Left Ventricular Suction in Right Ventricular Dysfunction

Introduction and Objective:Recent research has determined that the "cardiac suction" phase occurs between systole and diastole.The aim of this work was to analyze the suction capacity of the left ventricle after excluding the right ventricle through an atriopulmonary bridge.Methods: An atriopulmonary bridge was performed on six dogs, followed by right coronary artery occlusion to generate right ventricular dysfunction.Cardiac output (CO), cardiac index (CI), systolic index (SI), left ventricular stroke work index (LVSWI), right ventricular stroke work index (RVSWI), systemic vascular resistance (SVR) and pulmonary vascular resistance (PVR) were evaluated using a Swan Ganz catheter.Recordings were acquired at baseline before any procedure, 60 minutes after right coronary occlusion with the atriopulmonary bridge connection closed and 60 minutes after opening the atriopulmonary connection.At the end of the experiment, coronary angiography and histological examination were performed to verify the right coronary occlusion.Results: Sixty minutes of coronary occlusion produced decreased CO (3.43 to 2.25 l/min), CI (5.22 to 3.39 l/m 2 ), SI (41.5 to 20.8 ml/beat/m2), LVSWI (53.3 to 14.4 g × m/beat/m 2 ), and RVSWI (1.61 to -1.97 g × m/beat/m 2 ).When the atriopulmonary bridge was opened, CO increased to 3.39 l/min (p<0.05),CI to 4.95 l/m 2 (p<0.05),SI to 45.1 ml/beat/m 2 (p<0.05),LVSWI to 40.8 g × m/beat/ m 2 (p<0.05) and RVSWI to 1.57 g × m/beat/m 2 (p<0.05), and right atrial pressure decreased from 10.6 to 3 mmHg (p<0.05) and PVR from 109 to 48.9 dyn/s/cm -5 (ns). Conclusion:As demonstrated by means of an atriopulmonary bridge, right ventricular dysfunction experimentally induced by ischemia is compensated by a left ventricular suction mechanism, restoring normal circulatory parameters.