Tachyarrhythmia after the total cavopulmonary connection: incidence, prognosis, and risk factors

OBJECTIVE

The purpose of this study is to evaluate the incidence and outcomes regarding tachyarrhythmia in patients after total cavopulmonary connection.

METHODS

A retrospective analysis of 620 patients who underwent total cavopulmonary connection between 1994 and 2021 at our institution was performed. Incidence of tachyarrhythmia was depicted, and results after onset of tachyarrhythmia were evaluated. Factors associated with the onset of tachyarrhythmia were identified.

RESULTS

A total of 52 (8%) patients presented with tachyarrhythmia that required medical therapy. Onset during hospital stay was observed in 27 patients, and onset after hospital discharge was observed in 32 patients. Freedom from late tachyarrhythmia following total cavopulmonary connection at 5, 10, and 15 years was 97, 95, and 91%, respectively. The most prevalent late tachyarrhythmia was atrial flutter (50%), followed by supraventricular tachycardia (25%) and ventricular tachycardia (25%). Direct current cardioversion was required in 12 patients, and 7 patients underwent electrophysiological study. Freedom from Fontan circulatory failure after onset of tachyarrhythmia at 10 and 15 years was 78% and 49%, respectively. Freedom from occurrence of decreased ventricular systolic function after the onset of tachyarrhythmia at 5 years was 85%. Independent factors associated with late tachyarrhythmia were dominant right ventricle (hazard ratio, 2.52, p = 0.02) and weight at total cavopulmonary connection (hazard ratio, 1.03 per kilogram; p = 0.04). Type of total cavopulmonary connection at total cavopulmonary connection was not identified as risk.

CONCLUSIONS

In our large cohort of 620 patients following total cavopulmonary connection, the incidence of late tachyarrhythmia was low. Patients with dominant right ventricle and late total cavopulmonary connection were at increased risk for late tachyarrhythmia following total cavopulmonary connection.

Impact of calorie intake and weight gain after Norwood procedure on the outcome of stage II palliation

BACKGROUND

This study aimed to assess the impact of caloric intake and weight-for-age-Z-score after the Norwood procedure on the outcome of bidirectional cavopulmonary shunt.

METHODS

A total of 153 neonates who underwent the Norwood procedure between 2012 and 2020 were surveyed. Postoperative daily caloric intake and weight-for-age-Z-score up to five months were calculated, and their impact on outcome after bidirectional cavopulmonary shunt was analysed.

RESULTS

Median age and weight at the Norwood procedure were 9 days and 3.2 kg, respectively. Modified Blalock-Taussig shunt was used in 95 patients and right ventricle to pulmonary artery conduit in 58. Postoperatively, total caloric intake gradually increased, whereas weight-for-age-Z-score constantly decreased. Early and inter-stage mortality before stage II correlated with low caloric intake. Older age (p = 0.023) at Norwood, lower weight (p < 0.001) at Norwood, and longer intubation (p = 0.004) were correlated with low weight-for-age-Z-score (< -3.0) at 2 months of age. Patients with weight-for-age-Z-score < -3.0 at 2 months of age had lower survival after stage II compared to those with weight-for-age-Z-score of -3.0 or more (85.3 versus 92.9% at 3 years after stage II, p = 0.017). There was no difference between inter-stage weight gain and survival after bidirectional cavopulmonary shunt between the shunt types.

CONCLUSION

Weight-for-age-Z-score decreased continuously throughout the first 5 months after the Norwood procedure. Age and weight at Norwood and intubation time were associated with weight gain. Inter-stage low weight gain (Z-score < -3) was a risk for survival after stage II.

Dielectric elastomer actuator-based valveless pump as Fontan failure assist device: introduction and preliminary study

OBJECTIVES

Fontan failure refers to a condition in which the Fontan circulation, a surgical procedure used to treat certain congenital heart defects, becomes insufficient, leading to compromised cardiac function and potential complications. This in vitro study therefore investigates the feasibility of bladeless impedance-driven cavopulmonary assist device via dielectric elastomer actuator (DEA) as a means to address Fontan failure.

METHODS

A cavopulmonary assist device, constructed using DEA technologies and employing the impedance pump concept, is subjected to in vitro testing within a closed-loop setup. This study aims to assess the device's functionality and performance under controlled conditions, providing valuable insights into its potential application as a cavopulmonary assistive technology.

RESULTS

The DEA-based pump, measuring 50 mm in length and 30 mm in diameter, is capable of achieving substantial flow rates within a closed-loop setup, reaching up to 1.20 l/min at an activation frequency of 4 Hz. It also provides a broad range of working internal pressures (<10 to >20 mmHg). Lastly, the properties of the flow (direction, magnitude, etc.) can be controlled by adjusting the input signal parameters (frequency, amplitude, etc.).

CONCLUSIONS

In summary, the results suggest that the valveless impedance-driven pump utilizing DEA technology is promising in the context of cavopulmonary assist devices. Further research and development in this area may lead to innovative and potentially more effective solutions for assisting the right heart, ultimately benefiting patients with heart-related health issues overall, with a particular focus on those experiencing Fontan failure.

Novel para-aortic cardiac assistance using a pre-stretched dielectric elastomer actuator

OBJECTIVES

We propose an evolution of a dielectric elastomer actuator-based cardiac assist device that acts as a counterpulsation system. We introduce a new pre-stretched actuator and implant the device in a graft bypass between the ascending and descending aorta to redirect all blood through the device (ascending aorta clamped). The objective was to evaluate the influence of these changes on the assistance provided to the heart.

METHODS

The novel para-aortic device and the new implantation technique were tested in vivo in 5 pigs. We monitored the pressure and flow in the aorta as well as the pressure-volume characteristics of the left ventricle. Different activation timings were tested to identify the optimal device actuation.

RESULTS

The proposed device helps reducing the end-diastolic pressure in the aorta by up to 13 ± 4.0% as well as the peak systolic pressure by up to 16 ± 3.6%. The early diastolic pressure was also increased up to 10 ± 3.5%. With different activation, we also showed that the device could increase or decrease the stroke volume.

CONCLUSIONS

The new setup and the novel para-aortic device presented here helped improve cardiac assistance compared to previous studies. Moreover, we revealed a new way to assist the heart by actuating the device at different starting time to modify the left ventricular stroke volume and stroke work.

Longitudinal analysis of systemic ventricular function and atrioventricular valve function after the Norwood procedure

OBJECTIVES

To evaluate longitudinal systemic ventricular function and atrioventricular valve regurgitation in patients after the neonatal Norwood procedure.

METHODS

Serial postoperative echocardiographic images before Fontan completion were assessed in neonates who underwent the Norwood procedure between 2001 and 2020. Ventricular function and atrioventricular valve regurgitation were compared between patients with modified Blalock-Taussig shunt and right ventricle to pulmonary artery conduit.

RESULTS

A total of 335 patients were identified including 273 hypoplastic left heart syndrome and 62 of its variants. Median age at Norwood was 8 (7-12) days. Modified Blalock-Taussig shunt was performed in 171 patients and the right ventricle to pulmonary artery conduit in 164 patients. Longitudinal ventricular function and atrioventricular valve regurgitation were evaluated using a total of 4352 echocardiograms. After the Norwood procedure, ventricular function was initially worse (1-30 days) but thereafter better (30 days to stage II) in the right ventricle to pulmonary artery conduit group (P < 0.001). After stage II, the ventricular function was inferior in the right ventricle to the pulmonary artery conduit group (P < 0.001). Atrioventricular valve regurgitation between the Norwood procedure and stage II was more frequent in the modified Blalock-Taussig shunt group (P < 0.001). After stage II, there was no significant difference in atrioventricular valve regurgitation between the groups (P = 0.171).

CONCLUSIONS

The effect of shunt type on haemodynamics after the Norwood procedure seems to vary according to the stage of palliation. After the Norwood, the modified Blalock-Taussig shunt is associated with poorer ventricular function and worse atrioventricular valve regurgitation compared to right ventricle to pulmonary artery conduit. Whereas, after stage II, modified Blalock-Taussig shunt is associated with better ventricular function and comparable atrioventricular valve regurgitation, compared to the right ventricle to pulmonary artery conduit.

Comparison of ductus stent versus surgical systemic-to-pulmonary shunt as initial palliation in patients with univentricular heart

OBJECTIVES

In this study, we aimed to compare infants with univentricular hearts who underwent an initial ductus stenting to those receiving a surgical systemic-to-pulmonary shunt (SPS).

METHODS

All infants with univentricular heart and ductal-dependent pulmonary blood flow who underwent initial palliation with either a ductus stenting or a surgical SPS between 2009 and 2022 were reviewed. Outcomes were compared after ductus stenting or SPS including survival, probability of re-interventions and the probability to reach stage II palliations.

