Background: To evaluate the effect of high altitude on pulmonary hypertension and surgical morbidity, comparison has been done between two group of the patients undergone mitral valve replacement due to rheumatic mitral stenosis.

Methods: The Group I was consisting of 50 patients living in average 1750 m altitude, and the Group II was also containing 50 patients living in near sea level altitude. Both groups were analyzed retrospectively to compare perioperative and postoperative findings. Mechanical mitral valve protheses were implanted to all patients in both groups.

Results: Average age, sex, length and severity of symptoms, functional capacity, mitral valve area and gradients, presence of moderate or severe tricuspid regurgitation were nonsignificant between two groups. Systolic pulmonary artery pressure (PAP) was 64 ± 13 mmHg and mean PAP 31 ± 7 mmHg in Group I, and they were 49 ± 11 mmHg and 21 ± 5 mmHg in Group II (p < 0.01). Left atrial size was 6.3 ± 1.4 cm in Group I, and 4.8 ± 0.7 cm in Group II (p < 0.01). The operative characteristics such as valve implantation technique, cardioplegia delivery, cross clamp’s length, left atrial thrombectomy, tricuspid valve reconstruction, inotropic support and hospital mortality were found nonsignificant between two groups.

Conclusions: Although the high-altitude resident’s left atrial size and PAP were found higher than Group II, in our opinion, to living at high altitude does not effect directly the peroperative results and the complications.

Keywords : High altitude, pulmonary hypertension, mitral stenosis, valve replacement, left atrium