Management of acute and chronic aortic disease during the COVID-19 pandemic-Results from a web-based ad hoc platform.

BACKGROUND: To share the results of a web-based expert panel discussion focusing on the management of acute and chronic aortic disease during the coronavirus (COVID-19) pandemic. METHODS: A web-based expert panel discussion on April 18, 2020, where eight experts were invited to share their experience with COVID-19 disease touching several aspects of aortic medicine. After each talk, specific questions were asked by the online audience, and results were immediately evaluated and shared with faculty and participants. RESULTS: As of April 18, 73.3% answered that more than 200 patients have been treated at their respective settings. Sixty-four percent were reported that their hospital was well prepared for the pandemic. In 57.7%, the percentage of infected healthcare professionals was below 5% whereas 19.2% reported the percentage to be between 10% and 20%. Sixty-seven percent reported the application of extracorporeal membrane oxygenation in less than 2% of COVID-19 patients whereas 11.8% reported application in 5%-10% of COVID-19 patients. Thirty percent of participants reported the occurrence of pulmonary embolism in COVID-19 patients. Three percent reported to have seen aortic ruptures in primarily elective patients having been postponed because of the anticipated need to provide sufficient ICU capacity because of the pandemic. Nearly 70% reported a decrease in acute aortic syndrome referrals since the start of the pandemic. CONCLUSION: The current COVID-19 pandemic has-besides the stoppage of elective referrals-also led to a decrease of referrals of acute aortic syndromes in many settings. The reluctance of patients seeking medical help seems to be a major driver. The number of patients, who have been postponed due to the provisioning of ICU resources but having experienced aortic rupture in the waiting period, is still low. Further, studies are needed to learn more about the influence that the COVID-19 pandemic has on the treatment of patients with acute and chronic aortic disease.

Pulmonary artery vs. transpulmonary thermodilution for the assessment of cardiac output in mitral regurgitation: a prospective observational study.

CONTEXT: With increasing prevalence of mitral regurgitation, even noncardiac anaesthesiologists will be confronted by this disorder and will need to be familiar with the extended haemodynamic monitoring required. The assessment of cardiac output (CO) measured by transpulmonary thermodilution (COTP) has become an accepted alternative to the CO measured by thermodilution via pulmonary artery catheter (COPAC). However, the integrity of COTP in severe mitral regurgitation requires systematic evaluation. OBJECTIVE: This study was designed to test the hypothesis that transpulmonary thermodilution is compromised by severe mitral regurgitation. DESIGN: Prospective method comparison study. SETTING: Single university-affiliated hospital. PARTICIPANTS: Thirty patients with mitral regurgitation undergoing elective mitral valve repair. MAIN OUTCOME MEASURE: COTP and COPAC were determined in triplicate after induction of anaesthesia, and at the end of surgery after closure of the chest. The methods were compared using bias and precision statistics. RESULTS: Echocardiography revealed severe mitral regurgitation in most patients (n  =  27) after induction of anaesthesia. The least significant change in COTP (the minimum change in COTP required to detect a real change with a probability of 95%) was increased under the condition of mitral regurgitation (15.4  ±  10.2% after anaesthesia induction vs. 9.3  ±  5.9% after valve repair, P = 0.008), whereas it remained constant in COPAC (9.6  ±  5.4 vs. 8.5  ±  7.2%, P = 0.55). There was no significant bias between COTP and COPAC after anaesthesia induction [mean CO, 4.03 ±â€Š0.92 l  min; bias 0.12 l  min (95% confidence interval, CI, -0.073 to 0.311)], and after valve repair [mean CO 7.47  ±â€Š 1.44 l  min; bias 0.045 l  min (95% CI, -0.147 to 0.237)]. The percentage error was 28.4 and 13.6%, respectively. CONCLUSION: The results suggest that even severe mitral regurgitation has no significant impact on the accuracy of COTP. The precision of COTP was reduced under the condition of mitral regurgitation.

