Synchronous force and Ca2+ measurements for repeated characterization of excitation-contraction coupling in human myocardium

Dysfunctional Ca2+ signaling affects the myocardial systole and diastole, may trigger arrhythmia and cause transcriptomic and proteomic modifications in heart failure. Thus, synchronous real-time measurement of Ca2+ and force is essential to investigate the relationship between contractility and Ca2+ signaling and the alteration of excitation-contraction coupling (ECC) in human failing myocardium. Here, we present a method for synchronized acquisition of intracellular Ca2+ and contraction force in long-term cultivated slices of human failing myocardium. Synchronous time series of contraction force and intracellular Ca2+ were used to calculate force-calcium loops and to analyze the dynamic alterations of ECC in response to various pacing frequencies, post-pause potentiation, high mechanical preload and pharmacological interventions in human failing myocardium. We provide an approach to simultaneously and repeatedly investigate alterations of contractility and Ca2+ signals in long-term cultured myocardium, which will allow detecting the effects of electrophysiological or pharmacological interventions on human myocardial ECC.

A novel intrapericardial pulsatile device for individualized, biventricular circulatory support without direct blood contact

OBJECTIVE

Due to severely limited donor heart availability, durable mechanical circulatory support remains the only treatment option for many patients with end-stage heart failure. However, treatment complexity persists due to its univentricular support modality and continuous contact with blood. We investigated the function and safety of reBEAT (AdjuCor GmbH), a novel, minimal invasive mechanical circulatory support device that completely avoids blood contact and provides pulsatile, biventricular support.

METHODS

For each animal tested, an accurately sized cardiac implant was manufactured from computed tomography scan analyses. The implant consists of a cardiac sleeve with three inflatable cushions, 6 epicardial electrodes and driveline connecting to an electro-pneumatic, extracorporeal portable driver. Continuous epicardial electrocardiogram signal analysis allows for systolic and diastolic synchronization of biventricular mechanical support. In 7 pigs (weight, 50-80 kg), data were analyzed acutely (under beta-blockade, n = 5) and in a 30-day long-term survival model (n = 2). Acquisition of intracardiac pressures and aortic and pulmonary flow data were used to determine left ventricle and right ventricle stroke work and stroke volume, respectively.

RESULTS

Each implant was successfully positioned around the ventricles. Automatic algorithm electrocardiogram signal annotations resulted in precise, real-time mechanical support synchronization with each cardiac cycle. Consequently, progressive improvements in cardiac hemodynamic parameters in acute animals were achieved. Long-term survival demonstrated safe device integration, and clear and stable electrocardiogram signal detection over time.

CONCLUSIONS

The present study demonstrates biventricular cardiac support with reBEAT. Various demonstrated features are essential for realistic translation into the clinical setting, including safe implantation, anatomical fit, safe device-tissue integration, and real-time electrocardiogram synchronized mechanical support, result in effective device function and long-term safety.

Case report: Central venous catheter thrombosis complicated by chronic thromboembolic disease/pulmonary hypertension in two children requiring parenteral nutrition

Chronic thromboembolic pulmonary hypertension is a rare but life-threatening complication of long-term central venous catheters (CVC) in children. However, evidence in terms of potential treatment strategies and outcome data remains scarce. We describe two cases of CVC-related thrombosis (Hickman-catheter) complicated by recurrent pulmonary emboli. One patient experienced a complete thromboembolic obstruction of the right pulmonary artery with normal pulmonary pressures and the second patient suffered from a central thromboembolic obstruction of both pulmonary arteries associated with severe pulmonary hypertension. Both patients successfully underwent surgical thromboendarterectomy with deep hypothermic circulatory arrest.

Case report: Heart Mate III for systemic right ventricular support in a patient with hypoplastic left heart syndrome

Ventricular assist device implantation presents a possible bridge to heart transplantation for patients with failing Fontan physiology. However, evidence regarding outcome and possible pitfalls associated with the Fontan circulation is still insufficient. We describe the course of a 13-year-old male, who was born with hypoplastic left heart syndrome and underwent HeartMate III implantation due to refractory failure of the systemic right ventricle.

[Gluteal compartment syndrome after immobilization following opioid abuse]

This article reports the case of a 42-year-old male patient, who sustained a gluteal compartment syndrome after drug-induced immobilization with subsequent rhabdomyolysis and sciatic nerve palsy. Unlike compartment syndrome of the forearm or lower leg, this is a rare condition. After immediate surgical decompression and installation of negative pressure wound treatment, hemofiltration in acute renal failure could be averted using forced diuresis. The sensorimotor function of the lower extremity improved already after the first treatment and secondary wound closure was possible after 1 week. The patient was discharged 11 days after admission with complete recovery of sensorimotor and renal functions.

Impact of Preoperative Functional Status on Quality of Life after Cardiac Surgery

BACKGROUND

 With increasing importance, health-related quality of life (HRQoL) has become a crucial outcome measure of cardiac surgery. The aim of this study was to assess the dynamics of HRQoL change within 12 months after surgery and to identify predictors of deterioration in physical and mental health.

METHODS

 The cohort of this prospective study included 164 consecutive patients who underwent elective surgery. HRQoL was assessed on the basis of the Short-Form 36 questionnaire at three different times: upon admission and at 3 and 12 months after surgery. The minimal clinically important difference (MCID) was used to determine whether the surgery resulted in deterioration of HRQoL.

RESULTS

 In general, physical and mental health status improved within the first year after cardiac surgery. However, after 12 months, 7.9 and 21.2% of patients had clinically significant poorer physical (PCS) and mental component summary (MCS) scores, based on the MCID approach. The results of multivariate analysis identified preoperative health status, age < 70 years, coronary artery bypass grafting, and a previous neurological event as predictors of deterioration in postoperative HRQoL. The greatest risks for deterioration were higher preoperative PCS and MCS scores.

CONCLUSION

 Although we were able to demonstrate a general improvement in the HRQoL following cardiac surgery, in one-fifth of patients, there was no recovery of mental health status even after 1 year. As this effect is mainly determined by preoperative functional status, HRQoL should be an integral part of medical consultation, especially in younger patients with a positive perception of quality of life.