Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Systolic Dysfunction”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,351 records · Page 75Linked to original sources
PubMed2002

The role of short- and long-axis function in determining late diastolic left ventricular filling in patients with hypertension: assessment by pulsed Doppler tissue imaging.

Left ventricular (LV) wall motion velocity during atrial systole is mediated by both transmitral flow and LV myocardial compliance at end-diastole. LV wall distensibility along the long- and short-axis during atrial systole and late diastolic LV filling may vary according to the remodeling of LV morphology. We measured LV wall motion velocities along the long and short axes using pulsed Doppler tissue imaging in 127 patients with hypertension to evaluate the relationship between the hemodynamic changes and LV morphology and to determine the role of both long- and short-axis function in late diastolic LV filling. Participants were classified into 3 groups according to LV dimension and end-diastolic wall thickness determined by M-mode echocardiography: group A (n = 62) without LV dilation or hypertrophy, group B (n = 55) with LV hypertrophy, and group C (n = 10) with LV dilation and systolic dysfunction. The time constant of the LV pressure decay during isovolumic diastole and the LV end-diastolic pressure were longest and greatest, respectively, in group C, compared with groups B and A. There were no significant differences in active left atrial emptying volume during atrial contraction determined by computerized echocardiographic 3-dimensional reconstruction among patient and control groups. The peak atrial systolic motion velocity of the LV posterior wall along the long axis was significantly lower in groups B and C, particularly in the latter group, than in group A. The peak atrial systolic motion velocity of the LV posterior wall along the short axis was greatest in group B and was lowest in group C compared with the other groups, respectively. The peak atrial systolic motion velocity of the LV posterior wall was greater along the long axis than the short axis in group A, but was less than the short axis in group B. In conclusion, the long- and short-axis function of the LV wall during atrial systole varies in patients with hypertension according to the severity of hemodynamic and morphologic abnormalities. The degree of LV wall expansion along the short axis is an important factor resulting from the atrial kick, and a determinant of its effectiveness.

Aged↗
PubMed2004

Eplerenone: a selective aldosterone receptor antagonist for patients with heart failure.

OBJECTIVE: To evaluate the pharmacology, pharmacokinetics, safety, and clinical use of eplerenone in heart failure (HF). DATA SOURCES: English-language MEDLINE searches were performed from 1966 to May 2004. Key words included eplerenone, aldosterone receptor antagonist, heart failure, myocardial infarction, left-ventricular dysfunction, and cost-effectiveness. Additional references were identified from bibliographies of selected articles. STUDY SELECTION AND DATA EXTRACTION: Human trials evaluating the efficacy, safety, and cost-effectiveness of aldosterone receptor antagonists in HF were evaluated. DATA SYNTHESIS: Eplerenone is the first selective aldosterone receptor antagonist. The drug is indicated to improve the survival of stable patients with left-ventricular systolic dysfunction (ejection fraction <40%) and clinical evidence of HF following acute myocardial infarction. Efficacy and safety in this population have been demonstrated in a large, randomized clinical trial. Eplerenone is associated with severe and sometimes life-threatening hyperkalemia. Patients with reduced renal function and diabetes, as well as those on other drugs that increase potassium levels, are at highest risk. Eplerenone is metabolized by the cytochrome P450 system and may interact with drugs that interfere with this system. A major advantage of eplerenone over the nonselective aldosterone receptor antagonist spironolactone is lack of binding to progesterone and androgen receptors, which is associated with drug-induced gynecomastia, breast pain, and impotence. CONCLUSIONS: The addition of eplerenone to traditional HF therapy has been shown to reduce morbidity and mortality in patients who develop left-ventricular dysfunction after acute myocardial infarction. Eplerenone's selectivity reduces sex hormone-related adverse effects. Despite these benefits, the overall cost-effectiveness has yet to be determined.

Animals↗
PubMed2005

Baseline echocardiographic characteristics of heart failure patients enrolled in a large European multicentre trial (CArdiac REsynchronisation Heart Failure study).

