C

Christopher G. Scott

Mayo Clinic in Florida

ORCID: 0000-0003-1340-0647

Publishes on Cardiovascular Function and Risk Factors, Cardiac Valve Diseases and Treatments, Digital Radiography and Breast Imaging. 763 papers and 33k citations.

763Publications
33kTotal Citations

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Quantitative Determinants of the Outcome of Asymptomatic Mitral Regurgitation
Cited by 1.1kOpen Access

BACKGROUND: The clinical outcome of asymptomatic mitral regurgitation is poorly defined, and the treatment is uncertain. We studied the effect on the outcome of quantifying mitral regurgitation according to recent guidelines. METHODS: We prospectively enrolled 456 patients (mean [+/-SD] age, 63+/-14 years; 63 percent men; ejection fraction, 70+/-8 percent) with asymptomatic organic mitral regurgitation, quantified according to current recommendations (regurgitant volume, 66+/-40 ml per beat; effective regurgitant orifice, 40+/-27 mm2). RESULTS: The estimated five-year rates (+/-SE) of death from any cause, death from cardiac causes, and cardiac events (death from cardiac causes, heart failure, or new atrial fibrillation) with medical management were 22+/-3 percent, 14+/-3 percent, and 33+/-3 percent, respectively. Independent determinants of survival were increasing age, the presence of diabetes, and increasing effective regurgitant orifice (adjusted risk ratio per 10-mm2 increment, 1.18; 95 percent confidence interval, 1.06 to 1.30; P<0.01), the predictive power of which superseded all other qualitative and quantitative measures of regurgitation. Patients with an effective regurgitant orifice of at least 40 mm2 had a five-year survival rate that was lower than expected on the basis of U.S. Census data (58+/-9 percent vs. 78 percent, P=0.03). As compared with patients with a regurgitant orifice of less than 20 mm2, those with an orifice of at least 40 mm2 had an increased risk of death from any cause (adjusted risk ratio, 2.90; 95 percent confidence interval, 1.33 to 6.32; P<0.01), death from cardiac causes (adjusted risk ratio, 5.21; 95 percent confidence interval, 1.98 to 14.40; P<0.01), and cardiac events (adjusted risk ratio, 5.66; 95 percent confidence interval, 3.07 to 10.56; P<0.01). Cardiac surgery was ultimately performed in 232 patients and was independently associated with improved survival (adjusted risk ratio, 0.28; 95 percent confidence interval, 0.14 to 0.55; P<0.01). CONCLUSIONS: Quantitative grading of mitral regurgitation is a powerful predictor of the clinical outcome of asymptomatic mitral regurgitation. Patients with an effective regurgitant orifice of at least 40 mm2 should promptly be considered for cardiac surgery.

Outcome of 622 Adults With Asymptomatic, Hemodynamically Significant Aortic Stenosis During Prolonged Follow-Up
Cited by 853

BACKGROUND: This study assessed the long-term outcome of a large, asymptomatic population with hemodynamically significant aortic stenosis (AS). METHODS AND RESULTS: We identified 622 patients with isolated, asymptomatic AS and peak systolic velocity > or =4 m/s by Doppler echocardiography who did not undergo surgery at the initial evaluation and obtained follow-up (5.4+/-4.0 years) in all. Mean age (+/-SD) was 72+/-11 years; there were 384 (62%) men. The probability of remaining free of cardiac symptoms while unoperated was 82%, 67%, and 33% at 1, 2, and 5 years, respectively. Aortic valve area and left ventricular hypertrophy predicted symptom development. During follow-up, 352 (57%) patients were referred for aortic valve surgery and 265 (43%) patients died, including cardiac death in 117 (19%). The 1-, 2-, and 5-year probabilities of remaining free of surgery or cardiac death were 80%, 63%, and 25%, respectively. Multivariate predictors of all-cause mortality were age (hazard ratio [HR], 1.05; P<0.0001), chronic renal failure (HR, 2.41; P=0.004), inactivity (HR, 2.00; P=0.001), and aortic valve velocity (HR, 1.46; P=0.03). Sudden death without preceding symptoms occurred in 11 (4.1%) of 270 unoperated patients. Patients with peak velocity > or =4.5 m/s had a higher likelihood of developing symptoms (relative risk, 1.34) or having surgery or cardiac death (relative risk, 1.48). CONCLUSIONS: Most patients with asymptomatic, hemodynamically significant AS will develop symptoms within 5 years. Sudden death occurs in approximately 1%/y. Age, chronic renal failure, inactivity, and aortic valve velocity are independently predictive of all-cause mortality.

Resistance Exercise in Men Receiving Androgen Deprivation Therapy for Prostate Cancer
Roanne Segal, Robert D. Reid, Kerry S. Courneya et al.|Journal of Clinical Oncology|2003
Cited by 782

PURPOSE: Androgen deprivation therapy is a common treatment in men with prostate cancer that may cause fatigue, functional decline, increased body fatness, and loss of lean body tissue. These physical changes can negatively affect health-related quality of life. Resistance exercise may help to counter some of these side effects by reducing fatigue, elevating mood, building muscle mass, and reducing body fat. METHODS: In a two-site study, 155 men with prostate cancer who were scheduled to receive androgen deprivation therapy for at least 3 months after recruitment were randomly assigned to an intervention group that participated in a resistance exercise program three times per week for 12 weeks (82 men) or to a waiting list control group (73 men). The primary outcomes were fatigue and disease-specific quality of life as assessed by self-reported questionnaires after 12 weeks. Secondary outcomes were muscular fitness and body composition. RESULTS: Men assigned to resistance exercise had less interference from fatigue on activities of daily living (P =.002) and higher quality of life (P =.001) than men in the control group. Men in the intervention group demonstrated higher levels of upper body (P =.009) and lower body (P <.001) muscular fitness than men in the control group. The 12-week resistance exercise intervention did not improve body composition as measured by changes in body weight, body mass index, waist circumference, or subcutaneous skinfolds. CONCLUSION: Resistance exercise reduces fatigue and improves quality of life and muscular fitness in men with prostate cancer receiving androgen deprivation therapy. This form of exercise can be an important component of supportive care for these patients.