M. Schlömicher

Nonthyroidal Illness Syndrome in Cardiac Illness Involves Elevated Concentrations of 3,5-Diiodothyronine and Correlates with Atrial Remodeling

Background: Although hyperthyroidism predisposes to atrial fibrillation, previous trials have suggested decreased triiodothyronine (T3) concentrations to be associated with postoperative atrial fibrillation (POAF). Therapy with thyroid hormones (TH), however, did not reduce the risk of POAF. This study reevaluates the relation between thyroid hormone status, atrial electromechanical function and POAF. Methods: Thirty-nine patients with sinus rhythm and no history of atrial fibrillation or thyroid disease undergoing cardiac surgery were prospectively enrolled. Serum concentrations of thyrotropin, free (F) and total (T) thyroxine (T4) and T3, reverse (r)T3, 3-iodothyronamine (3-T1AM) and 3,5-diiodothyronine (3,5-T2) were measured preoperatively, complemented by evaluation of echocardiographic and electrophysiological parameters of cardiac function. Holter-ECG and telemetry were used to screen for POAF for 10 days following cardiac surgery. Results: Seven of 17 patients who developed POAF demonstrated nonthyroidal illness syndrome (NTIS; defined as low T3 and/or low T4 syndrome), compared to 2 of 22 (p < 0.05) patients who maintained sinus rhythm. In patients with POAF, serum FT3 concentrations were significantly decreased, but still within their reference ranges. 3,5-T2 concentrations directly correlated with rT3 concentrations and inversely correlated with FT3 concentrations. Furthermore, 3,5-T2 concentrations were significantly elevated in patients with NTIS and in subjects who eventually developed POAF. In multivariable logistic regression FT3, 3,5-T2, total atrial conduction time, left atrial volume index and Fas ligand were independent predictors of POAF. Conclusion: This study confirms reduced FT3 concentrations in patients with POAF and is the first to report on elevated 3,5-T2 concentrations in cardiac NTIS. The pathogenesis of NTIS therefore seems to involve more differentiated allostatic mechanisms.

Risk factors for acute kidney injury following TA-TAVI or minimally invasive aortic valve replacement: which procedure is less kidney damaging in elderly patients?

BACKGROUND Acute kidney injury (AKI) represents a major complication following aortic valve replacement in elderly patients. The aim of this study was to determine possible risk factors for AKI and to find the ideal strategy, minimally invasive valve replacement (MIS-AVR) or transapical valve implantation (TA-TAVI), regarding the postoperative renal outcome. METHODS A total of 133 patients (age ≥ 75 years, 67 male) with severe aortic stenosis were included over 2 years: 42% were treated with MIS-AVR, 58% underwent TA-TAVI procedure. AKI was considered as a postprocedural 1.5× increase in creatinine or an increase of > 0.3 mg/dL/48 hours. Group differences were tested with chi-square or t-test. AKI risk assumption was analyzed in multiple multivariate logistic regression models. RESULTS EuroSCORE II-related risk assumption was 8.7 ± 6.9 for TA-TAVI and 4.5 ± 5.7 for MIS-AVR (p < 0.001). The overall 30-day survival rate was 93%. Fifty-eight patients developed a risk for AKI and 13 developed a manifest renal injury/failure. Logistic regression analysis revealed a higher AKI risk for TA-TAVI (odds ratio, OR = 2.58; 95% confidence interval, CI = 1.18, 5.63; p = 0.017). EuroSCORE II (OR = 0.98; 95% CI = 0.92, 1.04; p = 0.433); preoperative creatinine (OR = 1.78; 95% CI = 0.67, 4.77; p = 0.249) and estimated glomerular filtration rate (OR = 1.00; 95% CI = 0.97, 1.02; p = 0.655) had no impact on AKI. A regression model adjusting for the variables age, gender, body mass index (BMI), diabetes, and procedure type revealed a higher AKI rate for male gender (OR = 2.41; 95% CI = 1.13, 5.11; p =  0.022). Operation time and radio-contrast media volume had no influence on the AKI-occurrence. There was no correlation between AKI and early mortality. CONCLUSION A higher risk for AKI after TA-TAVI should be considered in the therapy decision, especially in elderly male patients because MIS-AVR still yields excellent results.

