The 2009 “AHA/ACCF/HRS Recommendations for Standardization and Interpretation of the Electrocardiogram” (ECG) state that in the presence of left anterior fascicular block (LAFB), “R-wave amplitude in leads I and aVL are not reliable criteria forà” diagnosing left ventricular hypertrophy (LVH). This statement was based upon 3 relatively small studies published between 1976 and 1992 that used manual ECG measurements and included limited control groups. We sought to reexamine the validity of this statement in a larger study that incorporated adequate controls and computer-assisted ECG interpretation.
We searched our hospital ECG database (Marquette MUSE) for recordings in which LVH had been diagnosed by Sokolow index (R-wave amplitude in aVL > 11 mm) or Cornell criteria (cumulative amplitude of R-wave-aVL & S-wave-V3 > 28 mm in men and > 20 mm in women). Over a 20-month period, we identified 354 tracings (83 with LAFB, 271 without it) from patients in whom echocardiogram had been performed within 90 days of the ECG. We also identified 444 control subjects without ECG criteria for LVH for whom echocardiogram data were also available. The “gold standard” for LVH was left ventricular mass index on echocardiogram greater than 115 g/m2 in men (95 g/m2 in women).
In the presence of LAFB, compared to its absence, the two ECG criteria identified LVH with sensitivity of 34% (vs. 60%), specificity of 95% (vs. 77%) and positive predictive value of 78% (vs. 64%). Positive predictive value was 88% in men and 72% in women.
In the presence of LAFB, the Sokolow Index and the Cornell Criteria identify LVH with specificity and positive predicative value equivalent to other criteria that were included in the 2009 multi-society guidelines.
In the presence of LAFB there is approximately 80% certainty that fulfillment of either the Cornell Criteria or the Sokolow Index indicates the presence of anatomical LVH (by echocardiogram). The 2009 multi-society guidelines for ECG interpretation may have incorrectly eschewed these ECG criteria.
Vladimir Rukshin, No Financial Disclosure Information; No Product/Research Disclosure Information