Arthur J. Roberts

Prevalence of Metabolic Syndrome in Retired National Football League Players

The National Institute of Occupational Safety and Health mortality study of National Football League (NFL) players concluded that retired NFL linemen have an increased risk of cardiovascular death compared with both nonlinemen and the general population. Though elevated body mass index contributed to the increased cardiac risk of linemen, it could not fully account for the mortality observed, suggesting that other unmeasured cardiovascular risk factors were involved. We performed a cross-sectional prevalence study of metabolic syndrome (MS), and its individual component criteria, in 510 retired NFL players who were recruited to multicity health screenings from February 2004 through June 2006. The International Diabetes Federation criteria were used to define MS. The MS component criteria of body mass index>30 kg/m2, reduced high-density lipoprotein, and raised fasting glucose were more prevalent in linemen compared with nonlinemen (85.4% vs 50.3%, p<0.001; 42.1% vs 32.7%, p=0.04; 60.4% vs 37.6%, p<0.001, respectively). Metabolic syndrome was more prevalent in linemen compared with nonlinemen (59.8% vs 30.1%, p<0.001). In conclusion, linemen exhibited a high prevalence of MS, almost double the prevalence of their nonlinemen counterparts. These findings may partially explain the increased risk for cardiovascular death observed in retired linemen and could have significant public health implications for preprofessional training regimens and postprofessional health maintenance.

Clinical Evaluation of the Relative Effectiveness of Multidose Crystalloid and Cold Blood Potassium Cardioplegia in Coronary Artery Bypass Graft Surgery: A Nonrandomized Matched-Pair Analysis

Controversy exists concerning the most effective method of myocardial protection during coronary artery bypass graft operations. Accordingly, we performed a matched-pair analysis between 25 patients receiving multidose hypothermic potassium crystalloid cardioplegia and 25 other patients receiving cold blood potassium cardioplegia. Patients were matched on the basis of preoperative ejection fraction (EF) and the number of anatomically similar stenotic coronary arteries. The adequacy of myocardial protection was assessed by serial perioperative determinations of radionuclide ventriculography, hemodynamic measurements, analyses of electrocardiograms and serum levels of MB-CK. We found that the level of myocardial protection was similar between unstratified groups. However, when subgroups were selected on the basis of prolonged aortic cross-clamp time (greater than ninety minutes) or impaired preoperative left ventricular function (EF less than 40%), there was a suggestion that cold blood cardioplegia may be advantageous.

Comparison of National Football League Linemen Versus Nonlinemen of Left Ventricular Mass and Left Atrial Size

Retired National Football League (NFL) linemen have higher cardiovascular mortality compared with nonlinemen. We examined echocardiographic characteristics of retired NFL linemen compared with nonlinemen to determine if position-dependent cardiac remodeling resulted in increased left ventricular (LV) mass and left atrial (LA) size. We performed echocardiography in 487 retired NFL football players. Demographic, medical, and professional career information was collected. Interventricular septal and posterior wall thickness, LV end diastolic diameter, and LA area were measured. Body mass index (BMI) and LV mass were calculated. Retired linemen had significantly higher LV mass (234.8 +/- 65.8 g) than nonlinemen (199.8 +/- 55.4 g, p <0.0001). LA area was higher in linemen versus nonlinemen (22.5 vs 20.1 cm(2), p <0.0001). Independent predictors of increased LV mass were BMI (p <0.003), linemen position (p <0.024), and systolic blood pressure (p <0.005). In former players with BMI <35 kg/m(2) there was a difference between linemen and nonlinemen in LV mass (219.9 +/- 44.3 vs 182.6 +/- 44.3 g, p = 0.004) and LV mass/height (114.3 +/- 23.5 vs 98.8 +/- 25.2 g/m, p = 0.005). In former players with BMI >35 kg/m(2), there was no difference. There was no difference in LA area between linemen and nonlinemen in both BMI groups. In conclusion, LV mass and LA area size were highest in retired linemen. Player BMI, position, and systolic blood pressure were significant predictors of LV mass. In retired linemen compared with retired nonlinemen, the persistence of these cardiac adaptations may contribute to the higher cardiovascular mortality seen in retired linemen.

Comparative effects of nitroglycerin and nitroprusside on prostacyclin generation in adult human vessel wall.

