Cardiac Investigations

Troponins 

• protein molecules that regulate the contraction and excitation of striated cardiac muscle. 
• Myocardial injury and necrosis can lead to the release of troponin into the circulation, which can also be secondary to inflammation and apoptosis

• Levels become elevated after a few hours and may remain elevated for seven to 10 days 
• types of troponin that are measured in clinical practice are:
  1. troponin I
  2. troponin T
  3. High-sensitive troponin(Hs-Tn)

High-sensitive Troponin (hs-Trop T and hs-Trop I)

Purpose:

• Introduced to improve detection of myocardial infarction (MI).

Kinetics:

• Different for Troponin T (Trop T) and Troponin I (Trop I).
• hs-Trop T measurement of 30 pg/ml correlates with Trop I level of just above 0.1 ng/ml.
• hs-Trop T of 140 pg/ml correlates with Trop I value of 1.0 ng/ml.

Advantages:

• Detect much lower concentrations of troponin protein.
• Shorten time interval required to identify myocardial injury.
• Allow early implementation of treatment or facilitate early discharge from the emergency department.
• Detect an additional 4% (20% relative increase) of patients with chest pain at increased risk of death or recurrent ischemia from AMI.
• Reciprocal decrease in diagnosis rates of unstable angina in patients presenting with chest pain to the emergency department.

Disadvantages:

• Detect myocardial damage unrelated to acute myocardial ischemia.
• Reduced specificity as more patients with non-ACS causes of myocardial injury have elevated hs-Tn compared with standard assays.

Causes of Elevated Troponin in Absence of Acute Coronary Syndrome (ACS):

• Cardiac Etiology:
  • Cardiac contusion/surgery
  • Post-electrophysiological procedure (ablation) or PPM implantation
  • Aortic dissection
  • Aortic valve disease
  • Hypertrophic cardiomyopathy
  • Tachyarrhythmias
  • Takotsubo cardiomyopathy
  • Infiltrative diseases (e.g., amyloidosis, hemochromatosis, sarcoidosis, scleroderma)
  • Inflammatory diseases (e.g., myocarditis)
• Non-Cardiac Etiology:
  • Rhabdomyolysis (with cardiac injury)
  • Pulmonary embolism; severe pulmonary hypertension
  • Renal failure
  • Acute neurological disease (e.g., cerebrovascular accident, subarachnoid hemorrhage)
  • Critically ill patients (especially with respiratory failure or sepsis)
  • Extreme exertion

Clinical Practice:

• Promptly refer patients with symptoms suggestive of ACS to hospital without first undertaking community troponin testing.

Troponin Test Indications in General Practice:

1. Patient had symptoms of ACS in preceding days, symptoms resolved, clinically stable, and deemed low risk.
2. Patient presents with atypical symptoms and low likelihood of ACS; troponin testing used to ‘rule out’ ACS.

Important Considerations:

• Perform serial troponin test three hours after presentation if symptoms present for <6 hours at clinical review and initial hs-Tn test.
• Late increases in troponin described in about 1% of patients with recurrent chest pain; ongoing clinical risk assessment necessary, including alternative, non-ACS diagnoses.

Pitfalls in General Practice:

• May lead to delay in referral to a hospital with cardiology facilities, resulting in complications of ACS, increased morbidity and mortality.
• Troponin testing should not delay referral of patients with suspected ACS to hospital.
• Not recommended to measure troponin in asymptomatic patients or use as a screening tool due to potential for problematic results and unnecessary investigations.

Additional Considerations:

• Not appropriate to measure serial troponin levels in the community as patients will not be monitored for worsening symptoms and potential complications.
• If a troponin test is ordered in the community:
  • Clearly mark as urgent.
  • Ensure a mechanism is in place for the doctor and patient to be contacted with the results.
  • If unable to receive troponin results and arrange appropriate follow-up (e.g., late in the day, weekends), refer to an emergency department.
• Rapid and substantial increases in hs-Trop T enhance the likelihood of acute MI.

• not appropriate to measure serial troponin levels in the community
  • as the patient will not be monitored for possible worsening symptoms and potential complications.
• If a troponin test is ordered in the community:
  • it should be clearly marked as urgent
  • there should be a mechanism in place for the doctor and patient to be contacted with the results. 
  • If there is a lack of capacity to receive troponin results and arrange appropriate clinical follow-up when performed in the community on low-risk patients (eg late in the day, weekends), then referral to an emergency department is appropriate.

