The Carmat Bioprosthetic Total Artificial Heart Is Associated With Early Hemostatic Recovery and no Acquired von Willebrand Syndrome in Calves.

OBJECTIVES: To determine hemostasis perturbations, including von Willebrand factor (VWF) multimers, after implantation of a new bioprosthetic and pulsatile total artificial heart (TAH). DESIGN: Preclinical study SETTING: Single-center biosurgical research laboratory. PARTICIPANTS: Female Charolais calves, 2-to-6 months old, weighing 102-to-122 kg. INTERVENTIONS: Surgical implantation of TAH through a mid-sternotomy approach. MEASUREMENTS AND MAIN RESULTS: Four of 12 calves had a support duration of several days (4, 4, 8, and 10 days), allowing for the exploration of early steps of hemostasis parameters, including prothrombin time; coagulation factor levels (II, V, VII+X, and fibrinogen); and platelet count. Multimeric analysis of VWF was performed to detect a potential loss of high-molecular weight (HMW) multimers, as previously described for continuous flow rotary blood pumps. Despite the absence of anticoagulant treatment administered in the postoperative phase, no signs of coagulation activation were detected. Indeed, after an immediate postsurgery decrease of prothrombin time, platelet count, and coagulation factor levels, most parameters returned to baseline values. HMW multimers of VWF remained stable either after initiation or during days of support. CONCLUSIONS: Coagulation parameters and platelet count recovery in the postoperative phase of the Carmat TAH (Camat SA, Velizy Villacoublay Cedex, France) implantation in calves, in the absence of anticoagulant treatment and associated with the absence of decrease in HMW multimers of VWF, is in line with early hemocompatibility that is currently being validated in human clinical studies.

Clinical Outcome of First- vs Second-Generation DES According to DAPT Duration: Results of ARCTIC-Generation.

There is an apparent benefit with extension of dual antiplatelet therapy (DAPT) beyond 1 year after implantation of drug-eluting stents (DES). Assessment by a Double Randomization of a Conventional Antiplatelet Strategy vs a Monitoring-Guided Strategy for Drug-Eluting Stent Implantation, and of Treatment Interruption vs Continuation One Year After Stenting (ARCTIC)-Generation assessed whether there is a difference of outcome between first- vs second-generation DES and if there is an interaction with DAPT duration in the ARCTIC-Interruption study. ARCTIC-Interruption randomly allocated 1259 patients 1 year after stent implantation to a strategy of interruption of DAPT (n = 624), in which aspirin antiplatelet treatment only was maintained, or DAPT continuation (n = 635) for 6 to 18 additional months. The primary endpoint was the composite of death, myocardial infarction, stent thrombosis, stroke, or urgent revascularization. A total of 520 and 722 patients received a first- and a second-generation DES, respectively. After a median follow-up of 17 months (interquartile range, 15-18 months) after randomization, the primary endpoint occurred in 32 (6.2%) and 19 (2.6%) patients with first- and second-generation DES, respectively (hazard ratio: 2.31, 95% confidence interval: 1.31-4.07, P = 0.004). This was observed irrespective of the strategy of interruption or continuation of DAPT and timing of study recruitment. Major bleeding events occurred in 4 (0.8%) and 3 patients (0.4%) with first- and second-generation DES, respectively (hazard ratio: 1.79, 95% confidence interval: 0.40-8.02, P = 0.44). Results did not change after multiple adjustments for potential confounding variables. ARCTIC-Generation showed worse clinical outcome with first- vs second-generation DES, a difference that appeared to persist even with prolonged DAPT.