Search

Importance: Sudden death is a leading cause of death after acute myocardial infarction (AMI). The Prospective ARNi vs ACE Inhibitor Trial to Determine Superiority in Reducing Heart Failure Events After MI (PARADISE-MI) and Valsartan in Acute Myocardial Infarction (VALIANT) trials enrolled patients with pulmonary congestion and/or left ventricular dysfunction after AMI. Whether the prognosis in such patients has changed over time has not been examined., Objective: To compare the rate of sudden death/resuscitated cardiac arrest (RCA) after AMI in the PARADISE-MI and VALIANT trials., Design, Setting, and Participants: This was a secondary analysis of multicenter randomized clinical trials enrolling patients after AMI. In the primary analysis, the VALIANT cohort was restricted to patients with "PARADISE-MI-like" characteristics (eg, at least 1 augmenting risk factor and no history of heart failure). The baseline characteristics of people in both trials were compared. The VALIANT trial enrolled from December 1998 to June 2001, and the PARADISE-MI trial enrolled between December 2016, and March 2020. The median follow-up in the VALIANT and PARADISE-MI trials was 24.7 and 22 months, respectively. People with AMI, complicated by pulmonary congestion and/or left ventricular dysfunction, were included in the analysis., Exposure: Sudden death after AMI., Results: A total of 5661 patients were included in the PARADISE-MI cohort (mean [SD] age, 63.7 [11.5] years; 4298 male [75.9%]), 9617 were included in the VALIANT (PARADISE-MI-like) cohort (mean [SD] age, 66.1 [11.5] years; 6504 male [67.6%]), and 14 703 patients were included in the VALIANT (total) cohort (mean [SD] age, 64.8 [11.8] years; 10 133 male [68.9%]). In the PARADISE-MI-like cohort of the VALIANT trial, 707 of 9617 participants (7.4%) experienced sudden death/RCA. A total of 148 of 5661 people (2.6%) in the PARADISE-MI trial experienced sudden death/RCA. Sudden death rates were highest in the first month after infarction in both trials: 19.3 (95% CI, 16.4-22.6) per 100 person-years in the VALIANT trial and 9.5 (95% CI, 7.0-12.7) per 100 person-years in the PARADISE-MI trial, and these rates declined steadily thereafter. Compared with the VALIANT cohort, people in the PARADISE-MI trial were more often treated with percutaneous coronary intervention for their qualifying AMI and received a β-blocker, statin, and mineralocorticoid receptor antagonist more frequently., Conclusions and Relevance: After AMI, the risk of sudden death/RCA was highest in the first month, declining rapidly thereafter. Results revealed that compared with counterparts from 20 years ago, the rate of sudden death/RCA in patients with a reduced left ventricular ejection fraction and/or pulmonary congestion was 2- to 3-fold lower in people receiving contemporary management. Interventions to further protect people in the highest risk first month after infarction are needed., Trial Registration: ClinicalTrials.gov Identifier: NCT02924727.

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 cardioverter-defibrillator. 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; P=0.04)., 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.

Background: The frequency of sudden unexpected death is highest in the early post-myocardial infarction (MI) period; nevertheless, 2 recent trials showed no improvement in mortality with early placement of an implantable cardioverter-defibrillator after MI., Methods and Results: To better understand the pathophysiological events that lead to sudden death after MI, we assessed autopsy records in a series of cases classified as sudden death events in patients from the VALsartan In Acute myocardial infarctioN Trial (VALIANT). Autopsy records were available in 398 cases (14% of deaths). We determined that 105 patients had clinical circumstances consistent with sudden death. On the basis of the autopsy findings, we assessed the probable cause of sudden death and evaluated how these causes varied with time after MI. Of 105 deaths considered sudden on clinical grounds, autopsy suggested the following causes: 3 index MIs in the first 7 days (2.9%); 28 recurrent MIs (26.6%); 13 cardiac ruptures (12.4%); 4 pump failures (3.8%); 2 other cardiovascular causes (stroke or pulmonary embolism; 1.9%); and 1 noncardiovascular cause (1%). Fifty-four cases (51.4%) had no acute specific autopsy evidence other than the index MI and were thus presumed arrhythmic. The percentage of sudden death due to recurrent MI or rupture was highest in the first month after the index MI. By contrast, after 3 months, the percentage of presumed arrhythmic death was higher than recurrent MI or rupture (chi(2)=23.3, P<0.0001)., Conclusions: Recurrent MI or cardiac rupture accounts for a high proportion of sudden death in the early period after acute MI, whereas arrhythmic death may be more likely subsequently. These findings may help explain the lack of benefit of early implantable cardioverter-defibrillator therapy.