AIMS: Information on the prevalence and clinical, electrocardiographic and echocardiographic inter-relationships of mechanical dyssynchrony among patients with heart failure (HF) and left ventricular systolic dysfunction derives mainly from relatively small studies. The CARE-HF trial provides the opportunity to address these issues in a large population of patients with advanced HF. METHODS AND RESULTS: The CARE-HF trial enrolled patients with New York Heart Association (NYHA) class III or IV HF, with a QRS duration > or =120 ms, left ventricular (LV) ejection fraction (EF) < or =35% and LV end diastolic diameter > or =30 mm/m (height in m). Patients underwent a thorough echocardiographic evaluation, which included assessment of LV structure, systolic function, mitral inflow pattern, right ventricular (RV) dimensions and function, and interventricular mechanical delay (IVMD) as an index of interventricular dyssynchrony. Echocardiographic measurements were made in a Core Laboratory to ensure consistent quantitative analysis. Of the 813 patients enrolled, 735 had a baseline echocardiographic examination suitable for measurement. Overall patients had advanced LV dysfunction (mean EF 25.5%) but few had a restrictive mitral filling pattern (18%) and both the mean RV diameter and RV function were within normal limits. Interventricular dyssynchrony defined as IVMD >40 ms was present in 455 patients (62%). Clinical, electrocardiographic and standard echocardiographic variables were only loosely associated with IVMD. CONCLUSIONS: Interventricular dyssynchrony appears to be an independent characteristic of patients with advanced HF, and is poorly related to clinical, electrocardiographic or standard echocardiographic variable.

Aged↗
PubMed2001

Systolic and diastolic properties and myocardial blood flow in the heterotopically transplanted rat heart during acute cardiac rejection.

The aim of the study was to characterize the course of systolic and diastolic function, myocardial blood flow, and histologic changes during acute rejection in a model of heterotopic transplantation in rats. For this purpose isogenic Lewis-to-Lewis and allogenic DA (Dark Agouti)-to-Lewis rat cardiac transplants were studied 1 hour and 1, 3, and 5 days, respectively, after heterotopic intraabdominal transplantation. Myocardial tissue blood flow (MBF) was assessed by the hydrogen-clearance method. An implanted balloon was used to measure pressure-volume relations in the transplanted heart. Myocardial water content was determined at the end of the experiments, and histologic examinations were performed. The MBF recovered during the first day postoperatively in both groups and decreased again in the allogenic group after 3 and 5 days (p < 0.05); it remained stable in the isogenic group. Myocardial relaxation was already prolonged in the allogenic group after 3 days and deteriorated further. Left ventricular end-diastolic pressure progressively increased in the allogenic group, whereas it remained unchanged in the isogenic group up to 5 days. After recovery from ischemia, the left ventricular peak systolic pressure was stable in the isogenic group for the entire further observation period, but it significantly decreased in the allogenic group after 5 days (p < 0.05). Myocardial water content showed a significant increase in the allogenic group compared to that in the isogenic group after 5 days. In the allogenic group histologic examination confirmed mild to moderate rejection after 3 days and severe acute rejection after 5 days. Thus, after recovery from ischemia, mild to moderate cardiac rejection was associated with reduced MBF and impaired relaxation. In a typical sequence, generation of edema and impaired diastolic compliance were terminally followed by systolic dysfunction during severe rejection.

Animals↗
PubMed2000

Prognostic value of neurohormonal activation and cardiopulmonary exercise testing in patients with chronic heart failure.

We compared the value of plasma neurohormones and cardiopulmonary exercise testing for predicting long-term prognosis in patients with moderate congestive heart failure (CHF). We studied 264 consecutive patients with CHF due to left ventricular systolic dysfunction. Plasma atrial natriuretic peptide (ANP), norepinephrine, and endothelin-1 were measured at rest in all patients, who also underwent a symptom-limited maximal exercise with oxygen consumption (VO(2)) determination. After a median follow-up of 789 days, 52 deaths and 31 heart transplantations occurred, of which 4 were urgent. In an univariate analysis, New York Heart Association functional class, systolic blood pressure at rest, left ventricular end-diastolic diameter, left ventricular ejection fraction, peak VO(2), percent of predicted peak VO(2), plasma ANP, plasma norepinephrine, and plasma endothelin-1 were associated with survival without urgent heart transplantation. In a multivariate stepwise regression analysis, only plasma ANP (p = 0.0001), left ventricular ejection fraction (p = 0.007), and plasma norepinephrine (p = 0.035), but neither peak VO(2) nor percentage of predicted peak VO(2), were independent predictors of death or urgent heart transplantation. Determination of plasma ANP and norepinephrine provides additional independent information for long-term prognostic determination compared with exercise testing alone. Measurement of plasma neurohormones should therefore be considered routinely as a complementary or alternative tool for identifying high-risk patients with moderate CHF.

