Rwave

Rwave, or R-wave, is a term used in electrocardiography to describe the positive deflection found within the QRS complex of an electrocardiogram (ECG). It represents ventricular depolarization, the electrical activation of the heart’s ventricles that precedes their contraction.

In a typical 12-lead ECG, the R wave is the first upward spike after the P wave and any initial Q wave, though its appearance can vary by lead. The amplitude and polarity of the R wave depend on heart orientation, chest anatomy, and lead placement. A common feature in precordial leads is normal R-wave progression, where the R-wave amplitude increases from V1 to V5 or V6; deviations from this pattern can indicate underlying pathology or technical factors.

Clinical significance of the R wave includes its use in measuring heart rate via the R–R interval, as well as in diagnosing conditions. Abnormalities in R-wave progression, unusually large or small R waves, or changes over time can contribute to diagnoses such as left ventricular hypertrophy, prior myocardial infarction, conduction abnormalities, or ischemia. Changes in R-wave amplitude across leads can help localize cardiac events and assess ventricular function, though they are considered alongside other ECG findings.

Detection and analysis of the R wave rely on signal processing and sometimes automated ECG analysis algorithms. Challenges include noise, motion artifacts, and baseline wander, which may complicate R-peak identification. Proper electrode placement and filtering improve accuracy in both clinical settings and research.

See also: QRS complex, P wave, T wave, R–R interval, left ventricular hypertrophy.