Alexandro Hoyer

Acute type A aortic dissection: characteristics and outcomes comparing patients with bicuspid versus tricuspid aortic valve

OBJECTIVES The aim of this study is to investigate the clinical characteristics and postoperative outcome of patients with a bicuspid aortic valve (BAV) suffering acute dissection in comparison with their tricuspid peers. METHODS Between 1995 and 2011, 460 consecutive patients underwent emergency repair for acute type A aortic dissection. In 379 patients without connective tissue disease, the aortic valve morphology could clearly be specified (91.6% tricuspid and 8.4% bicuspid). RESULTS At the time of dissection, patients with a bicuspid valve were younger (46.7 ± 13 vs 61.6 ± 12 years, P < 0.001) with the entry tear more often located in the root compared with those with a tricuspid valve (bicuspid: 31.3% vs tricuspid: 6.3%, P < 0.001). Consequently, surgical repair warranted root replacement in 93.8% of bicuspid vs 28.8% of tricuspid valve patients (P < 0.001). The leading pathology was medial necrosis/degeneration in bicuspid and atherosclerosis in tricuspid patients (P = 0.166). Hospital mortality was 20.3% and not significantly different between the two valve morphologies, even despite the younger age of bicuspid patients: 28.1% among bicuspids vs 19.6% among tricuspids (P = 0.255). Survival after discharge was 63.3% at 10 years for all patients. BAV patients had a significantly better survival with 100% at 10 years compared with 60.2% in tricuspid valve patients (P = 0.011). Mean follow-up among survivors was comparable for bicuspid and tricuspid patients (3.7 and 4.1 years, respectively). CONCLUSIONS Patients with BAV have a distinctive dissection pattern with the entry tear frequently located in the aortic root and-despite their younger age-are subject to substantial hospital mortality. For bicuspid patients suffering from dissection, composite root replacement yields an excellent outcome equal to an age- and gender-matched normal population.

Longevity After Aortic Root Replacement Is the Mechanically Valved Conduit Really the Gold Standard for Quinquagenarians

Background— The choice of the best conduit for root/ascending disease and its impact on longevity remain controversial in quinquagenarians. Methods and Results— A total of 205 patients (men=155) between 50 and 60 years (mean, 55.7±2.9 years) received either a stentless porcine xenoroot (n=78) or a mechanically valved composite prosthesis (n=127) between February 1998 and July 2011. Of these, 166 patients underwent root replacement for aneurysmal disease (porcine: 39% [n=65]; mechanical: 61% [n=101]; P=0.5), 25 for acute type A aortic dissection (porcine: 32% [n=8]; mechanical: 68% [n=17]; P=0.51), and 14 for endocarditis/iatrogenic injury involving the aortic root (6.4% [n=5] versus 7.1% [n=9]; P=1.0). The predominant aortic valve pathology was stenosis in 19% (n=38), regurgitation in 50% (n=102), combined valvular dysfunction in 26% (n=54), and normal aortic valve function in 5% (n=11). Concomitant procedures included coronary artery bypass grafting (13%), mitral valve repair (7%), and partial/complete arch replacement (12%/4%), with no significant differences between porcine and mechanical root replacement. Overall hospital mortality was 7.3%, with no difference between the 2 types of valve prostheses (7.7% for porcine and 7.1% for mechanical root replacement; P=1.0). Follow-up averaged 5.4±3.7 years (1096 patient-years) and was 100% complete. Freedom from aorta-related reoperation at 12 years was not statistically different between the groups (porcine: 94.9% versus mechanical: 96.1%; P=0.73). Survival was equivalent between both groups, with a 5-year survival of 86±3% (porcine: 88±4%; mechanical: 85±3%; P=0.96) and a 10-year survival of 76% (porcine: 80±7%; mechanical: 75±5%; P=0.84). The linearized mortality rate was 3.1%/patient-year (porcine: 2.9%/patient-year; mechanical: 3.2%/patient-year). Conclusions— In quinquagenerians, long-term survival after stentless porcine xenograft aortic root replacement is equivalent to that after a mechanical Bentall procedure. These results bring into question the predominance of mechanical composite conduits for root replacement in quinquagenerians, particularly in the current era of transcatheter valve-in-valve procedures for structural valve deterioration.

