Images in cardiovascular medicine: Delayed right ventricular perforation by a transvenous active fixation implantable cardioverter-defibrillator lead: echocardiographic diagnosis and surgical management

Next-Generation Cardiac Interfacing Technologies Using Nanomaterial-Based Soft Bioelectronics

Cardiac interfacing devices are essential components for the management of cardiovascular diseases, particularly in terms of electrophysiological monitoring and implementation of therapies. However, conventional cardiac devices are typically composed of rigid and bulky materials and thus pose significant challenges for effective long-term interfacing with the curvilinear surface of a dynamically beating heart. In this regard, the recent development of intrinsically soft bioelectronic devices using nanocomposites, which are fabricated by blending conductive nanofillers in polymeric and elastomeric matrices, has shown great promise. The intrinsically soft bioelectronics not only endure the dynamic beating motion of the heart and maintain stable performance but also enable conformal, reliable, and large-area interfacing with the target cardiac tissue, allowing for high-quality electrophysiological mapping, feedback electrical stimulations, and even mechanical assistance. Here, we explore next-generation cardiac interfacing strategies based on soft bioelectronic devices that utilize elastic conductive nanocomposites. We first discuss the conventional cardiac devices used to manage cardiovascular diseases and explain their undesired limitations. Then, we introduce intrinsically soft polymeric materials and mechanical restraint devices utilizing soft polymeric materials. After the discussion of the fabrication and functionalization of conductive nanomaterials, the introduction of intrinsically soft bioelectronics using nanocomposites and their application to cardiac monitoring and feedback therapy follow. Finally, comments on the future prospects of soft bioelectronics for cardiac interfacing technologies are discussed.

Bow-and-arrow sign on point-of-care ultrasound for diagnosis of pacemaker lead-induced heart perforation: A case report and literature review

BACKGROUND

Pacemaker lead-induced heart perforation is a rare but life-threatening complication of pacemaker implantation, and timely diagnosis remains a challenge for clinicians. Here, we report a case of pacemaker lead-induced cardiac perforation rapidly diagnosed by a “bow-and-arrow” sign on point-of-care ultrasound (POCUS).

CASE SUMMARY

A 74-year-old Chinese woman who had undergone permanent pacemaker implantation 26 d before suddenly developed severe dyspnea, chest pain, and hypotension. The patient had received emergency laparotomy for an incarcerated groin hernia and was transferred to the intensive care unit 6 d before. Computed tomography was not available due to unstable hemodynamic status, so POCUS was performed at the bedside and revealed severe pericardial effusion and cardiac tamponade. Subsequent pericardiocentesis yielded a large volume of bloody pericardial fluid. Further POCUS by an ultrasonographist revealed a unique “bow-and-arrow” sign indicating right ventricular (RV) apex perforation by the pacemaker lead, which facilitated the rapid diagnosis of lead perforation. Given the persistent drainage of pericardial bleeding, urgent off-pump open chest surgery was performed to repair the perforation. However, the patient died of shock and multiple organ dysfunction syndrome within 24 h post-surgery. In addition, we also performed a literature review on the sonographic features of RV apex perforation by lead.

CONCLUSION

POCUS enables the early diagnosis of pacemaker lead perforation at the bedside. A step-wise ultrasonographic approach and the “bow-and-arrow” sign on POCUS are helpful for rapid diagnosis of lead perforation.

Echocardiography in patients with complications related to pacemakers and cardiac defibrillators

The evolving indications and uses for implantable cardiac devices have led to a significant increase in the number of implanted devices each year. Implantation of endocardial leads for permanent pacemakers and cardiac defibrillators can cause many delayed complications. Complications may be mechanical and related to the interaction of the device leads with the valves and endomyocardium, e.g., perforation, infection, and thrombosis, or due to the electrical pacing of the myocardium and conduction abnormalities, e.g., left ventricular dyssynchrony. Tricuspid regurgitation, another delayed complication in these patients, may be secondary to both mechanical and pacing effects of the device leads. Echocardiography plays an important role in the diagnosis of these device-related complications. Both two-dimensional transthoracic echocardiography and transesophageal echocardiography provide useful diagnostic information. Real time three-dimensional echocardiography is a novel technique that can further enhance the detection of lead-related complications.

Late perforation by cardiac implantable electronic device leads: clinical presentation, diagnostic clues, and management

Late intracardiac lead perforation is defined as migration and perforation of an implanted lead after 1 month of cardiac electronic device implantation. It is an under-recognized complication with significant morbidity and mortality, particularly if not recognized early. Two patients with late perforation caused by passive-fixation leads are reported and the clinical features of their presentation and management are reviewed. We conducted a thorough review of the available English language literature pertaining to this complication to draw relevant conclusions regarding presentation, diagnosis, and management. Early recognition of this complication is important as the indications for and numbers of patients who receive cardiac implantable electronic devices continue to expand.