1. Pre-operative predictors of survival after repair of pulmonary vein stenosis.
Mauro Lo Rito MD, Tamadhir Gazzaz MD, Travis Wilder MD, Glen. S. Van Arsdell MD, Osami Honjo MD PhD, Shi-Joon Yoo MD PhD, Christopher A. Caldarone MD.
Division of Cardiovascular Surgery and Diagnostic Imaging,
Labatt Family Heart Center,
The Hospital for Sick Children Toronto, Canada

2. No disclosure

3. Develop a criteria for pulmonary vein stenosis
Objectives
Develop a criteria for pulmonary vein stenosis
Develop a predictive model for post-repair survival based on pre-operative pulmonary vein dimensions

4. Predictive models available
Based on echocardiogram
Inability to assess “upstream” pulmonary vein
Doppler gradient not always reliable
diffuse stenosis
flow redistribution
Low sensitivity
CT/MRI can assess “upstream” pulmonary vein
CT/MRI have higher sensitivity
MRI allows functional flow assessment

5. Method Retrospective study (1992-2012) using CT/MRI
Inclusion criteria:
Pulmonary vein stenosis repair with preoperative CT/MRI
Statistical analysis:
Parametric hazard analysis

6. Patient Population Study Group: 31 patients
Type of Stenosis: Primary (65%)
Secondary (35%)
Age: median 226 days (IQR days)
Body Weight: median 6.2 Kg (IQR Kg)
Follow-up: mean years (IQR: 6 months-7.6 yrs)

7. Repair and Outcomes Surgical techniques
Complete sutureless pts (58%)
Single side sutureless pts (38.7%)
PV-LA junction patch enlargement 1 pt (3.3%)

8. Pulmonary Vein Measurements
“Downstream” measurements
“Upstream” measurements
Single Vein cross-sectional area (PV-CSAi)
Total Vein cross sectional area (T-CSAi)

9. Downstream PV-CSAi < 50 mm2/m2
Criteria for Stenosis
Predicted Single PV-CSAi (mm2/m2)
Downstream PV-CSAi < 50 mm2/m2
Sensitivity = 85%
Specificity = 82%
Downstream measured single PV-CSAi (mm2/m2)

10. Morphology of Stenosis

11. Flow Redistribution
Stenotic pulmonary veins have reduced blood flow compare to non stenotic
(0.57 vs L/min/m2, p=0.0000)
Unilateral stenosis determines flow redistribution toward the contralateral pulmonary veins
Flow redistribution occurs in 65% of the patients

12. Survival
Survival:
1 year %
3 years 69+8%
5 years 64+7%
1 year

13. Factor Associated to Mortality
Early mortality (<1 year)
Upstream total cross-sectional area
(P.E.= p=0.030)
Number of stenotic pulmonary veins
(P.E.= 1.52 p=0.0069)
Late mortality (>1 year)
Downstream total cross-sectional area
(P.E.= p=0.059)

14. Early mortality - Upstream TCSAi
Upstream total cross-sectional area (mm2/m2)
90%
65%
Presentare slide in 4 punti
Introduzione
Spiegazione degli assi
Spiegazione della figura
Conclusione
(1 year survival stratified by Upstream and Downstream cross-sectional area)

15. Early mortality - Number of stenotic PV
(Median Upstream TCSAi=260 mm2/m2 – median Downstream TCSAi=160 mm2/m2)

16. Late mortality - Downstream TCSAi
Downstream total cross sectional area (mm2/m2)
Evidenziare che questo e’ un modello esemplificativo
(2 Pulmonary Veins stenosis, Median Upstream TCSAi=260 mm2/m2)

17. …in Summary
We defined an objective classification for pulmonary vein stenosis
Downstream single PV-CSAi cut-off 50 mm2/m2
Early mortality
Smaller Upstream total cross-sectional area
Greater number of stenotic pulmonary veins
Late mortality
Smaller Downstream total cross-sectional area
Dire risk factor for survival

18. Conclusion
PV with CSAi < 50 mm2/m2 are likely stenotic and with diminished flow and should be monitor closely.
CT/MRI is useful to predict survival and improve patient counselling
This methodology could identify high risk subjects that may be enrolled future in clinical trial on agents addressing pulmonary vein stenosis

19. Thank you

20. PV Cross-sectional area & flow
Cut point
P=0.000
R2=0.418
Root MSE=0.53
PV blood flow = *(PVCSAi downstream)

21. Flow and PV cross-sectional area
Stenosis cut-off
Pulmonary vein cross sectional area (mm2/m2)
Not stenotic PV
Stenotic PV
Clinically defined

22. Recurrence and Reoperation
Re stenosis
10 pts (37.5%)
Reoperation
3 pts.
No Reoperation
7 pts.
Dead
1 pt
Alive
2 pts.
Dead
4 pts.
Alive
3 pts.

23. Background Pulmonary vein stenosis: Post TAPVD repair (10-17%)
Congenital ( %)
High mortality after repair (46%-80%)
Seale A.N. et all, Heart Dec;95(23):1944-9