The precise mechanism of vasodilatory actions of nitroso-compounds is not clear. It has been suggested that these drugs might modulate release of the vasodilator, prostacyclin, from cultured endothelial cells and bovine arteries or potentiate actions of prostacyclin. This study was designed to examine the effects of nitroglycerin and nitroprusside on prostacyclin release from adult human vasculature. Saphenous vein ring preparations were incubated with nitroglycerin or nitroprusside and arachidonic acid, the substrate for prostacyclin. Vascular rings incubated with nitroglycerin released significantly more prostacyclin (measured as 6-keto-prostaglandin F1 alpha, a stable hydrolysis product of prostacyclin by radioimmunoassay) compared with the control vascular rings (p less than 0.02). This increase was observed at the therapeutic concentrations of nitroglycerin (5 to 10 ng/ml). However, incubation of saphenous vein rings with nitroprusside in concentrations as high as 1 microgram/ml was not associated with any increase in prostacyclin release. Prior incubation of vascular rings with the cyclooxygenase blocker, indomethacin, inhibited nitroglycerin-induced prostacyclin release. Incubation of vascular rings with the selective thromboxane A2 blocker, OKY 1581, resulted in additional prostacyclin release with nitroglycerin treatment, presumably by inhibiting vessel wall-generated thromboxane A2. Nitroprusside had no significant effect on prostacyclin release from indomethacin-treated or OKY 1581-treated vascular rings. This study suggests significant stimulatory effects of nitroglycerin, but not of nitroprusside, on prostacyclin release from human saphenous vein. Nitroglycerin-induced prostacyclin release may be an important mechanism of its antiischemic actions in human subjects.

Incidence of subclinical atherosclerosis as a marker of cardiovascular risk in retired professional football players.

The purpose of this study was to evaluate subclinical atherosclerosis in retired professional football players. Two hundred one healthy former professional football players (mean age 50.8 years; mean body mass index 31.5 kg/m(2)) were screened for the prevalence of cardiovascular risk factors, metabolic syndrome, and subclinical atherosclerosis by carotid artery ultrasound and compared with a cohort of men of similar body mass index referred for the assessment of subclinical atherosclerosis by carotid ultrasound. The prevalence of carotid artery plaque in the players was not significantly different from that of the body mass index-matched patients (33.3% vs 29.3%, p = 0.45). For the 2 groups, the prevalence of carotid artery plaque was >3 times higher than that reported in general population studies of patients with the same age range, gender, and exclusions. Metabolic syndrome prevalence was higher in linemen than in nonlinemen (45.8% vs 22.5%, p = 0.001), but there was no statistical difference in plaque presence between linemen and nonlinemen (27.1% vs 35.9%, p = 0.23). In conclusion, despite their elite athletic histories, former professional football players have a similar prevalence of advanced subclinical atherosclerosis as a clinically referred population of overweight and obese men.

Hazardous placement of a Robertshaw-type endobronchial tube.

Operations on the thoracic aorta may be facilitated by inserting an endobronchial tube to improve exposure of the thoracic aorta so that the left lung can be collapsed while the right lung is ventilated (1,2). Because right endobronchial intubation could compromise ventilation to the upper lobe of the right lung, we selected a Robertshaw-type left double-lumen endobronchial tube for a patient who required repair of a descending thoracic aortic aneurysm.

Emergency Coronary Artery Bypass Graft Surgery for Threatened Acute Myocardial Infarction Related to Coronary Artery Catheterization

In 20 patients undergoing cardiac catheterization, usually involving balloon-catheter dilation or streptokinase infusion, catheter-induced coronary artery intimal damage resulted in severe chest pain, electrocardiographic evidence of obstruction or dissection of a major coronary artery. These patients were surgically revascularized within 8 hours after the onset of the acute chest pain syndrome. Our experience with pharmacological and catheter-related manipulations to improve coronary blood flow after the ischemic episode but before operation suggested that the additional time spent in the catheterization laboratory was worthwhile. The injured coronary artery was the left anterior descending in 10 patients, the right in 8, the left main in 1 patient, and an obtuse marginal branch of the circumflex in 1. The average number of grafts per patient was 2.5; only 6 patients had single bypass grafts. In 5 patients, intraaortic balloon pumping was used either preoperatively or postoperatively. Inotropic support was used postoperatively in 5 patients, and 7 patients received lidocaine for ventricular irritability. Abnormal elevation of the serum isoenzyme of creatine kinase (CK-MB) was seen in 8 patients, and new Q waves were noted in 4 patients; 3 of these 4 patients with new Q waves also had abnormal serum CK-MB levels. Global ejection fraction obtained by the equilibrium-gated blood pool scan postoperatively was 60 +/- 3%, which was similar to the 62 +/- 3% obtained from the contrast-determined ventriculogram done preoperatively prior to the catheter-related injury. There were no early or late deaths, but morbidity was much higher in the group who had emergency coronary artery bypass grafting (CABG) compared with those who had elective CABG.(ABSTRACT TRUNCATED AT 250 WORDS)

Relative Efficacy of Left Ventricular Venting and Venous Drainage Techniques Commonly Used during Coronary Artery Bypass Graft Surgery

