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Dive into the research topics where Stephen D. Clements is active.

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Featured researches published by Stephen D. Clements.


American Journal of Cardiology | 1988

Alterations in myocardial thallium-201 distribution in patients with chronic systemic hypertension undergoing single-photon emission computed tomography

E.Gordon DePuey; E. Guertler-Krawczynska; John V. Perkins; Wendy L. Robbins; John D. Whelchel; Stephen D. Clements

To characterize thallium-201 distribution in single-photon emission computed tomography (SPECT) cardiac images and polar bullseye maps, 100 patients with chronic systemic hypertension due to end-stage renal disease were studied and the results compared with those in 35 normotensive control subjects. Thallium-201 SPECT was performed after exercise in all control subjects and 70 hypertensive patients, and after intravenous dipyridamole in 30 patients. A frequent finding in hypertensive patients was a fixed decrease in the normal lateral-to-septal count density ratio in immediate thallium-201 SPECT images (1.02 +/- 0.10 vs 1.17 +/- 0.08 in control subjects, p less than 0.00001) and in 3-hour delayed images (1.02 +/- 0.11 vs 1.11 +/- 0.08 in control subjects, p less than 0.00001). No significant difference in count density ratio was present in patients undergoing treadmill versus diypridamole intervention. In 35 patients the count density ratio was greater than 2.0 standard deviations below the normal mean, creating the false impression of a fixed lateral defect (i.e., myocardial infarction). In 12 patients, myocardial wall thickness was measured at end-diastole by 2-dimensional echocardiography. Wall thickness was increased (greater than 11 mm) in all patients. The mean lateral-to-septal wall thickness ratio was 1.08 +/- 1.11; in no patient was the ratio less than 0.76 to indicate selective septal hypertrophy. The lateral-to-septal wall thickness and lateral-to-septal thallium-201 count density ratios correlated poorly (r = 0.43).(ABSTRACT TRUNCATED AT 250 WORDS)


American Journal of Cardiology | 1972

Diagnostic value of electrocardiographic abnormalities observed in subjects accidentally exposed to cold

Stephen D. Clements; J. Willis Hurst

Abstract Electrocardiograms were recorded in 5 patients accidentally exposed to cold. All 5 patients came from either a poorly heated room or the open air. Usually there was some alteration of mental function or ability to walk, resulting in prolonged exposure to cold. The characteristic electrocardiographic findings in hypothermia are bradycardia, atrial fibrillation, muscle tremor artifact, prolongation of the QRS complex with “J” or “Osborn” waves and prolongation of the Q-T interval. In these patients changes ranged from mild to severe. Follow-up tracings were obtained in 3. The electrocardiogram can be of considerable value in revealing hypothermic states with low “core” temperature. Severe electrocardiographic changes are easily detected and usually are associated with a grave underlying illness and poor prognosis. Milder degrees of hypothermia result in recognizable electrocardiographic changes that can be helpful in evaluating a recorded low rectal temperature.


Circulation | 2003

Twenty-Year Survival After Coronary Artery Surgery An Institutional Perspective From Emory University

William S. Weintraub; Stephen D. Clements; L. Van-Thomas Crisco; Robert A. Guyton; Joseph M. Craver; Ellis L. Jones; Charles R. Hatcher

Background—Coronary artery bypass graft (CABG) surgery has been performed frequently for symptomatic coronary atherosclerotic heart disease for more than 30 years. However, uncertainty exists regarding the relationship between long-term survival after CABG and readily available clinical correlates of mortality. Methods and Results—We studied outcome at 20 years by age, sex, and other variables in 3939 patients who had CABG surgery from 1973 to 1979 in the Emory University System of Healthcare. Twenty-year survival, freedom from myocardial infarction, and freedom from repeat CABG were 35.6% (95% confidence interval [CI], 33.9% to 37.3%), 66.6% (95% CI, 64.6% to 68.6%), and 59.1% (95% CI, 56.9% to 61.5%). Multivariate correlates of late mortality were age (hazard ratio [HR], 1.46 per 10 years), female sex (HR, 1.21), hypertension (HR, 1.44), angina class (HR, 1.07 per class increase of 1), prior CABG (HR, 1.72), ejection fraction (HR, 1.07 per 10-point decrease), number of vessels diseased (HR, 1.11 per 1-vessel increase), and weight (HR, 1.04 per 10 kg). Twenty-year survival by age was 55%, 38%, 22%, and 11% for age <50, 50 to 59, 60 to 69, and >70 years at the time of initial surgery. Survival at 20 years after surgery with and without hypertension was 27% and 41%, respectively. Similarly, 20-year survival was 37% and 29% for men and women. Conclusions—Symptomatic coronary atherosclerotic heart disease requiring surgical revascularization is progressive with continuing events and mortality. Clinical correlates of mortality significantly impact survival over time and may help identify long-term benefits after CABG.