RESULTS

A total of 130 patients were evaluated, including 49 ductus stenting and 81 SPSs. The most frequent primary diagnosis was tricuspid atresia in 27, followed by pulmonary atresia with intact ventricular septum in 19 patients. There was comparable hospital mortality (2.0% stent vs 3.7% surgery, P = 0.91) between the groups, but shorter intensive care unit stay (median 1 vs 7 days, P < 0.01) and shorter hospital stay (median 7 vs 17 days, P < 0.01) were observed in patients with initial ductus stenting, compared to those with SPS. However, acute procedure-related complications were more frequently observed in patients with ductus stenting, compared with those with SPS (20.4 vs 6.2%, P = 0.01), and 10 patients needed a shunt procedure after the initial ductus stent. The cumulative incidence of reaching stage II was similar between ductus stenting and SPS (88.0 vs 90.6% at 12 months, P = 0.735). Pulmonary artery (PA) index (median 194 vs 219 mm2/m2, P = 0.93) at stage II was similar between patients with ductus stenting and SPS. However, the ratio of the left to the right PA index [0.69 (0.45-0.95) vs 0.86 (0.51-0.84), P = 0.015] was higher in patients who reached stage II with surgical shunt physiology, compared with patients with ductus stent physiology.

CONCLUSIONS

After initial ductus stenting in infants with univentricular heart, survival is comparable and post-procedural recovery shorter, but more acute stent dysfunctions and lower development of left PA are observed, compared to acute shunt dysfunctions. The less invasive procedure and shorter hospital stay are at the expense of more stent reinterventions.

Brady-arrhythmias requiring permanent pacemaker implantation during and after staged Fontan palliation

BACKGROUND

Brady-arrhythmia requiring pacemaker implantation remains one of the Fontan-specific complications before and after total cavopulmonary connection.

METHODS

A retrospective analysis of 620 patients who underwent total cavopulmonary connection between 1994 and 2021 was performed to evaluate the incidence of brady-arrhythmia and the outcomes after pacemaker implantation. Factors associated with the onset of brady-arrhythmia were identified.

RESULTS

A total of 52 patients presented with brady-arrhythmia and required pacemaker implantation. Diagnosis included 16 sinus node dysfunctions, 29 atrioventricular blocks, and 7 junctional escape rhythms. Pacemaker implantation was performed before total cavopulmonary connection (n = 16), concomitant with total cavopulmonary connection (n = 8), or after total cavopulmonary connection (n = 28, median 1.8 years post-operatively). Freedom from pacemaker implantation following total cavopulmonary connection at 10 years was 92%. Twelve patients needed revision of electrodes due to lead dysfunction (n = 9), infections (n = 2), or dislocation (n = 1). Lead energy thresholds were stable, and freedom from pacemaker lead revision at 10 years after total cavopulmonary connection was 78%. Congenitally corrected transposition of the great arteries (odds ratio: 6.6, confidence interval: 2.0-21.5, p = 0.002) was identified as a factor associated with pacemaker implantation before total cavopulmonary connection. Pacemaker rhythms for Fontan circulation were not a risk factor for survival (p = 0.226), protein-losing enteropathy/plastic bronchitis (p = 0.973), or thromboembolic complications (p = 0.424).

CONCLUSIONS

In our cohort of patients following total cavopulmonary connection, freedom from pacemaker implantation at 10 years was 92% and stable atrial and ventricular lead energy thresholds were observed. Congenitally corrected transposition of the great arteries was at increased risk for pacemaker implantation before total cavopulmonary connection. Having a pacemaker in the Fontan circulation had no adverse effect on survival, protein-losing enteropathy/plastic bronchitis, or thromboembolic complications.

Long-Term Survival Is Superior in Patients With Pulsatile Pulmonary Flow After the Björk Procedure

Background: This study aims to evaluate clinical outcomes and hemodynamic variables late after the Björk procedure, regarding the pulmonary flow pattern. Methods: Patients who survived more than 15 years after the Björk procedure were included and then divided into two groups according to their pulmonary flow pattern by pulsed-wave Doppler assessment of echocardiography: patients with pulsatile systolic pulmonary flow (Group P) and those without (Group N). Results: A total of 43 patients were identified, of whom 13 patients were divided into Group P and 30 in Group N. Median age at the Björk procedure was 5.7 (2.1-7.3) years, and median follow-up was 32 (28-36) years. Survival after 15 years was higher in Group P, compared with Group N (100% vs 76% at 30 years, P = .045). Cardiac catheterization data demonstrated higher cardiac index in Group P patients compared with Group N patients (3.5 vs 2.8 L/m2, P = .014). Cardiac magnetic resonance imaging study revealed that Group P patients had higher right ventricular end-diastolic volume index (96 vs 57 mL/m2, P = .005), higher end-systolic volume index (49 vs 30 mL/m2, P = .013) and higher right ventricular stroke volume index (48 vs 25 mL/m2, P < .001), compared with Group N patients. Exercise capacity tests demonstrated that Group P patients showed a higher percent predicted peak oxygen consumption, compared with Group N patients (73 vs 58%, P < .001). Conclusions: Late after the Björk procedure, patients with a pulsatile systolic pulmonary flow had a larger right ventricle and better exercise capacity compared with those without pulsatile systolic pulmonary flow.

Impact of aortopulmonary collaterals on adverse events after total cavopulmonary connection

OBJECTIVES

Effects of aortopulmonary collaterals (APCs) on outcomes after the total cavopulmonary connection (TCPC) are unclear. This study evaluated the incidence of APCs before and after TCPC and analysed the impacts of APCs on adverse outcomes.

METHODS

A total of 585 patients, who underwent TCPC from 1994 to 2020 and whose preoperative angiographies were available, were included. Pre-TCPC angiograms in all patients were used for the detection of APCs, and post-TCPC angiograms were evaluated in selected patients. Late adverse events included late death, protein-losing enteropathy (PLE) and plastic bronchitis (PB).

RESULTS

The median age at TCPC was 2.3 (1.8-3.4) years with a body weight of 12 (11-14) kg. APCs were found in 210 patients (36%) before TCPC and in 81 (14%) after TCPC. The closure of APCs was performed in 59 patients (10%) before TCPC, in 25 (4.2%) at TCPC and in 59 (10%) after TCPC. The occurrences of APCs before and after TCPC were not associated with short-term or mid-term mortality. The APCs before TCPC were associated with chylothorax (P = 0.025), prolonged chest tube duration (P = 0.021) and PB (P = 0.008). The APCs after TCPC were associated with PLE (P < 0.001) and PB (P < 0.001). With APCs following TCPC, freedom from PLE and PB was lower than without (P < 0.001, P < 0.001).

CONCLUSIONS

APCs before TCPC were associated with chylothorax, prolonged chest tube duration and PB. APCs after TCPC were associated with both PLE and PB. The presence of APCs might affect the lymph drainage system and increase the incidence of chylothorax, PLE and PB.

Impact of pulsatile pulmonary blood flow on cardiopulmonary exercise performance after the Fontan procedure

Objective

To evaluate the exercise capacity in patients following Fontan-Kreutzer, Fontan-Björk, and total cavopulmonary connection (TCPC).

Methods

Patients who performed exercise capacity tests at least once after the Fontan procedure between 1979 and 2007 were included. Patients after Fontan-Björk procedure were divided into 2 groups according to the pulmonary blood flow (PBF) pattern: patients with pulsatile PBF and those without. Peak oxygen uptake (VO2) was measured and percent-predicted VO2 was calculated.

Results

A total of 227 patients were nominated. The types of Fontan procedure included Fontan-Kreutzer in 48 (21.1%) patients, Fontan-Björk in 38 (16.7%); 11 (4.8%) with pulsatile PBF and 27 (11.9%) without pulsatile PBF; and TCPC in 141 (62.1%). Median age at the Fontan procedure was 4.5 years (interquartile range, 2.1-8.2 years). A total of 978 cardiopulmonary exercise tests were performed at median follow-up of 17.7 years (interquartile range, 11.3-23.4 years) postoperatively. Analysis using linear mixed-effects models demonstrated that percent-predicted VO2 was greater in patients with pulsatile PBF after Fontan-Björk compared with patients after other types of Fontan procedure (P < .001). The same results were obtained when the longitudinal percent predicted VO2 was performed using only patients with tricuspid atresia and double inlet left ventricle (P < .001).

Conclusions

Among long-term survivors after various types of Fontan procedures, patients with pulsatile PBF after the Fontan-Björk procedure demonstrated better exercise performance compared to those after TCPC, those after the Fontan-Kreutzer procedure, and those after the Fontan-Björk procedure with non-pulsatile PBF. The results implicate the importance of pulsatile PBF to maintain the Fontan circulation.

