The ratio of cytochrome c oxidase subunit 4 isoform 4I1 and 4I2 mRNA is changed in permanent atrial fibrillation

AIMS

The conditions of hypoxia are suggested to induce permanent atrial fibrillation (AF). The regulation of COX4I2 and COX4I1 depends on oxygen availability in tissues. A role of COX4I2 in the myocardium of AF patients is supposed for pathogenesis of AF and subsequent alterations in the electron transfer chain (ETC) under hypoxia.

METHODS AND RESULTS

In vitro, influence of hypoxia on HeLa 53 cells was studied and elevated parts of COX 4I2 were confirmed. Myocardial biopsies were taken ex vivo from the patients' Right Atria with SR (n = 31) and AF (n = 11), respectively. RT- PCR for mRNA expresson, mitochondrial respiration by polarography and the protein content of cytochrome c oxidase (CytOx) subunit 4I1 and CytOx subunit 4I2 by ELISA were studied. Clinical data were correlated to the findings of gene expressions in parallel. Patients with permanent AF had a change in isoform 4I2/4I1 expression along with a decrease of isoform COX 4I1 expression. The 4I2/4I1 ratio of mRNA expression was increased from 0.630 to 1.058 in comparison. However, the protein content of CytOx subunit 4 was much lower in the AF group, whereas the respiration/units enzyme activity in both groups remained the same.

CONCLUSIONS

This study describes a possible molecular correlate for the development of AF. Due to the known functional significance of COX 4I2, mitochondrial dysfunction can be assumed as a part of the pathogenesis of AF.

Combined Minimally Invasive Mitral Valve Surgery and Percutaneous Coronary Intervention: A Hybrid Concept for Patients with Mitral Valve and Coronary Pathologies

We evaluated the feasibility of hybrid percutaneous coronary intervention (PCI) and minimally invasive mitral valve surgery (MIMVS) in patients with concomitant coronary and mitral disease. Of 534 patients who underwent MIMVS at our institution between 2012 and 2018, those with combined mitral and single vessel coronary pathologies who underwent MIMVS and PCI were included. Patients were excluded if they had endocarditis or required emergency procedures. Preprocedural, procedural, and postprocedural data were retrospectively analyzed. In total, 10 patients (median age, 75 years; 7 males) with a median ejection fraction (EF) of 60% were included. Nine patients underwent PCI before and one after MIMVS. The success rate was 100% in both procedures. There were no postoperative myocardial infarctions or strokes. Two patients developed delirium and one required re-thoracotomy for bleeding. The median stay in intensive care and the hospital was 3 and 8 days, respectively. The 30-day survival rate was 100%. A hybrid PCI and MIMVS approach is feasible in patients with mitral valve and single vessel coronary disease. In combined pathologies, the revascularization strategy should be evaluated independent from the mitral valve pathology in the presence of MIMVS expertise. Extension of this recommendation to multivessel disease should be evaluated in future studies.

Interventional Treatment of Recurrent Ventricular Septal Defect Planed by 3D-Printed Reconstruction of the Heart

We report a complex case of a 53-year-old male patient with recurrent ischemic ventricular septal defect that had been occluded by a surgical patch. Treatment was accomplished utilizing a 3-dimensional-printed model for preprocedural planning. In the future, printing of 3-dimensional models could offer new therapeutic strategies on an individual level. (Level of Difficulty: Intermediate.).

Preoperative optimization of cardiac valve patients' expectations: Study protocol of the randomized controlled ValvEx-trial

Introduction

Complete recovery after surgery depends on psychological factors such as preoperative information, expectations, and surgery-associated anxiety. Prior studies have shown that even a short preoperative psychological intervention aiming at optimized expectations (EXPECT) can improve postoperative outcomes in coronary artery bypass patients. However, this intervention may benefit only a small subgroup of heart surgery patients since implementing preoperative psychological interventions into the daily clinical routine is difficult due to the additional time and appointments. It is unclear whether the EXPECT intervention can be shortened and whether heart valve patients would also benefit from interventions that optimize patients' expectations. The multicenter ValvEx trial aims (i) to adapt an effective preoperative psychological intervention (EXPECT) to make it brief enough to be easily integrated into the preoperative routine of heart valve patients and (ii) to examine if the adapted preoperative psychological intervention improves the subjectively perceived illness-related disability (PDI) up to 3 months after surgery.

Materials and analysis

In two German university hospitals, N = 88 heart valve patients who undergo heart surgery are randomized into two groups [standard of care (SOC) vs. standard of care plus interventional expectation manipulation (SOC and EXPECT)] after baseline assessment. Patients in the EXPECT group additionally to standard of care participate in the preoperative psychological intervention (30-40 min), focusing on optimizing expectations and have two booster-telephone calls (4 and 8 weeks after the surgery, approx. 15 min). Both groups have assessments again on the evening before the surgery, 4 to 6 days, and 3 months after the surgery.

Discussion

The trial demonstrates excellent feasibility in the clinical routine and a high interest by the patients.

Ethics and dissemination

The Ethics Committees of the Department of Medicine of the Philipps University of Marburg and the Department of Medicine of the University of Giessen approved the study protocol. Study results will be published in peer-reviewed journals and presented at congresses.

Clinical trial registration

ClinicalTrials.gov, identifier NCT04502121.

Influence of cardioplegic solution on incidence of delirium after CABG surgery: Use of Calafiore blood cardioplegia versus HTK - Bretschneider - solution in a single-center retrospective analysis from 2017 to 2021

BACKGROUND

Purpose of the present study is an evaluation of postoperative incidence for delirium after coronary artery bypass surgery (CABG). Study addressed whether application of Histidine-Tryptophan-Ketoglutarate (HTK) solution (Bretschneider) or blood cardioplegia (Calafiore) is associated with increased of postoperative delirium cases.

MATERIALS AND METHODS

In a retrospective, single center evaluation a total number of 273 patients were enrolled in the study from January 2017 to October 2021. There were 124 patients assigned to the Calafiore group blood cardioplegic solution (BCC) and 149 patients were included in the Bretschneider group (HTK). The primary endpoint was the postoperative delirium rate in its frequency of occurrence. Definition of the dilirium status was performed using the Confusion Assessment Method in the Intensive Care Unit (CAM-ICU) score during the first three postoperative days. Secondary endpoints were the time intervals of intensive care duration of stay, mechanical ventilation, total extracorporeal circulation, ischemia and reperfusion. Serum levels of the electrolytes Sodium, Potassium, ionized Calcium, and Chloride were monitored.

