Sagar N. Doshi

Impella ventricular support in clinical practice: Collaborative viewpoint from a European expert user group

Mechanical circulatory support represents an evolving field of clinical research and practice. Currently, several cardiac assist devices have been developed but, among different institutions and countries, a large variation in indications for use and device selection exists. The Impella platform is an easy to use percutaneous circulatory support device which is increasingly used worldwide. During 2014, we established a working group of European physicians who have collected considerable experience with the Impella device in recent years. By critically comparing the individual experiences and the operative protocols, this working group attempted to establish the best clinical practice with the technology. The present paper reviews the main theoretical principles of Impella and provides an up-to-date summary of the best practical aspects of device use which may help others gain the maximal advantage with Impella technology in a variety of clinical settings.

Standalone balloon aortic valvuloplasty: Indications and outcomes from the UK in the transcatheter valve era

We sought to characterize UK‐wide balloon aortic valvuloplasty (BAV) experience in the TAVI era.

Contemporary clinical outcomes of patients treated with or without rotational coronary atherectomy - An analysis of the UK central cardiac audit database

INTRODUCTION Rotational atherectomy (RA) is widely used for treating calcified coronary lesions. Clinical data however remain limited. METHODS We assessed outcome and survival among patients undergoing percutaneous coronary intervention (PCI) with or without RA in the UK between September 2007 and March 2011. RESULTS Data from 221,669 percutaneous coronary intervention (PCI) procedures were analysed; 2152 patients (0.97%) underwent RA (RA+); the remainder underwent conventional PCI (RA-). RA+ patients were older (71.7±9.6 vs. 64.1±12.8 year; p<0.001), and had a higher incidence of diabetes (26.4% vs. 18.0%; p<0.001), hypertension, (61.9% vs. 49.4%; p<0.001), peripheral vascular disease (9.9% vs. 4.2%, p<0.001), cerebrovascular disease (5.5% vs. 3.4%, p<0.001), renal impairment (3.4% vs. 1.5%, p<0.001) and poor left ventricular function (11.4% vs. 4.3%,p<0.001). Procedural success was lower among RA+ patients (90.3% vs 94.6%; p<0.001) and procedural complications were more frequent (9.7% vs 5.4%; p<0.001). After 2.4±1.2 years follow-up, unadjusted Cox proportional hazard modeling demonstrated poorer survival for RA+ patients (HR 2.21, 95%CI 1.97-2.49; p<0.0001). This disadvantage remained after adjustment for adverse variables (HR 1.26, 95%CI 1.11-1.44; p=0.0004) and following propensity analysis. There was evidence however of improved survival for RA+ patients with left main stem disease (HR 0.52, 95%CI 0.35-0.75, p<0.0001), and peripheral vascular disease (HR 0.65, 95%CI 0.43-0.98, p<0.0005). CONCLUSIONS Rotational atherectomy was undertaken in patients with higher pre-procedural risk. Medium term survival was worse among patients undergoing rotational atherectomy, and this survival disadvantage remained after correction for available adverse factors. Rotational atherectomy however remains clinically useful for patients with calcified coronary lesions.

Folate improves endothelial function in patients with coronary heart disease

Abstract Elevated plasma homocysteine is associated with increased cardiovascular risk but it remains unproven that the effect is directly causal. Folate and homocysteine metabolism are closely linked such that administration of folic acid in doses ranging from 0.2–10 mg/day lowers plasma total homocysteine (tHcy) by up to 25%. Folic acid has been widely advocated as a therapy which may reduce cardiovascular risk, but the clinical benefit remains as yet unproven and the choice of dose remains unclear. The effect of folic acid on endothelial function has been investigated in patients with proven coronary heart disease (CHD) by measuring flow-mediated dilatation (FMD) in the brachial artery. Oral folic acid (5 mg/day) markedly enhances endothelial function (FMD) and lowers homocysteine. Studies of the acute effects of folic acid have shown that this improvement occurs within the first 2–4 hours following the first dose, at which times there was no significant reduction in plasma tHcy. Administration of 5-methyltetrahydrofolate directly into the brachial artery markedly enhances FMD, an effect that is blocked by monomethyl arginine (LNMMA), suggesting that the effects of folate are mediated by nitric oxide. This Review summarises studies which show that pharmacological doses of folate markedly enhance endothelial function in patients with CHD. The discordance with changes in plasma homocysteine suggests that these effects may occur by mechanisms distinct from homocysteine lowering.