Transapical Mitral Valve Implantation for Native Mitral Valve Stenosis Using a Balloon-Expandable Prosthesis

BACKGROUND Transcatheter mitral valve implantation (TMVI) is still in its infancy and is mainly limited to valve-in-valve or valve-in-ring implantations. We present the early experience with TMVI for severe calcified native MV stenosis. METHODS Between January 2014 and June 2015, 6 of 11 patients screened (mean age, 77.4 ± 6.3 years; 66% men) with severe native mitral valve (MV) stenosis (mean gradient [Pmean], 11.1 ± 2.1 mm Hg; mean effective orifice area [EOA], 0.9 ± 0.12 cm2) underwent transcatheter MV replacement at our institution as a bailout procedure. Conventional surgical procedures were denied in all patients because of severe annular calcification and extensive comorbidities (mean logistic EuroScore, 31.4% ± 8.3%). The Edwards SAPIEN 3 (29 mm) (Edwards Lifesciences, Irvine, CA) was used in all cases. Procedural access was transapical in 5 cases and concomitant to aortic valve replacement through the left atrium through a sternotomy in 1 case. RESULTS Initial implantation was successful in 100% of the cases. Because of early migration, 1 patient needed a valve-in-valve procedure. Postoperative echocardiography showed no residual mitral regurgitation in 4 cases (66%) and mild regurgitation in 2 cases (34%). Mean gradients were reduced to 4.2 ± 0.6 mm Hg (mean EOA, 2.8 ± 0.4 cm2). No patient had a stroke during hospitalization, and 30-day mortality was seen in 1 patient (17%) resulting from pneumonia. CONCLUSIONS TMV implantation using the SAPIEN 3 aortic prosthesis in patients with heavy annular calcification is feasible and represents a reasonable bailout option for inoperable patients. However, several limitations need to be considered in this special patient population.

Preoperative Predictors and Outcome of Triple Valve Surgery in 487 Consecutive Patients

Background Triple valve surgery (TVS) is associated with an elevated risk for operative mortality and thus remains a surgical challenge. We report our experience and results of TVS procedures, especially with respect to identification of preoperative risk factors, to improve patient selection. Methods Between December 1994 and January 2013, 487 consecutive patients (240 male, 247 female) underwent TVS at the Heart Center Leipzig, University of Leipzig. The data were prospectively collected and retrospectively analyzed. Univariate and multivariable regression analyses were performed to identify risk factors. Results The 30‐day mortality was 16.1% and the long‐term survival at 1 year and 5 years was 71.8% and 54.6%, respectively. Multivariable logistic regression analysis identified previous myocardial infarction to be the only significant predictor for early mortality. Age, New York Heart Association functional class IV, previous myocardial infarction, dialysis, and liver dysfunction were identified as preoperative predictors for late mortality. Furthermore, an increase of operative risk, given for each year, was observed during the study period. In contrast, 30‐day mortality decreased during the observation time. Conclusion TVS is associated with a high surgical risk. Long‐term survival is decreased, but acceptable for these high‐risk patients. The series demonstrates that increasing surgical risk, age, and comorbidities are the future challenges in TVS.

Good 5-Year Durability of Transapical Beating Heart Off-Pump Mitral Valve Repair With Neochordae

BACKGROUND Transapical, beating heart, off-pump implantation of neochordae for repair of mitral valve (MV) prolapse is of increasing interest. The aim of this study was to evaluate long term results for MV repair using the NeoChord system (NeoChord, St. Louis Park, MN). METHODS Six patients underwent treatment for severe primary mitral regurgitation (MR) with the NeoChord DS1000 system as part of the initial device safety and feasibility Transapical Artificial Chordae Tendinae (TACT) trial at our institution (University of Leipzig-Heart Center, Leipzig, Germany). The primary pathology in all patients was isolated posterior leaflet prolapse of the P2 or P3 segment, or both. RESULTS Successful repair resulting in no or trace MR was achieved in 5 of 6 patients by implantation of three neochordae under transesophageal echocardiographic guidance and normal left ventricular loading conditions. One patient underwent intraoperative conversion to an open MV replacement as a result of leaflet injury. The early postoperative course was uneventful in all remaining patients. Two patients had to undergo reoperation for recurrent MR at 3 and 16 months postoperatively. The remaining 3 patients were followed up for a period of 5 years. These patients were free of cardiac symptoms, and transthoracic examination showed trace or mild to moderate MR at 1-, 2-, and 5-year follow-up. A trend toward reverse remodeling of the left ventricle with no increase in mitral annular dilatation over 5 years was observed. CONCLUSIONS In select patients, MV repair using the NeoChord system results in very good long-term results without recurrent prolapse, MR, or annular dilatation.