Background: The risk of sudden death from cardiac causes is increased among survivors of acute myocardial infarction with reduced left ventricular systolic function. We assessed the risk and time course of sudden death in high-risk patients after myocardial infarction., Methods: We studied 14,609 patients with left ventricular dysfunction, heart failure, or both after myocardial infarction to assess the incidence and timing of sudden unexpected death or cardiac arrest with resuscitation in relation to the left ventricular ejection fraction., Results: Of 14,609 patients, 1067 (7 percent) had an event a median of 180 days after myocardial infarction: 903 died suddenly, and 164 were resuscitated after cardiac arrest. The risk was highest in the first 30 days after myocardial infarction--1.4 percent per month (95 percent confidence interval, 1.2 to 1.6 percent)--and decreased to 0.14 percent per month (95 percent confidence interval, 0.11 to 0.18 percent) after 2 years. Patients with a left ventricular ejection fraction of 30 percent or less were at highest risk in this early period (rate, 2.3 percent per month; 95 percent confidence interval, 1.8 to 2.8 percent). Nineteen percent of all sudden deaths or episodes of cardiac arrest with resuscitation occurred within the first 30 days after myocardial infarction, and 83 percent of all patients who died suddenly did so in the first 30 days after hospital discharge. Each decrease of 5 percentage points in the left ventricular ejection fraction was associated with a 21 percent adjusted increase in the risk of sudden death or cardiac arrest with resuscitation in the first 30 days., Conclusions: The risk of sudden death is highest in the first 30 days after myocardial infarction among patients with left ventricular dysfunction, heart failure, or both. Thus, earlier implementation of strategies for preventing sudden death may be warranted in selected patients., (Copyright 2005 Massachusetts Medical Society.)

Objectives: This study sought to delineate salvage-dependent from salvage-independent coronary reperfusion in acute myocardial infarction and the effects on spontaneously occurring arrhythmias and arrhythmic death in rats., Background: Reperfusion of the infarct-related artery might increase electrical stability independently of salvage of ischemic myocardium., Methods: In 98 conscious rats the electrocardiogram was monitored by telemetry for 48 h after MI, and all episodes of ventricular tachycardia (VT) and ventricular fibrillation (VF) were analyzed. Reperfusion at 45 min (RP45) (n = 15), 90 min (RP90) (n = 18) and 180 min (RP180) (n = 30) min was compared with permanent coronary artery occlusion (CAO) (n = 35) with respect to the post-reperfusion periods., Results: RP45, RP90 and RP180 reduced the incidence of VT by 93%, 98% and 88% and VF by 89%, 97% and 92%, respectively (all p < 0.01 vs. CAO). The all-cause mortality rate was reduced from 47% (CAO) to 8% (RP45, p < 0.05) and 0% (RP90, p < 0.01); after RP180 it was 17% (CAO 42%, p = 0.08). All reperfusion regimens reduced arrhythmic deaths: 47% to 8% (RP45, p < 0.05), 47% to 0% (RP90, p < 0.01) and 42% to 8% (RP180, p < 0.05). Infarct size was identical to that during CAO (49 +/- 10% [mean +/- SD]) and RP180 (49 +/- 10%), whereas preferentially epicardial salvage occurred at RP45 (36 +/- 8%, p < 0.001) and RP90 (38 < 10%, p < 0.001)., Conclusions: Early and late reperfusion reduce the incidence and duration of VT and VF in conscious rats with acute MI. Thereby, arrhythmia-related mortality is improved through the prevention of fatal VF episodes. Thus, reperfusion increases the electrical stability of the heart independently of myocyte salvage, as proposed by the open artery hypothesis.