We describe an elderly female who is previously healthy besides an abnormal stress EKG few months ago. She presents with severe chest pain while holding her grand son and improvement in pain with SL Nitro. She had normal EKG and normal troponins. She underwent angiography showing slow flow in all coronary vessels, particularly LAD but no obstruction. She was diagnosed with microvascular angina, sometimes referred to as Cardiac Syndrome X.

Microvascular angina describes coronary microcirculation that are sensitive to vasoconstrictor stimuli and lack capacity to vasodilate appropriately without frank CAD (<50% stenosis). Diagnosis should be suspected in anyone who has episodic chest pain. Patients can have normal EKG between episodes. Some may have mild CAD (<30% stenosis). If they have 30-50%, you will do further testing to measure resistance to blood flow in microcirculation.
Treatment includes risk factor modification for CAD, ASA, Statin, SL nitro PRN and if refractory, BB>CCB.