RESULTS

Although no significant difference in delirium status between the groups were noticed, on third postoperative day, delirium rate dependent on cardioplegia solution used (HTK 12.0%; BCC 3.0%; p = .024) and duration of intensive care stay differed (HTK 4.5 vs. BCC 3.0 days; p = .001). Although Ischemic time (HTK 73.0 vs. BCC 83.0 min; p < .001) and reperfusion time (HTK 35.0 vs. Calafiore 24.0 min; p < .001) were extended in the BCC group less cases of delirium were diagnosed. Serum sodium levels after HTK cardioplegic infusion were decreased (HTK 129.68 vs. BCC 138.96 mmol/l; p < .001). The significant difference persists up to the hundredth extracorporeal circulation circuit min (p = .005).

CONCLUSION

The present data suggest an impact of the cardioplegic solution used upon postoperative delirium rates. Optimization of cardiac arrest protocols is needed. Present data encourage further prospective studies regarding the impact of cardioplegic solutions on electrolyte imbalance for postoperative delirium rates in CABG surgery.

Empfehlungen der S3-Leitlinie (AWMF) „Einsatz der extrakorporalen Zirkulation (ECLS/ECMO) bei Herz- und Kreislaufversagen“

In den vergangenen Jahren hat der Einsatz mechanischer Unterstützungssysteme für Patienten mit Herz- und Kreislaufversagen kontinuierlich zugenommen, sodass in Deutschland mittlerweile jährlich etwa 3000 ECLS-/ECMO-Systeme implantiert werden. Vor dem Hintergrund bislang fehlender umfassender Leitlinien bestand ein dringlicher Bedarf an der Formulierung evidenzbasierter Empfehlungen zu den zentralen Aspekten der ECLS-/ECMO-Therapie. Im Juli 2015 wurde daher die Erstellung einer S3-Leitlinie durch die Deutsche Gesellschaft für Thorax-, Herz- und Gefäßchirurgie (DGTHG) bei der zuständigen Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften e. V. (AWMF) angemeldet. In einem strukturierten Konsensusprozess mit Einbindung von Experten aus Deutschland, Österreich und der Schweiz, delegiert aus 11 AWMF-Fachgesellschaften, 5 weiteren Fachgesellschaften sowie der Patientenvertretung, entstand unter Federführung der DGTHG die Leitlinie „Einsatz der extrakorporalen Zirkulation (ECLS/ECMO) bei Herz- und Kreislaufversagen“, die im Februar 2021 publiziert wurde. Die Leitlinie fokussiert auf klinische Aspekte der Initiierung, Fortführung, Entwöhnung und Nachsorge und adressiert hierbei auch strukturelle und ökonomische Fragestellungen. Dieser Artikel präsentiert eine Übersicht zu der Methodik und den konsentierten Empfehlungen.

Prediction of stroke reconvalescence after coronary bypass surgery indicated by CT scan parameters

BACKGROUND

Stroke in the postoperative time course after heart surgery remains a serious risk. Cranial computer tomography (CCT) is the first line option to detect severe intracranial damage. However, only few data are available to predict neurological outcome. Using visual rating scales (VRSs), this study addresses reliability and effectivity to indicate neurological status and likelyhood of improvement.

METHODS

In a single-center retrospective evaluation, 3719 patients underwent coronary bypass surgery. Because of a delayed recovery phase and neurologic deficits after cardiac surgery 109 patients had a cranial CT scan in the early postoperative period. The incidence of clinically relevant findings within the imaging was rated by an experienced neuroradiologist using two VRS, that is, the age-related white matter changes (ARWMCs) and the Mendes-Ribeiro visual rating scale (MRVRS). Both are computer-assisted measurement schemes to detect stroke-related intracranial damage. Follow-up was investigated with regard to clinical outcome and patient-related risk profiles.

RESULTS

Of 109 patients with postoperative cranial CT scans due to prolonged recovery phases or proven neurological damage 44.5% had one cerebral defect in CCT imaging scans only. The others showed multiple defects. During hospital stay, 92.3% experienced neurological improvement exposing reduced ARWMC, while 7.1% had no improvement and correlating high scores. Of both scales, the ARWMC-VRS demonstrated superior accuracy and discrimination. The preoperative ejection fraction (EF), arteriosclerotic degeneration of carotid arteries, and reduced glomerular filtration rate were found to have a high correlation (r = 0.0005) with the latter group. In-hospital mortality of this cohort was 8.18%.

CONCLUSION

Both the ARWMC and MRVRS were found to be appropriate. They reliably discriminate the groups of stroke patients after coronary artery bypass grafting (CABG)  in the analysis of CCT images. When applied at the onset of neurological symptoms both scales are able to predict neurological reconvalescence upon hospital dismission. The ARWMC scale appeared superior as it demonstrated better accuracy and discrimination. The use of both VRS in patients with suspected stroke after CABG surgery can give insightful information toward a progression of neurological dysfunction or postoperative improvement.

Role of matrix metalloproteinases in mitral valve regurgitation: Association between the of MMP-1, MMP-9, TIMP-1, and TIMP-2 expression, degree of mitral valve insufficiency, and pathologic etiology

BACKGROUND

The pathogenesis of mitral valve insufficiency is not yet fully understood. Several studies stressed the role of matrix metalloproteinases (MMPs) in the emergence of valvular pathologies. The primary objective of the present study is to analyze the role of selected MMPs and their inhibitors in mitral valve insufficiency.

PATIENTS AND METHODS

Eighty patients (33 female/47 male, mean age 67 years) underwent cardiopulmonary bypass surgery for mitral valve reconstruction between 2007 and 2015. All patients suffered from mitral insufficiency (MI) Stages iii and iv. When tissue resection was acquired specimens were taken immediately frozen and used for histological examination. Expression of MMP-1, MMP-9, tissue inhibitor of metalloproteinase (TIMP)-1, and TIMP-2 was examined immunohistochemically and distribution was analyzed in regard to preoperative clinical, echocardiographic, and histopathological findings.

