Comparison of Myocardial Loading Between Asynchronous Pulsatile and Nonpulsatile Percutaneous Extracorporeal Life Support

Abstract

We hypothesized that myocardial loading can be increased when extracorporeal pulse flow occurs during systole, and that this may adversely affect myocardial working conditions in heart failure patients supported by extracorporeal life support (ECLS). This study was designed to compare myocardial loading and myocardial oxygen consumption/supply balance between nonpulsatile ECLS and asynchronized pulsatile ECLS in a myocardial stunning model. Thirteen, 23-42 kg dogs were allotted to a nonpulsatile group and an asynchronous pulsatile group. Coronary sinus lactate level, mixed venous oxygen consumption (MvO2), and left anterior descending coronary artery flow were measured. The real-time pressure of the left ventricle and the ascending aorta was monitored, and the lowest left ventricular pressure and tension time index were calculated. Our results showed that the lactate level and the lowest left ventricular pressure were lower in the pulsatile group than in the nonpulsatile group at 30 minutes after ECLS was applicated (p < 0.05, respectively). Tension time index in the pulsatile ECLS group was substantially lower than in the nonpulsatile group. Left anterior descending coronary flow did not show significant difference between the two groups. In conclusion, asynchronous pulsatile ECLS may also be superior to nonpulsatile ECLS in myocardial volume unloading and oxygen consumption/supply balance.

Echocardiographic assessment of flow across continuous-flow ventricular assist devices at low speeds

“…10 Despite this difference in the characteristic of the device, continuous-flow devices provide an equivalent degree of hemodynamic support, LV unloading, end-organ perfusion and exercise capacity to pulsatile LVADs. [11][12][13][14][15] Successful assessment of the underlying myocardial function in patients with LVADs can only occur after minimizing the device's contribution to the circulation to ensure that LV loading is a physiologic response to the reduction of the LVAD support. In practical terms, this occurs when the mechanical support is either reduced or discontinued.…”

Coronary versus carotid blood flow and coronary perfusion pressure in a pig model of prolonged cardiac arrest treated by different modes of venoarterial ECMO and intraaortic balloon counterpulsation

“…It is well described that besides the primary cardiac disease, nonpulsatile ECMO flow may adversely affect cardiac performance in critical states, including hypoxemic blood perfusion of the coronary circulation due to a pulmonary dysfunction [21], changes in load-dependent contractile function [22] and pure mechanical negative effect on LV function [23]. A controversial effect on afterload changes has also been described [24,25]. It appears that cannulation selection, that is, subclavian/carotid arterial ECMO cannula position and the magnitude of bypass flow also play a critical role in coronary blood flow, depending on the distance from the coronary arteries, and thus, "availability" of the oxygenated blood [26-28].…”

Three cases of electrical storm in fulminant myocarditis treated by extracorporeal membrane oxygenation

“…ECMO support provides sufficient coronary perfusion for myocardium as well as adequate blood and oxygen for other important organs. These acute respiratory distress syndrome (22). As a result, ECMO has been associated with both patient and mechanical complications; including stroke (8%), brain death (6%), hemorrhage (cannula, 27%; pulmonary, 10%), infection (15%), and a need for dialysis (16%) (23).…”