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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
1 Pt 1
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| pubmed:dateCreated |
1989-3-17
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| pubmed:abstractText |
We performed a prospective study of the high-frequency components of the terminal portion of the QRS complex in 220 patients who survived acute myocardial infarction. Signal-averaged electrocardiograms (SA-ECGs) were performed before hospital discharge (16 +/- 6 days) and then serially at regular intervals over the following year. SA-ECGs were processed using a 40 Hz high-pass bidirectional filter. Duration of "filtered" QRS (D-normal value less than 120 ms), duration of the low-amplitude signals (D40 - n.v. less than 39 ms) and last 40 ms voltage of the QRS complex (V40 - n.v. greater than 20 microV) were measured. Late potentials (LPs) were defined as the presence of two or more abnormal values. In addition, 24-hour Holter monitoring was performed in 208 patients and left ventricular ejection fraction (LVEF) was determined by scintigraphy in 111. Sixty-two patients (group 1) had LPs, 158 had normal SA-ECGs (group 2). Spontaneous normalization of SA-ECGs occurred in 20% of patients after 6 months, although the mean values of D, D40 and V40 did not change significantly and the reproducibility was very good for all the indexes during all the follow-up controls. Three patients had sudden death and three presented again with spontaneous, sustained ventricular tachycardia. Five of 62 (8%) group 1 patients had an arrhythmic event compared with one of 158 patients (0.6%) in group 2. The sensitivity of SA-ECGs as a predictor of arrhythmic events was 83% with a specificity of 73%. Patients with subsequent arrhythmic events had longer filtered QRS (133 +/- 19 vs 104 +/- 16 ms; P less than 0.001), longer duration of the low-amplitude signals (54 +/- 15 vs 33 +/- 14 ms; P less than 0.01), and lower voltages in the last 40 ms of the filtered QRS (11 +/- 3 vs 36 +/- 25 microV; P less than 0.02) and, moreover, higher peak CK values and lower LVEF than those without such events. In conclusion, SA-ECGs provide important prognostic information in identifying patients at risk of arrhythmic events after myocardial infarction although dynamic changes of LPs are observed during the first year after myocardial infarction.
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| pubmed:language |
eng
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| pubmed:journal | |
| pubmed:citationSubset |
IM
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| pubmed:status |
MEDLINE
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| pubmed:month |
Jan
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| pubmed:issn |
0147-8389
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| pubmed:author | |
| pubmed:issnType |
Print
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| pubmed:volume |
12
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| pubmed:owner |
NLM
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| pubmed:authorsComplete |
Y
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| pubmed:pagination |
41-51
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| pubmed:dateRevised |
2007-11-15
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| pubmed:meshHeading |
pubmed-meshheading:2464810-Arrhythmias, Cardiac,
pubmed-meshheading:2464810-Death, Sudden,
pubmed-meshheading:2464810-Electrocardiography,
pubmed-meshheading:2464810-Female,
pubmed-meshheading:2464810-Follow-Up Studies,
pubmed-meshheading:2464810-Humans,
pubmed-meshheading:2464810-Male,
pubmed-meshheading:2464810-Middle Aged,
pubmed-meshheading:2464810-Monitoring, Physiologic,
pubmed-meshheading:2464810-Myocardial Infarction,
pubmed-meshheading:2464810-Prognosis,
pubmed-meshheading:2464810-Prospective Studies,
pubmed-meshheading:2464810-Risk Factors,
pubmed-meshheading:2464810-Signal Processing, Computer-Assisted,
pubmed-meshheading:2464810-Stroke Volume
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| pubmed:year |
1989
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| pubmed:articleTitle |
Prognostic significance and evolution of late ventricular potentials in the first year after myocardial infarction: a prospective study.
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| pubmed:affiliation |
Divisione di Cardiologia, Ospedale San Paolo, Milano, Italy.
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| pubmed:publicationType |
Journal Article
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