Abstract 9903: Baseline Left Atrial Abnormality by Electrocardiogram Predicts Incident Stroke in Hypertensive Patients With Electrocardiographic Left Ventricular Hypertrophy
Background: Recent findings in population-based studies suggest that abnormal P-wave terminal force in lead V1 (PTFV1), a marker of left atrial (LA) abnormalities such as fibrosis, dilatation and elevated filling pressures, is associated with incident ischemic stroke, even in the absence of atrial fibrillation (AF). However, whether PTFV1 predicts incident stroke in hypertensive patients during aggressive blood pressure (BP) lowering has not been examined.
Methods: Risk of incident stroke was examined in relation to abnormal PTFV1 on a baseline ECG in 1879 hypertensive patients aged 60 or younger with ECG left ventricular hypertrophy (LVH), no history of AF, in sinus rhythm on their baseline ECG with no incident AF during follow-up, who were randomly assigned to losartan- or atenolol-based treatment. Patients >60 years old were not included because of a highly significant interaction between PTFV1 and age in Cox analyses. Abnormal PTFV1 was defined by the presence of a negative terminal P wave in lead V1 with amplitude x duration ≥4000 V*ms.
Results: During mean follow-up of 4.8±0.9 years, 45 patients (2.4%) experienced a definite stroke. A higher incidence of stroke occurred in those with abnormal than normal baseline PTFV1: incidence rate per 1000 person-years, 7.8, 95% CI, 5.2-11.4 vs 3.4; 95% CI, 2.2-5.2; p=0.004. In univariate Cox models, abnormal PTFV1 was associated with a > 2-fold increased risk of incident stroke (HR 2.31, 95% CI 1.28-4.16, p=0.005). In multivariable Cox regression models that adjusted for other significant predictors of incident stroke in this population (gender, history of stroke or transient ischemic attack, ischemic heart disease or diabetes, baseline creatinine and in-treatment systolic BP), abnormal PTFV1 remained associated with a > 2-fold increased risk of incident stroke (HR, 2.06; 95% CI, 1.14-3.74, p=0.017).
Conclusions: Abnormal PTFV1,a marker of LA abnormality, was strongly associated with incident stroke in hypertensive patients, independent of in-treatment systolic BP and other predictors of incident stroke. This association, in the absence of detectable AF, suggests that an underlying atrial cardiopathy may cause LA thromboembolism and a subsequent stroke without necessarily manifesting with AF.
Author Disclosures: P.M. Okin: Consultant/Advisory Board; Significant; Novartis. H. Kamel: None. S.E. Kjeldsen: Honoraria; Modest; Bayer, Merck, Sharp and Dome, Takeda. Consultant/Advisory Board; Modest; Bayer, Takeda. R.B. Devereux: None.
- © 2015 by American Heart Association, Inc.