Cardiac resynchronization therapy : determinants of patient outcome and emerging indications

CRT has evolved as a successful treatment strategy in selected patients with drug refractory heart failure. Evidence of large clinical trials established the beneficial effects of CRT in addition to optimal medical treatment on both morbidity and mortality. Nonetheless, about 30% of patients do not demonstrate response to CRT. Several patient characteristics have a strong influence on both response at 6 months follow-up and prognosis during long-term follow-up. In addition to these patient characteristics, the position of the LV pacing lead in relation to the site of latest activation and potential scar tissue may have a great influence on outcome. Integration of patient characteristics, LV lead position with information on LV dyssynchrony and scar tissue may help to improve patient selection and response to CRT. It is not unlikely that the favorable effects of CRT will be extended to other patient groups in the coming years. These groups include asymptomatic (NYHA class I) patients, patients with a narrow QRS complex (<120 ms) or patients with heart failure but preserved LVEF (__45%). CRT also seems to improve other conditions frequently observed in patients with heart failure. The improved LV systolic function induced by CRT increases cerebral blood flow and also results in stabilization of renal function. Finally, patients with severe functional MR and high operative risk also derive benefit from CRT. Perhaps CRT may one day be used as an effective treatment strategy in these patient groups.UBL - phd migration 201

Clinical Characteristics and Management of Coronary Artery Perforations

BACKGROUND: Coronary artery perforation (CAP) is a potentially lethal complication of percutaneous coronary intervention. We report on the incidence, clinical characteristics, and management of iatrogenic coronary perforations based on an 11-year single-center experience. METHODS AND RESULTS: From February 9, 2005, through November 20, 2016, 150 CAP cases were identified from our percutaneous coronary intervention database of 21 212 procedures (0.71%). Mean age of CAP patients was 66±11 years, and 62.7% were male. Treated lesion type was B2/C in 94.6%, and 31.3% were chronic total occlusions. Nonworkhorse guidewires were applied in 74.3%. CAP types were Ellis type I in 2.9%, Ellis type II in 40.4%, Ellis type III in 54.8%, and Ellis type III cavity spilling in 1.9%. CAP treatment was conservative (including prolonged balloon inflation) in 73.3%. Covered stents, coiling, and fat embolization were used in 24.0%, 0.7%, and 2.0%, respectively. Pericardiocentesis for tamponade was required for 72 patients (48.0%), of whom 28 were initially unrecognized. Twelve patients (12.7%) required emergency cardiac surgery to alleviate tamponade. Periprocedural myocardial infarction occurred in 34.0%, and in-hospital all-cause mortality was 8.0%. All-cause mortality accrued to 10.7% at 30 days and 17.8% at 1 year. CONCLUSIONS: CAP is a rare complication of percutaneous coronary intervention, but morbidity and mortality are considerable. Early recognition and adequate management are of paramount importance

Long-term outcome in patients treated with first- versus second-generation drug-eluting stents for the treatment of unprotected left main coronary artery stenosis

Objective and background: The study aim is to provide long-term clinical outcome after percutaneous coronary intervention (PCI) for unprotected left main coronary arteries (ULMCA) stenosis with the first-generation (1st-gen) drug-eluting stents (DES) in comparison to 2nd-gen DES, since t

Cardiac resynchronization therapy : determinants of patient outcome and emerging indications

CRT has evolved as a successful treatment strategy in selected patients with drug refractory heart failure. Evidence of large clinical trials established the beneficial effects of CRT in addition to optimal medical treatment on both morbidity and mortality. Nonetheless, about 30% of patients do not demonstrate response to CRT. Several patient characteristics have a strong influence on both response at 6 months follow-up and prognosis during long-term follow-up. In addition to these patient characteristics, the position of the LV pacing lead in relation to the site of latest activation and potential scar tissue may have a great influence on outcome. Integration of patient characteristics, LV lead position with information on LV dyssynchrony and scar tissue may help to improve patient selection and response to CRT. It is not unlikely that the favorable effects of CRT will be extended to other patient groups in the coming years. These groups include asymptomatic (NYHA class I) patients, patients with a narrow QRS complex (<120 ms) or patients with heart failure but preserved LVEF (__45%). CRT also seems to improve other conditions frequently observed in patients with heart failure. The improved LV systolic function induced by CRT increases cerebral blood flow and also results in stabilization of renal function. Finally, patients with severe functional MR and high operative risk also derive benefit from CRT. Perhaps CRT may one day be used as an effective treatment strategy in these patient groups

Technology trajectories and the selection of optimal R and D project sequences

Given a set of R&D projects drawing on the same underlying technology, a technology trajectory refers to the order in which projects are executed. Due to their technological interdependence, the successful execution of one project can increase a firm's technological capability, and help to efficiently and effectively develop other projects from this set. In this paper, we present a model for determining the optimal sequence for performing such projects. Based on Huchzermeier and Loch's real-option value model, we demonstrate that accounting for interproject learning and discount rates has: 1) a positive effect on the maximum option value that different project sequences can achieve; and 2) the maximum value of the technology trajectory is particularly sensitive to the selection of the first project

Exploring the effectiveness of pursuing competing technologies in parallel projects during predevelopment

Prior research has studied the effectiveness of parallel projects in the research and development stages. However, it has ignored predevelopment, which R&D intensive firms generally distinguish as a separate stage lodged between research and development. Predevelopment focuses on activities and decisions to select, from a subset of related technologies, the best option for a product application. Parallel projects are often a means of speeding up this process by actively pursuing learning spillovers. This paper develops assumptions about learning potential and then uses a real option model to test the trade-off between the higher costs and benefits of this parallel project approach. We compare outcomes for predevelopment using the same approach under research and development conditions, respectively. The results reveal that, when moving from research to development, the effectiveness of pursuing competing technologies in parallel projects first increases and then decreases, with a maximum positive result in predevelopment. The results also show that learning spillovers can compensate for the higher investment costs. Data from an empirical case support our findings

Critical Appraisal of the Use of Cardiac Resynchronization Therapy Beyond Current Guidelines

Cardiac resynchronization therapy (CRT) is an effective treatment for patients with drug-refractory, chronic heart failure. Multiple single-center and multicenter studies have shown significant reductions in left ventricular (LV) volumes and an increase in LV systolic function. More importantly, CRT reduces mortality and morbidity during long-term follow-up. Current guidelines consider CRT as a Class I indication for heart failure patients in New York Heart Association (NYHA) functional class III to IV with depressed LV ejection fraction = 120 ms). However, the benefits of this therapy could possibly be extended to selected subgroups of patients who do not fulfill these criteria. These subgroups include patients with mildly symptomatic heart failure and patients with a narrow QRS complex (<120 ms). Results from recent multicenter controlled clinical trials including heart failure patients in NYHA functional class I to II or with a narrow QRS complex are equivocal. Although expanding CRT to patients with a narrow QRS complex seems currently not likely, the benefits of CRT in mildly symptomatic patients are more evident. Perhaps attenuation of disease progression will prove to be a successful new treatment strategy in heart failure patients in the future. In addition, multimodality cardiac imaging will allow optimizing responder rate in patients undergoing CRT according to current guidelines. (J Am Coll Cardiol 2010;56:754-62) (C) 2010 by the American College of Cardiology FoundationCardiac Dysfunction and Arrhythmia

Value of the surface electrocardiogram in detecting right ventricular dilatation in the presence of left bundle branch block

Cardiolog

QRS fusion complex analysis using wave interference to predict reverse remodeling during cardiac resynchronization therapy

Cardiolog