Table 5: Incidence of medical services related to coronary artery disease (CAD) during the first year following each patient's baseline myocardial perfusion imaging (MPI) study is compared. National Medicare reimbursement data is used to estimate the average total cost per patient. Mean expenditure on preventable diagnostic services is estimated by excluding expenses related to clinically-indicated revascularization procedures.
| SPECT (n = 277) | SPECT-CT (n = 273) | ||
| Patients with additional services within one year | 76 (27%) | 75 (27%) | p = 0.99 |
| Invasive coronary angiography (ICA) | 36 (13%) | 26 (10%) | p = 0.23 |
| Diagnostic ICA with no therapeutic intervention | 22 (8%) | 8 (3%) | p = 0.01 |
| ICA leading to CABG | 6 (2%) | 9 (3%) | p = 0.45 |
| ICA with PCI (but no CABG) | 8 (4%) | 9 (3%) | p = 0.99 |
| Other admissions for CAD | |||
| Myocardial infarction (with no ICA) | 21 (8%) | 21 (8%) | p = 0.99 |
| Chest pain, ruled out for MI | 41 (15%) | 42 (15%) | p = 0.91 |
| Outpatient stress test | |||
| Repeat SPECT MPI | 2 (1%) | 1 (0%) | p = 0.99 |
| Stress echo | 3 (1%) | 4 (1%) | p = 0.72 |
| Exercise EKG | 6 (2%) | 4 (1%) | p = 0.75 |
| Mean total expenditure per patient who had any additional services | |||
| All services | $9,001 | $8,248 | p = 0.11 |
| Preventable diagnostic services only* | $5,740 | $4,288 | p = 0.04 |
CABG: coronary artery bypass graft; PCI: percutaneous intervention; MI: myocardial infarction. *Preventable diagnostic services include chest pain rule-out admissions, repeat stress testing, and diagnostic ICA procedures that did not result in PCI or referral for CABG.