Abstract: A case of left-main stem ST-elevation myocardial infarction presenting “out of hours” is discussed, wherein an excellent result was achieved with acute thrombolysis, given while the cath lab team was called in to perform percutaneous coronary stenting. Given the ongoing poor outcomes of contemporary therapies for this rare condition, we hypothesize this approach might receive further evaluation.
J INVASIVE CARDIOL 2017;29(11):E155-E156.
Key words: thrombolysis, left-main intervention, ST-elevation myocardial infarction
Left-main stem ST-elevation myocardial infarction (LM-STEMI) is uncommon, but continues to carry a poor prognosis, despite improvements in contemporary therapies.1 A case of LM-STEMI is presented - with a variation in clinical treatment - and is associated with an excellent clinical result.
A 58-year-old previously well male with a 30-min history of severe chest pain and acute diaphoresis presented to a metropolitan tertiary university hospital operating a “24/7” primary percutaneous coronary intervention (PCI) service. Examination was unremarkable except for bibasal crepitations on auscultation of the chest. Electrocardiogram revealed up to 15 mm ST-segment elevation anterolaterally and up to 7 mm reciprocal ST depression inferiorly, with partial right bundle-branch block (Figure 1A). This was thought to be consistent with acute LM-STEMI.
The patient arrived at 7:35 pm, at which time the PCI team would normally be called in, with a delay in needle-to-skin time estimated at 30-40 min. In view of the severity of the ischemia based on a probable LM culprit, possible early heart failure, low perceived bleeding risk, and a hospital PCI protocol that includes thrombolysis in selected cases of early-presentation STEMI, the decision was made to thrombolyze with tenecteplase while simultaneously calling in the PCI team.
Twenty minutes after thrombolysis, there was >50% (but not complete) ST-segment resolution (Figure 1B), with ongoing but lessening pain, such that the patient was then taken immediately to the cardiac catheterization laboratory, with a total door-to-needle time of 62 min. Angiography revealed a 95% thrombotic culprit LM stenosis with TIMI 3 flow distally (Figure 2A), and a very distal right coronary artery lesion (not shown). The culprit was stented uneventfully except for asymptomatic loss of a diminutive circumflex branch (Figure 2B). An intra-aortic balloon pump was not deployed given improved hemodynamics and chest pain resolution at the end of the procedure. Hematemesis occurred within 24 hr secondary to Mallory-Weiss tear. There was a short period on inotropes including levosimendan, with an initial ejection fraction estimated at 35%, after which there was a return to mild left ventricular dysfunction only (echo ejection fraction, 45%). At 3 months, the patient is playing 18 holes of golf daily, and is asymptomatic on medical therapy.
Thirty-day mortality in LM-STEMI remains high (11.7%), particularly in patients with cardiogenic shock (52.0%).1,2 This occurs despite contemporary PCI techniques delivered promptly.1,2 Facilitated PCI – that is, thrombolysis followed by prompt PCI – as occurred here, is not generally practiced, following observation over a decade ago of increased mortality compared to primary PCI.3
In the presented case, thrombolysis resulted in very prompt reperfusion, relieved severe ischemia, and was associated with an excellent outcome. This suggests that for the specific indication of LM-STEMI presenting early with perceived low bleeding risk, thrombolysis might be considered if even a short delay is anticipated prior to definitive treatment with PCI. Further evaluation of this strategy is warranted.
1. Alabas OA, Brogan RA, Hall M, et al. Determinants of excess mortality following unprotected left main stem percutaneous coronary intervention. Heart. 2016;102:1287-1295.
2. Almudarra S, Gale P, Brogan RA, Ludman P, De Belder M, Curzen N. Comparative outcomes after unprotected left main stem percutaneous coronary intervention: a national linked cohort study of 5,065 acute and elective cases from the BCIS Registry (British Cardiovascular Intervention Society). JACC Cardiovasc Interv. 2014;7:717-730.
3. Keeley EC, Boura JA, Grines CL. Comparison of primary and facilitated percutaneous coronary interventions for ST-elevation myocardial infarction: quantitative review of randomised trials. Lancet. 2006;367:579.
From the Cardiac Catheterisation Laboratories, Concord Repatriation General Hospital, Sydney, North South Wales, Australia.
Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. The authors report no conflicts of interest regarding the content herein.
Manuscript submitted March 9, 2017 and accepted March 24, 2017.
Address for correspondence: Associate Professor Harry C. Lowe, FRACP, PhD, Head, Cardiac Catheterisation Laboratories, Concord Repatriation General Hospital, Sydney, NSW, 2139, Australia. Email: firstname.lastname@example.org