Results of open thoracoabdominal aortic replacement in patients unsuitable for or after endovascular repair with remaining disease components.

OBJECTIVES: Our goal was to evaluate outcomes in all-comer patients undergoing open thoracoabdominal aortic replacement either unsuitable for or after failed endovascular aortic repair. METHODS: Within a 4-year period, we analysed a consecutive series of 80 patients undergoing elective, urgent and emergency thoracoabdominal aortic replacement. Preoperative data, intraoperative data and outcomes were evaluated. Specific attention was given to technical refinements needed in patients after previous endovascular aortic repair. RESULTS: Eighty patients underwent thoracoabdominal aortic replacement: 11.3% (n = 9) had connective tissue disorders. Twenty-six patients (32.5%) had previous endovascular aortic repair and 54 (67.5%) did not have previous endovascular repair. The mean age was 64.2 ± 12 years, and 70% (n = 56) were male. The mean EuroSCORE was 7.9 ± 2.6. Urgent or emergency operations were done in 22.5% (n = 18). Overall mortality was 20% (n = 16); symptomatic spinal cord injury occurred in 5% (n = 4). We did not observe differences in survival according to the presence or absence of previous endovascular aortic repair (P = 0.524). Multivariate regression analysis revealed the amount of packed red blood cell units (P = 0.009, confidence interval 1.028-1.215, odds ratio = 1.117) as a predictor of in-hospital death. Follow-up was 100% (37.9 ± 15.8 months); freedom from aortic-related reintervention was 96.3%. CONCLUSIONS: Despite an early attrition rate, survival after open thoracoabdominal aortic replacement is excellent, and freedom from aortic-related reintervention is high. Open surgery continues to remain an essential component in the treatment armamentarium of acute and chronic thoracoabdominal aortic pathology.

Acute hemodynamic effects of right and left ventricular lead positions during the implantation of cardiac resynchronization therapy defibrillators.

BACKGROUND: To evaluate the acute hemodynamic effects of different right (RV) and left ventricular (LV) pacing sites in patients undergoing the implantation of a cardiac resynchronization therapy defibrillator (CRT-D). METHODS: Stroke volume index (SVI), assessed via pulse contour analysis, and dp/dt max, obtained in the abdominal aorta, were analyzed in 21 patients with New York Heart Association class III heart failure and left bundle branch block (mean ejection fraction of 24 ± 6%), scheduled for CRT-D implantation under general anesthesia. We compared the hemodynamic effects of RV apical (A), RV septal (B), and biventricular pacing using the worst (lowest SVI; C) and best (highest SVI; D) coronary sinus lead positions. RESULTS: Mean arterial pressure, SVI, and dp/dt max did not differ significantly between RV apical and septal pacing. Dp/dt max and SVI increased significantly during biventricular pacing (dp/dt max: B, 588 ± 160 mmHg/s; C, 651 ± 218 mmHg/s, P = 0.03 vs B; D, 690 ± 220 mmHg/s, P = 0.02 vs C; SVI: B, 33.6 ± 5.5 mL/m², C, 34.8 ± 6.1 mL/m², P = 0.08 vs B, D 36.0 ± 6.0 mL/m², P < 0.001 vs C). The best hemodynamic response was associated with lateral or inferior lead positions in 15 patients. Other LV lead positions were most effective in six patients. CONCLUSIONS: The optimal LV lead position varies significantly among patients and should be individually determined during CRT-D implantation. The impact of the RV stimulation site in patients with intraventricular conduction delay, undergoing CRT-D implantation, has to be investigated in further studies.

Evaluation of myocardial injury, the need for vasopressors and inotropic support in beating-heart aortic arch surgery.

