RESUMO
Background: Postoperative atrial fibrillation (AF) has a complex etiology, and beta-blockers are commonly recommended for its pharmacological prevention. This study aims to assess the impact of beta-blocker therapy on postoperative AF occurrence in patients undergoing aortic valve replacement, mitral valve replacement, surgical revascularization of the myocardium, or a combination of these procedures. Methods: The study encompassed 472 patients who received aortic valve replacement, mitral valve replacement, surgical revascularization, or their combination. We evaluated the efficacy of preoperative and one-month postoperative beta-blocker administration in preventing postoperative AF, and the associated risk factors involved in the development of postoperative AF. Results: Of the total patient population, 36% experienced postoperative AF. Our study demonstrated a significant reduction in postoperative AF incidence among patients receiving beta-blocker treatment (all p-values < 0.05). Additionally, one-month post-surgery, beta-blocker treatment exerted a protective effect by maintaining the sinus rhythm (p = 0.0001). Regarding the risk factors involved in the development of postoperative AF, both age and left atrium (LA) sizeassessed pre-and postoperatively-were positively correlated with the occurrence of postoperative AF (p = 0.006). No relationship was found between leukocyte counts and AF incidence. Notably, C-reactive protein (CRP) levels were significantly elevated on the fifth postoperative day in patients with AF (p < 0.007). The duration of ischemia was significantly longer in patients with AF (p = 0.009). Conclusions: This study establishes the efficacy of perioperative beta-blocker treatment in mitigating postoperative AF. One month post-surgery, most patients under beta-blocker therapy maintained sinus rhythm, suggesting a potential long-term protective effect of beta-blockers against late-onset AF.
RESUMO
BACKGROUND: Development of valvular substitutes meeting the performance criteria for surgical correction of congenital heart malformations is a major research challenge. The sheep is probably the most widely used animal model in heart valves regenerative medicine. Although the standard cardiopulmonary bypass (CPB) technique and various anesthetic and surgical protocols are reported to be feasible and safe, they are associated with significant morbidity and mortality rates. The premise of this paper is that the surgical technique itself, especially the perioperative animal care and management protocol, is essential for successful outcomes and survival. METHODS: Ten juvenile and adult female sheep aged 7.8-37.5 months and weighing 32.0-58.0 kg underwent orthotopic implantation of tissue-engineered pulmonary valve conduits on beating heart under normothermic CPB. The animals were followed-up for 6 months before scheduled euthanasia. RESULTS: Based on our observations, we established a guide for perioperative care, follow-up, and treatment containing information regarding the appropriate clinical, biological, and ultrasound examinations and recommendations for feasible and safe anesthetic, surgical, and euthanasia protocols. Specific recommendations were also included for perioperative care of juvenile versus adult sheep. CONCLUSION: The described surgical technique was feasible, with a low mortality rate and minimal surgical complications. The proposed anesthetic protocol was safe and effective, ensuring both adequate sedation and analgesia as well as rapid recovery from anesthesia without significant complications. The established guide for postoperative care, follow-up and treatment in sheep after open-heart surgery may help other research teams working in the field of heart valves tissue regeneration.