Page 51 - Read Online

Page 6 of 15 Ashenhurst et al. Vessel Plus 2024;8:3 https://dx.doi.org/10.20517/2574-1209.2023.90

Complications such as sternal dehiscence, mediastinitis, malunion, and chronic pain can arise as a result of
sternotomy. The incidence of deep sternal wound infections has been reported between 1% and 8% and is
associated with a mortality of approximately 10%-25% [30-35] . Deep sternal wound infections greatly increase
the morbidity and mortality of patients and are a significant burden on the healthcare systems, with
potential long-term implications [34,35] .

With a smaller incision and preservation of the sternum, access to the heart by a mini-thoracotomy avoids
the risks associated with sternal trauma. Thoracotomy incisions appreciably mitigate the risk of deep sternal
wound infections and have been consistently associated with lower rates of wound infection [17,20,36] .

Chronic pain following a sternotomy incision affects approximately 17%-56% of surgical patients, having
[8]
serious implications for the patient’s recovery . A prospective study found that, in comparison, patients
undergoing MICS CABG experience lower pain levels, possibly because of preserved bony thorax integrity
permitting earlier mobilization [37,38] . However, persistent pain following minimally invasive cardiac surgery
continues to be a complication due to the nature of the incision causing damage to the ribs, pleura,
intercostal nerves, costovertebral joints, and muscles. Pain management for thoracotomy usually requires a
multimodal approach and can include nerve blocks, cryoanalgesia, liposomal bupivacaine, nonsteroidal
anti-inflammatory drugs, and gabapentinoids [38,39] .

Open heart surgery involving a sternotomy incision leaves patients with a significant scar down the midline
[Figure 4]. The scar left by a small thoracotomy, in comparison, extends 6 to 10 centimeters and is highly
discrete [Figure 5].

Early outcomes
The limited availability of comprehensive studies comparing the long-term outcomes of patients
undergoing minimally invasive coronary artery bypass grafting (MICS CABG) vs. conventional CABG has
increased the urgency to conduct rigorous research to supplement such gaps in the literature. This urgency
[17]
is primarily driven by the growing popularity of the MICS CABG procedure . The Minimally Invasive
coronary surgery compared to STernotomy coronary artery bypass grafting (MIST) trial is the first
multicenter prospective, randomized clinical trial comparing the postoperative quality of life for patients
after conventional vs. minimally invasive CABG . The results of this trial will be critical in ascertaining if
[40]
MICS CABG has a clinical benefit over sternotomy. Table 2 provides a summary of the early clinical
outcomes of contemporary, published papers evaluating MICS CABG surgeries.

In McGinn and Ruel’s inaugural paper, 450 patients with CAD underwent MICS CABG between 2005 and
[17]
2008 . The operation was completed without conversion to sternotomy in 433 (96.2%) of the 450 patients
and perioperative mortality occurred in 6 patients (1.3%). Follow-up after a mean of 19.2 ± 9.4 months was
available from the series’ first 300 patients. In this mid-term period, 10 patients (3.0%) required PCI and 2
(0.6%) mid-term saphenous vein graft failures occurred. Unlike MIDCAB, which is restricted to one LITA-
LAD graft, MICS CABG can access all regions of the heart and, as such, can treat diffuse CAD. This
inaugural paper introduced MICS CABG as a safe and reproducible procedure associated with complete
vascularization, low morbidity and mortality profile, and graft configuration comparable to conventional
CABG. From its inception, the literature has subsequently shown a growing, significant interest in MICS
CABG procedures.

In a case-matched study, Lapierre investigated the difference in patient outcomes by comparing those who
underwent MICS CABG vs. OPCAB . Patients were propensity matched using criteria including age,
[20]