Mid-term results following pulmonary artery patch augmentation in congenital heart disease

Background

Treatment of pulmonary artery (PA) stenosis in congenital heart disease is associated with adverse outcomes. The aim of this retrospective cohort study was to compare outcomes after surgical patch augmentation of PA stenosis in patients with biventricular congenital heart disease using different patch materials.

Methods

We identified all patients from our institutional congenital heart disease database who underwent patch augmentation for PA stenosis on the main pulmonary artery (MPA) or PA branches between 2012 and 2018. Patch materials used were glutaraldehyde fixated autologous pericardium (AP), expanded polytetrafluoroethylene (ePTFE), equine pericardium (EP), and bovine pericardium (BP). The primary study endpoint was the composite of catheter-based re-intervention or re-operation to relieve recurrent stenosis at the site of prior implanted patch material.

Results

A total of 156 patients (median age, 5 months, range, 0-85 months; median weight, 6.2 kg, range, 2.8-15.0 kg) underwent patch augmentation using 163 patches (ePTFE =99, 61%; EP =34, 21%; AP =25, 15%; BP =5, 3%). Overall, 131 (84%) patients underwent patch augmentation at the MPA, and 25 (16%) patients underwent patch augmentation at one or both PA branches. Over a mean follow-up period of 4±2 years, 30 patients (19%) reached the study endpoint. Freedom from primary endpoint was 92%±3% for the MPA and 25%±9% for PA branches at 5 years, respectively (P<0.001). Comparison of patch materials revealed similar re-intervention rates between ePTFE, AP, and EP. In contrast, outcomes were significantly decreased following the usage of BP when compared to other materials (ePTFE vs. BP, P=0.01; EP vs. BP, P=0.005). In the multivariable analysis, lower weight at index operation, patch augmentation of PA branches, and usage of BP were independently associated with re-intervention.

Conclusions

Patch augmentation of the MPA was associated with acceptable outcomes, while patch augmentation of PA branch stenosis remained independently associated with re-intervention. None of the used patch materials demonstrated superiority; however, BP had a higher rate of re-interventions.

Protein-Losing Enteropathy and Plastic Bronchitis Following the Total Cavopulmonary Connections

BACKGROUND

We aimed to evaluate incidence, outcomes, and predictors of protein-losing enteropathy (PLE) and plastic bronchitis (PB) in a cohort of total cavopulmonary connection (TCPC).

METHODS

We included 620 consecutive patients undergoing TCPC between 1994 and 2021. Prevalence and predictors for onset of PLE/PB were evaluated. Death and heart transplantation after onset of PLE/PB were examined.

RESULTS

A total of 41 patients presented with PLE/PB (31 with PLE, 15 with PB, and 5 developed both PLE and PB). Their median age at TCPC was 2.2 (interquartile ranges [IQRs], 1.7-3.7) years, and time period to onset for PLE was 2.6 (IQR: 1.0-6.6) years and for PB was 1.1 (IQR: 0.3-4.1) years after TCPC. Independent factors for developing PLE/PB were dominant right ventricle (RV, hazard ratio [HR], 2.243; 95% confidence interval [CI], 1.129-4.458, P = .021) and prolonged pleural effusion after TCPC (HR, 2.101; 95% CI, 1.090-4.049, P = .027). In PLE/PB population, freedom from death or transplantation after PLE/PB diagnosis at 5 and 10 years were 88.7% and 76.4%, respectively. Eleven surgical interventions were performed in 10 patients, comprising atrioventricular valve repairs (n = 4), Fontan pathway revisions (n = 2), pacemaker implantation (n = 2), secondary fenestration (n = 1), diaphragm plication (n = 1), and ventricular assist device implantation (n = 1). In nine patients, a recovery from PLE with the resolution of PLE symptoms and normal protein levels was achieved. Eight patients died and the remaining continued to have challenging protein loss.

CONCLUSIONS

Protein-losing enteropathy and PB remain severe complications in the cohort of TCPC. Patients with dominant RV, and prolonged pleural effusions, were at risk for PLE/PB.

Development of Weight and Height Age z-Score after Total Cavopulmonary Connection

OBJECTIVE

 We aimed to analyze somatic growth of patients after total cavopulmonary connection (TCPC) as well as to identify factors influencing postoperative catch-up growth.

METHODS

 A total of 309 patients undergoing TCPC at 4 years old or less between 1994 and 2021 were included. Weight for age z-score (WAZ) and height for age-z-score (HAZ) at TCPC and at postoperative time between 1 and 3 years were calculated. Factors influencing somatic growth were analyzed.

RESULTS

 Most frequent diagnosis and initial palliation were hypoplastic left heart syndrome (HLHS) (34%) and the Norwood procedure (51%), respectively. Median age and weight at TCPC were 2.0 (IQR: 1.7-2.5) years and 11.3 (10.5-12.7) kg, respectively. Median 519 days after TCPC, a significant increase in WAZ (-0.4 to -0.2, p < 0.001) was observed, but not in HAZ (-0.6 to -0.6, p = 0.38). Older age at TCPC (p < 0.001, odds ratio [OR]: 2.6) and HLHS (p = 0.007, OR: 2.2) were risks for low WAZ after TCPC. Older age at TCPC (p = 0.009, OR: 1.9) and previous Norwood procedure (p = 0.021, OR: 2.0) were risks for low HAZ after TCPC. Previous bidirectional cavopulmonary shunt (BCPS) was a protective factor for both WAZ (p = 0.012, OR: 0.06) and HAZ (p = 0.028, OR: 0.30) at TCPC.

CONCLUSION

 In patients undergoing TCPC at the age of 4 years or less, a significant catch-up growth was observed in WAZ after TCPC, but not in HAZ. Previous BCPS resulted to be a protective factor for a better somatic development at TCPC. HLHSs undergoing Norwood were considered as risks for somatic development after TCPC.

Impact of home monitoring program on interstage mortality after the Norwood procedure

Objective

While early outcome after the Norwood operation for hypoplastic left heart syndrome has improved, interstage mortality until bidirectional cavopulmonary shunt (BCPS) remains a concern. Our aim was to institute a home monitoring program to (HMP) decrease interstage mortality.

Methods

Among 264 patients who survived Norwood procedure and were discharged before BCPS, 80 patients were included in the HMP and compared to the remaining 184 patients regarding interstage mortality. In patients with HMP, events during the interstage period were evaluated.

Results

Interstage mortality was 8% (n = 21), and was significantly lower in patients with HMP (2.5%, n = 2), compared to those without (10.3%, n = 19, p = 0.031). Patients with interstage mortality had significantly lower birth weight (p < 0.001) compared to those without. Lower birth weight (p < 0.001), extra corporeal membrane oxygenation support (p = 0.002), and lack of HMP (p = 0.048) were risk factors for interstage mortality. Most frequent event during home monitoring was low saturation (<70%) in 14 patients (18%), followed by infection in 6 (7.5%), stagnated weight gain in 5 (6.3%), hypoxic shock in 3 (3.8%) and arrhythmias in 2 (2.5%). An unexpected readmission was needed in 24 patients (30%). In those patients, age (p = 0.001) and weight at BCPS (p = 0.007) were significantly lower compared to those without readmission, but the survival after BCPS was comparable between the groups.

Conclusions

Interstage HMP permits timely intervention and led to an important decrease in interstage mortality. One-third of the patients with home monitoring program needed re-admission and demonstrated the need for earlier stage 2 palliation.

Multiscale multimodal characterization and simulation of structural alterations in failed bioprosthetic heart valves

Calcific degeneration is the most frequent type of heart valve failure, with rising incidence due to the ageing population. The gold standard treatment to date is valve replacement. Unfortunately, calcification oftentimes re-occurs in bioprosthetic substitutes, with the governing processes remaining poorly understood. Here, we present a multiscale, multimodal analysis of disturbances and extensive mineralisation of the collagen network in failed bioprosthetic bovine pericardium valve explants with full histoanatomical context. In addition to highly abundant mineralized collagen fibres and fibrils, calcified micron-sized particles previously discovered in native valves were also prevalent on the aortic as well as the ventricular surface of bioprosthetic valves. The two mineral types (fibres and particles) were detectable even in early-stage mineralisation, prior to any macroscopic calcification. Based on multiscale multimodal characterisation and high-fidelity simulations, we demonstrate that mineral occurrence coincides with regions exposed to high haemodynamic and biomechanical indicators. These insights obtained by multiscale analysis of failed bioprosthetic valves serve as groundwork for the evidence-based development of more durable alternatives. STATEMENT OF SIGNIFICANCE: Bioprosthetic valve calcification is a well-known clinically significant phenomenon, leading to valve failure. The nanoanalytical characterisation of bioprosthetic valves gives insights into the highly abundant, extensive calcification and disorganization of the collagen network and the presence of calcium phosphate particles previously reported in native cardiovascular tissues. While the collagen matrix mineralisation can be primarily attributed to a combination of chemical and mechanical alterations, the calcified particles are likely of host cellular origin. This work presents a straightforward route to mineral identification and characterization at high resolution and sensitivity, and with full histoanatomical context and correlation to hemodynamic and biomechanical indicators, hence providing design cues for improved bioprosthetic valve alternatives.

