Platelet Secretion Defects and Acquired von Willebrand Syndrome in Patients With Ventricular Assist Devices.
BACKGROUND
The number of implanted ventricular assist devices (VADs) has increased significantly recently. Bleeding, the most frequent complication, cannot be solely attributed to anticoagulation therapy. Acquired von Willebrand syndrome (AVWS) caused by increased shear stress is frequent in VAD patients and can increase the bleeding risk. The HeartMate III (HM III) is a novel left VAD featuring potential improvements over the HeartMate II.


METHODS AND RESULTS
In this study, we investigated the prevalence and onset of AVWS in 198 VAD patients. To our knowledge, this is the largest cohort of VAD patients whose longitudinal data on AVWS have been collected. We also analyzed whether AVWS is less severe in HM III patients than in HeartMate II patients. Because platelet dysfunction can raise the bleeding risk, we investigated platelet function in a subset of patients. In total, 198 VAD patients and 60 patients with heart transplants as controls were included in this study. The ratio of von Willebrand factor collagen binding capacity to von Willebrand factor:antigen, multimer analyses, and platelet function (especially secretion of α- and δ-granules) were investigated. All 198 VAD patients developed AVWS. As soon as the VAD was explanted, the AVWS disappeared within hours. AVWS was less severe in the HM III patients than in the HeartMate II patients. The HM III patients had fewer bleeding symptoms. In addition, VAD patients exhibited a platelet α- and δ-granule secretion defect.


CONCLUSIONS
AVWS develops in VAD patients and may increase the bleeding risk. The HM III device causes less severe AVWS. Platelet secretion defects should be investigated in VAD patients because they also raise the bleeding risk.


CLINICAL TRIAL REGISTRATION
https://www.drks.de/drks_web. Unique identifier: DRKS00000649.
['Geisen|Ulrich|U|', 'Brehm|Kerstin|K|', 'Trummer|Georg|G|', 'Berchtold-Herz|Michael|M|', 'Heilmann|Claudia|C|', 'Beyersdorf|Friedhelm|F|', 'Schelling|Johannes|J|', 'Schlagenhauf|Axel|A|', 'Zieger|Barbara|B|']
D000328:Adult D000368:Aged D015415:Biomarkers D001792:Blood Platelets D016022:Case-Control Studies D005260:Female D005858:Germany D006333:Heart Failure D006353:Heart-Assist Devices D006470:Hemorrhage D006801:Humans D008137:Longitudinal Studies D008297:Male D008875:Middle Aged D010979:Platelet Function Tests D015995:Prevalence D012307:Risk Factors D055571:Secretory Pathway D012720:Severity of Illness Index D013997:Time Factors D016896:Treatment Outcome D016277:Ventricular Function, Left D014842:von Willebrand Diseases
platelet ventricular assist device von Willebrand factor