Moderate altitude is not associated with adverse postoperative outcomes for patients undergoing bidirectional cavopulmonary anastomosis and Fontan operation: a comparative study among Denver, Edmonton, and Toronto

Cardiovascular Outcomes in Fontan Patients With Right vs Left Univentricular Morphology: A Multicenter Study

Background

There is a paucity of data on long-term outcomes after Fontan palliation in patients with a dominant morphological univentricular right (uRV) vs left (uLV) ventricle.

Objectives

The purpose of this study was to compare the incidence of atrial arrhythmias, thromboembolic events, cardiac transplantation, and death following Fontan palliation in patients with uRV vs uLV.

Methods

The Alliance for Adult Research in Congenital Cardiology conducted a multicenter retrospective cohort study on patients with total cavopulmonary connection Fontan palliation across 12 centers in North America. All components of the composite outcome, that is, atrial arrhythmias, thromboembolic events, cardiac transplantation, and death, were reviewed and classified by a blinded adjudicating committee. Time-to-event analyses were performed that accounted for competing risks.

Results

A total of 384 patients were followed for 10.5 ± 5.9 years. The composite outcome occurred in 3.7 vs 1.7 cases per 100 person-years for uRV (N = 171) vs uLV (N = 213), respectively (P < 0.001). In multivariable analyses, uRV conferred a >2-fold higher risk of the composite outcome (HR: 2.17, 95% CI: 1.45-3.45, P < 0.001). In secondary analyses of components of the primary outcome, uRV was significantly associated with a greater risk of cardiac transplantation or death (HR: 9.09, 95% CI: 2.17-38.46, P < 0.001) and atrial arrhythmias (HR: 2.17, 95% CI: 1.20-4.00, P = 0.010) but not thromboembolic events (HR: 1.64, 95% CI: 0.86-3.16, P = 0.131).

Conclusions

Fontan patients with uRV vs uLV morphology have a higher incidence of adverse cardiovascular events, including atrial arrhythmia, cardiac transplantation, and all-cause mortality.

Dominant Ventricular Morphology and Early Postoperative Course After the Fontan Procedure

Background

Single ventricle heart disease comprises a wide variety of critical heart defects that lead to the provision of systemic cardiac output by one dominant ventricle. It requires staged surgical palliation that culminates in Fontan circulation. Dominant ventricular morphology in single ventricle patients reportedly has an impact on postoperative morbidity and mortality with varying results. The objectives of this study were to examine the association between ventricular morphology and the early postoperative course after the Fontan procedure.

Methods

A retrospective cohort study in a tertiary referral pediatric medical center that included 98 consecutive patients who underwent Fontan procedure between October 2009 and May 2016. Postoperative outcomes were compared between patients with left ventricular morphology and those with right ventricular morphology (crude effect and regression analysis).

Results

Patients with right ventricular morphology had longer postoperative hospitalizations compared to patients with left ventricular morphology (26.5 days vs 18.2 days, respectively, P = .028), higher postoperative maximal vasoactive-inotropic scores (25.6 vs 12.4, P = .02), higher serum lactate levels (7.7 mmol/L vs 6.4 mmol/L, P = .03), higher proportions of ventilation throughout 24 h or more (16 patients [38%] vs 8 patients [14%], P = .009), higher proportions of ventricular dysfunction (12 patients [29%] vs 5 patients [9%], P = .0001), and lower blood oxygen saturation levels at discharge (87% vs 92%, P = .03).

Conclusions

The Fontan procedure in patients with right ventricular morphology is associated with longer postoperative hospitalization and worse early postoperative characteristics (ventricular dysfunction and atrioventricular valve regurgitation) as well as higher rates of early, transient signs of sub-optimal postoperative hemodynamics compared to those with left ventricular morphology.

Early Extubation in a Pediatric Cardiac Surgery Program Located at High Altitude

BACKGROUND

Early extubation is performed either in the operating room or in the cardiovascular intensive care unit during the first 24 postoperative hours; however, altitude might possibly affect the process. The aim of this study is the evaluation of early extubation feasibility of patients undergoing congenital heart surgery in a center located at 2,691 m (8,828 ft.) above sea level.

MATERIAL AND METHODS

Patients undergoing congenital heart surgery, from August 2012 through December 2018, were considered for early extubation. The following variables were recorded: weight, serum lactate, presence or not of Down syndrome, optimal oxygenation and acid-base status according to individual physiological condition (biventricular or univentricular), age, bypass time, and ventricular function. Standardized anesthetic management with dexmedetomidine-fentanyl-rocuronium and sevoflurane was used. If extubation in the operating room was considered, 0.08 mL/kg of 0.5% ropivacaine was injected into the parasternal intercostal spaces bilaterally before closing the sternum.

RESULTS

Four hundred seventy-eight patients were operated and 81% were early extubated. Mean pre- and postoperative SaO₂ was 92% and 98%; postoperative SaO₂ for Glenn and Fontan procedures patients was 82% and 91%, respectively. Seventy-three percent of patients who underwent Glenn procedure, 89% of those who underwent Fontan procedure (all nonfenestrated), and 85% with Down syndrome were extubated in the operating room. Reintubation rate in early extubated patients was 3.6%.

CONCLUSION

Early extubation is feasible, with low reintubation rates, at 2,691 m (8,828 ft.) above sea level, even in patients with single ventricle physiology.

