As the number of LVAD-supported patients continues to increase, treatment of unusual complications emanating from LVAD implantations becomes more essential. We present here four cases of patients with rare complications following LVAD implantation and their management.
One of the complications of prolonged use of LVAD is the development and progression of de novo aortic regurgitation3. Significant AR reduces LVAD output and leads to end-organ mal-perfusion and recurrence of heart failure symptoms. Furthermore, AR affects patient survival4. Treatment of late symptomatic AR in LVAD-supported patients represents a real challenge. Surgical aortic valve replacement is associated with increased mortality. While percutaneous aortic valve closure with an Amplatzer occlude device has been reported, significant residual regurgitation has been observed5. TAVI poses a potential therapeutic option for patients with late AR development following LVAD implantation. One reported case from Germany demonstrated the feasibility of transapical TAVI treatment in patients with severe AR after LVAD implantation6. Our group reported the first in-human transfemoral TAVI for severe AR in a patient with LVAD7. We report here the long-term echocardiographic results following transfemoral TAVI in LVAD-supported patients. Our patient underwent TAVI on August 8, 2012. The last echocardiography, performed 56 months after the procedure, showed a well-functioning bio-prosthetic aortic valve without any valvular insufficiency.
Cable damage associated with pump failure is one of the most severe complications after LVAD implantation. This malfunction usually appears at the proximal portion close to the pump body8. While an accidental powerful pull on the cable, weight gain and active lifestyle, all reflect improvement of the patient's clinical condition, it could also be responsible for lead damage. Recently, due to the improvements of the driveline design, the incidence of cable damage has been significantly reduced. Moazem et al.reported a decrease in the incidence of cable damage from 4.2–1.2% after modification of the lead design9. In our case, the alarm and X-ray allowed for fast diagnosis of the cable damage. Transthoracic echocardiography excluded cannula malposition, significant aortic valve disease and thrombus in the left ventricle. Case B patient underwent an uneventful urgent exchange of the main pump body with the remaining inflow and outflow conduits. There were no intraoperative complications. Despite the well-functioning LVAD, the patient died on post-operative day 7 due to respiratory failure. In non-emergent cases, pump replacement can be performed safely with operative mortality < 7%9. C-shaped tunneling and cable looping of the driveline prevent accidental cable pulling and damage. Transcutaneous energy sources, which are in advanced stages of development, may solve the problem of cable damage completely in the future. Our group together with others performed the first in-human LVAD implantation using wireless energy transfer technology10.
Uterine myomas are the most common benign uterine tumors that occur in 20–25% of women at the reproductive age11. However, they rarely cause acute complications, such as acute vaginal or intra-peritoneal hemorrhage, which can be associated with significant morbidity and mortality. Anticoagulation, which is mandatory for preventing pump thrombosis, may increase the risk of uterine bleeding12.
Case C patient was admitted 15 days after discharge with massive vaginal bleeding. We started treatment with GnRH analogues, but despite performing a pelvic angiography, we could not identify the source of the bleeding. While GnRH has been used recently to achieve hypoestrogenism both as primary conservative therapy for myomas and as an adjunct to myomectomy, its effects are transient, and the myomas usually return to pre-therapy size within a few months of discontinuation13. The bleeding ceased and our patient was discharged. Two weeks later, she was re-admitted in stable condition with massive vaginal bleeding. She underwent eventless emergent open hysterectomy after the correction of INR. Laparoscopic hysterectomy was not an option due to the emergency of the case and the reduced function of the right ventricle. During laparoscopic surgery, pneumoperitoneum is necessary to allow adequate exposure. Pneumoperitoneum reduces cardiac output due to direct compression to the inferior vena cava causing reduced preload14. Urine artery embolization has been used for the treatment of hemorrhaging that complicates the course of uterine myoma. However, the procedure is compromised by the high rates of post-procedural complications and high rates (28–32%) of re-intervention15.There were no complications following hysterectomy and the patient was discharged five days after the procedure.The patient was 2.5 years without vaginal bleeding, during which time she was under treatment with aspirin and Coumadin maintaining a therapeutic level of INR. Heart transplant was performed in August 2018, and her post-transplant course was uneventful.
While today most LVAD patients are managed as outpatients, their follow-up is complex. In addition to INR management, it is also necessary to monitor several flow parameters of the device. Monitoring of the speed, power consumption and blood flow is mandatory. Any changes in these three key parameters will alert both the patient and the physician to abnormalities in the LVAD function. Our patient (Case D) had display failure one month after LVAD implantation. Even after connecting the patient to an external screen, we were unable to receive information about pump speed, power consumption and blood flow. Experts from the company were unable to solve this rare problem. Device replacement is not an entirely harmless procedure and is associated with increased risk of morbidity and mortality9. Since our patient was asymptomatic we decided to continue follow-up clinically and echocardiographically, and to place him at the top of the waiting list for a heart transplant. He was discharged after one week of observation in our department, and asked to be in close contact with us. He monitored his symptoms, weight and edema daily, and after 11 months underwent heart transplantation. The post-transplant course was uneventful.
According to the company, the reason for the display failure was due to a communication error between the patient's system controller and the LVAD pump. It triggered a communication fault advisory alarm on the system controller. The company associated the error to manufacturing variances from a single supplier that could have led to crystallization formation, which may then have disrupted communication between the pump and the system controller. The company has updated the specification and manufacturing process to ensure that this error does not re-occur during HeartMate III device manufacturing.
Conclusion: The incidence of LVAD complications not related to gastrointestinal bleeding and infections is variable and generally unexpected. It is important to know these complications and their management.