At least 25-30% of patients with a permanent implantable left ventricular assist device (LVAD) experience right ventricular failure; therefore, an implantable biventricular assist system (BiVAS) with small centrifugal pumps is being developed. Many institutions are focusing and developing a control system for a left ventricular assist system (LVAS) with rotary ...

We looked at the benefits and complications of a home-based exercise programme in patients with ischaemic and idiopathic dilated cardiomyopathy. Twenty-four patients with left ventricular end-diastolic dimension >6.5 cm and fractional shortening <25% entered a cross-over trial of 8 weeks training versus 8 weeks rest. Echocardiography, electrocardiogram and cardiopulmonary exercise ...

We tested the hypothesis that lowering the level of cyclic GMP would have positive functional effects on isolated rabbit ventricular myocytes regardless of the basal cyclic GMP level. Cell shortening data were collected with a video detector; O(2) consumption data were obtained with a Clark electrode; intracellular cyclic GMP levels ...

OBJECTIVE: This study focuses on variation in brain morphology associated with supernumerary X chromosome and Klinefelter syndrome (KS). Using an unselected birth cohort of KS subjects and high-resolution MRI, the authors investigated the neuroanatomic consequences of the 47,XXY karyotype in the presence and absence of exogenous testosterone supplementation. METHODS: Regional ...

The aim of the present investigation was to compare the hemodynamic and thermal responses to a 30-min aerobic exercise between middle- or old-aged patients with normal left ventricular function and those with left ventricular dysfunction. Constant-load sitting ergometer exercise of approximately 90% of the subject's oxygen uptake (VO2) at the ...

BACKGROUND: Left ventricular enlargement with normal systolic function is common in asymptomatic relatives of patients with familial dilated cardiomyopathy, many of whom progress to overt dilated cardiomyopathy at follow up. OBJECTIVE: To examine maximal and submaximal gas exchange variables of cardiopulmonary exercise testing in asymptomatic relatives with left ventricular enlargement. ...

We describe a patient presenting clinical features of corticobasal degeneration (CBD), including reflex myoclonus in the left upper limb. This patient complained of a marked worsening of involuntary movements in the left upper limb after exercise. We analysed the electrophysiological characteristics of myoclonus in the basal state and after a ...

OBJECTIVE: To determine whether pharmacological stress leads to prolonged but reversible left ventricular dysfunction in patients with coronary artery disease, similar to that seen after exercise. DESIGN: A randomised crossover study of recovery time of systolic and diastolic left ventricular function after exercise and dobutamine induced ischaemia. SUBJECTS: 10 patients ...

The effects of inotropically active agents on the left ventricular force-interval relation are a potential determinant of their clinical utility and safety. However, little information is available concerning the effects of noncatecholamine positive inotropic agents on this relation. Therefore this study compared the short-term effects of digoxin and milrinone on ...

Three mule deer and 4 mule deer/white-tailed deer hybrids were immobilized in a crossover study with carfentanil (10 microg/kg) + xylazine (0.3 mg/kg) (CX), and medetomidine (100 microg/kg) + ketamine (2.5 mg/kg) (MK). The deer were maintained in left lateral recumbency for 1 h with each combination. Deer were immobilized ...

"Sudden cardiac death" in seemingly healthy, active, and asymptomatic people has always been a tragic fact and is now occurring more frequently. Thus, the preventive detection of "subjects at risk" becomes a priority. A traditional resting electrocardiogram can sometimes give useful indications. Fifty-two competitive triathletes were compared with 22 control ...

A 15-year-old girl, who was previously in good health, suddenly collapsed while jogging. Immediate cardiopulmonary resuscitation (CPR) was initiated, and she arrived at our hospital 13 minutes later. The ventricular fibrillation (VF) on admission was reverted to sinus rhythm 18 minutes after collapse by the second cardioversion. The echocardiogram revealed ...

