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Martin St John Sutton

Publications and source records attributed to Martin St John Sutton.

At least 19 recordsLinked to original sources
PubMed2006

Cardiovascular risk factors in hypertension: rationale and design of studies to investigate the effects of controlled-release carvedilol on regression of left ventricular hypertrophy and lipid profile.

Patients at high risk for hypertension may require several therapeutic agents to lower their blood pressure to guideline-recommended targets. Some antihypertensive agents are more effective than others in protecting against cardiovascular morbidity and mortality. Numerous beta-blocking agents have been approved by the US Food and Drug Administration (FDA) for the treatment of hypertension. Previous trials have demonstrated that although all beta-blockers effectively reduce blood pressure, there are differences in how they affect various metabolic factors. In 2 trials, a novel controlled-release (CR) formulation of carvedilol will be tested against other selective beta-blockers to determine whether differences exist in their individual effects on cardiovascular risk factors. These will be the first head-to-head trials using carvedilol CR to determine whether the differing pharmacologic actions among beta-blockers result in varying effects on cardiovascular risk factors.

Adrenergic beta-Antagonists↗
PubMed2006

Recommendations for chamber quantification.

Quantification of cardiac chamber size, ventricular mass and function ranks among the most clinically important and most frequently requested tasks of echocardiography. Over the last decades, echocardiographic methods and techniques have improved and expanded dramatically, due to the introduction of higher frequency transducers, harmonic imaging, fully digital machines, left-sided contrast agents, and other technological advancements. Furthermore, echocardiography due to its portability and versatility is now used in emergency rooms, operating rooms, and intensive care units. Standardization of measurements in echocardiography has been inconsistent and less successful, compared to other imaging techniques and consequently, echocardiographic measurements are sometimes perceived as less reliable. Therefore, the American Society of Echocardiography, working together with the European Association of Echocardiography, a branch of the European Society of Cardiology, has critically reviewed the literature and updated the recommendations for quantifying cardiac chambers using echocardiography. This document reviews the technical aspects on how to perform quantitative chamber measurements of morphology and function, which is a component of every complete echocardiographic examination.

Cardiac Volume↗
PubMed2006

Predictors of remodeling in the CRT era: influence of mitral regurgitation, BNP, and gender.

BACKGROUND: We analyzed quantitative echocardiographic data from a large heart failure cohort receiving medical and cardiac resynchronization therapy (CRT) to determine baseline predictors of progressive left ventricular (LV) enlargement. METHODS AND RESULTS: Quantitative echocardiograms were obtained at baseline and after 6 months in 776 outpatients with chronic heart failure who participated in MIRACLE (Multicenter InSync Randomized Clinical Evaluation) and MIRACLE-ICD (Multicenter InSync ICD Randomized Clinical Evaluation). We used multivariable regression to determine clinical, therapeutic, and echocardiographic characteristics that predicted a subsequent change in left ventricular end-diastolic volume (LVEDV). Over 6 months, LVEDV increased in 308 (40%) and decreased in 468 (60%) patients. Baseline mitral regurgitation and levels of plasma brain natriuretic peptide (BNP) independently predicted LV enlargement, whereas CRT predicted a decrease in LVEDV (all P < .01). In all models tested, male gender was an independent risk factor for progressive LV enlargement (P < .0001). CONCLUSION: Men show more prominent LV dilation than women in chronic heart failure despite medical and device therapy. Rates of LV remodeling are influenced further by mitral regurgitation, plasma BNP, and CRT. Future studies should take these clinical factors into account when determining the influence of genetic factors and novel therapies on ventricular remodeling in chronic heart failure.

Aged↗
PubMed2006

Risk assessment in patients with depressed left ventricular function after myocardial infarction using the myocardial performance index--Survival and Ventricular Enlargement (SAVE) experience.

