Hemodynamics of Mechanical Circulatory Support Burkhoff, Daniel, MD, PhD; Sayer, Gabriel, MD; Doshi, Darshan, MD ...
Journal of the American College of Cardiology,
12/2015, Letnik:
66, Številka:
23
Journal Article
Recenzirano
Odprti dostop
Abstract An increasing number of devices can provide mechanical circulatory support (MCS) to patients with acute hemodynamic compromise and chronic end-stage heart failure. These devices work by ...different pumping mechanisms, have various flow capacities, are inserted by different techniques, and have different sites from which blood is withdrawn and returned to the body. These factors result in different primary hemodynamic effects and secondary responses of the body. However, these are not generally taken into account when choosing a device for a particular patient or while managing a patient undergoing MCS. In this review, we discuss fundamental principles of cardiac, vascular, and pump mechanics and illustrate how they provide a broad foundation for understanding the complex interactions between the heart, vasculature, and device, and how they may help guide future research to improve patient outcomes.
Highlights • Models of heart and vascular properties have evolved over the past century. • These models have been coupled to yield comprehensive cardiovascular simulations. • Simulations help explain ...certain aspects of the pathophysiology of heart failure (HF). • Simulations have successfully predicted the effects of certain types of HF therapies. • Further validation may expand the role of simulations to help customize HF therapies.
Previous trials have shown that among high-risk patients with aortic stenosis, survival rates are similar with transcatheter aortic-valve replacement (TAVR) and surgical aortic-valve replacement. We ...evaluated the two procedures in a randomized trial involving intermediate-risk patients.
We randomly assigned 2032 intermediate-risk patients with severe aortic stenosis, at 57 centers, to undergo either TAVR or surgical replacement. The primary end point was death from any cause or disabling stroke at 2 years. The primary hypothesis was that TAVR would not be inferior to surgical replacement. Before randomization, patients were entered into one of two cohorts on the basis of clinical and imaging findings; 76.3% of the patients were included in the transfemoral-access cohort and 23.7% in the transthoracic-access cohort.
The rate of death from any cause or disabling stroke was similar in the TAVR group and the surgery group (P=0.001 for noninferiority). At 2 years, the Kaplan-Meier event rates were 19.3% in the TAVR group and 21.1% in the surgery group (hazard ratio in the TAVR group, 0.89; 95% confidence interval CI, 0.73 to 1.09; P=0.25). In the transfemoral-access cohort, TAVR resulted in a lower rate of death or disabling stroke than surgery (hazard ratio, 0.79; 95% CI, 0.62 to 1.00; P=0.05), whereas in the transthoracic-access cohort, outcomes were similar in the two groups. TAVR resulted in larger aortic-valve areas than did surgery and also resulted in lower rates of acute kidney injury, severe bleeding, and new-onset atrial fibrillation; surgery resulted in fewer major vascular complications and less paravalvular aortic regurgitation.
In intermediate-risk patients, TAVR was similar to surgical aortic-valve replacement with respect to the primary end point of death or disabling stroke. (Funded by Edwards Lifesciences; PARTNER 2 ClinicalTrials.gov number, NCT01314313.).
Although preoperative renal dysfunction (RD) is associated with increased mortality and morbidity after surgical aortic valve replacement, its impact on clinical outcomes after transcatheter aortic ...valve replacement (TAVR) is less defined.
TAVR patients in the PARTNER (Placement of Aortic Transcatheter Valves) trial with a calculable glomerular filtration rate (GFR) using the Modification of Diet in Renal Disease equation were included. Patients were divided into three groups: GFR >60 mL/min (none/mild RD), GFR 31 to 60 mL/min (moderate RD), and GFR ≤30 mL/min (severe RD). Operative characteristics and clinical outcomes were analyzed. Cox regression models were used to determine multivariable predictors of 1-year all-cause mortality.
A total of 2,531 inoperable or high surgical risk patients from the PARTNER trial and continued access registries had a calculable GFR level: 767 (30%) had normal renal function or mild RD, 1,473 (58%) had moderate RD, and 291 (12%) presented with severe RD. The mean Society of Thoracic Surgeons Predicted Risk of Mortality for the cohort was 11.5%, and it was highest in those with severe RD (13.8%). Patients with severe RD were more often women with a higher prevalence of diabetes. Patients with severe RD had the highest incidence of 30-day and 1-year all-cause mortality and rehospitalization. The 30-day rate of death from any cause was 10.7% in the severe RD group versus 6.0% in the moderate and mild RD groups (p = 0.01). The 1-year rate of death from any cause was 34.4% in the severe RD group versus 21.5% in the moderate RD and 20.8% in the none/mild RD groups (adjusted hazard ratio HR 2.24, p < 0.0001 for severe versus none/mild; adjusted HR 1.14, p = 0.24 for severe versus moderate). Other significant predictors of 1-year all-cause mortality included lower body mass index, frailty, the transapical approach, a lower ejection fraction, oxygen-dependent chronic obstructive pulmonary disease, liver disease, and male sex.