There are several important links between aerobic exercise performance and the diastolic phase of the cardiac cycle. During acute exercise, diastolic function must be augmented in order for left ventricular filling to match increased left ventricular output, i.e., cardiac output. This challenges the myocardium because the shortened duration of diastole ...

OBJECTIVES: We sought to determine whether objective tests of antiarrhythmic drug efficacy could produce favorable short- and long-term outcomes in a family with idiopathic malignant ventricular arrhythmias. BACKGROUND: In 1973 a family presented with a history of several generations of syncopal spells and sudden death. Some individuals had nonspecific electrocardiographic ...

OBJECTIVES: To determine whether the heart rate (HR) response to exercise in 21 highly trained cyclists (mean (SD) age 25 (3) years) was related to their heart dimensions. METHODS: Before performing an incremental exercise test involving a ramp protocol with workload increases of 25 W/min, each subject underwent echocardiographic evaluation ...

BACKGROUND: Measuring the transmitral flow velocity with Doppler echocardiography is a useful method for evaluating left ventricular diastolic function. However, there are few data regarding the effect of posture during exercise on transmitral flow velocity. METHODS: The transmitral flow velocity with pulsed-wave Doppler echocardiography was measured during supine and upright ...

To assess the effects of 6 months intervention with +ramipril on resting and post exercise left ventricular function in patients with stable ischaemic heart disease and preserved left ventricular systolic function. METHODS and Patients (n=98, age 65+/-9 years, 37% women) were randomized to double-blind treatment with ramipril 5 mg. day(-1)(n=32), ...

OBJECTIVE: To study subclinical left ventricular dysfunction in anemic children. SETTING: Hospital. SUBJECTS: The study population consisted of 52 cases of anemia (16 mild, 14 moderate, 22 severe) and 20 normal age and height matched children aged between 7-12 years. METHODS: These children were subjected to Echocardiography on Ascuson XP ...

PURPOSE: The purpose of the present investigation was to examine differences that may exist in maximal and submaximal exercise gas exchange parameters and their use in differentiating pathological and physiological left ventricular hypertrophy. METHODS: Exercise gas exchange responses were measured on-line during a maximal ramping cycle-ergometer exercise test in 10 ...

In this study we compared the efficacy of Doppler and atrioventricular plane motion echocardiography in detecting the changes in left ventricular function caused by moderate-intensity training. Fifty-nine healthy men and women (aged 40-68 years) were divided into either a group of walkers (n = 32) or controls (n = 27). ...

PURPOSE: In the current era of efficient use of personnel and cost containment, the use of non-physicians in selected roles previously occupied exclusively by physicians has become increasingly prevalent. Traditionally, physicians have directly supervised graded exercise testing of patients with chronic heart failure. The purpose of this prospective pilot investigation ...

OBJECTIVES: We tested the hypothesis that acute intravenous verapamil acutely enhances aerobic exercise performance in healthy older individuals in association with a combined reduction of ventricular systolic and arterial vascular stiffnesses. BACKGROUND: Age-related vascular stiffening coupled with systolic ventricular stiffening may limit cardiovascular reserve and, thus, exercise performance in aged ...

To investigate whether during cardiac hypertrophy changes occur in contractile protein composition and in mechanical and energetic properties of the myocardium, contractile protein composition, isometric force and adenosine triphosphate (ATP) consumption were studied in control and hypertrophied guinea-pig hearts. Cardiac hypertrophy was induced by adding minoxidil (120 or 200 mg/l) ...

99Tcm-labelled myocardial perfusion tracers allow simultaneous assessment of myocardial perfusion and left ventricular function using ECG-gated SPET. The aim of this study was to evaluate left ventricular performance during exercise by means of ECG-gated myocardial perfusion SPET. After the administration of 99Tcm-tetrofosmin (555-740 MBq), eight healthy volunteers aged 27-49 years ...

Transcoronary alcohol ablation (TAA) therapy of septal hypertrophy was recently proposed as a therapeutic modality for obstructive hypertrophic cardiomyopathy (HC). However, questions remain about the effect of TAA on exercise performance. We performed a time-course analysis of exercise capacity and exercise hemodynamics in 20 patients with symptomatic obstructive HC after ...