BACKGROUND: Myocardial performance index (MPI) is a noninvasive, quantitative Doppler measure of global cardiac function, integrating systolic and diastolic functions. The prognostic significance of MPI is less clear for cardiovascular (CV) events after myocardial infarction (MI) among individuals at high risk with depressed left ventricular (LV) systolic function. METHODS: We analyzed echocardiograms from 512 patients with depressed LV function after MI enrolled in the Survival and Ventricular Enlargement (SAVE) echocardiographic substudy. Baseline MPI measures were obtainable in 226 patients. The cohort was separated by median MPI (0.50). MPI was related to baseline clinical and echocardiographic characteristics, ventricular remodeling, and subsequent CV events, including recurrent MI, heart failure, CV death, and a composite of all CV end points. RESULTS: An MPI of 0.5 or more was associated with larger infarct size and reduced LV systolic function at baseline; other baseline characteristics between the groups were similar. A total of 64 (28.3%) patients experienced CV events. Baseline MPI did not influence ventricular remodeling and did not modify the relationship between ventricular dilatation and CV events. After covariate adjustment, an MPI of 0.50 or higher remained an independent predictor for adverse CV events (hazard ratio [HR], 2.00, 95% confidence interval 1.17-3.43). CONCLUSIONS: An MPI of 0.50 or greater is an independent predictor for CV events after MI in patients with known LV dysfunction.

Cohort Studies↗
PubMed2005

Echocardiographic predictors of morbidity and mortality in patients with advanced heart failure: the Beta-blocker Evaluation of Survival Trial (BEST).

OBJECTIVES: The aim of this study was to determine echocardiographic predictors of outcome in patients with advanced heart failure (HF) due to severe left ventricular (LV) systolic dysfunction in the Beta-blocker Evaluation of Survival Trial (BEST). BACKGROUND: Previous studies indicate that echocardiographic measurements of LV size and function, mitral deceleration time, and mitral regurgitation (MR) predict adverse outcomes in HF. However, complete quantitative echocardiograms evaluating all of these parameters have not been reported in a prospective randomized clinical trial in the era of modern HF therapy. METHODS: Complete echocardiograms were performed in 336 patients at 26 sites and analyzed by a core laboratory. A Cox proportional-hazards regression model was used to determine which echocardiographic variables predicted the primary end point of death or the secondary end point of death, HF hospitalization, or transplant. Significant variables were then entered into a multivariable model adjusted for clinical and demographic covariates. RESULTS: On multivariable analysis adjusted for clinical covariates, only LV end-diastolic volume index predicted death (events = 75), with a cut point of 120 ml/m(2). Three echocardiographic variables predicted the combined end point of death (events = 75), HF hospitalization (events = 97), and transplant (events = 9): LV end-diastolic volume index, mitral deceleration time, and the vena contracta width of MR. Optimal cut points for these variables were 120 ml/m(2), 150 ms, and 0.4 cm, respectively. CONCLUSIONS: Echocardiographic predictors of outcome in advanced HF include LV end-diastolic volume index, mitral deceleration time, and vena contracta width. These variables indicate that LV remodeling, increased LV stiffness, and MR are independent predictors of outcome in patients with advanced HF.

Echocardiography, Doppler↗
PubMed2005

Prognostic use of echocardiography 1 year after a myocardial infarction.

BACKGROUND: Left ventricular (LV) and right ventricular (RV) function are known predictors of morbidity and mortality after an acute myocardial infarction (MI). However, the prognostic use of a late evaluation of cardiac function after an MI remains unclear. METHODS: We analyzed echocardiograms obtained 1 year after MI in patients with LV dysfunction at baseline (ejection fraction [EF] < or = 40%) from 291 patients enrolled in the SAVE echocardiographic substudy who did not develop heart failure (HF) or a recurrent MI during this first year. Left ventricular EF and RV fractional area change were assessed. RESULTS: After a median follow-up of 22 months after the 1-year echocardiogram, a low LVEF (< 30%) at 1 year was associated with an increased risk of death and/or HF (hazards ratio [HR] 2.7, 95% CI 1.3-5.3). Presence of RV dysfunction was also associated with an increased risk of death (HR 8.9, 95% CI 3.5-22.1), development of HF (HR 7.1, 95% CI 3.4-15.0), and the composite end point of death or HF (HR 7.6, 95% CI 4.1-14.2). In multivariate analyses, both low LVEF and RV dysfunction remained independently predictive of the composite end point of death or HF. Patients with biventricular dysfunction were at the greatest risk of death and/or HF (HR 19.4, 95% CI 8.2-46.0) in follow-up. CONCLUSIONS: In a stable population of survivors of MI, impaired LV and RV function at 1 year after MI are independently and additively predictive of increased risk of HF or death.

Female↗
PubMed2004

Echocardiographic evaluation of cardiac resynchronization therapy: ready for routine clinical use? A critical appraisal.