RESULTS

A clear correlation between the MMP expression and the MI degree of severity could be shown. The expression of MMPs proved to be high in relation to mild insufficiencies and relatively weak in the case of severe ones. Additionally, the etiology of the MI was considered in the analysis and a significant difference in the expression of MMPs between the mitral valves with endocarditis and the ones featuring a degenerative disease could be shown. Within the group of valves with degenerative diseases, no significant difference could be established between the subgroups (myxoid and sclerosed valves).

CONCLUSION

The increased expression of MMPs and their inhibitors in mild insufficiencies could prove that the molecular changes in the valve precede the macroscopical and thus the echocardiographically diagnosable changes. Hence, new options for early diagnosis and therapy of MIs should be examined in further studies, respectively. Herein, the correlation of the MMP blood levels with MMP tissue expression should be addressed for surgical therapeutical decisions.

Risk factors for postoperative delirium after cardiac surgical procedures with cardioplegic arrest

OBJECTIVES

The pathophysiology of delirium after cardiac surgery is complex. The present study aims to determine perioperative risk factors and construct a scoring system for postoperative delirium based on the type of surgery.

METHODS

Three hundred patients undergoing coronary artery bypass grafting (CABG; n = 150) or valve and/or aortic surgery ± CABG (n = 150) were retrospectively evaluated.

RESULTS

The incidence of delirium (32%) was similar in subgroups (28.7% and 33.33%, P = 0.384). Delirium patients were older [71.3 (standard deviation: 8.5) vs 66.6 (standard deviation: 9.5), P < 0.001; 70.0 (standard deviation: 9.6) vs 62.5 (standard deviation: 12.6), P < 0.001] and required more packed red blood cell units [2.1 (standard deviation: 2.1) vs 4.2 (standard deviation: 4.0), P < 0.001; 2.4 (standard deviation: 3.3) vs 5.4 (standard deviation: 5.9), P < 0.001] and fresh frozen plasma units [6.1 (standard deviation: 2.9) vs. 8.0 (standard deviation: 4.2), P < 0.001; 6.3 (standard deviation: 3.4) vs 10.8 (standard deviation: 7.2), P < 0.001] in CABG and valve/aortic subgroups, respectively. Delirium was associated with longer operation time [298.3 (standard deviation: 98.4) vs 250.6 (standard deviation: 67.8) min, P < 0.001], cardiopulmonary bypass (CPB) time [171.5 (standard deviation: 54.9) vs 140.98 (standard deviation: 45.8) min, P < 0.001] and cardiac arrest time [112 (standard deviation: 35.9) vs 91.9 (standard deviation: 28.6), P < 0.001] only in the valve/aortic group (versus non-delirium). Multivariate regression analysis identified an association between delirium and age [odds ratio: 1.056 (95% confidence interval: 1.002-1.113), P = 0.041], CPB time [odds ratio: 1.1014 (95% confidence interval: 1.004-1.025), P = 0.007], fresh frozen plasma transfusion [odds ratio: 1.127 (95% confidence interval: 1.006-1.262), P = 0.039] and atrial fibrillation [odds ratio: 4.801 (95% confidence interval: 1.844-12.502), P < 0.001] after valve/aortic surgery (area under the curve 0.835, P < 0.001) and between delirium and age [odds ratio: 1.089 (95% confidence interval: 1.023-1.160), P = 0.007] and ventilation time [odds ratio: 1.068 (95% confidence interval: 1.026-1.113), P = 0.001] after isolated CABG (area under the curve 0.798, P < 0.001). The cross-validation of the results by k-fold logistic regression revealed for the entire patient cohort an overall average accuracy of the prediction model of 0.764, with a false-positive rate of 0.052 and a false-negative rate of 0.18.

CONCLUSIONS

Age, CPB time, ventilation, transfusion and atrial fibrillation are differently associated with delirium depending on the operative characteristics. Optimization of intraoperative parameters and use of risk calculators may enable early institution of pharmacotherapy and improve overall outcome after cardiac surgery.

Urinary TIMP-2 and IGFBP-7 protein levels as early predictors of acute kidney injury after cardiac surgery

BACKGROUND

Acute kidney injury (AKI) is a frequent complication associated with on-pump cardiac surgery. Early recognition may alter their prognosis. Therefore, the urinary concentrations of TIMP-2 (tissue inhibitor of metalloproteinases-2) and IGFBP7 (insulin-like growth factor-binding protein) as predictors for AKI were studied.

METHODS

Repetitive blood and urine samples were collected consecutively from 50 patients. Demographic, intra-, and postoperative data were recorded prospectively. To calculate the production of the TIMP-2 and IGFBP-7 protein concentrations, urinary samples were taken preoperatively, intraoperatively at 30 and 60 min after aortic clamping and at 0, 6, 12, and 24 h after admission to the intensive care unit (ICU).

RESULTS

AKI occurred in 14 patients (28%), all of them at Kidney Disease: Improving Global Outcomes stage 1. Predictive value for [TIMP-2] × [IGFBP7] was shown at 0 and 24 h after admission to ICU. At 0 h, the sensitivity was 84.6% and the specificity 55.6% for an ideal calculated cutoff at 0.07. After 24 h, the ideal cutoff amounted to 0.35 with a sensitivity of 53.8% and a specificity of 88.2%. The receiver operating characteristic curves demonstrated areas under the curve of 0.725 and 0.718. The suggested cutoffs of 0.3 and 2.0 could not be confirmed. The serum creatinine was reached to the peak median within 48 h after admission to ICU.

CONCLUSION

Postoperative risk assessment for the development of AKI can be established by [ TIMP - 2 ] × [ IGFBP 7 ] . Previously suggested cutoff values could not be confirmed. A correlation with urinary dilution parameters may enable the identification of more universal cutoffs.

Video-assisted minimal access surgery for complicated mitral valve endocarditis, tricuspid valve insufficiency and progressive coronary disease after previous CABG - in the time of COVID-19: a case report

BACKGROUND

The timing for heart surgery following cerebral embolization after cardiac valve vegetation is vital to postoperative recovery being uneventful, additionally Covid-19 may negatively affect the outcome. Minimally invasive methods and upgraded surgical instruments maximize the benefits of surgery also in complex cardiac revision cases with substantial perioperative risk.

