Project description:Over the past decade, left ventricular assist device (VAD) therapy has become more prevalent and increasingly safe. Severe complications, such as VAD pump thrombosis and outflow graft obstruction, are rare, yet still associated with high morbidity and mortality. Clinical presentation, VAD alarm and log files, laboratory analysis, and non-invasive cardiac imaging are crucial for establishing the correct diagnosis and determining clinical management. Early intervention is critical to prevent adverse cardiac remodelling or VAD pump failure.
Project description:BackgroundLeft ventricular assist device (LVAD) implantation significantly impacts on a recipient's symptoms and quality of life. Capturing their experiences and post implant journey is an important part of clinical practice, research and device design evolution. Patient reported outcome measures (PROMs) are a useful tool for capturing that experience. However, patient reported outcome measures need to reflect recipients' experiences. Discussions with a patient partner group found that none of the frequently used cardiology PROMs captured their unique experiences.AimsTo capture the experiences and important issues for LVAD recipients. Develop a conceptual map of domains and items that should be reflected in patient reported outcomes.MethodsGroup concept mapping (GCM) web-based software was used to remotely capture and structure recipients' experiences across a wide geographical area. GCM is a semi-quantitative mixed method consisting of 3 stages: item generation, item sorting and rating (importance, relevance and frequency). Patient partners were involved in all aspects of the study design and development.Results18 LVAD recipients consented to take part. 101 statements were generated and multi-dimensional scaling, and hierarchical cluster analysis identified 9 clusters. Cluster themes included: Activities, Partner/family support, Travel, Mental wellbeing, Equipment and clothing, Physical and cognitive limitations, LVAD Restrictions, LVAD Challenges and positive impact of the LVAD (LVAD Positives). LVAD Positives were scored highest across all the rating variables, e.g., frequency (2.85), relevance (2.44) and importance (2.21). Other domains rated high for importance included physical and cognitive limitations (2.19), LVAD restrictions (2.11), Partner/family support (2.02), and Equipment and clothing (2.01).ConclusionOnline GCM software facilitated the inclusion of geographically dispersed recipients and provided useful insights into the experiences of LVAD recipients. The conceptual framework identifies important domains and items that should be prioritised and included in patient reported outcomes in future research, LVAD design evolution, and clinical practice.
Project description:Molecular analysis of the effect left ventricular assist device (LVAD) support has on congestive heart failure patients. Keywords = Congestive heart failure, left ventricular assist device, eNOS, gene, dimethylarginine dimethylaminohydrolase Keywords: other
Project description:AimsCurrently, there is limited data on prognostic indicators after insertion of percutaneous ventricular assist device (PVAD) in the treatment of cardiogenic shock (CS). This study evaluated the prognostic role of cardiac power output (CPO) ratio, defined as CPO at 24 h divided by early CPO (30 min to 2 h), in CS patients after PVAD.Methods and resultsConsecutive CS patients from the QEH-PVAD Registry were followed up for survival at 90 days after PVAD. Among 121 consecutive patients, 98 underwent right heart catheterization after PVAD, with CPO ratio available in 68 patients. The CPO ratio and 24-h CPO, but not the early CPO post PVAD, were significantly associated with 90-day survival, with corresponding area under curve in ROC analysis of 0.816, 0.740, and 0.469, respectively. In multivariate analysis, only the CPO ratio and lactate level at 24 h remained as independent survival predictors. The CPO ratio was not associated with age, sex, and body size. Patients with lower CPO ratio had significantly lower coronary perfusion pressure, worse right heart indices, and higher pulmonary vascular resistance. A lower CPO ratio was also significantly associated with mechanical ventilation and higher creatine kinase levels in myocardial infarction patients.ConclusionIn post-PVAD patients, the CPO ratio outperformed the absolute CPO values and other haemodynamic metrics in predicting survival at 90 days. Such a proportional change of CPO over time, likely reflecting native heart function recovery, may help to guide management of CS patients post-PVAD.
Project description:Durable mechanical circulatory support (MCS) systems are established therapy option in patients with end-stage heart failure, with increasing importance during the last years due to donor organ shortage. Left ventricular assist devices (LVADs) are traditionally implanted through median sternotomy (MS). However, improvement in the pump designs during the last years led to evolvement of new surgical approaches that aim to reduce the invasiveness of the procedure. Numerous reports and studies have shown the viability and possible advantages of less-invasive approach compared to the sternotomy approach. The less invasive implant strategies for LVADs, while vague in definition, are characterized by minimizing surgical trauma and if possible, cardio-pulmonary bypass related complications. Usually it involves minimizing or completely avoiding sternal trauma, avoiding heart luxation while simultaneously leaving the major part of pericardium intact. There is no consensus between the centers regarding the ideal approach for LVAD implantation. Some centers, like our center, perform by default VAD implantation using less invasive approach in almost all patients and some centers use only sternotomy approach. The aim of this review article is to shed light on the currently available less invasive options of LVAD implantation, with particular focus on the centrifugal pumps, and their possible advantages compared to traditional sternotomy approach.
