What are the priority tests and procedures for a patient with a complex medical condition?

Priority-Ranked Tests and Procedures for Complex Medical Conditions

For patients with complex medical conditions, immediately obtain basic biochemical tests, a 12-lead ECG, and resting echocardiography as first-line investigations, with additional testing guided by clinical presentation and suspected diagnoses. 1

Immediate Priority Tests (Perform First)

Biochemical Testing - Core Panel

The following blood tests are Class I recommendations and should be obtained in all patients with suspected or known cardiovascular disease:

• Full blood count including hemoglobin and white cell count 1
• Creatinine measurement and estimation of renal function (creatinine clearance) 1
• Lipid profile including LDL-cholesterol 1
• Fasting plasma glucose and HbA1c to screen for type 2 diabetes mellitus; add oral glucose tolerance test if results are inconclusive 1

High-Sensitivity Troponin

• If clinical instability or acute coronary syndrome is suspected, repeated measurements of troponin using high-sensitivity or ultrasensitive assays are mandatory to rule out myocardial injury 1
• This is a Class I, Level A recommendation and takes precedence when acute pathology is considered 1

Important caveat: Troponin can be elevated in critically ill patients without overt myocardial ischemia, particularly in sepsis, renal failure, and multiorgan dysfunction 2, 3. Do not interpret isolated troponin elevation as definitive evidence of acute coronary syndrome without clinical correlation.

Electrocardiography

• 12-lead resting ECG is recommended in all patients with chest pain without obvious non-cardiac cause 1
• Obtain ECG during or immediately after angina if clinical instability is suspected 1
• In asymptomatic patients with diabetes mellitus, periodic resting ECG is recommended for detection of conduction abnormalities, atrial fibrillation, and silent myocardial infarction 1

Resting Echocardiography

A resting transthoracic echocardiogram is Class I recommended for all patients to assess:

• Exclusion of alternative causes of angina 1
• Identification of regional wall motion abnormalities suggestive of coronary artery disease 1
• Measurement of left ventricular ejection fraction for risk-stratification 1
• Evaluation of diastolic function 1

In patients with hypertension and diabetes showing ECG abnormalities (such as poor R wave progression), echocardiography should assess for left ventricular hypertrophy, hypertension-mediated organ damage, and diabetic cardiomyopathy 4.

Conditional Priority Tests (Based on Clinical Presentation)

Thyroid Function

• Assess thyroid function if there is clinical suspicion of thyroid disorder (symptoms suggesting hyperthyroidism or hypothyroidism as potential causes of ischemia) 1

Liver Function Tests

• Recommended in patients early after beginning statin therapy 1
• If serious hepatic injury with clinical symptoms and/or hyperbilirubinemia occurs, liver enzymes should be checked before considering continuation of lipid-lowering therapy 5

Creatine Kinase

• Measure in patients taking statins who complain of symptoms suggestive of myopathy (unexplained muscle pain, tenderness, or weakness) 1, 5
• Discontinue statin if markedly elevated CK levels occur or if myopathy is diagnosed or suspected 5

BNP/NT-proBNP

• Should be considered in patients with suspected heart failure 1

Chest X-Ray

• Recommended for patients with atypical presentation, signs and symptoms of heart failure, or suspicion of pulmonary disease 1
• Not routinely indicated in straightforward presentations 1

Ambulatory ECG Monitoring

• Recommended in patients with chest pain and suspected arrhythmias (if symptoms may be associated with paroxysmal arrhythmia) 1
• Should NOT be used as routine examination in patients with suspected chronic coronary syndromes 1

Advanced Imaging (Second-Tier, Based on Initial Results)

Non-Invasive Functional Imaging or Coronary CTA

• Recommended as initial test for diagnosing coronary artery disease in symptomatic patients in whom obstructive disease cannot be excluded by clinical assessment alone 1
• Selection should be based on clinical likelihood of disease, patient characteristics affecting test performance, local expertise, and availability 1

Functional Imaging for Myocardial Ischemia

• Recommended if coronary CTA shows disease of uncertain functional significance or is non-diagnostic 1

What NOT to Do - Critical Pitfalls

• Do NOT routinely screen asymptomatic diabetic patients for coronary artery disease with stress testing or imaging, as this does not improve outcomes when risk factors are optimally treated 4
• Do NOT use ambulatory ECG monitoring routinely in suspected chronic coronary syndromes 1
• Do NOT use coronary CTA as routine follow-up in patients with established coronary disease 1
• Do NOT perform invasive coronary angiography solely for risk stratification 1
• Do NOT use ST-segment alterations during supraventricular tachyarrhythmias as evidence of coronary disease 1
• Do NOT routinely assess circulating biomarkers for cardiovascular risk stratification in asymptomatic patients 1

Algorithmic Approach to Test Selection

Step 1: Determine clinical stability

• If unstable or acute coronary syndrome suspected → High-sensitivity troponin (repeated measurements) + immediate ECG 1

Step 2: Obtain core biochemical panel in ALL patients

• Full blood count, creatinine/renal function, lipid profile, glucose/HbA1c 1

Step 3: Obtain 12-lead ECG and resting echocardiography in ALL patients with suspected cardiac disease 1

Step 4: Add conditional tests based on findings

• Thyroid function if clinically indicated 1
• Chest X-ray if atypical presentation or heart failure suspected 1
• Ambulatory ECG only if arrhythmia suspected 1

Step 5: Proceed to advanced imaging only if initial tests suggest obstructive disease and clinical management would change

• Non-invasive functional imaging or coronary CTA based on pretest probability 1