Superiority of the limb leads over the precordial leads on the 12-lead ECG in monitoring fluctuating fluid overload in a patient with congestive heart failure.

A 78-year old woman with congestive heart failure had fluctuating peripheral edema and weights while hospitalized and was subsequently followed in the cardiac clinic. Sums of the amplitudes of the QRS complexes for the leads I + II (SigmaQRS(I + II)), the 6 limb leads (SigmaQRS(6L)), the 6 precordial leads (SigmaQRS(V1-V6)), and all 12 leads (SigmaQRS(12L)) were calculated. Analysis showed that SigmaQRS(I + II) and SigmaQRS(6L) correlated very well with corresponding weights (r = 0.78, P .01 and r = 0.75, P = .02, respectively), whereas SigmaQRS(V1-V6) and SigmaQRS(12L) did not (r = 0.20, P = .60 and r = 0.47, P = .20, respectively). The reason for the poor correlation of the latter two was the erratic values of SigmaQRS(V1-V6) in serial electrocardiogram recordings. SigmaQRS(I + II) and SigmaQRS(6L) are useful for serially following patients with congestive heart failure and peripheral edema.