Mortality Related to Periprocedural Myocardial Injury in CTO-PCI
- Periprocedural myocardial infarction (PMI) is more prevalent in patients undergoing PCI for chronic total occlusions.
- Patients with PMI who require multiple lesion treatment, a retrograde approach to therapy, and more stents had a higher rate of mortality at follow-up.
Risks to the myocardium during percutaneous coronary intervention (PCI) have been minimized over the last few decades due to the advancement of interventional cardiology techniques and technology. Adverse events (AEs) following PCI are not uncommon, however, despite the ability of PCI to improve life quality among patients with coronary artery disease. Periprocedural myocardial injury (PMI) is one such AE that can occur during PCI and can be detected in up to 80% of patients.
The Society of Cardiac Angiography and Interventions (SCAI) has suggested that, based on numerous studies seeking to define PMI, a clinically relevant PMI should be defined as a post-PCI CK-MB ≥10 times the upper limit of normal (ULN). Additionally, an elevated troponin level ≥70 times the ULN is also consistent with PMI.
This retrospective analysis published in JACC Cardiovascular Interventions utilized patient data from the CTO registry database, a database enrolling patients who received CTO-PCI with drug-eluting stent (DES) implantation (n=1058). Study researchers examined data to determine the prognosis for patients with PMI following successful chronic total occlusion (CTO) percutaneous coronary intervention (PCI).
Primary endpoint: mortality during follow-up of 4.4 years.
A CK-MB >3 times the upper reference limit (URL) was considered a PMI.
A Cox proportional hazard regression analysis was performed to determine predictors of mortality (Table 1). Patient mortality predictors included:
- Diabetes mellitus
- Diagnosis of acute coronary syndrome
- Heart failure history
- Left anterior descending artery CTO
- Left ventricular ejection fraction
- Renal dysfunction
Mortality occurred in 8.4% (n=89) of patients during follow-up, 5.6% (n=59) of which were caused by a cardiac-related issue. A CK-MB elevation of >3 times and >5 times the URL in 173 failed CTO-PCI patients were 15.6% and 14.5%, respectively. The incidence of PMI was consistently associated with mortality in this patient population.
Patients who had a higher likelihood of suffering from PMI also:
- Had multiple lesions that needed treatment
- History of stroke
- Recent acute coronary syndrome
- Required more stents
- Needed a retrograde approach to therapy
- Had renal insufficiency
In this study, PMI (defined as CK-MB >3x URL) increases long-term mortality risk in patients undergoing CTO-PCI.
- Lee SW, Lee PH, Kang SH, et al. Determinants and Prognostic Significance of Periprocedural Myocardial Injury in Patients With Successful Percutaneous Chronic Total Occlusion Interventions. JACC Cardiovasc Interv. 2016;9(21):2220-2228.