Electrocardiographic (ECG) criteria for detecting left ventricular hypertrophy (LVH) are integral to clinical decision-making.¹ Although these methods are quick to apply, low cost, and widely available, their sensitivity is modest.² Multiple voltage-based criteria exist, such as the Sokolow-Lyon, Cornell, and Peguero-Lo Presti criteria, but accurate use often requires familiarity with several indices and can be time-consuming for trainees. Simple, reliable markers could improve the efficiency and consistency with which ECGs are flagged as possibly indicating LVH.

The S-wave amplitude in lead V3 (SV3) is a plausible single-lead marker. It is a component of the Cornell criterion (SV3 + RaVL),³ and it is closely related to the Peguero-Lo Presti criterion (SV4 plus the deepest precordial S).⁴ Because the largest precordial S wave often occurs in V3, a single SV3 measurement could serve as a rapid screening tool to identify the presence of established LVH criteria, especially for those with less experience interpreting ECGs.

The aim of this study was not to propose a new LVH criterion but rather to determine whether a single measurement, the SV3 amplitude, can accurately identify the presence of any established LVH ECG criterion.

We conducted a retrospective analysis of a 12-lead ECG dataset from the PhysioNet repository.^5,6 The database provides standard ECG tracings with limited demographic and clinical information.

Of 294 ECGs screened, 204 met eligibility criteria and were included in the analysis. A total of 58 participants were women. The cohort's median age was 57 years (± 14). Baseline characteristics are summarized in Table 1. Participant flow is shown in Figure 1.

The AUC for SV3 was 0.8170 (95% CI, 0.7557-0.8783), which indicates good discriminative ability. The optimal cutoff was ≥ 13 mm. At this threshold, sensitivity was 74.7% (95% CI, 64.4%-82.8%) and specificity was 78.5% (95% CI, 70.4%-84.9%). The positive likelihood ratio (LR+) was 3.476 and the negative likelihood ratio (LR−) was 0.32. The ROC curve is presented in Figure 2.

Using a cutoff of ≥13 mm for the S wave in lead V3 to flag the presence of established LVH ECG criteria demonstrated practical value. The associated positive and negative likelihood ratios supported clinical utility, offering a fast, single-lead screening approach that may be especially useful for less experienced interpreters and can streamline ECG assessment for LVH-related features.

This cutoff is not a diagnostic criterion for LVH itself; rather, it indicates the likely presence of at least one established LVH ECG criterion. The use of an anonymized, publicly available dataset may have limited access to complete clinical information for some patients, although cases with incomplete data were excluded. The retrospective design and reliance on a database not originally constructed for hypothesis-driven research may also constrain generalizability. Prospective validation in diverse populations is warranted.

A single-lead SV3 cutoff of ≥13 mm demonstrated good diagnostic accuracy and practical utility for identifying the presence of LVH-related ECG criteria. This simplified approach enables rapid, reliable screening—particularly useful for less experienced clinicians—without requiring familiarity with multiple complex indices.