Cardiac shockwave therapy in addition to coronary bypass surgery improves myocardial function in ischaemic heart failure: the CAST-HF trial.

BACKGROUND AND AIMS: In chronic ischaemic heart failure, revascularisation strategies control symptoms but are less effective in improving left ventricular ejection fraction (LVEF). The aim of this trial is to investigate the safety of cardiac shockwave therapy (SWT) as a novel treatment option and its efficacy in increasing cardiac function by inducing angiogenesis and regeneration in hibernating myocardium. METHODS: In this single-blind, parallel-group, sham-controlled trial (cardiac shockwave therapy for ischemic heart failure, CAST-HF; NCT03859466) patients with LVEF ≤40% requiring surgical revascularisation were enrolled. Patients were randomly assigned to undergo direct cardiac SWT or sham treatment in addition to coronary bypass surgery. The primary efficacy endpoint was the improvement in LVEF measured by cardiac magnetic resonance imaging from baseline to 360 days. RESULTS: Overall, 63 patients were randomized, out of which 30 patients of the SWT group and 28 patients of the Sham group attained 1-year follow-up of the primary endpoint. Greater improvement in LVEF was observed in the SWT group (Δ from baseline to 360 days: SWT 11.3%, SD 8.8; Sham 6.3%, SD 7.4, P = .0146). Secondary endpoints included the 6-minute walking test, where patients randomized in the SWT group showed a greater Δ from baseline to 360 days (127.5 m, SD 110.6) than patients in the Sham group (43.6 m, SD 172.1) (P = .028) and Minnesota Living with Heart Failure Questionnaire score on day 360, which was 11.0 points (SD 19.1) for the SWT group and 17.3 points (SD 15.1) for the Sham group (P = .15). Two patients in the treatment group died for non-device-related reasons. CONCLUSIONS: In conclusion, the CAST-HF trial indicates that direct cardiac SWT, in addition to coronary bypass surgery improves LVEF and physical capacity in patients with ischaemic heart failure.

[Recommendations of the S3 Guideline "Use of Extracorporeal Circulation (ECLS/ ECMO) for Cardiac and Circulatory Failure" of the Association of Scientific Medical Societies in Germany]. / Empfehlungen der S3-Leitlinie (AWMF) "Einsatz der extrakorporalen Zirkulation (ECLS/ECMO) bei Herz- und Kreislaufversagen".

In recent years, the use of mechanical support for patients with cardiac or circulatory failure has continuously increased, leading to 3,000 ECLS/ECMO (extracorporeal life support/extracorporeal membrane oxygenation) implantations annually in Germany. Due to the lack of guidelines, there is an urgent need for evidence-based recommendations addressing the central aspects of ECLS/ECMO therapy. In July 2015, the generation of a guideline level S3 according to the standards of the Association of the Scientific Medical Societies in Germany (AWMF) was announced by the German Society for Thoracic and Cardiovascular Surgery (GSTCVS). In a well-structured consensus process, involving experts from Germany, Austria and Switzerland, delegated by 16 scientific societies and the patients' representation, the guideline "Use of extracorporeal circulation (ECLS/ECMO) for cardiac and circulatory failure" was created under guidance of the GSTCVS, and published in February 2021. The guideline focuses on clinical aspects of initiation, continuation, weaning and aftercare, herein also addressing structural and economic issues. This article presents an overview on the methodology as well as the final recommendations.

[Use of extracorporeal circulation (ECLS/ECMO) for cardiac and circulatory failure : Short version of the S3 guideline]. / Einsatz der extrakorporalen Zirkulation (ECLS/ECMO) bei Herz- und Kreislaufversagen : Kurzversion der AWMF-S3-Leitlinie.

In Germany, a remarkable increase regarding the usage of extracorporeal membrane oxygenation (ECMO) and extracorporeal life support (ECLS) systems has been observed in recent years with approximately 3000 ECLS/ECMO implantations annually since 2015. Despite the widespread use of ECLS/ECMO, evidence-based recommendations or guidelines are still lacking regarding indications, contraindications, limitations and management of ECMO/ECLS patients. Therefore in 2015, the German Society of Thoracic and Cardiovascular Surgery (GSTCVS) registered the multidisciplinary S3 guideline "Use of extracorporeal circulation (ECLS/ECMO) for cardiac and circulatory failure" to develop evidence-based recommendations for ECMO/ECLS systems according to the requirements of the Association of the Scientific Medical Societies in Germany (AWMF). Although the clinical application of ECMO/ECLS represents the main focus, the presented guideline also addresses structural and economic issues. Experts from 17 German, Austrian and Swiss scientific societies and a patients' organization, guided by the GSTCVS, completed the project in February 2021. In this report, we present a summary of the methodological concept and tables displaying the recommendations for each chapter of the guideline.

