Relationship of Aortopulmonary Collaterals and Pulmonary Artery Development During Staged Single Ventricle Reconstruction

To evaluate the relationship of aortopulmonary collaterals and the development of central pulmonary arteries during staged palliation. A total of 287 patients, who underwent staged palliation with bidirectional cavopulmonary shunt and total cavopulmonary connection between 2008 and 2019, had available angiography. Pulmonary artery index was calculated using pulmonary angiography as described by Nakata and colleagues. Aortopulmonary collaterals were observed in 47 (16%) patients at stage II palliation, in 131 (46%) at total cavopulmonary connection, and afterwards in 49 (7%). The interventional closure of aortopulmonary collaterals was performed before stage II in 12 (4%) patients, before Fontan completion in 38 (13%), and afterwards in 39 (14%). Presence of aortopulmonary collaterals before stage II was not associated with the pulmonary artery index (129 vs. 150 mm2/m2, p = 0.176) at stage II. In contrast, aortopulmonary collaterals before the Fontan completion were associated with lower pulmonary artery index (154 vs. 172 mm2/m2, p = 0.005), and right pulmonary artery index (99 vs. 106 mm2/m2, p = 0.006). Patients who underwent interventional closure of aortopulmonary collaterals before total cavopulmonary connection had lower pulmonary artery index (141 vs. 169 mm2/m2, p < 0.001), lower right pulmonary artery index (93 vs. 106 mm2/m2, p = 0.007), and left pulmonary artery index (54 vs. 60 mm2/m2, p = 0.013) at Fontan completion. The presence of aortopulmonary collaterals did not influence pulmonary artery size by the time of stage II. However, presence of aortopulmonary collaterals was associated with under-developed pulmonary arteries at Fontan completion, especially in patients who needed interventional closure of aortopulmonary collaterals.

Tachyarrhythmia after the total cavopulmonary connection: incidence, prognosis, and risk factors

OBJECTIVE

The purpose of this study is to evaluate the incidence and outcomes regarding tachyarrhythmia in patients after total cavopulmonary connection.

METHODS

A retrospective analysis of 620 patients who underwent total cavopulmonary connection between 1994 and 2021 at our institution was performed. Incidence of tachyarrhythmia was depicted, and results after onset of tachyarrhythmia were evaluated. Factors associated with the onset of tachyarrhythmia were identified.

RESULTS

A total of 52 (8%) patients presented with tachyarrhythmia that required medical therapy. Onset during hospital stay was observed in 27 patients, and onset after hospital discharge was observed in 32 patients. Freedom from late tachyarrhythmia following total cavopulmonary connection at 5, 10, and 15 years was 97, 95, and 91%, respectively. The most prevalent late tachyarrhythmia was atrial flutter (50%), followed by supraventricular tachycardia (25%) and ventricular tachycardia (25%). Direct current cardioversion was required in 12 patients, and 7 patients underwent electrophysiological study. Freedom from Fontan circulatory failure after onset of tachyarrhythmia at 10 and 15 years was 78% and 49%, respectively. Freedom from occurrence of decreased ventricular systolic function after the onset of tachyarrhythmia at 5 years was 85%. Independent factors associated with late tachyarrhythmia were dominant right ventricle (hazard ratio, 2.52, p = 0.02) and weight at total cavopulmonary connection (hazard ratio, 1.03 per kilogram; p = 0.04). Type of total cavopulmonary connection at total cavopulmonary connection was not identified as risk.

CONCLUSIONS

In our large cohort of 620 patients following total cavopulmonary connection, the incidence of late tachyarrhythmia was low. Patients with dominant right ventricle and late total cavopulmonary connection were at increased risk for late tachyarrhythmia following total cavopulmonary connection.

Impact of calorie intake and weight gain after Norwood procedure on the outcome of stage II palliation

BACKGROUND

This study aimed to assess the impact of caloric intake and weight-for-age-Z-score after the Norwood procedure on the outcome of bidirectional cavopulmonary shunt.

METHODS

A total of 153 neonates who underwent the Norwood procedure between 2012 and 2020 were surveyed. Postoperative daily caloric intake and weight-for-age-Z-score up to five months were calculated, and their impact on outcome after bidirectional cavopulmonary shunt was analysed.

