What are the absolute contraindications for Stress ECG (Electrocardiogram), CT (Computed Tomography) coronary angio, Stress Echo (Echocardiogram), and when to choose PCI (Percutaneous Coronary Intervention) vs CABG (Coronary Artery Bypass Grafting) considering FFR (Fractional Flow Reserve) and SYNTAX score, as well as contraindications for CRT (Cardiac Resynchronization Therapy) devices, ICD (Implantable Cardioverter-Defibrillator) devices, permanent and transient pacemakers, Holter monitor, ambulatory BP (Blood Pressure) monitor, loop implants, and ablation for AF (Atrial Fibrillation), PVC (Premature Ventricular Contraction), SVT (Supraventricular Tachycardia) according to the latest ESC (European Society of Cardiology) and ACC (American College of Cardiology) guidelines?

Absolute Contraindications for Cardiac Diagnostic Tests and Interventional Procedures

The most definitive contraindications for cardiac diagnostic tests and interventions are based on patient safety factors that significantly increase morbidity and mortality risk, with specific test selection guided by clinical presentation, anatomical considerations, and hemodynamic status.

Stress ECG Absolute Contraindications 1

• High-risk unstable angina or acute myocardial infarction (<2 days)
• Uncontrolled heart failure
• Significant cardiac arrhythmias (e.g., ventricular tachycardia, complete atrioventricular block)
• Severe symptomatic aortic stenosis
• Severe systemic arterial hypertension (>200/110 mmHg)
• Abnormal resting ECG that limits interpretation:
  • Left bundle branch block
  • Wolff-Parkinson-White pattern
  • Ventricular paced rhythm
  • Digoxin effect with ST changes
• Inability to achieve >5 METs or unsafe to exercise

CT Coronary Angiography Absolute Contraindications 1

• Pregnancy (due to radiation exposure)
• Severe renal dysfunction (GFR <30 mL/min/1.73m²)
• Allergy to iodinated contrast media (unless adequately pre-medicated)
• Inability to cooperate with breath-hold instructions
• Uncontrolled tachyarrhythmias (causes motion artifacts)
• Severe obesity limiting image quality

Stress Echocardiography Absolute Contraindications 1

For exercise stress echo:

• High-risk unstable angina, active ACS or AMI (<2 days)
• Serious ventricular arrhythmias or high risk for arrhythmias
• Limited acoustic windows (e.g., in COPD patients)
• Inability to reach target heart rate

For pharmacological (dobutamine) stress echo:

• Recent use of dipyridamole or dipyridamole-containing medications
• Significant hypotension (SBP <90 mmHg)
• Hemodynamically significant LV outflow tract obstruction
• Severe systemic arterial hypertension (>200/110 mmHg)
• Contraindications to atropine:
  • Narrow-angle glaucoma
  • Myasthenia gravis
  • Obstructive uropathy
  • Obstructive gastrointestinal disorders

When to Choose PCI vs. CABG 1

Choose PCI for:

• Single-vessel disease
• Two-vessel disease without proximal LAD involvement
• Patients with high surgical risk
• Patients requiring urgent revascularization
• Patients with prior CABG with suitable anatomy
• Patient preference with suitable anatomy

Choose CABG for:

• Left main stenosis in patients expected to survive >1 year with good functional status
• Three-vessel disease, especially with proximal LAD involvement
• Two-vessel disease with proximal LAD involvement
• Diabetes with multi-vessel disease
• Complex coronary anatomy unsuitable for PCI
• Need for concurrent valve surgery

Decision Tools:

• SYNTAX Score: Quantifies coronary lesion complexity

  • Low score (0-22): Favors PCI
  • Intermediate score (23-32): Consider individual factors
  • High score (>33): Favors CABG

• FFR (Fractional Flow Reserve):

  • FFR ≤0.80: Indicates hemodynamically significant stenosis requiring intervention
  • FFR >0.80: Medical therapy may be appropriate

Cardiac Device Contraindications

CRT Devices Absolute Contraindications:

• Life expectancy <1 year despite CRT
• Right bundle branch block with left anterior or posterior fascicular block (reduced response)
• QRS duration <130 ms (reduced benefit)
• Irreversible cause of heart failure

ICD Devices Absolute Contraindications:

• Terminal illness with life expectancy <6 months
• Incessant ventricular tachycardia or fibrillation
• Psychiatric conditions preventing proper device management
• NYHA Class IV heart failure refractory to medication and not a candidate for transplant

Permanent Pacemaker Absolute Contraindications:

• Transient causes of bradycardia (medication effect, electrolyte abnormality)
• Asymptomatic sinus bradycardia or first-degree AV block
• Infection at implantation site

Transient Pacemaker Absolute Contraindications:

• When permanent pacing is indicated
• Infection at insertion site
• Severe coagulopathy

Monitoring Devices Contraindications

Holter Monitor:

• Skin conditions preventing electrode attachment
• Inability to maintain the device for required monitoring period

Ambulatory BP Monitor:

• Severe coagulopathy (risk of bleeding under cuff)
• Extremely large arm circumference exceeding available cuff sizes
• Severe anxiety triggered by repeated measurements

Loop Implants:

• Active infection
• Severe coagulopathy
• Allergy to device materials

Ablation Procedure Contraindications

AF Ablation Absolute Contraindications:

• Left atrial thrombus
• Active infection or endocarditis
• Severe uncontrolled heart failure
• Pregnancy (due to radiation exposure)
• Inability to receive anticoagulation

PVC Ablation Absolute Contraindications:

• PVCs originating from papillary muscles (higher complication risk)
• Active myocarditis
• Reversible causes of PVCs (electrolyte abnormalities, medication effects)

SVT Ablation Absolute Contraindications:

• Active infection or endocarditis
• Mechanical prosthetic valve when approach requires crossing the valve
• Intracardiac thrombus

3D Ablation in AF, PVC, SVT Additional Contraindications:

• Severe renal dysfunction limiting contrast use
• Electromagnetic interference from implanted devices incompatible with mapping systems
• Anatomical variants making catheter navigation hazardous

Remember that these contraindications are based on the most recent guidelines available, with patient safety being the primary consideration in all cases. The decision to proceed with any diagnostic test or intervention should always prioritize minimizing morbidity and mortality risk.