Congenital Heart Disease

1350499 - Ventricular-ventricular interactions vary after staged left ventricular recruitment for left heart hypoplasia.

Wednesday, January 25, 2023

Location: E-POSTER

Presenting Author(s)

Mehul D. Patel, MD

Assistant Professor
The University of Texas Health Science Center at Houston
Houston, Texas, United States

Primary Author(s)

Mehul D. Patel, MD

Assistant Professor
The University of Texas Health Science Center at Houston
Houston, Texas, United States

Co-Author(s)

SU

Santosh C. Uppu, MD

Associate Professor
The University of Texas Health Science Center at Houston, Texas, United States
BP

Blaz Podgorsek, MD

Resident Physician
The University of Texas Health Science Center at Houston, United States
JD

Julija Dobrila, MD

Resident Physician
The University of Texas Health Science Center at Houston, United States
RN

Ronak Naik, MD

Associate Professor
University of Tennessee Health Science Center
Memphis, Tennessee, United States
CG

Christopher Greenleaf, MD, MBA

Assistant Professor
The University of Texas Health Science Center at Houston, Texas, United States

Background: Staged left ventricular recruitment (LVR) is a growing management strategy for patients with left ventricular (LV) hypoplasia, and involves multiple staged surgical interventions including supplementation of pulmonary blood flow and atrial septal defect restriction. This may result in increased LV size, however changes in systolic function of both the systemic right ventricle (RV) and LV have not been previously described.

Methods: LV hypoplasia patients with cardiac magnetic resonance (CMR) who underwent LVR at our center from 2017-2021 were retrospectively reviewed. Exclusion criteria included inadequate CMR data from either pre- or post-LVR. Medical history and clinical characteristics were compared. Volumetry was measured and verified by 2 experienced readers. RV and LV peak longitudinal (LS), circumferential (CS), and radial strain (RS) were measured using tissue tracking software (cvi42, Circle Cardiovascular Imaging, Calgary, Canada).

Results:

Three patients met inclusion criteria, with median age 46.1 months (range 6.2-48.5) at pre-LVR CMR and median follow up period of 11.8 months (range 9.1-13.2) at post-LVR CMR. All patients had LV hypoplasia and underwent a Norwood operation followed by bidirectional Glenn procedure. LVR included ASD restriction to a 4-6 mm defect and 6-8mm RV-pulmonary artery conduit placement. One patient underwent mitral valve repair and subaortic resection, with postoperative complete heart block requiring dual chamber pacemaker. LV size and output increased in all patients post-LVR: increase in LV end diastolic volume ranged 14-37.6 ml/m2, decrease in LV diastolic eccentricity index ranged 0.24-0.34, increase in LV to RV stroke volume ratio ranged 0.2-0.27. Multiple markers of LV systolic function also increased in all patients (Figure). RV systolic function (including RVLS and RVCS) increased in 2 patients post-LVR, but decreased in 1 patient who required permanent ventricular pacing. This same patient also had decreases in LVCS and LVRS post-LVR. One patient underwent successful biventricular conversion; 2 await favorable hemodynamics for biventricular conversion. All patients were subsequently discharged home.

Conclusion:

We demonstrated improvement in LV size, output and markers of LV and RV systolic function in select patients post-LVR, suggesting positive ventricular-ventricular interactions with LV volume loading. However, LV and RV systolic function may be negatively affected by multiple interventions and pacing in some cases. Further study is warranted to carefully track changes both in ventricular size and systolic function for this unique management strategy. CMR is a versatile tool to quantify multiple measures of ventricular systolic function.