Prognostic impact of left bundle-branch block in the early stable phase after acute myocardial infarction.
BACKGROUND
Diagnostic marker parameters are needed to enable timely identification of high risk patients after acute myocardial infarction (MI). We assessed risk factors for death and sudden death in stable revascularized patients undergoing guideline-based therapy during an in-patient rehabilitation program more than 3 weeks after acute myocardial infarction.


METHODS
During an in-patient rehabilitation program, 939 patients with a recent myocardial infarction were prospectively included. Besides demographic and clinical data, ejection fraction (EF), Holter ECG, standard 12-lead electrocardiogram (ECG) and baseline laboratory values were determined. Patients were followed up for 18 months.


RESULTS
Among multiple variables, left bundle-branch block (LBBB) was the most significant parameter affecting the outcome (combination endpoint of death, resuscitation or ventricular tachycardia (VT)), hazard ratio 7.74 (3.2-18.7, P<0.0001). 42% of the 24 patients with LBBB but only 11.5% of the 62 patients with a left ventricular EF </=30% died during follow-up (P<0.001).


CONCLUSIONS
LBBB observed during a rehabilitation program following an acute MI indicates a grave prognosis with a high mortality rate (mainly caused by sudden death). Future studies are required to establish whether this simple marker characterizes a group of patients that will profit from preventive defibrillator implantation and/or biventricular pacing.
Dissmann
Rüdiger
R
Medizinische Klinik II (Kardiologie/Nephrologie) Klinikum Bremerhaven Reinkenheide, Postbrookstr. 103, D-27574 Bremerhaven, Germany.
Kamke
Wolfram
W
Reibis
Rona
R
Herbstleb
Joachim
J
Wegscheider
Karl
K
Völler
Heinz
H
D000368:Aged; D002037:Bundle-Branch Block / Q000175:diagnosis* / Q000401:mortality*; D016757:Death, Sudden, Cardiac / Q000453:epidemiology; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000401:mortality* / Q000534:rehabilitation; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012044:Regression Analysis; D012307:Risk Factors