An unknown cause of aortic valve stenosis: polycythemia vera

Abstract

Polycythemia vera (PV) is a chronic myeloproliferative disorder characterized by an abnormal increase in red blood cells. The involvement of the heart during the course of the illness represents a common cause of morbidity and it is linked to an increased thrombogenic risk subsequent to higher blood viscosity. In our study we evaluated by echocardiography a PV patient population. Our study enrolled 44 patients affected by PV. 17 of them were women and 27 were men. Mean patient age was 66.7. The average follow-up period was 5 years and the average duration of the illness was 5.7 years, since the time of diagnosis. All patients were evaluated quarterly by a cardiovascular objective examination and an ultrasound of the heart, with regard to platelet count and hematocrit (Ht) variations during the follow-up period, according to the therapy administered. Patients were treated with hydrossiurea and pipobroman and they underwent an eritrocitoapheresis in emergency conditions in which Ht levels rose too much, in spite of the myelosuppressive therapy. The echocardiographic assessment of the heart structure and function by the B mode technique revealed the presence of a sclerocalcific degeneration of the aortic valve in 58 % of patients, involving the aortic root more then the valve. An average trans-aortic flow velocity of 1.92 m/s was detected by Doppler technique; a stenosis was demonstrated in 11 patients (25.5 % of the entire population). After diagnosing the presence of a stenosis, we researched a possible cause of it. PV is a systemic disease well-known causing coronary thrombosis in a more or less high percentage of patients according to the record of cases taken into account. In our experience, more then thrombotic disease, found only in 13.4 % of patients, we detected a high prevalence and incidence of mild to severe aortic stenosis, found in 25.5 % of the sample studied. About all possible causes of stenosis, nowadays this results dependent of Ht values at moment of diagnosis, in the light of these results, it is reasonable to infer that aortic valve stenosis could depend by high haemodynamic stress on valve that is characteristic of polycythemic patients without chemotherapy.