Sixty patients with symptomatic coronary artery disease undergoing coronary artery bypass graft operation were prospectively randomized into one of six equal groups based on the intraoperative method of left ventricular venting and venous drainage. Group 1 had bicaval venous drainage without snaring and left ventricular venting through the superior pulmonary vein; Group 2, two-stage venous drainage and venting as in Group 1; Group 3, bicaval venous drainage without snaring and no left ventricular vent; Group 4, two-stage venous drainage and no left ventricular vent; Group 5, bicaval venous drainage without snaring and with ascending aortic venting through a catheter; and Group 6, two-stage venous drainage and venting as in Group 5. Left ventricular performance was determined by radionuclide ventriculography from which global ejection fraction and regional wall motion were determined. Cardiac output was obtained by the thermodilution technique. Myocardial temperature was assessed by a needle thermistor during aortic cross-clamping. Serial electrocardiograms and levels of myocardial-specific isoenzymes (serum CPK-MB) were also analyzed. Each of the techniques tested was equally effective as determined by an analysis of intraoperative myocardial cooling and postoperative hemodynamic profiles, radionuclide ventriculography, and ECG or enzymatic evidence of myocardial damage. However, we maintain that this conclusion is valid only if adequate ventricular decompression is provided intraoperatively.

Association between traditional cholesterol parameters, lipoprotein particle concentration, novel biomarkers and carotid plaques in retired National Football League players

OBJECTIVES We assessed whether low-density lipoprotein particle concentration (LDL-P) and high-sensitivity C-reactive protein [hs-CRP] can identify subclinical atherosclerosis better than traditional cholesterol parameters in retired National Football League (NFL) players. BACKGROUND It is not known whether LDL-P and the biomarker hs-CRP can identify subclinical atherosclerosis better than low-density lipoprotein cholesterol (LDL-C) or non-high-density-lipoprotein cholesterol (non-HDL-C) in retired NFL players, given high prevalence of metabolic syndrome in these players. METHODS Carotid artery plaque screening was performed with traditional lipids, LDL-P, and hs-CRP in 996 retired players. Logistic regression analyses comparing highest with the lowest quartile were performed. RESULTS Carotid artery plaques were seen in 41%. LDL-C (odds ratio [OR] 1.66, 95% confidence interval [CI] 1.06-2.59), non-HDL-C (OR 1.67, 95% CI 1.04-2.67), and LDL-P (OR 2.21, 95% CI 1.35-3.62) were associated with plaques in adjusted models. Among 187 retired players with metabolic syndrome, LDL-C (OR 1.40, 95% CI 0.53-3.72) was not associated with carotid plaques, whereas LDL-P (OR 3.71, 95% CI 1.16-11.84) and non-HDL-C (OR 2.63, 95% CI 0.91-7.63, p=0.07; borderline significant) were associated with carotid plaques. hs-CRP (OR 1.13, 95% CI 0.71-1.79) was not associated with carotid plaques. CONCLUSION Carotid artery plaques were common in retired NFL players and were strongly associated with LDL-P, especially among those with metabolic syndrome. hs-CRP was not associated with carotid plaques in this cohort.

Cardiovascular Risk Factors and Coronary Atherosclerosis in Retired National Football League Players

A high prevalence of obesity exists in National Football League (NFL) players as determined by body mass index (BMI). It is not established whether increased BMI is associated with a greater prevalence of cardiovascular (CV) risk factors or coronary atherosclerosis in former NFL players than in nonathletes. This study compared CV risk factors and coronary atherosclerosis in retired NFL players to 2 groups of community controls, the population-based Dallas Heart Study and the preventive medicine cohort, the Aerobics Center Longitudinal Study. Retired NFL players (n = 201) were matched for ethnicity, age, and BMI (Aerobics Center Longitudinal Study, age only). CV risk factors were assessed by survey and screening visit. Coronary atherosclerosis was measured by computed tomography as coronary artery calcium (CAC). Compared to population-based controls, retired NFL players had a significantly lower prevalence of diabetes, hypertension, sedentary lifestyle, and metabolic syndrome, yet a higher prevalence of impaired fasting glucose and hyperlipidemia. However, there was no significant difference in the prevalence of detectable CAC (46% vs 48.3%, p = 0.69) or distribution of CAC (0 to 10, 10 to 100, 100 to 400, > or =400, p = 0.11). Comparing retired NFL players to the physically active preventive medicine controls, there was no difference in the amount of CAC. In retired NFL players, age and hyperlipidemia, not body size, were the most significant predictors of CAC. In conclusion, despite their large body size, retired NFL players do not have a greater prevalence of CV risk factors or amount of CAC than community controls.