Kevin P. Cohoon

Long-term clinical outcomes of real-world experience using sirolimus-eluting stents in saphenous vein graft disease

Objective: To evaluate the long‐term clinical outcomes of patients undergoing percutaneous coronary intervention for saphenous vein graft (SVG) disease. Specifically, we compared clinical endpoints of patients who received sirolimus‐eluting stents (SES) versus bare‐metal stents (BMS) for SVG disease. Background: A recent small randomized‐controlled trial (RCT) reported increased mortality with the use of SES in SVG disease. Methods: We retrospectively identified patients who underwent SES placement for a SVG lesion(s) at our institutions over a 4‐year period. The procedural and medical records were reviewed to identify predetermined clinical outcomes. Results: 318 patients who underwent SES placement for a SVG lesion were identified. 7 patients were lost to follow‐up. 141/311 patients (45%) received SES, while 170/311 (55%) received BMS. At a mean follow‐up of 34 months, there was a reduction in target lesion revascularization (TLR) (7% vs. 14%, P = 0.07) without an increased risk of mortality (6% vs. 12%, P = 0.06) in patients who received SES compared to patients who received BMS. When compared to the recent RCTs SES patients at long‐term follow‐up, our SES patients had significantly less mortality; rates of myocardial infarction, TLR, target vessel revascularization, and major adverse cardiac events; and were more likely to be taking dual antiplatelet and statin medications. Conclusion: Our results support that SES used in SVG lesions result in a reduction in TLR without an increased risk of mortality, and therefore may be an equally safe and feasible technique for revascularization with excellent long‐term clinical outcomes. These patients may benefit from prolonged dual antiplatelet and statin medication regimens.

Abdominal Aortic Calcium, Coronary Artery Calcium, and Cardiovascular Morbidity and Mortality in the Multi-Ethnic Study of Atherosclerosis

Objective—To evaluate the predictive value of abdominal aortic calcium (AAC) for incident cardiovascular disease (CVD) independent of coronary artery calcium (CAC). Approach and Results—We evaluated the association of AAC with CVD in 1974 men and women aged 45 to 84 years randomly selected from the Multi-Ethnic Study of Atherosclerosis participants who had complete AAC and CAC data from computed tomographic scans. AAC and CAC were each divided into following 3 percentile categories: 0 to 50th, 51st to 75th, and 76th to 100th. During a mean of 5.5 years of follow-up, there were 50 hard coronary heart disease events, 83 hard CVD events, 30 fatal CVD events, and 105 total deaths. In multivariable-adjusted Cox models including both AAC and CAC, comparing the fourth quartile with the ⩽50th percentile, AAC and CAC were each significantly and independently predictive of hard coronary heart disease and hard CVD, with hazard ratios ranging from 2.4 to 4.4. For CVD mortality, the hazard ratio was highly significant for the fourth quartile of AAC, 5.9 (P=0.01), whereas the association for the fourth quartile of CAC (hazard ratio, 2.1) was not significant. For total mortality, the fourth quartile hazard ratio for AAC was 2.7 (P=0.001), and for CAC, it was 1.9, P=0.04. Area under the receiver operating characteristic curve analyses showed improvement for both AAC and CAC separately, although improvement was greater with CAC for hard coronary heart disease and hard CVD, and greater with AAC for CVD mortality and total mortality. Sensitivity analyses defining AAC and CAC as continuous variables mirrored these results. Conclusions—AAC and CAC predicted hard coronary heart disease and hard CVD events independent of one another. Only AAC was independently related to CVD mortality, and AAC showed a stronger association than CAC with total mortality.

Mapping the global geographic potential of Zika virus spread

The Americas are presently experiencing the most serious known outbreak of Zika virus (ZIKV). Here, we present a novel set of analyses using environmental characteristics, vector mosquito distributions, and socioeconomic risk factors to develop the first map to detail global ZIKV transmission risk in multiple dimensions based on ecological niche models. Our model predictions were tested against independent evaluation data sets, and all models had predictive ability significantly better than random expectations. The study addresses urgent knowledge gaps regarding (1) the potential geographic scope of the current ZIKV epidemic, (2) the global potential for spread of ZIKV, and (3) drivers of ZIKV transmission. Our analysis of potential drivers of ZIKV distributions globally identified areas vulnerable in terms of some drivers, but not for others. The results of these analyses can guide regional education and preparedness efforts, such that medical personnel will be better prepared for diagnosis of potential ZIKV cases as they appear.