Rapid and substantial increases in hs-trop T enhance the likelihood of acute MI

REPRINTED FROM AUSTRALIAN FAMILY PHYSICIAN VOL. 43, NO. 5, MAY 2014 263

 Chest X-ray

• is a very useful initial study and allows exclusion of causes such as pneumothorax and pneumonia. 
• Pulmonary and mediastinal masses may also be visible or suspected. Signs of cardiac failure may be present.

 

Functional Tests (imaging the heart under haemodynamic stress)

Strongly consider starting aspirin while awaiting tests

Test Name	Indications	Criteria	Pros	Cons

ECG Stress Test (Exercise Treadmill)

– Suitable for patients with a normal ECG who can exercise – Confirm or exclude coronary ischemia – Assess efficacy of treatment in known ischemic heart disease – Best for exercise-induced symptoms, including palpitations – Used for prognosis or diagnosis

– Normal ECG without LBBB – No significant ST changes (e.g., depression > 1 mm) at rest – No ventricular paced rhythm – Ability to exercise up to 85% of maximum predicted heart rate

– Low cost – Short wait times – No radiation – Provides exercise capacity with strong prognostic value

– Lower sensitivity and specificity compared to other tests – Inaccurate for patients who cannot exercise

Stress Echocardiography (Echo)

– Demonstrate coronary ischemia (diagnose IHD) – Assess efficacy of treatment in known IHD patients

– Patients need to be able to exercise – If unable, consider dobutamine stress Echo and discuss with cardiologist

– No radiation exposure – Provides additional information (LV function, PA pressure) – Higher sensitivity and specificity, especially in women – Provides exercise capacity (unless using dobutamine)

– Requires reasonable Echo images (unsuitable for very obese, severe COPD) – Skilled technicians needed, who may be scarce in some regions

Myocardial Perfusion Scan (Nuclear Medicine)

– Demonstrate coronary ischemia (diagnose IHD) – Assess degree of IHD – Suitable for patients who can’t exercise or have LBBB

– Abnormal fixed or reversible ischemia – Normal – Equivocal findings, recommended for further evaluation with CTCA

– Can image obese patients – Assess degree of ischemic heart disease – Provides accurate assessment of LV systolic function – Readily available through medical imaging providers – High negative predictive value

– Relatively low sensitivity – Cost – Radiation exposure – Little exercise information obtained

CT Coronary Angiogram (CTCA)

– Detecting coronary disease in symptomatic individuals with no history of coronary atherosclerosis

– Requires heart rate of 60 bpm (beta blockers given 1-2 days before)- Radiation dose 1.5–3.5 mSv per study

– Very high negative predictive value<br>- Very high sensitivity for occlusive or high-grade stenoses – Shows other cardiac and thoracic structures (valves, chamber wall, defects, lesions)

– Involves radiation – Heavy coronary artery calcification can obscure vessel lumen details – Out-of-pocket expense if referred by a general practitioner

CT Coronary Calcium Scoring

– Useful for asymptomatic women aged 35-70 and men aged 40-60 at intermediate risk (e.g., family history, borderline cholesterol) – Helps in deciding preventive therapy (aspirin, statin) when traditional risk factors are inconclusive – For patients with a calcium score of 0, consider a repeat scan in 5 years but not sooner

– Not recommended for patients at very low risk (<5% absolute 10-year risk) or high risk (>20% absolute 10-year risk) – High-risk examples: diabetics over 60 or with albuminuria, CKD (eGFR < 45 mL/min), BP > 180/110, familial hypercholesterolemia, cholesterol > 7.5 mmol/L – Should be managed aggressively with optimal medical therapy if symptomatic or previously documented CAD

– Fast examination – Requires little preparation – Provides clear risk stratification for future cardiac events

– Place in therapy not well established – Results around average calcium score for age may not aid in decision-making – No Medicare rebate – Involves radiation exposu

ECG Stress Test: Exercise (Treadmill)

Indications:

• Suitable for patients with a normal ECG who can exercise.
• Confirm or exclude coronary ischemia.
• Assess efficacy of treatment in known ischemic heart disease.
• Best for exercise-induced symptoms, including exercise-induced palpitations.
• Used for prognosis or diagnosis.

