Myoview (Tetrofosmin)

Myoview is used in myocardial perfusion imaging to evaluate coronary blood flow and detect cardiac pathology.

• Myocardial perfusion imaging: provides high‑resolution SPECT images of myocardial blood flow, allowing identification of perfusion defects and quantification of ischemic burden.
• Coronary artery disease detection: facilitates non‑invasive assessment of coronary artery stenosis severity, supporting clinical decision‑making for medical or interventional therapy.
• Myocardial viability assessment: distinguishes viable from scarred myocardium, guiding revascularization strategies in patients with left ventricular dysfunction.
• Risk stratification: contributes to prognostic evaluation by correlating perfusion abnormalities with future cardiac events.

• Technetium‑99m tetrofosmin is a lipophilic cation that readily crosses cell membranes and accumulates in myocardial cells in proportion to regional blood flow. After intravenous injection, the technetium‑99m label emits gamma photons detected by SPECT cameras. Within the myocardium, tetrofosmin localizes in mitochondria, providing a quantitative image of perfusion that reflects coronary artery circulation. The rapid uptake and stable retention allow imaging within minutes, while clearance from non‑cardiac tissues reduces background activity.

Adverse reactions to Myoview are generally infrequent but may occur following intravenous administration of the radiopharmaceutical.

Common Side Effects

• Nausea: mild transient feeling of queasiness.
• Headache: mild to moderate headache shortly after injection.
• Dizziness: temporary light‑headedness.
• Injection site pain: brief discomfort at the venipuncture site.
• Flushing: transient warmth or redness of the skin.

Serious or Rare Side Effects

• Anaphylactic reaction: severe allergic response requiring immediate medical attention.
• Hypotension: marked drop in blood pressure post‑injection.
• Arrhythmia: new or worsening cardiac rhythm disturbances.
• Myocardial infarction: rare occurrence of heart attack following the procedure.
• Severe bronchospasm: acute airway constriction in susceptible individuals.

When using Myoview, clinicians should observe specific precautions to ensure patient safety and optimal image quality.

• Assess renal function: evaluate kidney performance as impaired clearance may affect tracer distribution.
• Review allergy history: confirm no prior hypersensitivity to technetium‑99m compounds or tetrofosmin.
• Ensure adequate hydration: encourage fluid intake to promote rapid renal elimination of excess tracer.
• Avoid use in unstable cardiac patients: defer in individuals with severe heart failure or acute ischemia.
• Monitor vital signs: observe blood pressure and heart rate during and after injection.
• Store at 2‑8 °C: keep refrigerated, protect from light, do not freeze or shake the vial.

Myoview may interact with other agents that influence cardiac imaging or tracer distribution.

Major Interactions (Avoid)

• Concurrent radiopharmaceuticals: administration of other nuclear medicine agents within 24 h can interfere with image interpretation.
• Iodinated contrast media: use within 24 h may alter myocardial uptake and affect SPECT results.
• High‑dose caffeine: ingestion shortly before the test can reduce tracer uptake and compromise image quality.

Moderate Interactions (Monitor Closely)

• Beta‑blockers: may modify heart rate and affect perfusion patterns, requiring adjustment of the imaging protocol.
• Calcium channel blockers: can influence coronary vasodilation and alter tracer distribution.
• Antioxidant supplements: high doses of vitamin C or E may affect radiotracer kinetics and should be documented.