title: The association between ischemic and jeopardized myocardia and all-cause mortality in patients with peripheral artery disease.
abstract: Peripheral artery disease (PAD) is associated with increased mortality and concomitant coronary artery disease (CAD). However, it is unclear whether uncovering the presence of functional coronary ischemia by single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) would further help stratifying that excess risk. From January 2000 to 2009, 4294 individuals underwent cardiac stress testing within 180 days of ankle-brachial index (ABI) measurements. Of these, 645 had PAD and SPECT MPI stress testing. Abnormal ABI was defined as ⩽ 0.9 or prior lower extremity arterial revascularization. Myocardial ischemic burden and total jeopardized myocardium were represented by the summed difference score (SDS) and summed stress score (SSS), respectively. Univariate and multivariable Cox proportional hazard analyses were used to study the impact of SDS and SSS on all-cause mortality. Additionally, using a hierarchical approach, we examined the step-wise addition of post-stress test coronary and lower extremity arterial revascularizations as time-varying covariates on outcomes. We found no significant difference in all-cause mortality between patients with ischemic myocardium (SDS > 0) and those without (SDS = 0) (adjusted HR: 0.94, 95% CI: 0.53-1.69; p = 0.84). Similarly, the presence of jeopardized myocardium (SSS > 0) did not have a significant impact on mortality (adjusted HR: 1.16, 95% CI: 0.67-2.00; p = 0.59). Moreover, adjustment for post-testing coronary and lower extremity arterial revascularizations did not affect our results. In conclusion, ischemic and jeopardized myocardia are not predictors of all-cause mortality in PAD; thus, SPECT MPI does not appear to be a useful risk stratification tool in these patients.
authors.affiliation: Medicine Institute, Department of Hospital Medicine, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Tarek A
authors.initials: TA
authors.lastname: Hammad
authors.affiliation: Heart and Vascular Institute, Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Rayan
authors.initials: R
authors.lastname: Yousefzai
authors.affiliation: Medicine Institute, Department of Hospital Medicine, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Sridhar
authors.initials: S
authors.lastname: Venkatachalam
authors.affiliation: Heart and Vascular Institute, Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Ashley
authors.initials: A
authors.lastname: Lowry
authors.affiliation: Heart and Vascular Institute, Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Heather L
authors.initials: HL
authors.lastname: Gornik
authors.affiliation: Heart and Vascular Institute, Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Wael
authors.initials: W
authors.lastname: Jaber
authors.affiliation: Heart and Vascular Institute, Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: John R
authors.initials: JR
authors.lastname: Bartholomew
authors.affiliation: Heart and Vascular Institute, Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Soo Hyun
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Heart and Vascular Institute, Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Manuel
authors.initials: M
authors.lastname: Cerqueira
authors.affiliation: Department of Vascular Surgery, Greenville Hospital System, Greenville, SC, USA.
authors.forename: Bruce H
authors.initials: BH
authors.lastname: Gray
authors.affiliation: Heart and Vascular Institute, Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Eugene H
authors.initials: EH
authors.lastname: Blackstone
authors.affiliation: Heart and Vascular Institute, Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, OH, USA shishem@ccf.org.
authors.forename: Mehdi H
authors.initials: MH
authors.lastname: Shishehbor
mesh_terms: D000368:Aged; D055109:Ankle Brachial Index; D003326:Coronary Circulation; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging / Q000401:mortality* / Q000473:pathology / Q000503:physiopathology; D055414:Myocardial Perfusion Imaging / Q000379:methods; D009206:Myocardium / Q000473:pathology*; D058729:Peripheral Arterial Disease / Q000175:diagnosis / Q000401:mortality* / Q000503:physiopathology; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D015899:Tomography, Emission-Computed, Single-Photon; D014665:Vasodilator Agents / Q000008:administration & dosage
chemical_list: D014665:Vasodilator Agents
keywords: SPECT MPI; cardiac stress testing; imaging; mortality; peripheral artery disease; risk stratification