Criteria:

• Normal ECG without left bundle branch block (LBBB).
• No significant ST changes (e.g., depression > 1 mm) at rest.
• No ventricular paced rhythm.
• Patients must be able to exercise on a treadmill up to 85% of maximum predicted heart rate.

Exclusions:

• Significant arthritis.
• Deconditioning.
• Limiting lung disease.
• Leg claudication or similar.
• Low pretest probability.
• Not recommended for young females aged <60 years due to unreliability.

Pros:

• Low cost.
• Short wait times.
• No radiation exposure.
• Provides exercise capacity, which has strong prognostic value.

Cons:

• Lower sensitivity and specificity compared to other tests.
• Inaccurate in patients who cannot exercise.

ECG Stress Test: Exercise (Treadmill)

Indications:

• Suitable for patients with a normal ECG who can exercise.
• Confirm or exclude coronary ischemia.
• Assess efficacy of treatment in known ischemic heart disease.
• Best for exercise-induced symptoms, including exercise-induced palpitations.
• Used for prognosis or diagnosis.

Criteria:

• Normal ECG without left bundle branch block (LBBB).
• No significant ST changes (e.g., depression > 1 mm) at rest.
• No ventricular paced rhythm.
• Patients must be able to exercise on a treadmill up to 85% of maximum predicted heart rate.

Exclusions:

• Significant arthritis.
• Deconditioning.
• Limiting lung disease.
• Leg claudication or similar.
• Low pretest probability.
• Not recommended for young females aged <60 years due to unreliability.

Pros:

• Low cost.
• Short wait times.
• No radiation exposure.
• Provides exercise capacity, which has strong prognostic value.

Cons:

• Lower sensitivity and specificity compared to other tests.
• Inaccurate in patients who cannot exercise.

Stress Echocardiography (Echo)

Imaging:

• Echocardiography.

Stress:

• Exercise on treadmill, or IV dobutamine if patient can’t exercise.

Indications:

• Demonstrate coronary ischemia (diagnose ischemic heart disease, IHD).
• Assess efficacy of treatment in known IHD patients.

Criteria:

• Patients need to be able to exercise.
• If unable to exercise, consider dobutamine stress Echo and discuss with cardiologist.

Pros:

• No radiation exposure.
• Provides additional information, such as left ventricular (LV) function and pulmonary artery (PA) pressure.
• Higher sensitivity and specificity, especially in women.
• Provides exercise capacity data (unless using dobutamine).

Cons:

• Requires reasonable Echo images, making it unsuitable for some groups (e.g., very obese, severe COPD).
• Skilled and specialized technicians needed, who may be scarce in some regions.

Myocardial Perfusion Scan (Nuclear Medicine)

Imaging:

• Gamma camera.

Stress:

• IV dipyridamole with or without exercise (stationary bike).
• Widely used and available for assessing reversible or fixed myocardial ischemic changes.

Indications:

• Demonstrate coronary ischemia (diagnose ischemic heart disease, IHD).
• Assess degree of IHD.
• Suitable for patients who can’t exercise or have a left bundle branch block (LBBB).

Stratification Groups:

• Abnormal fixed or reversible ischemia.
• Normal.
• Equivocal (non-diagnostic) findings, recommended for further evaluation with CT coronary angiography (CTCA).

Pros:

• Can image obese patients.
• Assess degree of ischemic heart disease.
• Provides accurate assessment of left ventricular (LV) systolic function.
• Readily available through medical imaging providers.
• High negative predictive value.

Cons:

• Relatively low sensitivity.
• Cost.
• Radiation exposure.
• Little exercise information obtained.

Anatomical Tests (Looking for Atherosclerosis)

CT Coronary Angiogram (CTCA)

Instructions:

• Requires a heart rate of 60 beats per minute; beta blockers are given to all patients for 1 to 2 days before the test.
• Radiation doses with the latest scanners are around 1.5–3.5 mSv per study.
  • These doses compare favorably with normal yearly background radiation exposures at sea level.
  • Comparable to or less than radiation levels from invasive coronary angiography.
• Good test for patients with no known coronary disease but involves radiation.

Indications:

• Detecting coronary disease in symptomatic individuals with no history of coronary atherosclerosis.

Interpretation of Results:

• Normal: No treatment needed.
• < 50% Stenosis: Treatment for atherosclerosis.
• > 50% Stenosis: Coronary angiography.

