High R'/R in V1-2 leads represents right ventricular pressure and volume overload in ASD

  • Mr Motoki Takamuro, Department of Cardiology, Hokkaido Medical Center for Child Health and Rehabilitation, Japan
  • Mr Keiji Haseyama, Departement of Pediatrics, Sapporo Medical University, Japan
  • Mr King-ya Hatakeyama, Department of Cardiology, Hokkaido Medical Center for Child Health and Rehabilitation, Japan
  • Mr Norihisa Horita, Departement of Pediatrics, Sapporo Medical University, Japan
  • Miss Naomi Abe, Department of Cardiology, Hokkaido Medical Center for Child Health and Rehabilitation, Japan
  • Mr Masato Yokozawa, Department of Cardiology, Hokkaido Medical Center for Child Health and Rehabilitation, Japan

    • [Background] In atrial septal defect (ASD), electrocardiography (ECG) shows incomplete right bundle branch block pattern with high R’ voltage in lead V1.[Purpose] To evaluate relationship between R’ voltage in right precordial leads and volume / pressure overload in ASD.[Methods] Retrospective study. In catheterization cases, R and R’ voltage and R’/R in lead V1 to 3 were compared to Qp/Qs, mean pulmonary artery pressure, %RVEDV, RVEDV/LVEDV, hANP and BNP. With p value <0.05 as significance.[Patients] 33 cases with ASD. Age at catheterization was 1t o 20 (Median 7 ) years old. Male 15, Female18.
    [Results] Mean and standard deviation of each parameters were showed as follows; Qp/Qs 2.4±0.6, mPAP 17±6.9mmHg, %RVEDV 162±33%, hANP 43±38 ng/ml, BNP 28±23 ng/ml. R’/R were 3.8±2.2 in V1, 1.4±1.3 in V2, 0.5±1.0 in V3. In V3 lead, because over the half of cases have no R’, excluded V3 data. In both of V1 and V2, R’/R was correlated to mPAP, %RVEDV, RVEDV/LVEDV, hANP, BNP. However simple R’ voltage has no correlation to all parameters.[Discussion] In ASD, although R’ voltage in right precordial leads is not reflected to right heart overload, R’/R may predict pressure and/or volume overload of right ventricle. Correlation between R/R’ and pressure overload is better in V1 than V2. Even in statistically not significant, Qp/Qs has better R2 and p-value in V2 rather than V1. When right heart overload in ASD is discussed with ECG, V2 lead should be added to V1 in point of view.