title: Factors determining immediate and medium-term results after pulmonary balloon valvuloplasty.
abstract: OBJECTIVE
  To determine factors influencing immediate and medium-term results of Pulmonary Balloon Valvuloplasty (PBV) for pulmonary valve stenosis.
  
  
  METHODS
  Between 1995 and 2001, the authors carried out PBV in 25 consecutive patients. Two treatment outcomes including immediate and medium-term results were analyzed. The immediate results were classified into two groups based on the pulmonary systolic pressure gradient (PG) immediately after dilation: group 1 with a PG < or = 35 mmHg and group II with a PG > 35 mmHg. At medium-term follow-up of 6 to 60 months, echocardiographic evaluations were analyzed and divided into two groups: group A with a PG < or = 25 mmHg and group B with a PG > 25 mmHg. Demographic characteristics and hemodynamic parameters of immediate and medium-term results were compared and analyzed.
  
  
  RESULTS
  Immediately after PBV the right ventricular systolic pressure (RVSP) decreased from 115.3 +/- 37.6 mmHg to 67.0 +/- 28.5 mmHg (p < 0.001). The pulmonary systolic pressure gradient decreased from 90.4 +/- 37.9 mmHg to 39.3 +/- 25.6 mmHg (p < 0.001). Nine of the 25 patients (group 11; 36%), with incomplete immediate relief of the obstruction, had more symptoms, a higher baseline PG, higher right atrial pressure, higher RVSP, and a higher systolic pressure ratio. Six of the 25 patients (group B; 24%), with suboptimal medium-term results, had a higher right ventricular voltage on the electrocardiogram, higher pre-dilation PG, and higher RVSP.
  
  
  CONCLUSIONS
  Successful medium-term outcomes following pulmonary balloon valvuloplasty were achieved in 76% of the patients, with a greater success rate (91%) in patients with a lower right ventricular voltage electrocardiogram (R wave amplitude in V1) < or = 21 mm, a prevalvuloplasty systolic gradient < or = 90 mmHg, and right ventricular systolic pressure < or = 125 mmHg.
authors.affiliation: Division of Cardiology, Department of Pediatrics, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand. ssamana@mail.med.cmu.ac.th
authors.forename: Suchaya
authors.initials: S
authors.lastname: Silvilairat
authors.forename: Yupada
authors.initials: Y
authors.lastname: Pongprot
authors.forename: Rekwan
authors.initials: R
authors.lastname: Sittiwangkul
authors.forename: Charlie
authors.initials: C
authors.lastname: Phornphutkul
mesh_terms: D000293:Adolescent; D001794:Blood Pressure; D002404:Catheterization; D002648:Child; D002675:Child, Preschool; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011666:Pulmonary Valve Stenosis / Q000503:physiopathology / Q000628:therapy*; D013997:Time Factors