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Malfunction of a continuous-flow left ventricular assist device (CF-LVAD) due to device thrombosis is a potentially life-threatening event that currently presents a diagnostic challenge. We aimed to propose a practical echocardiographic assessment to diagnose LVAD malfunction secondary to pump thrombosis.Among 52 patients implanted with a CF-LVAD from a single center who underwent echocardiographic pump speed-change testing, 12 had suspected pump thrombosis as determined by clinical, laboratory, and/or device parameters. Comprehensive echocardiographic evaluation was performed at baseline pump speed and at each 1,000-rpm interval from the low setting of 8,000 rpm to the high setting of 11,000 rpm in 11 of these patients.Receiver operating characteristic curves and stepwise logistic regression analyses showed that the best diagnostic parameters included changes in the LV end-diastolic diameter (0.6 cm), aortic valve opening time (80 msec), and deceleration time of mitral inflow (70 msec) from lowest to highest pump speed. One parameter was predictive of pump malfunction, with 100% sensitivity and 89% specificity, whereas 2 of 3 parameters increased the sensitivity to 100% and specificity to 95%.The 3 echocardiographic variables of measured changes in LV end-diastolic diameter, aortic valve opening time, and deceleration time of mitral inflow between the lowest (8,000 rpm) and highest pump speed settings (11,000 rpm) during echo-guided pump speed-change testing appear highly accurate in diagnosing device malfunction in the setting of pump thrombosis among patients supported with CF-LVAD. Further investigation is warranted to create and validate a prediction score.

Purpose Inflow cannula malposition (ICM) is a major concern in Left Ventricular Assist Device patients (LVAD).We propose a quantitative classification of IC position by cardiac Computed Tomography (CCT) to assist in the diagnosis of IC malposition. Methods and Materials In 16 consecutive LVADs-Pts (14 Heart-Mate II) underwent 64 slices CCT. IC position was measured during mid diastole by: 1) acute angle between the long axis of the IC and the long axis of the left heart perpendicular to the mitral annulus plane and 2) distance between the IC tip and the opposing LV wall. The IC position was deemed: 1) Appropriate: if angle is 1cm. 2) Intermediate: if angle is between 31-60° and the distance > 1cm. 3) Malposition: if angle is >60° or the distance Results The mean age was 55±14 yrs, 50 % male and 60% had ischemic cardiomyopathy. Pts were divided into 2 groups according to the clinical presentation. Group 1 were 6 pts with suspected IC malposition (frequent LVAD alarm, low output, recurrent VT, and hemolysis ) and group 2 were 10 pts with non IC related indication (source of emboli/infection, effusion/hematoma, and 2 LV function/aortic valve assessment). Group 1 had higher LVAD-LV angle and shorter LVAD-LV distance as compared to Group 2 (63±6° vs 35 ± 12 ° p =0.001, 0.6±0.5 cm vs 3.5±2.3 cm P= 0.02). All pts with clinically suspected ICM were deemed to have ICM as determined by CCT. [ figure 1 ] Conclusions ICM can be detected by quantitative measurements in CCT, further studies are needed.