View clinical trials related to Ventricular Dysfunction.
Filter by:This prospective study evaluates the mechanisms of benefit of sacubitril/valsartan in a population of outpatients with heart failure with reduced ejection fraction, to investigate the relationship between the effects on left ventricular ejection fraction and volumes and noninvasively hemodynamic echo-derived parameters, as cardiac output and left ventricular filling pressure.
Coronavirus Disease 2019 (COVID-19) emerged in December 2019, and in mere few months has resulted in a pandemic of viral pneumonia. Substantial proportion of patients with COVID-19 have biochemical evidence of myocardial injuries during the acute phase. Possible mechanisms including acute coronary events, cytokine storm, and COVID-19 related myocarditis, have been postulated for the cardiac involvement in COVID-19. It is uncertain whether COVID-19 survivors are at risk cardiac dysfunction including cardiac arrhythmia and heart failure. The prospective screening study aims to evaluate the possible latent effects from COVID-19 in COVID-19 survivors. COVID-19 survivors 4-6 weeks after hospital discharge will be recruited from the Infectious Disease clinic, Queen Mary Hospital with standard 12-lead electrocardiogram, serum troponin, NT-proBNP, and standard transthoracic echocardiogram. The outcome measures include (1) new onset cardiac arrhythmia, (2) N Terminal (NT)-proBNP elevation above the diagnostic range of heart failure, and (3) newly detected left ventricular dysfunction.
The outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been declared a public health emergency of international concern. Hospitalized COVID-19-positive patients requiring ICU care is increasing along with the course of epidemic. A large number of these patients developed acute respiratory distress syndrome (ARDS) according to current data. However, the related hemodynamic characteristic has so far been rarely described.
Right ventricular failure (RVF) is an independent factor of mortality for many pulmonary diseases. Currently, RVF is defined as the incapacity of the RV to maintain the flow without dilating to use the Frank-Starling law (i.e., increase of the ejection volume associated to an increase of the preload). RVF is associated to RV systolic dysfunction which is conventionally defined as a decrease of the RV ejection fraction (RVEF) < 45%. In the intensive care unit (ICU), acute RVF is mainly due to the acute respiratory distress syndrome (ARDS), sepsis or septic shock, and less often to severe pulmonary embolism or RV infarction. The anatomical complexity of the RV precludes any geometrical assumption to estimate its volume, hence its ejection fraction (EF) using two-dimensional (2D) echocardiography. For this reason, the evaluation of RV systolic function is currently based on parameters used as surrogates of RVEF: fraction area change in 2D-mode, tricuspid annular plane systolic excursion (TAPSE) in M-mode, and maximal velocity of the systolic S' wave using tissue Doppler imaging. Real-time three-dimensional (3D) echocardiography now enables accurate on-line measurement of RV volume and provides at the bedside the non-invasive assessment of RVEF. 3D transthoracic echocardiography (TTE) has been validated to measure RV volume and RVEF compared to MRI which is the gold standard. However, 3D transesophageal echocardiography (TEE) has not yet been validated in this specific clinical setting, while 2D TEE is frequently used in ICU in ventilated and sedated patients. Accordingly, the diagnostic ability of 3D echocardiography to quantify RV systolic function in ICU patients with RVF of any origin is currently unknown.
In pulmonary arterial hypertension (PAH), progressive pulmonary vascular remodeling leads to supraphysiologic right ventricular (RV) afterload. Pharmacologic trials have shown that aggressive upfront treatment reversing pulmonary vascular remodeling successfully increases RV function and improves survival. To date, however, there are no proven treatments that target RV contractile function. Echocardiographic studies of RV dysfunction in the setting of pressure overload have demonstrated intra and interventricular dyssynchrony even in the absence of overt right bundle branch block (RBBB). Electrophysiologic studies of patients with chronic thromboembolic disease (CTEPH) at the time of pulmonary endarterectomy have shown prolongation of action potential and slowed conduction in the right ventricle which has correlated with echocardiographic measures of dyssynchrony. Cardiac MRI measures of RV strain in patients with PAH demonstrated simultaneous initiation of RV and left ventricular (LV) contraction, but delayed peak RV strain suggesting that interventricular dyssynchrony is a mechanical rather than electrical phenomenon. Prior studies of RV dysfunction in an animal model, computer model, congenital heart disease, and CTEPH have suggested acute hemodynamic benefits of RV pacing. However, RV pacing has not been studied in patients with PAH. Furthermore, it remains unclear if pacing particular regions of the RV can achieve a hemodynamic benefit and what cost this hemodynamic improvement may incur with regards to myocardial energetics and wall stress. Therefore, the investigators propose to examine RV electrical activation in PAH, map the area of latest activation, and then evaluate the hemodynamic and energetic effects of RV pacing in these patients.
