Refractory ventricular tachycardia caused by inflow cannula mechanical injury in a patient with left ventricular assist device: Catheter ablation and pathological findings

Association of Inflow Cannula Position with Left Ventricular Unloading and Clinical Outcomes in Patients with HeartMate II Left Ventricular Assist Device

The relationship between the HeartMate II left ventricular assist device (LVAD) position and pump thrombosis has been reported. However, further clinical implications of device position are unknown. This study aimed to investigate optimal device position for better left ventricular (LV) unloading and patient prognosis. Patients undergoing a ramp test with right heart catheterization after HeartMate II LVAD implantation were enrolled to this study. Device position was quantified from the chest X-ray obtained at the time of the ramp test: (1) inflow cannula angle relative to horizontal line, (2) pump angle relative to spine, (3) pump depth, (4) angle between inflow cannula and pump, and (5) angle between pump and outflow graft. LV unloading was assessed by pulmonary capillary wedge pressure at set LVAD speed. Fifty-four patients (60 years old and 34 male [63%]) were enrolled. Nobody experienced device malfunction during the study period. Increased LV unloading (i.e., lower pulmonary capillary wedge pressure) was associated with a narrower inflow cannula angle relative to horizontal line. Inflow cannula angle <75° was associated with higher 1 year heart failure readmission-free survival rate (p < 0.05, hazards ratio 7.56 [95% confidence interval 2.32-24.7]). In conclusion, HeartMate II LVAD inflow cannula position was associated with LV unloading and patient prognosis. Prospective studies to ensure optimal device positioning and target better clinical outcomes are warranted.

Chronic Heart Failure Treatment With the Left Ventricular Assist Device

The prevalence of chronic heart failure is increasing in the United States due to the increase in the number of older adults and because many people are surviving acute cardiac events and living longer with chronic heart disease. In end-stage heart failure, heart transplant was once the gold standard of treatment and patients had to wait for a matching heart donor. In the past, the left ventricular assist device (LVAD) was a mechanical circulatory support treatment used temporarily for those awaiting heart transplant. However, the LVAD is increasingly becoming the chosen treatment of patients in lieu of heart transplant. Home healthcare nurses and clinicians need to be familiar with LVADs in order to care for patients in end-stage heart failure who are using these devices. This article explains the mechanism, potential complications, and nursing implications of caring for the patient who is using an LVAD.