Introduction: Atypical ischaemic symptoms and comorbidities in the elderly population make the diagnosis of coronary artery disease (CAD) challenging. Since the role of myocardial perfusion imaging (MPI) in the diagnostic assessment of CAD has been extensively evaluated in middle-aged ambulatory patients, there is limited data for its application in elderly hospitalized patients, particularly those ≥75 years of age.
Purpose: To assess the impact of MPI on decision for coronary angiography in hospitalized elderly patients (≥75 years) with suspected CAD in comparison to younger patients.
Methods: In the retrospective study, data of consecutive hospitalized patients with suspected CAD admitted to MPI from June 2014 to June 2017 were analysed. Patients were categorized into “elderly” (≥75 years) and “younger” (<75 years) groups. The clinical characteristics and coronary angiography rates were identified by manually reviewing the patients' records.
Results: 362 patients with mean age 71±3 years (range 30–92 years) (43.4%women, 84% arterial hypertension, 34% diabetes mellitus, 41.7% previous myocardial infarction or revascularization, 88.9% chest pain) were studied. 155 patients were ≥75 years old (mean age 81.4±4.4). Elderly patients had a higher prevalence of women (55.5% vs. 34.3%, p<0.01) and arterial hypertension (89% vs. 79%, p<0.01) and were less likely to have hyperlipidemia (70.1% vs. 81.0%, p<0.05) and history of smoking (4.5% vs. 23.0%, p<0.01) than younger patients. Elderly had more concomitant diseases than younger patients (2±1.5 vs. 1.5±1.5, p<0.01). All patients underwent a 2-day stress/rest 99mTc tetrofosmin (Myoview, GE Healthcare) myocardial perfusion single photon emission computed tomography. Elderly patients underwent significantly more pharmacological stress testing than younger (94.2% vs. 75%, p<0.01). MPI confirmed ischaemia in 168 (46.4%) patients. Ischaemia was more prevalent in younger than in elderly patients (51.7% vs. 39.3%, p<0.05). Result of MPI had a significant influence on the decision for coronary angiography in both groups (performed in 75.6% of patients with ischaemia vs. 7% patients without ischaemia, p<0.001). The referral rate for cardiac catheterization was not significantly different between elderly and younger patients with ischaemia (68.9% vs 79.4%, NS). Ischaemia on MPI was the most predictive variable for referral to coronary angiography in elderly (odds ratio 23.0, p<0.001).
Conclusions: MPI is a safe non-invasive diagnostic method in elderly hospitalized patients. Abnormal MPI is a powerful predictor for in-hospital coronary angiography independent of the patient's age. Thus, MPI is an effective gatekeeper for coronary angiography in both, elderly and younger hospitalized patients with suspected CAD.