Arrhythmogenic right ventricular cardiomyopathy is emerging as a relatively common cause of exercise-induced sudden death in the young. The diagnostic criteria at autopsy are, however, not fully established, leading to both over- and underdiagnosis. We report a young man and a young woman dying suddenly of right ventricular dysplasia during ...

A 3-year-old girl presented with a febrile illness complicated by right ventricular outflow tract tachycardia, which persisted after resolution of the presumed viral infection. The tachycardia was intermittent, but was significantly exacerbated by exercise. Radiofrequency ablation (RFA) of the ectopic focus was successfully performed and the child remains free of ...

We tested the ability of cycle ergometer exercise echocardiography to detect cases of occult cor pulmonale among 25 patients with chronic obstructive pulmonary disease (COPD). The M-mode echocardiographic ventricular septal motion, left ventricular shape determined by short-axis two-dimensional (2-D) echocardiography, and right and left ventricular pressure curves were recorded at ...

We present a patient with exercise-induced paroxysmal atrial fibrillation who was eventually scheduled for a Cox-maze operation due to persistence of his complaints of fatigue, impaired exercise tolerance, and predominantly exercise-related irregular palpitations despite treatment with several antiarrhythmic drugs. A preoperative exercise stress test without antiarrhythmic or negative chronotropic drugs, ...

BACKGROUND: Exercise testing has long been employed in patients with hypertrophic cardiomyopathy (HCM), although concerns have constantly been expressed regarding its safety. This study reviews a large number of exercise tests performed in a community-based population with HCM, in terms of safety and clinical utility. METHODS: We analyzed a total ...

OBJECTIVE: To examine the relation between patterns of ventricular remodelling and haemodynamic and neurohormonal variables, at rest and during symptom limited exercise, in the year following acute myocardial infarction in patients not receiving angiotensin converting enzyme (ACE) inhibitors. DESIGN: A prospective observational study. Patients: 65 patients recruited following hospital admission ...

BACKGROUND: The present study was designed to assess the impact of left ventricular hypertrophy (LVH) independent of hypertension on the presence of silent myocardial ischemia and arrhythmia, as well as on systolic and diastolic function in otherwise healthy elderly men. METHODS AND RESULTS: Twenty apparently healthy normotensive subjects with LVH ...

OBJECTIVES: The objective of this study was to examine the association between exercise capacity and echocardiographic indexes of atrial and ventricular function and size in patients with beta-thalassemia major. BACKGROUND: In patients with beta-thalassemia major, the assessment of cardiac function with echocardiography alone does not always correspond to their functional ...

The purpose of this study was to establish whether bilateral symmetry exists during wheelchair propulsion in the elbow movement pattern of trained wheelchair racers. Seven endurance-trained wheelchair racers volunteered to participate in the study. Each subject was recorded by two-dimensional video analysis while pushing on a single-roller wheelchair ergometer at ...

OBJECTIVES: We investigated whether endogenous pulmonary big endothelin has arrhythmogenic properties under normal conditions and in heritable hyperlipidemia. BACKGROUND: Endothelin (ET), one of the most potent vasoconstrictors, is known to induce ventricular arrhythmias. It is unclear, however, whether its precursor, big endothelin, released from the lung, contributes to arrhythmogenesis. METHODS: ...

AIMS: Most studies in chronic heart failure have only included patients with marked left ventricular systolic dysfunction (i.e. ejection fraction < or =0.35), and patients with mild left ventricular dysfunction are usually excluded. Further, exercise capacity strongly depends on age, but age-adjustment is usually not applied in these studies. Therefore, ...

Measures of left ventricular function during exercise provide information that is more accurate than the exercise ECG in the diagnosis of coronary artery disease, supportive of the data provided by myocardial perfusion studies, and of great prognostic significance. We review basic methods for evaluating left ventricular function during exercise and ...

