Page 15 - Journal of Structural Heart Disease Volume 4, Issue 1

Original Scienti c Article
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cases, with mean RV end-diastolic volumes (RVEDVi) of 155 ml/m2 on CMR. Mean minimum “annular” diam- eter on TTE was 22.8 mm and mean RVOT diameter was 31.8 mm. The valve was successfully implanted in all patients, with implanted valve diameters ranging from 26 to 32 mm. The mean fluoroscopy time (FT) was 22.8 min. Upon mean follow-up of 3.4 months, PR grade was 0 (n = 3) or 1 (n = 2) in all cases. NYHA class improved at least one class in all cases, and RV vol- umes assessed by TTE normalized in all three patients with follow-up to 3 months. This rst cohort of pa- tients is still being followed up and shows continued good valve function up to 3 years post-procedure.
Promphan et al. reported one of the earliest clini- cal human experiences using the Venus P-valve [23]. In this study, six patients (four males) with a median age of 18.5 years and mean body weight of 53.8 kg were selected. All patients were NYHA class II and had severe PR with mean RVEDVi of 146 ml/m2 on CMR. The valve was successfully implanted in all patients, with implanted valve diameters ranging from 24 to 32 mm. The mean FT was 29.8 min. No patients had significant RVOT gradient or PR immediately after valve implantation. Only one patient had unexpected mild proximal valve migration to the RV body during withdrawal of the delivery system, causing mild para- valvar leak and significant tricuspid regurgitation. At 6-month follow-up, the median RVEDVi decreased from 146 to 108 ml/m2. Additionally, the Doppler sys- tolic peak gradient across the valve ranged from 4 to 40 mmHg, there was no evidence of stent fracture on fluoroscopy or structural valve failure, and patients’ symptoms improved signi cantly.
Recently, Husain and colleagues reported their experience implanting the Venus P-valve in Europe [24]. In this study, ve patients with a median age of 14 years and mean body weight of 88.4 kg were selected. Two patients were NYHA class II, and three patients were class I. All patients had signi cant PR with a mean RVEDVi of 131 ml/m2 on CMR. The valve was successfully implanted in all patients, with im- planted valve diameters ranging from 28 to 32 mm. The mean procedure duration was 136.2 min. No patients had significant RVOT gradient or PR imme- diately after valve implantation. There was no mor- tality and no major morbidity. Only one patient had jailing of the right PA requiring right PA stent implan-
tation. Post-procedural follow-up (median follow-up 8.5 months, range 3–15 months) with TTE and CMR showed no restenosis or regurgitation with signi - cant improvement in RVEDVi.
In 2017, Garay et al. reported successful implanta- tion of the Venus P-valve in 10 patients (seven female) [25]. The patients’ mean age was 32 years and mean weight was 59.6 kg. Seven patients were NYHA class II, and three patients were class III. All patients had mod- erate to severe PR with mean RVEDVi of 139 ml/m2 on CMR. The valve was successfully implanted in all pa- tients, with implanted valve diameters ranging from 26 to 32 mm. The mean FT was 29 min. There were no procedure-related complications and no evidence of paravalvular leak in any of the patients. During a mean follow-up of 12 months (range 4–21 months), all patients remained NYHA class I. TTE and CMR 6 months after implantation of the valve showed sus- tained and significant reduction of PR in all patients. In six patients, the median pulmonary regurgitant fraction was 1% (range 0–5%) and the RVEDVi was 78 ml/m2 (range 66–100 ml/m2). No stent fracture was demonstrated on fluoroscopic follow-up at 6 months.
Current Status of the Valve
As of August 2017, the Venus P-valve has been im- planted in 110 patients with very good initial results worldwide (China, United Kingdom, India, Thailand, Ireland, Indonesia, Chile, Jordan, Qatar, and Argenti- na). All patients are undergoing rigorous follow-up protocols, and obtained data will be published in the future. The manufacturer has submitted a protocol to the noti ed bodies in a few European countries to evaluate the valve in patients after transannular patch repair with severe PR. Data obtained will be used to seek a CE mark approval.
Summary
It is challenging to deal with patients who have un- dergone tetralogy of Fallot repair using the transan- nular patch repair technique and who have a larger dilated RVOT that exceeds the size of commercially available balloon expandable valves. Several tech- niques have been described to adapt these valves for patients with native RVOT; although they show good
Journal of Structural Heart Disease, February 2018
Volume 4, Issue 1:1-8