Common indications of coronary angiography in high risk ACS patients include new  ischemic changes on the ECG
, troponin-confirmed acute myocardial   injury
, new-onset left ventricular systolic dysfunction  (ejection  fraction <40%)
, newly  diagnosed  moderate-severe  ischemia  on  stress  imaging. For high-risk patients presented with documented AMI and normal epicardial coronary arteries on CCTA or invasive coronary angiography, or  nonobstructive  CAD, CMR  and  echocardiography are useful for evaluation of  nonischemic  cardiomyopathy or myocarditis. Among high risk patients, invasive coronary angiography  provides a comprehensive assessment   of   the   extent and severity of obstructive CAD. The  determination  of  the  severity  of  anatomic  CAD  is  critical  to  guide  the  use  of  coronary  revascularization. Approximately  6%  to  15%  of troponin-positive  ACS occurs  in  the  absence  of  obstructive  CAD. Additional  testing  may  be  helpful to determine the strategy of treatment. Evidence  supports  that  CMR can identify wall motion abnormalities and myocardial edema and distinguish infarct-related scar  from  non-CAD  causes  such  as  myocarditis and nonischemic cardiomyopathy. Performing CMR  within  2  weeks  of  ACS, can  be  useful  to  identify  MI  with  nonobstructive  CAD  (MINOCA) from other causes. The  term  obstructive CAD indicates CAD with ≥50% stenosis. Nonobstructive CAD is used if  CAD <50% stenosis. High risk CAD is defined in the presence of obstructive  stenosis with  left  main  stenosis ≥50% or anatomically significant 3-vessel disease (≥70% stenosis).
Chest pain interventions
Palpitation medical therapy
Anti-stuttering devices
Palpitation surgery
Chest pain medical therapy
Pericardial effusion interventions
Pericardiectomy
Constrictive pericarditis surgery