Cardiac Catheterization During Extracorporeal Membrane Oxygenation After Congenital Cardiac Surgery: A Multi-Center Retrospective Study

OPTILOW: A Low-Profile Approach for Implanting Optimus-L Stents in Infants and Children

BACKGROUND

Stent implantation poses challenges in small children due to their limited vessel size and rapid growth. This multicenter study evaluates in vivo efficacy of implanting Optimus-L stents in small patients using a low-profile approach.

METHODS

We retrospectively reviewed data from children weighing ≤20 kg with congenital heart stenotic lesions who received Optimus-L stents manually mounted on small-sized balloon catheters (diameter ≤12 mm) using a hand-actuated compression tool and implanted through small-sized sheaths (≤8 Fr) at our institutions between May 2022 and January 2024. Stent performance was assessed.

RESULTS

We identified 28 patients (67.8% male) with median age and weight of 3.4 years (interquartile range [IQR], 1.5-5.5) and 12.9 kg (IQR, 9.1-16.4). Six (21.4%) were infants, 11 (39.3%) ≤10 kg. Stenotic lesions included 16 branch pulmonary arteries, 9 aortic isthmus, 2 right ventricular outflow tracts, and 1 Glenn anastomosis. Percentage of stenosis was 50% (IQR, 36%-58%). All implantations were successful without complications. The procedures mostly used 7 Fr sheaths for stents on 6, 7, and 8 mm balloons and 8 Fr sheaths for 9, 10, 12 mm balloons. Median stent expansion percentage was 95% (IQR, 90%-96%). Median vessel diameters increased from 4.6 mm (IQR, 3.8-5.1) to 8.8 mm (IQR, 7.5-9.5) (P<0.001), with median stenosis expansion at 103% (IQR, 51%-146%). Median stent shortening was 1.9% (IQR, 0%-3.9%). Two patients required redo stent balloon dilation after 18 and 20 months. Median follow-up was 8 months (IQR, 3.2-13.2). Median last recorded Doppler velocity on implanted stents was 1.6 m/s (IQR, 1.2-2).

CONCLUSIONS

Optimus-L stents can safely treat arterial and venous stenosis in infants and small children via a low-profile approach with good outcomes.

Cardiac Catheterization and Interventions in Pediatric Patients on ECMO: Analysis of the IMPACT Registry

Background

There are limited published studies on the performance and safety of cardiac catheterization in pediatric patients on extracorporeal membrane oxygenation (ECMO). We sought to understand the utilization and procedural safety of cardiac catheterization in pediatric patients on ECMO. We also aimed to understand differences in the types of interventions and outcomes in patients with single ventricle (SV) physiology compared to those with biventricular physiology.

Methods

Characteristics and outcomes for patients undergoing cardiac catheterization while on ECMO were collected from the American College of Cardiology National Cardiovascular Data Registry: IMPACT (Improving Pediatric and Adult Congenital Treatment) Registry from 2011-2022.

Results

There were 3473 cardiac catheterizations performed on 2980 pediatric patients during the study period. Patients with SV comprised 31.6% of the population. Survival to hospital discharge was 53.2% overall, 45.2% in patients with SV, and 56.8% in patients with 2 ventricles. Interventional procedures occurred in 52.5% of cases. Major adverse events occurred in 11.5%, with arrhythmia, bleeding events, and unplanned cardiac/other surgeries being the commonest. Regression analysis found SV was significantly associated with major adverse events, as were interventional procedures, female sex, non-Hispanic race, diabetes mellitus, procedure status classified as salvage vs elective, and systemic heparinization.

Conclusions

This is the first large, multicenter review of safety and outcomes in pediatric patients undergoing cardiac catheterization while on ECMO. The study identifies common adverse events during the procedure as well as risk factors associated with the same. The presented data can serve for benchmarking, quality assessment as well as potential future research.

Safety, timing, and outcomes of early post-operative cardiac catheterisation following congenital heart surgery

OBJECTIVE

The safety of early post-operative cardiac catheterisation has been described following congenital heart surgery. Optimal timing of early post-operative cardiac catheterisation remains uncertain. The aim of this study was to describe the safety of early post-operative cardiac catheterisation and its impact on cardiac ICU and hospital length of stay, duration of mechanical ventilation, and extracorporeal support.

METHODS

This single-centre retrospective cohort study compared clinical and outcome variables between "early" early post-operative cardiac catheterisation (less than 72 hours after surgery) and "late" early post-operative cardiac catheterisation (greater than 72 hours after surgery) groups using Chi-squared, Student's t, and log-rank test (or appropriate nonparametric test).

RESULTS

In total, 132 patients were included, 22 (16.7%) "early" early post-operative cardiac catheterisation, and 110 (83.3%) "late" early post-operative cardiac catheterisation. Interventions were performed in 63 patients (51.5%), 7 (11.1%) early and 56 (88.9%) late. Complications of catheterisation occurred in seven (5.3%) patients, two early and five late. There were no major complications. Patients in the late group trended towards a longer stay in the cardiac ICU (19 days [7, 62] versus 11.5 days [7.2, 31.5], p = 0.6) and in the hospital (26 days [9.2, 68] versus 19 days [13.2, 41.8], p = 0.8) compared to the earlier group.

CONCLUSION

"Early" early post-operative cardiac catheterisation was associated with an overall low rate of complications. Earlier catheterisations trended towards shorter cardiac ICU and hospital length of stays. Earlier catheterisations may lead to earlier recovery for patients not following an expected post-operative course.

Proof of Concept: A New Solution for Low-Profile Transcatheter Implantation of Optimus-L Stents in Small Children

BACKGROUND

There is no stent designed or approved for use in infants. We sought to obtain in vitro and in vivo data on a new concept conceived to implant Optimus-L stents at infant vessel diameters and offer a potential long term stent solution.

METHODS

Nineteen Optimus-L stents were mounted on 8 types of angioplasty balloons with diameters 6, 8, and 10 mm with the use of an injection-moulded hand crimper. We evaluated balloon-stent unit (BSU) stability before insertion and advancement through short Terumo introducers with incremental French size and possibility of side-arm contrast injections. Three types of long sheaths were tested. Stents were inflated to balloon nominal diameters and re-expanded to 18 and 23 mm. Stent recoil, foreshortening, and fracture were evaluated. In vivo implantations were performed afterward.

RESULTS

In vitro: Medtronic Evercross balloons and modified Terumo Destination sheaths were the best combination: BSUs were inserted in 6 F sheaths with possible injections (for 6 and 8 mm balloons), and 7 F sheaths without injections (for the 10 mm balloon). Retrieving BSUs inside the sheath required 1 additional F-size. Boston Scientific Sterling and Balton Lovix balloons, as well as APT Braidin L guiding sheaths showed unsatisfactory performance. Dilation up to 23 mm was possible, and stent shortening was < 24% at 18 mm and < 37% at 23 mm. Recoil was limited, and no stent fractured. In vivo: Optimus-L stents were used to treat 2 infants with aortic coarctation and 2 children with pulmonary artery stenosis with the use of 8 mm balloons and low-profile access.

CONCLUSIONS

Optimus-L stents can be implanted safely in small patients with a low-profile approach. These stents have the potential to achieve adult size while maintaining structural integrity.