By Abdul M. Mozid
There is a growing evidence base suggesting improved clinical outcome in stable patients undergoing successful recanalization of a chronic total occlusion (CTO). The benefits include improvements in symptoms, mortality, and need for future coronary artery bypass surgery. Hypothetically, CTO recanalization in the stable setting maybe also be protective if these patients go on to suffer acute closure of a separate coronary artery due to improved collateral supply to the infarct-related artery.
The prevalence of a CTO in a non-infarct related artery (IRA) in patients presenting with acute STEMI ranges from 7%-21% depending on the demographic of the population studied. Some studies have suggested that multivessel disease (MVD) may only be of prognostic importance if a CTO in a non-IRA is present. In the HORIZONS-AMI trial, the presence of a CTO in the non-IRA was shown to be an independent determinate of early and late mortality. We have performed a retrospective analysis of 1435 patients who have undergone primary PCI at our tertiary center in the United Kingdom. A non-IRA CTO was present in 4.7% of patients presenting with STEMI. We found that the presence of a CTO was an independently predictor of mortality at 30 days, with a three-fold increase in risk, but not for long-term mortality. Our real-world study therefore supports the evidence demonstrating poor prognosis associated with the presence of a CTO in a non-IRA. Furthermore, the data from our study suggest that if CTO revascularization is to be performed, it needs to be carried out earlier rather than later.
A recent observational study of 136 patients with a non-IRA CTO, who underwent successful recanalization of the CTO between 7-10 days after STEMI, demonstrated improved cardiac mortality and event-free survival. The on-going EXPLORE trial, a randomized study of non-IRA CTO revascularization within 1 week of primary PCI, will shed further light on the potential benefit of early intervention.
There is therefore increasing evidence that percutaneous revascularization of CTOs in the stable setting may improve future outcome and there may also now be a case for CTO recanalization in the acute setting following a myocardial infarction.
- Mozid AM, Mohdnazri S, Mannakkara NN. Impact of a Chronic Total Occlusion in a Non-Infarct Related Artery on Clinical Outcomes Following Primary Percutaneous Intervention in Acute ST-Elevation Myocardial Infarction. J INVASIVE CARDIOL 2014;26(1):13-16.
A thoughtful commentary on the above article also appears in this month’s issue:
- Antoun P, Breall JA. SINC or Swim (Should We Intervene in Non-Culprit Vessels During STEMI?). J INVASIVE CARDIOL 2014;26(1):16-17.
Further reading on interventions in non-infarct related arteries:
- Suzuki M, Enomoto D, Mizobuchi T, Kazatani Y, Honda K. Impact of chronic total coronary occlusion on microvascular reperfusion in patients with a first anterior ST-segment elevation myocardial infarction. J Invasive Cardiol. 2012 Sep;24(9):428-32.
- Moreno R, Conde C, Perez-Vizcayno MJ et al. Prognostic impact of a chronic occlusion in a noninfarct vessel in patients with acute myocardial infarction and multivessel disease undergoing primary percutaneous coronary intervention. J Invasive Cardiol. 2006 Jan;18(1):16-9.
- Caymaz O, Tezcan H, Fak AS, Toprak A, Tokay S, Oktay A. Measurement of myocardial fractional flow reserve during coronary angioplasty in infarct-related and non-infarct related coronary artery lesions. J Invasive Cardiol. 2000 May;12(5):236-41.