Search

Background and Objectives: The majority of cardiac surgical procedures are performed using cardiopulmonary bypass and cardioplegia-induced cardiac arrest. Cardiac arrest and reperfusion may lead to ischemia-reperfusion injury of the myocardium. The aim of this study was to investigate whether gradual reperfusion with a slow increase in oxygen partial pressure leads to a reduction in reperfusion injury. Materials and Methods: Fifty patients undergoing elective cardiac surgery were included in this prospective randomized study. Patients in the hyperoxemic (control) group received conventional reoxygenation (paO2 250–300 mmHg). Patients in the normoxemic (study) group received gradual reoxygenation (1st-minute venous blood with paO2 30–40 mmHg, 2nd-minute arterial blood with paO2 100–150 mmHg). Periprocedural blood samples were taken serially, and markers of myocardial injury were analyzed. In addition, the influence of gradual reoxygenation on hemodynamics, inflammation, and the overall perioperative course was evaluated. Results: There was a trend toward higher CK levels in the hyperoxemia group without statistical significance; however, CK-MB and troponin T levels did not show any statistical difference between the two groups. Potassium concentrations in the coronary sinus were significantly higher in the hyperoxemia group at 3 and 8 min after opening of the aortic cross-clamp (6.88 ± 0.87 mmol/L vs. 6.30 ± 0.91 mmol/L and 5.87 ± 0.73 mmol/L vs. 5.43 ± 0.42 mmol/L, respectively; p = 0.03 and p = 0.02). All other measurements did not show a statistical difference between the two groups. Conclusions: The use of gradual reperfusion in cardiac surgery with cardiopulmonary bypass and cardiac arrest is safe. However, it does not reduce ischemia-reperfusion injury compared to standard hyperoxemic reperfusion.

Background: Minimally invasive aortic valve replacement (AVR) via upper ministernotomy (MiniAVR) is a standard alternative to full sternotomy access. Minimally invasive cardiac surgery has been proven to provide a number of benefits to patients. The aim of this study was to compare the short- and long-term outcomes after MiniAVR versus conventional AVR via full sternotomy (FS) using a biological prosthesis in an elderly higher-risk population. Methods: Between January 2006 and July 2009, 918 consecutive patients received AVR ± additional procedures with different prostheses at our center. Amongst them, 441 received isolated AVR using a biological prosthesis (median age of 74.5; range: 52–93 years; 50% females) and formed the study population (EuroSCORE II: 3.62 ± 5.5, range: 0.7–42). In total, 137 (31.1%) of the operations were carried out through FS, and 304 (68.9%) were carried out via MiniAVR. Follow-up was complete in 96% of the cases (median of 7.6 years, 6610 patient-years). Propensity score matching (PSM) resulted in two groups of 68 patients with very similar baseline profiles. The primary endpoints were long-term survival, freedom from reoperation, and endocarditis, and the secondary endpoints were early major adverse cardiac and cerebrovascular events (MACCEs). Results: FS led to shorter cardio-pulmonary bypass and aortic cross-clamp durations: 90 (47–194) vs. 100 (46–246) min (p = 0.039) and 57 (33–156) vs. 69 (32–118) min (p = 0.006), respectively. Perioperative stroke occurred in three patients (4.4%; FS) vs. one patient (1.5%; MiniAVR) (p = 0.506). The 30-day mortality was similar in both groups (2.9%, p = 1.000). Survival at 1, 5, and 10 years was 94.1 ± 3% (FS and MiniAVR), 80.3 ± 5% vs. 75.7 ± 5%, and 45.3 ± 6% vs. 43.8 ± 6%, respectively (p = 0.767). There were two (2.9%) reoperations in each group and two thrombo-embolic events (2.9%) vs. one (1.5%) thrombo-embolic event in the MiniAVR and FS groups, respectively (p = 0.596). Conclusions: In comparison to FS, MiniAVR provided similar short- and long-term outcomes in a higher-risk elderly population receiving biological prostheses. In particular, long-term survival, freedom from reoperation, and the incidence of endocarditis were comparable. These results clearly advocate for the routine use of MiniAVR as a standard procedure for AVR, even in a high-risk population.

The authors would like to make the following corrections to the published paper [...]

Objective: Minimally invasive direct coronary artery bypass grafting (MIDCAB) using the left internal thoracic artery to the left descending artery is a clinical routine in the treatment of coronary artery disease. Far less is known on right-sided MIDCAB (r-MIDCAB) using the right internal thoracic artery (RITA) to the right coronary artery (RCA). We aimed to present our experience in patients with complex coronary artery disease who underwent r-MIDCAB. Materials and Methods: Between October 2019 and January 2023, 11 patients received r-MIDCAB using RITA to RCA bypass in a minimally invasive technique via right anterior minithoracotomy without using a cardiopulmonary bypass. Underlying coronary disease was complex right coronary artery stenosis (n = 7) and anomalous right coronary artery (ARCA; n = 4). All procedure-related and outcome data were evaluated prospectively. Results: Successful minimally invasive revascularization was achieved in all patients (n = 11). There were no conversions to sternotomy and no re-explorations for bleeding. Furthermore, no myocardial infarction, no strokes, and, most importantly, no deaths were observed. During the follow-up period (median 24 months), all patients were alive and 90% were completely angina free. Two patients received a repeated revascularization after surgery but independently from the RITA-RCA bypass, which was fully competent in both patients. Conclusion: Right-sided MIDCAB can be performed safely and effectively in patients with expected technically challenging percutaneous coronary intervention of the RCA and in patients with ARCA. Mid-term results showed high freedom from angina in nearly all patients. Further studies with larger patient cohorts and more evidence are needed to provide the best revascularization strategy for patients suffering from isolated complex RCA stenosis and ARCA.

