Chronic Myocardial Injury and Risk for Stroke

Chronic myocardial injury, defined as persistent troponin levels >99th percentile values when measured with high-sensitivity assays (hs-cTn), is common. The association between chronic myocardial injury and stroke is unknown. This study aimed to investigate the association between chronic myocardial injury and stroke.

From 2011 to 2014, we included patients with chest pain and high-sensitivity cardiac troponin T levels measured concurrently but without acute conditions associated with elevated high-sensitivity cardiac troponin T levels. Cox regression was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) for stroke in patients with stable high-sensitivity cardiac troponin T levels of 5-9, 10-14, 15-29, 30-49, and ≥50 ng/L, using <5 ng/L as reference group. Categories >14 ng/L were defined as chronic myocardial injury.

A total of 19,460 patients were included, among whom 1528 (7.9%) had chronic myocardial injury. During a mean follow-up of 2.1 years, there were 244 (1.2%) strokes. With increasing high-sensitivity cardiac troponin T levels yearly stroke rates increased from 0.24% to 4.0%. Adjusted hazard ratios with 95% confidence intervals for stroke were 1.83 (1.27-2.64) in patients with high-sensitivity cardiac troponin T levels of 5-9 ng/L, increasing to 1.95 (1.21-3.14), 3.38 (1.80-6.35), and 4.32 (1.89-9.91) in patients with high-sensitivity cardiac troponin T levels of 15-29, 30-49, and ≥50 ng/L, respectively.

Patients with chronic myocardial injury have up to a 4-fold increased risk of stroke compared with patients with high-sensitivity cardiac troponin T levels <5 ng/L. Our findings indicate that patients with any detectable high-sensitivity cardiac troponin T level, in particular those with chronic myocardial injury, have an increased risk of stroke and require further attention.