Atrial Natriuretic Factor↗
PubMed1994

[Changes in myocardial beta adrenergic receptors in left ventricular hypertrophy caused by barometric and volumetric overloads].

While most prior studies examined late stages of heart failure, we determined initial changes of beta-adrenergic receptors (beta-AR) during left ventricular chronic volume and pressure overload. We investigated right auricular (RA) and left ventricular (LV) beta-AR density (Bmax, fmoles/mg protein) and beta 1-AR percentage in two groups of patients undergoing valve replacement without LV systolic dysfunction (LV ejection fraction > or = 60%), with normal plasma catecholamine levels and echocardiography LV hypertrophy. These results were compared with the values of a control group, composed by 8 patients with mitral stenosis and 5 cardiac transplant donors, and the values of 5 patients undergoing heart transplantation because of end-stage idiopathic dilated cardiomyopathy. These results show that, before alteration of LV systolic function occurs, left ventricular chronic overload induces a selective down-regulation of LV beta 1-AR compensated by an increase in beta 2-AR. These variations may be due to LV hypertrophy induced by volume or pressure overload.

Catecholamines↗
PubMed1998

[Functional decoupling of left ventricular beta-adrenoceptor in a canine model of obesity-hypertension].

OBJECTIVE: To assess cardiac beta-adrenoceptors (beta-AR) in an obesity-hypertension model. METHODS: Six male beagle dogs (aged 35 +/- 5 months) receiving during 30 weeks a high-fat diet with 60% uncooked beef fat were compared to 6 normal beagle dogs. With right auricular and left ventricular samples we analysed cardiac beta-AR density through binding study using [125I]-cyanopindolol. beta 1 and beta 2 densities were obtained by competition with CGP 20712A. Affinity state of beta-AR was assessed by competition with isoproterenol. Noradrenaline plasma level was assayed by HPLC. Left ventricular mass (LV mass) was measured by echocardiography. Results are expressed as mean +/- SE. All comparisons were performed using a variance analysis (*: p < 0.05). RESULTS: Systolic blood pressure was significantly higher in obesses (245 +/- 8 vs 197 +/- 10 mmHg in controls). Diastolic blood pressure did not differed between both groups (93 +/- 3 vs 84 +/- 3 mmHg in controls). Noradrenaline plasma levels were similar in both groups (276 +/- 30 vs 235 +/- 50 pg/mL in controls). Obesses were characterized by higher LV mass (80 +/- 24 vs 67 +/- 15 g in controls*). Right auricular and left ventricular beta-AR densities were not different in obesses (57 +/- 6 and 67 +/- 4 fmoles/mg protein) and in controls (68 +/- 7 and 63 +/- 9 fmoles/mg protein). The beta 1-AR proportion was the same in obesses and controls in right auricule (63 +/- 4 vs 64 +/- 3% in controls) and left ventricule (59 +/- 3 vs 60 +/- 4% in controls). The proportion of beta-AR receptors in a high affinity state was similar in right auricular samples (69 +/- 4 vs 67 +/- 3%) in controls) but was significantly different in left ventricule (28 +/- 6 vs 74 +/- 6%) in controls). CONCLUSION: Left ventricular beta-adrenoceptors came under a specific desensibilisation independent of plasma noradrenaline levels. This functional decoupling of beta-adrenoceptors may account for the progressive systolic dysfunction of hypertensive cardiomyopathy.

Animals↗
PubMed1995

Left ventricular diastolic function after anthracycline chemotherapy in childhood: relation with systolic function, symptoms, and pathophysiology.

