Self-expanding transcatheter aortic valve replacement in patients with extremely horizontal aortas

Objectives To evaluate the feasibility of self-expanding transcatheter aortic valve replacement (TAVR) in patients with aortic stenosis and extremely horizontal aortas (aortic angulation >= 70 degrees). Background As TAVR using a self-expanding prosthesis is an off-label treatment for patients with extremely horizontal aortas, these patients are often excluded from randomized controlled trials involving self-expanding TAVR. Methods This study enrolled 27 consecutive patients with extremely horizontal aortas who underwent self-expanding TAVR for severe aortic stenosis. Results The patients' average age was 76.4 years, with a median Society of Thoracic Surgeons score of 4.53%. The device success and 30-day mortality rates were 66.7% and 7.4%, respectively. The sinotubular junction (STJ) was significantly smaller in the device success group (p = 0.001). The receiver operating characteristic curve analysis found that the area under the curve was 0.907 (95% confidence interval: 0.790-1.000, p = 0.001), validating the association between STJ diameter and device success. An optimal cutoff of 33.6 mm was determined using the Youden index, with a sensitivity and specificity of 88.9% and 77.8%, respectively. The device success rate was significantly higher (93.3% vs. 33.3%, p = 0.003) in patients with STJ diameters <= 33.6 mm (n = 15). In the subgroup analyses, severe valve calcification (n = 9) was associated with a higher incidence of moderate or severe paravalvular leakage (44.0% vs. 0%, p = 0.008), while a higher rate of second valve implantation (60.0% vs. 9.1%, p = 0.030) was found in patients with less than moderate valve calcification (n = 5). Conclusion Self-expanding TAVR could be suitable for patients with extremely horizontal aortas after careful preoperative evaluation.