Differential Diagnosis Of 80 Cases Wide QRS Complex Tachycardia

Objective: The morphological features of surface ECG of spontaneous wide QRS complex tachycardia were investigated,value of ECG Criteria for the differential diagnosis was evaluated. Mthods: The patients of tachycardia were selected while they were diagnoted, when tachycardia was diagnosed, P wave vanished and heart rate > 100 beat per minute and QRS time ≥ 120ms. After diagnosis being confirmed, the morphological features of 12-lead ECG were analyzed retrospectively, we selected for analysis those with ≥ 90% specificity and electro-physiological documentation of the tachycardias studied in the original publication, specification and sensitivity for each of the criteria were calculated and their practicality was evaluated. Results: To select 80 cases of wide QRS complex tachycardia, SVT 45 cases, VT 35 cases; According to the features of lead V1, they were divided into RBBB type and LBBB type. When the tachycardia was the RBBB type, the specificity of the left rabbit ear configuration in V1 lead and QS, QR, or R configuration in lead V6 and right superior axis reached 100%, sensitivity 22~44%. When the tachycardia was the LBBB type, the specification of the any q wave in lead V6 and notched downstroke S wave in lead V1 or V2 reached 100%, sensitivity 18~24%. The specification of the presence of a concordant pattern (entirely positive or negative QRS complexes) in all precordial leads and absence of an RS patterns in all precordial leads for RBBB type and LBBB type tachycardia reached to 100%, but sensi-tivity was low, 11~-17% and 6~12% respectively. Furthermore, the specification of the QRS duration > 140ms for RBBB type and LBBB type tachycardia was different dramatically, 97% and 36% respectively, P <0.01, and the difference was meaning in statistics. Conclusions: The morphological features of surface ECG were vital importance for differential diagnosis of wide QRS complex tachycardia. According to the morphological features in lead VI, tachycadias were divided into RBBB type and LBBB type, and then, with different type, selected some differential diagnosis criterias of higher specification, so can increase the efficiency and accuracy of diagnosis.