation. Clinically 93% were in functional class I or II. The Fontan group patients had a significantly lower maximal work load (548 +/- 171 vs. 1,094 +/- 190 kilopond-meters, p < 0.00001), anaerobic threshold (11.2 +/- 2.9 vs. 23.6 +/- 4.6 ml/kg per min) and maximal oxygen consumption (14.8 +/- 4.5 vs. 42.1 +/- 10.0 ml/kg per min). Systemic ventricular ejection fraction was lower at rest (38 +/- 12% vs. 58 +/- 7%) and during exercise (40 +/- 15% vs. 70 +/- 8%).

CONCLUSIONS

Despite a clinical impression of good function, by objective measures adult patients continue to have significant cardiovascular limitation late after the Fontan operation.

Reconsideration of criteria for the Fontan operation. Influence of pulmonary artery size on postoperative hemodynamics of the Fontan operation

BACKGROUND

The outcome of the Fontan operation largely depends on the selection of patients because this procedure is a physiological correction. Among the several selection criteria for the Fontan operation, the importance of adequate size of the pulmonary artery remains controversial. In this series, in order to clarify whether the pulmonary artery size is indispensable or not as one of the selection criteria for the Fontan operation, we considered the physiological meaning of pulmonary artery size and investigated how it influenced postoperative hemodynamics of the Fontan operation.

METHODS AND RESULTS

In congenital heart disease of decreasing pulmonary blood flow, 40 patients were examined for this analysis. Pulmonary artery indexes (cross-sectional area of the right and left pulmonary arteries divided by body surface area) were measured as the expression of pulmonary artery size, and the relations of pulmonary artery index (PAI) to pulmonary vascular resistance (Rp) and compliance (Cp) were studied. There was no significant correlation between PAI and Rp, whereas a significant correlation was found between PAI and Cp (r = .71, P = .001). Furthermore, Cp influenced postoperative hemodynamics of the Fontan operation by affecting the peak central venous pressure (pCVP) and total impedance, which was the afterload to the ventricle. Impedance increased abruptly when PAI was < approximately 100 mm2/m2.

CONCLUSIONS

The smaller pulmonary artery size causes more disadvantageous hemodynamics after the Fontan operation, with resultant effects of the rise in pCVP and the increase in afterload to the single ventricle.

Reconsideration of criteria for the Fontan operation. Influence of pulmonary artery size on postoperative hemodynamics of the Fontan operation

BACKGROUND

The outcome of the Fontan operation largely depends on patient selection because this procedure is a physiological correction. Among the several selection criteria for the Fontan operation, the importance of adequate size of the pulmonary artery remains controversial. To clarify whether or not pulmonary artery size is indispensable as one of the selection criteria for the Fontan operation, we considered the physiological importance of pulmonary artery size and investigated how pulmonary artery size influenced postoperative hemodynamics of the Fontan operation.

METHODS AND RESULTS

In congenital heart disease of decreasing pulmonary blood flow, 40 patients were examined for this analysis. Pulmonary artery indexes (cross-sectional area of the right and left pulmonary arteries divided by body surface area) were measured as the expression of pulmonary artery size, and the relations of pulmonary artery index (PAI) to pulmonary vascular resistance (Rp) and compliance (Cp) were studied. There was no significant correlation between PAI and Rp, whereas a significant correlation was found between PAI and Cp (r = .71, P = .001). Furthermore, Cp influenced postoperative hemodynamics of the Fontan operation by affecting peak central venous pressure and total impedance, which was the afterload to the ventricle. Impedance increased abruptly when PAI was less than approximately 100 mm2/m2.

CONCLUSIONS

The smaller pulmonary artery size is hemodynamically disadvantageous after the Fontan operation, with resultant rise in peak control venous pressure and increased afterload to the single ventricle.