Evaluation of conventional and frozen elephant trunk techniques on spinal cord blood flow in an animal model

OBJECTIVES The treatment of patients with extensive thoracic aortic disease involving the arch and descending aorta is often performed using the frozen elephant trunk technique (FET). Spinal cord blood flow (SCBF) in cervical, thoracic and lumbar sections prior, during and after aortic arch surgery were compared in conventional elephant trunk (cET) and FET technique in a pig model. METHODS German Landrace pigs (75‐85 kg) underwent aortic arch surgery using the FET (n = 8) or cET (n = 8) techniques. The E‐vita Open hybrid stent graft was applied in all FET animals. Regional SCBF was measured 4 times: (i) before cardiopulmonary bypass, (ii) after 1 h, (iii) after 3 h, and (iv) after 6 h of reperfusion using fluorescence microspheres. Spinal cord segments were examined histopathologically and by immunohistochemistry. RESULTS SCBF in FET decreased significantly from 0.13 ± 0.03 to 0.05 ± 0.02 ml/min/g after 1 h (P = 0.047). While at 3 h of reperfusion, SCBF increased and was comparable to baseline (0.09 ± 0.01 ml/min/g), beyond this time SCBF decreased again (0.05 ± 0.02 ml/min/g). A similar trend was found for SCBF in the cET group (baseline: 0.16 ± 0.04 ml/min/g, 1 h reperfusion: 0.02 ± 0.01 ml/min/g, 3 h reperfusion: 0.03 ± 0.01 ml/min/g and 6 h reperfusion: 0.02 ± 0.01 ml/min/g, P = 0.019). Cervical, thoracic and lumbar SCBF were also comparable in both groups. Histological analyses of spinal cord showed no differences in necrosis between cET and FET, while no differences were found for hypoxia‐inducible factor‐1&agr; and apoptosis‐inducing factor. In contrast, oxidative stress and caspase‐induced apoptosis were higher in cET versus FET. CONCLUSIONS The SCBF changed significantly during extensive aortic arch surgery with circulatory arrest and moderate hypothermia, but such changes were comparable between the FET and cET groups. The implantation of hybrid stent graft did not influence SCBF in thoracic and lumbar segments of the spinal cord. The immunohistological examination showed no differences between cET and FET regarding ischaemic damage and hypoxia‐induced effects in spinal cord segments.

Custodiol versus cold Calafiore for elective cardiac arrest in isolated aortic valve replacement: a propensity-matched analysis of 7263 patients

OBJECTIVES This study was designed to assess the impact of crystalloid cardioplegia (CCP) and blood cardioplegia (BCP) on short- and long-term outcome after isolated aortic valve replacement (AVR). METHODS A total of 7263 patients undergoing AVR at our institution between November 1994 and June 2015 were identified. CCP (Custodiol ® ) was used in 83% ( n  = 5998) and intermittent cold BCP in 1007 patients (14%). For 4790 patients, propensity scores were calculated from baseline data, risk factors, comorbidities and characteristics of the disease, resulting in 825 pairs. The primary outcome was operative mortality (OM). RESULTS There was no significant difference in OM between CCP and BCP cohorts [33 of 825 (4.0%) vs 35 of 825 (4.2%), P  = 0.90]. The incidence of postoperative complications was comparable between both groups. Long-term survival was also not different between CCP and BCP (log-rank test: P  = 0.9). Multiple Cox regression analysis demonstrated that mortality was significantly affected by renal function ( P  < 0.001), logistic EuroSCORE ( P  < 0.001), male sex ( P  = 0.005) and diabetes ( P  = 0.037). Patients with reduced left ventricular ejection fraction ≤30% showed improved survival when receiving BCP intraoperatively [odds ratio: 2.28 (1.12-4.63); P  = 0.03]. CONCLUSIONS CCP and BCP provide equivalent outcome after isolated AVR. However, BCP seems to be beneficial for patients with reduced left ventricular ejection fraction.