Improving endothelial vasomotor function

The vascular endothelium is a confluent, cellular monolayer that lines the entire vascular compartment at the interface between blood and the vessel wall. This “organ” possesses complex endocrine and paracrine functions and is intimately concerned in controlling vasomotor tone and preventing atherosclerosis and thrombosis.1 Indeed, endothelial dysfunction plays a key part in the pathogenesis and progression of atherosclerosis.2 An important and relatively recently discovered endothelial product is nitric oxide, a simple, highly reactive gas previously known as endothelium-derived relaxing factor. Endothelial nitric oxide itself possesses potent antiatherogenic properties, inhibits platelet aggregation, and regulates vascular tone.1 Bioavailable nitric oxide may be increased either by enhancing its production or by reducing its inactivation—for example, by reactive oxygen species, which are thought to damage the endothelium and promote atherosclerosis. Indirect measurement of bioavailable nitric oxide, through its vasodilating properties, is an extensively investigated surrogate of endothelial (vasomotor) function in clinical and experimental studies. In this …

Automated cardiopulmonary resuscitation using a load-distributing band external cardiac support device for in-hospital cardiac arrest: A single centre experience of AutoPulse-CPR

BACKGROUND Poor quality cardiopulmonary resuscitation (CPR) predicts adverse outcome. During invasive cardiac procedures automated-CPR (A-CPR) may help maintain effective resuscitation. The use of A-CPR following in-hospital cardiac arrest (IHCA) remains poorly described. AIMS & METHODS Firstly, we aimed to assess the efficiency of healthcare staff using A-CPR in a cardiac arrest scenario at baseline, following re-training and over time (Scenario-based training). Secondly, we studied our clinical experience of A-CPR at our institution over a 2-year period, with particular emphasis on the details of invasive cardiac procedures performed, problems encountered, resuscitation rates and in-hospital outcome (AutoPulse-CPR Registry). RESULTS Scenario-based training: Forty healthcare professionals were assessed. At baseline, time-to-position device was slow (mean 59 (±24) s (range 15-96s)), with the majority (57%) unable to mode-switch. Following re-training time-to-position reduced (28 (±9) s, p<0.01 vs baseline) with 95% able to mode-switch. This improvement was maintained over time. AutoPulse-CPR Registry: 285 patients suffered IHCA, 25 received A-CPR. Survival to hospital discharge following conventional CPR was 28/260 (11%) and 7/25 (28%) following A-CPR. A-CPR supported invasive procedures in 9 patients, 2 of whom had A-CPR dependant circulation during transfer to the catheter lab. CONCLUSION A-CPR may provide excellent haemodynamic support and facilitate simultaneous invasive cardiac procedures. A significant learning curve exists when integrating A-CPR into clinical practice. Further studies are required to better define the role and effectiveness of A-CPR following IHCA.

Feasibility and efficacy of the 2.5 L and 3.8 L impella percutaneous left ventricular support device during high-risk, percutaneous coronary intervention in patients with severe aortic stenosis.

Assessment of the feasibility and outcomes of the 2.5 L and 3.8 L Impella cardiac pump in patients with severe aortic stenosis (AS) and left ventricular impairment undergoing percutaneous revascularization (PCI) with or without balloon aortic valvuloplasty (BAV).Objective Assessment of the feasibility and outcomes of the 2.5 L and 3.8 L Impella cardiac pump in patients with severe aortic stenosis (AS) and left ventricular impairment undergoing percutaneous revascularization (PCI) with or without balloon aortic valvuloplasty (BAV). Methods We reviewed the clinical and procedural findings from a consecutive series of unselected patients with severe AS who underwent PCI during Impella support. In addition, we describe novel “balloon-assist” techniques that allowed implantation of Impella into the left ventricle (LV) when initial unassisted attempts failed. Results Five patients with severe AS were identified (four males, age 78.2 years, aortic valve area (AVA) 0.6 cm2, left ventricular ejection fraction (LVEF) 24 ± 5%, mean Society of Thoracic Surgeons (STS) mortality 11% (range 3–17%)). The Impella catheter traversed the aortic valve (AV) unassisted in only one patient, with four cases requiring balloon-assist techniques. All patients underwent planned revascularisation; mean procedure time 177 min (range 135–252 min), mean number of stents 3.4 (range 1–8), with three patients requiring rotational atherectomy. All procedures were well tolerated, with absence of arrhythmia, hypotension, pulmonary edema, stroke, or myocardial infarction. One patient died 48 hr post-PCI of multi-organ failure. The four remaining patients were well at 30 days. Conclusion Implantation of the 2.5 and 3.8 L Impella appears feasible in patients with severe AS and left ventricle (LV) impairment. A balloon-assist technique may be used to facilitate device implantation when initial unassisted attempts fail. Improved hemodynamic stability may enhance the tolerability of lengthy and complex procedures.

