Right ventricular functional recovery depends on timing of pulmonary valve replacement in tetralogy of Fallot: a video kinematic study

Abstract

OBJECTIVES Indications for and timing of pulmonary valve replacement (PVR) after tetralogy of Fallot repair are controversial. Among magnetic resonance imaging indices proposed to time valve replacement, a right ventricular (RV) end-diastolic volume index greater than 160 ml/m2 is often used. Recent evidence suggests that this value may still identify patients with irreversible RV dysfunction, thus hindering recovery. Our goal was to define, using intraoperative video kinematic evaluation, whether a relationship exists between timing of PVR and early functional recovery after surgery. METHODS Between November 2016 and November 2018, a total of 12 consecutive patients aged 27.1 ± 19.1 years underwent PVR on average 22.2 ± 13.3 years after tetralogy of Fallot repair. Mean RV end-diastolic volume evident on the magnetic resonance images was 136.9 ± 35.7 ml/m2. Intraoperative cardiac kinematics were assessed by video kinematic evaluation via a high-speed camera acquiring videos at 200 fps before and after valve replacement. RESULTS Patients presenting with RV end-diastolic volume <147 ml/m2 were significantly younger (11.2 ± 5.0 vs 38.4 ± 17.0; P = 0.005) and had a shorter time interval to valve replacement (11.0 ± 5.2 vs 30.1 ± 11.3; P = 0.03). The entire population showed a moderate correlation among energy expenditure, cardiac fatigue, perimeter of contraction and preoperative RV end-diastolic volume index. Both groups showed a reduction in all kinematic parameters after PVR, but those with end-diastolic volume >147 ml/m2 showed an unpredictable outcome. CONCLUSIONS Video kinematic evaluation provides insight into intraoperative RV recovery in patients with tetralogy of Fallot undergoing PVR. Accordingly, functional recovery can be expected in patients with preoperative end-diastolic volume <147 ml/m2.

Artificial Intelligence Supports Decision Making during Open-Chest Surgery of Rare Congenital Heart Defects

“…First, we assessed the cardiac kinematics (Figure 6a) in one ToF patient who underwent PVR with a known favorable outcome (discharged after 7 days of hospitalization). As in our previous works [22,23], we observed a decreasing trend for all Vi.Ki.E. parameters, which was significant for the energy and perimeter.…”

“…The Vi.Ki.E. assessment showed a decreasing trend for all kinematic parameters in line with our previous studies on right ventricular unloading [22,23]. We used the signal-to-noise ratio (SNR) predictor as a representative feature to build a simplified 2D classification model, named "decision surface", for both coordinates.…”

“…We applied Vi.Ki.E. in the field of myocardial ischemia [21] and complex congenital heart diseases such as Tetralogy of Fallot (ToF) [22,23], which is the most common RV pathology representing 7-10% of the congenital cardiac defects [24]. Interestingly, in our most recent work on ToF [23], we observed a promising correlation between the before surgery Vi.Ki.E.…”

“…In this study, we trained two SML classifiers based on Vi.Ki.E., a contactless imaging technology developed by our laboratories to evaluate the RV kinematics [21][22][23]43]. We used the Vi.Ki.E.…”

Video analysis of ex vivo beating hearts during preservation on the TransMedics® organ care system

“…The coordinates are then analyzed using the Vi.Ki.E. system, which is written in MATLAB programming language (MathWorks, Inc., Natick, MA, United States) and returns the kinematic parameters such as contractility (maximal contraction velocity), cardiac force, energy expenditure, and trajectory perimeter (tissue compliance), as previously described by Rozzi et al ( 10 ).…”