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1.
Minerva Cardioangiol ; 52(4): 263-72, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15284677

ABSTRACT

The diagnosis and treatment of aortic valve disease can be challenging for the clinician. Aortic regurgitation (AR) may be evaluated with Doppler echocardiography or catheterization. Medical therapy consists of vasodilators. Surgery may be appropriate for patients with symptoms, left ventricular dilatation or diminished left ventricle systolic function. Aortic stenosis (AS) can be evaluated with the same modalities as AR. There is evidence that statin therapy may slow the progression of AS. Contrary to conventional wisdom, vasodilators are safe and effective in certain patients. Surgical valve replacement is performed for symptoms and in certain asymptomatic patients.


Subject(s)
Aortic Valve Insufficiency/therapy , Aortic Valve Stenosis/therapy , Aortic Valve Insufficiency/diagnosis , Aortic Valve Insufficiency/drug therapy , Aortic Valve Insufficiency/surgery , Aortic Valve Stenosis/diagnosis , Aortic Valve Stenosis/drug therapy , Aortic Valve Stenosis/surgery , Heart Valve Prosthesis Implantation/methods , Humans , Treatment Outcome , Vasodilator Agents/therapeutic use
2.
J Heart Valve Dis ; 10(5): 681-5, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11603609

ABSTRACT

Radiation-associated valvular dysfunction is characterized by variable aortic and mitral valve thickening. A review of three patients assessed echocardiographically revealed that radiation-associated valvular dysfunction after radiation treatment for Hodgkin's disease may be characterized by a unique and consistent pattern of thickening of the aortic and mitral valves involving the aortic-mitral curtain.


Subject(s)
Aortic Valve/radiation effects , Heart Valve Diseases/etiology , Hodgkin Disease/complications , Hodgkin Disease/radiotherapy , Mitral Valve/radiation effects , Radiation Pneumonitis/complications , Female , Heart Valve Diseases/mortality , Hodgkin Disease/mortality , Humans , Male , Middle Aged , Radiation Pneumonitis/mortality , Treatment Failure
3.
Circulation ; 104(7): 779-82, 2001 Aug 14.
Article in English | MEDLINE | ID: mdl-11502702

ABSTRACT

BACKGROUND: The diagnosis of diastolic heart failure is generally made in patients who have the signs and symptoms of heart failure and a normal left ventricular (LV) ejection fraction. Whether the diagnosis also requires an objective measurement of parameters that reflect the diastolic properties of the ventricle has not been established. METHODS AND RESULTS: We hypothesized that the vast majority of patients with heart failure and a normal ejection fraction exhibit abnormal LV diastolic function. We tested this hypothesis by prospectively identifying 63 patients with a history of heart failure and an echocardiogram suggesting LV hypertrophy and a normal ejection fraction; we then assessed LV diastolic function during cardiac catheterization. All 63 patients had standard hemodynamic measurements; 47 underwent detailed micromanometer and echocardiographic-Doppler studies. The LV end-diastolic pressure was >16 mm Hg in 58 of the 63 patients; thus, 92% had elevated end-diastolic pressure (average, 24+/-8 mm Hg). The time constant of LV relaxation (average, 51+/-15 ms) was abnormal in 79% of the patients. The E/A ratio was abnormal in 48% of the patients. The E-wave deceleration time (average, 349+/-140 ms) was abnormal in 64% of the patients. One or more of the indexes of diastolic function were abnormal in every patient. CONCLUSIONS: Objective measurement of LV diastolic function serves to confirm rather than establish the diagnosis of diastolic heart failure. The diagnosis of diastolic heart failure can be made without the measurement of parameters that reflect LV diastolic function.


Subject(s)
Diastole , Heart Failure/diagnosis , Stroke Volume , Ventricular Dysfunction, Left/diagnosis , Cardiac Catheterization , Diagnosis, Differential , Echocardiography, Doppler , Female , Heart Failure/classification , Heart Failure/physiopathology , Hemodynamics , Humans , Hypertrophy, Left Ventricular/diagnosis , Hypertrophy, Left Ventricular/physiopathology , Male , Manometry , Middle Aged , Predictive Value of Tests , Prospective Studies , Ventricular Dysfunction, Left/physiopathology
4.
J Am Coll Cardiol ; 37(4): 1042-8, 2001 Mar 15.
Article in English | MEDLINE | ID: mdl-11263606

