Expanded Use of the VPCML Oxygenator

The Variable Prime Cobe Membrane Lung (VPCML) is a membrane gas exchange device originally developed for the short term cardiopulmonary support of infants and small adults. A particular advantage is its low static priming volume of 425 cc. To assess the efficacy of the VPCML in heavier patients, we used it for cardiopulmonary bypass in 123 consecutive adult patients weighing 47-120 kg (mean 78 ± 15 kg). Arterial and venous blood gases were obtained simultaneously at maximum hypothermia and during rewarming. Venous pO2 was used to assess the adequacy of perfusion. Mean venous pO2 during rewarming between the 60–70 kg group (n=22) and the 90–100 kg group (n=17) was 38±8 mmHg and 38±6 mmHg respectively (p = NS). Our results, with a mean flow of 3.79 ± 0.39 LPM, showed excellent gas exchange at maximum hypothermia and during rewarming regardless of weight range. In summary, our experience with the VPCML oxygenator demonstrates its ability to safely and efficiently oxygenate a wide range of adult patients while keeping priming volume to a minimum

Neurological Events Following Transcatheter Aortic Valve Replacement and Their Predictors: A Report From the CoreValve Trials

The risk for stroke after transcatheter aortic valve replacement (TAVR) is an important concern. Identification of predictors for stroke is likely to be a critical factor aiding patient selection and management as TAVR use becomes widespread. Patients enrolled in the CoreValve US Extreme Risk and High Risk Pivotal Trials or Continued Access Study treated with the self-expanding CoreValve bioprosthesis were included in this analysis. The 1-year stroke rate after TAVR was 8.4%. Analysis of the stroke hazard rate identified an early phase (0-10 days; 4.1% of strokes) and a late phase (11-365 days; 4.3% of strokes). Baseline predictors of early stroke included National Institutes of Health stroke scale score >0, prior stroke, prior transient ischemic attack, peripheral vascular disease, absence of prior coronary artery bypass surgery, angina, low body mass index (<21 kg/m(2)), and falls within the past 6 months. Significant procedural predictors were total time in the catheterization laboratory or operating room, delivery catheter in the body time, rapid pacing used during valvuloplasty, and repositioning of the prosthesis. Predictors of stroke between 11 and 365 days were small body surface area, severe aortic calcification, and falls within the past 6 months. There were no significant imaging predictors of early or late stroke. Predictors of early stroke after TAVR included clinical and procedural factors; predictors of later stroke were limited to patient but not anatomic characteristics. These findings indicate that further refinement of imaging to identify anatomic factors predisposing to embolization may help improve stroke prediction in patients undergoing TAVR. URL: http://www.clinicaltrials.gov. Unique identifiers: NCT01240902, NCT01531374

Open Atrial Transcatheter Mitral Valve Replacement in Patients With Mitral Annular Calcification

BACKGROUND: Mitral valve replacement in the setting of severe mitral annular calcification remains a surgical challenge. Transcatheter mitral valve replacement (TMVR) using an aortic balloon-expandable transcatheter heart valve is emerging as a potential treatment option for high surgical risk patients. Transseptal, transapical, or transatrial access is not always feasible, so an understanding of alternative implantation techniques is important. OBJECTIVES: The authors sought to present a step-by-step description of a contemporary transatrial TMVR technique using balloon-expandable aortic transcatheter heart valves. This procedure has evolved over time to address valve migration, left ventricular outflow tract obstruction, and paravalvular leak. The authors present a refined technique that has been associated with the most reproducible outcomes. METHODS: A step-by-step description of the TMVR technique and outcomes of 8 patients treated using this technique are described. Baseline patient clinical and echocardiographic characteristics and 30-day post-TMVR outcomes are presented. RESULTS: Eight patients underwent transatrial TMVR at a single institution. Five had previous cardiac surgery. Mean STS score was 8%. Technical success by MVARC (Mitral Valve Academic Research Consortium) criteria was 100%. There was zero in-hospital and 30-day mortality. Procedural success by MVARC criteria at 30 days was 100%. Paravalvular leak immediately post-implant was none or trace in 6 and mild in 1. CONCLUSIONS: The technique described is reproducible and was associated with favorable outcomes in this early experience. It represents a useful technique for the treatment of mitral valve disease in the setting of severe annular calcification. A structured and defined implantation technique is critical to investigators as this field evolves