Cardiac resynchronization therapy (CRT) has been proposed as an alternative treatment in patients with severe, drug-refractory heart failure. The clinical results are promising, and improvement in symptoms, exercise capacity, and systolic left ventricular (LV) function have been demonstrated after CRT, accompanied by a reduction in hospitalization and a superior survival as compared with optimized medical therapy alone. However, 20% to 30% of patients do not respond to CRT. Currently, patients are selected mainly on electrocardiogram criteria (wide QRS complex, left bundle branch block configuration). In view of the 20% to 30% of nonresponders, additional selection criteria are needed. Echocardiography (and, in particular, tissue Doppler imaging) may allow further identification of potential responders to CRT, based on assessment of inter- and intraventricular dyssynchrony. In addition, echocardiography may allow optimal LV lead positioning and follow-up after CRT. In the current review, the different echocardiographic approaches to predict response to CRT are discussed. In addition, the use of echocardiography to guide LV lead positioning and follow-up after CRT are addressed.

Clinical Trials as Topic↗
PubMed2004

Effect of antecedent systemic hypertension on subsequent left ventricular dilation after acute myocardial infarction (from the Survival and Ventricular Enlargement trial).

Whether antecedent systemic hypertension influences the risk of subsequent left ventricular (LV) dilation in patients after an acute myocardial infarction with LV systolic dysfunction is unclear. We assessed echocardiographic evidence of ventricular remodeling from baseline (mean +/- SD 11 +/- 3 days) to 2 years after an acute myocardial infarction in 122 hypertensive (defined as a history of treated hypertension, baseline systolic blood pressure > or =140 or baseline diastolic blood pressure > or =90 mm Hg) and 334 nonhypertensive patients in the Survival and Ventricular Enlargement echocardiographic substudy. Compared with nonhypertensives, baseline heart size, defined as the sum of the average short- and long-axis LV cavity areas, was similar (70.1 +/- 11.9 vs 68.8 +/- 11.2 cm(2), p = 0.33 at end-diastole; 50.1 +/- 11.3 vs 48.8 +/- 10.8 cm(2), p = 0.31 at end-systole), but short-axis LV myocardial area (24.7 +/- 4.3 vs 25.7 +/- 5.0 cm(2), p = 0.043) and wall thickness (1.15 +/- 0.16 vs 1.21 +/- 0.17 cm, p = 0.004) at end-diastole were greater among hypertensives. The myocardial infarct segment lengths were similar in the 2 groups (p = 0.22). Although LV cavity areas increased significantly in the 2 groups from baseline to 2 years (p < or =0.001), the increase was significantly greater in hypertensives than in nonhypertensives (+5.6 +/- 11.5 vs +2.2 +/- 10.7 cm(2), p = 0.005 at end-diastole; +6.23 +/- 12.75 vs +2.94 +/- 11.4 cm(2), p = 0.012 at end-systole). There was no concomitant difference in the change in LV myocardial area or LV wall thickness between the 2 groups (p >0.30). After adjusting for known confounders, antecedent hypertension was associated with a doubling of the risk of LV dilation (50.8% vs 37.7%, odds ratio 2.09, 95% confidence interval 1.27 to 3.45, p = 0.004). This association was not modified by diabetes mellitus, myocardial infarct segment length, or captopril use (all p values for interaction >0.10). We conclude that antecedent hypertension is associated with subsequent LV dilation in patients after acute myocardial infarction with LV systolic dysfunction.

Antihypertensive Agents↗
PubMed2004

Effect of left ventricular remodeling after cardiac resynchronization therapy on frequency of ventricular arrhythmias.

We evaluated whether cardiac resynchronization therapy affects the prevalence of ventricular tachycardia in relation to reverse remodeling in patients with end-stage heart failure. Clinical, echocardiographic, and implantable cardioverter-defibrillator (ICD) data of 17 patients with ICDs were obtained before and after they had received an upgrade to an ICD-cardiac resynchronization therapy device.

Adult↗
PubMed2003

Myocardial contractile reserve by dobutamine stress echocardiography predicts improvement in ejection fraction with beta-blockade in patients with heart failure: the Beta-Blocker Evaluation of Survival Trial (BEST).