The cost-effectiveness of a new percutaneous ventricular assist device for high-risk PCI patients: mid-stage evaluation from the European perspective

Abstract Objective: A new and smaller percutaneous ventricular assist device (pVAD, Impella, Abiomed, Danvers, MA) has been developed to provide circulatory support in hemodynamically unstable patients and to prevent hemodynamic collapse during high-risk percutaneous coronary interventions (PCI). The objective of the study was to assess the cost-effectiveness of this specific device compared to the intra-aortic balloon pump (IABP) from the European perspective. Additional analysis on extracorporeal membrane oxygenation was conducted for observational purposes only, given its use in some European countries. Methods: A combination of a decision tree and Markov model was developed to assess the cost-effectiveness of the small, pVAD. The short-term (30-day) effectiveness and safety (early survival, risk of bleeding, and stroke) were modeled, as well as long-term risk of major adverse cardiovascular events (recurrent myocardial infarction, stroke, and heart failure). The short-term effectiveness and safety data for the device were obtained from two registries (the Europella and USpella), both of which are large multi-center studies in high-risk patient groups. Probabilities of long-term major adverse cardiovascular events were obtained from various published clinical studies. The economic analysis was conducted from a German statutory health insurance perspective and only direct medical costs were included. Cost-effectiveness was estimated over a 10-year time horizon. Results: Compared with IABP, the pVAD generated an incremental quality-adjusted life-year (QALY) of 0.22 (with Euro-registry data) and 0.27 (with US-registry data). The incremental cost-effectiveness ratio (ICER) of the device varied between €38,069 (with Euro-registry data) and €31,727 (with US-registry data) per QALY compared with IABP. Key limitations: Unadjusted, indirect comparisons of short-term effectiveness and safety between the interventions were used in the model. Cost and utility data were retrieved from various sources. Therefore, differences in patient populations may bias the estimated cost-effectiveness. Conclusions: Compared with IABP, the pVAD is a cost-effective intervention for high-risk PCI patients, with ICERs well-below the conventional cost-effectiveness threshold.

Symmetrical expansion of an Edwards Sapien valve in a congenitally bicuspid aortic valve

There are little data on the efficacy and safety of the Edwards Sapien valve (Edwards Lifesciences, Irvine, California, USA) in congenital, bicuspid aortic valve stenosis. Patients with bicuspid valves were excluded from the randomised PARTNER trial.1 Bicuspid valves differ from tricuspid aortic valves in that the orifice is elliptical and the leaflets are typically bulky and very heavily calcified. Bicuspid valves are considered …

A noncompliant, high pressure balloon to manage undilatable coronary lesions

Undilatable coronary lesions, due to coronary calcification, are encountered with increasing frequency. Percutaneous intervention of such lesions comes with the risk of stent underexpansion, which increases the risk of stent thrombosis and restenosis. A variety of techniques and devices are available to assist the interventionist in the treatment of calcified lesions. The OPN NC (SIS‐Medical AG, Winterthur, Switzerland) is a high‐pressure balloon (rated burst pressure 35 atm) that uses a novel, twin‐layer balloon technology to ensure uniform balloon expansion, eliminating “dog‐boning.” We report four cases of successful treatment of calcified lesions with the OPN NC balloon after dilatation with standard noncompliant balloons to high‐pressure failed.