**6.7 Sequential bypass grafting**

• A temporary pacing wire can be placed for anastomosis to RCA to combat the

• Anastomosis is performed in a routine manner with Polypropylene 7-0 or 8-0

• The intima of both the graft and the recipient vessels must be visualized each

• Bilateral IMA grafting (typically to the left heart) has been shown to improve survival and intervention-free survival and should be performed whenever

• After completion of anastomoses, heparin could be reversed with protamine.

• Protamine is given (0.75–1.0 mg/kg) to incompletely reverse the heparin, leaving each patient with an ACT less than 150 s at the conclusion of the case.

• The avoidance of CPB should not come at the price of any compromise in

In some of the situations, CABG should be performed on CPB. These are as

**6.5 Hemodynamic instability and conversion to cardiopulmonary bypass**

a. Ischemic arrhythmias unresponsive to heparin and antiarrhythmic

b. Cardiogenic shock due to acute infarction or severe global ischemia.

the goals of hemodynamic stability and complete, precise revascularization.

• Application of compression with the coronary stabilizer—achieve and

• Less commonly, regional myocardial ischemia is a cause of hemodynamic

pectus excavatum, previous left pneumonectomy)

**6.6 Causes of hemodynamic instability**

rightward displacement of the heart).

**keeping the following points in consideration:**

c. Physical conditions that limit rightward displacement of the heart (deep

Although avoidance of CPB is generally a worthwhile goal, it does not supersede

• Imperfect technique in cardiac displacement (compressing the right atrium or right ventricle or kinking of the right ventricular outflow tract during

maintain tissue capture with a minimum of downward pressure on the heart. This will optimize both coronary stabilization and hemodynamic stability.

**The risk of myocardial ischemia during off-pump CABG can be reduced by**

sutures for LIMA grafting or venous grafting.

*The Current Perspectives on Coronary Artery Bypass Grafting*

contraindications do not exist.

anastomotic precision.

medications.

instability.

**98**

follows:

time the needle is placed through the anastomosis.

bradycardia.

The sequential bypass graft is an effective multiple-bypass technique when graft availability is limited [19] and has been reported to allow improved rates of patency in bypass procedures on narrow coronary arteries [20, 21]. Compared with regular end-to-side anastomosis, however, side-to-side anastomosis is a relatively complex procedure.

Methods of side-to-side anastomosis include the following:

1.A diamond configuration, in which the graft axis lies perpendicular to the axis of the target coronary vessel (crossed side-to-side anastomosis) (**Figure 15**)

**Figure 15.** *Crossed side-to-side anastomosis.*

◦ Urgency of operation

*DOI: http://dx.doi.org/10.5772/intechopen.88932*

◦ Severe LV dysfunction

unstable angina, and older age.

wound infection [25, 28].

**7. Results**

**101**

◦ Increased extent of coronary artery disease

*Coronary Artery Bypass Grafting: Surgical Anastomosis: Tips and Tricks*

• **Adverse neurological outcomes**—a multicenter study by Roach and

colleagues of 2108 patients undergoing CABG with CPB documented adverse cerebral outcomes in 129 patients (6.1%) [24]. Type 1 deficits (major focal deficits, stupor, and coma) occurred in 3.1%, and type 2 deficits (deterioration in intellectual function or memory) in 3.0% of the patients. Predictors of type 1 deficits included the presence of proximal aortic arteriosclerosis, history of prior neurologic disease, intra-aortic balloon pump, diabetes, hypertension,

• **Mediastinitis**—deep sternal wound infection occurs in 1–4% of patients after CABG with CPB and is associated with increased mortality [25]. Obesity is a risk factor for mediastinitis [26]. Other factors associated with an increased prevalence of deep wound infection include diabetes, previous CABG, the use of both IMAs, and duration of operation [26, 27]. Randomized trials have shown that off-pump CABG is not associated with a lower prevalence of sternal

• **Renal dysfunction**—in a multicenter study of renal dysfunction after CABG with CPB in 2222 patients, "dysfunction" was defined as a postoperative serum creatinine level of 2.0 mg dL<sup>1</sup> or greater, or an increase of 0.7 mg dL<sup>1</sup> or more from preoperative level [29]. Renal dysfunction occurred in 171 (7.7%) patients, and 30 (1.4%) required dialysis. Early mortality was 0.9% among patients who did not develop renal dysfunction, 19% in those with renal dysfunction who did not require dialysis, and 63% among those who required dialysis. Preoperative risk factors for renal dysfunction included advanced age, moderate to severe cardiac failure, previous CABG, diabetes, and preexisting renal disease [29]. In two randomized trials, prevalence of postoperative renal

• **Myocardial infarction**—perioperative MI, usually defined by the appearance of new Q waves in the ECG or non-Q wave MI can also occur which are detected by elevation of serum myocardial biomarkers, is most often related to inappropriate myocardial management, technical problems, or incomplete revascularization. Prevalence of MI is approximately 2.5–5% [31]. Perioperative infarction, when quantitatively more than trivial, is a risk factor for later death [32]. Including perioperative cases, MI is relatively uncommon after CABG, with 94% of patients in the Katholieke Universiteit, Leuven, Belgium (KU Leuven)

experience free of infarction for at least 5 years and 73% for at least 15 years [33].

• **Unsatisfactory quality of life**—even though unsatisfactory quality of life after CABG is one of the most important unfavorable outcome events, quantifying it

is very difficult because it depends on the following three factors:

failure was similar in on-pump and off-pump groups [28, 30].

◦ Left main disease

#### **Figure 16.** *Parallel side-to-side anastomosis.*

	- Continuous or interrupted sutures can be used.
	- The side-to-side anastomoses used in SB are technically difficult compared with regular end-to-side anastomoses.
	- Interrupted crossed side-to-side anastomosis greatly simplifies this procedure.

In an experimental study with animals, Shioi [22] compared various techniques for performing anastomoses, reporting that crossed side-to-side anastomosis enabled a larger opening than did parallel side-to-side anastomosis and that interrupted sutures enabled a larger anastomotic opening than did a continuous suture.
