Usefulness of electromagnetic flowmetry in intraoperative evaluation of aortic regurgitation associated with...

In 38 patients with aortic regurgitation (AR) associated with ventricular septal defect (VSD), indications for aortic valvuloplasty (AVP) or aortic valve replacement (AVR) were investigated by assessing AR ratio, which was measured by electromagnetic flowmetry of the ascending aorta during the operation. Residual AR was evaluated by auscultation postoperatively. Patients were assigned to group A if they underwent VSD closure alone and to group B if they underwent AVP in addition to VSD closure; patients who had no postoperative AR were assigned to group I and those with persistence of AR to group II. Thus, the patients were separated into 4 subgroups; A-I (9 patients), A-II (5 patients), B-I (20 patients) and B-II (4 patients). In subgroup A-I, mean AR ratio decreased from 9% to 7% postoperatively, in A-II from 19% to 16% (p less than 0.1), in B-I from 36% to 9% (p less than 0.01) and in B-II from 44% to 20% (p less than 0.05). An AR ratio of more than 25% should be regarded as an absolute indication for AVP or AVR. If the AR ratio is between 20 and 25%, the indication of AVP is determined by inspection of the aortic valve. A good correlation was found between AR ratio and the AR rate determined by the aortic angiographic findings (Sellers classification): grade I AR corresponded to an AR ratio of 5 to 15%, grade II to 20 to 35%, grade III to 25 to 50% and grade IV to 45% or higher (r = 0.87, p less than 0.01).