Cardiac Contractility Modulation in Patients with Advanced Heart Failure: A Comprehensive Review of Literature.

Heart failure is a significant cause of morbidity and mortality worldwide. Despite advancements in guideline-directed medical therapy and improvements in device-based therapies, patients with advanced heart failure have high rates of mortality regardless of ejection fraction. For patients with reduced ejection fraction who meet criteria, cardiac resynchronization therapy or implantable cardiac defibrillators are options available to improve outcomes. However, not all heart failure patients meet those criteria. Cardiac contractility modulation is an innovative therapy that serves to improve functional outcomes and quality of life, while also modifying pathologic gene expression and preventing further remodeling. In this article, we aim to discuss the major clinical trials investigating cardiac contractility modulation as a suitable therapy for patients with advanced heart failure.

Syncope With Sinus Arrest Following a Single Dose of a COVID-19 Vaccine.

Vaccines against the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) are of paramount importance in combating the current coronavirus disease 2019 (COVID-19) pandemic. Syncopal episodes following routine vaccinations are well-reported; however, only a few cases of syncope following SARS-CoV-2 vaccines exist in the literature. This is a case report of a 21-year-old female patient who developed recurrent syncopal attacks over three months that started one day after receiving the first dose of the Pfizer-BioNTech COVID-19 vaccine (Pfizer, New York City; BioNTech, Mainz, Germany). Holter monitoring during successive episodes showed progressive bradycardia followed by a prolonged sinus arrest. The patient eventually required pacemaker placement that resulted in the total resolution of her symptoms. Further studies are required to investigate a possible correlation and the mechanisms involved.