Ventricular Fibrillation 7 Years After Left Ventricular Assist Device Implantation

Resuscitation of patients with durable mechanical circulatory support with acutely altered perfusion or cardiac arrest: A scoping review

BACKGROUND

There is an increasing prevalence of durable mechanical circulatory supported patients in both the in-and-out of hospital communities. The scientific literature regarding the approach to patients supported by durable mechanical circulatory devices who suffer acutely impaired perfusion has not been well explored.

METHODS

The International Liaison Committee on Resuscitation Advanced, Basic, and Pediatric Life Support Task Forces conducted a scoping review of the literature using a population, context, and concept framework.

RESULTS

A total of 32 publications that included patients who were receiving durable mechanical circulatory support and required acute resuscitation were identified. Most of the identified studies were case reports or small case series. Of these, 11 (34.4%) included patients who received chest compressions. A number of studies reported upon delays in the application of chest compressions resulting from complexity due to the expected pulselessness in some patients with continuous flow left-ventricular assist devices as well as from concern regarding potential dislodgement of the mechanical circulatory support device. Three observational studies identified worse outcomes in durable mechanical circulatory support receiving patients with cardiac arrest and acutely impaired perfusion who received chest compressions as compared to those who did not, however those studies were at high risk of bias. Of 226 patients across 11 studies and two published scientific abstracts who sustained cardiac arrest while supported by durable MCS and underwent chest compressions, there were no reported instances of device dislodgement and 71 (31.4%) patients had favorable outcomes.

CONCLUSIONS

There is a scarcity of evidence to inform the resuscitation of patients with durable mechanical circulatory support (MCS) experiencing acute impairment in perfusion and cardiac arrest. Reports indicate that delays in resuscitation often stem from rescuers' uncertainty about the safety of administering chest compressions. Notably, no instances of device dislodgement have been documented following chest compressions, suggesting that the risk of harm from timely CPR in these patients is minimal.

The role of atria in ventricular fibrillation after continuous-flow left ventricular assist device implantation in ovine model

Objectives

This study attempted to explore the hemodynamics and potential mechanisms driving pulmonary circulation in status of ventricular fibrillation (VF) following continuous-flow left ventricular assist device (CF-LVAD) implantation.

Methods

An ovine CF-LVAD model was built in small-tailed Han sheep, with the pump speed set as 2,400 rpm. VF was induced following ventricular tachycardia using a temporary pacemaker probe to stimulate the right and left ventricular free walls. The central venous pressure (CVP), pump flow (PF), pulmonary artery flow (PAF) and other major indicators were observed and recorded after VF.

Results

Low-flow systemic and pulmonary circulation could be sustained for 60 min under VF with sinus atrial rhythm after CF-LVAD implantation. The CVP gradually increased. The mean PF declined from 1.80 to 1.20 L/min, and the mean PAF decreased from 1.62 L/min to 0.87 L/min. Under VF with atrial fibrillation, the systemic and pulmonary circulation couldn't be sustained. The CVP jumped from the 5 mmHg baseline to 12 mmHg, the mean PF rapidly decreased from 3.45 L/min to 0.79 L/min, and the PAF declined from 3.94 L/min to 0.77 L/min.

Conclusion

The atrial rhythm and function might be essential for the circulation maintenance in patients with VF after CF-LVAD implantation.

A review of new-onset ventricular arrhythmia after left ventricular assist device implantation

INTRODUCTION

Heart failure (HF) is a severe and terminal stage of various heart diseases. Left ventricular assist devices (LVADs) are relatively mature and have contributed to the treatment of end-stage HF. Ventricular arrhythmia (VA) is a common complication after LVAD implantation, including ventricular tachycardia and ventricular fibrillation, both of which may cause abnormal circulation in the body.

METHODS

A literature search was conducted in the PubMed database, "Ventricular Arrhythmia" OR "VA" OR "Arrhythmia" OR "Ventricular Tachycardia," OR "Ventricular Fibrillation" AND "LVAD" OR "Left Ventricular Assist Device" OR "Heart Assist Device" as either keywords or MeSH terms, the authors screened the titles and abstracts of the articles. Eventually, 12 original research articles were retrieved.

RESULTS

The 0.83 [95%CI: 0.77, 0.89] of patients were male. A whole of 53% [95%CI:0.25, 0.81] of VA patients had a history of atrial fibrillation and 61% [95%CI:0.52, 0.69] had a history of VA. 39% [95%CI:0.29, 0.49] of the participants had no prior history of VA and experienced new VA following CF-LVAD implantation. Following CF-LVAD implantation, 59% [95%CI:0.51, 0.67] of patients developed the early VA (VA ≤ 30 days). The 30-day mortality of patients was 4% [95%CI:0.01, 0.07]. And overall mortality was 28% [95%CI:0.15, 0.41] The reported incidence of VA after LVAD implantation is not identical in different medical centers and ranges from 20% to 60%. The mechanism of VA after LVAD implantation is summarized as primary cardiomyopathy-related, device mechanical stimulation, myocardial scarring, ventricular displacement, electrolyte regulation, and other processes.

CONCLUSIONS

A preoperative VA history is considered a predictor of VA following LVAD implantation in most studies. Multiple mechanisms and factors, such as prevention of "suction events", ablation, and ICD, should be considered for the prevention and treatment of postoperative VA in patients requiring long-term VAD treatment. This study provides a reference for the clinical application of LAVD and the prevention of postoperative VA after LVAD implantation. Future multicenter prospective studies with uniform patient follow-up are needed to screen for additional potential risk factors and predictors. These studies will help to define the incidence rate of VA after LAVD implantation. As a result, we provide guidance for the selection of preventive intervention.