The Annals of Thoracic Surgery | 1981

Coronary Bypass for Relief of Persistent Pain Following Acute Myocardial Infarction

Ellis L. Jones; Thad F. Waites; Joe M. Craver; James M. Bradford; John S. Douglas; Spencer B. King; David K. Bone; Edward R. Dorney; Stephen D. Clements; Tom Thompkins; Charles R. Hatcher

Between January, 1976, and April, 1980, 116 patients had urgent myocardial revascularization for clinical instability within 30 days of acute myocardial infarction (MI). Group 1 (8 patients) had coronary bypass grafting within 24 hours of acute MI; Group 2 (20 patients) had coronary bypass grafting 2 to 7 days after acute MI; and Group 3 (88 patients) had coronary bypass grafting 8 to 30 days after infarction. Indications for operation were persistent or recurrent pain (81%), pain plus ventricular arrhythmias (12%), and pain plus compelling anatomy. The incidence of single-vessel, triple-vessel, and left main coronary artery disease was 28%, 31%, and 12%, respectively. There were no hospital deaths in the series. The incidence of inotropic requirements, postoperative intraaortic balloon pumping, ventricular arrhythmias, and perioperative infarction was higher in patients operated on within 7 days of acute MI than for patients having coronary bypass grafting after this time. There have been 5 late deaths during a mean follow-up of 14 months. Actuarial survival was 97% at 18 months. Seventy-one percent of patients are presently pain free. Graft patency was 84% in 17 patients recatheterized after coronary bypass grafting and in 14 patients, grafts placed into the area of infarction were patent. This study suggests that the frequency of perioperative complications will be increased in patients operated on within one week of MI, but after this period, coronary bypass grafting can be accomplished with the same morbidity as the of elective operation.


Jacc-cardiovascular Imaging | 2014

Multimodality imaging of aortitis.

Gregory Hartlage; John Palios; Bruce J. Barron; Arthur E. Stillman; Eduardo Bossone; Stephen D. Clements; Stamatios Lerakis

Multimodality imaging of aortitis is useful for identification of acute and chronic mural changes due to inflammation, edema, and fibrosis, as well as characterization of structural luminal changes including aneurysm and stenosis or occlusion. Identification of related complications such as dissection, hematoma, ulceration, rupture, and thrombosis is also important. Imaging is often vital for obtaining specific diagnoses (i.e., Takayasu arteritis) or is used adjunctively in atypical cases (i.e., giant cell arteritis). The extent of disease is established at baseline, with associated therapeutic and prognostic implications. Imaging of aortitis may be useful for screening, routine follow up, and evaluation of treatment response in certain clinical settings. Localization of disease activity and structural abnormality is useful for guiding biopsy or surgical revascularization or repair. In this review, we discuss the available imaging modalities for diagnosis and management of the spectrum of aortitis disorders that cardiovascular physicians should be familiar with for facilitating optimal patient care.


American Journal of Cardiology | 1977

Aortic stenosis: Echocardiographic cusp separation and surgical description of aortic valve in 22 patients

Sonia Chang; Stephen D. Clements; John Chang

Diminished echocardiographic aortic cusp separation is used as one indicator of the severity of aortic stenosis. To test the validity of this index, 22 patients--12 (55 percent) with isolated aortic valve disease and 10 (45 percent) with aortic stenosis associated with mitral or coronary artery disease--underwent M mode echocardiographic examination before aortic valve replacement. Tracings of diagnostic quality were obtained without difficulty from all 22 patients. Cardiac catheterization was performed in 21 patients. Echocardiographic cusp separation was measured from the apparent mid-systolic orifice and from the outer periphery of the anterior cusp to the outer periphery of the posterior cusp (maximal peripheral cusp separation). Mid-systolic cusp separation varied in nearly every patient, depending on the angle of leaflet presentation to the ultrasonic beam. Maximal peripheral cusp separation measured 16 mm in 18 of 22 patients (82 percent); it indicated neither the severity of the aortic stenosis as documented with cardiac catheterization nor the mobility of the cusps seen at operation. The surgical and echocardiographic descriptions of leaflet and aortic root calcification were similar. In situ examination of aortic cusp separation indicated that diseased aortic valves are not comparable with normal valves or valves with uncomplicated congenital obstruction. The aortic leaflets were curled, fused, calcified and deformed from their natural state of coaptation. Abnormal thickening and limited or eccentric mobility of the aortic leaflets were useful indicators of the cause of valve disease, but cusp deformity secondary to aortic stenosis invalidated mid-systolic cusp separation and maximal peripheral cusp separation as indicators of the severity of aortic stenosis.


