A Novel Link between G6PD Deficiency and Hemolysis Events in Patients Supported with Continuous-Flow Left Ventricular Assist Devices
Continuous-flow left ventricular assist device (CF-LVAD) support is a well-established treatment for end-stage heart failure but little data are available on hemolysis complications. G6PD deficiency is associated with the development of hemolysis during states of high oxidative stress. No data exist on the role of G6PD deficiency in hemolysis during CF-LVAD support. The purpose of this study was to describe hemolysis in patients who have been implanted with a CF-LVAD. In particular, we sought to investigate the relationship of G6PD deficiency with clinical hemolysis events.
Methods and Materials
From October 2005 through October 2011, 85 patients with end-stage heart failure underwent implantation of a CF-LVAD at the University of North Carolina at Chapel Hill. Cases of hemolysis, G6PD deficiency and associated morbidity and mortality were validated by review of medical records. Univariable and multivariable analysis was used to determine independent predictors of hemolysis hospitalizations.
Hemolysis occurred in 13 patients (15%) with average follow-up of 9.9±8.2 months. G6PD levels were available in 34 patients (40%) and were low in 7 (20%), all of whom were blacks (p=0.007). Peak LDH levels at any time during post-LVAD follow-up period were higher in patients with low versus normal G6PD levels (8160±9526 vs. 2534±2919, p=0.01). There was a trend towards more hemolysis events in patients with low versus normal G6PD levels (57% vs. 19% p=0.06). Low G6PD level was the only variable significantly different between patients with and without post-LVAD hemolysis hospitalizations (57% vs. 11% p=0.001; OR 10.7 [95% CI: 1.6-73], p=0.02).
Hemolysis in CF-LVAD supported patients was not uncommon and resulted in important morbidity. To our knowledge, this study is the first to describe an association between low G6PD levels and hemolysis hospitalizations in CF-LVAD supported patients. More studies are needed to elucidate the mechanisms involved.
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