CASE PRESENTATION

A 68 y.o. patient, 10 years after previous sternotomy for OPCAB was referred to cardiac surgery on the 10th postoperative day after neurosurgical intervention for intracerebral bleeding with suspected mitral valve endocarditis. Mitral valve vegetation, tricuspid valve insufficiency and coronary stenosis were diagnosed and treated by minimally invasive revision cardiac surgery on the 14th postoperative day after neurosurgery.

CONCLUSION

The present clinical case demonstrates for the first time that the minimally invasive approach via right anterior mini-thoracotomy can be safely used for concomitant complex mitral valve reconstruction, tricuspid valve repair and aorto-coronary bypass surgery, even as a revision procedure in the presence of florid endocarditis after recent neurosurgical intervention. The Covid-19 pandemic and prophylactic patient isolation slow down the efficacy of pulmonary weaning and mobilisation and prolong the need for ICU treatment, without adversely affecting long-term outcome.

Allegra Transcatheter Heart Valve inside a Degenerated Sutureless Aortic Bioprosthesis

Transcatheter aortic valve-in-valve implantation (VIV) is increasingly being used to successfully treat degenerated surgical aortic valve bioprostheses (SAVs). The new self-expanding transcatheter heart valve Allegra, from New Valve Technology with its special implantation mechanism, has proven its safety and feasibility for patients with degenerated SAVs, but it has never been used in the latest-generation sutureless SAV. To the best of our knowledge, this is the first description of the successful VIV of the Allegra prosthesis into a degenerated sutureless SAV, and the procedure yielded an excellent postinterventional hemodynamic results.

Mechanical circulatory support for early surgical repair of postinfarction ventricular septal defect with cardiogenic shock

Postinfarction ventricular septal defect (pVSD) due to acute myocardial infarction complicated by cardiogenic shock (CS) is associated with high mortality. The aim of this study was to determine the outcome of primary surgical repair of pVSD in patients with CS and examine whether it is influenced by the use of mechanical circulatory support (MCS) devices. Between October 1994 and April 2016, primary surgical repair of pVSD complicated by CS was performed in 53 patients. Thirty-six (68%) were implanted pre-operatively with an intra-aortic balloon pump (IABP), 4 (8%) with extracorporeal life support (ECLS), and 13 (24%) received no MCS device. Prospectively collected demographic and perioperative data were analyzed retrospectively. All-cause, 30-day mortality rates were analyzed and multivariate analysis was performed to differentiate independent risk factors. No pre-operatively implanted MCS device was able to improve 30-day survival, whereas pre-operatively implanted ECLS tended to have a positive effect (P = .106). The post-operative need for a MCS device or escalation of MCS invasiveness (IABP upgrade to ECLS) was associated with a higher 30-day mortality (P = .001) compared with patients without any MCS device or those with pre-operatively implanted MCS devices. An independent risk factor for 30-day mortality was the interval between acute myocardial infarction and surgery <7 days (OR 5.895, CI 1.615-21.515; P = .007). Pre-operative implantation of ECLS for CS tends to improve the outcome of early primary surgical pVSD repair. The need for a post-operative MCS device is associated with a worse 30-day survival after early primary surgical pVSD repair.

Temporal Trends in Predictors of Early and Late Mortality After Emergency Coronary Artery Bypass Grafting for Cardiogenic Shock Complicating Acute Myocardial Infarction

BACKGROUND

Cardiogenic shock after acute myocardial infarction is an indication for emergent coronary artery bypass grafting in patients not amenable to percutaneous coronary intervention. Our study aimed to evaluate and identify risk factors for early and long-term outcomes in such patients.

METHODS

A total of 508 patients who underwent coronary artery bypass grafting for cardiogenic shock complicating acute myocardial infarction between January 2000 and June 2014 were divided into 3 time cohorts: 2000 to 2004 (n=204), 2005 to 2009 (n=166), and 2010 to 2014 (n=138). Predictors of in-hospital mortality for each time cohort and long-term mortality for all patients were identified by logistic and Cox regression analyses, respectively.

RESULTS

Mean age was 68.3±9.8 years. Of the 508 patients, 78.5% had 3-vessel and 47.1% had left main disease. Left ventricular function <30% was observed in 44.1% of patients, with 30.4%, 37.9%, 52.9%, and 3.1% requiring preoperative resuscitation, ventilation, intra-aortic balloon pump, and extracorporeal membrane oxygenation support, respectively. Overall in-hospital mortality was 33.7%; declined from 42.2% to 30.7% to 24.6%, respectively, for the 3 time cohorts (P=0.02); and was independently predicted by serum lactate >4 mmol/L (odds ratio [OR], 4.78; 95% confidence interval, 2.88-7.95; P<0.0001), ST-segment-elevation myocardial infarction (OR, 2.10; 95% confidence interval, 1.36-3.26; P=0.001), age >75 years (OR, 2.01; 95% confidence interval, 1.06-3.85; P=0.03), and left ventricular ejection fraction <30% (OR, 1.83; 95% confidence interval, 1.15-2.91; P=0.01). Cumulative survival was 42.6±2.0% and 33.4±2.0% at 5 and 10 years, respectively, and correspondingly improved to 64.3±3.0% and 49.8±3.0% in hospital survivors. Serum lactate >4 mmol/L (OR, 2.2; P<0.0001), incremental age (OR, 1.05; P<0.0001), New York Heart Association class IV (OR, 1.33; P=0.02), diabetes mellitus (OR, 1.39; P=0.005), and preoperative inotropic (OR, 2.61; P=0.001) and extracorporeal membrane oxygenation (OR, 1.68; P=0.05) support predicted late mortality.

CONCLUSIONS

Emergency coronary artery bypass grafting in patients with acute myocardial infarction complicated by cardiogenic shock is associated with a high in-hospital mortality, which showed a significant decline with time. Hospital survivors have good long-term outcomes, which demonstrate the beneficial effect of surgical revascularization. Preoperative serum lactate >4 mmol/L is a strong predictor of both early and late mortality.