Outcome of Stanford type B dissection in patients with Marfan syndrome

OBJECTIVES

The aim of this study was to determine the outcome of Stanford type B aortic dissection in patients with Marfan syndrome (MFS) and to evaluate aortic diameters at time of dissection as well as the impact of previous aortic root replacement.

METHODS

Analysis of all patients with MFS fulfilling Ghent criteria seen at this institution since 1995 until 2022.

RESULTS

Thirty-six (19%) out of 188 patients with MFS suffered from Stanford type B aortic dissection during the study period. The Mean aortic diameter at the time of dissection was 39.0 mm [95% confidence interval (CI): 35.6-42.3]. The mean pre-dissection diameter (available in 25% of patients) was 32.1 mm (95% CI: 28.0-36.3) and the mean expansion was 19% (95% CI: 11.9-26.2). There was no correlation between age and diameter at the time of dissection (<20, 21-30, 31-40, 41-50, 51-60, <61 years; P = 0.78). Freedom from intervention after dissection was 53%, 44% and 33% at 1, 5 and 10 years. Aortic growth rate in those patients that had to undergo intervention within the 1st year after dissection was 10.2 mm/year (95% CI: 4.4-15.9) compared to 5.8 mm/year (95% CI: 3.3-8.3, P = 0.109) in those thereafter. The mean time between dissection and intervention was 1.8 years (95% CI: 0.6-3.0). While type B dissection seems more frequent after previous elective aortic repair (58% vs 42%), there was no difference between valve-sparing root replacement (VSRR) compared to Bentall procedures [Hazard ratio (HR) for VSRR 0.78, 95% CI: 0.31-2.0, P-value = 0.61]. The mean age of the entire population at the end of follow-up was 42 years (95% CI: 39.2-44.7). The mean follow-up time was 9 years (95% CI: 7.8-10.4).

CONCLUSIONS

Stanford type B dissection in patients with MFS occurs far below accepted thresholds for intervention. Risk for type B dissection is present throughout lifetime and two-thirds of patients need an intervention after dissection. There is no difference in freedom from type B dissection between a Bentall procedure and a VSRR.

Biogenic polymer-based patches for congenital cardiac surgery: a feasibility study

Objective

Currently used patch materials in congenital cardiac surgery do not grow, renew, or remodel. Patch calcification occurs more rapidly in pediatric patients eventually leading to reoperations. Bacterial cellulose (BC) as a biogenic polymer offers high tensile strength, biocompatibility, and hemocompatibility. Thus, we further investigated the biomechanical properties of BC for use as patch material.

Methods

The BC-producing bacteria Acetobacter xylinum were cultured in different environments to investigate optimal culturing conditions. For mechanical characterization, an established method of inflation for biaxial testing was used. The applied static pressure and deflection height of the BC patch were measured. Furthermore, a displacement and strain distribution analysis was performed and compared to a standard xenograft pericardial patch.

Results

The examination of the culturing conditions revealed that the BC became homogenous and stable when cultivated at 29°C, 60% oxygen concentration, and culturing medium exchange every third day for a total culturing period of 12 days. The estimated elastic modulus of the BC patches ranged from 200 to 530 MPa compared to 230 MPa for the pericardial patch. The strain distributions, calculated from preloaded (2 mmHg) to 80 mmHg inflation, show BC patch strains ranging between 0.6% and 4%, which was comparable to the pericardial patch. However, the pressure at rupture and peak deflection height varied greatly, ranging from 67 to around 200 mmHg and 0.96 to 5.28 mm, respectively. The same patch thickness does not automatically result in the same material properties indicating that the manufacturing conditions have a significant impact on durability.

Conclusions

BC patches can achieve comparable results to pericardial patches in terms of strain behavior as well as in the maximum applied pressure that can be withstood without rupture. Bacterial cellulose patches could be a promising material worth further research.

A novel soft cardiac assist device based on a dielectric elastomer augmented aorta: An in vivo study

Although heart transplant is the preferred solution for patients suffering from heart failures, cardiac assist devices remain key substitute therapies. Among them, aortic augmentation using dielectric elastomer actuators (DEAs) might be an alternative technological application for the future. The electrically driven actuator does not require bulky pneumatic elements (such as conventional intra-aortic balloon pumps) and conforms tightly to the aorta thanks to the manufacturing method presented here. In this study, the proposed DEA-based device replaces a section of the aorta and acts as a counterpulsation device. The feasibility and validation of in vivo implantation of the device into the descending aorta in a porcine model, and the level of support provided to the heart are investigated. Additionally, the influence of the activation profile and delay compared to the start of systole is studied. We demonstrate that an activation of the DEA just before the start of systole (30 ms at 100 bpm) and deactivation just after the start of diastole (0-30 ms) leads to an optimal assistance of the heart with a maximum energy provided by the DEA. The end-diastolic and left ventricular pressures were lowered by up to 5% and 1%, respectively, compared to baseline. The early diastolic pressure was augmented in average by up to 2%.

Longitudinal analysis of systemic ventricular function and atrioventricular valve function after the Fontan procedure

OBJECTIVE

This study aimed to determine the longitudinal change of systemic ventricular function and atrioventricular valve regurgitation after total cavopulmonary connection.

METHODS

In 620 patients who underwent total cavopulmonary connection between 1994 and 2021, 4219 longitudinal echocardiographic examinations of systemic ventricular function and atrioventricular valve regurgitation were evaluated retrospectively.

RESULTS

The most frequent primary diagnosis was hypoplastic left heart syndrome in 172, followed by single ventricle in 131, tricuspid atresia in 95, and double inlet left ventricle in 91 patients. Dominant right ventricle was observed in 329 (53%) and dominant left ventricle in 291 (47%). Median age at total cavopulmonary connection was 2.3 (1.8-3.4) years. Transplant-free survival at 5, 10, and 15 years after total cavopulmonary connection was 96.3, 94.7, and 93.6%, respectively in patients with dominant right ventricle and 97.3, 94.6, and 94.6%, respectively in those with dominant left ventricle (p = 0.987). Longitudinal analysis of systemic ventricular function was similar in both groups during the first 10 years postoperatively. Thereafter, systemic ventricular function worsened significantly in patients with dominant right ventricle, compared with those with dominant left ventricle (15 years: p = 0.007, 20 years: p = 0.03). Atrioventricular valve regurgitation was more frequent after total cavopulmonary connection in patients with dominant right ventricle compared with those with dominant left ventricle (p < 0.001 at 3 months, 3 years, 5 years, 10 years, and 15 years, p = 0.023 at 20 years). There was a significant correlation between postoperative systemic ventricular dysfunction and atrioventricular valve regurgitation (p < 0.001).

CONCLUSIONS

There was no transplant-free survival difference and no difference in ventricular function between dominant right ventricle and dominant left ventricle for the first 10 years after total cavopulmonary connection. Thereafter, ventricular function in dominant right ventricle was inferior to that in dominant left ventricle. The degree of atrioventricular valve regurgitation was significantly higher in dominant right ventricle, compared with dominant left ventricle, and it was positively associated with ventricular dysfunction, especially in dominant right ventricle.

Changes in pulmonary artery index and its relation to outcome after stage II palliation in patients with hypoplastic left heart syndrome

OBJECTIVE

This study aimed to prove if pulmonary artery size influences survival and if an additional aortopulmonary shunt promotes left pulmonary artery growth after bidirectional cavopulmonary shunt in patients with hypoplastic left heart syndrome.

METHODS

The medical records of patients with hypoplastic left heart syndrome who underwent Norwood procedure and bidirectional cavopulmonary shunt between 2007 and 2020 were reviewed. Right, left, and total (right + left) pulmonary artery indices were calculated according to Nakata and colleagues.

