Association of electrocardiographic left ventricular hypertrophy with incident cardiovascular disease in Japanese older hypertensive patients

BACKGROUND: Our aim was to assess whether electrocardiographic left ventricular hypertrophy (ECG-LVH) is associated with a higher risk of cardiovascular disease (CVD) events, independent of 24-hour blood pressure (BP) and circulating levels of norepinephrine and hemostatic factors.

METHODS: In 514 older hypertensive patients (mean age 72.3 years; 37% men), we assessed ambulatory BP values, circulating levels of norepinephrine and hemostatic factors (plasma fibrinogen, prothrombin fragment 1+2 (F1+2), von Willebrand factor (vWF), and plasminogen activator inhibitor-1 (PAI-1)), and the presence or absence of ECG-LVH (Sokolow-Lyon voltage ≥ 3.5 mV). The incidence of CVD events (i.e., myocardial infarction and stroke) was prospectively ascertained.

RESULTS: During an average 41 months of follow-up (1,751 person-years), 43 stroke and 3 myocardial infarction events occurred. At baseline, patients with ECG-LVH had higher mean 24-hour BP (148.8/83.8mm Hg vs. 135.7/77.2mm Hg) and circulating norepinephrine levels (404.6 pg/ml vs. 336.3 pg/ml) compared to those without ECG-LVH; the differences remained unchanged after adjustment for age, gender, smoking status, presence of diabetes, and antihypertensive medication uses at follow-up time (all P < 0.01). Cox proportional hazards models suggested that the hazard ratio (HR; 95% confidence interval (CI)) of CVD events for those with ECG-LVH was 4.4 (2.3-8.2), and the association between ECG-LVH and incident CVD events remained significant after adjustment for high 24-hour BP (≥130/80mm Hg), nocturnal SBP, circulating norepinephrine and fibrinogen levels (HRs, 3.5-4.2, all P < 0.001).

CONCLUSIONS: In older hypertensive patients, ECG-LVH was associated with a higher risk of CVD events, independent of ambulatory BP parameters and circulating norepinephrine and fibrinogen levels.