Treatment of Coronary Artery Disease: Randomized Trials on Myocardial Revascularization and Complete Arterial Bypass Grafting

Friedrich Wilhelm Mohr from the very beginning of his career as a cardiac surgeon was involved in the refinements of coronary artery bypass grafting (CABG). At the Leipzig Heart Center, his spirit of early adapting to new technologies inspired the entire team and led to a matchless scientific atmosphere to find solutions to improve almost all fields of cardiac surgery, including CABG. In combination with a tremendous number of patients with indications for isolated coronary artery bypass Prof. Mohr as the surgical principle investigator and the Leipzig Heart Center were able to include patients in the Synergy between PCI [percutaneous coronary intervention] with Taxus and Cardiac Surgery (SYNTAX) trial, the first randomized trials comparing CABG and PCIs using the drug-eluting stents. Final SYNTAX results after 5 years gave direction and scientific evidence for contemporary European revascularization guidelines. These guidelines recommend PCI as an alternative first-line treatment option in patients with coronary three-vessel disease and left main stenosis having low coronary complexity based on the angiographic SYNTAX score. However, the study demonstrated the significant superiority of CABG over PCI in all other patients, especially in these with complex three-vessel disease. The specific characteristic of the SYNTAX study is that the distinguished results were confirmed by several post-SYNTAX comparative randomized trials on coronary revascularization including left main disease and clinical registries even when contemporary drug-eluting stent designs were used. When performing CABG the question of the best second graft remains unclear. While several mono-institutional reports and large meta-analyses demonstrated clear superiority in terms of long-term survival when using bilateral mammary versus single mammary revascularization, this benefit could not be confirmed in randomized trials after 5 years.

The JUPITER registry: 1-year results of transapical aortic valve implantation using a second-generation transcatheter heart valve in patients with aortic stenosis

OBJECTIVES

Transcatheter aortic valve replacement (TAVR) is an established therapy for patients with aortic stenosis (AS) at high surgical risk. The JenaValve™ is a second-generation, self-expanding transcatheter heart valve (THV), implanted through transapical access (TA). During stent deployment, a specific 'clipping-mechanism' engages native aortic valve cusps for fixation. We present 1-year outcomes of the JUPITER registry, a post-market registry of the JenaValve for TA-TAVR.

METHODS

The JUPITER registry is a prospective, multicentre, uncontrolled and observational European study to evaluate the long-term safety and effectiveness of the Conformité Européenne-marked JenaValve THV. A total of 180 patients with AS were enrolled between 2012 and 2014. End-points were adjudicated in accordance with the valve academic research consortium document no. 1 definitions.

RESULTS

The mean age was 80.4 ± 5.9 years and the mean logistic European system for cardiac operative risk evaluation I 21.2 ± 14.7%. The procedure was successful in 95.0% (171/180), implantation of a second THV (valve-in-valve) was performed in 2.2% (4/180) and conversion to surgical aortic valve replacement (SAVR) was necessary in 2.8% (5/180). No annular rupture or coronary ostia obstruction occurred. Two patients required SAVR after the day of index procedure (1.1%). All-cause mortality at 30 days was 11.1% (20/180), being cardiovascular in 7.2% (13/180). A major stroke occurred in 1.1% (2/180) at 30 days, no additional major strokes were observed during 1 year. All-cause mortality after 30 days was 13.1% (21/160) and combined efficacy at 1 year was 80.8% (122/151). At 1-year follow-up, no patient presented with more than moderate paravalvular leakage, while 2 patients (3.2%) showed moderate, 12 (19.0%) mild and 49 (82.4%) trace/none paravalvular regurgitation.

CONCLUSIONS

In a high-risk cohort of patients undergoing TA-TAVR for AS, the use of the JenaValve THV is safe and effective. In patients at higher risk for coronary ostia obstruction, annular rupture or with limited aortic valve calcification, the JenaValve might be preferable for implantation due to its clipping-mechanism engaging native aortic valve cusps for fixation with reduced radial forces of the self-expanding stent.

Risk factors for mortality after pericardiectomy for chronic constrictive pericarditis in a large single-centre cohort

OBJECTIVES

Constrictive pericarditis (CP) is an uncommon disease with multiple causes and unclear clinical outcomes. To date, few publications have clearly defined risk factors of poor outcomes after surgery for CP. We performed a retrospective analysis of almost 100 patients undergoing surgical treatment for CP at a single institution in order to identify risk factors for perioperative and long-term mortality.

METHODS

A total of 97 consecutive patients (67.0% male) undergoing surgery for CP at our institution from 1995 to 2012 were included in the study. CP was diagnosed either preoperatively by cardiac catheterization and appropriate imaging or during surgery. Preoperative and intraoperative risk factors for 30-day and late mortality were analysed using stepwise multivariate logistic and Cox regression analyses. Median follow-up was 1.23 ± 3.96 years (mean 3.08 ± 3.96 years).

RESULTS

The mean patient age was 60.0 ± 12.5 years and the underlying aetiology was idiopathic (50.5%), prior cardiac surgery (15.5%), prior mediastinal radiation (9.3%), and miscellaneous (24.7%). All patients underwent either radical (55.2%) or partial (44.8%) pericardiectomy. Concomitant procedures were performed in 54 (55.7%) patients. The total procedure time was 197.0 ± 105.0 min. Cardiopulmonary bypass (CPB) was used in 62 patients with a corresponding CPB time of 124.8 ± 68.4 min. In those patients who underwent CPB, cardioplegic arrest was performed in 53.2% of patients with a mean cross-clamp time of 74.9 ± 41.9 min. Overall 30-day, 1-year and 5-year survival rates were 81.4, 66.5 and 51.6%, respectively, without significant differences according to the underlying aetiology. Multivariate analysis revealed patients with reduced left ventricular ejection fraction (LVEF) [P = 0.01, odds ratio (OR) 3.6] and preoperative right ventricular dilatation (P = 0.04, OR 3.5) to be at significant risk of early mortality. Long-term mortality was independently predicted by the presence of coronary artery disease (CAD) [P < 0.001, hazard ratio (HR) 6.44], chronic obstructive pulmonary disease (P = 0.001, HR 4.21) and preoperative renal insufficiency (P = 0.012, HR 1.8). Concomitant tricuspid valve repair (TVR) appeared to provide protective effect on the long-term survival (P = 0.07).

CONCLUSIONS

Surgery for CP is associated with a significant risk based on the poor preoperative patient status. Whenever justified, partial over radical pericardiectomy should be preferred and TVR should be indicated liberally. Reduced LVEF and right ventricular dilatation were independent predictors for early mortality, whereas CAD, chronic obstructive pulmonary disease and renal insufficiency were risk factors for late mortality. Thus, an optimal timing for surgery on CP remains crucial to avoid secondary morbidity with an even worse natural prognosis.