RESULTS

Median age and weight at the Norwood procedure were 9 days and 3.2 kg, respectively. Modified Blalock-Taussig shunt was used in 95 patients and right ventricle to pulmonary artery conduit in 58. Postoperatively, total caloric intake gradually increased, whereas weight-for-age-Z-score constantly decreased. Early and inter-stage mortality before stage II correlated with low caloric intake. Older age (p = 0.023) at Norwood, lower weight (p < 0.001) at Norwood, and longer intubation (p = 0.004) were correlated with low weight-for-age-Z-score (< -3.0) at 2 months of age. Patients with weight-for-age-Z-score < -3.0 at 2 months of age had lower survival after stage II compared to those with weight-for-age-Z-score of -3.0 or more (85.3 versus 92.9% at 3 years after stage II, p = 0.017). There was no difference between inter-stage weight gain and survival after bidirectional cavopulmonary shunt between the shunt types.

CONCLUSION

Weight-for-age-Z-score decreased continuously throughout the first 5 months after the Norwood procedure. Age and weight at Norwood and intubation time were associated with weight gain. Inter-stage low weight gain (Z-score < -3) was a risk for survival after stage II.

Longitudinal analysis of systemic ventricular function and atrioventricular valve function after the Norwood procedure

OBJECTIVES

To evaluate longitudinal systemic ventricular function and atrioventricular valve regurgitation in patients after the neonatal Norwood procedure.

METHODS

Serial postoperative echocardiographic images before Fontan completion were assessed in neonates who underwent the Norwood procedure between 2001 and 2020. Ventricular function and atrioventricular valve regurgitation were compared between patients with modified Blalock-Taussig shunt and right ventricle to pulmonary artery conduit.

RESULTS

A total of 335 patients were identified including 273 hypoplastic left heart syndrome and 62 of its variants. Median age at Norwood was 8 (7-12) days. Modified Blalock-Taussig shunt was performed in 171 patients and the right ventricle to pulmonary artery conduit in 164 patients. Longitudinal ventricular function and atrioventricular valve regurgitation were evaluated using a total of 4352 echocardiograms. After the Norwood procedure, ventricular function was initially worse (1-30 days) but thereafter better (30 days to stage II) in the right ventricle to pulmonary artery conduit group (P < 0.001). After stage II, the ventricular function was inferior in the right ventricle to the pulmonary artery conduit group (P < 0.001). Atrioventricular valve regurgitation between the Norwood procedure and stage II was more frequent in the modified Blalock-Taussig shunt group (P < 0.001). After stage II, there was no significant difference in atrioventricular valve regurgitation between the groups (P = 0.171).

CONCLUSIONS

The effect of shunt type on haemodynamics after the Norwood procedure seems to vary according to the stage of palliation. After the Norwood, the modified Blalock-Taussig shunt is associated with poorer ventricular function and worse atrioventricular valve regurgitation compared to right ventricle to pulmonary artery conduit. Whereas, after stage II, modified Blalock-Taussig shunt is associated with better ventricular function and comparable atrioventricular valve regurgitation, compared to the right ventricle to pulmonary artery conduit.

Comparison of ductus stent versus surgical systemic-to-pulmonary shunt as initial palliation in patients with univentricular heart

OBJECTIVES

In this study, we aimed to compare infants with univentricular hearts who underwent an initial ductus stenting to those receiving a surgical systemic-to-pulmonary shunt (SPS).

METHODS

All infants with univentricular heart and ductal-dependent pulmonary blood flow who underwent initial palliation with either a ductus stenting or a surgical SPS between 2009 and 2022 were reviewed. Outcomes were compared after ductus stenting or SPS including survival, probability of re-interventions and the probability to reach stage II palliations.

RESULTS

A total of 130 patients were evaluated, including 49 ductus stenting and 81 SPSs. The most frequent primary diagnosis was tricuspid atresia in 27, followed by pulmonary atresia with intact ventricular septum in 19 patients. There was comparable hospital mortality (2.0% stent vs 3.7% surgery, P = 0.91) between the groups, but shorter intensive care unit stay (median 1 vs 7 days, P < 0.01) and shorter hospital stay (median 7 vs 17 days, P < 0.01) were observed in patients with initial ductus stenting, compared to those with SPS. However, acute procedure-related complications were more frequently observed in patients with ductus stenting, compared with those with SPS (20.4 vs 6.2%, P = 0.01), and 10 patients needed a shunt procedure after the initial ductus stent. The cumulative incidence of reaching stage II was similar between ductus stenting and SPS (88.0 vs 90.6% at 12 months, P = 0.735). Pulmonary artery (PA) index (median 194 vs 219 mm2/m2, P = 0.93) at stage II was similar between patients with ductus stenting and SPS. However, the ratio of the left to the right PA index [0.69 (0.45-0.95) vs 0.86 (0.51-0.84), P = 0.015] was higher in patients who reached stage II with surgical shunt physiology, compared with patients with ductus stent physiology.

