Impact of Chronic Total Occlusion Location on LV Function in ST-Segment Elevation Myocardial Infarction Patients

Infarct-related chronic total coronary occlusion and the risk of ventricular tachyarrhythmic events in out-of-hospital cardiac arrest survivors

Introduction

Chronic total coronary occlusion (CTO) has been identified as a risk factor for ventricular arrhythmias, especially a CTO in an infarct-related artery (IRA). This study aimed to evaluate the effect of an IRA-CTO on the occurrence of ventricular tachyarrhythmic events (VTEs) in out-of-hospital cardiac arrest survivors without ST-segment elevation.

Methods

We conducted a post hoc analysis of the COACT trial, a multicentre randomised controlled trial. Patients were included when they survived index hospitalisation after cardiac arrest and demonstrated coronary artery disease on coronary angiography. The primary endpoint was the occurrence of a VTE, defined as appropriate implantable cardioverter-defibrillator (ICD) therapy, sustained ventricular tachyarrhythmia or sudden cardiac death.

Results

A total of 163 patients from ten centres were included. Unrevascularised IRA-CTO in a main vessel was present in 43 patients (26%). Overall, 61% of the study population received an ICD for secondary prevention. During a follow-up of 1 year, 12 patients (7.4%) experienced at least one VTE. The cumulative incidence rate of VTEs was higher in patients with an IRA-CTO compared to patients without an IRA-CTO (17.4% vs 5.6%, log-rank p = 0.03). However, multivariable analysis only identified left ventricular ejection fraction < 35% as an independent factor associated with VTEs (adjusted hazard ratio 8.7, 95% confidence interval 2.2–35.4). A subanalysis focusing on CTO, with or without an infarct in the CTO territory, did not change the results.

Conclusion

In out-of-hospital cardiac arrest survivors with coronary artery disease without ST-segment elevation, an IRA-CTO was not an independent factor associated with VTEs in the 1st year after the index event.

Supplementary Information

The online version of this article (10.1007/s12471-021-01578-3) contains supplementary material, which is available to authorized users.

Long-term outcomes of staged recanalization for concurrent chronic total occlusion in patients with ST-segment elevation myocardial infarction after primary percutaneous coronary intervention

BACKGROUND

In patients with acute ST-segment elevation myocardial infarction (STEMI) who undergo primary percutaneous coronary intervention (PCI), approximately 10% are concomitant with a chronic total occlusion (CTO) in a non-culprit vessel. However, the impact of staged CTO recanalization on prognosis in this cohort remains disputable. This study aimed to compare the long-term outcomes of staged CTO recanalization versus medical therapy in patients with STEMI after primary PCI.

METHODS

Between January 2005 and December 2016, a total of 287 patients were treated with staged CTO-PCI (n = 91) or medical therapy (n = 196) after primary PCI in our center. The primary endpoint was major adverse cardiovascular and cerebrovascular event (MACCE), defined as a composite of all-cause death, nonfatal myocardial infarction (MI), stroke or unplanned revascularization. After propensity-score matching, 77 pairs of well-balanced patients were identified.

RESULTS

The mean follow-up period was 6.06 years. Overall, the incidence of the primary endpoint of MACCE was significantly lower in staged CTO-PCI group than that in medical therapy group in both overall population (22.0% vs. 46.9%; hazard ratio (HR) = 0.48, 95% CI: 0.29-0.77) and propensity-matched cohorts (22.1% vs. 42.9%; HR: 0.48, 95% CI: 0.27-0.86). In addition, staged CTO-PCI was also associated with reduced risk of the composite of cardiac death, nonfatal MI or stroke compared with medical therapy in both overall population (9.9% vs. 26.5%; hazard ratio (HR) = 0.39, 95% CI: 0.19-0.79) and propensity-matched cohorts (9.1% vs. 22.1%; HR: 0.40, 95% CI: 0.16-0.96). After correction of the possible confounders, staged CTO-PCI was independently associated with reduced risks of MACCE (adjusted HR: 0.46, 95% CI: 0.28-0.75), the composite of cardiac death, nonfatal MI or stroke (adjusted HR: 0.45, 95% CI: 0.22-0.94) and all-cause mortality (adjusted HR: 0.32, 95% CI: 0.13-0.83). Moreover, the results of sensitivity analysis were almost concordant with the overall analysis.

