Kent G. Meredith

Surgical Revascularization Is Associated With Improved Long-Term Outcomes Compared With Percutaneous Stenting in Most Subgroups of Patients With Multivessel Coronary Artery Disease Results From the Intermountain Heart Registry

Background— Coronary artery bypass surgery (CABG) and percutaneous coronary intervention with stenting (PCI-S) are both safe and effective approaches for revascularization in patients with multivessel coronary artery disease. However, conflicting information exists when comparing the efficacy of the two methods. In this study, we examined the outcomes of major adverse cardiovascular events and death for subgroups of typical “real-world” patients undergoing coronary revascularization in the modern era. Methods and Results— Patients were included if they were revascularized by CABG or PCI-S, had ≥5 years of follow-up, and had ≥2-vessel disease. Patients were followed for an average of 7.0±3.2 years for incidence of death and major adverse cardiovascular events (death, myocardial infarction, or repeat revascularization). Multivariate regression models were used to correct for standard cardiac risk factors including age, sex, hyperlipidemia, diabetes mellitus, family history of coronary artery disease, smoking, hypertension, heart failure, and renal failure. Subgroup analyses were also performed, stratified by age, sex, diabetes, ejection fraction, and history of PCI-S, CABG, or myocardial infarction. A total of 6369 patients (CABG 4581; PCI-S 1788) were included. Age averaged 66±10.9 years, 76% were male, and 26% were diabetic. Multivariate risk favored CABG over PCI-S for both death (hazard ratio 0.85; P=0.001) and major adverse cardiovascular events (hazard ratio 0.51; P<0.0001). A similar advantage with CABG was also found in most substrata, including diabetes. Conclusions— In this large observational study of patients undergoing revascularization for multivessel coronary artery disease, a long-term benefit was found, in relationship to both death and major adverse cardiovascular events, for CABG over PCI-S regardless of diabetic status or other stratifications.

Short‐Term Exposure to Fine Particulate Matter Air Pollution Is Preferentially Associated With the Risk of ST‐Segment Elevation Acute Coronary Events

Background Air pollution is associated with greater cardiovascular event risk, but the types of events and specific persons at risk remain unknown. This analysis evaluates effects of short‐term exposure to fine particulate matter air pollution with risk of acute coronary syndrome events, including ST‐segment elevation myocardial infarction, non–ST‐segment elevation myocardial infarction, unstable angina, and non–ST‐segment elevation acute coronary syndrome. Methods and Results Acute coronary syndrome events treated at Intermountain Healthcare hospitals in urban areas of Utahs Wasatch Front were collected between September 1993 and May 2014 (N=16 314). A time‐stratified case‐crossover design was performed matching fine particulate matter air pollution exposure at the time of each event with referent periods when the event did not occur. Patients served as their own controls, and odds ratios were estimated using nonthreshold and threshold conditional logistic regression models. In patients with angiographic coronary artery disease, odds ratios for a 10‐μg/m3 increase in concurrent‐day fine particulate matter air pollution >25 μg/m³ were 1.06 (95% CI 1.02–1.11) for all acute coronary syndrome, 1.15 (95% CI 1.03–1.29) for ST‐segment elevation myocardial infarction, 1.02 (95% CI 0.97–1.08) for non–ST‐segment elevation myocardial infarction, 1.09 (95% CI 1.02–1.17) for unstable angina, and 1.05 (95% CI 1.00–1.10) for non–ST‐segment elevation acute coronary syndrome events. Excess risk from fine particulate matter air pollution exposure was not observed in patients without angiographic coronary artery disease. Conclusions Elevated fine particulate matter air pollution exposures contribute to triggering acute coronary events, especially ST‐segment elevation myocardial infarction, in those with existing seriously diseased coronary arteries but not in those with nondiseased coronary arteries.