Infective endocarditis and neurologic events: indications and timing for surgical interventions.

A therapeutic dilemma arises when infective endocarditis (IE) is complicated by a neurologic event. Postponement of surgery up to 4 weeks is recommended by the guidelines, however, this negatively impacts outcomes in many patients with an urgent indication for surgery due to uncontrolled infection, disease progression, or haemodynamic deterioration. The current literature is ambiguous regarding the safety of cardiopulmonary bypass in patients with recent neurologic injury. Nevertheless, most publications demonstrate a lower risk for secondary haemorrhagic conversion of uncomplicated ischaemic lesions than the risk for recurrent embolism under antibiotic treatment. Here, we discuss the current literature regarding neurologic stroke complicating IE with an indication for surgery.

Five-year outcomes of different techniques for minimally invasive mitral valve repair in Barlow's disease.

OBJECTIVES: Barlow's disease is a specific sub-form of mitral valve (MV) disease, characterized by diffuse excessive tissue and multi segment prolapse. The anterolateral mini-thoracotomy represents the standard access for MV regurgitation in many centres. It still remains unclear which surgical technique provides the best results. Therefore, the aim of this study was to compare operative safety and mid-term outcomes after (i) isolated annuloplasty, (ii) use of additional artificial chordae or (iii) leaflet resection in patients suffering from Barlow's disease undergoing minimally invasive MV repair. METHODS: A consecutive series of patients suffering from Barlow's disease undergoing minimally invasive MV surgery between 2001 and 2020 were analysed (n = 246). Patients were grouped and analysed according to the used surgical technique. The primary outcome was a modified Mitral Valve Academic Research Consortium combined end-point of mortality, reoperation due to repair failure or reoccurrence of severe mitral regurgitation within 5 years. The secondary outcome included operative success and safety up to 30 days. RESULTS: No significant difference was found between the 3 surgical techniques with regard to operative safety (P = 0.774). The primary outcome did not differ between groups (P = 0.244). Operative success was achieved in 93.5% and was lowest in the isolated annuloplasty group (77.1%). Conversion to MV replacement was increased in patients undergoing isolated annuloplasty (P < 0.001). CONCLUSIONS: Isolated annuloplasty, use of additional artificial chordae and leaflet resection represent feasible techniques in Barlow patients undergoing minimally invasive MV surgery with comparable 5-year results. In view of the increased conversion rate in the annuloplasty group, the pathology should not be oversimplified.

Randomized comparison of HARVesting the Left Internal Thoracic Artery in a skeletonized versus pedicled technique: the HARVITA trial-study protocol.

Latest research has indicated a potential adverse effect on graft patency rates and clinical outcomes with skeletonizing the left internal thoracic artery. We aim to provide a prospective, randomized, multicentre trial to compare skeletonized versus pedicled harvesting technique of left internal thoracic artery concerning graft patency rates and patient survival. A total of 1350 patients will be randomized to either skeletonized or pedicled harvesting technique and undergo surgical revascularization. Follow-up will be performed at 30 days, 1 year, 2 years and 5 years after surgery. The primary outcome will be death or left internal thoracic artery graft occlusion in coronary computed tomography angiography or invasive angiography within 2 years (+/- 3 months) after surgery. The secondary outcome will be major adverse cardiac events (composite outcome of all-cause death, myocardial infarction and repeated revascularization) within 1 year, 2 years and 5 years after surgery. The primary end point will be compared in the modified intention-to-treat population between the two treatment groups using Kaplan-Meier graphs, together with log-rank testing. Hereby, we present the study protocol of the first adequately powered prospective, randomized, multicentre trial which compares skeletonized and pedicled harvesting technique of left internal thoracic artery regarding graft patency rates and patient survival.

Sex-specific troponin and creatine kinase thresholds after coronary bypass surgery.

