ABSTRACT
Introduction Left ventricular assist devices (LVAD) are used as a bridge to heart transplant or destination therapy for patients with the New York Heart Association (NYHA) class 3 or 4 heart failure. Acute kidney injury (AKI) or need for renal replacement therapy (RRT) post-LVAD implant can lead to poor outcomes. Identifying risk factors of AKI post-LVAD implant can help stratify potential LVAD candidates. Methods This is a retrospective study of all patients who received continuous-flow LVAD at our institution from January 2015 until August 2017. We calculated the incidence of AKI and the need for RRT post-LVAD implant, as well as the rate of renal recovery and survival rates at 30 days and 1-year post-LVAD implant. The presence of chronic kidney disease (CKD) and proteinuria was assessed, and kidney ultrasound results were reviewed on all patients, if available. CKD was present if estimated glomerular filtration rate (eGFR) was <60 mL/min per 1.73m2 for ≥3 months preceding LVAD implant and/or presence of proteinuria ≥ 20 mg/dL on two or more urine samples prior to LVAD implant and/or an abnormal kidney ultrasound with increased echogenicity, small size <9 cm or scarring. AKI was defined as per the current Kidney Disease Initiative Global Outcomes (KDIGO) guidelines. Results A total of 137 patients received LVAD during this time period. There were 112 males and 25 females with a mean age of 59.2 years. Incidence of AKI and the need for RRT post-LVAD implant were 64% and 19.7%, respectively. Sub-group analysis was performed based on the presence of CKD, advanced CKD stage (Stage 1-2 vs 3-5), proteinuria and abnormal kidney ultrasound. The incidence of AKI post-LVAD implant was significantly higher if baseline CKD was present (P = 0.028), and patient had an advanced CKD stage (P = 0.008). The need for RRT post-LVAD implant was significantly higher if baseline CKD was present (P = 0.015), and the patient had an abnormal kidney ultrasound (P = 0.04). Thirty-day and one-year mortality rates post-LVAD implants were 4.3% and 21.1%, respectively for the entire cohort. Out of the 27 patients requiring RRT, nine (33.3%) came off RRT before one year. Compared to the eGFR on the day of LVAD implant, eGFR at 30 days post-LVAD implant was higher in 57% and lower in 42% patients. At one year, this eGFR improvement reversed and eGFR was lower in 67% and higher in 32% patients. Conclusion The incidence of AKI and need for RRT post-LVAD implant are very high. The presence of CKD, advanced CKD stage, and an abnormal kidney ultrasound are statistically significant risk factors of AKI post-LVAD implant and/or need for RRT. Identifying these renal risk factors can help stratify the potential LVAD candidates. Only one out of three patients requiring RRT achieved dialysis independence by one-year post-LVAD implant.
ABSTRACT
Unregulated traditional medications and their solvents are nephrotoxic. We present a case of a 49-year-old Nigerian male with a 10-year history of diabetes mellitus and hypertension who was ingesting a traditional, herbal medication as an aphrodisiac for erectile dysfunction. He had a rapid decline in kidney function over a period of one year and the patient commenced thrice weekly hemodialysis. He came to the USA for a second opinion. A full laboratory evaluation for immunologic and infectious causes of kidney failure was unremarkable. Kidneys were 12 cm bilaterally and a kidney biopsy revealed protracted tubular injury with isometric vacuolization and numerous calcium oxalate crystals. His serum oxalate level was elevated and there was no evidence of primary hyperoxaluria. It was suspected that the daily use of traditional, herbal supplements which often contain ethylene or diethylene glycol-based solvents may have led to a chronic oxalate toxicity that resulted in his kidney failure and above-mentioned pathological findings. Kidney damage was deemed irreversible and the patient returned to Nigeria. Worldwide, the increasing use of unregulated traditional, herbal supplements has the potential to cause epidemics of kidney disease in rural communities. A thorough medication history including the use of traditional and herbal supplements should be obtained in all patients with a rapid decline in kidney function, even in the presence of known risk factors for chronic kidney disease (CKD).
