Impact of Ventricular Dysfunction and Atrioventricular Valve Regurgitation on Pre-Fontan Attrition

BACKGROUND

There is a significant incidence of pre-Fontan attrition-defined as failure to undergo Fontan completion-after superior cavopulmonary connection. This study investigated the impact of at least moderate ventricular dysfunction (VD) and atrioventricular valve regurgitation (AVVR) on pre-Fontan attrition.

METHODS

This single-center retrospective cohort study included all infants who underwent Norwood palliation from 2008 to 2020 and subsequently underwent superior cavopulmonary connection. Pre-Fontan attrition was defined as death, listing for heart transplantation before Fontan completion, or unsuitability for Fontan completion. The study's secondary outcome was transplant-free survival.

RESULTS

Pre-Fontan attrition occurred in 34 of 267 patients (12.7%). Isolated VD was not associated with attrition. However, patients with isolated AVVR had 5 times the odds of attrition (odds ratio, 5.4; 95% CI 1.8-16.2), and patients with both VD and AVVR had 20 times the odds of attrition (odds ratio, 20.1; 95% CI 7.7-52.8) compared with patients without VD or AVVR. Only patients with both VD and AVVR had significantly worse transplant-free survival compared with patients without VD or AVVR (hazard ratio, 7.7; 95% CI 2.8-21.6).

CONCLUSIONS

The additive effect of VD and AVVR is a powerful contributor to pre-Fontan attrition. Future research investigating therapies that can mitigate the degree of AVVR may help improve Fontan completion rates and long-term outcomes.

Risk factors for death or mechanical ventilation time after bidirectional cavopulmonary anastomosis in a developing country

BACKGROUND

Glenn procedure is performed for patients with cyanotic CHD and univentricular physiology and has a survival rate above 90%.

AIM

To evaluate the risk factors associated with a poor outcome after Glenn procedure.

METHODS

The data for this retrospective analysis were collected from a regional Brazilian registry of congenital heart surgeries (ASSIST initiative) from 2014 to 2019. Data from 97 patients who underwent the Glenn procedure were considered. The primary outcomes were prolonged mechanical ventilation (>24 hours post-operatively) or in-hospital death, alone and combined.

RESULTS

The overall in-hospital mortality was 13.4% (n = 13). Prolonged mechanical ventilation occurred in 52% (n = 51) of the patients. Our analysis found that risk factors for death or prolonged post-operative mechanical ventilation were cardiopulmonary bypass duration and post-operative lactate, whereas weight-for-age z-score and age at surgery were risk factors for prolonged mechanical ventilation. Cardiopulmonary bypass duration increased (adjusted odds ratio: 1.02; 95 % CI: 1.01, 1.03) and age at surgery decreased (adjusted odds ratio: 0.96; 95 % CI: 0.93, 0.99) the odds of the combined outcome.

CONCLUSIONS

Age at surgery, post-operative lactate, and low-weight-for-age z-score are associated with prolonged mechanical ventilation and death following the Glenn procedure.

Risk Factors for Thrombus Formation at Stage 2 Palliation and Its Effect on Long-Term Outcome in Patients With Univentricular Heart

Thrombus formation is a feared complication following bidirectional cavopulmonary shunt (BCPS). We aimed to investigate the effect of thrombus formation on outcome. BCPS was performed in 525 patients at our center between 1998 and 2018. The impacts of thrombus formation on survival and probability of Fontan completion were analyzed, and risk factors for thrombus formation were examined. Thrombus formation occurred in 30 patients (5.7%). Compared with the remaining 495 patients, there was no significant difference in the median age at BCPS (4.9 vs 4.7 months; P = 0.587). However, unbalanced atrioventricular septal defects (17 vs 5%; P = 0.008) and preoperative ventricular dysfunction (23.3 vs 8%; P = 0.004) were more frequent in patients who developed a thrombus. Thrombolytic therapy was performed in all patients and surgical thrombus removal was required in 13 patients. In-hospital mortality was higher in patients with thrombus (30.0 vs 2.2%; P < 0.001). Of 505 hospital survivors, an estimated survival at 1 year after hospital discharge following BCPS was 84.4% (95% CI, 76.1-92.7%) in patients with thrombus and 96.8% (95% CI, 96.0-97.6%) in those without (P < 0.001). Cumulative incidence of Fontan completion at 3 years after BCPS was 52.8% (95% CI, 30.3-75.2%) in patients with thrombus and 90.1% (95% CI, 87.2-92.9%) in those without (P = 0.004). Higher left atrial pressure (OR = 1.165; P = 0.029) and longer cardiopulmonary bypass time (OR = 1.013, P = 0.001) at BCPS were independent risk factors for thrombus formation after BCPS. Thrombus formation after BCPS poses a significant risk for survival and Fontan completion. Preoperative higher left atrial pressure and longer cardiopulmonary bypass time are significant risk factors.

Hypoplastic left heart syndrome: current modalities of treatment and outcomes

Hypoplastic left heart syndrome is a constellation of malformations which result from the severe underdevelopment of any left-sided cardiac structures. Once considered to be universally fatal, the prognosis for this condition has tremendously improved over the past four decades since the work of William Norwood in the early 1980s. Today, a staged surgical approach is applied for palliating this distinctive cohort of patients, in which they undergo three operative procedures in the first 10 years of their life. Advancements in medical technologies, surgical techniques, and our growing experience in the management of HLHS have made survival into adulthood a possibility. Through this review, we present the different phases of the staged approach with primary focus on stage 1-its modifications, current technique, alternatives, and latest outcomes.

Superior vena cava obstruction after the Glenn procedure

Acute obstruction of superior vena cava anastomosis right after the Glenn procedure may lead to tragic consequences. We describe the case of a one-year-old child with tricuspid atresia and a previous Blalock-Taussig shunt procedure, who presented severe low cardiac output syndrome right after the Glenn procedure and died forty-four hours after the procedure. The autopsy showed obstruction of the superior vena cava anastomosis. Patients that present superior vena cava syndrome and low cardiac output right after the Glenn procedure should have the surgical anastomosis revised immediately.

Mechanical Circulatory Support for Single Ventricle Failure

Mechanical circulatory support (MCS) for failing single ventricle (SV) physiology is a complex and challenging problem, which has not yet been satisfactorily addressed. Advancements in surgical strategies and techniques along with intensive care management have substantially improved the outcomes of neonatal palliation for SV physiology, particularly for hypoplastic left heart syndrome (HLHS). This is associated with a steady increase in the number of SV patients who are susceptible to develop heart failure (HF) and would potentially require MCS at a certain stage in their palliation. We have reviewed the literature regarding the reported modalities of MCS use in the management of SV patients. This includes analysis of various devices and strategies used for failing circulation at distinct stages of the SV pathway: after neonatal palliation, after the superior cavo-pulmonary connection (SCPC), and after total cavo-pulmonary connection (TCPC).