RESULTS

A total of 158 patients were included in this study. Median age at Norwood and bidirectional cavopulmonary shunt was 8 (7-11) days and 3.6 (3.1-4.6) months, respectively. There were 7 hospital deaths and 12 late deaths. Survival after bidirectional cavopulmonary shunt was 90.3% at 1 year, and 86.2% at 2 years. Total, right, and left pulmonary artery indices were 238 (195-316), 136 (101-185), and 102 (75-130) mm2/m2 at the time of bidirectional cavopulmonary shunt, and they were 237 (198-284), 151 (123-186), and 86 (69-108) mm2/m2 at the time of Fontan. Left pulmonary artery index decreased significantly between the time of bidirectional cavopulmonary shunt and Fontan (p < 0.01). Nine patients needed partial takedown and additional aortopulmonary shunt due to failing bidirectional cavopulmonary shunt, but the additional aortopulmonary shunt did not promote the pulmonary artery growth significantly.

CONCLUSIONS

Preoperative pulmonary artery index did not affect the mortality after bidirectional cavopulmonary shunt. The partial takedown and additional aortopulmonary shunt for failing bidirectional cavopulmonary shunt were unable to improve left pulmonary artery size.

Impact of Extracardiac Anomalies on Mortality and Morbidity in Staged Single Ventricle Palliation

BACKGROUND

This study was intended to determine the impact of extracardiac anomalies on outcomes in patients with functional single ventricle who underwent staged palliation.

METHODS

We reviewed medical records of patients who underwent first-stage palliation at our center between 2001 and 2020. The prevalence and type of extracardiac anomalies were evaluated, and their impact on outcomes during staged palliation was analyzed.

RESULTS

Among 602 patients who underwent first-stage palliation, 81 (14%) patients had associated with extracardiac anomalies. They were more frequently associated with prematurity (P = .03) and low birth weight below 2.5 kg (P < .01). Mortality between first-stage palliation and stage II was similar in patients with and without extracardiac anomalies (24.7% vs 17.1%, P = .10). However, mortality between stage II and stage III was significantly higher in patients with extracardiac anomalies compared with those without (22.2% vs 12.5%, P = .02). Mortality after stage III was also higher in patients with extracardiac anomalies compared with those without (4.9% vs 1.5%, P = .04). In the subgroup analysis of 81 patients with extracardiac anomalies, renal anomalies were identified as a significant risk factor for mortality (P = .03, hazard ratio 2.44).

CONCLUSIONS

The incidence of extracardiac anomalies in this study was 14%, and patients with extracardiac anomalies were highly associated with prematurity and low birth weight. Presence of extracardiac anomalies was associated with higher mortality between stage II and stage III palliation and after stage III phase, but not before stage II. Among extracardiac anomalies, renal anomalies were identified as a risk factor for mortality.

Outcome after stage 1 palliation in non-hypoplastic left heart syndrome patients as a univentricular palliation

OBJECTIVES

Studies focused on infants with univentricular heart undergoing stage I palliation other than the Norwood procedure remain a topic of great interest. This study evaluated the outcome of infants who underwent systemic to pulmonary shunt (SPS) or pulmonary artery banding (PAB).

METHODS

Infants who underwent SPS or PAB as stage I palliation between 1994 and 2019 were included. Survival and late systemic ventricular function were evaluated.

RESULTS

Out of 242 patients, 188 underwent SPS (77.7%) and 54 PAB (22.3%). Main diagnosis included tricuspid atresia, unbalanced atrioventricular septal defects, double inlet left ventricles and single ventricles with other morphology. Thirty-eight patients died before stage II palliation (15.7%). Stage II palliation was performed in 182 patients (75.2%), and mortality between stages II and III was 11 (5.6%). Stage III palliation was performed in 160 (66.1%) patients. Survival at 1, 5 and 15 years after stage I procedure was 81.9, 77.1 and 76.2%, respectively, and similar between both procedures (P = 0.97). Premature birth [P = 0.03, hazard ratio (HR) = 2.1], heterotaxy (P = 0.006, HR = 2.4) and dominant right ventricle (P = 0.015, HR = 2.2) were factors associated to mortality. Unbalanced atrioventricular septal defect (P = 0.005, HR = 4.6) was a factor associated to systemic ventricular dysfunction.

CONCLUSIONS

In patients with univentricular heart who underwent SPS and PAB as stage I palliation, survival at 15 years was 76%, regardless of th chosen approach. Premature birth, heterotaxy and dominant right ventricle were associated to mortality.

Pleural and mediastinal effusions after the extracardiac total cavopulmonary connection: Risk factors and impact on outcome

Background

This study investigated the volume and duration of pleural and mediastinal effusions following extracardiac total cavopulmonary connection, as well as preoperative risk factors and their impact on outcome.

Materials and methods

A total of 210 patients who underwent extracardiac total cavopulmonary connection at our center between 2012 and 2020 were included in this study. Postoperative daily amount of pleural and mediastinal drainage were collected and factors influencing duration and amount of effusions were analyzed. The impact of effusions on adverse events was analyzed.

Results

Median age at extracardiac total cavopulmonary connection was 2.2 (interquartile range, 1.8–2.7) years with median weight of 11.6 (10.7–13.0) kg. Overall duration of drainage after extracardiac total cavopulmonary connection was 9 (6–17) days. The total volume of mediastinal, right pleural, and left pleural drainage was 18.8 (11.9–36.7), 64.4 (27.4–125.9), and 13.6 (0.0–53.5) mL/kg, respectively. Hypoplastic left heart syndrome (p = 0.004) and end-diastolic pressure (p = 0.044) were associated with high volume of drainages, and hypoplastic left heart syndrome (p = 0.007), presence of aortopulmonary collaterals (p = 0.002), and high end-diastolic pressure (p = 0.023) were associated with long duration of drainages. Dextrocardia was associated with higher volume (p &lt; 0.001) and longer duration (p = 0.006) of left pleural drainage. Duration of drainage was associated with adverse events following extracardiac total cavopulmonary connection (p = 0.015).

Conclusion

Volume and duration of pleural and mediastinal effusions following extracardiac total cavopulmonary connection were related with hypoplastic left heart syndrome, aortopulmonary collaterals, and end-diastolic pressure. The duration of drainage for effusions was a risk factor for adverse events after total cavopulmonary connection.

Becoming a congenital heart surgeon: the long and challenging road

Training in congenital cardiac surgery is potentially lengthier and more demanding than training in any other surgical field. The duration of training is proportional to the complexity of the specialization. The expertise of a wide range of procedures is required. There is no doubt that some individuals may acquire the requisite abilities with greater ease than others, but fundamentally, these are capabilities that can be taught and learnt. Moreover, congenital cardiac surgeons are required to have a detailed understanding of pathophysiology and morphology, in addition to the stamina and empathy required to manage these complex patients. A fellowship is just the start of such training and is followed by a long road eventually leading to a lifelong journey to become a qualified congenital cardiac surgeon. Effective mentorship is a prerequisite throughout training to guide surgeons on this journey.

The impact of pulmonary artery size on mid-term outcomes after non-fenestrated Fontan operation

OBJECTIVE

We sought to identify the impact of pulmonary artery size on outcomes after nonfenestrated total cavopulmonary connection. In a subgroup of patients with right-sided bidirectional cavopulmonary shunt, the impact of each branch pulmonary artery size was individually determined.

METHODS

The medical records of all patients who underwent nonfenestrated total cavopulmonary connection between 2009 and 2021 were reviewed. The pulmonary artery index was calculated using angiography before the operation.

RESULTS

A total of 247 patients were included in this study. A right-sided bidirectional cavopulmonary shunt was performed in 217 patients (88%). Median pulmonary artery index was 162 (133-207) mm²/m² before total cavopulmonary connection. Chylothorax occurred in 55 patients (22%). Pulmonary artery index was an independent factor for chylothorax (odds ratio, 0.98, 95% confidence interval, 0.97-0.99, P < .001) with a cutoff value of 170 mm²/m². In a subgroup of patients with right-sided bidirectional cavopulmonary shunt, the left pulmonary artery index was identified as an independent risk factor for longer stay in the intensive care unit (coefficient B -0.02, 95% confidence interval, -0.04 to -0.002, P = .034) and for adverse events (hazard ratio, 0.98, 95% confidence interval, 0.96-0.99, P = .011) with a cutoff value of 56 mm²/m².

CONCLUSIONS

The pulmonary artery index is significantly associated with the occurrence of chylothorax after nonfenestrated total cavopulmonary connection with a cutoff value of 170 mm²/m². In patients with right-sided bidirectional cavopulmonary shunt, left pulmonary artery index has a significant predictive value for longer stay in the intensive care unit and adverse events with a cutoff value of 56 mm²/m².