BACKGROUND: In contrast to the standard cardioplegic cardiac arrest (CA), some centers prefer the beating-heart technique using selective normothermic myocardial perfusion (SMP) during aortic arch repair. The aim of this study was to evaluate myocardial injury and the need for inotropic and vasopressor support in patients undergoing total aortic arch replacement using SMP or CA during arch repair. METHODS: Total arch replacement was performed in 127 patients (65 years [IQR: 56-73 years] years) between March 2013 and May 2018 via the frozen elephant trunk technique. Of those, 25 patients were operated on with selective myocardial perfusion. Blood samples and catecholamine doses were evaluated. We compared the SMP group's and CA group's outcomes. RESULTS: The two groups' risk factors, underlying aortic pathologies, and surgical details were similar. The SMP group's intraoperative norepinephrine application rates were significantly lower than the CA group's (P=0.030), as were their postoperative norepinephrine application rates (norepinephrine: P=0.007). Postoperative cardiac enzymes tended to be lower in the SMP group; the difference in creatine-kinase MB reached statistical significance after 14 hours (P=0.024). Intensive care unit stay was significantly shorter in the SMP group (P=0.041), and in-hospital mortality was comparable (4% in the SMP and 11% in the CA group; P=0.46). CONCLUSIONS: By applying selective normothermic myocardial perfusion, beating-heart aortic arch surgery has the potential to reduce the need for perioperative inotropes, and it might reduce myocardial injury. This approach is a potentially useful adjunct to our armamentarium, particularly in patients with preexisting myocardial damage or in conjunction of arch repair together with other cardiac procedures.

Predicted and measured plasma propofol concentration and bispectral index during deep sedation in patients with impaired left ventricular function.

OBJECTIVE: To evaluate the ability of the Schnider pharmacokinetic model to predict plasma propofol concentration during target-controlled propofol infusion in patients with impaired left ventricular function and to investigate the predictive value of the bispectral index (BIS) to indicate deep sedation in this patient group. DESIGN: Prospective, observational study. PARTICIPANTS: Thirty-four patients (mean left ventricular ejection fraction 31% +/- 9%) undergoing the implantation of a cardioverter-defibrillator during deep sedation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Predicted and measured propofol plasma concentrations and BIS were assessed during steady-state conditions with the propofol infusion rate constant for at least 20 minutes. The plasma propofol concentration was significantly underestimated by the pharmacokinetic model used (mean percentage prediction error 37% +/- 49%). The 50% probability of deep sedation was calculated at a predicted propofol concentration of 2.09 (95% confidence interval [CI], 2.04-2.14) mug/mL and at a measured propofol concentration of 2.70 (95% CI, 2.62-2.78) mug/mL. BIS values showed a marked variability among individuals during deep sedation (5th-95th percentiles: 25-81). CONCLUSIONS: The pharmacokinetic model used markedly underestimated propofol plasma levels in the patient group studied. The large variability among patients suggests that BIS monitoring is not suitable for indicating an exact endpoint corresponding to deep sedation.

Changes in pulse pressure variability during cardiac resynchronization therapy in mechanically ventilated patients.

INTRODUCTION: The respiratory variation in pulse pressure (PP) has been established as a dynamic variable of cardiac preload which indicates fluid responsiveness in mechanically ventilated patients. The impact of acute changes in cardiac performance on respiratory fluctuations in PP has not been evaluated until now. We used cardiac resynchronization therapy as a model to assess the acute effects of changes in left ventricular performance on respiratory PP variability without the need of pharmacological intervention. METHODS: In 19 patients undergoing the implantation of a biventricular pacing/defibrillator device under general anesthesia, dynamic blood pressure regulation was assessed during right ventricular and biventricular pacing in the frequency domain (power spectral analysis) and in the time domain (PP variation: difference between the maximal and minimal PP values, normalized by the mean value). RESULTS: PP increased slightly during biventricular pacing but without statistical significance (right ventricular pacing, 33 +/- 10 mm Hg; biventricular pacing, 35 +/- 11 mm Hg). Respiratory PP fluctuations increased significantly (logarithmically transformed PP variability -1.27 +/- 1.74 ln mm Hg2 versus -0.66 +/- 1.48 ln mm Hg2; p < 0.01); the geometric mean of respiratory PP variability increased 1.8-fold during cardiac resynchronization. PP variation, assessed in the time domain and expressed as a percentage, showed comparable changes, increasing from 5.3% (3.1%; 12.3%) during right ventricular pacing to 6.9% (4.7%; 16.4%) during biventricular pacing (median [25th percentile; 75th percentile]; p < 0.01). CONCLUSION: Changes in cardiac performance have a significant impact on respiratory hemodynamic fluctuations in ventilated patients. This influence should be taken into consideration when interpreting PP variation.

