**5. Study limitations**

The success of reconstructive surgeries in patients with ICMP depends not so much on functional morphology of cardiomyocytes and the condition of myocardial trophy as on cellular-stromal interactions in cardiac muscular tissue with the background of chronic ischemia. In our opinion, identification of myocarditis etiology with the purpose of its etiotropic treatment is one of the key factors of prevention of heart failure progression in the late postoperative period in patients with ICMP. By far the correlation of the presence of myocardial inflammatory infiltration with activation of metalloproteinase system has not been fully understood. Probably, quantitative and, what is also important, qualitative content of myocardial stroma (collagen types, fibronectin, laminin, etc) determines "tolerance" of the tissue to progressive dilatation.

### **6. References**

Acorn cardiovascular, inc.™ Selected abstracts. 2000.


Avtandilov, G. 1990. *Medical morphometry,* Medicine, Moscow

based on pre- and/or intraoperative LV biopsies taken for the detection of irreversible pathological changes in myocardium by a number of qualitative and quantitative histomorphometrical values taking into account the condition of tissue trophy to the full extent, should contribute into prevention of repeated heart remodeling and progression of

Cellular-stromal relationships on the background of chronic ischemia of myocardium precondition destructive processes of a heart muscular tissue remodeling which is reflected also in peripheral blood of ICMP patients: the content of MMPs and MMP-3 and MMP-9 in particular, which becomes molecular prognostic markers of the late postoperative period. Basing on the obtained data we offer the following algorithm of surgical treatment of patients with ICMP: for the candidates for a complex surgical treatment older than 55 years old with preoperative LV ESVI >80 ml/m2 it would be reasonable to widen indications for endomyocadial biopsy at the preoperative stage or to perform intraoperative biopsy of LV myocardium in order to identify prognostic criteria of the postoperative progressive heart remodeling and take blood samples for the detection of blood markers of HF progression. If the combination of unfavorable prognostic criteria takes place: the presence of diffuse inflammatory infiltration of myocardial stroma in combination with pronounced fibrosis, low TI (<0.010) and high values of KI (>1.5) and PcDZ (>1000 mcm) of LV myocardium as well as high concentrations of MMP-3 (>7.7 ng/ml) and MMP-9 (>102.4 ng/ml) in blood serum, the patient should be refused from a standard procedure of surgical reconstruction of normal left ventricular geometry in favor of alternative methods of surgical treatment (in the case of taking preoperative biopsy of myocardium) or surgeons should refuse from SVR in favor of a surgical procedure with less risk (in case of taking intraoperative biopsy of myocardium).

The success of reconstructive surgeries in patients with ICMP depends not so much on functional morphology of cardiomyocytes and the condition of myocardial trophy as on cellular-stromal interactions in cardiac muscular tissue with the background of chronic ischemia. In our opinion, identification of myocarditis etiology with the purpose of its etiotropic treatment is one of the key factors of prevention of heart failure progression in the late postoperative period in patients with ICMP. By far the correlation of the presence of myocardial inflammatory infiltration with activation of metalloproteinase system has not been fully understood. Probably, quantitative and, what is also important, qualitative content of myocardial stroma (collagen types, fibronectin, laminin, etc) determines

Anderson, R.A. 2005. The anatomical arrangement of the myocardial cells making up the ventricular mass. *Eur. J. Cardio-thorac. Surg*, Vol. 28, 2005, pp. 517–525 Athanasuleas, C.L. 2004. Surgical ventricular restoration in the treatment of congestive heart

failure due to postinfarction ventricular dilation. *J. Am Coll. Cardiol*, Vol. 44, 2004,

chronic HF in the late postoperative period.

**5. Study limitations** 

**6. References** 

pp. 1439–1445

"tolerance" of the tissue to progressive dilatation.

Acorn cardiovascular, inc.™ Selected abstracts. 2000.

Avtandilov, G. 1990. *Medical morphometry,* Medicine, Moscow


**7** 

 *Italy* 

**Miniaturized Extracorporeal Circulation** 

*Cardiac Surgery Clinic, University of Milano-Bicocca, San Gerardo Hospital, Monza,* 

Since the first cardiac surgical operations in the early '50s, the early and long-term outcomes have been dramatically improved also because of the refinement of technology regarding the extracorporeal circulation (ECC). It is recognized the ECC is associated with a systemic inflammatory response (SIRS), which is implicated in myocardial, renal, pulmonary and neurologic dysfunction. However, although the effects of ECC are very often subclinical, in some situations they can be responsible of worse outcome in the early post-operative period. In the early 1990s, many surgeons started to perform coronary revascularization without the use of ECC with the aim of strongly reducing the subclinical and clinical effects of the SIRS. Over the past fifteen years, the "off-pump" coronary artery bypass grafting (OPCABG) has demonstrated to have good results by reducing postoperative morbidity and mortality. On the other hand, the OPCABG presents some drawbacks such as the significant learning curve of the surgeon, the high rate of incomplete revascularization in dilated and hypokinetic heart due to very difficult exposure of obtuse coronary marginal branches and

Over the past 10 years, concepts of miniaturized extracorporeal circulation (MECC) were developed with the aim of reducing the side effects of the standard ECC, strengthening the advantages of ECC and eliminate the limitations of OPCABG. In other words, the MECC

Different types of MECC circuits are on the market and although they can have some differences among them in terms of characteristics of blood pump, oxygenator membrane, length of tubing, arterial and venous filters, the principle key is substantially equal for each

The MECC circuit consists of a closed loop, which includes the oxygenator and the pump. The circuit has not any open venous reservoir. All components of MECC circuit are pretreated with heparin according to different techniques available on the market. The heparin pre-treatment of the circuit minimizes the systemic heparinization dose requirements (usually half dose of conventional ECC: 150IU/Kg instead of 300IU/Kg) (Curtis et al. 2010; Formica et al. 2009, Puheler et al. 2009; Beghi et. 2006) and provides biocompatibility for blood cells (Koivisto et al. 2010; Remadi et al. 2007; Remadi et al.

**2. Anatomy of the miniaturized extracorporeal circulation system** 

**1. Introduction** 

the lesser quality of the coronary anastomosis.

2004; Fromes et al 2002;)

joins the best of ECC with the best of "off-pump" surgery.

system: closed circuit without a venous cardiotomy reservoir.

Francesco Formica and Giovanni Paolini