BACKGROUND: The impact of sex-differences on the release of cardiac biomarkers after coronary artery bypass grafting (CABG) remains unknown. The aim of our study was to (a) investigate the impact of sex-differences in cardiac biomarker release after CABG and (b) determine sex-specific thresholds for high-sensitivity troponin (hs-cTn) and creatine kinase-MB (CK-MB) associated with 30-day major adverse cardiovascular event (MACE) and mortality. METHODS: A consecutive cohort of 3687 patients (female: n= 643 (17.4%); male: 3044 (82.6%) undergoing CABG from 2008-2021 in two tertiary university centers with serial postoperative cTn and CK-MB measurement was analyzed. The composite primary outcome was MACE at 30 days. Secondary endpoints were 30-day mortality and five-year mortality and MACE. Sex-specific thresholds for cTn and CK-MB were determined. RESULTS: Lower levels of cTn were found in women after CABG (69.18 vs. 77.57 xURL; p<0.001). Optimal threshold value for cTn was calculated at 94.36 times the URL for female and 206.07 times the URL for male patients to predict 30-day MACE. Female patients missed by a general threshold had increased risk for MACE or death within 30 days (cTn: MACE: OR 3.78 CI: 1.03-13.08; p=0.035; death: OR 4.98; CI: 1.20.-20.61; p=0.027; CK-MB: MACE: OR 10.04; CI: 2.07-48.75; p<0.001; death: OR 13.59; CI: 2.66-69.47; p=0.002). CONCLUSIONS: We provide evidence for sex-specific differences in the outcome and biomarker release after CABG. Sex-specific cut-offs are necessary for the diagnosis of perioperative myocardial injury to improve outcomes of women after CABG.

Postoperative cardiac biomarker release is not associated with myocardial mass in computer tomography scans.

OBJECTIVES: Myocardial hypertrophy results in increased levels of cardiac biomarkers in healthy individuals and in patients suffering from acute myocardial infarction. The influence of cardiac mass on postoperative cardiac biomarkers release remains unclear. This study investigated the correlation between myocardial mass and the release of high-sensitivity cardiac Troponin T (hs-cTnT) and creatine kinase-myocardial band (CK-MB) after isolated aortic valve replacement (AVR) or bypass surgery. METHODS: Myocardial mass of a consecutive retrospective series of patients was measured automatically using preoperative computer tomography scans (636 patients, AVR = 251; bypass surgery = 385). Levels of cardiac biomarkers were measured before and serially after surgery. Spearman and Pearson correlation and a multivariate regression model was performed to measure the degree of association between myocardial mass and the release of hs-cTnT and CK-MB. RESULTS: Patients were divided into 3 tertiles according to their myocardial mass index. Higher biomarker levels were measured preoperatively in the upper tertile of patients undergoing AVR (P = 0.004) or bypass surgery (P < 0.001). Patients with different heart sizes showed no differences in postoperative biomarker release neither after AVR nor bypass surgery. No statistical significant correlation was observed between myocardial mass index and postoperative release of hs-cTnT or CK-MB in any subgroup (ρ maximum 0.106). CONCLUSIONS: Postoperative biomarker release is not correlated with myocardial mass. Patient factors leading to increased postoperative biomarker levels need to be elucidated in future studies.

Complexity of coronary artery disease and the release of cardiac biomarkers after CABG.

Objective: In patients with complex coronary artery disease (CAD) undergoing cardiac surgery, myocardial protection might be impaired due to microvascular obstruction, resulting in myocardial injury and subsequent biomarker release. Therefore, this study investigated the correlation between the complexity of CAD, reflected by the SYNTAX Score, and the release of cardiac biomarkers after CABG. Methods: In a consecutive series of 919 patients undergoing isolated CABG SYNTAX scores I and II were calculated to assess the complexity of CAD. Levels of high sensitivity cardiac troponin T (hs-cTnT) and creatine kinase-myocardial band (CK-MB) were routinely measured once before and serially after surgery. Patients were divided into tertiles according to their SYNTAX Scores I and II. Spearman correlations and regression models were performed to measure the degree of association between the release of hs-cTnT and CK-MB and the SYNTAX Scores. Results: Patients with a higher SYNTAX Score I had more comorbidities reflected in a higher EuroSCORE II. Preoperatively, higher levels of cardiac biomarkers were found in patients with higher SYNTAX Score II. No correlation was observed between hs-cTnT, CK-MB and SYNTAX Score I or II. Regression models did not show any association between cardiac biomarkers and the complexity of CAD. Conclusion: The complexity of CAD is not associated with the release of cardiac biomarkers after CABG. Factors influencing postoperative biomarker release need to be elucidated in future trials to include postoperative biomarker release into risk stratification models predicting outcome after cardiac surgery.

