The impact of acute kidney injury stages on the outcomes of veno-arterial extracorporeal membrane oxygenation.

BACKGROUND: Although acute kidney injury (AKI) has been established as an independent risk factor for in-hospital mortality for patients on veno-arterial (V-A) extracorporeal membranous oxygenation (ECMO), the impact of Kidney Disease Improving Global Outcomes (KDIGO) stages of AKI has yet to be elucidated as a risk factor. METHODS: We conducted a retrospective analysis of patient outcomes based on KDIGO stages of AKI at a single institution. The analysis was a cohort of 179 patients; 66 without AKI, 19 with stage 1 AKI, 18 with stage 2 AKI, and 76 with stage 3 AKI. RESULTS: Every 1-year increase in age was associated with 4% increased odds of mortality at 30 days (95% confidence interval [CI] 1.01, 1.07; p = 0.004). The presence of AKI at any stage was associated with 59% increased odds of 30-day mortality (95% CI 0.81, 3.10; p = 0.176). The presence of stage 1 AKI was associated with a 5% decreased odds of 30-day mortality (95% CI 0.32, 2.89). The presence of stage 2 AKI (odds ratio [OR] 2.29, 95% CI 0.69, 7.55; p = 0.173) and stage 3 AKI (OR 1.68, 95% CI 0.81, 3.46; p = 0.164) was associated with increased odds of 30-day mortality. CONCLUSION: Based on our single-center study, higher KDIGO stages of AKI likely have increased odds of mortality at 30 days. Larger studies are needed to confirm these findings.

Pulmonary Artery Dual-Lumen Cannulation Versus Two Cannula Percutaneous Extracorporeal Membrane Oxygenation Configuration in Right Ventricular Failure.

Refractory right ventricular failure has significant morbidity and mortality. Extracorporeal membrane oxygenation is indicated when medical interventions are deemed ineffective. However, it is still being determined if one configuration is better. We conducted a retrospective analysis of our institutional experience comparing the peripheral veno-pulmonary artery (V-PA) configuration versus the dual-lumen cannula with the tip in the pulmonary artery (C-PA). The analysis of a cohort of 24 patients (12 patients in each group). There was no difference in survival after hospital discharge (58.3% in the C-PA group compared to 41.7% in the V-PA group, p = 0.4). Among the C-PA group, there was a statistically significant shorter ICU length of stay (23.5 days [interquartile range {IQR} = 19-38.5] vs. 43 days [IQR = 30-50], p = 0.043) and duration of mechanical ventilation (7.5 days [IQR = 4.5-9.5] compared to (16.5 days [IQR = 9.5-22.5], p = 0.006) in the V-PA group. In the C-PA group, there were lower incidents of bleeding (33.33% vs. 83.33%, p =0.036) and combined ischemic events (0 vs. 41.67%, p = 0.037). In our single-center experience, the C-PA configuration might have a better outcome than the V-PA one. Further studies are needed to confirm our findings.

Post-Transplant Extracorporeal Membrane Oxygenation for Severe Primary Graft Dysfunction to Support the Use of Marginal Donor Hearts.

Severe primary graft dysfunction (PGD) is the leading cause of early postoperative mortality following orthotopic heart transplantation (OHT). Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has been used as salvage therapy. This study aimed to evaluate the outcomes in adult OHT recipients who underwent VA-ECMO for severe PGD. We retrospectively reviewed 899 adult (≥18 years) patients who underwent primary OHT at our institution between 1997 and 2017. Recipients treated with VA-ECMO (19, 2.1%) exhibited a higher incidence of previous cardiac surgery (p = .0220), chronic obstructive pulmonary disease (p = .0352), and treatment with a calcium channel blocker (p = .0018) and amiodarone (p = .0148). Cardiopulmonary bypass (p = .0410) and aortic cross-clamp times (p = .0477) were longer in the VA-ECMO cohort and they were more likely to have received postoperative transfusion (p = .0013); intra-aortic balloon pump (IABP, p < .0001), and reoperation for bleeding or tamponade (p < .0001). The 30-day, 1-year, and overall survival after transplantation of non-ECMO patients were 95.9, 88.8, and 67.4%, respectively, compared to 73.7, 57.9, and 47.4%, respectively in the ECMO cohort. Fourteen (73.7%) of the ECMO patients were weaned after a median of 7 days following OHT (range: 1-12 days). Following OHT, VA-ECMO may be a useful salvage therapy for severe PGD and can potentially support the usage of marginal donor hearts.

Extended Static Hypothermic Preservation In Cardiac Transplantation: A Case Report.