Discordant Diagnosis of Lower Extremity Peripheral Artery Disease Using American Heart Association Postexercise Guidelines

Abstract To determine whether postexercise criteria for peripheral artery disease (PAD) diagnosis recommended by the American Heart Association (AHA) identifies the same group of PAD patients. Diagnosis of PAD is performed using ankle-brachial index at rest (resting-ABI). When resting-ABI is not contributive, an AHA scientific statement recommend to use 1 of 2 following criteria: a postexercise ABI decrease of greater than 20% or a postexercise ankle pressure decrease of greater than 30 mm Hg. Between 1996 and 2012, 31,663 consecutive patients underwent lower-extremity arterial study at Mayo Clinic. Among them, only unique patients who had exercise treadmill testing were analyzed. In this retrospective analysis, resting-ABI, postexercise ABI, and postexercise decrease of ankle pressure measured at 1-minute were measured in each patient. We conducted an analysis of agreement between postexercise criteria expressing the agreement separately for the positive and the negative ratings. Twelve thousand three hundred twelve consecutive patients were studied with a mean age of 67 ± 12 years, 61% male. According to resting-ABI, 4317 (35%) patients had PAD. In the whole population, if a clinician diagnoses “PAD” with 1 postexercise criterion, the probability that other clinicians would also diagnose “PAD” is 74.3%. If a clinician diagnoses “no PAD”, the probability that other clinicians would also diagnose “no PAD” is 82.4%. In the patients to be of potential benefit from treadmill test when the resting-ABI > 0.90, if a clinician diagnoses “PAD” with 1 postexercise criterion, the probability that other clinicians would also diagnose “PAD” is 58.4% whereas if a clinician diagnoses “no PAD,” the probability that other clinicians would also diagnose “no PAD” is 87.5%. Postexercise criteria do not identify the same group of PAD patients. In our opinion, postexercise criteria to define PAD deserve additional study.

Inherited and Secondary Thrombophilia

Case Presentation 1: A healthy 19-year-old man presented with new chest pain and near syncope. Computed tomography pulmonary angiography showed a saddle pulmonary embolus. The patient denied recent travel, trauma, surgery, or hospitalization. His mother had 2 miscarriages at 10 weeks of gestation, and his maternal grandfather had deep venous thrombosis at 60 years of age. Case Presentation 2: A healthy 45-year-old woman reported new dyspnea and left calf pain. Computed tomography pulmonary angiography and compression venous duplex ultrasonography showed bilateral pulmonary emboli and acute left leg deep vein thrombosis, respectively. The patient denied exogenous hormone use, recent travel, trauma, surgery, or hospitalization. Her health maintenance was current, and she gave a family history of pernicious anemia, Grave disease, and amyotrophic lateral sclerosis. Laboratory analyses showed reduced hemoglobin (11.4 g/dL; normal, 12.0–15.5 g/dL), increased red blood cell distribution width (18.9%; normal, 11.9%–15.5%), and mild thrombocytopenia. Neither patient had previous venous thromboembolism, and both were referred to the Mayo Clinic Thrombophilia Center for apparent idiopathic venous thromboembolism. Thrombophilia is defined as a predisposition (susceptibility) to thrombosis. Thrombophilia is not a disease per se, but may be associated with a disease (eg, cancer), drug exposure (eg, oral contraceptives) or condition (eg, pregnancy or postpartum, secondary thrombophilia; Table 1), and thrombophilia may be inherited (Table 2).1 This concept is important because disease susceptibility does not imply an absolute requirement for primary or secondary prevention, or for treatment. Most persons with a thrombophilia do not develop thrombosis. Thus, thrombophilia must be considered in the context of other risk factors for incident thrombosis, or predictors of recurrent thrombosis, when estimating the need for primary or secondary prophylaxis, respectively. View this table: Table 1. Secondary Thrombophilia1 View this table: Table 2. Inherited Thrombophilia1 The role of special coagulation testing for an acquired or inherited thrombophilia is controversial. Thrombophilia testing should only be done if …

Are myocardial infarction and venous thromboembolism associated? Population-based case–control and cohort studies

