LVH may decrease the height of R waves in the right precordial leads, sometime producing QS complexes in the absence of MI. In addition, LVH may prolong the duration of Q waves, again producing a false positive sign for MI.

Anterior MI:

Infarct location	ECG lead	Criterion	Specificity (%)
Inferior	II	Q > 40 msec	100
	aVF	Q > 40 msec R/Q < 2	98 95
Anterolateral	I	Q > 40 msec	96
Apical	V4	R/Q < 1 Notched R	95
Posterior	V2	R > 60 msec	99

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