ABSTRACT

OBJECTIVES: We sought to assess the ability of echocardiographic indices of systolic and diastolic function to predict incident congestive heart failure (CHF). BACKGROUND: Noninvasive indices of subclinical systolic and/or diastolic dysfunction that can be used to identify patients in a transition phase between normal cardiac function and clinical CHF would be valuable. Though midwall shortening and Doppler mitral inflow patterns are seemingly well suited to predict subsequent CHF, the predictive value of these indices has not been investigated. METHODS: We studied 2,671 participants in the Cardiovascular Health Study who were free of coronary heart disease, CHF or atrial fibrillation. Clinical and quantitative echocardiographic data were obtained in all participants. RESULTS: At a mean follow-up of 5.2 years (range 0 to 6 years), 170 participants (6.4% of the cohort) developed CHF. Although 96% of these participants had normal or borderline ejection fraction (EF) at baseline, only 57% had normal or borderline EF at the time of hospitalization. In multivariate modeling, fractional shortening at the endocardium (relative risk [RR] 1.85 per 10-unit decrease, confidence interval [CI] 1.27 to 2.39), fractional shortening at the midwall (RR 1.29 per five-unit decrease, 95% CI 1.11-1.51) and peak Doppler peak E (RR 1.15 for each 0.1 M/s increment; CI 1.02 to 1.21) independently predicted incident CHF. Both high and low Doppler E/A ratios were predictive of incident CHF. CONCLUSIONS: Roughly half the occurrences of CHF in this population are associated with normal or borderline EF. Echocardiographic findings suggestive of subclinical contractile dysfunction and diastolic filling abnormalities are both predictive of subsequent CHF. The standard (FSendo) and refined (FSmw) parameters of systolic function performed similarly in this regard, though subjects with left ventricular hypertrophy and depressed FSmw are at particularly high risk for subsequent CHF.


Subject(s)
Echocardiography , Heart Failure/diagnostic imaging , Age Factors , Aged , Aged, 80 and over , Diastole , Female , Follow-Up Studies , Heart Failure/physiopathology , Humans , Male , Multivariate Analysis , Myocardial Contraction , Predictive Value of Tests , Prognosis , Proportional Hazards Models , Risk Factors , Systole
5.
J Am Coll Cardiol ; 37(4): 1080-4, 2001 Mar 15.
Article in English | MEDLINE | ID: mdl-11263612

ABSTRACT

OBJECTIVES: We sought to determine whether the cardiocyte microtubule network densification characteristic of animal models of severe pressure overload cardiac hypertrophy occurs in human patients. BACKGROUND: In animal models of clinical entities causative of severe right and left ventricular (LV) pressure overload hypertrophy, increased density of the cellular microtubule network, through viscous loading of active myofilaments, causes contractile dysfunction that is normalized by microtubule depolymerization. These linked contractile and cytoskeletal abnormalities, based on augmented tubulin synthesis and microtubule stability, progress during the transition to heart failure. METHODS: Thirteen patients with symptomatic aortic stenosis (AS) (aortic valve area = 0.6 +/- 0.1 cm2) and two control patients without AS were studied. No patient had aortic insufficiency, significant coronary artery disease or abnormal segmental LV wall motion. Left ventricular function was assessed by echocardiography and cardiac catheterization before aortic valve replacement. Left ventricular biopsies obtained at surgery before cardioplegia were separated into free and polymerized tubulin fractions before analysis. Midwall LV fractional shortening versus mean LV wall stress in the AS patients was compared with that in 84 normal patients. RESULTS: Four AS patients had normal LV function and microtubule protein concentration; six had decreased LV function and increased microtubule protein concentration, and three had borderline LV function and microtubule protein concentration, such that there was an inverse relationship of midwall LV fractional shortening to microtubule protein. CONCLUSIONS: In patients, as in animal models of severe LV pressure overload hypertrophy, myocardial dysfunction is associated with increased microtubules, suggesting that this may be one mechanism contributing to the development of congestive heart failure in patients with AS.


