Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content +++ ECG Findings ++ Wide QRS complex > 120 ms. rsR’ pattern in leads V1 and V2. Slurred S wave in lateral leads (I, aVL, V5-V6). ST depression and T-wave inversion is typical in the right precordial leads (V1-V3). When all of these criteria are met except that the QRS duration is < 120 ms, an incomplete right bundle branch block (RBBB) pattern is diagnosed. +++ Pearls ++ In RBBB, conduction through the right bundle is delayed, whereas depolarization through the left bundle occurs at normal speed. This creates a secondary R wave (an rsR’ pattern), ST depression, and T-wave inversion in the right precordial leads (V1-V3), as well as a slurred S wave in the lateral leads. Acute right heart strain, as may occur with pulmonary embolism, may result in the appearance of an incomplete or complete RBBB pattern. ++ FIGURE 23.19A Right Bundle Branch Block. (ECG contributors: Clifford L. Freeman, MD, and Nicole S. McCoin, MD.) Graphic Jump LocationView Full Size||Download Slide (.ppt) ++ FIGURE 23.19B Note the rsR’ pattern in V1 (arrowheads), the inverted T wave (arrow), and the QRS duration greater than 120 ms (double arrow). Graphic Jump LocationView Full Size||Download Slide (.ppt) Your MyAccess profile is currently affiliated with '[InstitutionA]' and is in the process of switching affiliations to '[InstitutionB]'. Please click ‘Continue’ to continue the affiliation switch, otherwise click ‘Cancel’ to cancel signing in. Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Username Error: Please enter User Name Password Error: Please enter Password Forgot Username? Forgot Password? Sign in via OpenAthens Sign in via Shibboleth