[Frequency and detection rate of silent myocardial ischemia by Holter monitoring in patients with stable coronary insufficiency under treatment. Study of 95,725 recorded hours].
OBJECTIVE
To determine in standard living conditions the circadian variation of the symptomatic and silent electrocardiographic ischaemia in patients with chronic stable coronary insufficiency. To evaluate the influence of the past history of the patients on the circadian variations of the symptomatic and silent ischaemic events.


METHODS
The patients included in the study presented with stable angina pectoris and have undergone a 96 hours Ambulatory ECG (AECG) monitoring with a low-weight and compact material which did not modify their daily activities (R-test). The system records the trace that the patient has initiated it himself following the onset of symptoms and makes possible to distinguish between silent and symptomatic ischaemia. The same experienced cardiologist validated all the AECG records.


RESULTS
1,022 patients aged 64.6 +/- 11.0 years suffering of coronary insufficiency from 5.8 +/- 6.0 years have undergone an electrocardiographic record by an R-test for a total duration of 95,725 hours. Of the 1,022 records, 3,258 ischaemic events have been validated: 295 (9.1%) were symptomatic and 2,963 (90.9%) were silent which correspond to a ratio of 1 versus 9 while this ratio is usually described as 1 versus 4. By 26.5% (n = 271) of the patients, ischaemia have been detected and among them more than a half (54.6%, n = 148) were presenting only silent ischaemia. Of these patients who present silent ischaemia, it was recorded during the first 24 hours by only 63.7% of them which is the usual duration of an ambulatory ECG monitoring. This percentage increases to 83.1% after 48 hours and to 94.1% after 72 hours.


CONCLUSIONS
By more than one third (36.3%) of the patients with stable coronary insufficiency, an ambulatory ECG monitoring recorded during only 24 hours is insufficient to detect a silent ischaemia which will happen later. A record duration of 48 hours reduces this risk to 20% of the patients and of 72 hours to less than 5%.
Caussé
C
C
Laboratoires Pierre Fabre cardiovasculaire, Castres.
Allaert
F A
FA
Marcantoni
J P
JP
Wolf
J E
JE
D000203:Activities of Daily Living; D000368:Aged; D002303:Cardiac Output, Low; D002940:Circadian Rhythm; D004562:Electrocardiography; D015716:Electrocardiography, Ambulatory; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis* / Q000000981:diagnostic imaging; D012680:Sensitivity and Specificity; D014463:Ultrasonography