Subject(s)
Aortic Valve Stenosis/complications , Hypertrophy, Left Ventricular/metabolism , Myocardium/chemistry , Tubulin/analysis , Aged , Female , Humans , Hypertrophy, Left Ventricular/etiology , Hypertrophy, Left Ventricular/physiopathology , Immunohistochemistry , Male , Middle Aged , Ventricular Function, Left
6.
Am J Cardiol ; 87(6): 732-6, 2001 Mar 15.
Article in English | MEDLINE | ID: mdl-11249892

ABSTRACT

This study assesses and evaluates left ventricular (LV) contractile function after treatment of hypertension, with an emphasis on LV midwall mechanics. Although prior studies have assessed cardiac function after hypertension treatment, none has performed an analysis of LV midwall mechanics. The Veterans Affairs Study of monotherapy in hypertension was a study large enough to permit analysis of midwall mechanics across a wide spectrum of mass changes accompanying hypertension treatment. LV chamber function was assessed by computing fractional shortening at the endocardial surface; LV midwall shortening was used to define myocardial function. Both shortening indexes were related to end-systolic circumferential stress in the entire population by partitioning values of mass and relative wall thickness changes. Two hundred sixty-eight patients were studied at baseline and again after a 1- or 2-year period. In the entire group, there was no significant change in circumferential shortening either at the endocardium (38 +/- 8% at baseline vs 37 +/- 7% at follow up, p = 0.29) or in shortening at the midwall (20 +/- 3% vs 20 +/- 3%, p = 0.53). However, 83 patients had a reduction in relative wall thickness and an increase in midwall shortening. The change in midwall shortening was significantly related to changes in relative wall thickness (r = -0.53, p = 0.0001). Thus, reductions in LV mass associated with antihypertensive therapy are generally not accompanied by a decrement in LV chamber or myocardial function. Improvement in midwall shortening is more closely related to normalization of LV geometry than to reduction in LV mass.


Subject(s)
Hypertension/drug therapy , Myocardial Contraction/drug effects , Ventricular Function, Left/drug effects , Analysis of Variance , Blood Pressure/drug effects , Echocardiography , Heart Ventricles/diagnostic imaging , Humans , Hypertension/diagnostic imaging , Hypertension/physiopathology , Randomized Controlled Trials as Topic
7.
Circulation ; 103(5): 678-83, 2001 Feb 06.
Article in English | MEDLINE | ID: mdl-11156879

ABSTRACT

BACKGROUND: It is still unclear whether substantial regression of hypertensive left ventricular hypertrophy (LVH) and normalization of chamber geometry are associated with improved left ventricular (LV) myocardial function. METHODS AND RESULTS: Midwall mechanics were evaluated in 152 patients undergoing 1 year of effective antihypertensive treatment. Two-dimensionally directed M-mode echocardiography was performed as follows: (1) after a 4-week placebo "run-in" period, (2) after 1 year of treatment with 20 mg/d lisinopril (alone or associated with 12.5 to 25 mg/d hydrochlorothiazide), and (3) after a final 1-month placebo period to allow blood pressure (24-hour average ambulatory monitoring) to return to pretreatment levels. Treatment-induced reductions in blood pressure (from 149+/-16/95+/-11 to 131+/-12/83+/-10 mm Hg, P:<0.05) and circumferential end-systolic wall stress (from 84+/-22 to 72+/-19 g/cm(2), P:<0.05) were associated with a marked reduction in LV mass index (from 159+/-30 to 133+/-26 g/m(2), P:<0.05). LVH regression was accompanied by an increase in midwall fractional shortening (from 19.7+/-2.7% to 20.9+/-2.7%, P:<0.05) and by a decrease in relative wall thickness (from 48.2+/-7.7% to 44.1+/-6.7%, P:<0.05). The improvement in midwall function associated with afterload reduction and substantial LVH regression persisted after antihypertensive therapy withdrawal and restoration of the hypertensive state. Despite a significant increase in end-systolic wall stress, further LV chamber remodeling did not occur. The preservation of relative wall thickness was associated with a persistent improvement in midwall systolic function. CONCLUSIONS: Regression of concentric LVH is associated with an improvement of midwall systolic function, which is more dependent on the normalization of LV geometry than on the reduction in LV systolic stress.


