NHibernate.ISQLQuery qry =
    session.CreateSQLQuery("SELECT Patients.last_name, Patients.patient_id, Patients.birth_date, Tests.acquisition_date, Tests.signature_date, Tests.signature, Tests.id_test, Tests.test_type FROM Tests INNER JOIN Patients ON Tests.id_patient = Patients.id_patient WHERE Tests.Enabled = 1");

ViewedTests result = new ViewedTests();
foreach (object[] item in qry.List())
{
    result.Add(new ViewedTest()
    {
        LastName = (String)item[0],
        Patient_id = (String)item[1],
        Birth_date = (DateTime?)item[2],
        Acquisition_Date = (DateTime?)item[3],
        Signature_Date = (DateTime?)item[4],
        Signature = (String)item[5],
        Id = (Int32)item[6],
        CodeTest = (Int32)item[7]
    });
}
return result;