OBJECTIVES: To examine left ventricular (LV) diastolic function in patients previously treated with anthracycline drugs for childhood malignancy. To consider clinical relevance, relations with systolic dysfunction, and the pathophysiology of anthracycline cardiotoxicity. DESIGN: Cross sectional echocardiographic study of LV function. SETTING: Supraregional centre for paediatric cardiology, principal centre for the treatment of childhood malignancy in southwest England. PATIENTS: 226 of 236 patients surviving between 6.5 months and 17 (median 5.3) years from initial anthracycline treatment for childhood malignancy attended for clinical and echocardiographic examination. Cumulative anthracycline doses were between 50 and 750 (median 300) mg/m2. 22 patients had also received cardiac irradiation. METHODS: Detailed assessment of transmitral diastolic pulsed wave Doppler flow patterns along with LV dimensions and systolic function measured by M mode echocardiography. MAIN OUTCOME MEASURES: Peak early (E) and atrial (A) phase filling velocities and EA ratio, time and acceleration and deceleration to and from peak E velocity, velocity integrals and ratio, isovolumic relaxation time (IVRT), and heart rate were measured. Results were examined in relation to LV cavity and posterior wall dimensions and shortening fraction (SF), and compared with paired control data matched for body surface area. RESULTS: Eleven (5%) patients had abnormal effort tolerance. Fifty one (23%) had SF < 30% and SF was inversely correlated with cumulative dose and time from treatment. The relative risk of symptomatic cardiac failure was greatly increased by prior irradiation; > 60% of irradiated patients who received > 400 mg/m2 of anthracycline were symptomatic. Early diastolic filling was relatively normal or enhanced at low anthracycline doses or when SF was preserved, with a shorter IVRT and increased atrial phase filling. Early filling was reduced at higher doses or with reduced SF, with longer IVRT and a further increase in atrial phase filling. A more "restrictive" pattern of diastolic filling (with high E and low A velocities) was seen in some patients, particularly after cardiac irradiation. CONCLUSIONS: Significant abnormalities of diastolic function are associated with anthracycline induced cardiac damage. These are not linearly related to anthracycline dose but appear to reflect the underlying myocardial pathophysiology associated with anthracycline toxicity, which is not demonstrated by the standard M mode echocardiogram. Although the overall clinical significance of such diastolic dysfunction is uncertain, some individual abnormalities may have significant management and therapeutic implications.

Adolescent↗
PubMed2006

Left ventricular dysfunction and remodeling in streptozotocin-induced diabetic rats.

BACKGROUND: It is not fully clarified how diabetes mellitus (DM)-induced cardiac dysfunction is associated with histopathological changes of the heart in a long lasting period of DM. METHODS AND RESULTS: Eighteen weeks after a streptozotocin injection was given to Wistar - Kyoto rats (D rats), echocardiography and hemodynamic studies including the dobutamine infusion test were performed. After perfusion fixation, immunofluorescent staining and histopathology of the heart were analyzed, and analysis with electron microscopy was also conducted. Systolic blood pressure in the conscious state and left ventricular (LV) ejection fraction by 2-dimensional echocardiography were reduced in D rats. LV mechanical responses to dobutamine assessed by maximal LV pressure derivative (+LVdP/dt) also decreased with higher dobutamine doses in D rats. Although LV and right ventricular (RV) wall thickness were smaller in D rats, there were increased RV volumes, indicating LV and RV dilatational remodeling in D rats. The cardiomyocyte transverse diameter and actin staining in cardiomyocytes in both the LV and RV were significantly reduced, and capillary tortuosity and type IV collagen were increased, indicating microangiopathy in D rats. CONCLUSIONS: Advanced insulin-dependent DM incurred not only RV remodeling but also overt resting LV systolic dysfunction and decreased LV responsiveness to beta adrenergic stimulation with dilatational remodeling, accompanied by pathological changes of capillaries and cardiomyocytes including actin filaments.

Actin Cytoskeleton↗
PubMed2003

Microvascular disease relevance in the hypertension syndrome.

Hypertension is not an isolated problem. Co-morbidities of smoking, obesity, diabetes and dyslipidemia are all associated with microvascular disease (MVD) with abnormal PET scan and endothelial dysfunction. MVD may contribute to left ventricular hypertrophy (LVH) via an imbalance between hyperplasia and apoptotic signals. Digitalis and other anti-hypertensive agents have anti-apoptotic action and MVD blunting effects, respectively. Heart failure progression must then be based on the preservation of myocyte integrity. Indeed, altered contractility appears to be a consequence of rather than the cause of myocyte deterioration. LV systolic dysfunction improvement is already a late strategy. Furthermore, the efficacy of anti-hypertension therapy may be limited in restoring LV diastolic function. Recognition of the role of apoptosis and MVD may initiate a paradigm shift in clinical practice.