Subject(s)
Hypertension/complications , Hypertrophy, Left Ventricular/physiopathology , Ventricular Remodeling , Adult , Aged , Antihypertensive Agents/adverse effects , Blood Pressure , Female , Heart Function Tests , Humans , Hypertension/physiopathology , Hypertrophy, Left Ventricular/etiology , Male , Middle Aged , Myocardial Contraction
8.
Am J Cardiol ; 87(1): 54-60, 2001 Jan 01.
Article in English | MEDLINE | ID: mdl-11137834

ABSTRACT

Left ventricular (LV) ejection fraction is normal in most patients with uncomplicated hypertension, but the prevalence and correlates of decreased LV systolic chamber and myocardial function, as assessed by midwall mechanics, in hypertensive patients identified as being at high risk by the presence of LV hypertrophy on the electrocardiogram has not been established. Therefore echocardiograms were obtained in 913 patients with stage I to III hypertension and LV hypertrophy determined by electrocardiographic (Cornell voltage duration or Sokolow-Lyon voltage) criteria after 14 days' placebo treatment. The 913 patients' mean age was 66 years, and 42% were women. Fourteen percent had subnormal LV endocardial shortening, 24% had subnormal midwall shortening, and 13% had reduced stress-corrected midwall shortening. Nineteen percent had normal LV geometry, 11% had concentric remodeling, 47% had eccentric hypertrophy, and 23% had concentric hypertrophy. LV systolic performance evaluated by LV endocardial shortening and midwall shortening was impaired in 10% of patients with normal geometry, 20% with concentric remodeling, 27% with eccentric hypertrophy, and 42% with concentric hypertrophy. Relative wall thickness, an important independent correlate of LV chamber function, was related directly to endocardial shortening and negatively to midwall shortening and stress-corrected midwall shortening. LV mass was the strongest independent correlate of impaired endocardial shortening, midwall shortening, or both. In hypertensive patients with electrocardiographic LV hypertrophy, indexes of systolic performance are subnormal in 10% to 42% with different LV geometric patterns. Depressed endocardial shortening is most common in patients with eccentric LV hypertrophy, whereas impaired midwall shortening is most prevalent in patients with concentric remodeling or hypertrophy. Thus, in hypertensive patients with electrocardiographic LV hypertrophy, impaired LV performance occurs most often, and is associated with greater LV mass and relative wall thickness and may contribute to the high rate of cardiovascular events.


Subject(s)
Electrocardiography , Hypertension/physiopathology , Hypertrophy, Left Ventricular/physiopathology , Ventricular Dysfunction, Left/physiopathology , Aged , Analysis of Variance , Echocardiography , Female , Humans , Hypertrophy, Left Ventricular/diagnostic imaging , Male , Middle Aged , Regression Analysis , Ventricular Dysfunction, Left/diagnostic imaging
9.
Am J Cardiol ; 86(6): 669-74, 2000 Sep 15.
Article in English | MEDLINE | ID: mdl-10980221

ABSTRACT

Suboptimal left ventricular (LV) cavity visualization and endocardial border delineation often compromise the clinical utility of echocardiography. This study examines the safety and efficacy of perflutren, a novel ultrasound contrast agent, for LV cavity opacification and endocardial border delineation in patients with suboptimal baseline echocardiograms. In a multicenter, randomized, placebo-controlled, double-blind trial, 211 patients with suspected cardiac disease and suboptimal baseline echocardiograms were enrolled at 17 sites. Two intravenous injections of either placebo (saline) or perflutren (5 or 10 microl/kg) were given approximately 30 minutes apart. Images of the apical 4- and 2-chamber views were acquired and scored. Perflutren opacified the LV cavity after both dosages (5 and 10 microl/kg dosages). Clinically useful contrast was observed in 89% of patients who received perflutren and in 0% of patients who received placebo (p < 0.01). Quantitative assessment of LV opacification with videodensitometry showed similar results. The mean duration of clinically useful contrast was 90 seconds. Improvement in endocardial border delineation was demonstrated in 91% of patients who received perflutren and in 12% of those who received placebo (p < 0.001). Following perflutren, an average of 4 more segments per patient were evaluable compared with baseline. Salvage of nondiagnostic baseline examinations by perflutren was demonstrated in 48% of eligible subjects. The safety profile of perflutren was similar to placebo. These data indicate that administration of perflutren to patients with suboptimal baseline images is well tolerated and provides substantial LV cavity opacification and improvement in endocardial border delineation.


