The prognostic significance of horizontal plane QRS axis in elderly heart failure.

In order to investigate whether horizontal plane QRS axis predicts the prognosis in elderly heart failure, we studied 80 consecutive patients by clinical assessment, ECG, Doppler and echocardiography. All patients were followed up for 2 years, 12 died and 68 survived. Age, gender distribution, blood pressure, co-existing diagnoses and medication were all similar between those who died and those who survived. The NYHA classification was significantly worse, left ventricular (LV) cavity size was greater, LV systolic function was lower in those who died than in survivors, despite similar LV wall thickness. On ECG, heart rate, PR interval, QT interval and frontal QRS axis did not differ between the two groups. The QRS duration was significantly longer and the horizontal QRS axis projected to a substantially more posterior direction in those who died than in survivors. The sensitivity and specificity of a horizontal QRS axis < or =-30 degrees for predicting death in 2 years were 75% and 62%, respectively. The former is above the sensitivity of a NYHA > or =3 and the latter is above the specificity of a LV shortening fraction < or =20%. The combination of a QRS horizontal axis < or =-30 degrees and NYHA > or =3 predicted 2 year mortality with a sensitivity of 75% and specificity of 91%. In conclusion, a left posterior QRS axis of the horizontal plane in elderly heart failure indicates an adverse prognosis, particularly when combined with NYHA classification and echocardiographic assessment.