Minimally invasive mitral valve reconstruction on the fibrillating heart for high-risk patients.

BACKGROUND AND AIM OF THE STUDY: Mitral valve surgery after previous cardiac surgery is technically demanding and risky. In patients after coronary artery bypass grafting (CABG), mitral valve surgery is associated with a high risk of injury to the bypass graft with concomitant myocardial ischemia. An aortic valve prosthesis usually severely impairs access to the mitral valve, so that these patients are often denied surgery. Furthermore, patients with porcelain aorta may be inoperable. METHODS: A series of 10 patients undergoing minimally invasive mitral valve repair via a right-sided anterolateral minithoracotomy without aortic cross-clamping on the fibrillating heart was investigated. Four patients had an aortic valve prosthesis in situ, six patients had undergone previous CABG, and two patients presented with porcelain aorta. RESULTS: Reconstruction was possible in nine patients. Cannulation was performed femorally in three patients, and via the axillary artery in seven patients. No fatalities were observed. One patient required rethoracotomy for bleeding and subsequently developed a right-sided pneumonia, and a second patient experienced lower-limb ischemia. The postoperative course of the other eight patients was uneventful. No patient presented with significant residual mitral insufficiency at control echocardiography. CONCLUSION: Minimally invasive mitral valve reconstruction via a right-sided minithoracotomy represents an attractive surgical option in a high-risk reoperative setting.

A qualitative improvement program for minimally invasive mitral surgery: technical advancements ameliorate outcome and operative times.

OBJECTIVES: Minimally invasive mitral valve surgery (MIMVS) has evolved over the last 2 decades. The aim of the study was to identify the impact of era and technical improvements on perioperative outcome after MIMVS. METHODS: A tota of 1000 patients (mean age: 60.8 ± 12.7 years, 60.3% male) underwent video-assisted or totally endoscopic MIMVS between 2001 and 2020 in a single institution. Three technical modalities were introduced during the observed period: (i) 3D visualization, (ii) use of premeasured artificial chordae (PTFE loops) and (iii) preoperative CT scans. Comparisons were made before and after the introduction of technical improvements. RESULTS: A total of 741 patients underwent isolated mitral valve (MV) procedure, whereas 259 received concomitant procedures. These consisted of tricuspid valve repair (208), left atrium ablation (145) and persistent foramen ovale or atrial septum defect (ASD) closure (172). The aetiology was degenerative in 738 (73.8%) patients and functional in 101 patients (10.1%). A total of 900 patients received MV repair (90%), and 100 patients (10%) underwent MV replacement. Perioperative survival was 99.1%, and periprocedural success 93.5% with a periprocedural safety of 96.3%. Improvement in periprocedural safety attributed to the lower rates of postoperative low output (P = 0.025) and less reoperations for bleeding (P < 0.001). 3D visualization improved cross-clamp (P = 0.001) but not cardiopulmonary bypass times. The use of loops and preoperative CT scan both had no impact on periprocedural success or safety but improved cardiopulmonary bypass and cross-clamp times (both P < 0.001). CONCLUSIONS: Increased surgical experience improves safety in MIMVS. Technical improvements are related to increased operative success and decreased operative times in patients undergoing MIMVS.

Association of High-Sensitivity Cardiac Troponin T With 30-Day and 5-Year Mortality After Cardiac Surgery.