Intra-Aortic Balloon Pump Malposition Reduces Visceral Artery Perfusion in an Acute Animal Model

Visceral artery perfusion can be potentially affected by intra-aortic balloon pump (IABP) catheters. We utilized an animal model to quantify the acute impact of a low balloon position on mesenteric artery perfusion. In six pigs (78 ± 7 kg), a 30-cc IABP was placed in the descending aorta in a transfemoral procedure. The celiac artery (CA) and the cranial mesenteric artery (CMA) were surgically dissected. Transit time blood flow was measured for (i) baseline, (ii) 1:1 augmentation with the balloon proximal to the visceral arteries, and (iii) 1:1 augmentation with the balloon covering the visceral arteries. Blood flow in the CMA and CA was reduced by 17 and 24%, respectively, when the balloon compromised visceral arteries compared with a position above the visceral arteries (flow in mL/min: CMA: (i) 1281 ± 512, (ii) 1389 ± 287, (iii) 1064 ± 276, P < 0.05 for 3 vs. 1 and 3 vs. 2; CA: (i) 885 ± 370, (ii) 819 ± 297, (iii) 673 ± 315; P < 0.05 for 3 vs. 1). The covering of visceral arteries by an IABP balloon causes a significant reduction of visceral artery perfusion; thus, the positioning of this device during implantation is critical for obtaining a satisfactory outcome.

Not all porcelain is the same: classification of circular aortic calcifications (porcelain aorta) according to the impact on therapeutic approach

Severe aortic calcification, also known as "porcelain aorta," has a major impact on patient outcome. Its presence also influences the choice of procedure depending on where it is located. However, to date there is no clear definition on how this term should be employed, being often used as an exclusion criteria for conventional surgery where aortic clamping and/or cannulation is required.We here suggest a classification of the "porcelain aorta" regarding its location and how it influences particular therapeutic options. Therefore, making more clear what procedures would represent an increased risk for the patient and which are more suitable when discussed in a "Heart Team."Type I implies localization of a circumferential calcification in the ascending aorta. Type IA represents the calcified aorta with no possibility of clamping and Type IB represents the calcified aorta with possible clamping. Type II addresses the calcification of the descending aorta including or not the aortic arch.

Experience with anatomically orientated devices for transapical aortic valve implantation

Transcatheter aortic valve implantation (TAVI) is a new technology, which is rapidly growing to a routine procedure amenable for patients with symptomatic aortic valve stenosis and higher than average risk for conventional aortic valve surgery. The crucial disadvantage of TAVI remains the not well foreseeable risk of more than trivial degree of paravalvular leakage and a high rate of atrioventricular block and consecutive pacemaker implantation. In addition, current implantation techniques do not allow controlling the rotation of first-generation devices that might be beneficial regarding optimal physiological valve performance, optimal coronary flow and avoidance of placement of covered commissures in front of the coronary ostia. These shortcomings had pushed the development of second-generation self-expandable nitinol-based devices for subcoronary implantation that aim a reduction of paravalvular leak and AV-block by anatomical orientated positioning into the aortic root. This review focuses on the description of three different TAVI concepts, which are presently under early clinical evaluation, or have recently received commercial approval, using the transapical approach.

Review of a 13-year single-center experience with minimally invasive direct coronary artery bypass as the primary surgical treatment of coronary artery disease

BACKGROUND AND AIM OF THE STUDY

In this study, we review our experience with 1768 minimally invasive direct coronary artery bypass (MIDCAB) operations. The focus is on long-term outcome with more than 10 years of follow-up.

METHODS

All patients undergoing standard MIDCAB between 1996 and 2009 were included. For all 1768 patients, pre-, intra-, and postoperative data could be completed. Long-term follow-up information about health status, major adverse cardiac and cerebrovascular events (MACCE), and freedom from angina was collected annually via questionnaire or personal contact. Five-year follow-up is available for 1313 patients, and 10-year-follow-up is available for 748 patients. A multivariate Cox regression analysis was performed to determine risk factors for long-term outcome.

RESULTS

Mean age was 63.4 ± 10.8 years, mean ejection fraction was 60.0% ± 14.2%, and perioperative mortality risk calculated by logistic EuroSCORE was 3.8 ± 6.2%. In 31 patients (1.75%) intraoperative conversion to sternotomy was necessary. Early postoperative mortality was 0.8% (15 patients); 0.4% (7 patients) had a perioperative stroke. Seven hundred twelve patients received routine postoperative angiogram, showing 95.5% early graft patency. Short-term target vessel reintervention was needed in 59 patients (3.3%) (11 percutaneous transluminal coronary angioplasty (PTCA)/stent, 48 re-operation). Kaplan-Meyer analysis revealed a 5-year survival rate of 88.3% (95% confidence interval [CI], 86.6% to 89.9%) and a 10-year-survival rate of 76.6% (95% CI, 73.5% to 78.7%). The freedom from MACCE and angina after 5 and 10 years was 85.3% (95% CI, 83.5% to 87.1%) and 70.9% (95% CI, 68.1% to 73.7%), respectively.

CONCLUSIONS

MIDCAB is a safe operation with low postoperative mortality and morbidity. With excellent short-term and long-term results, it is a very good alternative compared to both percutaneous coronary intervention (PCI) and conventional surgery.

Selective cerebral perfusion using moderate flow in complex cardiac surgery provides sufficient neuroprotection. Are children young adults?

OBJECTIVE

Selective cerebral perfusion (SCP) is commonly applied during the correction of complex congenital cardiac defects. In this study, we assessed the impact of different flow levels of SCP on potential brain ischaemia.

METHODS

Fifteen piglets (7-10 kg, age 3-4 weeks) received SCP via the right common carotid artery during cardiopulmonary bypass at 25°C for 90 min. Regular brain perfusion (1 ml/g brain weight/min), moderate hypoperfusion (0.5 ml/g/min) and extensive hypoperfusion (0.25 ml/g/min) were evaluated. Clinical parameters and tissue oxygenation index (TOI) were registered online until 3 h of reperfusion. Hematoxylin and eosin (HE) staining and immunohistological analyses for apoptosis inducing factor (AIF) and nitrotyrosine (NO-Tyr) were performed on sections of the hippocampus.

