The role of infarction-associated pericarditis on the occurrence of atrial fibrillation.
OBJECTIVE
Transient atrial fibrillation is a relatively common arrhythmia in the early phase of acute Q-wave myocardial infarction. However, the role of infarction-associated pericarditis on the genesis of atrial fibrillation is controversial. This study was designed to examine the relative importance of infarction-associated pericarditis among other clinical variables on the genesis of transient atrial fibrillation in patients with acute myocardial infarction.


RESULTS
Three hundred and ninety-eight patients with acute Q-wave myocardial infarction were examined carefully by means of auscultation, ECG, two-dimensional echocardiography and haemodynamic measurements. The diagnosis of pericarditis was made on the basis of pericardial rub detected during the first 3 days after admission. At least 0.5 mm of PQ-segment depression from a TP segment lasting more than 24 h in both limb and precordial leads was considered diagnostic of PQ-segment depression. Atrial fibrillation was present in 76 patients (19%). Sixteen (42%) of 38 patients with PQ-segment depression had atrial fibrillation, whereas 23 (30%) of 77 patients with pericardial rub had atrial fibrillation. Based on ten clinical variables, multivariate analysis was performed to determine the important variables related to the occurrence of atrial fibrillation. PQ-segment depression (chi-square = 4.10, P < 0.05) was selected with age (chi-square = 10.52, P < 0.005), the number of left ventricular segments with advanced asynergy (chi-square = 7.73, P < 0.01) and pericardial effusion (chi-square = 7.95, P < 0.005) as important factors related to atrial fibrillation. Patients with PQ-segment depression had a significantly higher pulmonary capillary wedge pressure than those without it.


CONCLUSIONS
Among patients with infarction-associated pericarditis, those with PQ-segment depression represent atrial involvement associated with extensive myocardial damage and hence, PQ-segment depression is one of the clinical signs related to the occurrence of atrial fibrillation in acute Q-wave myocardial infarction.
Nagahama
Y
Y
Second Department of Internal Medicine, Kansai Medical University, Osaka, Japan.
Sugiura
T
T
Takehana
K
K
Hatada
K
K
Inada
M
M
Iwasaka
T
T
D000368:Aged; D001281:Atrial Fibrillation / Q000453:epidemiology* / Q000209:etiology* / Q000503:physiopathology; D004452:Echocardiography; D004562:Electrocardiography; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications* / Q000503:physiopathology / Q000628:therapy; D010493:Pericarditis / Q000150:complications* / Q000209:etiology*; D015912:Thrombolytic Therapy