BACKGROUND: The relevance of perioperative myocardial injury (PMI) after cardiac surgery for 30-day mortality and long-term survival remains to be determined. OBJECTIVES: This study assessed the association of PMI after cardiac surgery, reflected by postoperative troponin release, with 30-day mortality and long-term survival after: 1) coronary artery bypass grafting (CABG); 2) isolated aortic valve replacement (AVR) surgery; and 3) all other cardiac surgeries. METHODS: A consecutive cohort of 8,292 patients undergoing cardiac surgery with serial perioperative high-sensitivity cardiac troponin T (hs-cTnT) measurements was retrospectively analyzed. The relationship between postoperative hs-cTnT release and 30-day mortality or 5-year mortality was analyzed after adjustment with EuroSCORE II using a Cox proportional hazards model. hs-cTnT thresholds for 30-day and 5-year mortality were determined for isolated CABG (32.3%), AVR (14%), and other cardiac surgery (53.8%). RESULTS: High postoperative hs-cTnT levels were associated with higher 30-day mortality but not 5-year mortality. In CABG, median peak concentration of postoperative hs-cTnT was 1,044 ng/L, in AVR it was 502 ng/L, and in other cardiac surgery it was 1,110 ng/L. hs-cTnT thresholds defining mortality-associated PMI were as follows: for CABG, 2,385 ng/L (170× the upper reference limit of normal in a seemingly healthy population [URL]); for AVR, 568 ng/L (41× URL); and for other cardiac procedures, 1,873 ng/L (134× URL). hs-cTnT levels above the cutoffs resulted in an HR for 30-day mortality for CABG of 12.56 (P < 0.001), for AVR of 4.44 (P = 0.004), and for other cardiac surgery of 3.97 (P < 0.001). CONCLUSIONS: PMI reflected by perioperative hs-cTnT release is associated with the expected 30-day mortality but not 5-year mortality. Postoperative hs-cTnT cutoffs to identify survival-relevant PMI are higher than suggested in current definitions.

Predictors of safety and success in minimally invasive surgery for degenerative mitral disease.

OBJECTIVES: The aim of this study was to identify predictors of periprocedural success and safety in minimally invasive mitral valve surgery and to determine the impact of pathology localization and repair technique on reoperation-free survival. METHODS: We isolated 686 patients (mean age 60.5, standard deviation 12.3 years, 69.4% male) who underwent surgery for mitral valve prolapse between 2002 and 2020 in a single institution. Patients with concomitant disease, redo or mitral pathology other than degenerative mitral disease were excluded from the analysis. Periprocedural safety was defined as: freedom from perioperative death, myocardial infarction, stroke, use of extracorporeal membrane oxygenation or reoperation for bleeding. Operative success was defined as: successful primary mitral repair without conversion to replacement or to larger thoracic incisions, without residual mitral regurgitation > mild at discharge or reoperation within 30 days. Predictors for perioperative success and safety were identified using univariable and multivariable analyses. The impact of prolapse localization and repair technique on reoperation-free survival was assessed by Cox regression. RESULTS: The mitral repair rate and the need for concomitant tricuspid repair were 94.6% and 16.5%, respectively. Perioperative mortality occurred in 5 patients (0.7%). The criteria for perioperative safety and success were met in 646/686 (94.2%) and 648/686 (94.5%) patients, respectively. The absence of tricuspid disease requiring repair was the only independent predictor of safety in this cohort [hazard ratio (HR) 0.460 (0.225-0.941), P = 0.033]. The only independent predictor of operative success was the use of chordal replacement [0.27 (0.09-0.83), P = 0.022]. Reoperation-free survival was 98.5%, 94.5% and 86.9% at 1, 5 and 10 years, respectively. Posterior leaflet pathology demonstrated a higher reoperation-free survival as compared to other localizations (log-rank P = 0.002). The localization of leaflet pathology but not the repair method was an independent predictor for reoperation-free survival (HR 1.455, 95% confidence interval 1.098-1.930; P = 0.009). CONCLUSIONS: In minimally invasive mitral surgery for degenerative disease, chordal replacement yields higher rates of periprocedural success than leaflet resection. Posterior leaflet pathology is an independent predictor of reoperation-free survival.

Use of extracorporeal circulation (ECLS/ECMO) for cardiac and circulatory failure -A clinical practice Guideline Level 3.

Aims Worldwide applications of extracorporeal circulation for mechanical support in cardiac and circulatory failure, which are referred to as extracorporeal life support (ECLS) or veno-arterial extracorporeal membrane oxygenation (va-ECMO), have dramatically increased over the past decade. In spite of the expanding use and the immense medical as well as socio-economic impact of this therapeutic approach, there has been a lack of interdisciplinary recommendations considering the best available evidence for ECLS treatment. Methods and Results In a multiprofessional, interdisciplinary scientific effort of all scientific societies involved in the treatment of patients with acute cardiac and circulatory failure, the first evidence- and expert consensus-based guideline (level S3) on ECLS/ECMO therapy was developed in a structured approach under regulations of the AWMF (Association of the Scientific Medical Societies in Germany) and under use of GRADE (Grading of Recommendations Assessment, Development and Evaluation) criteria. This article presents all recommendations created by the expert panel, addressing a multitude of aspects for ECLS initiation, continuation, weaning and aftercare as well as structural and personnel requirements. Conclusions This first evidence- and expert consensus-based guideline (level S3) on ECLS/ECMO therapy should be used to apply the best available care nationwide. Beyond clinical practice advice, remaining important research aspects for future scientific efforts are formulated.