Activation of coagulation during routine diagnostic coronary angiography

AIMS The role of anticoagulation during percutaneous coronary intervention has been well established. However, the role of anticoagulation during diagnostic coronary angiography remains unclear. Prothrombin fragment1+2 (PF1+2) and D-dimer (DD) have been reported to be useful in evaluating thrombotic phenomena. This study was designed to determine whether activation of coagulation occurs during diagnostic coronary angiography as measured by DD and PF1+2. METHODS AND RESULTS Patients not on anticoagulation (except for aspirin) and with no documented coagulopathy undergoing elective diagnostic coronary angiography were enrolled in this prospective study. Blood samples for DD and PF1+2 were obtained serially after the femoral arterial sheath was placed. Peripheral venous blood was drawn along with an initial arterial blood sample from the sheath; thereafter, arterial blood samples from the sheath were obtained every 10 minutes for a maximum of 60 minutes or until the procedure was completed or when anticoagulation was initiated. A final venous sample was drawn at the end of the procedure. The data were analysed in time interval correlation to the DD and PF1+2 level.Forty-two patients were enrolled in this study, 15 were female (35%). There were 25 (59%) patients with diabetes. The mean fluoroscopic time was 8.8+/-7.81 minutes and the average time for the procedure was 29+/-22.70 minutes. There were 192 blood samples analysed. 67% of patient completed the procedure within 20 minutes and 91% within 30 minutes. Mean venous PF1+2 level was 0.20 nmol/L at baseline and 0.39 nmol/L (p=0.06) at the final interval, while the mean arterial PF1+2 level was significantly elevated. There was an increase of 0.2 nmol/L of arterial PF1+2 every 10 minutes (p<0.001). Mean venous DD at baseline and final levels were 0.41 ug/mL and 0.45 ug/mL respectively (p=0.68). There was a significant change in arterial DD with an increase of 0.02ug/ml every 10 minutes (p=0.023). CONCLUSIONS In diagnostic coronary angiography, there is an early rise in PF1+2 levels in blood drawn through the arterial sheath suggesting that the procedure triggers local activation of coagulation that is not observed systemically. Prophylactic anticoagulation may not be necessary in stable patients without other known risk factors who will be undergoing elective diagnostic coronary angiography for less than 30 minutes. For procedures that are prolonged, or anticipated to be prolonged greater than 30 minutes, it may be advisable to administer anticoagulation to prevent thrombus formation. These findings may not be pertinent to patients with thrombophilia.

IMPACT OF TRANSITIONING FROM SPECT TO PET ON MYOCARDIAL ISCHEMIA DETECTION: EXPERIENCE FROM A HIGH VOLUME “REAL WORLD” PRACTICE

Myocardial Perfusion Imaging (MPI) with PET technology has been shown to improve ischemia detection compared to SPECT, however limited data are available comparing the modalities in clinical practice. We report the impact of transitioning from SPECT testing to PET on the ability to assess myocardial

Implementation of a cardiac PET stress program: comparison of outcomes to the preceding SPECT era

BACKGROUND Cardiac positron emission testing (PET) is more accurate than single photon emission computed tomography (SPECT) at identifying coronary artery disease (CAD); however, the 2 modalities have not been thoroughly compared in a real-world setting. We conducted a retrospective analysis of 60-day catheterization outcomes and 1-year major adverse cardiovascular events (MACE) after the transition from a SPECT- to a PET-based myocardial perfusion imaging (MPI) program. METHODS MPI patients at Intermountain Medical Center from January 2011-December 2012 (the SPECT era, n = 6,777) and January 2014-December 2015 (the PET era, n = 7,817) were studied. Outcomes studied were 60-day coronary angiography, high-grade obstructive CAD, left main/severe 3-vessel disease, revascularization, and 1-year MACE-revascularization (MACE-revasc; death, myocardial infarction [MI], or revascularization >60 days). RESULTS Patients were 64 ± 13 years old; 54% were male and 90% were of European descent; and 57% represented a screening population (no prior MI, revascularization, or CAD). During the PET era, compared with the SPECT era, a higher percentage of patients underwent coronary angiography (13.2% vs. 9.7%, P < 0.0001), had high-grade obstructive CAD (10.5% vs. 6.9%, P < 0.0001), had left main or severe 3-vessel disease (3.0% vs. 2.3%, P = 0.012), and had coronary revascularization (56.7% vs. 47.1%, P = 0.0001). Similar catheterization outcomes were seen when restricted to the screening population. There was no difference in 1-year MACE-revasc (PET [5.8%] vs. SPECT [5.3%], P = 0.31). CONCLUSIONS The PET-based MPI program resulted in improved identification of patients with high-grade obstructive CAD, as well as a larger percentage of revascularization, thus resulting in fewer patients undergoing coronary angiography without revascularization. FUNDING This observational study was funded using internal departmental funds.

MYOCARDIAL STRESS FLOWS IN OBSTRUCTIVE CAD ARE HIGHER WITH REGADENOSON THAN DIPYRIDAMOLE

Cut-off myocardial blood flow values associated with clinically significant ischemia in patients undergoing PET/CT have been reported with dipyridamole. Little is reported on MBF in stenotic vessels ≥70% as compared to non-stenotic vessels using regadenoson and Rb82. 731 patients (482 males, 65

DIFFERENCES IN CORONARY FLOW RESERVES BY GENDER AND DIABETIC STATUS AS IDENTIFIED USING CARDIAC PET/CT

Existing literature is scarce regarding normal and abnormal measurements for coronary flow reserve (CFR) non-ischemic rubidium PET/CT cardiac stress perfusion scans using regadenoson as the stress agent. Here we analyze and compare global and vessel-specific CFR between diabetics (DM) and non-