Simultaneous Double Valve-in-Valve TAVI Procedure for Failed Bioprostheses

A 78-year-old female patient who had undergone double valve replacement in 2010 presented in 2014 with severe New York Heart Association grade IV dyspnea. The decision was made to perform a transapical valve-in-valve transcatheter aortic valve implantation (TAVI) procedure in the mitral and aortic positions simultaneously. The postoperative course was uneventful, and the patient was extubated 6 hours after the TAVI procedure.

Annular rupture leading to fatal complications in an elderly patient with calcified aortic and mitral annulus undergoing transapical aortic valve implantation.

This case illustrates the awareness that must be taken of the high morphological risk due to the calcifications of both, the aortic and mitral annulus in elderly patients when performing transapical aortic valve implantation. In an 86-year-old, multimorbid woman (logistic EuroSCORE = 27%) with symptomatic aortic stenosis (annular diameter = 23.4 mm) and severe mitral annular calcification, the implantation of a 26-mm Edwards SAPIEN (Edwards Lifesciences, Irvine, California, United States) valve in aortic position was primary successful, with no paravalvular leakage, valve instability, or coronary malperfusion. Second, a persisting transmural bleeding led to hypovolemic shock, which could not be stabilized even after going on cardiopulmonary bypass, and the patient died in the operation room. The autopsy showed a subvalvular ventricular rupture due to a transmural perforation of the calcified fibrotic annulus during valvuloplasty.

Rapid deployment aortic valve replacement in a minimal access setting: intermediate clinical and echocardiographic outcomes†

OBJECTIVES Transcatheter procedures have overtaken conventional operations in Germany. Considering that this is a highly competitive field, a rate of 25% for minimal access aortic valve replacement seems to be disappointingly low. One way to promote minimal access techniques is through the systematic use of rapid deployment valves. METHODS A total of 143 patients underwent rapid deployment aortic valve replacement via upper right hemisternotomy between March 2012 and September 2015. All patients were followed up annually. Echocardiographic assessment of the valve was performed after 12 months. The cumulative follow-up time was 275.2 patient-years. The median follow-up time was 1.9 years. RESULTS The mean age was 76.4 ± 6.2 years, and the mean logistic EuroSCORE was 11.0 ± 4.3%. Early all-cause mortality was 2.8% (n = 4). Actuarial survival after 1 year was 91.6 ±  2.4%, and after 3 years, it was 84.4 ± 3.6%. Mean transprosthetic gradient after 12 months was 10.3 ± 3.8 mmHg. New onset of higher grade paravalvular leakage did not occur during the follow-up period. Perioperatively, higher grade paravalvular leakage (aortic insufficiency  >1+) occurred in 2 cases (1.4%) . CONCLUSIONS Rapid deployment aortic valve replacement can be performed safely in a minimal access setting with low complication rates and good haemodynamic results. Therefore, rapid deployment valves are a relevant option in minimal access surgery.

Comparison of two biological aortic valve prostheses inside patient-specific aorta model by bi-directional fluid-structure interaction

Abstract In Germany in 2016 17,085 patients received TAVI operations and 9,579 had conventional aortic valve surgery. The ‘Heart Team’ uses established scoring systems (EuroSCORE, STS, German AV Score) to evaluate operation risks and which technique to use. However, such risk grading fails to consider patient morphology and possible long-term behavior of the replacement valve chosen. Therefore, preoperative simulation of the dynamic loading on the valve leaflets after TAVR provides information vital for the selection of the appropriate aortic valve therapy - interventional versus conventional. Individual aorta used in this study was captured by MRI. Segmentation and data processing were done with Mimic In-novation Suite. The available biological aortic valves prostheses were reverse engineered to create a 3D CAD model. Simulations combined bi-directional fluid structure interaction (FSI) with a first order Ogden model of the hyperelastic behavior of aortic leaflets from bovine pericardium. Movements induced by flow and the resultant tension on the biological leaflets were computed with developed simulation model. Stress analyses of the leaflets showed behavior attributable to their particular structure. Both valves showed two stress peaks within the initial 0.3 s. Maximum stress occurred, however, at other time points. Furthermore, the initial increase in stress showed a delayed onset. The patterns of movement were also significantly different. So, at opening of the valve, the freely perfused area of the valve, the freedom of leaflet movement and symmetry at closure were different in the two valves. Simulated movement of valve leaflets corresponds well with reality. The estimated stresses clearly lie below thresholds published in the literature for bovine pericardium. It is planned to further develop the current workflow to increase stability and optimize processing time, with the intention of providing the ‘Heart Team’ with a tool for incorporating individual anatomy when selecting the aortic valves.

