Outcomes in patients with aortic stenosis and severely reduced ejection fraction following surgical aortic valve replacement and transcatheter aortic valve replacement.

BACKGROUND: Patients with severe aortic stenosis (AS) and left ventricular (LV) dysfunction demonstrate improvement in left ventricular injection fraction (LVEF) after aortic valve replacement (AVR). The timing and magnitude of recovery in patients with very low LVEF (≤ 25%) in surgical or transcatheter AVR is not well studied. OBJECTIVE: Determine clinical outcomes following transcatheter aortic valve replacement (TAVR) and surgical aortic valve repair (SAVR) in the subset of patients with severely reduced EF ≤ 25%. METHODS: Single-center, retrospective study with primary endpoint of LVEF 1-week following either procedure. Secondary outcomes included 30-day mortality and delayed postprocedural LVEF. T-test was used to compare variables and linear regression was used to adjust differences among baseline variables. RESULTS: 83 patients were enrolled (TAVR = 56 and SAVR = 27). TAVR patients were older at the time of procedure (TAVR 77.29 ± 8.69 vs. SAVR 65.41 ± 10.05, p < 0.001). One week post procedure, all patients had improved LVEF after both procedures (p < 0.001). There was no significant difference in LVEF between either group (TAVR 33.5 ± 11.77 vs. SAVR 35.3 ± 13.57, p = 0.60). Average LVEF continued to rise and increased by 101% at final follow-up (41.26 ± 13.70). 30-day mortality rates in SAVR and TAVR were similar (7.4% vs. 7.1%, p = 0.91). CONCLUSION: Patients with severe AS and LVEF ≤ 25% have a significant recovery in post-procedural EF following AVR regardless of method. LVEF doubled at two years post-procedure. There was no significant difference in 30-day mortality or mean EF recovery between TAVR and SAVR. TRIAL REGISTRATION: Indiana University institutional review board granted approval for above study numbered 15,322.

Heparin Dosing During Percutaneous Coronary Intervention and Obesity.

ABSTRACT: Unfractionated heparin is the most common anticoagulant used during percutaneous coronary intervention. Practice guidelines recommend an initial weight-based heparin bolus dose between 70 and 100 U/kg to achieve target activated clotting time (ACT) of 250-300 seconds. The impact of severe obesity on weight-based heparin dosing is not well studied. We performed a retrospective analysis of 424 patients undergoing percutaneous coronary intervention who received heparin for anticoagulation. We collected detailed data on cumulative heparin administration and measured ACT values in this cohort. We performed separate analyses to identify clinical predictors that may affect dose-response curves. There was significant variability in dosing with mean dose of 103.9 ± 32-U/kg heparin administered to achieve target ACT ≥ 250 seconds. Women received higher initial heparin doses when adjusted for weight than men (97.6 ± 31 vs. 89 ± 28 U/kg, P = 0.004), and only 49% of patients achieved ACT ≥ 250 s with the initial recommended heparin bolus dose (70-100 U/kg). Lower heparin dose (U/kg) was required in obese patients to achieve target ACT. In multivariate linear regression analysis with ACT as dependent variable, after inclusion of weight-based dosing for heparin, body mass index was the only significant covariate. In conclusion, there is significant variability in the therapeutic effect of heparin, with a lower weight-adjusted heparin dose required in obese patients.