BACKGROUND: The donor shortage poses a major limitation to use of heart transplantation. Novel strategies such as use of expanded-criteria donors with prolonged ischemia times are being employed to address this need. Recent developments in static hypothermia have allowed for the safe use of cardiac allografts with prolonged ischemic times. CASE REPORT: We present the case of a 68-year-old woman with valvular cardiomyopathy refractory to medical therapy who underwent orthotopic heart transplantation with a cardiac allograft exposed to elevated ischemic times. This was achieved through use of the federally approved SherpaPak Cardiac Transport System for transportation of the allograft. This method of static hypothermic organ preservation allowed for a 330-minute total ischemic time, including 283 minutes of storage within the preservation system. The patient tolerated the procedure well and was discharged on postoperative day 10, with excellent graft function and no evidence of rejection 3 months postoperatively. CONCLUSIONS: Though traditionally ischemic times of 240 minutes or less are recommended for cardiac allografts, we demonstrate, to our knowledge, the longest reported ischemic time of 330 minutes via use of a novel method of static hypothermia for organ preservation. The recipient had an excellent outcome postoperatively, demonstrating the potential for this new organ preservation system to expand the donor pool and improve access and use of heart transplantation.

First lung and kidney multi-organ transplant following COVID-19 Infection.

As the world responds to the global crisis of the COVID-19 pandemic an increasing number of patients are experiencing increased morbidity as a result of multi-organ involvement. Of these, a small proportion will progress to end-stage lung disease, become dialysis dependent, or both. Herein, we describe the first reported case of a successful combined lung and kidney transplantation in a patient with COVID-19. Lung transplantation, isolated or combined with other organs, is feasible and should be considered for select patients impacted by this deadly disease.

Operative Technique of Donor Organ Procurement for En Bloc Heart-liver Transplantation.

Combined heart-liver transplant is an emerging option for patients with indications for heart transplantation and otherwise prohibitive hepatic dysfunction. Heart-liver transplantation is particularly relevant for patients with single ventricle physiology who often develop Fontan-associated liver disease and fibrosis. Although only performed at a limited number of centers, several approaches to combined heart-liver transplantation have been described. The en bloc technique offers several potential advantages over the traditional sequential technique. Specifically, en bloc heart-liver transplantation may allow improved hemodynamics, decreased bleeding, reduced liver allograft ischemic time, and may result in reduced rates of graft dysfunction. Here we describe our center's en bloc heart-liver procurement technique in detail, with the aim of allowing broader use and standardization of this technique.

Left ventricular remodeling after transcatheter aortic valve implantation: one-year follow-up study.

OBJECTIVE: The impact of transcatheter aortic valve implantation (TAVI) on left ventricular (LV) mass regression is not well defined. We aimed to measure LV mass regression, changes in LV volumes and dimensions, as well as mitral valve function after TAVI. METHODS: Eighty patients who underwent TAVI between 2008 and 2010 were studied. Echocardiographic findings before procedure and at 6- and 12-month follow-up were analyzed. RESULTS: Aortic valve area increased from 0.71 (0.27) cm before procedure to 1.89 (0.64) cm at 12 months (P < 0.001), which was associated with reduction in peak [80.79 (23) vs 16.9 (6.5) mm Hg, P < 0.001] and mean [47.65 (14.2) vs 8.77 (3.29) mm Hg, P < 0.001] gradients. At 1 year, there was a change in LV end-systolic volume [46.12 (36.6) to 48.96 (4.05) mL, P = 0.042] and LV mass [202.4 (92.2) to 183.6 (98.2) g, P = 0.04]. Left ventricular mass index regressed from 130.7 (28.9) to 122.1 (28.9) g/m (P = 0.01). Maximum wall thickness decreased from 1.28 (0.18) to 1.25 (0.17) cm (P < 0.001). There was no significant change in LV ejection fraction, LV end-systolic and end-diastolic diameters, as well as mitral valve regurgitation. CONCLUSIONS: Transcatheter aortic valve implantation is associated with significant regression of LV hypertrophy at 1 year. However, this regression was not associated with changes in LV systolic and diastolic functions, size, or changes in mitral valve regurgitation.

Incidence and mechanisms of cerebral ischemia after transcatheter aortic valve implantation compared with surgical aortic valve replacement.