Subject(s)
Contrast Media , Echocardiography/methods , Fluorocarbons , Heart Ventricles/diagnostic imaging , Ventricular Dysfunction, Left/diagnostic imaging , Densitometry , Diagnosis, Differential , Double-Blind Method , Female , Humans , Injections, Intravenous , Male , Middle Aged , Prospective Studies , Reproducibility of Results , Safety , Video Recording
10.
J Am Coll Cardiol ; 35(6): 1628-37, 2000 May.
Article in English | MEDLINE | ID: mdl-10807470

ABSTRACT

OBJECTIVES: We sought to characterize the predictors of incident congestive heart failure (CHF), as determined by central adjudication, in a community-based elderly population. BACKGROUND: The elderly constitute a growing proportion of patients admitted to the hospital with CHF, and CHF is a leading source of morbidity and mortality in this group. Elderly patients differ from younger individuals diagnosed with CHF in terms of biologic characteristics. METHODS: We analyzed data from the Cardiovascular Health Study, a prospective population-based study of 5,888 elderly people >65 years old (average 73 +/- 5, range 65 to 100) at four locations. Multiple laboratory measures of cardiovascular structure and function, blood chemistries and functional assessments were obtained. RESULTS: During an average follow-up of 5.5 years (median 6.3), 597 participants developed incident CHF (rate 19.3/1,000 person-years). The incidence of CHF increased progressively across age groups and was greater in men than in women. On multivariate analysis, other independent predictors included prevalent coronary heart disease, stroke or transient ischemic attack at baseline, diabetes, systolic blood pressure (BP), forced expiratory volume 1 s, creatinine >1.4 mg/dl, C-reactive protein, ankle-arm index <0.9, atrial fibrillation, electrocardiographic (ECG) left ventricular (LV) mass, ECG ST-T segment abnormality, internal carotid artery wall thickness and decreased LV systolic function. Population-attributable risk, determined from predictors of risk and prevalence, was relatively high for prevalent coronary heart disease (13.1%), systolic BP > or =140 mm Hg (12.8%) and a high level of C-reactive protein (9.7%), but was low for subnormal LV function (4.1%) and atrial fibrillation (2.2%). CONCLUSIONS: The incidence of CHF is high in the elderly and is related mainly to age, gender, clinical and subclinical coronary heart disease, systolic BP and inflammation. Despite the high relative risk of subnormal systolic LV function and atrial fibrillation, the actual population risk of these for CHF is small because of their relatively low prevalence in community-dwelling elderly people.


Subject(s)
Geriatric Assessment , Heart Failure/diagnosis , Aged , Aged, 80 and over , Coronary Disease/diagnosis , Coronary Disease/mortality , Female , Heart Failure/mortality , Humans , Ischemic Attack, Transient/diagnosis , Ischemic Attack, Transient/mortality , Male , Prospective Studies , Risk Factors , Survival Rate
11.
J Heart Valve Dis ; 9(2): 273-5, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10772047

ABSTRACT

A 68-year-old woman was admitted to hospital for possible mitral valve surgery for severe mitral regurgitation (MR). Six months before admission, a DDD pacemaker was implanted for symptomatic bradycardia. She developed atrial fibrillation and the pacer was changed to a VVI mode. At cardiac catheterization, the pulmonary artery and wedge pressures were elevated; coronary angiography showed non-obstructive coronary artery disease. 2-D echocardiography confirmed preserved left ventricular function, severe MR and moderate tricuspid regurgitation. The change in pacing had a dramatic effect on MR severity; ventricular pacing was associated with a MR jet that occupied a larger area of the left atrium than with the unpaced rhythm, the continuous-wave mitral regurgitant Doppler profile was 'dagger'-shaped, and the signal intensity stronger compared with the unpaced rhythm. These findings are consistent with severe MR. The pacer was reprogrammed to reduce the pacing rate from 70 to 45 beats/min, allowing an unpaced rhythm for the most part. The patient improved and was discharged two days later. Six months later she was asymptomatic; repeat echocardiography confirmed mild to moderate MR.


Subject(s)
Echocardiography, Doppler, Color , Mitral Valve Insufficiency/diagnostic imaging , Pacemaker, Artificial , Aged , Disease Progression , Female , Follow-Up Studies , Heart Rate/physiology , Hemodynamics/physiology , Humans , Mitral Valve/diagnostic imaging , Mitral Valve/physiopathology , Mitral Valve Insufficiency/physiopathology
13.
Am J Cardiol ; 83(8): 1277-80, A9, 1999 Apr 15.
Article in English | MEDLINE | ID: mdl-10215300

ABSTRACT

This study demonstrated that, compared with normal controls, coronary artery dimensions are not increased appropriately for the increase in left ventricular mass in patients with nonischemic cardiomyopathy. The extent of coronary artery dimension to left ventricular mass mismatch did not correlate with the severity of heart failure.


