Background-Delayed stent implantation after restoration of normal epicardial flow by a minimalist immediate mechanical intervention aims to decrease the rate of distal embolization and impaired myocardial reperfusion after percutaneous coronary intervention. We sought to confirm whether a delayed stenting (DS) approach (24-48 hours) improves myocardial reperfusion, versus immediate stenting, in patients with acute ST-segment-elevation myocardial infarction undergoing primary percutaneous coronary intervention.
Methods and Results-In the prospective, randomized, open-label minimalist immediate mechanical intervention (MIMI)trial, patients (n=140) with ST-segment-elevation myocardial infarction ≤12 hours were randomized to immediate stenting (n=73) or DS (n=67) after Thrombolysis In Myocardial Infarction 3 flow restoration by thrombus aspiration. Patients in the DS group underwent a second coronary arteriography for stent implantation a median of 36 hours (interquartile range 29-46) after randomization. The primary end point was microvascular obstruction (% left ventricular mass) on cardiac magnetic resonance imaging performed 5 days (interquartile range 4-6) after the first procedure. There was a nonsignificant trend toward lower microvascular obstruction in the immediate stenting group compared with DS group (1.88% versus 3.96%; P=0.051), which became significant after adjustment for the area at risk (P=0.049). Median infarct weight, left ventricular ejection fraction, and infarct size did not differ between groups. No difference in 6-month outcomes was apparent for the rate of major cardiovascular and cerebral events.
Conclusions-The
Background
Heart failure- (HF) and arrhythmia-related complications are the main causes of morbidity and mortality in patients with nonischemic dilated cardiomyopathy (NIDCM). Cardiovascular magnetic resonance (CMR) imaging is a noninvasive tool for risk stratification based on fibrosis assessment. Diffuse interstitial fibrosis in NIDCM may be a limitation for fibrosis assessment through late gadolinium enhancement (LGE), which might be overcome through quantitative T1 and extracellular volume (ECV) assessment. T1 and ECV prognostic value for arrhythmia-related events remain poorly investigated. We asked whether T1 and ECV have a prognostic value in NIDCM patients.
Methods
This prospective multicenter study analyzed 225 patients with NIDCM confirmed by CMR who were followed up for 2 years. CMR evaluation included LGE, native T1 mapping and ECV values. The primary endpoint was the occurrence of a major adverse cardiovascular event (MACE) which was divided in two groups: HF-related events and arrhythmia-related events. Optimal cutoffs for prediction of MACE occurrence were calculated for all CMR quantitative values.
Results
Fifty-eight patients (26%) developed a MACE during follow-up, 42 patients (19%) with HF-related events and 16 patients (7%) arrhythmia-related events. T1 Z-score (p = 0.008) and global ECV (p = 0.001) were associated with HF-related events occurrence, in addition to left ventricular ejection fraction (p < 0.001). ECV > 32.1% (optimal cutoff) remained the only CMR independent predictor of HF-related events occurrence (HR 2.15 [1.14–4.07], p = 0.018). In the arrhythmia-related events group, patients had increased native T1 Z-score and ECV values, with both T1 Z-score > 4.2 and ECV > 30.5% (optimal cutoffs) being independent predictors of arrhythmia-related events occurrence (respectively, HR 2.86 [1.06–7.68], p = 0.037 and HR 2.72 [1.01–7.36], p = 0.049).
Conclusions
ECV was the sole independent predictive factor for both HF- and arrhythmia-related events in NIDCM patients. Native T1 was also an independent predictor in arrhythmia-related events occurrence. The addition of ECV and more importantly native T1 in the decision-making algorithm may improve arrhythmia risk stratification in NIDCM patients.
Trial registration NCT02352129. Registered 2nd February 2015—Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02352129
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.