Comparison of outcome of higher versus lower transvalvular gradients in patients with severe aortic stenosis and low (<40%) left ventricular ejection fraction

Left ventricular systolic dysfunction in patients with severe aortic stenosis (AS) is associated with poor outcome. This analysis was designed primarily to describe the clinical course of a large series of consecutive patients with severe AS and low ejection fraction (EF) (<40%) who, because of high surgical risk, were referred for transcatheter aortic valve implantation consideration. A cohort of 270 patients with severe AS and low EF (<40%) who were referred to participate in a clinical trial of transcatheter aortic valve implantation was studied. Clinical, hemodynamic, and periprocedural complications and follow-up mortality data were collected and compared between patients with low mean transvalvular gradients (≤40 mm Hg, n = 170 [63%]) and high transvalvular gradients (>40 mm Hg, n = 100 [37%]). Patients with low gradients were younger (mean age 79.8 ± 9.1 vs 83.8 ± 7.7 years, p <0.001) and had higher incidences of coronary artery disease and renal failure. Mean aortic valve area was larger (0.73 ± 0.23 vs 0.53 ± 0.18 cm(2), p <0.001), while mean EF (26.4 ± 6.9% vs 30.5% ± 6.6%, p <0.001), cardiac output (3.7 ± 1.1 vs 4.1 ± 1.3 L/min, p = 0.04), and cardiac index (1.9 ± 0.5 vs 2.1 ± 0.6 L/min/m(2), p = 0.04) were lower in patients with lower gradients compared to those with higher gradients, respectively. Mortality was higher in patients with low gradients (53.8%) at a mean follow-up of 151 days compared to those with high gradients (41%) at a mean follow-up of 256 days (p = 0.01). In conclusion, patients with severe AS and low EF with low transvalvular gradients are at higher risk for worse outcomes compared to patients with high transvalvular gradients. Surgery or transcatheter aortic valve implantation treatment and high baseline transvalvular gradient are associated with EF improvement.     

The risk of tuberculosis in transplant candidates and recipients: a TBNET consensus statement

Tuberculosis (TB) is a possible complication of solid organ and hematopoietic stem cell transplantation. The identification of candidates for preventive chemotherapy is an effective intervention to protect transplant recipients with latent infection with Mycobacterium tuberculosis from progressing to active disease. The best available proxy for diagnosing latent infection with M. tuberculosis is the identification of an adaptive immune response by the tuberculin skin test or an interferon-γ based ex vivo assay. Risk assessment in transplant recipients for the development of TB depends on, among other factors, the locally expected underlying prevalence of infection with M. tuberculosis in the target population. In areas of high prevalence, preventive chemotherapy for all transplant recipients may be justified without immunodiagnostic testing while in areas of medium and low prevalence, preventive chemotherapy should only be offered to candidates with positive M. tuberculosis-specific immune responses. The diagnosis of TB in transplant recipients can be challenging. Treatment of TB is often difficult due to substantial interactions between anti-TB drugs and immunosuppressive medications. This management guideline summarises current knowledge on the prevention, diagnosis and treatment of TB related to solid organ and hematopoietic stem cell transplantation and provides an expert consensus on questions where scientific evidence is still lacking.