Subject(s)
Cardiomyopathy, Dilated/diagnostic imaging , Coronary Vessels/diagnostic imaging , Heart Ventricles/diagnostic imaging , Cardiac Catheterization , Cardiomyopathy, Dilated/physiopathology , Coronary Angiography , Echocardiography , Female , Follow-Up Studies , Heart Ventricles/physiopathology , Humans , Male , Middle Aged , Myocardial Contraction , Observer Variation , Stroke Volume
14.
Am J Cardiol ; 83(5): 792-4, A10, 1999 Mar 01.
Article in English | MEDLINE | ID: mdl-10080443

ABSTRACT

To assess the incremental value of velocity of shortening velocity parameters compared with simpler, more widely used, extent of shortening parameters in compensated left ventricular hypertrophy, we studied 52 patients with left ventricular hypertrophy and 63 age-matched controls. Velocity parameters did not provide incremental information beyond that obtained by extent of shortening parameters.


Subject(s)
Endocardium/physiopathology , Heart/physiopathology , Hypertension/physiopathology , Hypertrophy, Left Ventricular/physiopathology , Myocardial Contraction/physiology , Aged , Blood Pressure/physiology , Case-Control Studies , Echocardiography , Echocardiography, Doppler , Endocardium/diagnostic imaging , Evaluation Studies as Topic , Heart Ventricles/physiopathology , Humans , Hypertension/diagnostic imaging , Hypertrophy, Left Ventricular/diagnostic imaging , Middle Aged , Systole , Ventricular Pressure/physiology
15.
J Hypertens ; 16(12 Pt 1): 1813-22, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9869016

ABSTRACT

BACKGROUND: Increased sympathetic activity contributes to the progression of heart failure. Adenosine counteracts sympathetic activity by inhibition of presynaptic norepinephrine release and attenuation of the metabolic and contractile responses to beta-adrenergic stimulation. In this study, we tested the hypothesis that the adenosinergic effects (uptake blockade) of dipyridamole may retard the progression of pressure overload hypertrophy in the rat. METHODS AND RESULTS: To verify that the administration of dipyridamole increases myocardial adenosine levels in the rat, epicardial adenosine concentrations were measured from 12 isolated, perfused rat hearts exposed to 10(-7) and 10(-6) mol/l dipyridamole. Adenosine concentrations were increased with both doses of dipyridamole. Also, 9 weeks of dipyridamole treatment resulted in decreased sensitivity to the adenosine A1-receptor agonist, 2-chloro-N6-cyclopentyl adenosine, suggesting that dipyridamole increases adenosine levels in the intact rat. In the second part of the study, rats were divided into either abdominal aortic-banded or sham-operated groups and were treated with either dipyridamole or saline. After 9 weeks of treatment, two-dimensional Doppler echocardiographic studies were performed and the adrenergic responsiveness to 10(-8) mol/l isoproterenol was assessed in vitro. The saline-treated banded group demonstrated concentric left ventricular hypertrophy, abnormal diastolic filling, increased wet lung weights and attenuation of adrenergic responsiveness. In contrast, the dipyridamole-treated banded rats exhibited more concentric geometry (higher relative wall thickness with similar left ventricular mass), normal left ventricular filling characteristics and preserved adrenergic responsiveness. Systolic left ventricular chamber and myocardial function, as assessed by stress-endocardial and midwall shortening relationships, were not significantly altered by banding or dipyridamole treatment. CONCLUSIONS: Dipyridamole treatment prevented the development of abnormal left ventricular chamber filling, preserved adrenergic responsiveness and appeared to attenuate detrimental chamber remodeling in rats with pressure overload hypertrophy.


