title: Characteristics of patients with nonfatal cardiac arrest 3 to 180 days after acute myocardial infarction.
abstract: Patients who survive a tachyarrhythmic cardiac arrest in the first 6 months after acute myocardial infarction (AMI) are at risk for recurrent arrests, but the magnitude, timing and characteristics of this phenomenon are unknown. This study characterizes the nature of recurrent tachyarrhythmic cardiac arrests in the absence of reversible factors or new myocardial necrosis in patients between 3 and 180 days after AMI. We retrospectively assessed 28 patients (mean age 61 +/- 12 years) who survived an initial cardiac arrest a median of 10 days after AMI. Mean left ventricular ejection fraction was 36 +/- 9%. Fourteen patients (50%) had at least 1 recurrence of cardiac arrest, and 10 had > 2 arrests. Almost all (92%) recurrent cardiac arrests occurred within 5 days of the preceding arrest, and the high-risk periods were similar after the first, second or third cardiac arrest. Very fast ventricular tachycardia (mean cycle length 212 +/- 30 ms) was the documented responsible arrhythmia in 44 of 51 cardiac arrests. The morphology was either polymorphic, monomorphic or sinusoidal. No clinical or laboratory values could be found that predicted whether a patient would have a recurrent arrest. Nineteen patients (68%) survived to leave the hospital and have been followed for up to 96 months. For these, actuarial 5-year overall survival was 76% and actuarial 5-year arrhythmia-free probability was 80%. Thus, patients who survive a cardiac arrest in the first 6 months after AMI are at high risk of recurrent cardiac arrest for a further 5 days, and the arrests are due to characteristically fast ventricular tachycardias.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Cardiovascular Research Group, University of Calgary, Alberta, Canada.
authors.forename: R S
authors.initials: RS
authors.lastname: Sheldon
authors.forename: D G
authors.initials: DG
authors.lastname: Wyse
authors.forename: L B
authors.initials: LB
authors.lastname: Mitchell
authors.forename: A M
authors.initials: AM
authors.lastname: Gillis
authors.forename: K M
authors.initials: KM
authors.lastname: Kavanagh
authors.forename: H J
authors.initials: HJ
authors.lastname: Duff
mesh_terms: D000206:Actuarial Analysis; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002304:Cardiac Pacing, Artificial; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006323:Heart Arrest / Q000209:etiology / Q000401:mortality / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications*; D012008:Recurrence; D012189:Retrospective Studies; D013318:Stroke Volume; D016019:Survival Analysis; D017180:Tachycardia, Ventricular / Q000150:complications / Q000628:therapy