American Journal of Cardiology | 1991

Coronary artery surgery in octogenarians

William S. Weintraub; Stephen D. Clements; John Ware; Joseph M. Craver; Caryn L. Cohen; Ellis L. Jones; Robert A. Guyton

Abstract Coronary surgery is being performed increasingly in older patients who may have more extensive disease as well as other factors that may lead to more frequent complications and death. 1–3 Several studies have shown that the rate of complications and mortality in elderly patients are higher than in younger ones. 4–7 Advanced age has also been shown to correlate with late mortality after cardiac surgery. 8 Because of these data, there has been uncertainty as to use of cardiac surgery in older patients, especially in those aged ≥80 years. This report presents results of coronary artery bypass grafting both in hospital and at follow-up in patients aged ≥80.


Journal of Cardiovascular Magnetic Resonance | 2014

The role of cardiovascular magnetic resonance in stratifying paravalvular leak severity after transcatheter aortic valve replacement: an observational outcome study

Gregory Hartlage; Vasilis Babaliaros; Vinod H. Thourani; Salim Hayek; Christina Chrysohoou; Nima Ghasemzadeh; Arthur E. Stillman; Stephen D. Clements; John N. Oshinski; Stamatios Lerakis

BackgroundSignificant paravalvular leak (PVL) after transcatheter aortic valve replacement (TAVR) confers a worse prognosis. Symptoms related to significant PVL may be difficult to differentiate from those related to other causes of heart failure. Cardiovascular magnetic resonance (CMR) directly quantifies valvular regurgitation, but has not been extensively studied in symptomatic post-TAVR patients.MethodsCMR was compared to qualitative (QE) and semi-quantitative echocardiography (SQE) for classifying PVL and prognostic value at one year post-imaging in 23 symptomatic post-TAVR patients. The primary outcome was a composite of all-cause death, heart failure hospitalization, and intractable symptoms necessitating repeat invasive therapy; the secondary outcome was a composite of all-cause death and heart failure hospitalization. The difference in event-free survival according to greater than mild PVL versus mild or less PVL by QE, SQE, and CMR were evaluated by Kaplan-Meier survival analysis.ResultsCompared to QE, CMR reclassified PVL severity in 48% of patients, with most patients (31%) reclassified to at least one grade higher. Compared to SQE, CMR reclassified PVL severity in 57% of patients, all being reclassified to at least one grade lower; SQE overestimated PVL severity (mean grade 2.5 versus 1.7, p = 0.001). The primary and secondary outcomes occurred in 48% and 35% of patients, respectively. Greater than mild PVL by CMR was associated with reduced event-free survival for the primary outcome (p < 0.0001), however greater than mild PVL by QE and SQE were not (p = 0.83 and p = 0.068). Greater than mild PVL by CMR was associated with reduced event-free survival for the secondary outcome, as well (p = 0.012).ConclusionIn symptomatic post-TAVR patients, CMR commonly reclassifies PVL grade compared with QE and SQE. CMR provides superior prognostic value compared to QE and SQE, as patients with greater than mild PVL by CMR (RF > 20%) had a higher incidence of adverse events.


American Journal of Cardiology | 1976

Myotonia dystrophica: Ventricular arrhythmias, intraventricular conduction abnormalities, atrioventricular block and Stokes-Adams attacks successfully treated with permanent transvenous pacemaker

Stephen D. Clements; Rudolf A. Colmers; J. Willis Hurst

In a patient with myotonia dystrophica multiple ventricular arrhythmias and high degree atrioventricular block requiring a permanent pacemaker developed. Patients with skeletal muscle disease may present with disproportionately advanced manifestations of associated cardiac disease. Early recognition of potential serious underlying cardiac disease is important in patients with this condition.


Ophthalmology | 1991

Lack of Association Between Keratoconus, Mitral Valve Prolapse, and Joint Hypermobility

Debra A. Street; Eric T. Vinokur; George O. Waring; Scott J. Pollak; Stephen D. Clements; John V. Perkins

The authors enrolled 95 patients with keratoconus and 96 matched controls in a cross-sectional study to determine if mitral valve prolapse and hypermobile joints occur with greater frequency in individuals with keratoconus than in individuals without keratoconus. The hypothesis that keratoconus may not be a distinct eye disease, but a nonspecific sign representing a more generalized systemic disorder, possibly a mild collagen tissue abnormality, was considered. M-mode and two dimensional echocardiography and cardiac auscultation detected no statistically significant difference in the prevalence of mitral valve prolapse in patients with keratoconus compared with controls. Formal, systematic examination of five joints also failed to detect a statistically significant difference in the prevalence of hypermobile joints in keratoconus patients and controls. However, as an ancillary finding, a significantly higher proportion of patients with keratoconus was found to have a history of hay fever than was the case with controls.

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Gregory Hartlage

University of South Florida

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Riyaz S. Patel

University College London

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