Background: Aortic valve and root replacement (AVRR) is a standardised procedure to treat patients with aortic valve and root disease. In centres with a well-established aortic valve and root repair program (valve repairs and Ross operations), only patients with very complex conditions receive AVRR; this procedure uses a mechanical or biological composite valve graft (modified Bentall–de Bono procedure). The aim of the study was to evaluate the short- and long-term results after AVRR in a high-risk population with complex pathologies. Methods: Between 2005 and 2018, a total of 273 consecutive patients (mean age 64 ± 12.8 years; 23% female) received AVRR. The indication for surgery was an acute type A aortic dissection in 18%, infective endocarditis in 36% and other pathologies in 46% patients; 39% were redo procedures. The median EuroSCORE II was 11.65% (range 1.48–95.63%). Concomitant surgery was required in 157 patients (58%). Results: The follow-up extended to 5.2 years (range 0.1–15 years) and it was complete in 96% of the patients. The 30-day mortality was 17%. The overall estimated survival at 5 and 10 years was 65% ± 3% and 49% ± 4%, respectively. Univariate and multivariate logistic regression analyses revealed the following risk factors for survival: perioperative neurological dysfunction (OR 5.45), peripheral artery disease (OR 4.4) and re-exploration for bleeding (OR 3.37). Conclusions: AVRR can be performed with acceptable short- and long-term results in a sick patient population. The Bentall–De Bono procedure may be determined to be suitable for only elderly or high-risk patients. Any other patients should receive an AV repair or the Ross procedure in well-established centres.

Background: Minimally invasive mitral valve (MV) surgery has emerged as an alternative to conventional sternotomy aiming to decrease surgical trauma. The aim of the study was to describe our experience with minimally invasive MV surgery through partial upper sternotomy (PUS) regarding short- and long-term outcomes. Methods: From January 2004 through March 2014, 419 patients with a median age of 58.9 years (interquartile range 18.7; 31.7% females) underwent isolated primary MV surgery using PUS. Myxomatous degenerative MV disease was the predominant pathology (77%). The patients’ mean EuroSCORE II risk profile was 3.9 ± 3.6%. Results: Mitral valve repair was performed in 384 patients (91.6%) and replacement in 35 patients (8.4%). Thirty-day mortality was 3.1%. In total, 29 (6.9%) deaths occurred during the follow-up. The overall estimated survival at 1, 5, and 10 years was 93.1 ± 1.3%, 87.1 ± 1.9%, and 81.1 ± 3.4%. Reoperation was necessary in 14 (3.3%) patients. The overall freedom from MV reoperation at 1, 5, and 10 years was 98.2 ± 0.7%, 96.1 ± 1.2%, and 86.7 ± 6.7% and the overall freedom from recurrent MV regurgitation > grade 2 in repaired valves at 1, 5, and 10 years was 98.8 ± 0.6%, 98.8 ± 0.6%, and 94.6 ± 3.3%. Conclusions: Minimally invasive MV surgery via PUS can be performed with particularly good early and late results. Thus, the PUS approach with the use of standard surgical instruments and cannulation techniques can be a valuable option for the MV surgery either in patients contraindicated or not suitable to minithoracotomy.

Aims: Off-pump coronary artery bypass graft surgery (OPCAB) is an established alternative to on-pump surgical revascularization. Previous studies in patients with low or intermediate risk showed no significant differences between off-pump and on-pump surgical revascularization. The aim of this study was to compare the two techniques in patients with high operative risk. Methods: PRAGUE-6 is a prospective randomized single-center study of 206 patients, with an additive EuroSCORE ≥ 6, scheduled for isolated coronary surgery: Group A - on-pump (n = 108) versus Group B - off-pump (n = 98). The primary outcome was a combined endpoint of all-cause deaths, stroke, myocardial infarction, or renal failure requiring new hemodialysis, within 30 days and 1 year after randomization. All data were analyzed using the "intention-to-treat" principle. Results: Early postoperative myocardial infarction was detected in 12.1% (A) vs. 4.1% (B) of patients (P = 0.048, hazard ratio 0.32, 95% CI 0.11-0.99). There was a significantly higher incidence of primary combined end-point in group A (20.6% vs. 9.2%, P = 0.028, HR 0.41, 95% CI 0.19-0.91) in the first 30 days, but not after 1 year (30.8% vs. 21.4%, P = 0.117, HR 0.65, CI 0.37-1.12). Conclusion: Off-pump surgical revascularization in patients with high operative risks can significantly reduce the incidence of major postoperative complications during the first 30 days. There was no statistically significant difference in the incidence of these complications after 1 year.

Impaired myocardial bioenergetics is a hallmark of many cardiac diseases. There is a need of a simple and reproducible method of assessment of mitochondrial function from small human myocardial tissue samples. In this study we adopted high-resolution respirometry to homogenates of fresh human cardiac muscle and compare it with isolated mitochondria. We used atria resected during cardiac surgery (n = 18) and atria and left ventricles from brain-dead organ donors (n = 12). The protocol we developed consisting of two-step homogenization and exposure of 2.5% homogenate in a respirometer to sequential addition of 2.5 mM malate, 15 mM glutamate, 2.5 mM ADP, 10 μM cytochrome c, 10 mM succinate, 2.5 μM oligomycin, 1.5 μM FCCP, 3.5 μM rotenone, 4 μM antimycin and 1 mM KCN or 100 mM Sodium Azide. We found a linear dependency of oxygen consumption on oxygen concentration. This technique requires < 20 mg of myocardium and the preparation of the sample takes