Angina Chest pain - Diagnosis in Air Ambulance
Evaluation and diagnosis of chest pain has always been a issue of ut-most importance in emergency department because of the deadly conditions like acute myocardial infarction, pulmonary embolism, aortic dissection and pneumothorax on one side and the non specific musculoskeletal reasons for the chest pain on another side as cause of chest pain.
The various imaging diagnostic tests considered at this stage are cardiac catheterization, coronary computed tomography angiography (CCTA), cardiac magnetic resonance imaging (CMR), echocardiography (echo), electrocardiogram (ECG), and single-photon emission computed tomography (SPECT).
Seeing the in-appropriate and random use of the various tests American College of Radiology Appropriateness Criteria Committee and the American College of Cardiology have jointly issued the appropriate criteria’s in various clinical situations.
To utilize the appropriate diagnostic modality, we need to first group the cases/presntations into The four clinical scenarios. These include:-
1) Suspected non–ST-segment elevation acute coronary syndrome (NSTE ACS) (10 scenarios)
2) Suspected pulmonary embolism (five scenarios)
3) Suspected acute syndrome of the aorta (three scenarios)
4) Patients for whom a leading diagnosis is problematic or not possible (two scenarios)
Scenario: ECG diagnostic for ST-segment elevation myocardial infarction (STEMI):
Modality : Cardiac catheterization is considered appropriate, with all other imaging modalities considered rarely appropriate.
Scenario : Initial ECG and/or biomarker unequivocally positive for ischemia:
Modality : Cardiac catheterization is considered appropriate, with all other imaging modalities rated as rarely appropriate.
Scenario: Equivocal initial troponin or single troponin elevation without additional evidence of ACS:
Modality : CCTA and rest SPECT were considered appropriate, catheterization rarely appropriate, and resting echo and CMR were graded as M* ( maybe).
Scenario : Patients in the “observational pathway” after initial assessment (typically 9-24 hours out from presentation) with unequivocal evidence for NSTEMI/ACS:
Modality : Cardiac catheterization was considered appropriate and all other imaging modalities including rest and stress modalities graded as M* (may be).
Scenario : Serial ECG and troponins negative for NSTEMI/ACS in the observational time frame:
Modality : CCTA and stress rest echo, CMR, and SPECT were considered appropriate. The committee suggested that low-risk patients in this category may be evaluated as outpatients.
Scenario : Serial ECG or troponins borderline for NSTEMI/ACS:
Modality : CCTA and stress/rest modalities were all considered appropriate and catheterization graded as M(may be).
Scenarios : Suspected pulmonary embolism with either positive D-dimer or high clinical likelihood:
Modality : CT pulmonary angiography and ventilation-perfusion (VQ) scan were considered appropriate.
Scenario : Suspected acute aortic syndrome:
Modality : CT aortography was considered appropriate and all other imaging modalities including MR aortography were graded as M* (may be) in the hemodynamically unstable patient.
Scenario : Suspected acute aortic syndrome in hemodynamically stable patient:
Modality : CT aortography, MR aortography, and transesophageal echo were considered appropriate.
Scenario : Imaging when a definitive diagnosis is problematic or not possible and where the overall likelihood of ACS, pulmonary embolism, or acute aortic syndrome is not low, a “triple-rule-out” CTA to evaluate coronary anatomy, aortic anatomy, and screen for pulmonary embolism was considered appropriate.