Upscaling cardiac assist devices in decompensated heart failure: Choice of device and its timing

Review of Pathophysiology of Cardiogenic Shock and Escalation of Mechanical Circulatory Support Devices

PURPOSE OF REVIEW

Cardiogenic shock (CS) is a complex clinical entity that continues to carry a high risk of mortality. The landscape of CS management has changed with the advent of several temporary mechanical circulatory support (MCS) devices designed to provide hemodynamic support. It remains challenging to understand the role of different temporary MCS devices in patients with CS, as many of these patients are critically ill, requiring complex care with multiple MCS device options. Each temporary MCS device can provide different types and levels of hemodynamic support. It is important to understand the risk/benefit profile of each one of them for appropriate device selection in patients with CS.

RECENT FINDINGS

MCS may be beneficial in CS patients through augmentation of cardiac output with subsequent improvement of systemic perfusion. Selecting the optimal MCS device depends on several variables including the underlying etiology of CS, clinical strategy of MCS use (bridge to recovery, bridge to transplant or durable MCS, or abridge to decision), amount of hemodynamic support needed, associated respiratory failure, and institutional preference. Furthermore, it is even more challenging to determine the appropriate time to escalate from one MCS device to another or combine different MCS devices. In this review, we discuss the current available data published in the literature on the management of CS and propose a standardized approach for escalation of MCS devices in patients with CS. Shock teams can play an important role to help in hemodynamic-guided management and algorithm-based step-by-step approach in early initiation and escalation of temporary MCS devices at different stages of CS. It is important to define the etiology of CS, and stage of shock and recognize univentricular vs biventricular shock for appropriate device selection and escalation of therapy.

Comparison of a pulsatile and a continuous flow left ventricular assist device in high-risk PCI

BACKGROUND

Mechanical circulatory support devices are able to generate additional cardiac output or maintain sufficient circulation during high-risk PCI. We prospectively compared the hemodynamic and clinical performance of the new iVAC2L® device with the Impella 2.5® device during high-risk PCI.

MATERIALS AND METHODS

In 40 patients [10 female, age 75 ± 8 years, left ventricular ejection fraction (LVEF) 44 ± 11%] high-risk PCIs were performed under iVAC (n = 20) or Impella (n = 20) support. Hemodynamic parameters were collected before and after device placement as well as immediately after PCI. Blood parameters of hemolysis were analyzed before and after support.

RESULTS

Correct device placement was achieved in 17 patients (85%) under iVAC use and in 19 patients (95%) under Impella use. PCI success was 98%. Under iVAC2L® support, systolic, diastolic and mean aortic blood pressure increased significantly with increasing support time. In contrast, aortic pressure increased directly under Impella support, but the increase was comparable between both devices. Impella support generated a significantly higher additional blood flow, as compared to iVAC support (2.07 ± 0.09 l/min vs. 1.25 ± 0.05 l/min, p < 0.001). Five patients (iVAC n = 3) suffered from critical events during high-risk PCI, but both devices were able to maintain stable hemodynamic conditions. After PCI, one severe bleeding occurred in each group. After Impella support, haptoglobin was significantly decreased, indicating potential hemolysis.

CONCLUSIONS

High-risk PCIs under support by both devices are feasible and safe and ensure stable hemodynamic conditions also if complications occur. Aortic pressure increases significantly with both devices, but later under iVAC use. Potential hemolysis occurs more frequent under Impella support.

The effect of nurse-led interventions on re-admission and mortality for congestive heart failure: A meta-analysis

BACKGROUND

The European Society of Cardiology guidelines recommend the implementation of nurse-led heart failure programs to achieve optimal management of patients with congestive heart failure (CHF). In this analysis, we aimed to systematically show the impact of nurse-led interventions (NLI) on re-admission and mortality in patients with CHF (reduced ejection fraction).

METHODS

Publications reporting the impact of NLI on readmission and mortality in patients with CHF were carefully searched from electronic databases. Rehospitalization and mortality were the endpoints. For this analysis, the latest version of the RevMan software was used. Risk ratios (RR) with 95% confidence intervals (CI) were used to represent data following analysis.

RESULTS

A total number of 3282 participants with CHF were included in this analysis. A total of 1571 patients were assigned to the nurse-led intervention group whereas 1711 patients were assigned to the usual care group. The patients had a mean age ranging from 50.8 to 80.3 years. Male patients varied from 27.3% to 73.8%. Comorbidities including hypertension (24.6%-80.0%) and diabetes mellitus (16.7%-59.7%) were also reported. Patients had a mean left ventricular ejection fraction varying from 29.0% to 61.0%. Results of this current analysis showed that rehospitalization (RR: 0.81, 95% CI: 0.74-0.88; P = .00001) and mortality (RR: 0.69, 95% CI: 0.56-0.86; P = .0009) were significantly lower among CHF patients who were assigned to the nurse-led intervention. Whether during a shorter (3-6 months) or a longer (1-2 years) follow up time period, rehospitalization for shorter [(RR: 0.73, 95% CI: 0.65-0.82; P = .00001) vs for longer (RR: 0.81, 95% CI: 0.72-0.91; P = .0003) respectively] and mortality for shorter [(RR: 0.55, 95% CI: 0.38-0.80; P = .002) vs longer follow up time period (RR: 0.76, 95% CI: 0.58-0.99; P = .04) respectively] were significantly lower and in favor of the nurse-led interventional compared to the normal care group.

CONCLUSIONS

This systematic review and meta-analysis of randomized controlled trials showed that NLI had significant impacts in reducing the risk of rehospitalization and mortality in these patients with CHF (reduced ejection fraction). Hence, we believe that nurse-led clinics and other interventional programs would be beneficial to patients with heart failure and this practice should, in the future be implemented to the health care system.

BVS, RDN, IABP: The Afghanistan of interventional cardiology trials

In the field of medicine and cardiology newer therapy and devices have been launched with a huge promise and a lot of hype. Unfortunately, over the course of time, a good many of them like biovascular scaffold, renal denervation and intra-aortic balloon pump have failed to live up to their initial promise so much so that some of them have been withdrawn. The reason for this downfall may be multifold from incomplete understanding of the patho-physiology of disease, incomplete understanding of mechanism of action of the therapy, in-appropriate application in clinical practice, in-efficient therapy development related to flawed trial design, regulatory impediments placed on the trials or deficits in application of scientific techniques. Here-in we investigate the specific reason for failure for some of these therapies and attempt to suggest a way forward.