Exercise Performance at Increased Altitude After Fontan Operation: Comparison to Normal Controls and Correlation with Cavopulmonary Hemodynamics

Exercise performance declines as patients who have undergone Fontan operation enter adolescence. However, the effect of altitude on functional capacity after Fontan remains inadequately studied. Our aim was to describe exercise performance in a cohort of patients with Fontan physiology living at increased altitude and compare to a normal control group and relate these data to invasively derived hemodynamics. We hypothesized that peak oxygen consumption ([Formula: see text]) would be decreased, in association with elevated mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance (PVRi). Patients were evaluated in a multidisciplinary clinic for patients with Fontan physiology. Evaluation included cardiopulmonary exercise test and cardiac catheterization at predetermined intervals. Descriptive statistics were calculated. Associations of catheterization and exercise testing measures with [Formula: see text] were estimated with Spearman correlation coefficients. One hundred patients with age- and gender-matched controls were included in the analysis. The mean age was 13.3 ± 3.9 years, with mean weight of 47.1 ± 18.4 kg. The mean [Formula: see text] was 29.0 ± 7.8 ml/kg/min, significantly lower than the control group, 40.2 ± 8.4 ml/kg/min (p < 0.0001). There was no statistically significant linear correlation between [Formula: see text] and mPAP or PVRi. We characterized exercise performance in a large cohort with Fontan physiology living at increased altitude and showed a decrease in [Formula: see text] compared to controls. Our data do not support the hypothesis that moderately increased altitude has a detrimental effect on exercise performance, nor is there a substantial link between poor cavopulmonary hemodynamics and exercise in this setting.

Systemic right ventricular morphology in the early postoperative course after extracardiac Fontan operation: is there still a need for special care?

Objectives

We aimed to compare early postoperative outcome after extracardiac (EC) Fontan operation between patients with right (RV) or left (LV) systemic ventricles.

Methods

In total, 173 consecutive patients (median age 4 years, median weight 14 kg) underwent EC Fontan between 1995 and 2013. Pre- and intraoperative data as well as detailed postoperative haemodynamic variables were compared between patients with LV [ n  = 109 (63%)] and RV [ n  = 64 (37%)].

Results

: RV patients showed significantly lower mean arterial (median 55 vs 59 mmHg, P  = 0.04), higher atrial (median 8 vs 6 mmHg, P  = 0.03) and comparable pulmonary pressure (median 14 vs 14 mmHg, P  = 0.7) as well as lower mean systemic perfusion pressure (median 39 vs 43 mmHg, P  = 0.03) on Day 0 after EC Fontan. They suffered from longer intubation time (median 18 vs 12 h, P  = 0.008), higher incidence of ascites (46% vs 28%, P  = 0.04) and need for dialysis (21% vs 4%, P  = 0.003). Prolonged inotropic support (25% vs 8%, P  = 0.02) and pharmacological treatment to reduce pulmonary vascular resistance (71% vs 53%, P  = 0.002) were more often used in RV patients and they showed more often supraventricular tachyarrhythmia (27% vs 5%, P  < 0.001) and a longer intensive care unit-stay (median 4 vs 3 days, P  = 0.03). However, early mortality, need for Fontan takedown, use of mechanical circulatory support, pleural effusions and hospital stay were not significantly different between both groups.

Conclusions

Patients with systemic RV demonstrate higher morbidity in the early postoperative course compared with patients with systemic LV anatomy and require intensified postoperative management to avoid postoperative Fontan failure.

[Comparison between patients undergoing Fontan operation with or without cardiopulmonary bypass]

Fontan operation is the final palliative stage of patients with univentricular hearts. Cardiopulmonary bypass (CPB) decreases ventricular performance and increases pulmonary artery pressures in the post operative recovery period. It seems that Fontan operation performed without CPB decreases short term morbidity and intra hospitalary length of stay.

OBJETIVE

Compare outcome in Fontan patients who have undergone surgery with or without CPB.

METHOD

This is a retrospective review of patients undergoing Fontan operation from january 2009 to december 2012. Patients were grouped according to CPB use and comparative analyses were done.

RESULTS

Ten patients were operated without CPB use. There was a discrepancy between age in both groups, being younger in the no CPB group. Around 80% of patients in both groups had a staged procedure. A 18mm graft was used in half of the cases; a fenestration was created in all cases. Length of stay was equal in both groups, there was less need of pharmacologic support and nitric oxide use in patients without CPB use. No deaths were reported also in this group. At folllow up, most patients had a class i functional status.

CONCLUSIONS

In our experience, Fontan operation without CPB has similar outcomes compared with CPB use.

Reflections on five decades of the fontan kreutzer procedure

The first successful total right heart bypass via atriopulmonary anastomosis (APA) were reported in 1971 for patients with tricuspid atresia. At the Children's Hospital of Buenos Aires, the cohort of such procedures started in July, when the first fenestrated right heart by pass was performed, with the interposition of a homograft between the right atrial appendage and the main pulmonary artery. In the second patient, instead of placing a homograft, the APA was achieved with the patient's own pulmonary root harvested from the outflow tract of the right ventricle. These techniques were soon replaced in 1978 with the development of the direct valveless posterior APA. Since the very beginning the principle was that the right atrium only functions as a pathway rather than a pump (reason why no inferior vena cava valves were ever used), and the diastolic properties of the systemic ventricle regulate the only real "pump" of this system. The late hemodynamic problems inherent of the APA diminished with modern surgical techniques like the lateral tunnel (LT) or the extracardiac conduit (EC). In spite of the improvement in prognosis and quality of life that the modern techniques have brought for univentricular hearts (UH), with the passing of time, deterioration of this system is frequently seen, due to chronic low cardiac output, elevated central venous pressure making heart transplantation the final stage of treatment. Progressive increase in pulmonary vascular resistances and ventricular dysfunction result in a decline in quality of life and survival. However, the timing of this occurrence is variable, and many survivors enjoy today a satisfactory clinical status. The challenge is to develop a better solution for UH, but in the mean time the Fontan Kreutzer palliation represents the best and only surgical option. It is undoubtedly one of the triumphs of cardiac surgery in congenital heart disease.