Praveen Hariharan, MD
Over the last two decades, an increasing body of evidence has recognized various cardiovascular complications following ischemic stroke collectively known as the stroke-heart syndrome. Ischemic stroke can cause impaired autonomic cardiac reflexes, repolarization abnormalities, myocardial injury and cardiomyopathy resulting in myocardial infarction, cardiac arrhythmias including atrial fibrillation, new-onset or exacerbation of heart failure, recurrent stroke, poor functional outcomes, and increased mortality. Many studies have explored the short-term consequences, but there is a paucity of data on long-term clinical outcomes.
In this study, the authors have utilized retrospective observational data obtained from a global federated health research network called TriNetX. Patients with an incident acute ischemic stroke from 2002-2021 with at least 5 years follow up were included. Ischemic stroke patients with newly diagnosed cardiovascular complications within 4 weeks post-stroke were 1:1 propensity score-matched (for baseline demographics and comorbidities) with ischemic stroke patients without cardiovascular complications for comparison of 5-year MACE (major adverse cardiovascular events) outcomes.
A total of 365,383 patients were identified from 53 healthcare organizations: 11.1% developed ACS, 8.8% atrial fibrillation/flutter, 6.4% heart failure, 1.2% severe ventricular arrhythmia, and 0.1% Takotsubo syndrome within 4 weeks of stroke. On comparison with stroke patients without cardiovascular complications, stroke patients with cardiovascular complications had significantly higher risk of 5-year mortality if they developed ACS (OR 1.49, 95% CI 1.44-1.54), atrial fibrillation/flutter (OR 1.45, 95% CI 1.4-1.5), heart failure (OR 1.83, 95% CI 1.76-1.91), severe ventricular arrhythmia (OR 2.08, 95% CI 1.9-2.29), and Takotsubo syndrome (OR 1.89, 95% CI 1.29-2.77). Five-year hospitalization rates were also significantly higher in patients who developed ACS (OR 1.15, 95% CI 1.12-1.18), atrial fibrillation/flutter (OR 1.3, 95% CI 1.26-1.34), heart failure (OR1.44, 95% CI 1.39-1.49), and severe ventricular arrhythmia (OR 1.21, 95% CI 1.11-1.31). Only patients with atrial fibrillation had higher odds of recurrent stroke at 5 years (OR 1.1, 95% CI 1.07-1.14).
In conclusion, cardiovascular complications following stroke were associated with substantially worse long-term prognosis at 5 years. It is interesting to note that 5-year MACE outcomes were higher than noted in previous literature despite potentially missing cases that occurred outside of the TriNetX network. Other limitations include unavailability of data on severity/location of stroke and the inability to determine the cause-and-effect relationship between cardiovascular complications and ischemic stroke in this retrospective database.
The study underlines the importance of prospective studies for better risk prediction and to potentially understand the utility of tailored therapeutic interventions, including cardiac rehabilitation, in patients with stroke-heart syndrome.
