Measurement of physical work capacity in patients with chronic aortic regurgitation: a potential improvement in patient management

Abstract

Timing of surgery in aortic regurgitation (AR) is important. Exercise testing is recommended upon uncertainty about functional limitations but reports on cardiopulmonary exercise testing (CPET) in populations with pure chronic AR are scarce. Twenty-eight patients referred for surgery because of chronic AR (13 in NYHA I, 10 in NYHA II and five in NYHA III) were tested by CPET pre- and 6 months postoperatively. Echocardiography, with measurement of left ventricular ejection fraction (LVEF), diameters (LVED, LVES) and volumes (LVEDV, LVESV) was also performed. The patients had normal LVEF pre- and postoperatively. LV diameters and volumes diminished significantly postoperatively (LVED from 67 to 57, LVES from 49 to 41 mm; P < 0.001). The majority of the patients had a 'low' physical work capacity, none of them performed better than 'average' according to Astrand's classification preoperatively and there was no significant postoperative improvement. The mean peak oxygen uptake (VO(2peak)) was 25 ml kg(-1) min(-1) both pre- and postoperatively, and six of the 28 patients had a VO(2peak) of less than 20 ml kg(-1) min(-1). VO(2peak) was not significantly related to NYHA class. LVEF, diameters and volumes at rest did not fulfil the criteria for surgery in most of our AR patients, of whom 46% were asymptomatic. However, many had a remarkably low work capacity, which was neither improved 6 months postoperatively nor correlated to echocardiographic LV dimensions. CPET predicted the postoperative work capacity and may, therefore, be a useful complement for timing of surgery in patients with chronic AR.