The modified Fontan procedure: physiology and anesthetic implications

The modified Fontan operation has gained wide acceptance as a functional corrective procedure for patients with CHD with single ventricle physiology. Long-term survival and palliation of symptoms are excellent with most patients able to lead normal lives. The absence of a pulmonary contractile ventricle means that the single ventricle is responsible for perfusion of both the pulmonary and systemic circulations. Elevated systemic venous pressure is required to overcome PVR and this state of systemic venous hypertension has a significant impact on the anesthetic and postoperative care of these patients.

Hemodynamic evaluation before and after closure of fenestrated Fontan. An acute study of changes in oxygen delivery

BACKGROUND

Acute changes in hemodynamics and oxygen delivery accompanying temporary occlusion of atrial defects in 14 patients after a fenestrated Fontan procedure were evaluated at a median interval of 32 days after surgery to identify candidates for permanent transcatheter closure of their defects.

METHODS AND RESULTS

Patients ranged in age from 9 months to 33 years and in weight from 7.9 to 69 kg. Right atrial (RA), left atrial (LA), and aortic pressures, mixed venous (SmvO2) and aortic (SaO2) oxygen saturation, and whole-body oxygen consumption (VO2) were measured, and systemic blood flow (Qs), systemic oxygen transport (SOT), and oxygen extraction were calculated before and after occlusion. SmvO2, VO2, and RA pressures did not change, but SaO2 increased from 84 +/- 6% to 95 +/- 3% (p less than 0.05), and LA pressures fell from 5.1 +/- 3.6 to 3.7 +/- 2.2 mm Hg (p less than 0.05). Qs fell from 2.4 +/- 0.7 to 1.8 +/- 0.41.min-1.m-2 (p less than 0.05), SOT fell from 425 +/- 154 to 366 +/- 112 ml.O2.min-1.m-2 (p less than 0.05), and oxygen extraction increased from 0.40 +/- 0.12 to 0.46 +/- 0.13 (p less than 0.05). Only one patient did not undergo definitive closure of his defect because of a marked decrease in Qs and SOT with a significant rise in RA pressure.

CONCLUSIONS

Although delayed closure of an atrial defect in these patients improved morbidity and mortality, the complete separation of the venous and systemic circulations was accomplished at the expense of decreased Qs and oxygen delivery despite the improved level of arterial oxygenation. The resting levels of oxygen extraction are elevated and will be associated with decreased exercise capability. The long-term benefits of closure of these fenestrations are yet to be shown.

Early and late results of the modified Fontan procedure for double-inlet left ventricle: the Mayo Clinic experience

Between May 1974 and March 1989, 155 patients with double-inlet left ventricle had the Fontan procedure performed at the Mayo Clinic. Age at operation ranged from nearly 2 to 41 years (median 10). The operative mortality rate from 1974 through 1980 (39 patients) was 21%, but from 1981 through 1989 (116 patients) it was reduced to 9%. The 17 late deaths were secondary to reoperation (n = 8), progressive myocardial failure (n = 5), sudden arrhythmia (n = 3) and bleeding varices (n = 1). Neither operative nor late mortality rate was significantly related to age at operation. At follow-up of 6 months to 11 years (mean 4.9 years) in 111 patients, 88% were in good or excellent condition and 12% were in fair or poor condition. The Fontan operation can be performed with a mortality risk of less than 10% in properly selected patients with double-inlet left ventricle. Late results are encouraging when contrasted with the clinical course of patients before this operative approach was utilized.