BACKGROUND: The most likely mechanisms of neurologic injury after transcatheter aortic valve implantation (TAVI) and aortic valve replacement (AVR) are cerebral embolization and hypoperfusion. We set out to determine potential mechanisms of neurologic injury after TAVI compared with AVR. METHODS: One hundred twenty-seven consecutive high-risk patients with severe aortic stenosis (AS) who underwent TAVI (n = 85) or AVR (n = 42) were studied. Transcranial Doppler ultrasound (TCD), cerebral oximetry, diffusion-weighted magnetic resonance imaging (DW-MRI) (before, 6 days, and 3 months after procedure), and neurocognitive assessment before and at 3 months were performed. RESULTS: Neurologic injury was not significantly different between TAVI and AVR at 1 (1.1% vs 2.2%, p = 0.25) and 3 months (4.7% vs 2.2%, p = 1). At 3 months, overall cognitive score was higher in AVR compared with TAVI when adjusted for baseline score; the estimated difference between groups was 0.63 (95% confidence interval 0.87% to 1.17%; p = 0.02). Cerebral embolic load was 212 (123 to 344) during AVR and 134 (76 to 244) during TAVI (p = 0.07). Cerebral oxygen desaturation during AVR (7.56 ± 2.16) was higher compared with TAVI (5.93 ± 2.47) (p < 0.01). Ischemic lesions measured by DW-MRI occurred in 76% of TAVI and 71% of AVR patients at 6 days (p = 0.69) and 63% and 39% at 3 months (p = 0.11). No significant association was found between cerebral emboli, cerebral oxygen desaturation, brain ischemic lesions, and general cognitive score. CONCLUSIONS: At 3 months follow-up, overall cognitive score was higher in AVR compared with TAVI, adjusted for baseline score. However, there was no difference in cerebral embolic load, ischemic lesions, and oxygen desaturation.

Left lower lobe torsion following upper lobectomy-prompt recognition and treatment improve survival.

Lobar torsion is a rare but life-threatening complication after lung resection. We report a case of left lower lobe torsion in 57-year-old women after upper lobectomy for underlying lung cancer. Definitive diagnosis of lung torsion was made at exploratory thoracotomy following abnormal chest radiography and bronchoscopy on the first post-operative day. An emergency completion pneumonectomy was performed and left lower lobe was resected. The post-operative course was uncomplicated and patient was discharged home on the seventh post-operative day. Early recognition and prompt treatment of lobar torsion is essential for preventing potentially catastrophic complications including fatal gangrene of the pulmonary lobe.

What is the value of topical cooling as an adjunct to myocardial protection?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'What is the value of topical cooling as an adjunct to myocardial protection?' Using the reported search, 9 papers represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The studies included four randomized controlled trials (RCTs). Two RCTs demonstrated no cardioprotective effects of topical hypothermia as they found no statistically significant differences in myocardial markers between patients with or without topical cooling. In a randomized study of 249 patients undergoing elective cardiac surgery, phrenic nerve injury and failure of extubation occurred more frequently with the use of topical hypothermia with iced slush (P = 0.009 and P = 0.034, respectively). One retrospective analysis found that patients who received iced topical hypothermia had longer postoperative hospitalization, higher incidence of atelectasis and higher left diaphragms on chest X-ray. Another study showed increased morbidity and mortality associated with postoperative diaphragmatic dysfunction resulting from the use of iced slush topical cooling of the heart. We conclude that topical cooling is an unnecessary adjunct to myocardial protection in patients undergoing cardiac surgery. There is no evidence of any additional cardioprotective benefit. Several studies showed that the use of topical hypothermia is associated with phrenic nerve injury, leading to diaphragmatic paralysis and increased pulmonary complications. Moreover, long-term follow-up data showed often incomplete regression of the phrenic nerve paralysis. However, few randomized studies exist on the value of topical cooling as an adjunct to myocardial protection.

Which patients should be on renin-angiotensin system blockers after coronary surgery?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'which patients should be on renin-angiotensin system blockers after coronary surgery?' Using the reported search, 12 papers represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The 12 studies included 5 prospective randomized controlled trials (RCTs) and 1 meta-analysis. One RCT of 2553 stable patients post-coronary artery bypass surgery (CABG) with left ventricular (LV) ejection fraction ≤40% showed that angiotensin-converting enzyme inhibition (ACEI) therapy can and probably should be delayed beyond 7 days due to increased cardiovascular morbidity and mortality associated with immediate postoperative initiation of ACEI treatment. Another study showed that the cardioprotective benefits of ACEI following CABG are persistent with respect to an LV ejection fraction below or above 40% and whether percutaneous coronary intervention (PCI) or CABG was performed. A large multicentre international study of 4224 patients undergoing CABG looking at a composite outcome of rates of cardiac, cerebral and renal events and in-hospital mortality showed that continuous treatment with ACEI compared with no ACEI was associated with reductions of risks of non-fatal events (P = 0.009, odds ratio 0.69, 95% confidence interval 0.52-0.91). Addition of ACEI de novo following surgery was also associated with significant reduction in the risk of the composite outcome (P = 0.004) and of a cardiovascular event (P = 0.04). We conclude that angiotensin-converting enzyme inhibitor treatment plays an important role in minimizing ischaemic events after CABG even in low-risk patients. The cardioprotective benefits of these drugs are persistent at mid- and long-term follow-up, with respect to LV ejection fraction below or above 40% and whether PCI or CABG was performed. Not only continuation of angiotensin-converting enzyme inhibition early after surgery but also adding ACEI de novo postoperatively can be associated with better cardiovascular and renal outcomes.