RESULTS

Intracerebral pressure remained stable throughout the study. Haemodynamic parameters, blood gas and lactate measurements were stable until the end of the study. Extensive hypoperfusion led to a moderate reduction of TOI. NO-Tyr immuno-positive cells were 15.7% at regular cerebral perfusion, 23.9% at moderate hypoperfusion (P = n.s.) and 46.1% at extensive hypoperfusion (P < 0.05). AIF immuno-positive nuclei were present in 8.3% of the hippocampus cells after regular perfusion, in 10.8% after moderate hypoperfusion (P = n.s.) and in 17.9% after extensive hypoperfusion (P < 0.05).

CONCLUSIONS

SCP using a moderate SCP flow regime demonstrates comparable results to normal brain perfusion while after extensive hypoperfusion significant morphological brain injury could be found. Thus moderate, but not extensive, hypoperfusion might have the potential to prevent perfusion-related cerebral oedema and an increasing risk of brain injury.

Conventional aortic valve replacement in transcatheter aortic valve implantation candidates: a 5-year experience

BACKGROUND

Patient selection for transcatheter aortic valve implantation (TAVI) remains highly controversial. Some screened patients subsequently undergo conventional aortic valve replacement (AVR) because they are unsuitable TAVI candidates. This study examined the indications and outcomes for these patients, thereby determining the efficacy of the screening process.

METHODS

Between January 2006 and December 2010, 79 consecutive patients (49% men), aged older than 75 years with high surgical risk, were screened for TAVI, but subsequently underwent conventional AVR through a partial or complete sternotomy. The indications, demographics, and outcomes of this cohort were studied.

RESULTS

Mean age was 80.4±3.6 years. Mean left ventricular ejection fraction was 0.55±0.16, and the mean logistic European System for Cardiac Operative Risk Evaluation was 13%±7%. Of the 79 patients, 6 (7.6%) had prior cardiac surgical procedures. Indications for TAVI denial after patient evaluations were a large annulus in 31 (39%), acceptable risk profile for AVR in 24 (30%), need for urgent operation in 11 (14%), and concomitant cardiovascular pathology in 5 (6%). Mean cross-clamp time was 55±14 minutes, and cardiopulmonary bypass time was 81±21 minutes. Concomitant procedures included a Maze in 12 patients (15%). Postoperative morbidity included permanent stroke in 2 (2.5%), respiratory failure in 9 (11%), and pacemaker implantation in 2 (2.5%). Hospital mortality was 1.3% (1 of 79). Cumulative survival at 6, 12, and 36 months was 88.5%, 87.1% and 72.7%, respectively.

CONCLUSIONS

Our existing patient evaluation process accurately defines an acceptable risk cohort for conventional AVR. The late mortality rate reflects the advanced age and comorbidities of this cohort. The data suggest that overzealous widening of TAVI inclusion criteria may be inappropriate.

Aortic annulus sizing: echocardiographic versus computed tomography derived measurements in comparison with direct surgical sizing

OBJECTIVES

The precise sizing of the aortic annulus is crucial in order to select the most appropriate valve size for transcatheter aortic valve implantation (TAVI). Owing to the closed heart situation in TAVI, sizing has to be performed based on preoperative imaging when compared with direct sizing during conventional procedures. The aim of the study was to evaluate valve sizing performed either by CT-scan or by echocardiography by comparing these imaging-based measurements with direct intraoperative sizing.

METHODS

Prior to the standard conventional aortic valve replacement, 26 patients underwent cardiac CT-scan and echocardiographic examination. Maximal annular diameter was measured by echocardiography at end-diastole and end-systole, including the leaflet calcifications. The CT-scan maximal, minimal and mean diameters were measured as well as the 'effective' diameter (CT(eff)). CT(eff) represents the diameter of a circle with the exact same area as the measured area of the annular circumference reconstructed from the CT-data set. Direct intraoperative diameters were measured after decalcification using metric sizers.

RESULTS

CT(eff) and end-systolic echocardiographic diameters showed best agreement with intraoperative direct sizing (intraop) in the Bland-Altman analysis [mean difference for transoesophageal echocardiography (TEE) vs intraop 0.5 mm (limits of agreement -2.5-3.5); mean difference for transthoracic echocardiography (TTE) vs intraop 0.38 mm (limits of agreement -3.28-4.03) and CT(eff) vs intraop -0.56 (limits of agreement -3.16-2.05)]. In patients with an oval-shaped annulus, CT(eff) demonstrated the best agreement with intraop [mean difference -0.32 (limits of agreement -2.29 to 1.66)].

CONCLUSIONS

Both the 'effective' CT diameter and end-systolic TEE values are the most reliable approaches for preoperative aortic annulus sizing. In patients with a pronounced oval-shaped annulus, the 'effective' CT diameter seems to be the method of choice. Therefore, aortic annulus measurement using 'effective' CT diameters should be included into current recommendations for TAVI sizing.

Transapical aortic valve implantation off-pump in patients with impaired left ventricular function

BACKGROUND

Patients with impaired left ventricular ejection fraction (LVEF) and severe aortic stenosis have a higher perioperative risk for aortic valve replacement. Transapical aortic valve implantation (TA-AVI) allows for off-pump valve implantation, which might be beneficial in the subgroup of patients with impaired LVEF.

METHODS

All patients with LVEF≤40% who underwent TA-AVI for severe aortic stenosis and who fulfilled at least 1-year follow-up formed the study group. Results were compared to TA-AVI patients with preserved LVEF treated during the same time period.

RESULTS

Thirty-nine patients with LVEF≤40% were identified, mean LVEF was 32.5±7.1%. Logistic EuroSCORE and STS-score were 43.6%±18.5% and 15.3%±9.3%, respectively. Concomitant coronary artery disease was present in 59% with 23.1% having had previous bypass surgery and 17.9% having had a history of prior myocardial infarction. Two patients required cardiopulmonary-bypass support due to intraoperative complications, and another 2 patients required cardiopulmonary-bypass for reperfusion. Median procedure time was 75 minutes (interquartile range, 65-90 minutes). LVEF at discharge increased significantly to a mean of 41.5%±10%, and at 1-year follow-up to 53.9%±13% (both p<0.0001). The proportion of patients in New York Heart Association class III-IV decreased from 92.3% to 15.0% at 1-year follow-up (p<0.001). There was neither a statistically significant difference in in-hospital mortality nor in long-term survival up to 4 years, in comparison to patients with preserved LVEF.