Patients with hypertrophic cardiomyopathy (HC) die suddenly. Proposed risk factors for sudden cardiac death (SCD) in HC are youth, a family history of SCD, syncope, and ventricular tachycardia. Hemodynamic variables have not convincingly proved to be risk factors for SCD. Therefore, this study was designed to examine predictors of SCD ...

OBJECTIVE: To investigate the recovery process of exercise induced diastolic dysfunction in heart failure, using Doppler echocardiographic techniques. DESIGN AND PATIENTS: Transmitral flow velocity profiles and standard noninvasive haemodynamic indices were obtained serially over seven days after symptom limited bicycle exercise tests in 18 patients with dilated cardiomyopathy and eight ...

In a pilot study at 14 patients with coronary heart disease (CHD) and left-ventricular dysfunction (left ventricular enddiastolic volume [LVEDV] > or = 100 ml), who actively participated in an ambulatory cardiac sports group, left ventricular endsystolic volume (LVESV), LVEDV and duration of exercise were analyzed by echocardiographic and ergometric ...

Delivery of inappropriate therapy of implantable cardioverter defibrillators (ICD) due to inaccurate arrhythmia detection represents a major clinical problem. Different arrhythmia detection criteria such as the "stability" of the cycle length or the suddenness of "onset" of tachycardia have been implemented in ICD software to prevent inappropriate therapy. The new ...

A case of exercise-induced idiopathic ventricular tachycardia (VT) arose from the left ventricular outflow tract. The QRS morphology of the VT was Rs pattern in V1 and R pattern in the lateral leads with inferior axis. The pacing at the superior interventricular septum near the mitral anulus produced the best ...

BACKGROUND: In patients with left ventricular dysfunction one of the aims of therapy may be to improve functional capacity. This study compared the improvement of functional capacity in response to medical therapy with that caused by revascularization. METHODS: Fifty-two patients with severe left ventricular dysfunction were divided into groups with ...

STUDY OBJECTIVES: Pulmonary hypertension is the most important complication in patients with atrial septal defect (ASD), but its role in limiting exercise has not been examined. This study sought to evaluate exercise performance in adults with ASD and determine the contribution of elevated pulmonary artery pressure in limiting exercise capacity. ...

To evaluate the late effects of chronic pulmonary regurgitation against the putative benefits from the current surgical trend of primary repair of tetralogy of Fallot with a transannular patch in infancy, 10 patients > 10 years after early primary repair and 7 matched normal controls underwent exercise stress test and ...

BACKGROUND: Aortic prosthetic valves with superior hemodynamic performance are associated with more complete regression of left ventricular hypertrophy and better left ventricular function postoperatively. The near normal function of the pulmonary autografts at rest is well documented, however, exercise data has been seldom reported. The purpose of this study is ...

For conversion of atrial fibrillation to sinus rhythm and management of ventricular arrhythmias, antiarrhythmic drugs were frequently used. However, the effects of antiarrhythmic drugs on exercise performance and on the variability of ventricular rate were not available. This study included 37 patients who had chronic atrial fibrillation complicated with symptomatic ...

Left ventricular failure is not considered an important feature in cystic fibrosis (CF), but abnormalities of left ventricular function have been reported. Except for a few cases of heart failure in neonates with CF, there is no evidence of a primary disorder of the myocardium in patients with CF. Since ...

Ventricular arrhythmias are considered to be related to left ventricular (LV) dysfunction. ACE inhibitors though improve LV function their beneficial role on exercise-induced ventricular arrhythmias is not established. To study the effects of ACE inhibitors on exercise capacity vis-a-vis their role on exercise-induced ventricular arrhythmias, 25 patients of congestive heart ...

OBJECTIVE: To evaluate the clinical effects and the changes in cardiac performance of high- and low-dose captopril compared to placebo in patients with chronic symptomatic aortic regurgitation (AR), and/or mitral regurgitation (MR). PATIENTS AND METHODS: We randomized patients into three groups, placebo (Group 1), incremental daily doses of 50 mg ...