A 42 y.o. woman co one month of intermittent shoulder pain; EMS called in for an acute MI and transmitted the first image.

The EKG in the ED appears below

What could account for the difference in the two EKGs?

Our patient had a spontaneous dissection of the L main, mid LAD and diagonal arteries without atherosclerotic disease. The flap intermittently closed.  The first case of coronary dissection without atherosclerotic disease was reported in 1931 involving a 42 y.o. woman who  presented with sudden cardiac death and a dissection was found on autopsy.. There is an association with fibromuscular dysplasia. Spontaneous coronary dissection accounts for 0.1-4% of all ACS cases.  Among younger women <50 it accounts for 10.8% of patients with ST elevation MI. In a case series 12% of individuals had simultaneous involvement of multiple coronary arteries.

While non-atherosclerotic coronary dissection was previously thought to be related to pregnancy  and the peripartum period, more recently other causes have been reported.  Fibromuscular dysplasia, connective tissue disease , systemic inflammation  and coronary artery spasm have all been implicated.  Isometric exercise increases cardiocirculatory stresses and shear forces against the coronary artery wall and may also be implicated. Cocaine has been associated with coronary dissection as well.

notice the lucency in the circumflex characteristic of a dissection

Coronary artery dissection can be difficult to diagnose on cath where the image is 2-D. For patients with an intimal tear, multiple radiolucent lines separating the true and false lumens may appear with slow contrast clearing. Dissection may also appear as just compression of the lumen and is best seen on optical coherence tomography.

dissection may also appear as narrowing on cath; which can be shown as a dissection on optical coherence tomography.

The treatment includes antiplatelet therapy(asa and clopidogrel)  and beta blockade.  Revascularization can be challenging since PCI would often include long segments at risk for restenosis and the danger of extending the dissection. They are generally treated without stents as was our patient unless they have persistent pain. Thrombolytic therapy should be avoided in cases of dissection because there are reports of extension of the dissection;cath is preferred   Overall the frequency of thrombotic occlusion is higher that the risk of spontaneous dissection so in rural centers thrombolysis should not be withheld.

The natural history of  dissected segments is that they heal spontaneously if patients survive the initial event.   our patient was  initially was placed on a balloon pump  and treated with balloon angioplasty of the LAD and diagonal.  Her troponin peaked at 175.   Renal dopplers did not show fibromuscular dysplasia.  She was sent home with dual antiplatelet therapy and a betablocker. She returned one day after discharge with chest pain which was thought to be due to anxiety.  At that time her trop continued to trend down and she was discharged home.

Hill SF, Sheppard MN. Non-atheroclerotic coronary artery disease associated with sudden cardiac death. Heart 2010;96:119-1125.

Vanzett o G, Berger-Coz E, Barone-Rochette, G et al. Prevalence, therapeutic management and mediu-term prognosis of spontaneous coronary artery dissection: results from a database of 11,605 patients.  Eur J Cardiothorac Surg. 2009;35:250-254.

Saw J, Starovoytov A, ManciniJ, Buller CE. Non-atherosclerotic coronary artery disease in young women. J Am Coll Cardiol. 2011;58:B113.