Antihypertensive Agents↗
PubMed1995

Cardiovascular manifestations in aluminium phosphide poisoning with special reference to echocardiographic changes.

Twenty five patients of aluminium phosphide poisoning along with clinical evidence of peripheral circulatory failure were studied. Chief symptoms noted were vomiting and epigastric pain though subsequently three patients developed respiratory distress. Sensorium was normal in most of the patients. Three patients developed pulmonary edema. Raised JVP, feeble heart sounds and S3 gallop beside tachy and bradycardia were other cardiovascular manifestations observed in these patients. In 80% of the patients, various types of ECG changes were observed. ST-T changes were observed in 40% of the patients. Echo-cardiography on day 1 revealed marked LV systolic dysfunction (mean ejection fraction-43.52 +/- 10.18% and mean fractional shortening 17.35 +/- 4.97%) in them whereas repeat echocardiography on day 5 indicated normalisation of these values (mean ejection fraction 71.64 +/- 8.61% and mean fractional shortening 34.35 +/- 8.23%). This might be because of direct toxic action of phosphine on myocardium and later when phosphine gets excreted either through lungs or kidney leads to improvement in LV systolic function.

Adult↗
PubMed2006

Aortic root dysfunctioning and its effect on left ventricular function in Ross procedure patients assessed with magnetic resonance imaging.

BACKGROUND: This study evaluated the diameters and distensibility of the aortic root as well as the degree of aortic regurgitation (AR) and its effect on left ventricular (LV) function in patients 8.2 +/- 3.1 years after they underwent the Ross procedure, with a comparison of these parameters between patients and matched healthy subjects. METHODS: Eighteen Ross procedure patients (16 male patients, age [mean +/- SD] 19.2 +/- 3.8 years) and 18 matched healthy subjects (16 male patients, age [mean +/- SD] 19.7 +/- 4.2 years) underwent magnetic resonance imaging. Measurements for diameters (at 4 levels) and the distensibility of the aortic root were performed using a steady-state free precession sequence. Aortic flow was assessed with a velocity-encoded phase-contrast sequence. Left ventricular systolic function was assessed with a gradient-echo sequence in the short-axis plane. Comparison of parameters was performed using the Mann-Whitney U test. Correlations between diameters, distensibility, AR fraction, and LV systolic function were expressed with Spearman rank correlation coefficients. Linear regression analysis was used to identify predictors of LV systolic dysfunction. RESULTS: Aortic root diameters were increased in Ross procedure patients as compared with healthy subjects (mean difference 6.3-11.6 mm, P < or = .02 at all 4 levels). Distensibility of the aortic root was lower in patients (1.9 +/- 1.1 vs 7.8 +/- 3.3 mm Hg(-1), P < .01). An AR fraction > 5% was present in 14 of the 18 patients (mean AR fraction 8% +/- 5% vs 1% +/- 1%, P < .01). Left ventricular ejection fraction was lower in patients (50% +/- 6% vs 57% +/- 6%, P < .01). Dilatation, decreased distensibility, and AR fraction were correlated with impaired LV systolic function (P < .05 for all). The AR fraction predicted impaired LV systolic function (P < .01). CONCLUSIONS: Magnetic resonance imaging shows dilatation and decreased distensibility of the aortic root, AR, and consequent impaired LV systolic function in patients after the Ross procedure.

Adolescent↗
PubMed2005

Contractile response and mitral regurgitation after temporary interruption of long-term cardiac resynchronization therapy.