Preoperative severe RD is a significant predictor for 1-year mortality in TAVR patients. Careful risk stratification by the heart team is required in patients with severe preprocedural RD.
Summary The management of aortic valve disease has been improved by accurate diagnosis and assessment of severity by echocardiography and advanced imaging techniques, efforts to elicit symptoms or ...objective markers of disease severity and progression, and consideration of optimum timing of aortic valve replacement, even in elderly patients. Prevalence of calcific aortic stenosis is growing in ageing populations. Conventional surgery remains the most appropriate option for most patients who require aortic valve replacement, but the transcatheter approach is established for high-risk patients or poor candidates for surgery. The rapid growth of transcatheter aortic valve replacement has been fuelled by improved technology, evidence-based clinical research, and setting up of multidisciplinary heart teams. Aortic regurgitation can be difficult to diagnose and quantify. Left ventricular dysfunction often precedes symptoms, needing active surveillance by echocardiography to determine the optimum time for aortic valve replacement. Development of transcatheter approaches for aortic regurgitation is challenging, owing to the absence of valvular calcification and distortion of aortic root anatomy in many patients.
Abstract Background Although ischemic coronary artery disease (CAD) is the most common etiology of heart failure (HF), the extent to which patients with new-onset HF actually undergo an ischemic ...work-up and/or revascularization is not well defined. Objectives This study sought to analyze the patterns of testing for ischemic CAD and revascularization in patients with new-onset HF. Methods This was a retrospective cohort study using Truven Health MarketScan Commercial and Medicare databases from 2010 to 2013. The occurrence of noninvasive and invasive ischemic CAD testing and revascularization procedures were examined among patients with new inpatient HF diagnoses during the index hospitalization and within 90 days of admission. Results Among 67,161 patients identified with new-onset HF during an inpatient hospitalization, only 17.5% underwent testing for ischemic CAD during the index hospitalization, increasing to 27.4% at 90 days. Among patients with new-onset HF, only 2.1% underwent revascularization during the index hospitalization for HF; by 90 days, the revascularization rate had increased to 4.3%. Of the tests performed for ischemic CAD, stress testing (nuclear stress testing or stress echocardiography) was performed in 7.9% of new-onset HF patients during the index hospitalization (14.6% within 90 days), whereas coronary angiography was performed in 11.1% of patients during the index hospitalization (16.5% within 90 days). In adjusted analyses, HF patients carrying a baseline diagnosis of CAD had greater odds of noninvasive ischemic testing (odds ratio: 1.25; 95% confidence interval: 1.17 to 1.33; p < 0.0001), as well as invasive ischemic testing (odds ratio: 1.93; 95% confidence interval: 1.83 to 2.05; p < 0.0001), at the index hospitalization than those without baseline CAD. Conclusions The majority of patients hospitalized for new-onset HF did not receive testing for ischemic CAD either during hospitalization or within 90 days, which suggests significant underutilization of ischemic CAD assessment in new-onset HF patients.
Background Cardiogenic shock ( CS ) following acute myocardial infarction ( AMI ) portends a poor prognosis. Both venoarterial extracorporeal membrane oxygenation ( VA - ECMO ) and a percutaneous ...ventricular assist device ( pVAD ) provide hemodynamic support for patients with CS, but little is known about the best device for this population. We sought to compare outcomes of AMI patients treated with these devices. Methods and Results Consecutive patients with CS following AMI from April 2015 to March 2017 were enrolled prospectively if they received either device for AMI -related CS . If patients received both devices, they were analyzed according to the first used. The primary outcome was all-cause mortality. In total, 51 patients received VA - ECMO or pVAD following AMI ; 20 received VA - ECMO, and 31 received pVAD . The mean age was 62.1±10.1 years, and 39 (76.5%) were men. Twenty-four (47.1%) patients were ultimately supported by both devices simultaneously (20 pVAD -first, 4 VA - ECMO -first). Patients treated with pVAD or VA - ECMO were similar in baseline characteristics at initial device insertion except that the latter were on more vasopressors and were more likely to have an intra-aortic balloon pump. Seventeen (33.3%) had recent cardiopulmonary resuscitation, mean lactate was 4.86±3.96 mmol/L, and mean cardiac index was 1.70±0.42 L/min per m
. Of the 28 (54.9%) patients surviving to discharge, 11 had received VA - ECMO first and 17 had pVAD first ( P=0.99). Survival at 1 and 2 years did not differ significantly between device groups ( P=0.42). Conclusions Following AMI -related CS , pVAD - and VA - ECMO -treated patients had similar outcomes. The use of both devices simultaneously was common, with almost half of patients in persistent CS after first device deployment.