CONCLUSIONS

In patients with STEMI and a concurrent CTO who undergo primary PCI, successful staged recanalization of CTO in the non-culprit vessels is associated with better clinical outcomes during long-term follow-up.

Long-term impact of chronic total occlusion recanalisation in patients with ST-elevation myocardial infarction

Background

During primary percutaneous coronary intervention (PCI), a concurrent chronic total occlusion (CTO) is found in 10% of patients with ST-elevation myocardial infarction (STEMI). Long-term benefits of CTO-PCI have been suggested; however, randomised data are lacking. Our aim was to determine mid-term and long-term clinical outcome of CTO-PCI versus CTO-No PCI in patients with STEMI with a concurrent CTO.

Methods

The Evaluating Xience and left ventricular function in PCI on occlusiOns afteR STEMI (EXPLORE) was a multicentre randomised trial that included 302 patients with STEMI after successful primary PCI with a concurrent CTO. Patients were randomised to either CTO-PCI or CTO-No PCI. The primary end point of the current study was occurrence of major adverse cardiac events (MACE): cardiac death, coronary artery bypass grafting and MI. Other end points were 1-year left ventricular function (LVF); LV-ejection fraction and LV end-diastolic volume and angina status.

Results

The median long-term follow-up was 3.9 (2.1–5.0) years. MACE was not significantly different between both arms (13.5% vs 12.3%, HR 1.03, 95% CI 0.54 to 1.98; P=0.93). Cardiac death was more frequent in the CTO-PCI arm (6.0% vs 1.0%, P=0.02) with no difference in all-cause mortality (12.9% vs 6.2%, HR 2.07, 95% CI 0.84 to 5.14; P=0.11). One-year LVF did not differ between both arms. However, there were more patients with freedom of angina in the CTO-PCI arm at 1 year (94% vs 87%, P=0.03).

Conclusions

In this randomised trial involving patients with STEMI with a concurrent CTO, CTO-PCI was not associated with a reduction in long-term MACE compared to CTO-No PCI. One-year LVF was comparable between both treatment arms. The finding that there were more patients with freedom of angina after CTO-PCI at 1-year follow-up needs further investigation.

Clinical trial registration

EXPLORE trial number NTR1108 www.trialregister.nl.

Improved recovery of regional left ventricular function after PCI of chronic total occlusion in STEMI patients: a cardiovascular magnetic resonance study of the randomized controlled EXPLORE trial

BACKGROUND

The Evaluating Xience and left ventricular function in PCI on occlusiOns afteR STEMI (EXPLORE) trial did not show a significant benefit of percutaneous coronary intervention (PCI) of the concurrent chronic total occlusion (CTO) in ST-segment elevation myocardial infarction (STEMI) patients on global left ventricular (LV) systolic function. However a possible treatment effect will be most pronounced in the CTO territory. Therefore, we aimed to study the effect of CTO PCI compared to no-CTO PCI on the recovery of regional LV function, particularly in the CTO territory.

METHODS

Using cardiovascular magnetic resonance (CMR) we studied 180 of the 302 EXPLORE patients with serial CMR (baseline and 4 months follow-up). Segmental wall thickening (SWT) was quantified on cine images by an independent core laboratory. Dysfunctional segments were defined as SWT < 45%. Dysfunctional segments were further analyzed by viability (transmural extent of infarction (TEI) ≤50%.). All outcomes were stratified for randomization treatment.

RESULTS

In the dysfunctional segments in the CTO territory recovery of SWT was better after CTO PCI compared to no-CTO PCI (ΔSWT 17 ± 27% vs 11 ± 23%, p = 0.03). This recovery was most pronounced in the dysfunctional but viable segments(TEI < 50%) (ΔSWT 17 ± 27% vs 11 ± 22%, p = 0.02). Furthermore in the CTO territory, recovery of SWT was significantly better in the dysfunctional segments in patients with Rentrop grade 2-3 collaterals compared to grade 0-1 collaterals to the CTO (16 ± 26% versus 11 ± 24%, p = 0.04).

CONCLUSION

CTO PCI compared with no-CTO PCI is associated with a greater recovery of regional systolic function in the CTO territory, especially in the dysfunctional but viable segments. Further research is needed to evaluate the use of CMR in selecting post-STEMI patients for CTO PCI and the effect of regional LV function recovery on clinical outcome.

TRIAL REGISTRATION

Trialregister.nl NTR1108 , Date registered NTR: 30-okt-2007.