Cardiovascular Surgery

The importance of minimally invasive cardiac operations, performed off-pump, without the support of cardiopulmonary bypass (CPB), is continuously increasing. Complete revascularization of obstructed coronary arteries is needed to obtain a better long-term outcome. Insertion into the left ventricle of an effi cient microaxial pump can be useful when targeting an important coronary artery located at posterior wall of the heart in a patient with hemodynamic defi ciency. The use of such a device can enable surgeons to avoid conversion from a preplanned off-pump strategy to traditional on-pump coronary bypass surgery. The Impella Microaxial Ventricular Assist Device ® (VAD) (Abiomed, Aachen, Germany) is a miniature pump with a 7-mm catheter and a fl ow rate of approximately 2.5-5 L/min. This device can enable cardiovascular surgery to be performed without damaging the left ventricle and causing serious aortic defi ciency. Therefore, in patients with serious comorbidity, complete revascularization may be performed off pump, with the heart beating, because of the hemodynamic stability provided with the support of the microaxial intracardiac pump. If required, this pump can also support the heart during the early postoperative period. We report the fi rst assisted beating-heart coronary artery bypass graft surgery performed with the Impella Microaxial VAD in our country. The surgery was performed on 2 patients considered high risk on the basis of EUROSCORE ® testing.

Objectives: Advanced age plays a major role in surgical risk algorithms; however, the outcomes data for the very elderly are lacking. We, therefore, evaluated the outcomes after surgical aortic valve replacement (SAVR) in nonagenarians (age, >90 years) at our institution during an 11-year period.

Background and Aims: The immediate postischemic period is marked by elevated intracellular calcium levels, which can lead to irreversible myocyte injury. Del Nido cardioplegia was developed for use in the pediatric population to address the inability of immature myocardium to tolerate high levels of intracellular calcium following cardiac surgery. Our aim in this study is to determine if this solution can be used safely and effectively in an adult, reoperative population. Methods: All patients undergoing isolated reoperative aortic valve replacement at our institution from 2010 to 2012 were retrospectively reviewed. Demographics, comorbidities, operative variables, postoperative complications, and patient outcomes were collected. Patients were divided into two groups based on cardioplegia strategy used: whole blood cardioplegia (WB, n = 61) and del Nido cardioplegia (DN, n = 52). Results: Mean age in the study was 73.4 W 14.3 years and 86 patients were male (76.1%). Eighty-four patients had undergone prior coronary artery bypass graft (CABG) (74.3%). Patients in the DN group required significantly lower total volume of cardioplegia (1147.6 W 447.2 mL DN vs. 1985.4 W 691.1 mL WB, p < 0.001) and retrograde cardioplegia dose (279.3 W 445.1 mL DN vs. 1341.2 W 690.8 mL WB, p < 0.001). There were no differences in cross-clamp time, bypass time, postoperative complication rate, or patient outcomes between groups. Conclusions: Del Nido cardioplegia use in an adult, reoperative aortic valve population offers equivalent postoperative outcomes when compared with whole blood cardioplegia. In addition, use of del Nido solution requires lower total and retrograde cardioplegia volumes in order to achieve adequate myocardial protection.

Myostatin (MSTN) is a negative regulator of muscle growth that is increased following cardiomyocyte stress and has been proposed to play a role in cardiac remodeling. We hypothesized that inhibition of MSTN would improve cardiac function and reduce skeletal muscle wasting in experimental heart failure (HF). C57BL/6J mice (n=40) were subjected to left anterior descending coronary artery ligation (HF) or no ligation (SHAM). Three weeks after surgery, HF was confirmed by echocardiography (echo). HF and SHAM animals were randomly divided into two groups receiving either drug (weekly intraperitoneal 12µg/kg dose Myo-Fc)) or vehicle, for 8 weeks. After treatment, echo was repeated, endurance running test (ERT) was performed, and mice were sacrificed. MSTN, IGF-1, Akt, P-Akt, p38, P-p38, SMAP2/3 and P-SMAD2/3 levels in heart were measured by western blot. Myo-Fc treated HF mice displayed an improvement in cardiac function as seen by echo and ERT (p<0.05). HF mice had significantly heavier hearts and decreased skeletal muscle mass, which was reversed by MSTN inhibition. MSTN inhibition decreased IGF-1 in HF mice, and prevented HFinduced upregulation of cardiac MSTN, SMAD 2/3 and P-p38, as well as P-Akt downregulation.