Electrophysiologic findings after Fontan repair of functional single ventricle

Cardiac arrhythmias are well recognized sequelae of the Fontan operation for complex congenital anomalies. In this study the electrophysiologic effects of the Fontan procedure were evaluated in 30 patients who underwent cardiac catheterization with electrophysiologic study 1.9 +/- 1.3 years (mean +/- SD) after modified Fontan repair for functional single ventricle. Abnormalities of sinus node or ectopic pacemaker automaticity were detected in 50% (15 patients) by determination of a prolonged corrected sinus node or pacemaker recovery time. Total sinoatrial conduction time was prolonged in 50% of the patients with normal sinus rhythm. Sinus node or ectopic atrial pacemaker function was entirely normal in only 43% of patients. The predominant atrial rhythm was normal sinus in 70% and ectopic atrial or junctional in 30%. Abnormalities of atrial effective and functional refractory periods were noted in 43% of patients and were most pronounced at faster paced cycle lengths. Atrial endocardial catheter mapping revealed intraatrial conduction delays between adjacent sites in 76% of the patients tested and in eight of nine patients with inducible intraatrial reentry. Programmed atrial stimulation induced nonsustained supraventricular arrhythmias in 10% of the 30 patients and sustained arrhythmias in 27%. Intraatrial reentry was the most common inducible arrhythmia and was present in seven of the eight patients with sustained and two of the three patients with nonsustained atrial arrhythmias. Atrioventricular conduction abnormalities were noted in 10% (three patients). No patient had inducible ventricular arrhythmias with programmed ventricular stimulation. The electrophysiologic findings after Fontan repair include abnormal sinus node function, prolonged atrial refractoriness, delayed intraatrial conduction and inducible atrial arrhythmias.(ABSTRACT TRUNCATED AT 250 WORDS)

The modified Fontan operation for children less than 4 years old

Of 500 patients who had a modified Fontan operation at this institution between 1973 and 1987, 54 (33 boys and 21 girls) were less than 4 years old. This retrospective study related preoperative clinical and hemodynamic data to subsequent survival. Twenty patients less than 4 years old had tricuspid atresia, 13 had double inlet ventricle and 21 had other complex heart defects. There were 14 early deaths (less than 30 days after operation) and 6 late deaths. Multivariate analysis of survival for the entire group of 500 patients revealed the following factors to be significantly associated with poorer survival: absence of tricuspid atresia (p = 0.011), asplenia (p less than 0.001), age less than 4 years at operation (p = 0.042), atrioventricular valve dysfunction (p = 0.017), early calendar year of operation (p less than 0.001) and the presence of either one or more of the following: left ventricular ejection fraction less than 60%, mean pulmonary artery pressure greater than 15 mm Hg and pulmonary arteriolar resistance greater than 4 U.m2 (p less than 0.001). On the basis of this study of 500 patients, age less than 4 years at operation appears to be an independent risk factor for poorer survival after the modified Fontan operation.

Predictors of rhythm disturbances and subsequent morbidity after the Fontan operation

The electrocardiographic, hemodynamic and surgical data of 30 patients who underwent a Fontan operation between 1977 and 1986 were retrospectively reviewed to identify the incidence and predictors of immediate and late postoperative arrhythmias and associated morbidity in long-term survivors. Of 4 patients who died less than 1 year after operation (mortality 13%), 1 death was related to an arrhythmia. Three patients were not in sinus rhythm before operation and were excluded from the statistical analysis that examined predictors of arrhythmias. The remaining 23 long-term survivors have been followed 6.3 +/- 2.6 years (mean +/- standard deviation) since surgery and all remain in New York Heart Association functional class I or II. Ten patients (43%) developed immediate postoperative arrhythmias (less than or equal to 30 days) whereas 11 (48%) had late arrhythmias. With up to 10.7 years of follow-up, the proportion of patients free from late arrhythmias continues to decline. Arrhythmias included bradyarrhythmias, atrial tachyarrhythmias, the tachy-brady syndrome and supraventricular ectopic activity. Immediate postoperative arrhythmias predicted late arrhythmias (p = 0.022). The preoperative electrocardiogram was the only variable useful in predicting both immediate and late postoperative arrhythmias. A more negative P-wave deflection in lead V1 (-2.4 +/- 0.7 vs -1.4 +/- 1.2 mV, p = 0.02) predicted patients with immediate postoperative arrhythmias, whereas both greater P-wave duration and a more negative deflection in this lead predicted late arrhythmias (103 +/- 14 vs 83 +/- 20 ms, p = 0.01, and -2.5 +/- 0.8 vs -1.3 +/- 1.0 mV, p = 0.005, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)