Discussion
Coronary spasm after cardiac surgery is a rare entity that can be associated to the development of arrythmias, both ventricular fibrillation or ventricular tachycardia and bradycardia and atrioventricular blocks3. It is defined as transient total or subtotal coronary artery occlusion with angina and ischemic ECG changes4. The underlying mechanism in this process is still not clear and it results from the accumulation of multiple triggers including endothelial dysfunction, coronary smooth muscle calcium hypersensitivity, magnesium insufficiency, CBP related inflammation and genetic susceptibility5. Recently, coronary arteries hypersensitivity with vasospasm has been defined as Kounis Syndrome6: anaphylactic response is supposed to be the origin of a spectrum of coronary diseases resulting in microvascular endothelial dysfunction and coronary spasm. Diagnosis may be challenging without invasive examination, so certitude is obtained only after coronary angiography. Anyway, coronary spasm should be suspected in case of electrical instability after cardiac surgery: it occurs especially after surgical myocardial revascularization, rarely after valvular surgery, as reported in literature. Thus this syndrome is unpredictable, promptness in diagnosis and treatment is fundamental. Early recognition and immediate institution of specific treatment can be performed in a hybrid theatre7: open-chest coronary angiography allows evaluation and treatment of patients with early cardiovascular collapse after cardiac surgery. Furthermore, the consequent cardiac events such as coronary artery disease and acute myocardial ischemia play crucial role in patient survival8. Angioplasty (PCI) and coronary stenting are not routinely indicated for patients with focal spasm and minimal artery disease. Spasms may be due to the withdrawal of long-acting oral nitrates or calcium channel blockers and are usually treated with intracoronary nitrates, but it was not our case, for both, as the patient had no therapy preoperatively and coronary spasms did not respond to vasodilators nor to IABP. Moreover, when spasm is refractory to conventional vasodilators, including nitrates, calcium channel blockers, PCI turns out to be a valuable option 9. Stent placement may be effective and moreover life-saving, once hemodynamical instability has developed. Even if stent placement may be a risk, as it may induce itself end-stent spasms10, in our case, the decision of treatment was forced by the emergency situation, as our patient could not be weaned from CBP. The binominal interventional therapy and the opportunity to work in a hybrid setting have a key role in the management and in the clinical consequences.
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