Silent myocardial ischaemia in treated hypertensives with and without left ventricular hypertrophy.

BACKGROUND

Silent ischaemia has been reported to be associated with an increased risk of myocardial infarction and sudden death in a wide range of patient groups. The aim of this study was to examine the prevalence of silent ischaemia in hypertensive patients with and without left ventricular hypertrophy (LVH).

METHODS

Twenty hypertensive patients participating in the Anglo-Scandinavian Cardiac Outcomes Trial with echocardiographic LVH (11 males, nine females), and 20 age, sex, blood pressure, and drug treatment-matched hypertensive patients without LVH underwent 24-h combined ambulatory blood pressure and electrocardiographic (ECG) monitoring. Ischaemic events were defined by the 'rule of 3 x 1'-asymptomatic ST-depression >/= 1 mm (0.1 mV), lasting at least 1 min, and with a duration of at least 1 min between two events.

RESULTS

Thirteen patients with LVH had ischaemic events, whilst only four without LVH demonstrated ischaemia. Median numbers of events (seven versus zero; P < 0.01) and median total ischaemic area (0.25 versus 0 mV*min/day; P < 0.01) were significantly increased amongst hypertensive patients with LVH by comparison to those without LVH.

CONCLUSION

Despite similar levels of established risk factors for atherosclerotic coronary artery disease, the prevalence of silent ischaemia was markedly increased amongst hypertensive patients with LVH by comparison to those with normal left ventricular dimensions. Ambulatory ECG monitoring may have a use in the identification of those at greatest risk of cardiovascular complications and sudden death, amongst hypertensive patients with persistent cardiac hypertrophy despite anti-hypertensive therapy.