Subject(s)
Adenosine/antagonists & inhibitors , Dipyridamole/pharmacology , Hypertrophy, Left Ventricular/metabolism , Receptors, Adrenergic, beta/metabolism , Ventricular Function, Left/drug effects , Adenosine/blood , Animals , Blood Pressure/drug effects , Body Weight , Dipyridamole/therapeutic use , Heart/drug effects , Hypertrophy, Left Ventricular/drug therapy , Lung , Male , Myocardium/chemistry , Myocardium/metabolism , Myocardium/pathology , Organ Size , Perfusion , Rats , Rats, Sprague-Dawley , Receptors, Adrenergic, beta/physiology , Receptors, Purinergic P1/physiology , Sensitivity and Specificity , Survival , Systole/drug effects , Systole/physiology , Ventricular Function, Left/physiology
16.
J Am Coll Cardiol ; 32(1): 230-6, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9669275

ABSTRACT

OBJECTIVES: This study was performed to compare the safety and efficacy of intravenous 2% dodecafluoropentane (DDFP) emulsion (EchoGen) with that of active control (sonicated human albumin [Albunex]) for left ventricular (LV) cavity opacification in adult patients with a suboptimal echocardiogram. BACKGROUND: The development of new fluorocarbon-based echocardiographic contrast agents such as DDFP has allowed opacification of the left ventricle after peripheral venous injection. We hypothesized that DDFP was clinically superior to the Food and Drug Administration-approved active control. METHODS: This was a Phase III, multicenter, single-blind, active controlled trial. Sequential intravenous injections of active control and DDFP were given 30 min apart to 254 patients with a suboptimal echocardiogram, defined as one in which the endocardial borders were not visible in at least two segments in either the apical two- or four-chamber views. Studies were interpreted in blinded manner by two readers and the investigators. RESULTS: Full or intermediate LV cavity opacification was more frequently observed after DDFP than after active control (78% vs. 31% for reader A; 69% vs. 34% for reader B; 83% vs. 55% for the investigators, p < 0.0001). LV cavity opacification scores were higher with DDFP (2.0 to 2.5 vs. 1.1 to 1.5, p < 0.0001). Endocardial border delineation was improved by DDFP in 88% of patients versus 45% with active control (p < 0.001). Similar improvement was seen for duration of contrast effect, salvage of suboptimal echocardiograms, diagnostic confidence and potential to affect patient management. There was no difference between agents in the number of patients with adverse events attributed to the test agent (9% for DDFP vs. 6% for active control, p = 0.92). CONCLUSIONS: This Phase III multicenter trial demonstrates that DDFP is superior to sonicated human albumin for LV cavity opacification, endocardial border definition, duration of effect, salvage of suboptimal echocardiograms, diagnostic confidence and potential to influence patient management. The two agents had similar safety profiles.


Subject(s)
Contrast Media , Echocardiography , Fluorocarbons , Heart Diseases/diagnostic imaging , Adult , Aged , Emulsions , Endocardium/diagnostic imaging , Female , Heart Ventricles/diagnostic imaging , Humans , Injections, Intravenous , Male , Middle Aged , Sensitivity and Specificity , Single-Blind Method
17.
Chest ; 113(2): 482-91, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9498969

ABSTRACT

With the longer life expectancy of the population, calcific aortic stenosis has become a common cardiac problem in the elderly. When patients with moderate to severe aortic stenosis become symptomatic, the prognosis is usually poor in absence of valve replacement and sudden death is a feared complication. It has been hypothesized that malignant ventricular arrhythmias could be responsible for the high incidence of sudden death in symptomatic patients with aortic stenosis. The purpose of this review is to analyze the prevalence, the electrophysiologic mechanisms, and the possible role of ventricular arrhythmias in the development of symptoms and in the outcome of adult subjects with aortic stenosis.


Subject(s)
Aortic Valve Stenosis/complications , Arrhythmias, Cardiac/etiology , Calcinosis/complications , Ventricular Dysfunction/etiology , Adult , Aged , Aortic Valve/surgery , Arrhythmias, Cardiac/physiopathology , Death, Sudden, Cardiac/etiology , Electrocardiography , Forecasting , Humans , Hypertrophy, Left Ventricular/complications , Incidence , Life Expectancy , Outcome Assessment, Health Care , Prevalence , Prognosis , Syncope/complications , Ventricular Dysfunction/physiopathology
19.
J Am Coll Cardiol ; 31(1): 180-5, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9426038