[Use of extracorporeal circulation (ECLS/ECMO) for cardiac and circulatory failure : Short version of the S3 guideline]. / Einsatz der extrakorporalen Zirkulation (ECLS/ECMO) bei Herz- und Kreislaufversagen : Kurzversion der AWMF-S3-Leitlinie.

In Germany, a remarkable increase regarding the usage of extracorporeal membrane oxygenation (ECMO) and extracorporeal life support (ECLS) systems has been observed in recent years with approximately 3000 ECLS/ECMO implantations annually since 2015. Despite the widespread use of ECLS/ECMO, evidence-based recommendations or guidelines are still lacking regarding indications, contraindications, limitations and management of ECMO/ECLS patients. Therefore in 2015, the German Society of Thoracic and Cardiovascular Surgery (GSTCVS) registered the multidisciplinary S3 guideline "Use of extracorporeal circulation (ECLS/ECMO) for cardiac and circulatory failure" to develop evidence-based recommendations for ECMO/ECLS systems according to the requirements of the Association of the Scientific Medical Societies in Germany (AWMF). Although the clinical application of ECMO/ECLS represents the main focus, the presented guideline also addresses structural and economic issues. Experts from 17 German, Austrian and Swiss scientific societies and a patients' organization, guided by the GSTCVS, completed the project in February 2021. In this report, we present a summary of the methodological concept and tables displaying the recommendations for each chapter of the guideline.

Donor hypo- and hypernatremia are predictors for increased 1-year mortality after cardiac transplantation.

Donor hypernatremia is known to be associated with initial graft dysfunction in liver transplantation. Controversial data exist regarding the impact of sodium dysregulation on patient survival after heart transplantation (HTX). The aim of this study was to investigate the influence of donor sodium levels on survival in a large cohort of heart transplant recipients from the Eurotransplant registry. From 1997 to 2005, all consecutive adult HTX performed in the Eurotransplant region were included into this study (n = 4641 patients). Multivariate analysis was applied to investigate possible clinical predictors for 1-year post-transplant survival after cardiac transplantation (donor sodium levels, donor age, donor cause of death, recipient age, primary disease, urgency status, cold ischemia time). In multivariate analysis, recipients receiving a donor heart with serum sodium level lower than 130 mmol/l or higher than 170 mmol/l had a 1.25-fold higher risk for 1-year post-transplant mortality than patients with normal donor sodium ranges (P = 0.007). Other independent risk factors for impaired 1-year survival were recipient age, the indication for transplantation and the urgency status of the recipient. Our study demonstrates that hyponatremia as well as hypernatremia show a strong U-shaped correlation with poor survival after cardiac transplantation. Accurate donor management to avoid electrolyte disorder seems to be crucial for ensuring good quality of donor hearts.

Elective frozen-thawed embryo transfer (FET) in women at risk for ovarian hyperstimulation syndrome.

Elective cryopreservation of cultured embryos has become a treatment option for women at risk for ovarian hyperstimulation syndrome (OHSS). The aim of our study was to investigate the outcome of elective cryopreservation and consecutive frozen-thawed embryo transfer (FET) in a large IVF clinic in Austria. A total of 6104 controlled ovarian hyperstimulation cycles (COH) were performed on 2998 patients including 200 patients (6.7%) who were undergoing elective cryopreservation and FET due to high risk of OHSS. We estimated the cumulative live birth rate using the Kaplan-Meier method and evaluated independent predictors for successful live births with a Cox model. A total of 270 frozen-thawed embryo transfers were performed on 200 patients with up to 4 transfers per patient. The first embryo transfer showed a live birth rate of 42.0%, the second transfer showed a cumulative rate of 58.5%. After a total of 4 FETs from the same COH cycle, a cumulative live birth rate of 61.0% per COH cycle could be achieved. Four cases of OHSS occurred amongst these patients (2.0%), all of them of moderate severity. Multivariate analysis identified maternal age, the use of assisted hatching and the number of embryos transferred at the blastocyst stage as independent predictors for cumulative live birth. Our study clearly suggests that elective FET is safe and shows excellent cumulative live birth rates. This concept can, therefore, be used to avoid the severe adverse events caused by COH and the inefficient use of cultured embryos.