Pros:

• Very high negative predictive value, making it reliable for excluding coronary artery disease (CAD).
• Very high sensitivity for demonstrating occlusive or high-grade stenoses.
• Shows other cardiac and thoracic structures, including:
  • Cardiac valves.
  • Chamber wall thickness and size.
  • Presence of filling defects (e.g., thrombi, tumors).
  • Mediastinal, hilar, and adjacent lung lesions.

Cons:

• Involves radiation exposure.
• Heavy coronary artery calcification can obscure detail of the vessel lumen.
• Out-of-pocket expense if referred by a general practitioner.

CT Coronary Calcium Scoring

Overview:

• Non-invasive test estimating the amount of plaque within coronary arteries using a high-resolution CT scanner.
• Can be ordered alone or in combination with a CT coronary angiogram.
• A calcium score of 0 indicates a very low risk of adverse cardiac events in the next 5 years.
• Not beneficial for patients at very low or very high risk.

Indications:

• Most useful for asymptomatic women aged 35-70 years and men aged 40-60 years who are at intermediate risk (e.g., positive family history or borderline cholesterol).
• Helps in making decisions on preventive therapy (aspirin or statin) when traditional risk factors are inconclusive.
• For patients with a calcium score of 0, consider a repeat scan in 5 years but not sooner.

Exclusions:

• Not recommended for patients at very low risk (<5% absolute 10-year risk) or high risk (>20% absolute 10-year risk) as testing is unlikely to alter management.
• High-risk examples include:
  • Diabetics over 60 years old or with albuminuria.
  • Chronic kidney disease (eGFR < 45 mL/min).
  • Blood pressure > 180/110.
  • Familial hypercholesterolemia.
  • Cholesterol > 7.5 mmol/L.
• Should be managed aggressively with optimal medical therapy if symptomatic or previously documented coronary artery disease.

Pros:

• Fast examination.
• Requires little preparation.
• Provides a clear risk stratification for future cardiac events.

Cons:

• Place in therapy not well established.
• Results around the average calcium score for a person’s age may not aid in decision-making.
• No Medicare rebate available.
• Involves radiation exposure.

\

Presentation	Test
New onset chest pain or equivalent	Stress EchoExercise stress test CT coronary angiogram
Chest pain in a patient with known IHD – possible ischaemia	Stress Echo Myocardial perfusion scan
Worried but well –possible atherosclerosis	Stress Echo CT coronary angiogram
can exercise/walk on treadmill, BMI < 40	ETT/Echo
Prior MI, Obesity, Hx of AF or Arrhythmia	Nuc Med Perfusion
Lung Disease, no Arrhythmia, inability to exercise	Dobutamine Stress
Renal function (GFR ≥ 30) Able to get HR ≤ 65 (w/ or w/o beta-blocker) Normal sinus rhythm No known CAD No IV contrast allergy	CTCA

