BACKGROUND: Pulmonary hypertension (PH) may be associated with subendocardial ischaemia. We investigated whether ischaemia-modified albumin (IMA), an established marker of ischaemia, is elevated in stable patients with PH. METHODS: We studied 32 patients with PH and an equal number of age-matched normal volunteers. We assessed serum IMA levels with the albumin cobalt-binding test. RESULTS: Patients' mean +/- SD (range) pulmonary arterial pressure was 56 +/- 12 (33-73) mmHg and their exercise capacity was 394 +/- 145 (121-688) m in the 6-min walk test. IMA was 92 +/- 14 (69-115) U ml(-1) in the patient group and 93 +/- 9.4 (76-122) U ml(-1) in the control group with no significant difference between the two (p = 0.85), although almost one-third of the patients had detectable troponin-I. CONCLUSIONS: We conclude that IMA, a marker of ischaemia, does not differ in patients with advanced clinically stable PH compared with normal subjects.