Abstract Objectives The purpose of this study was to determine the safety and effectiveness of the SAPIEN XT versus SAPIEN systems (Edwards Lifesciences, Irvine, California) in patients with ...symptomatic, severe aortic stenosis (AS) who were not candidates for surgery. Background Transcatheter aortic valve replacement (TAVR) has become the standard of care for inoperable patients with severe, symptomatic AS. In the PARTNER (Placement of Aortic Transcatheter Valves) IB trial, a reduction in all-cause mortality was observed in patients undergoing TAVR with the balloon-expandable SAPIEN transcatheter heart valve compared with standard therapy, but the SAPIEN valve was associated with adverse periprocedural complications, including vascular complications, major bleeding, and paravalvular regurgitation. The newer, low-profile SAPIEN XT system was developed to reduce these adverse events. Methods A total of 560 patients were enrolled at 28 sites in the United States from April 2011 to February 2012. Patients were randomized to receive the SAPIEN or SAPIEN XT systems. The primary endpoint was a nonhierarchical composite of all-cause mortality, major stroke, and rehospitalization at 1 year in the intention-to-treat population, assessed by noninferiority testing. Pre-specified secondary endpoints included cardiovascular death, New York Heart Association functional class, myocardial infarction, stroke, acute kidney injury, vascular complications, bleeding, 6-min walk distance, and valve performance (by echocardiography). Results Both overall and major vascular complications were higher at 30 days in patients undergoing TAVR with SAPIEN compared with SAPIEN XT (overall: 22.1% vs. 15.5%; p = 0.04; major: 15.2% vs. 9.5%; p = 0.04). Bleeding requiring blood transfusions was also more frequent with SAPIEN compared with SAPIEN XT (10.6% vs. 5.3%; p = 0.02). At 1-year follow-up, the nonhierarchical composite of all-cause mortality, major stroke, or rehospitalization was similar (37.7% SAPIEN vs. 37.2% SAPIEN XT; noninferiority p value <0.002); no differences in the other major pre-specified endpoints were found. Conclusions In inoperable patients with severe, symptomatic AS, the lower-profile SAPIEN XT is noninferior to SAPIEN with fewer vascular complications and a lesser need for blood transfusion. (The PARTNER II Trial: Placement of AoRTic TraNscathetER Valves; NCT01314313 )
Background
The influence of coronary artery disease (CAD) on clinical and echocardiographic outcomes after transcatheter aortic valve replacement (TAVR) is still controversial. We sought to evaluate ...the impact of CAD severity as measured by the SYNTAX score (SS) on patients undergoing TAVR.
Methods and Results
A total of 377 patients who underwent TAVR in 2 high‐volume centers in North America were included in our retrospective analysis. A blinded angiographic core laboratory calculated the SS on all available coronary angiograms with the use of quantitative coronary analysis. Patients were stratified into 4 groups: (1) no CAD (SS=0); (2) low SS (SS between 1 and 22); (3) intermediate SS (SS between 23 and 32); and (4) high SS (SS ≥33). Patients who had undergone percutaneous coronary intervention within 6 months prior to TAVR were separated into 2 categories based on their residual SS (<8 and ≥8). Patients with previous coronary artery bypass grafting (CABG) were divided into 2 groups: (1) low CABG SS and (2) high CABG SS. The primary end point was a composite of all‐cause mortality, myocardial infarction, and stroke. At 30 days and 1 year, both the presence and the severity of CAD had no impact on the rate of the combined primary end point and on all‐cause mortality, cardiovascular mortality, and myocardial infarction. Patients with less complete revascularization (residual SS ≥8 versus residual SS <8 and low CABG SS versus high CABG SS, had similar rates of the combined primary end point, all‐cause mortality, cardiovascular mortality, MI, and stroke, at both 30 days and 1 year.
Conclusions
In our core laboratory–validated study, neither the severity of CAD nor completeness of revascularization after percutaneous coronary intervention or CABG were associated with clinical outcomes after TAVR, at both 30 days and 1 year.
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