| Objective To research characteristics of the electrocardiogram(ECG) and electrocardiogram vector(ECG vector) in idiopathic ventricular premature contractions originating from right ventricular outflow tract(RVOT) and aortic sinus cusp(ASC).Methods: 1. All the patients has been confirmed for frequent ventricular premature beat by the the standard 12-lead ECG and 24 hours dynamic electrocardiogram(ECG), and a course of 1 year or more.structural heart disease was excluded.2. According to the result of radiofrequency ablation,all the patients was divided into two parts :the aortic sinus cusp and right ventricular outflow tract.Further the ROVT was divided into the right ventricular outflow tract septum and free wall, the ASC was divided into three parts:the Left coronary cusp(LCC)the Right coronary cusp(RCC) the junction of Left coronary cusp(LCC) Right coronary cusp(RCC).Analysis the characteristic of five parts of different origin Such as:The V2 Transition Ratio V2 lead R-wave duration index and V2 lead R/S amplitude index ?transitional zone(TZ) index in precordial?Analysis the starting 0.01 s to 0.01 s vector Angle and the largest vector orientation and amplitude and other characteristicsof QRS loop, Understand the characteristics of the vectorcardiogram premature beatoringinate of different parts.3. comparing the difference of The V2 Transition Ratio V2 lead R-wave duration index and V2 lead R/S amplitude index ?transitional zone(TZ) index in precordial between ventricular premature beat comes from different orig, and calculate the sensitivity and specificity, etc.Analysis of the difference of ventricular premature beat vectorcardiogram between the starting 0.01 s to 0.04 s space vector angle and the largest vector orientation vector Angle / amplitude,whitch comes from different parts.Results: 1. 27 patients with an average age of 46.1 + /- 16.7, 15 ~ 63 years old,The male to female ratio was 11/16, average number of 24 h dynamic electrocardiogram was 33101.6 + /-12377.1,average of left ventricular ejection fraction(%) was 60.3 + /- 5.2(%), Patients with different origin and sex had no statistical significance in left ventricular ejection fraction and the number of PVCs in 24 h.2.The surface12-lead ECG showed a left bundle branch block pattern.The precordial transition ratio?V4 lead and transition zone index>0 predicted the ROVT origin.V2 lead R-wave duration index?50%,and V2 lead R/S amplitude index?30% ?V2 Transition Ratio>0.6 predicted the ASC origin?3.In all the 27 patients, there were 9 patients(33.3%) showing CW QRS-loop shapes separately in the F plane, and CCW is 13(48.1%)patients, CW8 3patients(11.1%),CCW8 2 patients(7.4%) Respectively. there were 15 patients(55.6%) showing CCW and 8 patients showing CCW8 of the QRS loops in the H plane and 26 patients(96.3%) were exhibiting CW QRS-loop in S plane.CONCLUSION:1.All premeature ventricular contractions origin from ROVT and ASC showed a left bundle branch block pattern in the surface12-lead ECG. The use of precordial transition ratio?V4 lead?transition zone index >0 predicted the ROVT origin,V2 lead R-wave duration index?50%,and V2 lead R/S amplitude index?30%,V2 Transition Ratio>0.6 predicted the ASC origin is useful.2.The pattern of ventricular premature beat come from Right outflow tract and the aortic sinus cusp is different from left bundle branch block, which the spot at the starting portion and eccentric branch of vectorcardiogram are dense but scattered in the returning branch in the premature ventricular contractions.But in left bundle branch block, spot dense is in the central QRS loop and returning branch.3.the difference in QRS loop starting vector, vector amplitude and Angle betweeen ventricular premature beat come from Right ventricular outflow tract and aortic root had no statistical significance, speculated that the ventricular premature beat come from right ventricular outflow tract and the ventricular premature beat come from aortic sinus of cusp both were left bundle branch block and inferior axis. |
PDF Full Text Request