Survival, predictive factors, and causes of mortality following transcatheter aortic valve implantation.

OBJECTIVE: Transcatheter aortic valve implantation (TAVI) is considered the standard of care for patients with severe symptomatic aortic stenosis unsuitable for surgery. However, short- and long-term mortality after TAVI are still relatively high. The aim of this study was to establish survival, predictive factors, and causes of mortality after TAVI at early and midterm follow-up. METHODS: Between December 2007 and May 2012, a total of 119 patients with symptomatic severe aortic stenosis underwent 121 TAVI procedures. The mean ± SD age was 81 ± 9 years, and 59% were men. The mean ± SD logistic European System for Cardiac Operative Risk Evaluation was 22 ± 15. Seventy-five patients (63%) were in New York Heart Association functional class III to IV. The transfemoral approach was used in 76% of the patients. One hundred ten patients (91%) had the CoreValve prosthesis, and 11 (9%) had an Edwards SAPIEN valve. Baseline characteristics, procedural complications, and outcomes were collected prospectively. Clinical outcomes were defined according to the Valve Academic Research Consortium criteria. Follow-up was completed for 100% of the patients at a median of 1.3 years (range, 0-4.5). RESULTS: The total number of deaths was 36 (30%). One-month mortality was 4.2%. Actuarial survival was 83.2%, 76.5%, and 68.2% at 1, 2, and 3 years, respectively. Acute kidney injury occurred in 12.3% of the patients, none of whom required dialysis during hospitalization. Twenty-one patients (17.6%) had new conduction abnormalities that required permanent pacemaker implantation before hospital discharge. The incidence of major vascular injury and stroke was 2.4% and 4.1%, respectively. Survival was significantly adversely affected by preprocedural left ventricular dysfunction (P = 0.04), history of atrial fibrillation (P = 0.03), prior heart block (P < 0.01), and critical preoperative state (P < 0.01). Twelve (33%) of the 36 deaths were due to bronchopneumonia. In 12 (33%) of the 36 patients who died, mortality was related to cardiac causes. When a death occurred within the first 30 days, it was mainly cardiac in nature (80%). Twelve patients (34%) died because of a variety of other reasons such as pulmonary embolism, stroke, cancer, renal failure, and sepsis. CONCLUSIONS: Preprocedural left ventricular dysfunction, atrial fibrillation, and heart block are independent predictive factors of all-cause mortality. Early mortality was mainly cardiac in origin. Most of the late deaths were caused by noncardiac reasons, with bronchopneumonia being reported as the most common cause of late mortality.

Acute kidney injury after transcatheter aortic valve implantation: incidence, risk factors, and prognostic effects.

OBJECTIVE: Acute kidney injury (AKI) is a common complication after surgical aortic valve replacement and is associated with increased mortality. Transcatheter aortic valve implantation (TAVI) is now considered the criterion standard treatment of patients with severe symptomatic aortic stenosis ineligible for surgery. The aim of this study was to establish the incidence, risk factors, and prognostic consequences of AKI after TAVI and at 1-year follow-up in a single center. METHODS: Between December 2007 and March 2011, a total of 79 patients with severe aortic stenosis who underwent 81 TAVI procedures with the Medtronic CoreValve System or the Edwards SAPIEN heart valve were included. Baseline characteristics and procedural complications were recorded. Acute kidney injury was defined according to the Valve Academic Research Consortium criteria (modified risk, injury, failure, loss, and end-stage kidney disease criteria). RESULTS: The mean age was 84 (78-87) years; 49 were men. After TAVI, 10 patients (12.3%) developed AKI, which had completely resolved in 9 patients before hospital discharge. Nine patients (10%) had mild AKI (stage 1) and only one patient (10%) experienced moderate AKI (stage 2) according to Valve Academic Research Consortium definitions. The predictive factors of AKI were diabetes (odds ratio, 6.722; P = 0.004) and preoperative creatinine level greater than 104 µmol/L (odds ratio, 1.024; P = 0.02). Thirteen patients (16.4%) died within 1 year after TAVI. Three of the nonsurvivors (3.7%) developed AKI postoperatively. Acute kidney injury was, however, not a predictive factor of 1-year mortality after TAVI. CONCLUSIONS: Acute kidney injury occurred in 12.3% of the patients after TAVI and persisted in only one patient before hospital discharge. Diabetes and preoperative creatinine level were found to be the main predictive factors of AKI after TAVI. Acute kidney injury was not associated with increased 1-year mortality.