A ventricular assist device as a bridge to recovery, decision making, or transplantation in patients with advanced cardiac failure

Early thrombus formation in patient with HeartWare left ventricular assist device presenting with acute heart failure

Heart failure is one of the leading causes of mortality and morbidity in the world. Heart transplantation is still the gold standard therapy despite emerging treatment options. Due to the limited number of available donors, the use of ventricular assist devices has increased. However, increasing incidences of complications are observed with using these devices. In this article, surgical treatment of a huge mobile thrombus formation in an inflow cannula due to ineffective anticoagulation in a 59 year-old man who received a HeartWare ventricular assist device because of ischemic cardiomyopathy is presented.

Evaluation of a Spiral Groove Geometry for Improvement of Hemolysis Level in a Hydrodynamically Levitated Centrifugal Blood Pump

The purpose of this study is to evaluate a spiral groove geometry for a thrust bearing to improve the hemolysis level in a hydrodynamically levitated centrifugal blood pump. We compared three geometric models: (i) the groove width is the same as the ridge width at any given polar coordinate (conventional model); (ii) the groove width contracts inward from 9.7 to 0.5 mm (contraction model); and (iii) the groove width expands inward from 0.5 to 4.2 mm (expansion model). To evaluate the hemolysis level, an impeller levitation performance test and in vitro hemolysis test were conducted using a mock circulation loop. In these tests, the driving conditions were set at a pressure head of 200 mm Hg and a flow rate of 4.0 L/min. As a result of the impeller levitation performance test, the bottom bearing gaps of the contraction and conventional models were 88 and 25 μm, respectively. The impeller of the expansion model touched the bottom housing. In the hemolysis test, the relative normalized index of hemolysis (NIH) ratios of the contraction model in comparison with BPX-80 and HPM-15 were 0.6 and 0.9, respectively. In contrast, the relative NIH ratios of the conventional model in comparison with BPX-80 and HPM-15 were 9.6 and 13.7, respectively. We confirmed that the contraction model achieved a large bearing gap and improved the hemolysis level in a hydrodynamically levitated centrifugal blood pump.

TandemHeart Device as Rescue Therapy in the Management of Acute Heart Failure

<p><b>Background:</b> The TandemHeart device (THD) is a pump system that can be deployed percutaneously (PC) or via conventional surgical (CS) cannulation; it is capable of supporting one or both ventricles. It is a versatile system designed for use as a rescue device in acute heart failure and as a bridge to decision in moribund patients.</p><p><b>Methods:</b> Retrospective analysis was conducted on all patients who underwent a THD implant; either PC or CS; at our institution. Univariate analysis was done using Fisher's exact and Chi-square tests for categorical variables and Wilcoxon Rank Sum test for continuous ones.</p><p><b>Results:</b> 51 adult patients were identified: 10 PC and 41 CS. Mean age was 58.9 � 12.8 years, and 31% were female. In hospital mortality was 61%. Univariate predictors of death were prolonged support (74% versus 46%, <i>P</i> = .04) and higher lactic acid levels (5.3 � 4.9 versus 2.3 � 1.9 mmol/L, <i>P</i> = .012). The length of stay (LOS) for survivors was 59.8 � 30.0 days.</p><p><b>Conclusion:</b> Uni- or bi-ventricular unloading can be successfully achieved using the THD, either trans-thoracically or percutaneously, with an acceptable complication profile.</p>