Abstract P371: Short-term Repeatability of the Peguero Electrocardiographic Index of Left Ventricular Hypertrophy

Abstract

Background: Electrocardiographic left ventricular hypertrophy (ECG-LVH) represents preclinical cardiovascular disease and predicts cardiovascular disease and mortality. Current criteria include the Cornell voltage, Sokolow-Lyon, and the newly developed Peguero index (S D + SV 4 ). While the Peguero index has been shown to have better prognostic prediction compared with current criteria, its short term repeatability remains uncertain. Objectives: Characterize the repeatability and minimal detectable change of the Peguero ECG-LVH index. Methods: Participants (n=63; mean age 50 years; 31 females) underwent two standardized visits one week apart. At each visit, trained and certified technicians obtained two ECGs following a standardized protocol. The Epidemiological Cardiology Research Center automatically processed the ECGs using GE Marquette GE 12-SL software (GE, Milwaukee, WI) to obtain the Peguero (S D + SV 4 ) LHV index, defined as the deepest S wave in any single lead S D + SV 4 . We created a dichotomous using the following cut points: >2.3 mV for women and >2.8 mV for men. Random effects, mixed models were used to parse the variance of the index into the between-participant, between-visit, and within-visit components. We then calculated the intra-class correlation coefficient (ICC), Kappa coefficients, and minimal detectable change (95% confidence) between repeat measures. Results: Between-participant variation accounted for 93.58% (262,958 out of 280,985 SD points) of the total variation of the Peguero LVH index, while between-visit variation and within-visit variation were 5.51% (15,480 out of 280,985 SD points) and 0.91% (2,547 out of 280,985 SD points), respectively. The index had an ICC (95% confidence interval) of 0.94 (0.91-0.97) and a minimum detectable change value of 372.16 mV. Within visit Kappas were 0.79 (0.40-1.00) for the first visit and 1.00 (1.00-1.00) for the second visit. Between visit Kappas were 0.77 (0.70-0.84) for the first measurements of each visit and 0.79 (0.72-0.86) for the second measurements of each visit. Conclusion: The Peguero LVH index shows excellent repeatability for both within and between visits. The ICC and resulting confidence interval of the continuous index suggests near perfect agreement between groups. The Kappa values also suggest concurrence between groups of the dichotomous index, although the measures are not as precise as the ICC measure. The repeatability of this measure can be used to inform clinical and epidemiological studies and expand research of this novel index of ECG-LVH.