Unilateral pulmonary oedema after minimally invasive cardiac surgery via right anterolateral minithoracotomy.

OBJECTIVES: To investigate the incidence of unilateral pulmonary oedema after minimally invasive cardiac surgery (MICS) requiring unilateral lung collapse has been unknown until now. METHODS: We analysed the data of 484 consecutive patients undergoing minimally invasive cardiac surgery with unilateral lung collapse between January 2008 and December 2013. The clinical regimen was changed in 2010 to a single dose of dexamethasone (approximately 1 mg/kg body weight) administered after anaesthesia induction. RESULTS: Thirty-eight patients developed a radiographically evident unilateral pulmonary oedema within 24 h after surgery. Dexamethasone significantly reduced the incidence of this event [4.0 vs 12.9%; unadjusted odds ratio (OR) 0.28, 95% confidence interval (CI) 0.14-0.58, P < 0.001]. One patient with and six patients without dexamethasone were clinically symptomatic (P = 0.001). Logistic regression analysis identified four variables significantly associated with the development of a unilateral lung oedema: dexamethasone (OR 0.28, 95% CI 0.13-0.58, P = 0.001), diabetes mellitus (OR 3.17, 95% CI 1.04-9.63, P = 0.04), the level of mean pulmonary arterial pressure (OR 1.05 per mmHg, 95% CI 1.004-1.09, P = 0.03) and transfusion of fresh frozen plasma (OR 2.31, 95% CI 1.02-5.25, P = 0.045). CONCLUSIONS: Our data revealed a 7.9% incidence of radiographically evident unilateral pulmonary oedema after MICS with intraoperative collapse of a lung. Of the total number of patients, 1.5% simultaneously developed clinical symptoms. The influence of corticosteroids, as well as the contribution of possible risk factors, needs further evaluation.

[Cardiac output determination by thermodilution and arterial pulse waveform analysis in patients undergoing aortic valve replacement].

PURPOSE: To compare the accuracy of cardiac output (CO) measurement by arterial pulse waveform analysis (CO(PW)) to thermodilution assessments in patients with aortic stenosis, a high-risk patient group who may benefit from extended hemodynamic monitoring. METHODS: In 30 patients with aortic stenosis, CO was assessed in triplicate by thermodilution via pulmonary artery catheterization (CO(PAC)), and by arterial pulse waveform analysis (CO(PW)), before and after valve replacement. The techniques were compared by assessing the repeatability coefficient of each method and by calculating the percentage error, bias, and the limits of agreement between methods. RESULTS: The repeatability coefficients of CO(PAC) and CO(PW) were 0.89 L.min(-1) and 1.04 L.min(-1) respectively after induction of anesthesia, which corresponded to 24% of CO(PAC) and 26% of CO(PW), and increased to 33% of CO(PAC) and 32% of CO(PW) immediately after extracorporeal circulation. A systematic error between methods was not observed. The limits of agreement were bias +/- 1.42 L.min(-1) after anesthesia induction, corresponding to a 36% percentage error. The scattering of differences between methods increased markedly after termination of extracorporeal circulation (percentage error 56%). CONCLUSION: The repeatability of CO(PAC), as well as of CO(PW), is reduced in patients with aortic stenosis. The repeatability of both methods, as well as the agreement between methods, decreased markedly immediately after termination of cardiopulmonary bypass.