Very rare. Progressive stenosis of the pulmonary veins in their extrapulmonary pathway, leading, in its more serious forms, to pulmonary hypertension, and finally right heart failure.

Causes in adults : extrinsic compression (inflammatory or malignant lymphadenopathy), mediastinal mass, complication of attempts at endocavitary ablation of atrial fibrillation (radiofrequency or cryoablation around the atrial orifices of the pulmonary veins)

Causes in children (incidence: 1/100,000 to 17/106):

*        post-surgical obstruction: after the surgical treatment of total anomalous pulmonary venous return

*        anatomic obstruction: extrinsic compression or abnormal return of one of the veins in the L.A.

*        intraluminal stenosis: proliferation of fibromyxoid tissue in the  intima of the vein with gradual occlusion of its lumen, the cause of which can be:

-        primary: isolated, congenital, without associated anomalies: it could be similar to endocardial fibroelastosis

-        associated with a cardiac defect: abnormal venous return in the left atrium, often associated with a conotruncal malformation

-        acquired: associated with a septal defect or a persistent patent ductus arteriosus, with a surgical sequelae or with an endocavitary manipulation, or due to prematurity and/or a chronic lung disease: it is then a result of the increase in blood flow in the pulmonary veins, due to a left-to-right shunt, a small pulmonary vascular tree or the redistribution of the blood flow from a stenotic vein towards the others.

       In all cases, the chronic increase in pulmonary venous pressure, upstream of the stenosis causes a thickening of the muscular layer   of the large pulmonary veins and arteries, with an arteriolar remodeling such as in cases of chronic pulmonary hypertension. If more than one pulmonary segment is involved, prevailing pulmonary hypertension in that section will increase the flow and pressure in the rest of the pulmonary vascular tree causing progressively a generalized pulmonary hypertension (such as in Eisenmenger syndrome, see this term)

Associated pathologies:

-        lung prematurity with bronchodysplasia: the diagnosis is typically made around 6 months of age, despite normal previous  echocardiography; it is an important factor of mortality.

-        history of necrotising enterocolitis

-        some syndromes: Smith-Lemli-Opitz, trisomy 21 (where progression is faster).

Clinical signs: tachypnea, desaturation, and signs of right heart failure

Diagnosis:

-        chest XRay: picture of pulmonary edema with increased opacity of the interstitial space and inhomogeneously distributed ground glass opacities (according to the lobe (s) with venous congestion)

-        echocardiography, catheterization and/or cardiac MRI: see the table for the severity scores. Warning: the velocity of the flow can be reduced despite the presence of a severe stenosis if a large part of the blood flow is redistributed to the non-stenotic veins.

Treatments:

-        interventional catheterization to dilate the stenotic segment (sometimes insertion of a stent): risk of paradoxical embolism and stroke

-        surgery: a resection-anastomosis without direct suture on the atrial wall seems to be the best technique

-        lung transplantation

-        medical treatment: bevacizumab or imatinib mesylate to decrease the cellular intimal neoproliferation, losartan to increase blood levels of VE-cadherin (experimental).

Anesthetic implications:

-       very recent echocardiography: function of RV, tricuspid regurgitation, pressures in the pulmonary artery, intraventricular septum deviation (deviation to the left = suprasystemic pressure in RV), presence of a ASD or a patent oval foramen (= safety valve in case of RV failure)

-       avoid any causes of increased pulmonary vascular resistance: hypoxemia, hypercarbia, acidosis, hypothermia, vasoconstrictors agents... and use the  lowest possible insufflation pressures (low rate, I/E 1:2, PEEP according to the  patient's tolerance)

-             maintain a sufficient systemic arterial pressure (to keep a correct coronary perfusion pressure in the RV !)

-        risk of pulmonary edema in case of temporary occlusion of the less stenotic pulmonary veins

-        risk of embolic stroke, embolisms in case of endovascular dilation

References :

-        Amin R, Kwon S, Moyaedi Y, Sweezey N.

           Pulmonary vein stenosis : case report and literature review.

           Can Respi J 2009; 16: e77-80

-        Krishnan U, Feinstein JA, Adatia I, Austin ED et al.
Evaluation and management of pulmonary hypertension in children with bronchopulmonary dysplasia.
J Pediatr 2017; 188:e124-34

-        Nasr VG, Callahan R, Wichner Z, Odegard KC, DiNardo JA.
Intraluminal pulmonary vein stenosis in chidren : a 'new' lesion.
Anesth Analg 2019; 129: 27-40

Updated: July 2019