BACKGROUND: beta-Blockers improve survival and reduce hospitalization in chronic heart failure (CHF) by biologically improving left ventricular ejection fraction (LVEF). However, a good predictor of improvement with this therapy has not been identified. This substudy of BEST examined whether myocardial contractile reserve, as determined by dobutamine stress echocardiography, predicts improvement in LVEF. METHODS AND RESULTS: Seventy-nine patients with class III/IV CHF underwent dobutamine stress echocardiography before treatment with bucindolol (n=41) or placebo (n=38). Regional wall motion score index (WMSI) was calculated as the sum of the scores in each segment divided by the total number of segments visualized. WMSI was compared with change in LVEF after 3 months of therapy as determined by gated radionuclide scan. Change in WMSI correlated inversely with change in LVEF after 3 months of bucindolol (r=-0.72, P<0.0001) and was the most significant multivariate predictor of change in LVEF (P=0.0002). Patients with contractile reserve had demographics similar to those of patients without contractile reserve, including RVEF, LVEF, systolic blood pressure, and CHF duration. However, patients without contractile reserve had higher baseline plasma norepinephrine levels (687+/-333 versus 420+/-246 pg/mL, P<0.05) and greater decrease in plasma norepinephrine in response to bucindolol (-249+/-171 versus -35+/-277 pg/mL, P<0.05). CONCLUSIONS: This study suggests a direct relationship between contractile reserve and improvement in LVEF with beta-blocker therapy in patients with advanced CHF. Patients without contractile reserve have higher resting adrenergic drive, as reflected by plasma norepinephrine, and may experience greater sympatholytic effects from bucindolol.

Adrenergic beta-Antagonists↗
PubMed2003

Left ventricular remodeling and ventricular arrhythmias after myocardial infarction.

BACKGROUND: The relation between left ventricular (LV) remodeling and ventricular arrhythmias after myocardial infarction is poorly documented. We investigated the relations between LV size, hypertrophy, and function and ventricular arrhythmias in 263 patients from the Survival and Ventricular Enlargement (SAVE) study, using quantitative 2D echocardiography and ambulatory ECG monitoring after myocardial infarction. METHODS AND RESULTS: Transthoracic 2D echocardiograms and arrhythmia monitoring were performed at baseline (mean, 11 days) and 1 and 2 years after infarction. LV size, short-axis muscle (mass) area (LVMA), and function were quantified from 2D echocardiograms. The prevalence of ventricular tachycardia (VT) and frequent ventricular ectopy (premature ventricular contractions [PVCs] >10/h) was assessed from ambulatory ECG. VT and PVCs >10/h occurred in 20% and 29% of patients at baseline, in 22% and 35% at 1 year and 23% and 39% at 2 years, respectively. VT and PVCs >10/h at baseline and 1 and 2 years were significantly related to LV size, LVMA, and function. Furthermore, changes in LV size and function from baseline to 2 years predicted both VT and PVCs >10/h. The study was underpowered to detect treatment effect of ACE inhibitors and beta-adrenergic receptor blockers but did not alter the relations between ventricular arrhythmias, LV size, and function. CONCLUSIONS: Quantitative echocardiographic assessment of LV size, LVMA, and function and changes in these measurements over time predict ventricular arrhythmias after infarction. Altered LV architecture and function during postinfarction LV remodeling provide an important substrate for triggering high-grade ventricular arrhythmias.

Adrenergic beta-Antagonists↗
PubMed2003

Hypertrophic cardiomyopathy. Pathophysiology, diagnosis, and treatment.

Hypertrophic cardiomyopathy is one of the most common inherited cardiovascular diseases and is characterized by a heterogeneous appearance and natural history. Although previously thought to be a disease of the young, HCM is frequently diagnosed in patients over age 50. A careful history and physical examination and readily available non-invasive testing will diagnose most cases, but genetic testing can identify those not expressing the typical phenotype. Treatment of symptomatic patients is targeted toward improving LV diastolic function; for patients with the obstructive form HCM, treatment involves relieving outflow tract obstruction. Identification of those at risk for sudden death may require consideration of prophylactic defibrillator placement.

Aged↗
PubMed2002

Echocardiographic assessment of pulmonary hypertension in patients with advanced lung disease.

