Background The clinical impact of the influenza vaccination on cardiovascular outcomes in people with established cardiovascular disease (CVD) is still debated. Aim The aim of this meta-analysis was to estimate the effect of influenza vaccination on cardiovascular and cerebrovascular outcomes among patients with established CVD. Methods We systematically searched all electronic databases from inception until 15 April 2022. Primary clinical outcomes were all-cause mortality (ACM), and major adverse clinical events (MACE). Secondary endpoints were heart failure, myocardial infarction, CV mortality, and stroke. Results Eighteen articles (five randomized trials and thirteen observational studies), with a total of 22,532,165 patients were included in the analysis. There were 217,072 participants included in the high cardiovascular risk or established CVD population (vaccinated n = 111,073 and unvaccinated n = 105,999). The mean age of the patients was 68 years old, without any difference between groups (69 vs 71) years. At mean follow-up of 1.5 years, vaccinated group was associated with lower risk for all-cause mortality [HR, 0.71(95%CI, 0.63-0.80), p < 0.001], MACE [HR, 0.83(95%CI:0.72-0.96), p = 0.01], CV mortality [HR, 0.78(95%CI:0.68-0.90), p < 0.001] and myocardial infarction [HR, 0.82(95%CI:0.74-0.92), p < 0.001] compared to unvaccinated group. While incidence of stroke [HR, 1.03 (95%CI, 0.92-1.06), p = 0.61] and heart failure [HR, 0.74 (95%CI, 0.51-1.08), p = 0.12] did not differ between the two groups. Conclusion Influenza vaccination reduced major adverse clinical events, all-cause mortality, CV mortality and myocardial infarction. These highlighted the importance of influenza vaccination in established CVD or high cardiovascular risk.

To date, there were limited studies available on myocardial infarction (MI), and consequently, the outcomes of patients with type 1 myocardial infarction (T1MI) compared to type 2 myocardial infarction (T2MI) remained inconclusive. We aimed to compare the outcomes of T1MI and T2MI patients in terms of mortality and adverse cardiovascular outcomes. We performed a systematic literature search on PubMed, Embase, and Scopus for relevant articles from inception until March 20, 2022. 341,049 patients had T1MI, while the remaining 67,537 patients had T2MI. Mean age was similar between both groups (T1MI: 67.3 years, T2MI: 71.03 years), while the proportion of females was lower in T1MI (37.81% vs 47.15%). Our analysis revealed that patients with T1MI had significantly lower odds of all-cause mortality (OR 0.45, 95% CI 0.36–0.56, p < 0.001), in-hospital mortality (OR 0.63, 95% CI 0.46–0.86, p < 0.001), 1-year mortality (OR 0.35, 95% CI 0.25–0.47, p < 0.001), and major adverse cardiovascular events (MACE) (OR 0.59, 95% CI 0.39–0.91, p = 0.02). There was no significant difference in terms of 30-day mortality (OR 0.58, 95% CI 0.25–1.36, p = 0.21), cardiovascular mortality (OR 0.95, 95% CI 0.68–1.32, p = 0.74), all-cause readmission (OR 0.84, 95% CI 0.62–1.14, p = 0.26), and readmission due to MI (OR 1.22, 95% CI 0.66–2.27, p = 0.53) between both groups. Patients with T1MI had favorable outcomes in terms of mortality and MACE compared to that of T2MI patients. Further studies should aim at determining the optimal management strategy for these high-risk patients for better patient outcomes.

No abstract

No abstract

No abstract