Early-Term Results of Rapid-Deployment Aortic Valve Replacement versus Standard Bioprosthesis Implantation Combined with Coronary Artery Bypass Grafting.

OBJECTIVES: Aortic stenosis is highly prevalent among patients with concomitant coronary artery disease. Surgical aortic valve replacement with coronary artery bypass grafting is usually the treatment of choice for patients with severe aortic stenosis and significant coronary disease. The aim of this study was to evaluate the outcome and hemodynamic results of the implantation of rapid-deployment valves (Rapid-Deployment Edwards Intuity Valve System [RDAVR]) versus conventional sutured valves (CSAVR) in combined surgery. METHODS: Between January 2012 and January 2017, 120 patients underwent replacement via RDAVR and 133 patients underwent replacement using CSAVR with concomitant coronary bypass grafting. Clinical and echocardiographic data were compared. RESULTS: The mean age was 76 ± 7 for RDAVR patients and 74 ± 6 years for CSAVR patients (p = 0.054); 48% in the RDAVR group were female versus 17% in the CSAVR group (p <0.002). Other characteristics such as diabetes mellitus, body-mass index, chronic obstructive pulmonary disease, nicotine consumption, and extracardiac arteriopathy were similar. Coronary three-vessel disease was more common in the RDAVR group (42.5 vs. 27.8%, p = 0.017). Both mean EuroSCORE II (6.6 ± 5.4 vs. 4.3 ± 3.0, p = 0.001) and STS score (5.4 ± 4.4 vs. 3.4 ± 2.4, p = 0.001) were significantly higher in the RDAVR group. Mean cross-clamp time (82 ± 25 vs. 100 ± 30 minutes, p < 0.001) and cardiopulmonary bypass time (119 ± 38 vs. 147 ± 53 minutes, p < 0.001) were shorter with RDAVR. The mean number of bypass grafts, length of hospital and ICU stays, and mechanical ventilation time were not statistically significant different. Hospital mortality was 2.5% for RDAVR and 9.7% for CSAVR (p = 0.019). There was a similar rate of stroke (5.8 vs. 6.0%, p = 0.990) and postoperative delirium (14.1 vs. 15.8%, p = 0.728). Mean gradients were 8.2 ± 4.1 mm Hg in the RDAVR group vs. 11.3 ± 4.6 mm Hg in the CSAVR group (p = 0.001) at discharge. CONCLUSION: RDAVR combined with coronary artery bypass grafting (CABG) can be performed extremely safely. Cross-clamp and cardiopulmonary bypass times can be significantly reduced with rapid deployment aortic valve system in the scenario of combined CABG. RDAVR resulted in lower gradients than CSAVR in patients implanted with prostheses of the same size.

Remote ischemic preconditioning in patients undergoing cardiac surgery with six ischemic cycles.

BACKGROUND: We have previously shown that remote ischemic preconditioning (RIP), which utilizes in part the extracellular RNA (eRNA)/RNase1 pathway, can induce ischemic tolerance in humans. Because RIP has thus far been tested only with four cycles of extremity ischemia/reperfusion, we investigated the influence of six cycles of ischemia on the eRNA/RNase1 pathway in cardiac patients. METHODS: Six cycles of RIP were carried out in 14 patients undergoing cardiac surgery. Blood samples were taken at 13 timepoints during surgery and at three timepoints after surgery for determining serum levels of RNase1, eRNA, and TNF-α. Trans-cardiac gradients between the myocardial blood inflow and outflow were calculated. RESULTS: Between the fourth and the sixth RIP cycles, a noticeable increase in the levels of eRNA (fourth: 151.6 (SD: 44.2) ng/ml vs sixth: 181.8 (SD: 87.5) ng/ml, p = .071), and a significant increase in RNase1 (fourth: 151.1 (SD: 42.6) U/ml vs sixth: 175.3 (SD: 41.2) U/ml, p = .001), were noted. The trans-cardiac gradients of RNase1 and eRNA before and after ischemia were not significantly different (p = .158 and p = .221; p = .397 and p = .683, respectively). Likewise, the trans-cardiac gradient of TNF-α was similar before and after ischemia. During the first 48 h after the surgery, RNase1 activity rose significantly and exceeded baseline values (135.7 (SD: 40.6) U/ml before and 279.2 (SD: 85.6) U/ml after surgery, p = .001) as did eRNA levels (148,6 (SD: 35.4) ng/ml before and 396.5 (SD: 154.5) ng/ml after surgery, p = .005), whereas TNF-α levels decreased significantly (91.7 (SD: 47.7) pg/ml before and 35.7 (SD: 36.9) pg/ml after surgery, p = .001). CONCLUSION: Six RIP cycles increased the RNase1 levels significantly above those observed with four cycles. More clinical data are required to show whether this translates into a benefit for patients.

Oral application of levosimendan before ischaemia/reperfusion with or without cardioplegic arrest in rats.

OBJECTIVES: Clinical studies have indicated minor beneficial effects of the calcium sensitizer levosimendan on clinical outcomes in patients undergoing cardiac surgery. Here, the influence of levosimendan administered 24 h before cardiac arrest on myocardial function was examined in rat hearts perfused in a Langendorff model. METHODS: Levosimendan (Levo group) or NaCl (control group) was administered to 53 rats via drinking water 24 h prior to mounting excised hearts on a Langendorff apparatus. Cardiac arrest with or without cardioplegia was induced in both groups; another set of hearts was perfused continuously. During 90-min reperfusion at 36°C, functional parameters were measured and normalized to baseline values. Troponin I was quantified in coronary sinus effluent, and the functionality of isolated cardiomyocytes was studied. RESULTS: Oral application of levosimendan showed therapeutic efficacy. Baseline values were similar in the Levo and NaCl groups except for coronary flow. After ischaemia and reperfusion, Levo hearts did not recover better than NaCl hearts {left ventricular derived pressure: 63 [standard deviation (SD): 36.2] vs 46 (SD: 41.8)% baseline; P = 0.386}, In hearts exposed to cardioplegia, functional recovery only slightly differed in the Levo and NaCl groups [left ventricular derived pressure: 69.96 (SD: 12.7) vs 51.89 (SD: 28.1)% baseline; P = 0.09]. Cell shortening of cardiomyocytes isolated from hearts exposed to ischaemia or perfusion was better in Levo groups [cell shortening: 7.65 (SD: 1.95) %; 7.8 (SD: 1.79)% vs 6.28 (SD: 1.67)%; 6.5 (SD: 1.87)%, P < 0.001]; this benefit was absent in cardioplegia-treated hearts. CONCLUSIONS: Levosimendan applied orally before ischaemia/reperfusion improves functional recovery, but this effect is only moderate when cardioplegia is included. Differences between hearts exposed to cardioplegia or to global ischaemia may indicate why levosimendan-related beneficial effects do not directly translate into better clinical outcome.