Valve-in-Valve Transcatheter Aortic Valve Replacement Versus Redo-Surgical Aortic Valve Replacement in Patients With Aortic Stenosis: A Systematic Review and Meta-analysis.

Aortic stenosis is a common and significant valve condition requiring bioprosthetic heart valves with transcatheter aortic valve replacement (TAVR) being strongly recommended for high-risk patients or patients over 75 years. This meta-analysis aimed to pool existing data on postprocedural clinical as well as echocardiographic outcomes comparing valve-in-valve (ViV)-TAVR to redo-surgical aortic valve replacement to assess the short-term and medium-term outcomes for both treatment methods. A systematic literature search on Cochrane Central, Scopus, and Medline (PubMed interface) electronic databases from inception to August 2023. We used odds ratios (OR) for dichotomous outcomes and mean differences (MD) for continuous outcomes. Twenty-four studies (25,216 patients) were pooled with a mean follow-up of 16.4 months. The analysis revealed that ViV-TAVR group showed a significant reduction in 30-day mortality (OR 0.50, 95% confidence interval [CI] 0.43 to 0.58, p <0.00001), new-onset atrial fibrillation (OR 0.34, 95% CI 0.17 to 0.67, p = 0.002), major bleeding event (OR 0.28, 95% CI 0.17 to 0.45, p <0.00001) and lower rate of device success (OR 0.25, 95% CI 0.12 to 0.53, p = 0.0003). There were no significant differences between either group when assessing 1-year mortality, stroke, myocardial infarction, postoperative left ventricular ejection fraction, and effective orifice area. ViV-TAVR cohort showed a significantly increased incidence of paravalvular leaks, aortic regurgitation, and increased mean aortic valve gradient. ViV-TAVR is a viable short-term option for older patients with high co-morbidities and operative risks, reducing perioperative complications and improving 30-day mortality with no significant cardiovascular adverse events. However, both treatment methods present similar results on short-term to medium-term complications assessment.

Appraisal of radioactivity and associated radiation hazards in sand samples of four rivers of Punjab province, Pakistan.

Natural and anthropogenic radioactivity of sand and water samples collected from the four big rivers of Punjab province, Pakistan, was measured using a high-purity germanium detector coupled with a high resolution multichannel analyser. The average concentration of the naturally occurring radionuclides (226)Ra, (232)Th and (40)K in all the sand samples from the rivers Jhelum, Chenab, Ravi and Indus was found to be 22±0.6, 36±1 and 287±10 Bq kg (-1), respectively, while the concentration of the anthropogenic radionuclide (137)Cs was found to be below the minimum detectable activity, i.e. ~1.2 Bq kg (-1). All the sand samples have Ra(eq) concentrations lower than the limit of 370 Bq kg (-1). Indoor (H (in)) and outdoor (H (out)) radiation hazard indices were calculated for the samples to assess the radiation hazards arising due to the use of this sand in construction, and were found to be less than unity in the study area. Calculated values of the absorbed dose rate were less than the typical world average value of 59 nGy h (-1), and the annual effective dose rate was also less than the typical world value of 70 µSv, except in the Indus river, in which it is slightly higher then the world average. Results show that the measured values are comparable with other global radioactivity measurements. None of the studied riverbeds was considered a radiological hazard, and their sand can be safely used in construction.