Photobiomodulation for Blood Pressure and Heart Rate Reduction in Mastectomized Women on Hormone Blockers: A Randomized Controlled Trial.

Objective: To assess the impact of intravascular laser irradiation of blood (ILIB) on the primitive carotid artery (PCA) hemodynamic variables, specifically blood pressure (BP) and heart rate (HR), in mastectomized patients undergoing hormone blocker treatments. Materials and methods: This study is a controlled, experimental, and randomized clinical trial. Patients were allocated into two groups: the experimental group (G1)-patients who received ILIB therapy using a 660 nm laser targeted at the PCA, and the control group (G2)-patients who did not receive ILIB therapy. Clinical research was conducted weekly, with measurements of systolic blood pressure (SBP), diastolic blood pressure (DBP), and HR. The Mann-Whitney U test for independent samples was used, with a significance level of α = 0.05. Results: Systemic photobiomodulation on the PCA did not demonstrate a statistically significant difference in relation to SBP and DBP. However, for HR, the p-value was <0.05, indicating a significant difference between G1 and G2. The initial mean p > decreased from 142.3 to 116.4 mmHg in G1, and from 130.4 to 119.8 mmHg in G2. The DBP varied from 78.8 to 72.8 mmHg in G1, and from 79.1 to 74.2 mmHg in G2. A statistically significant difference was observed in HR, decreasing from 81.3 to 62.06 bpm in G1, and changing minimally from 74.1 to 75.1 bpm in G2. A considerable reduction was present in the timing of application. Conclusions: ILIB therapy applied to the PCA induces a reduction in BP and, more notably, HR in mastectomized women using the tamoxifen or aromatase inhibitors.

Efectos de la estimulación cardiaca convencional. Estimulación en sitios alternativos / Effect of conventional cardiac pacing. Alternative pacing sites

Desde la primera publicación del abordaje transvenoso para la implantación de marcapasos en 1959, el ápex del ventrículo derecho ha sido el sitio tradicional de estimulación por ser de fácil acceso y proporcionar estabilidad a largo plazo y umbrales crónicos de estimulación óptimos. La estimulación en orejuela derecha y ápex de ventrículo derecho ha permitido establecer una frecuencia cardiaca estable y lograr la sincronía auriculoventricular, dos de los objetivos principales de la estimulación eléctrica extrínseca; sin embargo, con ello no se ha conseguido lograr un patrón de activación y sincronía fisiológicos. Múltiples estudios publicados en los últimos años han puesto de manifiesto los efectos perjudiciales de la estimulación convencional, tanto funcionales como estructurales, con las consiguientes morbilidad y mortalidad. De ahí el interés surgido en la búsqueda de sitios alternativos de estimulación que permitan obtener despolarización y contracción miocárdica fisiológicas. En este capítulo se plantea la posibilidad de estimulación auricular en sitios alternativos, con el objetivo fundamental de prevenir las arritmias auriculares. Se revisan, asimismo de forma pormenorizada, las evidencias demostradas hasta el momento acerca de los efectos hemodinámicos y funcionales de la estimulación en tracto de salida de ventrículo derecho, así como su influencia en la duración del QRS y su correlación con la función ventricular. Finalmente, se desarrolla la estimulación permanente del haz de His, con las ventajas que supone la activación ventricular vía sistema específico de conducción (AU)

Since the appearance of the first publication on the transvenous approach to pacemaker implantation in 1959, the apex of the right ventricle has been the conventional site for pacing because it is readily accessible, it provides long-term stability, and the chronic pacing threshold is optimal. Pacing in the right atrial appendage and the ventricular apex enables the heart rate to be stabilized and atrioventricular synchrony to be established, two of the main objectives of extrinsic electrical pacing. However, it does not lead to the establishment of physiologic activation and synchrony patterns. Numerous studies published over the past few years have demonstrated the deleterious effects, both functional and structural, of conventional pacing, and its associated morbidity and mortality. These findings have triggered a search for alternative pacing sites that would enable more physiologic myocardial depolarization and contraction to be achieved. This article discusses the possibility of using alternative atrial pacing sites, with the fundamental aim of preventing atrial arrhythmia. In addition, it also contains a detailed review of the evidence published to date on the hemodynamic and functional effects of right ventricular outflow tract pacing, its influence on the QRS duration, and its correlation with ventricular function. Finally, there is a discussion of permanent His bundle pacing, and the possible advantages associated with ventricular activation via this particular conduction system (AU)