ABSTRACT

OBJECTIVES: We tested the hypothesis that postoperative left ventricular (LV) systolic wall stress can be predicted from the change in LV diastolic dimension and ejection fraction (EF) after surgical correction of chronic mitral regurgitation (MR). We used a simple mathematic model to predict postoperative systolic stress from end-diastolic dimension and EF. The validity of this model was assessed using data from 21 patients undergoing mitral valve replacement (MVR) for chronic MR. BACKGROUND: The decline in EF after MVR for chronic MR is traditionally thought to be a consequence of a postoperative increase in afterload, caused by closure of a low resistance runoff into the left atrium. However, consideration of the Laplace relation suggests that afterload does not necessarily increase after the operation. METHODS: A spherical mathematical model of the left ventricle was used to define the relations between LV end-diastolic dimension, systolic wall stress and EF. To test the validity of this model, clinical and echocardiographic data were obtained from 21 patients with chronic MR before and 10 to 14 days after MVR. These echocardiographic data were examined with reference to plots derived from the mathematical model. RESULTS: Patients were categorized as those in whom end-diastolic dimension declined after the operation (group I, n = 15) and those with no reduction in end-diastolic dimension (group II, n = 6). Group I patients were subclassified into those undergoing MVR with chordal preservation (group Ia) and those undergoing MVR with chordal transection (group Ib). In groups Ib and II, there were significant reductions in EF (56 +/- 3% to 48 +/- 3% in group Ib and 50 +/- 2% to 40 +/- 3% in group II, both p < 0.05), but the changes in end-diastolic dimension and wall stress differed. In group Ib, end-diastolic dimension decreased and systolic wall stress was unchanged; in group II, end-diastolic dimension was unchanged and wall stress increased. In contrast, group Ia patients experienced a substantial reduction in end-diastolic dimension, no change in EF and a reduction in stress. The corresponding length-force-shortening coordinates closely approximate those predicted from a mathematic model relating end-diastolic dimension to EF and systolic wall stress. CONCLUSIONS: Concordant echocardiographic and mathematical model results indicate that postoperative changes in systolic stress are directly related to changes in chamber size and that LV afterload may fall when chordal preservation techniques are used in combination with MVR.


Subject(s)
Mitral Valve Insufficiency/surgery , Ventricular Function, Left , Chronic Disease , Female , Humans , Male , Middle Aged , Mitral Valve Insufficiency/physiopathology , Models, Cardiovascular , Myocardial Contraction , Postoperative Period , Stroke Volume
20.
Hypertension ; 30(4): 777-81, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9336372

ABSTRACT

Hypertensive patients with concentric remodeling (relative wall thickness > or = 0.45 and normal left ventricular [LV] mass index) may have poor outcomes. It is unclear whether systolic function abnormalities, shown to be present in some patients with concentric LV hypertrophy (increased LV mass index and relative wall thickness > or = 0.45), are also present in patients with concentric remodeling. To assess LV pump, chamber, and myocardial function in hypertensive men with concentric remodeling, clinical and echocardiographic data of 118 hypertensive men with concentric remodeling were compared with data from 104 hypertensive men with normal relative wall thickness and normal LV mass index. Chamber function was assessed by relating endocardial fractional shortening to end-systolic circumferential stress, myocardial function was assessed by relating midwall fractional shortening to circumferential stress, and pump performance was assessed by stroke volume (Teichholz method). Compared with hypertensive men with normal relative wall thickness, concentric-remodeling patients had lower stroke volume (84 +/- 20 versus 111 +/- 20 mL, P < .001). Endocardial shortening was no different between the two groups (38 +/- 7% versus 40 +/- 7%, P=NS), but midwall shortening was lower in patients with concentric remodeling (20 +/- 3% versus 22 +/- 3%, P < .001), despite lower end-systolic stress (81 +/- 25 versus 117 +/- 37 g/cm2, P < .001). Endocardial and midwall stress-shortening regression plots classified 28% and 42%, respectively, of the concentric remodeling patients below the fifth percentile of hypertensive patients with normal geometry. These data indicate that indexes of chamber and myocardial function are lower than those observed in hypertensive patients with normal geometry. Thus, indices of chamber, myocardial, and pump performance indicate potential abnormalities in systolic function in men with concentric remodeling.


Subject(s)
Hypertension/diagnostic imaging , Hypertension/physiopathology , Myocardium/pathology , Ventricular Function, Left/physiology , Aged , Echocardiography , Humans , Hypertension/complications , Male , Middle Aged , Myocardial Contraction/physiology , Obesity/complications , Systole/physiology
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