CONCLUSIONS

Transapical aortic valve implantation is a promising approach, allowing for off-pump treatment of elderly, high-risk patients with impaired LVEF requiring aortic valve replacement. Short-term and long-term outcomes are respectable, and an improvement in postoperative LVEF and New York Heart Association class can be anticipated.

A second prosthesis as a procedural rescue option in trans-apical aortic valve implantation

OBJECTIVE

Trans-apical aortic valve implantation (TA-AVI) using the Edwards SAPIEN™ prosthesis has evolved to a routine procedure for selected high-risk elderly patients. In rare cases, misplacement of the SAPIEN™ valve (too low a position), dysfunction of the leaflets or perforation of the interventricular septum (ventricular septal defect, VSD) occurs and requires immediate implantation of a second prosthesis within the first one. Results of this 'bailout' maneuver have not been reported yet.

METHODS

Of 305 TA-AVI procedures, 15 patients required a second prosthesis due to dysfunctional leaflets (n = 6), low position (n = 7), or VSD (n = 2). Mean age was 82.5 ± 1.3 years, mean logistic EuroSCORE (European System for Cardiac Operative Risk Evaluation) was 45.5 ± 5.4, and Society of Thoracic Surgeons (STS) Score was 13.5 ± 1.5.

RESULTS

All second SAPIEN™ valves could be implanted successfully within the first one. The second prosthesis solved leaflet dysfunction, sealed the VSD (lower position of the second prosthesis), or corrected the initial misplacement (higher position of the second prosthesis) in all patients. Within 30 days, four patients died (low cardiac output n = 3, all with preoperative ejection fraction (EF) <35%; intestinal ischemia n = 1). Intra-operative echocardiogram and angiogram revealed mild paravalvular leak in three and none/trace in 12 patients. Transvalvular gradients were low despite the implantation of the second valve (P(max)/mean 13.7 ± 4.3/6.4 ± 2.0).

CONCLUSION

Placement of a second SAPIEN™ valve is a valuable 'bailout' technique in case of VSD, dysfunctional leaflets, or too low placement of the first prosthesis. The technique leads to an excellent functional result with low transvalvular gradients. The simple, straight, tubular stent design of the SAPIEN™ prosthesis may be the ideal design for such valve-in-valve procedures.

Outcome of Coronary Artery Bypass Grafting – Strategies for Improvement

During recent years, new conceptual, technical and drug strategies have led to improved early and late outcomes after coronary artery bypass surgery. These new strategies can be divided into the following three groups: optimisation of pre-operative patient selection and indications for and timing of the operation; peri-procedural refinements, including new techniques and instruments to avoid extracorporeal circulation, reduce aortic manipulation and minimise surgical access; and improvements to post-operative care, such as fast-track protocols and long-term drug therapy. In summary, the wide range of the surgical armamentarium available today allows cardiovascular surgeons to adapt the surgical strategy to individual patients and the given clinical scenario. This article aims to describe clinical rationales for the adoption of new concepts, provide an introduction to technical details and discuss clinical study results where appropriate.

Risk of acute kidney injury after minimally invasive transapical aortic valve implantation in 270 patients

OBJECTIVE

Contrast agent is a potential risk factor for acute kidney injury (AKI). Little is known about the incidence of contrast-induced nephropathy (CIN) after trans-apical aortic valve implantation (TA-AVI) and on the impact of contrast exposure during preoperative computed tomography (CT) scan and cardiac catheterization.

METHODS

A total of 270 consecutive high-risk patients received TA-AVI for symptomatic aortic valve stenosis during a 3-year period. Different preoperative, peri-procedural, and postoperative variables were analyzed by uni- and multivariate logistic regression concerning incidence of early (<7 days) AKI and need for renal replacement therapy (RRT). Nine patients on chronic preoperative dialysis were excluded.

RESULTS

Mean age was 82 ± 5.8 years, 71% were female. LogEuroSCORE (European System for Cardiac Operative Risk Evaluation) and STS Score were 31.4 ± 15.6% and 12.1 ± 7.4%, respectively. Preoperative estimated glomerular filtration rate (eGFR) <60 ml min(-1) was present in 35.2%. CT scan and cardiac catheterization within 7 days before TA-AVI were performed in 43.7% and 20.3% of the patients and were associated with a mean contrast-agent exposition of 110 ± 21 ml for CT scans and 91 ± 65 ml for cardiac catheterization. Regarding the postoperative renal outcome, an improved or at least stable eGFR was seen in more than 50% of the patients. Intra-operative contrast-agent application was 99 ± 64 ml and correlated significantly to the development of postoperative AKI and need for RRT (p=0.013 and p=0.003). Postoperative RRT was required in 15.7%. Chronic renal insufficiency (odds ratio (OR)=6.8, p=0.025) and number of blood transfusions (OR=8.8, p=0.009) were independent risk factors for RRT. Postoperative AKI occurred in 16.1% and intra-operative contrast-agent burden >99 ml (OR=2.3, p=0.038), new thrombocytopenia (OR=4.4, p=0.005) and pathological leucocyte count (OR=2.8, p=0.009) were independent risk factors for this event. Early (within 1-7 days before TA-AVI) preoperative CT and cardiac catheterization did not significantly increase incidence of RRT or AKI. Short-term and long-term survival was explicitly lower in the AKI and in the RRT groups (p<0.001 each).

CONCLUSIONS

GFR improves after TA-AVI. Postoperative AKI and RRT depend on the amount of intra-operative contrast agent. These results strongly support the need for intra-operative tools to reduce contrast-agent exposition during TA-AVI.

Coronary artery disease: a new manifestation in Dubowitz syndrome

We report here a case of coronary artery disease in a patient with Dubowitz syndrome. A 19-year-old man suffered from recurrent angina after an anterior wall myocardial infarction. Coronary angiogram demonstrated severe stenoses of the left main and obtuse marginal vessels, as well as occlusion of the left anterior descending artery. The patient was successfully treated with coronary artery bypass graft surgery.