Department of Surgery, Dentistry, Pediatrics and Gynecology, University of Verona, Verona, Italy.
Department of Medicine and Surgery, University of Parma, Parma, Italy.
Eur J Cardiothorac Surg. 2021 Jun 14;59(6):1329-1336. doi: 10.1093/ejcts/ezab026.
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.
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.
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.
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.
法洛四联症修复术后行肺动脉瓣置换术（PVR）的适应证和时机仍存在争议。在提出的用于确定瓣膜置换时机的磁共振成像指标中，右心室（RV）舒张末期容积指数大于 160ml/m2 常用于此。最近的证据表明，该值可能仍然可以识别出 RV 功能不可逆转的患者，从而阻碍了恢复。我们的目标是使用术中视频运动学评估来定义 PVR 的时机与手术后早期功能恢复之间是否存在关系。
2016 年 11 月至 2018 年 11 月，连续 12 例患者（年龄 27.1±19.1 岁）在法洛四联症修复后平均 22.2±13.3 年接受 PVR。磁共振图像上的平均 RV 舒张末期容积为 136.9±35.7ml/m2。通过高速摄像机以 200fps 的速度在瓣膜置换前后获取视频，对术中心脏运动学进行视频运动学评估。
RV 舒张末期容积<147ml/m2 的患者明显更年轻（11.2±5.0 岁 vs 38.4±17.0 岁；P=0.005），且瓣膜置换时间间隔更短（11.0±5.2 岁 vs 30.1±11.3 岁；P=0.03）。整个队列中，能量消耗、心脏疲劳、收缩周长和术前 RV 舒张末期容积指数之间存在中度相关性。两组患者在 PVR 后所有运动学参数均减少，但舒张末期容积>147ml/m2 的患者结果不可预测。
视频运动学评估提供了法洛四联症患者行 PVR 术中 RV 恢复的深入了解。因此，术前舒张末期容积<147ml/m2 的患者可预期功能恢复。