Management of failing bidirectional cavopulmonary shunt: Influence of additional systemic-to-pulmonary-artery shunt with classic Glenn physiology

Objectives

Methods

Results

Conclusions

Impact of Anatomical Sub-types and Shunt Types on Aortopulmonary Collaterals in Hypoplastic Left Heart Syndrome

This study aims to clarify the relation of development of aortopulmonary collateral arteries (APCs) with anatomical sub-types and the shunt types at Norwood procedure in patients with hypoplastic left heart syndrome (HLHS). A total of 140 patients with HLHS who completed 3 staged palliation between 2003 and 2019 were included. Incidence of APCs and corresponding interventions were examined using angiogram by cardiac catheterization, with respect to the anatomical sub-types and shunt types. Totally, APCs were observed in 87 (62%) of the patients; pre-stage II in 32 (23%), pre-stage III in 64 (46%), and after stage III in 40 (29%). The incidence of APCs before stage II was significantly higher in patients with aortic atresia/mitral atresia (AA/MA) compared with other sub-types (P = 0.022). Patients with right ventricle to pulmonary artery conduit (RVPAC) had a higher incidence of APCs originating from the descending aorta, compared with those with modified Blalock-Taussig shunt (20% vs 2%, P= 0.002). Interventions for APCs were performed in 58 (41%) patients; before stage II in 10 (7%), after stage II in 7 (5%), before stage III in 22 (16%), and after stage III in 32 (23%). Patients with AA/MA had more interventions before stage II (P= 0.019), and patients with aortic stenosis/mitral stenosis (AS/MS) had a lower incidence of interventions after stage III (P= 0.047). More than half of the patients with HLHS developed APCs. Before stage II, patients with AA/MA sub-type had a higher incidence of APCs, and those with RVPAC had significantly more APCs from the descending aorta.

Impact of total anomalous pulmonary venous connection in staged single ventricle palliation

BACKGROUND

Total anomalous pulmonary venous connection (TAPVC) with a functional single ventricle is a risk factor for mortality during staged palliation. This study aimed to assess TAPVC's impact on staged palliation outcomes.

METHODS

In a total of 602 patients with a functional single ventricle who underwent stage 1 palliation (S1P) at our center between 2001 and 2020, 39 (6.5%) patients were associated with TAPVC. Median age at S1P was 12.0 (interquartile range, 7-21) days with a body weight of 3.1 (interquartile range, 2.8-3.6) kg. Outcomes during staged palliation were compared with the remaining 563 patients without TAPVC. Risk factors for mortality were identified using a Cox proportional hazards regression model.

RESULTS

Primary diagnosis in functional single-ventricle patients with TAPVC included hypoplastic left heart syndromes (n = 13), unbalanced atrioventricular septal defects (n = 12) tricuspid atresias (n = 2), double inlet left ventricle (n = 1), and others (n = 11). Types of TAPVC were supracardiac (n = 21), cardiac (n = 10), infracardiac (n = 6), and mixed (n = 2). Pulmonary venous obstruction (PVO) was associated in 19 (49%) patients. S1Ps included Norwood (n = 13), aortopulmonary shunt (n = 21), and pulmonary artery banding (n = 5). Thirty-day mortality after S1P was significantly increased in patients with TAPVC vs without TAPVC (43.6% vs 16.3%; P < .001). After bidirectional cavopulmonary shunt and total cavopulmonary connection procedures, mortality was low in both groups, and no statistically significant differences were found. Correction of TAPVC at the time of S1P was not found to be a significant risk factor in univariable Cox regression analysis. In univariate and multivariate analysis, PVO was identified as an independent risk factor for mortality in patients with TAPVC (P < .001).

CONCLUSIONS

Overall survival is lower in TAPVC single-ventricle patients than in non-TAPVC patients. Most deaths after S1P were associated with TAPVC, but not after S2P. PVO is a mortality risk factor in TAPVC patients.

Third-generation continuous-flow left ventricular assist devices: a comparative outcome analysis by device type

AIMS

Continuous-flow left ventricular assist devices (CF-LVADs) have become a standard of care in end-stage heart failure. Limited data exist comparing outcomes of HeartMate3 (HM3) and HeartWare HVAD (HW). We aimed to compare midterm outcomes of these devices.

METHODS AND RESULTS

Investigator-initiated retrospective-observational comparative analysis of all patients who underwent primary LVAD implantation of either HM3 or HW at our centre between January 2010 and December 2020. Data were derived from a prospective registry. Primary endpoints were all-cause mortality and heart transplantation. Secondary endpoints included device-related major adverse cardiac and cerebrovascular events, which included major bleeding, major neurological dysfunction (defined as persisting neurological impairment for ≥24 h), device-related major infection (excluding driveline infections), major device malfunctions leading to re-intervention or partial device exchange (pump failure, outflow-graft twist or failure, controller failure, battery failure, patient cable failure, but excluding pump thrombosis), and pump thrombosis. Further secondary endpoints included right heart failure, gastrointestinal bleeding, driveline infections, and surgical re-interventions. The secondary outcomes were analysed not only for the first event but also for recurrent events. The analysis included competing risks analysis and recurrent event regression analysis, with adjustment for confounders age, gender, body mass index (BMI), and Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) level. Out of 106 primary CF-LVAD implantations, 36 (34%) received HM3 and 70 (66%) received HW. Median follow-up was 1.48 years [interquartile range 0.67, 2.41]. HM3 was more often implanted in men (91.7% vs. 72.9%, P = 0.024); patients were older (median 61 years [54, 66.5] vs. 52.5 years [43, 60], P < 0.001), had a higher BMI (median 26.7 kg/m² [23.4, 29.0] vs. 24.3 kg/m² [20.7, 27.4], P = 0.013), had more comorbidities, and were more likely targeted for destination therapy (36.1% vs. 14.3%, P = 0.010). Death occurred in 33.3% of HM3 patients, compared with 22.9% of HW patients, P = 0.247 (probability of survival at 4 years, 54.7% vs. 74.1%, P = 0.296). After adjustment for confounders, we observed a significant six-fold risk increase in device malfunctions for HW [hazard ratio (HR) 6.49, 95% confidence interval (CI) [1.89, 22.32], P = 0.003], but no significant differences in pump thrombosis (P = 0.173) or overall survival (P = 0.801).

CONCLUSIONS

Comparing midterm outcomes between HM3 and HW for LVAD support from a prospective registry, HW patients had a significantly higher risk of device malfunctions. No significant differences were evident between devices in overall survival and in respect to most outcomes.

Clinical and haemodynamic variables associated with intensive care unit length of stay and early adverse outcomes after the Norwood procedure

OBJECTIVES

This study was performed to determine the clinical and haemodynamic variables associated with early adverse outcomes after the neonatal Norwood procedure.

METHODS

Patients who underwent the neonatal Norwood procedure between 2001 and 2019 were included. The patient diagnosis, morphological characteristics and haemodynamic parameters were analysed to identify factors associated with length of stay (LOS) in the intensive care unit (ICU) and mortality during the stay.

RESULTS

A total of 322 patients were depicted. The median age and weight at the Norwood procedure were 9 days and 3.2 kg, respectively. Certain morphological and preoperative parameters, such as birth weight below 2.5 kg, restrictive atrial septal defect, extracardiac anomalies and the diameter of the ascending aorta, were found to be associated with the LOS in the ICU. Analysis using early postoperative haemodynamic variables revealed that systolic arterial pressure, diastolic arterial pressure, serum lactate levels and reduced ventricular function at 2 days postoperatively were associated with the LOS in the ICU. Birth weight <2.5 kg (P = 0.010), a restrictive atrial septal defect (P = 0.001) and smaller ascending aorta (P = 0.039) were associated with death in the ICU. Reduced ventricular function, lower systolic aortic pressure and higher lactate levels at various time points (P < 0.05) were also associated with ICU deaths. The LOS in the ICU was significantly associated with late mortality (P < 0.001, Hazard Ratio (HR) = 1.015).

CONCLUSIONS

The LOS in the ICU after the Norwood procedure was predicted by early postoperative haemodynamic variables, suggesting that good early postoperative haemodynamics determine early recovery. A prolonged stay in the ICU after the Norwood procedure was associated with late mortality.

Endothelial Progenitor Cells as Biomarkers of Cardiovascular Pathologies: A Narrative Review

Endothelial progenitor cells (EPC) may influence the integrity and stability of the vascular endothelium. The association of an altered total EPC number and function with cardiovascular diseases (CVD) and risk factors (CVF) was discussed; however, their role and applicability as biomarkers for clinical purposes have not yet been defined. Endothelial dysfunction is one of the key mechanisms in CVD. The assessment of endothelial dysfunction in vivo remains a major challenge, especially for a clinical evaluation of the need for therapeutic interventions or for primary prevention of CVD. One of the main challenges is the heterogeneity of this particular cell population. Endothelial cells (EC) can become senescent, and the majority of circulating endothelial cells (CEC) show evidence of apoptosis or necrosis. There are a few viable CECs that have properties similar to those of an endothelial progenitor cell. To use EPC levels as a biomarker for vascular function and cumulative cardiovascular risk, a correct definition of their phenotype, as well as an update on the clinical application and practicability of current isolation methods, are an urgent priority.

