INTRODUCTION

Since the first report of a percutaneous method to access dry epicardial space,¹ the epicardial approach has become the cornerstone technique of catheter ablation for complex epicardial ventricular tachycardias (VT). However, significant acute complications are close to 7%,² and most of them are associated with the epicardial puncture. As an introducer needle is advanced into epicardial space under fluoroscopic guidance, it is necessary to know how to use various fluoroscopic views for determination of an appropriate puncture route. We will discuss in this chapter the rationale to use different fluoroscopic approaches for epicardial access.

FLUOROSCOPIC ASSESSMENT AND COMPLICATIONS

The epicardial access route is close to vulnerable and important structures to be avoided. Fluoroscopic guidance of the needle route is critical to avoid puncturing adjacent organs, and these landmarks should be known by VT operators. The layers traversed by the needle include the skin, superficial fascia, anterior rectus sheath/linea alba, rectus abdominis muscle, and posterior rectus sheath. The needle then travels over the dome of the diaphragm, before reaching the fibrous and parietal serous layers of the pericardium.^3,4

Since the subxiphoid percutaneous access point lies below the diaphragm, an overly steep angle at the initial course has a risk of a puncture of the diaphragm. Although puncturing the diaphragm is not a significant risk, it exposes to a risk of injury to the peritoneal organs, such as the left lobe of the liver, the stomach, transverse colon, and vessels. On the other hand, an overly shallow angle may not get beneath the sternum, resulting in intense pain from the periosteum and a failed approach. Moreover, as the internal mammary arteries lie at the margins of the sternum, a superficial puncture may damage an artery, especially when the needle entry and direction is too lateral (Figure 6.1). Therefore, it is essential to determine the degree of subxiphoid puncture regarding the fluoroscopic image.

The puncture of the heart is the most critical cause of concern during epicardial access. Inadvertent right ventricular puncture occurs in approximately 5% of cases with attempted epicardial access.^4,5 The puncture with the needle only is not associated with a severe consequence in the majority of cases; however, it is of outmost importance to recognize the right ventricular puncture has happened before advancing the sheath. Therefore, contrast should be injected to confirm layering within the epicardial space immediately after the puncture. Moreover, the guidewire should be gently advanced and must be confirmed to wrap around the left and right cardiac silhouette to exclude the possibility of an intracardiac placement of the needle tip.

The other heart-related complication during the epicardial access is coronary artery damage. The right ventricular marginal artery is situated at the acute margin of the right ventricle, where the pericardium reflects on becoming the diaphragmatic pericardium (Figure 6.1). The right ventricular marginal artery may be at risk during epicardial access in cases of arrhythmogenic right ventricular cardiomyopathy or where the right ventricle is abnormally dilated.² Moreover, it is usually preferred to approach with an angle that is more tangential to the inferior heart border to avoid the right ventricular puncture during the posterior approach; however, a puncture with overly septal direction increases the risk of the posterior descending artery injury. A coronary angiography performed prior to the epicardial access may be considered to reduce the risk for coronary artery damage.

Stay updated, free articles. Join our Telegram channel

Join