Assessment of diastolic heart function--experience with 16-gated myocardial perfusion SPECT

Area of Science:

• Cardiology
• Nuclear Medicine
• Diagnostic Imaging

Background:

• Ischaemic heart disease (IHD) remains a significant global health concern.
• Current diagnostic focus often emphasizes epicardial stenosis and surgical interventions, potentially overlooking early cardiac functional impairments.
• Diastolic dysfunction, an early indicator of cardiac issues, is frequently undetected in routine evaluations.

Purpose of the Study:

• To evaluate the utility of 16-gated SPECT myocardial perfusion imaging (MPI) in assessing cardiac function, particularly diastolic dysfunction, in patients with suspected coronary artery disease (CAD).
• To determine if MPI can provide comprehensive functional assessment beyond perfusion, aiding in patient management and symptom correlation.

Main Methods:

• 121 patients with suspected CAD underwent gated myocardial perfusion imaging (MPI) using SPECT-CT with attenuation correction.
• Diastolic function was assessed using 16-gated SPECT MPI data.
• Image quality was enhanced by SPECT-CT attenuation correction.

Main Results:

• MPI revealed no inducible ischaemia in 60% of patients, avoiding further invasive procedures.
• 40% of patients demonstrated inducible ischaemia, necessitating further evaluation and intervention.
• Among all patients, 10% exhibited both left ventricular (LV) systolic and diastolic dysfunction.
• A significant finding was that 66% of patients had isolated diastolic dysfunction.
• Notably, 40% of patients with normal systolic function and no ischaemia presented with symptoms like chest heaviness or angina equivalents, linked to diastolic dysfunction.

Conclusions:

• Gated myocardial perfusion imaging (MPI) is a valuable tool for evaluating suspected coronary artery disease (CAD).
• Beyond assessing perfusion, MPI provides crucial functional insights into both systolic and diastolic cardiac function.
• This comprehensive functional data aids in understanding patient symptomatology and informs clinical management decisions, potentially preventing unnecessary invasive procedures.