CHỈ SỐ V3R/V7 TRONG XÁC VỊ TRÍ KHỞI PHÁT NGOẠI TÂM THU THẤT CÓ NGUỒN GỐC TỪ ĐƯỜNG RA THẤT TRÁI VÀ ĐƯỜNG RA THẤT PHẢI

Abstract

Background: The site of origin of ventricular arrhythmias (VAs) from the left ventricular- outflow tract (LV-OT) conducts the potential to V3R more clearly, and the RV-OT conducts the potential to V7 more clearly. Therefore, the combined use of R-wave ratios in V3R and V7 could improve the distinction between the origin of RV-OT and LV-OT. Objectives: To evaluate the diagnostic value of the V3R/V7 index in predicting the origin of ventricular arrhythmias from the LV-OT and the RV-OT. Subjects & methods: 58 patients of idiopathic ventricular arrhythmias with indications for electrophysiological testing (RFCA) as recommended by ACC/AHA/ESC in 2006, ESC recommendations in 2015 and expert consensus by EHRA/HRS in 2009. Results: Majority of patients VAs with origin of RV-OT (74.1%), average age is 50.5 years old, the rate of female is higher than that of male (69.0% vs 31.0%). The V3R/V7 index has good value in the differential diagnosis of VAs with origin of RV-OT and LV-OT with the area under the curve (UAC) of 0.80 (0.62-0.97). With value V3R/V7 ≥ 0.73; diagnosed with LV-OT with origin of left ventricular outflow tract with a sensitivity of 66.7% and a specificity of 100%. Conclusion: V3R/V7 index has good value in differential diagnosis of right ventricular outflow tract and left ventricular outflow tract.