Evolution of Left Ventricular Ejection Fraction After Acute Myocardial Infarction

Abstract

Guidelines advocate primary preventive ICDs for patients with LVEF ≤35% after >40 days after AMI, but a delay of at least 3 months is recommended after revascularization. Implantation of primary preventive ICDs is also recommended for patients with LVEF ≤40%, nonsustained ventricular arrhythmias (ventricular tachyarrhythmias) caused by prior AMI, and inducible ventricular tachyarrhythmias during electrophysiological studies. 13 The optimal timing for ICD implantation has not been evaluated in prospective studies.14 A substudy of Multicenter Automatic Defibrillator Implantation Trial (MADIT) II showed more benefit with ICD in patients with more remote AMI, 15 but post hoc analysis of the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) study implicates that the duration after AMI does not modify Background-Implantable cardioverter-defibrillator therapy improves survival in patients with reduced left ventricular ejection fraction (LVEF) after acute myocardial infarction (AMI). Although the risk of sudden cardiac death is highest in the first month after AMI, there is no survival benefit of early implantable cardioverter-defibrillator implantation, and the optimal time frame has yet to be established. Thus, the aim of this study was to investigate what proportion of post-AMI patients had improved LV function to such an extent that the indication for implantable cardioverter-defibrillator was no longer present. Methods and Results-Patients admitted for AMI with reduced LVEF (≤40%) were eligible for inclusion. Repeat echocardiographic examinations were performed 5 days, 1 month, and 3 months after the AMI. We prospectively included 100 patients with LVEF of 31±5.8% after AMI. At the 1-month follow-up, 55% had an LVEF >35%. The main improvement in LVEF had occurred by 1 month. The mean difference in LVEF over the next 2 months was small, 1.9 percentage units. During the first 9 weeks, 10% of the patients suffered from life-threatening arrhythmias. Conclusions-Most patients have improved LVEF after AMI, and in the majority, the improvement can be confirmed after 1 month, implying that further delay of implantable cardioverter-defibrillator implantation may not be warranted. The aim of this study was to investigate what proportion of patients with reduced LV function after an AMI reached an LVEF >35%, thereby no longer qualifying for ICD treatment. We also investigated the time to improvement to allow earlier identification of possible ICD candidates. MethodsPatients admitted with AMI at Danderyd University Hospital or Södersjukhuset in Stockholm between November 2010 and December 2013 were eligible for participation in the study if a clinical echocardiography showed an LVEF of ≤40%. An AMI was defined according to the second and third universal definitions of myocardial infarction. 19,20 All clinical echocardiographies of potentially eligible patients were reviewed by a participating research cardiologist with echocardiographic expertise who confirmed that the LVEF was indeed ≤40% according to the modified Simpso...

Avoiding Untimely Implantable Cardioverter/Defibrillator Implantation by Intensified Heart Failure Therapy Optimization Supported by the Wearable Cardioverter/Defibrillator—The PROLONG Study

“…Current guidelines recommend primary preventive ICD implantation for patients receiving optimal medical therapy for more than 3 months 1. A recent study on post‐MI patients investigated evolution of LVEF and showed that there is further improvement in LVEF beyond the initial 40 days post‐MI and confirmed the relevant risk for life‐threatening ventricular arrhythmias within the first weeks post‐MI 7. LVEF at presentation, length of hospitalization, previous MI, lateral wall motion abnormality at presentation, and peak troponin were shown to influence LVEF evolution post‐MI 13.…”

“…Early implantation after diagnosis does not improve prognosis in patients with ischemic cardiomyopathy (ICM) and nonischemic cardiomyopathy (NICM) 3, 4, 5. However, patients with reduced LVEF following myocardial infarction (MI) carry a relevant risk for life‐threatening arrhythmias 6, 7. Moreover, even in patients already implanted with an ICD according to guidelines, LVEF may improve with consecutively reduced arrhythmic risk 8…”

Natural History and Implantable Cardioverter‐Defibrillator Implantation After Revascularization for Stable Coronary Artery Disease With Depressed Ejection Fraction

“…We excluded patients presenting with ACS and/or acute MI because ICD use in the post-ACS/post-MI population both has been studied previously and is the subject of ongoing research. 4,7,8 Our investigation has several important findings. Among patients presenting with depressed LVEF (≤35%) and stable CAD requiring revascularization, the majority received guideline-supported care with regard to ICD implantation.…”

“…7,8 We sought to determine the natural history of LVEF recovery following revascularization for stable CAD with an initially depressed LVEF, as well as the number of patients who later did not receive ICDs despite meeting criteria for implantation.…”

Effects of Therapeutic Lifestyle Change Diet and Q10 Plus L-Carnitine Supplementation on Inflammatory Biomarkers of In-Stent Restenosis, Lipid Profile, and Left Ventricular Ejection Fraction in Myocardial Infarction: A Randomized Clinical Trial

“…Q10 plays an essential role in mitochondria electron transport chains for energy production. It could also protect the cardiac tissue from ischemia and reperfusion injury by increasing aerobic energy production that can help improve LVEF (45). Besides, Q10 has antioxidant and membrane stabilizing properties in the cardiac tissue and therefore, can help improve ejection fraction (47).…”