Magnitude, Patterns, and Associated Predictors of Cardiovascular Events in Tetanus: A 2-Year, Single-Center, Ambidirectional Cohort Study Involving 572 Patients.

Background: Cardiovascular events (CEs) remain the leading cause of death in patients with tetanus. We examined the incidence, patterns, and associated predictors of CEs among patients with tetanus in Vietnam.

Methods: An ambidirectional cohort study was conducted on hospitalized adult patients with tetanus at the Hospital for Tropical Diseases between 2019 and 2020. Information on demographics, tetanus disease, CEs and outcomes were collected.

Results: Among all 572 included patients, CEs accounted for 10.8% (95%CI 8.6-13.7%) and included Takotsubo cardiomyopathy (40.3%, 95%CI 29.0-52.8%), arrhythmia (19.4%, 95%CI 11.4-30.9%), sudden cardiac arrest (16.1%, 95%CI 9.0-27.2%), myocardial infarction (11.3%, 95%CI 5.6-21.5%), heart failure (6.5%, 95%CI 2.5-15.4%) and pulmonary embolism (6.5%, 95%CI 2.5-15.4%). CEs occurred from day 5 to 20 of illness. Among 62 CE patients, 21% (95%CI 12.7-32.6%) died and 61.3% (95%CI 48.9-72.4%) developed autonomic nervous system dysfunction (ANSD). Three-fourths (24/32) of patients with Takotsubo cardiomyopathy or myocardial infarction had ANSD. CEs were significantly associated with modified Ablett scores (AOR = 2.42, 95%CI 1.1-5.6, = .04), underlying diseases (AOR = 2.7, 95%CI 1.1-6.8, = .04) and overweight (AOR = 0.18, 95%CI .04-.8, = .02).

Conclusions: CEs are not rare and associated with high mortality. The most common CE is Takotsubo cardiomyopathy. CEs can occur at any stage of illness, with or without ANSD. To prevent mortality, it is pivotal to screen CEs in patients with tetanus, especially those with underlying diseases, high modified Ablett scores, and a normal or low BMI. More studies are needed to fully elucidate the impact of ANSD on the cardiovascular function and the CE associated mortality in tetanus.