Cardioembolic Ischemic Events More Frequent in Arrhythmogenic Cardiomyopathy

Cardioembolic ischemic events are significantly more frequent in patients with arrhythmogenic cardiomyopathy (ACM) vs the general population, and have a high burden even at younger ages, according to study findings published in the International Journal of Cardiology.

Investigators aimed to assess the occurrence of cardioembolic ischemic events (according to Acute Ischemic Stroke Treatment [TOAST] classification) in patients with ACM and distinguish imaging and clinical predictors of cardioembolic ischemic events. Incidence of atrial arrhythmias, risk for stroke in patients with atrial arrhythmias, and possible utility of CHA₂DS₂-VASc score to identify patients at high risk were secondary points.

The investigators conducted a retrospective, prospective observational, cohort study that enrolled 111 consecutive patients (at least 18 years of age) with ACM at the Città della Salute e della Scienza Hospital, Turin, Italy, from 1982 to October 2022. Atrial arrhythmias were detected with electrocardiography (ECG), Holter monitoring, or implantable cardiac devices. Patient mean age at event was 42±9 years. The investigators excluded patients with ACM family history without phenotypic expression and ACM mimics.

Echocardiographic signs of left ventricular involvement at diagnosis were seen in 39 patients and left atrial dilation in 31 patients. Right ventricular (RV) dilation was found in 69 patients, RV outflow tract dilation in 43 patients, and right atrial dilation in 46 patients. T-wave inversion was the most common ECG finding, occurring in 60 patients.

Across 12.9-year median follow-up, investigators found cardioembolic ischemic events in 11 (10%) patients (hazard ratio, 4.12; incidence rate, 7.9 events/1000 patient-years vs general population incidence rate, 1.9 events/1000 patient-years). Cardioembolic ischemic events were associated with T-wave inversion (P =.03), right ventricular outflow tract dilation (P =.006), female sex (P =.03), and decreased left ventricular ejection fraction (P =.006). Transient ischemic attack accounted for 4 cardioembolic ischemic events and ischemic stroke accounted for 7.

Among 23 patients with atrial arrhythmias (15 atrial fibrillation; 8 atrial flutter), 5 patients experienced cardioembolic ischemic events. CHA₂DS₂-VASc was not helpful for identifying patients at higher risk for cardioembolic ischemic events (P =.098). Patients (specifically women) with stroke had a pre-event score between 0 and 1.

Study limitations include the underpowered sample size and the follow-up was performed at the physician’s discretion.

“In ACM patients, cardioembolic cerebral events are much more common than in [the] general population and present a high burden even at a relatively young age; AAs [atrial arrhythmias] relate to less than half of these events,” the study authors wrote. “In AAs patients, the CHA2DS2-VASc score may not help stratify those requiring oral anticoagulation.”