Doppler echocardiography is commonly used to estimate systolic pulmonary artery pressure and to diagnose pulmonary hypertension, but data relating to its utility in patients with advanced lung disease are limited. In a cohort study of 374 lung transplant candidates, the performance characteristics of echocardiography compared with right heart catheterization in the determination of systolic pulmonary artery pressure and diagnosis of pulmonary hypertension were investigated. The prevalence of pulmonary hypertension was 25% in the study population. Estimation of systolic pulmonary artery pressure by echocardiography was possible in 166 patients (44%). The correlation between systolic pulmonary artery pressure estimated by echocardiography and measured by cardiac catheterization was good (r = 0.69, p < 0.0001). However, 52% of pressure estimations were found to be inaccurate (more than 10 mm Hg difference compared with measured pressure), and 48% of patients were misclassified as having pulmonary hypertension by echocardiography. Sensitivity, specificity, and positive and negative predictive values of systolic pulmonary artery pressure estimation for diagnosis of pulmonary hypertension were 85%, 55%, 52%, and 87%, respectively. In conclusion, despite a statistically significant correlation with directly measured values, estimation of systolic pulmonary artery pressure by echocardiography is frequently inaccurate in patients with advanced lung disease and leads to considerable overdiagnosis of pulmonary hypertension.

Adult↗
PubMed2002

Ventricular remodeling does not accompany the development of heart failure in diabetic patients after myocardial infarction.

BACKGROUND: Diabetic patients are at increased risk for heart failure (HF) and other adverse events after myocardial infarction (MI). Left ventricular (LV) enlargement after MI is also associated with the same increased risk. We used data from the Survival and Ventricular Enlargement (SAVE) echocardiographic substudy to test the hypothesis that diabetes was associated with increased LV enlargement after MI. METHODS AND RESULTS: Four hundred twelve nondiabetic and 100 diabetic patients underwent echocardiographic assessment at baseline and 3 months, 1 year, and 2 years after MI. HF developed in 30% of diabetic and 17% of nondiabetic patients during follow-up (P<0.001). Baseline LV diastolic size, ejection fraction, and infarct segment length were similar between diabetic and nondiabetic patients. Diabetic patients demonstrated less LV enlargement between baseline and 2 years than nondiabetic patients (0.9+/-11.1 cm2 versus 3.8+/-10.9 cm2, P=0.047). In patients who developed HF, LV diastolic dilatation (10.0+/-12.4 cm2 versus 3.7+/-13.1 cm2, P=0.06) and systolic dilatation (4.6+/-11.8 versus 0.91+/-12.1, P=0.017) were greater in nondiabetic than in diabetic patients. LV dilatation between baseline and 2 years was a predictor of HF in nondiabetic patients, but not in diabetic patients, even after excluding patients with recurrent MI and adjusting for history of hypertension, prior MI, age, treatment group, and smoking. Diabetes modified the relationship between ventricular enlargement and the risk of HF (P=0.011). CONCLUSIONS: The increased incidence of HF after MI in diabetic patients is not explained by a greater propensity for LV remodeling.

Diabetes Complications↗
PubMed2002

Right ventricular dysfunction and risk of heart failure and mortality after myocardial infarction.

OBJECTIVES: The aim of this study was to determine the prognostic value of right ventricular (RV) function in patients after a myocardial infarction (MI). BACKGROUND: Right ventricular function has been shown to predict exercise capacity, autonomic imbalance and survival in patients with advanced heart failure (HF). METHODS: Two-dimensional echocardiograms were obtained in 416 patients with left ventricular (LV) dysfunction (ejection fraction [LVEF] < or = 40%) from the Survival And Ventricular Enlargement (SAVE) echocardiographic substudy (mean 11.1 +/- 3.2 days post infarction). Right ventricular function from the apical four-chamber view, assessed as the percent change in the cavity area from end diastole to end systole (fractional area change [FAC]), was related to clinical outcome. RESULTS: Right ventricular function correlated only weakly with the LVEF (r = 0.12, p = 0.013). On univariate analyses, the RV FAC was a predictor of mortality, cardiovascular mortality and HF (p < 0.0001 for all) but not recurrent MI. After adjusting for age, gender, diabetes mellitus, hypertension, previous MI, LVEF, infarct size, cigarette smoking and treatment assignment, RV function remained an independent predictor of total mortality, cardiovascular mortality and HF. Each 5% decrease in the RV FAC was associated with a 16% increased odds of cardiovascular mortality (95% confidence interval 4.3% to 29.2%; p = 0.006). CONCLUSIONS: Right ventricular function is an independent predictor of death and the development of HF in patients with LV dysfunction after MI.

Aged↗