other tests

Test/Procedure	Indications/Criteria	Pros	Cons
24-Hour Ambulatory Blood Pressure Monitor	Indications: 1. Diagnosis of Hypertension: – White Coat Hypertension – Masked Hypertension 2. Assessment of Treatment Efficacy 3. Suspected Resistant Hypertension 4. Nocturnal Hypertension 5. Episodic Hypertension 6. High Cardiovascular Risk Patients 7. Secondary Hypertension	– Provides a detailed 24-hour blood pressure profile, including nocturnal readings. – Helps differentiate white coat hypertension from sustained hypertension and detect masked hypertension. – Assists in evaluating the effectiveness of antihypertensive therapy. – Improves cardiovascular risk stratification by identifying non-dipping and reverse-dipping patterns.	– No Medicare rebate, leading to out-of-pocket expenses for patients. – Requires patient compliance for accurate readings. – Some patients may find the cuff inflation uncomfortable, particularly at night.
Transthoracic Echocardiogram (TTE)	Indications: – Assess structure and function of the heart (e.g., LV/RV function). – Assess pulmonary pressure. – Assess valvular function.	– Non-invasive. – Provides valuable information for patients with dyspnea, chest pain, palpitations, and heart failure symptoms. – Can be performed at the bedside.	– Image quality can be affected by patient body habitus. – False positives can occur due to technical issues or poor image quality. – False negatives are rare but possible if specific abnormalities are not visualized.
Transoesophageal Echocardiogram (TOE)	Indications: – Further investigation of findings on a TTE.	– Provides greater detail than TTE, especially for posterior cardiac structures.	– Invasive. – Requires sedation. – Probe insertion can cause discomfort and requires conscious sedation. – False positives/negatives are rare but can occur due to probe positioning and patient movement.
Holter Monitoring	Indications: – Investigation of palpitations and syncope. – Assessment of rate control in atrial fibrillation.	– Provides continuous ECG monitoring for 24-48 hours. – Useful for detecting arrhythmias that may not occur during a standard ECG.	– Limited to the monitoring period. – May miss infrequent arrhythmias. – False positives can occur due to artifacts. – False negatives if arrhythmias do not occur during the monitoring period.
Event Monitor (7-Day Ambulatory Cardiac Monitoring)	Indications: – Investigation of infrequent palpitations or syncope/presyncope where 24-hour Holter monitoring was inconclusive.	– Longer monitoring period increases the likelihood of capturing infrequent arrhythmias.	– Requires patient activation during symptomatic episodes. – Compliance and correct use are critical. – Similar to Holter monitoring, false positives can occur due to artifacts. – False negatives if the patient forgets to activate the monitor during symptoms.
Cardiac Implantable Devices (Pacemakers, Defibrillators, Loop Recorders)	Indications: – Routinely checked 2 weeks post-implantation and then every 3 to 12 months. – Can be interrogated in the event of syncopal or presyncopal symptoms. – Check loop recorders soon after the patient experiences an event.	– Provides valuable data on device function and any recorded arrhythmic events. – Can be done remotely, increasing convenience.	– Requires specialized equipment and expertise. – Patient needs to belong to a clinic or physician for proper follow-up.
Tilt Table Test	Indications: – Specialist referral necessary. – Rarely used in the investigation of syncope in general practice.	– Can diagnose orthostatic hypotension and other causes of syncope.	– Invasive and requires specialized equipment. – Time-consuming. – False positives can occur due to patient anxiety. – False negatives if syncope is not reproducible during the test.

24-Hour Ambulatory Blood Pressure Monitor

Indications:

1. Diagnosis of Hypertension:

• White Coat Hypertension: To distinguish between white coat hypertension (elevated blood pressure in a clinical setting) and sustained hypertension.
• Masked Hypertension: When clinic blood pressure readings are normal, but there is a suspicion of elevated blood pressure outside the clinic (e.g., based on home readings or high-risk factors).

2. Assessment of Treatment Efficacy:

• To evaluate the effectiveness of antihypertensive therapy in patients with known hypertension.
• To assess blood pressure control over 24 hours and make treatment adjustments as needed.

3. Suspected Resistant Hypertension:

• To confirm true resistant hypertension in patients whose blood pressure remains elevated despite the use of three or more antihypertensive medications, including a diuretic.

4. Nocturnal Hypertension:

• To assess blood pressure during sleep, especially in patients with obstructive sleep apnea, chronic kidney disease, diabetes, or autonomic dysfunction.
• To detect non-dipping or reverse-dipping patterns, which are associated with higher cardiovascular risk.

5. Episodic Hypertension:

• To investigate suspected episodic hypertension or fluctuating blood pressure levels that are not captured during routine office visits.

6. High Cardiovascular Risk Patients:

• To assess blood pressure in patients at high cardiovascular risk, such as those with diabetes, chronic kidney disease, or a history of cardiovascular events.

7. Secondary Hypertension:

• To aid in the diagnosis of secondary hypertension when there is a clinical suspicion based on history, physical examination, or initial investigations.

Criteria:

1. Indications for Ambulatory Blood Pressure Monitoring (ABPM):

• Suspected white coat hypertension in patients with persistently elevated office blood pressure but normal home blood pressure readings.
• Suspected masked hypertension in patients with normal office blood pressure but elevated home or occasional high readings.
• Evaluation of blood pressure variability and nocturnal blood pressure patterns.
• Assessment of the efficacy of antihypertensive treatment in patients with known hypertension.
• Confirmation of resistant hypertension.

2. Patient Selection:

• Patients with newly diagnosed hypertension to confirm the diagnosis before initiating lifelong therapy.
• Patients with previously diagnosed hypertension who have unexplained variability in office blood pressure readings.
• Patients with symptoms suggestive of hypotension while on antihypertensive therapy.
• Patients with target organ damage (e.g., left ventricular hypertrophy, retinopathy) despite normal office blood pressure readings.

