The impact of position changes of the inflow cannula in LVAD patients

Left ventricular assist device inflow cannula malposition can contribute to numerous negative outcomes after device implantation. We analyzed the impact of position changes in the inflow cannula angle in HeartMate II (HM II) and HeartMate 3 (HM 3) patients.

Between January 2012 and December 2023, patients who underwent HM II and HM 3 implantation were reviewed. Among them, patients with suitable chest X-rays for angle calculation at both 1-2 months and 6-12 months post-implantation were identified.

The study cohort consisted of 66 (82.5%) HM 3 and 14 (17.5%) HM II patients. The median age of the cohort was 57.6 years (Interquartile range [IQR], 47.4-63.2), and the majority were males (n=73, 91.2%). Operative data and demographics were similar between the groups except for the body surface area (p<0.01), body mass index (p=0.01) and hypertension (p=0.02). A significant increase in the inflow cannula coronal angle was observed in the HM 3 group (p=0.03), while the pump depth distance remained similar (p=0.37). In contrast, the HM II group showed no significant changes in the inflow cannula angle (p=0.39) or the pump body angle (p=0.32). The HM 3 group exhibited a significant increase in pump power and pulstility index over time (p<0.01 and p=0.02, respectively).

A significant increase in the coronal angle of the inflow cannula over time was observed in HM 3 patients. Proper assessment of pump positioning at implantation is important, especially in hypertensive and overweight patients, as changes in pump angle over time may influence pump parameters.