Project description:Background Cardiogenic shock (CS) is a complex syndrome associated with high morbidity and mortality. In recent years, many US hospitals have formed multidisciplinary shock teams capable of rapid diagnosis and triage. Because of preexisting collaborative systems of care, hospitals with left ventricular assist device (LVAD) programs may also represent "centers of excellence" for CS care. However, the outcomes of patients with CS at LVAD centers have not been previously evaluated. Methods and Results Patients with CS were identified in the 2012 to 2014 National Inpatient Sample. Clinical characteristics, revascularization rates, and use of mechanical circulatory support were analyzed in LVAD versus non-LVAD centers. The association between hospital type and in-hospital mortality was examined using multivariable logistic regression models. Of 272 075 hospitalizations, 26.0% were in LVAD centers. CS attributable to causes other than acute myocardial infarction represented most cases. In-hospital mortality was lower in LVAD centers (38.9% versus 43.3%; P<0.001). In multivariable analysis, the odds of mortality remained significantly lower for hospitalizations in LVAD centers (odds ratio, 0.89; P<0.001). In patients with CS secondary to acute myocardial infarction, revascularization rates were similar between LVAD and non-LVAD centers. The use of intra-aortic balloon pump (18.7% versus 18.8%) and Impella/TandemHeart (2.6% versus 1.9%) was similar between hospital types, whereas extracorporeal membrane oxygenation was used more frequently in LVAD centers (4.3% versus 0.2%; P<0.001). Conclusions Risk-adjusted mortality was lower in patients with CS who were hospitalized at LVAD centers. These centers likely represent specialized, shock team capable institutions across the country that may be best suited to manage patients with CS.
Project description:ObjectivesThe main aim was a systematic evaluation of the current evidence on outcomes for patients undergoing right ventricular assist device (RVAD) implantation following left ventricular assist device (LVAD) implantation.MethodsThis systematic review was registered on PROSPERO (CRD42019130131). Reports evaluating in-hospital as well as follow-up outcome in LVAD and LVAD/RVAD implantation were identified through Ovid Medline, Web of Science and EMBASE. The primary endpoint was mortality at the hospital stay and at follow-up. Pooled incidence of defined endpoints was calculated by using random effects models.ResultsA total of 35 retrospective studies that included 3260 patients were analyzed. 30 days mortality was in favour of isolated LVAD implantation 6.74% (1.98-11.5%) versus 31.9% (19.78-44.02%) p = 0.001 in LVAD with temporary need for RVAD. During the hospital stay the incidence of major bleeding was 18.7% (18.2-19.4%) versus 40.0% (36.3-48.8%) and stroke rate was 5.6% (5.4-5.8%) versus 20.9% (16.8-28.3%) and was in favour of isolated LVAD implantation. Mortality reported at short-term as well at long-term was 19.66% (CI 15.73-23.59%) and 33.90% (CI 8.84-59.96%) in LVAD respectively versus 45.35% (CI 35.31-55.4%) p ⩽ 0.001 and 48.23% (CI 16.01-80.45%) p = 0.686 in LVAD/RVAD group respectively.ConclusionImplantation of a temporary RVAD is allied with a worse outcome during the primary hospitalization and at follow-up. Compared to isolated LVAD support, biventricular mechanical circulatory support leads to an elevated mortality and higher incidence of adverse events such as bleeding and stroke.
Project description:To characterize the irregularity of the spectrum of a signal, spectral entropy and its variants are widely adopted measures. However, spectral entropy is invariant under the permutation of the power spectrum estimations on a predefined grid. This erases the inherent order structure in the spectrum. To disentangle the order structure and extract meaningful information from raw digital signal, a novel analysis method is necessary. In this paper, we tried to unfold this order structure by defining descriptors mapping real- and vector-valued power spectrum estimation of a signal into a scalar value. The proposed descriptors showed its potential in diverse problems. Significant differences were observed from brain signals and surface electromyography of different pathological/physiological states. Drastic change accompanied by the alteration of the underlying process of signals enables it as a candidate feature for seizure detection and endpoint detection in speech signal. Since the order structure in the spectrum of physiological signal carries previously ignored information, which cannot be properly extracted by existing techniques, this paper takes one step forward along this direction by proposing computationally efficient descriptors with guaranteed information gain. To the best of our knowledge, this is the first work revealing the effectiveness of the order structure in the spectrum in physiological signal processing.
Project description:BackgroundPatients with acute myocardial infarction (AMI) complicated by acute heart failure or cardiogenic shock have high mortality with conventional management.ObjectivesThis study evaluated outcomes of patients with AMI who received durable ventricular assist devices (VAD).MethodsPatients in the INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) registry who underwent VAD placement in the setting of AMI were included and compared with patients who received VAD for non-AMI indications.ResultsVAD were implanted in 502 patients with AMI: 443 left ventricular assist devices; 33 biventricular assist devices; and 26 total artificial hearts. Median age was 58.3 years, and 77.1% were male. At implantation, 66% were INTERMACS profile 1. A higher proportion of AMI than non-AMI patients had pre-operative intra-aortic balloon pumps (57.6% vs. 25.3%; p < 0.01), intubation (58% vs. 8.3%; p < 0.01), extracorporeal membrane oxygenation (17.9% vs. 1.7%, p < 0.01), cardiac arrest (33.5% vs. 3.3%, p < 0.01), and higher-acuity INTERMACS profiles. At 1 month post-VAD, 91.8% of AMI patients were alive with ongoing device support, 7.2% had died on device, and 1% had been transplanted. At 1-year post-VAD, 52% of AMI patients were alive with ongoing device support, 25.7% had been transplanted, 1.6% had left VAD explanted for recovery, and 20.7% had died on device. The AMI group had higher unadjusted early phase hazard (hazard ratio [HR]: 1.24; p = 0.04) and reduced late-phase hazard of death (HR: 0.57; p = 0.04) than the non-AMI group did. After accounting for established risk factors, the AMI group no longer had higher early mortality hazard (HR: 0.89; p = 0.30), but it had lower late mortality hazard (HR: 0.55; p = 0.02).ConclusionsPatients with AMI who receive VAD have outcomes similar to other VAD populations, despite being more critically ill pre-implantation. VAD therapy is an effective strategy for patients with AMI and acute heart failure or shock in whom medical therapy is failing.