AIMS: Cardiac resynchronization therapy (CRT) utilizing biventricular pacing (BVP) is a promising treatment modality for symptomatic patients with chronic left ventricular (LV) systolic dysfunction and intraventricular conduction delay. Clinical studies have shown short-term improvement in contractile function and mid-term improvement in clinical status with CRT. The objective of this study was to evaluate the haemodynamic consequences of temporary interruption of CRT after long-term stimulation. METHODS AND RESULTS: Twenty patients (16 men, 4 women) with LV dysfunction and New York Heart Association class III or IV heart failure, despite optimal medical therapy and a QRS interval of at least 120 ms, received a transvenous BVP system at the age of 66 (interquartile range, 61-69). Patients were studied after a median duration of 427 days (interquartile range, 281-563) of continuous CRT and again 72 h after cessation of BVP. Withdrawal of CRT resulted in a significant decline in maximal rate of LV systolic pressure rise from 711 mmHg/s (interquartile range, 640-816) to 442 mmHg/s (interquartile range, 389-582) (P=0.0001) and increases in mitral effective regurgitant orifice area from 4.8 mm(2) (interquartile range, 0.0-7.8) to 9.1 mm(2) (interquartile range, 5.7-13.3) (P=0.0001), mitral regurgitant volume from 7.8 mL (interquartile range, 0.0-11.5) to 16.0 mL (interquartile range, 10.7-20.8) (P=0.0001) and fraction from 13.8% (interquartile range, 0.0-19.2) to 27.7% (interquartile range, 14.6-34.0) (P=0.0002) determined by Doppler echocardiography. CONCLUSION: Cessation of long-term BVP leads to a decline in LV systolic performance and an increase in functional mitral regurgitation. These results indicate a sustained benefit of long-term CRT and support the notion to maintain CRT indefinitely.

Aged↗
PubMed1997

Left ventricular function after repeated episodes of ventricular fibrillation and defibrillation assessed by transoesophageal echocardiography.

BACKGROUND: Investigators studying the effects of cardioverter-defibrillators on left ventricular systolic function have given only minor attention to the diastolic effects. OBJECTIVES: The purpose of this study was to investigate the impact of repeated episodes of ventricular fibrillation and defibrillation on systolic function and diastolic filling of the left ventricle during non-thoracotomy implantation of a cardioverter-defibrillator. METHODS: Systolic function and diastolic filling of the left ventricle were assessed peri-operatively on a beat-by-beat basis using a transoesophageal echo-Doppler technique in 12 patients during > or = 4 episodes of ventricular fibrillation and defibrillation. Systolic function was assessed from the fractional area change and diastolic filling from the E/A ratio. Arterial blood pressure and the ECG were recorded continuously. RESULTS: Blood pressure and heart rate did not change significantly throughout the procedure. The systolic function, similarly, was not significantly affected; the only changes were seen in the first two beats after defibrillation when the mean fractional area increased from 0.2 +/- 0.01 to 0.4 +/- 0.02 and 0.3 +/- 0.02, respectively (P < 0.001). Diastolic filling was, however, impaired as reflected by a decrease in the E/A ratio from 2.6 +/- 0.5 before to 1.6 +/- 0.4 (P < 0.01) after repeated threshold tests. CONCLUSIONS: While the combined ischaemic and electrical trauma caused by repeated episodes of ventricular fibrillation and defibrillation during the implantation of a cardioverter-defibrillator did not cause any systolic dysfunction, diastolic filling was significantly impaired.

Adult↗
PubMed1994

Heart failure due to chronic experimental aortic regurgitation.

Previously reported experimental models of aortic regurgitation generally have manifested normal systolic performance and have not developed heart failure [Magid et al. Am. J. Physiol. 263 (Heart Circ. Physiol. 32): H226-H233, 1992]. To determine whether more severe chronic experimental aortic regurgitation would generate systolic malperformance, heart failure, and emulate the human disease process, 11 New Zealand White rabbits underwent surgical induction of aortic regurgitation and 5 control animals underwent sham operation. Doppler echocardiography was performed serially for up to 3 yr, and pathological studies were performed at necropsy. Left ventricular internal dimension at end diastole increased 80% (P < 0.00002) and left ventricular weight increased 250% (P < 0.0002) in aortic regurgitant rabbits (regurgitant fraction 52 +/- 13%) compared with baseline values. Six of 11 aortic regurgitant animals died with pathological evidence of congestive heart failure at 1.5 +/- 0.8 yr postoperatively; 2 of these developed severe systolic malperformance, manifest as fractional shortenings of 15 and 19% at 1.6 and 1.7 yr, respectively. Five of 11 aortic regurgitant animals survived until killed at 2.9 +/- 0.1 yr. Thus moderate-to-severe chronic aortic regurgitation in rabbits frequently results in heart failure and systolic dysfunction and may usefully model chronic aortic regurgitation and heart failure in humans.

Animals↗
PubMed2003

Clinical and transthoracic echocardiographic predictors of abnormal transesophageal findings in patients with suspected cardiac source of embolism.