Major lung resection is associated with high post-operative morbidity and mortality and significant long-term decreased functional capacity, especially due to cardiorespiratory complications. RV (Right Ventricle) ejection, pulmonary artery pressure and tone are tightly coupled. The RV is exquisitely sensitive to changes in afterload. When pulmonary vascular reserve is compromised RV ejection may be also compromised, increasing right atrial pressure and limiting maximal cardiac output. Acute increase in RV outflow resistance, as may occur with acute pulmonary embolism will cause acute RV dilatation and, by ventricular interdependence, markedly decreased LV (Left Ventricle) compliance, rapidly spiraling to acute cardiogenic shock and death. Most of the studies on RV function after lung resection are small and have found different results, and sometimes conflicting findings. As far as the investigators know, there are no data on the incidence of the RV dysfunction after major lung resection (pneumonectomy/bilobectomy) and it's not clear if there is some direct association between the RV dysfunction and post-operative complications. If so, early detection of RV dysfunction after major lung resection could provide the opportunity for interventional therapy with consequent possible improvement of these patients' prognosis.
A total of 130 patients with liver cirrhosis who fulfill the criteria of the study, and who have been found to have left ventricular diastolic dysfunction on a screening 2D echocardiography, will then be randomized by Block randomization technique, to two arms in a ratio 1:1(Group A) will receive carvedilol+ Ivabradine targeted therapy for heart rate reduction while Group B will receive Carvedilol alone; and the dosage of drug in the treatment arm will be titrated every week to achieve target heart rate of 50-60/ minute. Patients in the treatment arms, who are unable to tolerate carvedilol due to hypotension episodes, will be offered ivabradine alone to allow achievement of targeted heart rate reduction. All patients will be evaluated at 0,6, and 12 months. The end points will be clinical events, cardiac function improvement, renal function, and mortality.
Recovery of the left ventricular function is variable from one patient to another, thus assessment of cardiac function by measuring left ventricular ejection fraction using echocardiography is the most common in the daily clinical practice. However, this technique has limitation related with its intra- and interobserver variability. A recent technique, 2D speckle tracking for assessing global longitudinal strain, has been introduced to reduce the variability and potentially has a higher accuracy. Speckle tracking is a method which uses two dimensions recording for measuring quantity of movement of myocardium in several segments. Speckle-tracking echocardiography is a current noninvasive ultrasound imaging technique that allows for an objective and quantitative evaluation of global and regional myocardial function independently from the angle of insonation and from cardiac translational movements,
RV dysfunction has been associated with increased mortality in the ICU and cardiac surgical patients. Thus, early identification of RV dysfunction at less severe stages will allow for earlier intervention and potentially better patient outcomes. However, so far, no studies have reported prospectively the prevalence of abnormal RV pressure waveform during cardiac surgery and in the ICU. The investigator's primary hypothesis is that the prevalence of abnormal RV pressure waveform occurs in more than 50% of cardiac surgical patients throughout their hospitalization. Those patients with abnormal RV pressure waveform will be more prone to post-operative complications related to RV dysfunction and failure in the OR and ICU.
Study will investigate & compare the left ventricular remodeling & systolic function between two groups of ST-elevation myocardial infarction undergoing primary per-cutaneous coronary intervention applying ischemic post-conditioning to one of them.