Cardioplexol, a new cardioplegic solution for elective CABG

Myocardial Recovery, Metabolism, and Structure after Cardiac Arrest with Cardioplexol

OBJECTIVES

 Clinical studies indicate encouraging cardioprotective potential for Cardioplexol. Its cardioprotective capacities during 45 minutes of ischemia compared with pure no-flow ischemia or during 90 minutes of ischemia compared with Calafiore cardioplegia were investigated experimentally.

METHODS

 Forty-four rat hearts were isolated and inserted into a blood-perfused pressure-controlled Langendorff apparatus. In a first step, cardiac arrest was induced by Cardioplexol or pure no-flow ischemia lasting 45 minutes. In a second step, cardiac arrest was induced by Cardioplexol or Calafiore cardioplegia lasting 90 minutes. For both experimental steps, cardiac function, metabolic parameters, and troponin I levels were evaluated during 90 minutes of reperfusion. At the end of reperfusion, hearts were fixed, and ultrastructural integrity was examined by electron microscopy.

RESULTS

 Step 1: after 90 minutes of reperfusion, hearts exposed to Cardioplexol had significantly higher left ventricular developed pressure (CP-45': 74%BL vs. no-flow-45': 45%BL; p = 0.046) and significantly better maximal left ventricular relaxation (CP-45': 84%BL vs. no-flow-45': 51%BL; p = 0.012). Oxygen consumption, lactate production, and troponin levels were similar in both groups. Step 2: left ventricular developed pressure was lower (22 vs. 48% of BL; p = 0.001) and coronary flow was lower (24 vs. 53% of BL; p = 0.002) when Cardioplexol was used compared with Calafiore cardioplegia. Troponin I levels were significantly higher under Cardioplexol (358.9 vs. 106.1 ng/mL; p = 0.016).

CONCLUSION

 Cardioplexol significantly improves functional recovery after 45 minutes of ischemia compared with pure ischemia. However, Cardioplexol protects the myocardium from ischemia/reperfusion-related damage after 90 minutes of ischemia worse than Calafiore cardioplegia.

Four decades of experience of prosthetic valve endocarditis reflect a high variety of diverse pathogens

Prosthetic valve endocarditis (PVE) remains a serious condition with a high mortality rate. Precise identification of the PVE-associated pathogen/s and their virulence is essential for successful therapy, and patient survival. The commonly described PVE-associated pathogens are staphylococci, streptococci and enterococci, with Staphylococcus aureus being the most frequently diagnosed species. Furthermore, multi-drug resistance pathogens are increasing in prevalence, and continue to pose new challenges mandating a personalized approach. Blood cultures in combination with echocardiography are the most common methods to diagnose PVE, often being the only indication, it exists. In many cases, the diagnostic strategy recommended in the clinical guidelines does not identify the precise microbial agent and to frequently, false negative blood cultures are reported. Despite the fact that blood culture findings are not always a good indicator of the actual PVE agent in the valve tissue, only a minority of re-operated prostheses are subjected to microbiological diagnostic evaluation. In this review, we focus on the diversity and the complete spectrum of PVE-associated bacterial, fungal and viral pathogens in blood, and prosthetic heart valve, their possible virulence potential, and their challenges in making a microbial diagnosis. We are curious to understand if the unacceptable high mortality of PVE is associated with the high number of negative microbial findings in connection with a possible PVE. Herein, we discuss the possibilities and limits of the diagnostic methods conventionally used and make recommendations for enhanced pathogen identification. We also show possible virulence factors of the most common PVE-associated pathogens and their clinical effects. Based on blood culture, molecular biological diagnostics, and specific valve examination, better derivations for the antibiotic therapy as well as possible preventive intervention can be established in the future.

Clinical implementation of a novel myocardial protection pathway in coronary artery bypass surgery with minimal extracorporeal circulation

INTRODUCTION

The aim of this study was to report the clinical implementation of the joint use of the Myocardial Protection System (MPS^®) and the minimal extracorporeal circulation system (MiECC), in conjunction with an institutionally refined dose/volume-dependent microplegia in coronary artery bypass grafting (CABG).

METHODS

Patients with isolated CABG surgery were included. The final protocol to achieve cardioplegic arrest consisted of warm blood cardioplegia with 20 mmol potassium (K), 1.6 g magnesium (Mg) and 40 mg lidocaine per liter (L) blood. We prospectively collected intra- and postoperative data to monitor and validate this novel approach.

RESULTS

Eighty patients were operated accordingly. Mean (SD) aortic clamping time and extracorporeal perfusion time were 67.5 (22.6) and 101.1 (31.9) minutes, respectively. Failure to induce cardiac arrest was seen in six patients at the early stage of refinement of the formula. Median (IQR) high -sensitivity cardiac troponin T (hs-cTnT) on the first postoperative day (POD) and peak hs-cTnT were 262.5 ng/L (194.3-405.8) and 265.5 ng/L (194.3-405.8), respectively. Median (IQR) creatine kinase-myocardial type (CK-MB) on POD 1 and peak CK-MB were 14.2 µg/L (10.5-22.7) and 14.2 µg/L (10.7-23.2), respectively. Median (IQR) creatine kinase (CK) on POD 1 and peak CK were 517.5 U/L (389.3-849.8) and 597.5 U/L (455.0-943.0), respectively. No patient died during hospitalization.

CONCLUSIONS

The combination of this cardioplegic formula with MPS^® and MiECC in CABG was safe and feasible. With the final chemical makeup, cardiac arrest was reliably achieved. Remarkably low postoperative cardiac markers indicate shielded cardiac protection during surgery.