Circumstances and Outcomes of Sudden Unexpected Death in Patients With High-Risk Myocardial Infarction

Abstract

Background-Sudden death (SD) is a frequent catastrophic complication in patients after myocardial infarction.Circumstances of SD may affect strategies for prevention. Methods and Results-We reviewed source documentation for 1067 patients who had SD in the Valsartan in Acute Myocardial Infarction Trial (VALIANT) trial. We determined the circumstances of these events and assessed long-term mortality in patients who were resuscitated. Location of the SD event was available in 978 of 1067 patients, with 226 events occurring within the first 40 days. Although SD was more likely to occur at home (645 of 978, 66%) than in hospital (204 of 978, 21%), the proportion of in-hospital events was higher early on (99 of 226, 44%). Home events were less likely to be witnessed regardless of time frame. Preceding activity was known for 42% of patients with home arrest; of these, 52% were determined to be asleep at time of event, and these deaths were more likely to be unwitnessed. A majority of patients for whom initial ECG rhythm was reported had ventricular tachycardia/ventricular fibrillation (189 of 283, 67%). Of the 155 patients successfully resuscitated, 24% subsequently received an implantable cardioverterdefibrillator. Nineteen percent of those who received an implantable cardioverter-defibrillator subsequently died compared with 49% of patients who did not receive an implantable cardioverter-defibrillator (hazard ratio, 0.36; 95% confidence interval, 0.14 to 0.93; Pϭ0.04). Conclusions-A high proportion of SD events after high-risk myocardial infarction occurred at home, but in-hospital events were more common early on. Patients who were asleep were more likely to have unwitnessed arrests. Alternative strategies for the prevention of SD in patients who are not candidates for implantable cardioverter-defibrillator will need to take into account the circumstances of SD events. (Circulation. 2011;123:2674-2680.)

Sudden Cardiac Death in Heart Failure

“…3 More than 80% of deaths in patients with HF have cardiovascular causes, with most being either sudden cardiac deaths (SCDs) or deaths caused by progressive pump failure. 4 In general, SCD events are defined as unexpected deaths from cardiovascular causes that are preceded by a witnessed collapse, occur within 1 hour of an acute change in clinical condition, or occur not more than 24 hours after the deceased individuals were known to be in their usual state of health. 5 It is estimated that 350,000 to 380,000 SCD cases occur every year in the adult population in the United States, and that most of these individuals have preexisting heart disease.…”

Causes of sudden unexpected death of adult hospital patients

“…11 More prophylactic antiarrhythmic medication and automatic implanted cardiac defibrillators might also be helpful. 12 Some UPMC intensivists believe that the sort of fatal arrhythmias seen in this study are caused by hypoxemia, which suggests that more pulse oximetry oxygen saturation monitoring might allow preventative intervention. 13 More frequent and possibly automated monitoring of vital signs might provide early warning of hemorrhage or pulmonary embolization.…”

HRS/ACC/AHA Expert Consensus Statement on the Use of Implantable Cardioverter-Defibrillator Therapy in Patients Who Are Not Included or Not Well Represented in Clinical Trials

“…20 In a subsequent analysis of the 164 patients who had successful resuscitation after sudden death in VALIANT, 75 had cardiac arrest within the first 40 days after myocardial infarction. 31 Investigators felt that ICD implantation would have been beneficial in 16 of these patients, with a median time of 11 days between cardiac arrest and ICD implant. ICD implantation was associated with a nonsignificant decrease in mortality (HR: 0.44; 95% CI: 0.10-2.01; P=.…”