Wright table of the cardiac cycle: Expanding application to clinical settings

Abstract

Purpose: Introduce a clinical variant of the Wright table both to teach at the upper undergraduate/graduate level and to model pathologies at the graduate/residency level of clinical training. Introduction:The cardiac cycle is taught in cardiovascular units and used by health professionals. The original Wright table (1) models this process’ events using four flow phases and four compartments. Its use of pressures in each compartment to drive blood from veins to arteries, with valve openings, closings, and heart sounds, was applied at the preclinical level. Improvements in the Wright table (2) include those for a right heart, a left heart with pulmonary wedge pressures, and some comparisons (e.g., right-vs-left heart). Preclinical medical students used these to model valvular pathologies (3). We hypothesized that if the Wright table included isovolumetric phases, it could be a clinical instrument to be used by cardiologists to help solidify key concepts necessary to understand pathology. Methods:A variant of this table was developed using five columns of “compartments” to model the cardiac cycle in the left heart: pulmonary veins, left atrium, left ventricle, aorta, and a pulmonary wedges concept that illustrates when blood backs up into pulmonary capillaries. The right heart’s includes a jugular venous compartment. This variant was pilot-demonstrated via zoom to a group of cardiologists to explore its potential use as an instrument to model pathologies. Results:The clinical variant of the Wright table displays all seven phases of the cardiac cycle typically depicted in the Wiggers diagram. The first phase, 1) rapid ventricular filling, begins when the A-V valve opens. This is followed by 2) slow ventricular filling [a.k.a. diastasis], 3) active ventricular filling during atrial systole, 4) isovolumetric contraction, 5) rapid ventricular ejection, 6) slow ventricular ejection [and protodiastole], and 7) isovolumetric relaxation. Each phase occupies one row from 1) top to 7) bottom, resulting in a 5-compartment, 7-phase (5x7) table of the cardiac cycle. The clinical variant of the Wright table puts all three ventricular filling phases together at the top prior to ventricular emptying. It introduces a system for pathophysiological modeling for both clinical professionals and advanced medical students. The model is constructed in a way that allows for a variety of comparisons including right-vs-left heart; physiological vs. pathological; early vs. late progression of a pathological condition; and earlier-to-later times. It also can display atrial and/or septal defects and their pathological effects within the heart. Conclusion:We present a clinical variant of the Wright table that was successfully tested with cardiologists. This all-phase variant shows its potential as a tool to deepen physiological and pathophysiological insight on the cardiac cycle to both advanced medical students and clinical professionals in a cardiology context. Funding: None This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.