The impact of on-site cardiac rhythm on mortality in patients supported with extracorporeal cardiopulmonary resuscitation: A retrospective cohort study

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) is increasingly used in patients with out-of-hospital or in-hospital cardiac arrest in whom conventional cardiopulmonary resuscitation remains unsuccessful. The aim of this study was to analyze the impact of initial cardiac rhythm-detected on-site of the cardiac arrest-on mortality.

METHODS

We performed a retrospective cohort study of patients who received ECPR in our tertiary care cardiac arrest center. Patients were divided into three groups depending on their cardiac rhythm: shockable rhythm, pulseless electrical activity, and asystole. The primary endpoint was mortality within the first 7 days after ECPR deployment. Secondary endpoints were mortality within 28 days and the impact of pre-ECPR potassium, serum lactate, pH, and pCO₂ on mortality. The association of the initial cardiac rhythm and the location of arrhythmia detection (patient monitored in hospital [category: monitored], not monitored but hospitalized [in-hospital], not monitored, not hospitalized [out-of hospital]) with the primary and secondary outcome was examined by means of univariable and multivariable logistic regression.

RESULTS

Sixty-five patients could be included in the final analysis. Thirty-two patients (49.2%, 95%CI 36.6%-61.9%) died within the first 7 days. In terms of 7-day-mortality patients differed in the initial cardiac rhythm (p = 0.040) and with respect to the location of arrhythmia detection (p = 0.002). Shockable cardiac rhythm (crude OR 0.21; 95%CI 0.03-0.98) and pulseless electrical activity (0.13; 0.02-0.61) as the initial rhythm on-site showed better odds for survival compared to asystole. However, this association did neither persist in adjusted analysis nor pairwise comparison.

DISCUSSION

The study could not demonstrate a better outcome with shockable rhythm after ECPR. More homogeneous and adequately powered cohorts are needed to better understand the impact of cardiac rhythm on patient outcomes after ECPR.

Experimental validation of a mean systemic pressure analog against zero-flow measurements in porcine VA-ECMO

The mean systemic pressure analog (Pmsa), calculated from running hemodynamic data, estimates mean systemic filling pressure (MSFP). This post hoc study used data from a porcine veno-arterial extracorporeal membrane oxygenation (ECMO) model [n = 9; Sus scrofa domesticus; ES breed (Schweizer Edelschwein)] with eight experimental conditions; Euvolemia [a volume state where ECMO flow produced normal mixed venous saturation (SVO2) without vascular collapse]; three levels of increasing norepinephrine infusion (Vasoconstriction 1-3); status after stopping norepinephrine (Post Vasoconstriction); and three steps of volume expansion (10 mL/kg crystalloid bolus) (Volume Expansion 1-3). In each condition, Pmsa and a "reduced-pump-speed-Pmsa" (Pmsared) were calculated from baseline and briefly reduced pump speeds, respectively. We calculated agreement for absolute values (per condition) and changes (between consecutive conditions) of Pmsa and Pmsared, against MSFP at zero ECMO flow. Euvolemia venous return driving pressure was 5.1 ± 2.0 mmHg. Bland-Altman analysis for Pmsa vs. MSFP (all conditions; 72 data pairs) showed bias (confidence interval) 0.5 (0.1-0.9) mmHg; limits of agreement (LoA) -2.7 to 3.8 mmHg. Bias for ΔPmsa vs. ΔMSFP (63 data pairs): 0.2 (-0.2 to 0.6) mmHg, LoA -3.2 to 3.6 mmHg. Bias for Pmsared vs. MSFP (72 data pairs): 0.0 (-0.3 to -0.3) mmHg; LoA -2.3 to 2.4 mmHg. Bias for ΔPmsared vs. ΔMSFP (63 data pairs) was 0.2 (-0.1 to 0.4) mmHg; LoA -1.8 to 2.1 mmHg. In conclusion, during veno-arterial ECMO, under clinically relevant levels of vasoconstriction and volume expansion, Pmsa accurately estimated absolute and changing values of MSFP, with low between-method precision. The within-method precision of Pmsa was excellent, with a least significant change of 0.15 mmHg.NEW & NOTEWORTHY This is the first study ever to validate the mean systemic pressure analog (Pmsa) against the reference mean systemic filling pressure (MSFP) determined at full arterio-venous pressure equilibrium. Using a porcine ECMO model with clinically relevant levels of vasoconstriction and volume expansion, we showed that Pmsa accurately estimated absolute and changing values of MSFP, with a poor between-method precision. The within-method precision of Pmsa was excellent.

Surgical reintervention on the neo-aorta after the Norwood operation

OBJECTIVES

We sought to identify the prevalence of surgical reintervention on the neo-aorta after Norwood procedure and its impact on long-term outcomes.

METHODS

We reviewed the medical records of all patients who underwent Norwood procedure. The impacts of surgical neoaortic reintervention on outcomes were analysed in each stage of palliation.

RESULTS

A total of 335 patients were included in this study. Thirty patients underwent surgical reintervention on the neo-aorta after Norwood procedure. The timing of initial reintervention was before stage II in 13 patients, at stage II in 7, between stage II and stage III in 5, at stage III in 3 and after stage III in 2. A reintervention before stage II was significantly associated with mortality (HR 14.4, 95% confidence interval 6.00-34.6, P < 0.001). In patients who underwent stage II (n = 251), reintervention had no significant impact on mortality. In patients who underwent stage III (n = 188), the previous reintervention was significantly associated with higher mean pulmonary pressure (P = 0.05) and a higher rate of reduced ventricular function (P = 0.002). Greater than mild atrioventricular valve regurgitation was significantly associated with the development of a neoaortic arch stenosis after stage II (P = 0.03).

CONCLUSIONS

Surgical reinterventions on the neo-aorta were required in each inter-stage phase. A surgical neoaortic reintervention was not related to increased mortality after stage II but significantly associated with a higher rate of reduced ventricular function and elevated mean pulmonary artery pressure.

Ventricular assist device for Fontan: who, when and why?

PURPOSE OF REVIEW

Since the advent of the Fontan palliation, survival of patients with univentricular congenital heart disease has increased significantly. These patients will, however, ultimately develop heart failure requiring advanced therapies such as heart transplantation. As wait times are long, mechanical circulatory support (MCS) is an attractive therapy, both for bridge to transplantation and destination therapy in patients not suitable for transplantation. This review aims to summarize current thinking about how to determine which patients would benefit from a ventricular assist device (VAD), the optimal time for implantation and which device should be considered.

RECENT FINDINGS

VAD implantation in end-stage Fontan is still in its infancy; however, case reports and research interest have increased extensively in the past few years. Mortality is significantly higher than in noncongenital heart disease patients. Implantation in patients with primarily systolic dysfunction is indicated, whereas patients with increased transpulmonary gradient may not benefit from a single-VAD solution. When possible, implantation should occur prior to clinical decompensation with evidence of end-organ damage, as outcomes at this point are worse.

SUMMARY

Fontan patients demonstrating signs of heart failure should be evaluated early and often for feasibility and optimal timing of VAD implantation. The frequency of this procedure will likely increase significantly in the future.

Indoleamine-2,3-Dioxygenase as a Perioperative Marker of the Immune System

Indoleamine-2,3-dioxygenase (IDO) is the “rate-limiting” enzyme in the kynurenine (Kyn) pathway of the tryptophan (Trp) catabolism. By its immune-modulatory effect, IDO initiates changes to the physiologically balanced immune state and plays a key role in the pathogenesis of various diseases, as well as in the perioperative setting during surgery. In autoimmune processes, highly malignant cancers such as glioblastoma or organ transplantation, IDO’s involvement has been studied extensively. However, in severe systemic infections, as present in sepsis, it is not yet completely understood. Hereafter, in this narrative review, we present the current knowledge of IDO’s implication on such complex immune-related processes. Moreover, we address the role of IDO as a predictive biomarker as well as a therapeutic target for immune-mediated diseases. Finally, we discuss IDO in the setting of surgical trauma-induced stress and highlight its promising use as a biomarker in the pre-operative setting for all disciplines involved in the decision-making process and treatment of patients undergoing surgery.

Right ventricular function in Marfan patients remains stable despite (multiple) cardiac interventions

Background

Left-sided heart lesions, namely aortic root aneurysm, mitral valve prolapse and intrinsic left ventricular (LV) dysfunction are an essential part of the cardiovascular phenotype of Marfan syndrome (MFS). While recent data stresses the need for concomitant tricuspid valve repair (TVR) when addressing left-sided heart lesions in non-MFS patients, data on tricuspid valve disease and right ventricular (RV) function in MFS is scarce.