CONCLUSIONS

After initial ductus stenting in infants with univentricular heart, survival is comparable and post-procedural recovery shorter, but more acute stent dysfunctions and lower development of left PA are observed, compared to acute shunt dysfunctions. The less invasive procedure and shorter hospital stay are at the expense of more stent reinterventions.

Impact of early postoperative haemodynamic and laboratory parameters on outcome after the Fontan procedure

OBJECTIVE

To identify early postoperative haemodynamic and laboratory parameters predicting outcomes following total cavopulmonary connection.

METHODS

Patients who underwent total cavopulmonary connection between 2012 and 2021 were evaluated. Serial values of mean pulmonary artery pressure, mean arterial pressure, peripheral oxygen saturation, and lactate levels were collected. The influence of these variables on morbidities was analyzed. Cut-off values were calculated using the receiver operating characteristic analysis.

RESULTS

A total of 249 patients were included. All patients had previous bidirectional cavopulmonary shunt. Median age and weight at total cavopulmonary connection were 2.2 (1.8-2.7) years and 11.7 (10.7-13.4) kg, respectively. All patients were extubated in the ICU at a median of 3 (2-5) hours after ICU admission. Postoperative pulmonary artery pressure, around 12 hours after extubation, was significantly associated with chest tube drainage (p = 0.048), chylothorax (p = 0.021), ascites (p = 0.016), and adverse events (p = 0.028). Receiver operating characteristic analysis revealed a cut-off value of 13-15 mmHg for chest tube drainage and chylothorax and 17 mmHg for ascites and adverse events. Mean arterial pressure 1 hour after extubation was associated with prolonged chest tube drainage (p = 0.015) and adverse events (p = 0.008). Peripheral oxygen saturation 6 hours after extubation (p = 0.003) was associated with chest tube duration and peripheral oxygen saturation 1 hour after extubation (p < 0.001) was associated with ascites. Lactate levels on 2nd postoperative day (p = 0.022) were associated with ascites and lactate levels on 1st postoperative day (p = 0.009) were associated with adverse events.

CONCLUSIONS

Higher pulmonary artery pressure, lower mean arterial pressure, lower peripheral oxygen saturation, and higher lactate in early postoperative period, around 12 hours after extubation, predicted in-hospital and post-discharge adverse events following total cavopulmonary connection.

Impact of aortopulmonary collaterals on adverse events after total cavopulmonary connection

OBJECTIVES

Effects of aortopulmonary collaterals (APCs) on outcomes after the total cavopulmonary connection (TCPC) are unclear. This study evaluated the incidence of APCs before and after TCPC and analysed the impacts of APCs on adverse outcomes.

METHODS

A total of 585 patients, who underwent TCPC from 1994 to 2020 and whose preoperative angiographies were available, were included. Pre-TCPC angiograms in all patients were used for the detection of APCs, and post-TCPC angiograms were evaluated in selected patients. Late adverse events included late death, protein-losing enteropathy (PLE) and plastic bronchitis (PB).

RESULTS

The median age at TCPC was 2.3 (1.8-3.4) years with a body weight of 12 (11-14) kg. APCs were found in 210 patients (36%) before TCPC and in 81 (14%) after TCPC. The closure of APCs was performed in 59 patients (10%) before TCPC, in 25 (4.2%) at TCPC and in 59 (10%) after TCPC. The occurrences of APCs before and after TCPC were not associated with short-term or mid-term mortality. The APCs before TCPC were associated with chylothorax (P = 0.025), prolonged chest tube duration (P = 0.021) and PB (P = 0.008). The APCs after TCPC were associated with PLE (P < 0.001) and PB (P < 0.001). With APCs following TCPC, freedom from PLE and PB was lower than without (P < 0.001, P < 0.001).

CONCLUSIONS

APCs before TCPC were associated with chylothorax, prolonged chest tube duration and PB. APCs after TCPC were associated with both PLE and PB. The presence of APCs might affect the lymph drainage system and increase the incidence of chylothorax, PLE and PB.