BACKGROUND: Approximately 20% of cerebral infarctions are caused by a cardiac source of embolism. Although transesophageal echocardiography (TEE) is a valuable tool for evaluating patients with suspected cardioembolism, its use should be more selective. OBJECTIVE: We attempted to determine whether risk factors derived from the clinical, ECG, and transthoracic echocardiogram (TTE) would make TEE use more selective and increase its yield. METHODS: We retrospectively reviewed the records of 108 patients with suspected embolic stroke who had undergone TEE evaluation. We defined the presence of left atrial appendage spontaneous contrast (LAASC), left atrial appendage thrombus (LAAT), patent foramen ovale (PFO), or intraatrial septal aneurysm (IASA) as TEE endpoints suggestive of cardioembolism. We evaluated the association between the TEE endpoints and (1) age greater than 60 years, (2) the presence of atrial flutter (AFl) or atrial fibrillation (AF) on ECG, (3) left ventricular (LV) dysfunction by TTE (mild, LVEF < 40%; severe, LVEF < 25%), and (4) left atrial (LA) size > 4 cm also determined by TTE. The statistical analysis performed was one-way analysis of variance controlling for interactions between different risk factors and the endpoints. RESULTS The strongest independent predictors for the presence of LAASC or LAAT were age greater than 60 years, presence of AFl/AF, and LV systolic dysfunction. There was no association between any of the risk factors with the presence of PFO or IASA. CONCLUSION: This study demonstrates that clinical characteristics, ECG, and TTE findings can help to better select stroke patients for TEE. Future larger studies are needed to provide more supporting data.

Adult↗
PubMed2002

Advances in implantable cardioverter defibrillators.

Implantable cardioverter defibrillators (ICDs) have become an important therapeutic modality for patients who have had a cardiac arrest or are at risk for life-threatening ventricular arrhythmias. Clinical trials have confirmed the role of the ICD for patients with sustained ventricular arrhythmias and have expanded the indications to include patients with coronary artery disease, left ventricular dysfunction, nonsustained ventricular tachycardia, and inducible ventricular tachycardia. Numerous technologic advances in ICDs have resulted in decreased size, greater ease of placement, and increased functionality. Important advancements have been made in the effectiveness of arrhythmia classification and electrogram storage. Dual-chamber ICDs have become increasingly sophisticated with rate-adaptive sensors. Biventricular pacing is being combined with ICD function in patients with heart failure, systolic dysfunction, and QRS widening. Future advances in devices will likely lead to improved arrhythmia classification, more advanced automated features, and additional features including more sophisticated sensors and biventricular pacing systems.

Arrhythmias, Cardiac↗
PubMed1998

Pulsed Doppler echocardiographic study of left ventricular diastolic function in patients with idiopathic dilated cardiomyopathy.

Dilated cardiomyopathy is basically regarded as a disease of left ventricular systolic dysfunction. There are only a few studies evaluating diastolic function in patients with dilated cardiomyopathy. To assess the LV diastolic function, 25 patients with idiopathic dilated cardiomyopathy and 20 age and sex matched normal subjects were studied with transmitral spectral tracings derived from pulsed Doppler echocardiography. All cardiomyopathy patients were in New York Heart Association class III to IV with dilated left ventricles and reduced systolic function (mean ejection fraction of 36.6 +/- 6.7 Vs 65 +/- 6 in normal subjects, p < 0.001). Patients with cardiomyopathy demonstrated an increased ratio of early to late diastolic velocity (E/A) (1.89 +/- 0.59 Vs 1.50 +/- 0.27 m/sec, p < 0.05), short deceleration time (E-E/2) (57.05 +/- 13.36 Vs 70.20 +/- 16.56 msec, p < 0.01) and short isovolumic relaxation time (IVRT) (53.5 +/- 22.7 Vs 72 +/- 12 msec, p < 0.05) as compared to normal subjects. The early filling fraction (EFF) was higher (0.71 +/- 0.11 Vs 0.66 +/- 0.06, p < 0.05) and atrial filling fraction (AFF) was lower (0.28 +/- 0.11 Vs 0.33 +/- 0.06, p < 0.05) in cardiomyopathy patients than in normal subjects. Our observations in a select group of dilated cardiomyopathy patients with advanced disease demonstrate a restrictive pattern on pulsed Doppler echocardiography.

Adult↗