Rapid-Deployment Aortic Valve Replacement after Previous Mechanical Valve Implantation

Recent studies report a reproducible reduction of myocardial ischemic and cardiopulmonary bypass times along with excellent hemodynamics and low rates of paravalvular leakage for rapid-deployment valves. A 68-year-old female patient with aortic stenosis and a mechanical mitral valve which was implanted in 2006 received rapid-deployment aortic valve replacement. The procedure could be performed with a cross-clamp time of 45 minutes and a cardiopulmonary bypass time of 60 minutes. Postoperative course was uncomplicated and the patient was discharged to the referring hospital on postoperative day 8.

Rapid deployment aortic valve replacement in the setting of concomitant mitral valve procedures

The technique of rapid deployment aortic valve implantation in patients with concomitant mitral valve surgery is described and the outcome of our first 25 patients reported.

Chronic Pericardial Hematoma with Suppression of the Right Ventricle: A Rare Complication of a Coronary Artery Aneurysm

We present a case of a 67-year-old patient referred to our department with a pericardial mass lesion measuring 11 × 4 × 7.5 cm as diagnosed in computed tomography scan. The patient showed a history of progredient dyspnea. Video-assisted thoracoscopy as well as an explorative full sternotomy to resect the mass lesion had been performed at the referring hospital subsequently before admission to our department. Intermittent hemodynamic instability caused the procedure to stop and a transfer to the cardiothoracic surgery department, following which a resternotomy was performed. Inspection of the surgical site and subsequent intraoperative rapid section revealed an old organized and dense pericardial hematoma adherent to the right ventricle. The suspicion of covered coronary artery perforation led to an intraoperative coronary angiography, which revealed a large proximal coronary aneurysm of the right coronary artery and a subtotal stenosis of the circumflex branch. The hematoma could be removed with decompression of the right ventricle under cardiopulmonary bypass conditions. The further postoperative course was uncomplicated with retransfer to the referring hospital on the postoperative day 8.

8-year experience with the LABCOR bioprosthesis in the Aortic position

Objectives: Between 2004 and 2010 330 patients with a mean age of 75.8 ± 7.2 years and mean logistic EuroSCORE of 8.5% underwent AVR with the LABCOR porcine bioprosthesis in our institution. This paper presents clinical results against the background following a trend towards bovine devices through the last decade. Patients and methods: There were 159 (48.2%) female and 171 (51.8%) male patients. Preoperatively, 69 patients (21%) were in NYHA Class II, 214 (65%) in Class III and 47 (14%) in Class IV. Concomitant Bypass Surgery was performed in 130 cases. Data were obtained during a 6 month interval period through telephone interviews with patients and referring physicians. Guidelines for reporting mortality and morbidity after valvular operations were followed in these interviews. Results: 30-day mortality was 4.5% (n = 15). There was no evidence of valve failure. Survival after a mean follow-up of 5.8 years was 63%. A reoperation rate of 3.6% (n = 12) was found. Reoperation was conducted due to prosthetic endocarditis in 7 cases, due to PVL in 3 cases, due to structural valve deterioration in 1 case and 1 patient showed a ventricular-aortal discontinuity of the muscular septum. 22 patients (39.2%) were in NYHA Class I, 22 (39,%) in Class II, 11 (19.6%) in Class III and 1 patient (1.8%) in Class IV at the time of follow-up. Conclusion: In this middle follow-up term of 8 years of clinical experience in a single center, the LABCOR porcine bioprosthesis shows reliable and satisfying results in a patient group with a medium risk profile. Nevertheless, further long-term assessment and echocardiographic examination is needed.