Diagnostic accuracy of exercise electrocardiogram in patients with left anterior hemi-block.

Background: Left anterior hemiblock (LAHB) is the most frequent conduction abnormality, but its impact on the diagnostic accuracy of the exercise ECG has not been studied. The aim of our study was to determine the diagnostic accuracy of ST depression for predicting ischaemia in the presence of LAHB.

Patients: Consecutive patients with known or suspected coronary heart disease undergoing exercise ECG and 99mTc-sestamibi single photon emission computed tomography (SPECT) were included in the analysis.

QR in V1--an ECG sign associated with right ventricular strain and adverse clinical outcome in pulmonary embolism.

Aims: To test the hypothesis that Qr in V(1)is a predictor of pulmonary embolism, right ventricular strain, and adverse clinical outcome.

Methods And Results: ECG's from 151 patients with suspected pulmonary embolism were blindly interpreted by two observers. Echocardiography, troponin I, and pro-brain natriuretic peptide levels were obtained in 75 patients with pulmonary embolism.