Prognostic impact of chronic total coronary occlusion on long-term outcomes in implantable cardioverter-defibrillator recipients with ischaemic heart disease

Impact of a Chronic Total Coronary Occlusion on the Incidence of Appropriate Implantable Cardioverter-Defibrillator Shocks and Mortality: A Substudy of the Dutch Outcome in ICD Therapy (DO-IT)) Registry

BACKGROUND

Chronic total coronary occlusions (CTO) substantially increase the risk for sudden cardiac death. Among patients with chronic ischemic heart disease at risk for sudden cardiac death, an implantable cardioverter defibrillator (ICD) is the favored therapy for primary prevention of sudden cardiac death. This study sought to investigate the impact of CTOs on the risk for appropriate ICD shocks and mortality within a nationwide prospective cohort.

METHODS AND RESULTS

This is a subanalysis of the nationwide Dutch-Outcome in ICD Therapy (DO-IT) registry of primary prevention ICD recipients in The Netherlands between September 2014 and June 2016 (n=1442). We identified patients with chronic ischemic heart disease (n=663) and assessed available coronary angiograms for CTO presence (n=415). Patients with revascularized CTOs were excluded (n=79). The primary end point was the composite of all-cause mortality and appropriate ICD shocks. Clinical follow-up was conducted for at least 2 years. A total of 336 patients were included, with an average age of 67±9 years, and 20.5% was female (n=69). An unrevascularized CTO was identified in 110 patients (32.7%). During a median follow-up period of 27 months (interquartile range, 24-32), the primary end point occurred in 21.1% of patients with CTO (n=23) compared with 11.9% in patients without CTO (n=27; P=0.034). Corrected for baseline characteristics including left ventricular ejection fraction, and the presence of a CTO was an independent predictor for the primary end point (hazard ratio, 1.82 [95% CI, 1.03-3.22]; P=0.038).

CONCLUSIONS

Within this nationwide prospective registry of primary prevention ICD recipients, the presence of an unrevascularized CTO was an independent predictor for the composite outcome of all-cause mortality and appropriate ICD shocks.

Prognostic impact of coronary chronic total occlusion on recurrences of ventricular tachyarrhythmias and ICD therapies

BACKGROUND

Despite a few studies evaluating the prognostic impact of coronary chronic total occlusion (CTO) in implantable cardioverter defibrillator (ICD) recipients, the impact of CTO on different types of recurrences of ventricular tachyarrhythmias, as well as their predictors has not yet been investigated in CTO patients.

METHODS

A large retrospective registry was used including all consecutive patients with ventricular tachyarrhythmias undergoing coronary angiography at index from 2002 to 2016. Only ICD recipients with CTO were compared to patients without (non-CTO). Kaplan-Meier and Cox regression analyses were applied for the primary end point of first recurrence of ventricular tachyarrhythmias at 5 years. Secondary end points comprised of the different types of recurrences, first appropriate ICD therapy and all-cause mortality at 5 years.

RESULTS

From a total of 422 consecutive ICD recipients with ventricular tachyarrhythmias at index, at least one CTO was present in 25%. CTO was associated with the primary end point of first recurrence of ventricular tachyarrhythmias at 5 years (55% vs. 39%; log rank p = 0.001; HR = 1.665; 95% CI 1.221-2.271; p = 0.001), as well as increased risk of first appropriate ICD therapy (40% vs. 31%; log rank p = 0.039; HR = 1.454; 95% CI 1.016-2.079; p = 0.041) and all-cause mortality at 5 years (26% vs. 16%; log rank p = 0.011; HR = 1.797; 95% CI 1.133-2.850; p = 0.013). Less developed collaterals (i.e., either ipsi- or contralateral compared to bilateral) and a J-CTO score ≥ 3 were strongest predictors of recurrences in CTO patients at 5 years.

CONCLUSION

A coronary CTO even in the presence of less developed collaterals and more complex CTO category is associated with increasing risk of recurrent ventricular tachyarrhythmias at 5 years in consecutive ICD recipients.

Evaluation of the Impact of a Chronic Total Coronary Occlusion on Ventricular Arrhythmias and Long-Term Mortality in Patients With Ischemic Cardiomyopathy and an Implantable Cardioverter-Defibrillator (the eCTOpy-in-ICD Study)

Background

Previous studies report conflicting results about a higher incidence of ventricular arrhythmias in patients with a chronic total coronary occlusion (CTO). We aimed to investigate this association in a large cohort of implantable cardioverter defibrillator patients with long‐term follow‐up.

Methods and Results

All consecutive patients from 1992 onwards who underwent implantable cardioverter defibrillator implantation for ischemic cardiomyopathy at the Leiden University Medical Center were evaluated. Coronary angiograms were reviewed for the presence of a CTO. The occurrence of ventricular arrhythmias and survival status at follow‐up were compared between patients with and patients without a CTO. A total of 722 patients constitute the study cohort (age 66±11 years; 84% males; 74% primary prevention, median left ventricular ejection fraction 30% [first–third quartile: 25–37], 44% received a cardiac resynchronization therapy defibrillator). At baseline, 240 patients (33%) had a CTO, and the CTOs were present for at least 44 (2–127) months. The median follow‐up duration was 4 (2–6) years. On long‐term follow‐up, CTO patients had a higher crude appropriate device therapy rate (37% versus 27%, P=0.010) and a lower crude survival rate (51% versus 67%, P<0.001) compared with patients without a CTO. Corrected for baseline characteristics including left ventricular ejection fraction, the presence of a CTO was an independent predictor for appropriate device therapy.

Conclusions

The presence of a CTO in implantable cardioverter defibrillator patients was associated with more appropriate device therapy and worse prognosis at long‐term follow‐up. Further investigation is warranted regarding a potential beneficial effect of CTO revascularization on the incidence of ventricular arrhythmias.