Minimally Invasive Aortic Valve Surgery

*Anze Djordjevic and Igor Knez*

### **Abstract**

Minimally invasive aortic valve surgery by definition means performing procedures through alternative approaches without the need to divide the sternum completely. Even though this contributes towards lowering the mortality and morbidity of patients, minimally invasive techniques have to be tailored to the unique patient as well as surgeon characteristics. With the advancements made in invasive cardiology techniques, the line between invasive cardiology and minimally invasive cardiac surgery is becoming thinner and thinner. We are presenting state-of-the-art techniques and outcomes for surgical aortic valve replacement via upper ministernotomy or anterior right mini-thoracotomy. In addition, aortic valve repair and valve-sparing procedures through a minimally invasive approach are discussed.

**Keywords:** aortic valve, valve surgery, minimally invasive surgery, upper mini-sternotomy, right anterior mini-thoracotomy

### **1. Introduction**

Modern and complex aortic valve surgery is dependent on extracorporeal circulation established first in 1953 by Gibbon [1]. The first, Hufnagel's aortic valve was implanted in the descending aorta in 1956 [2] and from then on annual numbers of aortic valve procedures performed through a full median sternotomy have risen significantly over the next decades. In 2002, Cribier performed the first transcatheter aortic valve implantation (TAVI), which paved the way for percutaneously resolving patients with prohibitive surgical risk [3]. Although, first minimally invasive approaches were developed a decade earlier, they gained increased interest after ever looser indications for TAVI. That dictated a response from the cardiac surgery society. Cosgrove performed the first minimally invasive aortic valve replacement (AVR) through a right parasternal approach back in 1996 [4]. In the same decade, more minimally invasive approaches were developed, such as upper mini-sternotomy, anterior right mini-thoracotomy (ART) or transverse sternotomy. Today, most isolated AVRs are performed through either upper mini-sternotomy or ART (**Figure 1**) with reduced pain, improved respiratory function, early recovery and an overall reduction in trauma.

Regardless of the approach, some essentials must not be compromised in aortic valve surgery. These include safe application of a stable aortic cross-clamp, adequate visualization of the aortic valve, ensuring the same degree of myocardial protection as in median sternotomy, enabled approach to the aortic root and ascending aorta, and ability to quickly convert to median sternotomy if needed.

**Figure 1.** *Different approaches for aortic valve surgery. Left: median sternotomy; middle: upper mini-sternotomy; right: anterior right mini-thoracotomy.*

The present chapter aims to describe the two most commonly used minimally invasive approaches to aortic valve surgery (upper mini-sternotomy and ART) with a special focus on surgical technique and outcomes.