3. Contraindications:

• Not typically indicated in patients with a very low pre-test probability of hypertension or those with established cardiovascular disease where the diagnosis is clear.
• Patients with severe hypertension who require immediate treatment rather than further diagnostic evaluation.

Pros:

• Comprehensive Profile: Provides a detailed 24-hour blood pressure profile, including nocturnal readings.
• White Coat and Masked Hypertension: Helps in differentiating white coat hypertension from sustained hypertension and detecting masked hypertension.
• Treatment Monitoring: Assists in evaluating the effectiveness of antihypertensive therapy.
• Risk Stratification: Improves cardiovascular risk stratification by identifying non-dipping and reverse-dipping patterns.

Cons:

• Cost: No Medicare rebate, leading to out-of-pocket expenses for patients.
• Compliance: Requires patient compliance for accurate readings, which can sometimes be challenging.
• Discomfort: Some patients may find the cuff inflation uncomfortable, particularly at night, which can affect sleep quality and compliance.

Transthoracic Echocardiogram (TTE)

Indications:

• Assess structure and function of the heart (e.g., LV/RV function).
• Assess pulmonary pressure.
• Assess valvular function.

Pros:

• Non-invasive.
• Provides valuable information for patients with dyspnoea, chest pain, palpitations, and heart failure symptoms.
• Can be performed at the bedside.

Cons:

• Image quality can be affected by patient body habitus.
• False positives can occur in cases of technical issues or poor image quality.
• False negatives are rare but possible if specific abnormalities are not visualized.

Transoesophageal Echocardiogram (TOE)

Indications:

• Further investigation of findings on a TTE.

Pros:

• Provides greater detail than TTE, especially for posterior cardiac structures.

Cons:

• Invasive.
• Requires sedation.
• Probe insertion can cause discomfort and requires conscious sedation.

False Positives/Negatives:

• False positives/negatives are rare but can occur due to probe positioning and patient movement.

What to Watch Out For:

• Requires cardiology assessment before the test.
• Monitor for potential complications from sedation and esophageal injury.

Holter Monitoring

Indications:

• Investigation of palpitations and syncope.
• Assessment of rate control in atrial fibrillation.

Pros:

• Provides continuous ECG monitoring for 24-48 hours.
• Useful for detecting arrhythmias that may not occur during a standard ECG.

Cons:

• Limited to the monitoring period.
• May miss infrequent arrhythmias.
• False positives can occur due to artifacts.
• False negatives if arrhythmias do not occur during the monitoring period.

Event Monitor (7-Day Ambulatory Cardiac Monitoring)

Indications:

• Investigation of infrequent palpitations or syncope/presyncope where 24-hour Holter monitoring was inconclusive.
• investigation of infrequent palpitations or syncope/presyncope where the 24 hours of cardiac monitoring with a Holter has not provided a diagnosis

Pros:

• Longer monitoring period increases the likelihood of capturing infrequent arrhythmias.

Cons:

• Requires patient activation during symptomatic episodes.
• Compliance and correct use are critical.
• Similar to Holter monitoring, false positives can occur due to artifacts.
• False negatives if the patient forgets to activate the monitor during symptoms.

Cardiac Implantable Devices (Pacemakers, Defibrillators, Loop Recorders)

Indications:

• Routinely checked 2 weeks post implantation and then every 3 to 12 months, but can be interrogated in the event of syncopal or presyncopal symptoms (most record tachycardic events including atrial fibrillation and ventricular tachycardia).
• Remote monitors may be used.
• Check loop recorders soon after the patient experiences an event.
• Patients will belong to a clinic or physician and can contact them to arrange check
• Ensure timely follow-up and interrogation after symptomatic events.

Pros:

• Provides valuable data on device function and any recorded arrhythmic events.
• Can be done remotely, increasing convenience.

Cons:

• Requires specialized equipment and expertise.
• Patient needs to belong to a clinic or physician for proper follow-up.

Tilt Table Test

Indications:

• Specialist referral necessary.
• Rarely used in the investigation of syncope in general practice.
• Ensure patient is referred to a specialist center for this test.
• Monitor for potential complications during the test.

Pros:

• Can diagnose orthostatic hypotension and other causes of syncope.

Cons:

• Invasive and requires specialized equipment.
• Time-consuming.
• False positives can occur due to patient anxiety.
• False negatives if syncope is not reproducible during the test.