INTRODUCTION Because the association of myocardial infarction (MI) and venous thromboembolism (VTE) is uncertain, we tested MI as a VTE risk factor and VTE as a predictor of MI. MATERIALS AND METHODS Using Rochester Epidemiology Project resources, we identified all Olmsted County, MN residents with objectively-diagnosed incident VTE over the 13-year period, 1988-2000 (n=1311), one to two resident controls per VTE case (n=1511), and all residents with incident MI over the 31-year period, 1979-2010. For VTE cases and controls, we reviewed their complete medical records in the community for VTE and MI risk factors. Using conditional logistic regression we tested MI as a potential VTE risk factor, both unadjusted and after adjusting for VTE risk factors. We also followed VTE cases and controls without prior MI forward in time for incident MI through 12/31/2010, and using Cox proportional hazards modeling, tested VTE as a predictor of MI, both unadjusted and after adjusting for MI risk factors. RESULTS The number (%) of MI prior to VTE among cases and controls were 75 (5.7) and 51 (3.4), respectively, and the number (%) of MI after VTE among cases and controls were 58 (4.4) and 77 (5.1), respectively. In univariate analyses, MI was significantly associated with VTE but not after adjusting for VTE risk factors. In both univariate and multivariate analyses, VTE (overall or idiopathic) was not a predictor of MI. CONCLUSIONS MI is not an independent risk factor for VTE, and VTE is not a predictor of MI.

RIVAROXABAN COMPARED TO LOW MOLECULAR WEIGHT HEPARIN IN TREATMENT OF MALIGNANCY ASSOCIATED VENOUS THROMBOEMBOLISM

Low molecular weight heparin (LMWH) is the guideline endorsed treatment of choice for cancer associated venous thromboembolism (VTE). Rivaroxaban offers a convenient potential alternative to LMWH; however there are no data comparing either the efficacy or safety of these two therapies in this

Retrievable inferior vena cava filters can be placed and removed with a high degree of success: Initial experience.

Evaluate the success rate of retrievable inferior vena cava filter (IVC) removal in a tertiary care practice.

The impact of gender and left atrial blood stasis on adiponectin levels in non-valvular atrial fibrillation

BACKGROUND Obesity is a risk factor for non-valvular atrial fibrillation (NVAF), diabetes mellitus, and hypertension. Adiponectin, a unique biomarker of adipose tissue, has antiinflammatory, insulin-sensitizing, and antiatherogenic properties and is known to be higher in women. The relationship between adiponectin, gender, and thromboembolic risk in atrial fibrillation however is unknown. METHODS The relationship between gender, adiponectin levels, and echocardiographic measures of blood stagnation and left atrial appendage thrombus (LAAT) was assessed in 209 patients with NVAF (55 women and 154 men; mean age 63 ± 14 years) compared to 70 normal sinus rhythm controls (29 women and 41 men; mean age 64 ± 14 years). Total adiponectin was measured by solid-phase ELISA. Demographic and clinical variables of CHADS2 and CHA2DS2-VASc were collected, and spontaneous echocardiographic contrast (SEC), left atrial appendage emptying velocity (LAAEV) and left atrium volume index (LAVI) were measured prospectively. RESULTS Elevated adiponectin was associated with advanced cardiovascular pathology and permanent arrhythmia but only in men with NVAF. In NVAF men, a step-wise increase in adiponectin levels was noted relative to increasing intensity of SEC and decreasing LAAEV. Adiponectin level >16657 ng/ml predicted LAAT (OR: 3.66; 95% Cl: 1.21-11.48; p=0.022) after adjustment for CHADS2 score in men but not in women with NVAF. CONCLUSIONS There is a direct correlation between elevated adiponectin level and the degree of left atrial blood stasis in men but not in women with NVAF. High adiponectin levels can be used as an important variable in the prediction of LAAT.

Should platelet function testing guide antiplatelet therapy for patients with coronary artery stenting or acute coronary syndromes

Inhibition of platelet activation (“antiplatelet therapy”) with platelet P2Y12 (ADP) receptor antagonists (i.e., thienopyridines such as clopidogrel and prasugrel) reduces platelet-rich thrombi that cause coronary artery stent thrombosis and recurrent acute coronary syndrome (ACS)3 (i.e., unstable angina pectoris and myocardial infarction). However, several reports suggest that there are large interindividual variations in platelet inhibition by clopidogrel, with up to one-third of patients having apparently “high platelet reactivity” while on therapy; these patients may be at increased risk for stent thrombosis and recurrent ACS (1). Consequently, platelet function testing may identify patients in whom adjustment of thienopyridine therapy is warranted to minimize the risk of both ischemic and bleeding complications. The introduction of point-of-care devices has made it possible to consider the routine evaluation of on-treatment platelet reactivity in patients undergoing coronary stenting and in ACS patients. Platelet function testing has been used in the research setting to individualize dosing of thienopyridine therapy in patients undergoing percutaneous intervention (PCI) with or without stent placement and in ACS patients (1). Several platelet function assays are available, including light transmission aggregometry (LTA), vasodilator-stimulated …