Prognostic value of a new intravascular ultrasound score in graft vessel disease

Abstract

Coronary angiography has a low sensitivity for the detection of graft vessel disease (GVD). Consequently, intravascular ultrasound (IVUS) is increasingly used for this purpose. Severity of GVD is graded with the Stanford classification, that takes into consideration only the most diseased spot of the entire coronary tree (range 0-IV). With the aim of including also the extent of the disease and the presence of fibrosis or calcification (density) of the lesions, we designed a score ‘S’ according to the following formula: S(0-10)5Stanford class(0-4)1 mean intimal index(04)1density(0-2) where intimal index 5 intimal area/vessel area. In 1998, a retrospective comparison of Stanford and ‘S’ scores in a group of 30 transplant recipients showed superiority of ‘S’ score in all sensitivity (Sens), specificity (Spec), positive and negative predictive values (1PV and -PV), and diagnostic efficacy (DxEf), when both parameters were used to predict major clinical events (MACE) in mid-term follow-up. This study consists of a prospective validation of ‘S’ in a series of 82 recipients followed for 22613 months, among which 23 MACE (14 deaths, 4 retransplants, 5 revascularizations) were recorded. When compared to class IV of the Stanford system, the presence of a ‘s’.7 implied the occurrence of a MACE with a Sens570%, Spec566%, 1PV544%, -PV585%, DxEf567%, while the corresponding values for Stanford54 are Sens583%, Spec530%, 1PV532%, -PV582% and DxEf545%. Conclusion: In comparison with Stanford classification, ‘S’ score showed better features for prediction of MACE in heart transplant recipients.