Purpose

We sought to determine changes in RV function, tricuspid valve regurgitation and need for TVR in MFS patients throughout their lifetime, from day of first contact.

Methods

We retrospectively analyzed 183 MFS patients fulfilling Ghent criteria seen at our institution between 1995 and 2019. In this patient population, 136 patients (74%) underwent 170 procedures with cardioplegic arrest. Aortic root surgery was performed in 90% and mitral valve surgery (MVR) in 19% of patients undergoing surgery. TVR was performed in 3.7% of all patients undergoing surgery and 18.5% of patients undergoing MVR. Mean age at time of first intervention was 37.8±14.4 years. Mean age in the group of patients without history of surgery was 20.6±17.5 years. Right ventricular function was evaluated using tricuspid annular plane systolic excursion (TAPSE) by echocardiographic assessment at baseline (defined as most recent exam before surgery, or first available exam in patients without history of surgery), and at last available follow-up (defined as last available exam after surgery, or last available exam prior to subsequent surgery). Mean follow-up (FU) was 7.2±7.1 years.

Results

Patients that underwent surgery with cardioplegic arrest did not experience a significant decrease in RV function over time (mean TAPSE at baseline 22.3±4.7 mm, mean difference −4.0±6.7 mm at last FU after surgery). The same was true for patients undergoing MVR with a mean TAPSE at baseline of 21.5±5.2 mm and a mean difference of −5.6±8.05 mm at last available FU (p=0.664). Freedom from impaired RV function (defined as TAPSE ≤15mm) at 5-, 10- and 15-years FU was 78%, 77%, 73%, respectively. Freedom from severe TR was 100% up to 15 years, and freedom from TVR at 5-, 10- and 15-years FU was 96%. Actuarial survival of all patients at 5-, 10- and 15-years FU was 95.6%, 94.5%, and 91.8%, respectively.

Conclusions

Current data suggests that right-sided heart lesions in MFS patients are rare. RV function remains stable over time despite (multiple) cardiac interventions. Furthermore, the need for TVR is low, independently of whether MVR was performed or not.

Funding Acknowledgement

Type of funding sources: None.

Early-experience with a novel suture device for sternal closure in pediatric cardiac surgery

BACKGROUND

Sternal closure by absorbable suture material is an established method for chest closure in pediatric cardiac surgery. However, the formation of granuloma around knotted suture material is frequently observed and has potential for prolonged wound healing and infection, particularly in newborns and infants. This retrospective study analyses the suitability and reliability of a novel absorbable, self-locking, multi-anchor knotless suture with antibacterial technology for sternal closure in pediatric cardiac surgery.

METHODS

The applied material (STRATAFIX^TMSymmetric PDS Plus, Ethicon) presents a poly-dioxanon PDS suture with a self-locking, multi anchor design, which enables a sternal closure in a continuous knotless suture technique. All children undergoing knotless closure after standard median sternotomy were examined for the occurrence of sternal wound infection or sternal instability by applying the screening criteria of the Centers for Disease Control and Prevention at hospital discharge, at 30 and 60 days.

RESULTS

In 130 cases, the new knotless sternal closure was used. Patients` mean age was 19.0±31.9 months (range: 0 to 142 months), mean bodyweight 7.8±6.6 kg (range: 2.4 to 35 kg). Delayed sternal closure occurred in 23 cases with a mean closure time after 2.9±2.6 days. One superficial incisional sternal site infection but no cases of deep sternal site infection or sternal instability were observed.

CONCLUSIONS

The application of the absorbable, knotless suture technique provides excellent results regarding the rate of sternal wound infection and improved healing after median sternotomy in pediatric patients.

Many steps can be taken to enhance recovery after thoracic surgery

Our letter to the editor comments on issues raised in the May 14, 2020, article by Budacan et al. addressing the development of enhanced recovery after thoracic surgery. In the United Kingdom and Ireland, a nationwide survey identified issues. Here, we expand on the authors’ findings.

Providing safe perioperative care in cardiac surgery during the COVID-19 pandemic

The coronavirus disease 2019 (COVID-19) pandemic has potentiated the need for implementation of strict safety measures in the medical care of surgical patients - and especially in cardiac surgery patients, who are at a higher risk of COVID-19-associated morbidity and mortality. Such measures not only require minimization of patients' exposure to COVID-19 but also careful balancing of the risks of postponing nonemergent surgical procedures and providing appropriate and timely surgical care. We provide an overview of current evidence for preoperative strategies used in cardiac surgery patients, including risk stratification, telemedicine, logistical challenges during inpatient care, appropriate screening capacity, and decision-making on when to safely operate on COVID-19 patients. Further, we focus on perioperative measures such as safe operating room management and address the dilemma over when to perform cardiovascular surgical procedures in patients at risk.

Estimating cardiac output based on gas exchange during veno-arterial extracorporeal membrane oxygenation in a simulation study using paediatric oxygenators

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) therapy is a rescue strategy for severe cardiopulmonary failure. The estimation of cardiac output during VA-ECMO is challenging. A lung circuit (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙_Lung) and an ECMO circuit (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙_ECMO) with oxygenators for CO₂ removal (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.CO₂) and O₂ uptake (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.O₂) simulated the setting of VA-ECMO with varying ventilation/perfusion (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V./\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙) ratios and shunt. A metabolic chamber with a CO₂/N₂ blend simulated \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.CO₂ and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.O₂. \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙_Lung was estimated with a modified Fick principle: \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙_Lung = \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙_ECMO × (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V. CO₂ or \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.O_2Lung)/(\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.CO₂ or \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.O_2ECMO). A normalization procedure corrected \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.CO₂ values for a \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V./\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙ of 1. Method agreement was evaluated by Bland–Altman analysis. Calculated \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙_Lung using gaseous \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.CO₂ and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.O₂ correlated well with measured \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙_Lung with a bias of 103 ml/min [− 268 to 185] ml/min; Limits of Agreement: − 306 ml/min [− 241 to − 877 ml/min] to 512 ml/min [447 to 610 ml/min], r² 0.85 [0.79–0.88]). Blood measurements of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.CO₂ showed an increased bias (− 260 ml/min [− 1503 to 982] ml/min), clinically not applicable. Shunt and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V./\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙ mismatch decreased the agreement of methods significantly. This in-vitro simulation shows that \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.CO₂ and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.O₂ in steady-state conditions allow for clinically applicable calculations of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙_Lung during VA-ECMO therapy.

Resolution of Strain Abnormalities During Extracorporeal Rewarming From Accidental Hypothermic Cardiac Arrest Following Avalanche Burial

A hypothermic avalanche victim underwent, during extracorporeal warming from asystolic arrest, 3-dimensional transesophageal echocardiography. At 33°C core temperature, left ventricular ejection fraction had recovered, whereas myocardial strain still demonstrated significant dysfunction until 36°C. Deformation analysis seems more sensitive than global assessment during myocardial recovery from hypothermic cardiac arrest. (Level of Difficulty: Intermediate.)

History, development and clinical perspectives of sutureless and rapid deployment surgical aortic valve replacement

Degenerative aortic stenosis is the most frequent valvular heart disease in industrialized countries. Conservative treatment may beneficially influence symptoms but is never successful. Surgical aortic valve replacement (SAVR) was the only recognized treatment option to provide substantially prolonged survival until 2008. Operative mortality of isolated SAVR has been reported as low as 0.5% to 1% in experienced institutions, while long-term survival is close to that observed in a control healthy population of similar age. A multitude of studies have demonstrated the beneficial effects of SAVR with regard to improvement in quality of life and physical performance in the majority of symptomatic patients. In the last decade, transcatheter aortic valve implantation (TAVI) has emerged as an equal treatment modality, first in patients with high surgical risk and more recently in patients with intermediate and low surgical risk. Paravalvular regurgitation and the higher rate of pacemaker implantation remain points of consideration. Additionally, the long-term durability of TAVI devices and occurrence of stroke late after TAVI require additional analyses. Sutureless (SU-SAVR) and rapid deployment valve (R-SAVR) were designed to simplify and accelerate a conventional or less invasive surgical procedure while allowing complete excision of the calcified native valve. From 3 different implants tested more than 10 to 15 years ago, only two are available on the market today: the Perceval^® valve from Liva Nova and the Intuity^® sutureless prosthesis from Edwards Lifesciences. There has been extensive experience with these two devices in previous years and the results obtained are comparable to those observed following the use of conventional implants. The sutureless devices may be of particular interest for more complex and combined surgical procedures. This review summarizes the sutureless (SU-SAVR) and rapid deployment valve technologies and presents a clinical outlook for the patient population managed with these devices.