Editing Tetralogy of Fallot (section)

=== Electrocardiogram ===
An electrocardiogram (ECG) is one of the most basic procedures for assessing the heart.<ref name="Woods_1952">{{cite journal | vauthors = Woods A | title = The electrocardiogram in the tetralogy of Fallot | journal = British Heart Journal | volume = 14 | issue = 2 | pages = 193–203 | date = April 1952 | pmid = 14916062 | pmc = 479443 | doi = 10.1136/hrt.14.2.193 }}</ref> Tiny electrodes are applied to specific areas on the body, near the chest, arm, and neck. Lead cables connect the electrodes to an ECG machine. The heart's electrical activity is then measured.<ref name="Woods_1952" /> Natural electrical impulses help maintain blood flowing properly by coordinating contractions in different areas of the heart.<ref name="Woods_1952" /> These impulses are recorded by an ECG, which shows how fast, the rhythm, intensity and timing of the electrical impulses as they travel through the heart.<ref name="Woods_1952" />

Electrocardiography shows right ventricular hypertrophy (RVH), along with right axis deviation.<ref name="Francois_2016" /> RVH is noted on EKG as tall R-waves in lead V1 and deep S-waves in lead V5–V6.<ref>{{Cite web|date=2018-08-01|title=Right Ventricular Hypertrophy (RVH) • LITFL • ECG Library Diagnosis|url=https://litfl.com/right-ventricular-hypertrophy-rvh-ecg-library/|access-date=2019-01-21|website=Life in the Fast Lane|language=en-US|archive-date=2019-01-22|archive-url=https://web.archive.org/web/20190122044412/https://litfl.com/right-ventricular-hypertrophy-rvh-ecg-library/|url-status=live}}</ref>