Particular evolution in a 72-year-old diabetic patient with acute coronary syndrome

Although the majority of diabetic patients with myocardial infarction have angiographic evidence of significant coronary artery disease, they can also experience myocardial infarctions with non-obstructive coronary arteries (MINOCA). We present the case of a 72 years old diabetic and hypertensive woman admitted for progressive dyspnoea. She affirmed long-term moderate effort retrosternal pain, resolving with rest. Clinically there were congestive heart failure signs. ECG showed sinus tachycardia, ST segment elevation in leads V1-V5 and biphasic T waves V4-V6. Cardiac necrosis markers were slightly elevated and echocardiography revealed akinetic interventricular septum, severe global left ventricular dysfunction (left ventricular ejection fraction – LVEF – of 35%) with elevated filling pressures. Coronary angiography did not show any significant stenosis, but during the procedure a significant left anterior descending coronary artery spasm was registered. Under medical treatment ST elevation resolved, LVEF increased to 45% in a week. Starting 10-th day after admission the patient developed symptomatic sinus bradycardia, sinus pauses, isorhythmic atrio-ventricular dissociation and junctional escape rhythm. After beta blockers were stopped, the conduction disturbances did not improve and patient received a DDDR pacemaker. Our final diagnosis was MINOCA due to coronary spasm and microvascular coronary dysfunction, in an uncontrolled diabetic and dyslipidemic patient. The conduction disturbancies needing permanent cardiac pacing seemed to be due to a latent sinus node dysfunction unmasked by beta blockers administration. MINOCA has several possible etiologies, sometimes atypical evolution and poses many challenges to the practitioner.