Tamer Owais
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Research Interests
Tamer Owais has a total of 31 co-authors. Here are the top co-authors by number of shared publications:
- Mohammad El Garhy
Heart Centre, Zentralklinik Bad Berka, Bad Berka, Germany
3 shared publications Evaldas Girdauskas
Department of Cardiac Surgery, University Hospital Augsburg, Augsburg, Germany
2 shared publicationsThomas Kuntze
Heart Centre, Zentralklinik Bad Berka, Bad Berka, Germany
2 shared publicationsEva Harmel
Department of Cardiology, University Hospital Augsburg, Augsburg, Germany
1 shared publication- Evaldas Girdauskas
Department of Cardiac Surgery, University Hospital Augsburg, 86156 Augsburg, Germany
1 shared publication Friedrich-Wilhelm Mohr
Department of Cardiac Surgery, University of Leipzig, Heart-Center Leipzig, Probstheida, Leipzig, Germany
1 shared publication
Latest Publications
- Open Access
- 30 August 2024
- Published by MDPI AG in Journal of Clinical Medicine
- Vol. 13 (17) , 5164
Outcomes of Valve-in-Valve (VIV) Transcatheter Aortic Valve Replacement (TAVR) after Surgical Aortic Valve Replacement with Sutureless Surgical Aortic Valve Prostheses Perceval™: A Systematic Review of Published Cases
Background: Valve-in-Valve (VIV) transcatheter aortic valve replacement (TAVR) is a potential solution for malfunctioning surgical aortic valve prostheses, though limited data exist for its use in Perceval valves. Methods: searches were performed on PubMed and Scopus up to 31 July 2023, focusing on case reports and series addressing VIV replacement for degenerated Perceval bioprostheses. Results: Our analysis included 57 patients from 27 case reports and 6 case series. Most patients (68.4%) were women, with a mean age of 76 ± 4.4 years and a mean STS score of 6.1 ± 4.3%. Follow-up averaged 9.8 ± 8.9 months, the mean gradient reduction was 15 ± 5.9 mmHg at discharge and 13 ± 4.2 mmHg at follow-up. Complications occurred in 15.7% of patients, including atrioventricular block III in four patients (7%), major bleeding or vascular complications in two patients (3.5%), an annular rupture in two patients (3.5%), and mortality in two patients (3.5%). No coronary obstruction was reported. Balloon-expanding valves were used in 61.4% of patients, predominantly the Sapien model. In the self-expanding group (38.6%), no valve migration occurred, with a permanent pacemaker implantation rate of 9%, compared to 5.7% for balloon-expanding valves. Conclusions: VIV-TAVR using both balloon-expanding and self-expanding technologies is feasible after the implantation of Perceval valves; however, it should be performed by experienced operators with experience both in TAVR and VIV procedures.
- 30 August 2024
- Published by MDPI AG in Journal of Clinical Medicine
- Vol. 13 (17) , 5164
Open AccessOutcomes of Valve-in-Valve (VIV) Transcatheter Aortic Valve Replacement (TAVR) after Surgical Aortic Valve Replacement with Sutureless Surgical Aortic Valve Prostheses Perceval™: A Systematic Review of Published Cases
Background: Valve-in-Valve (VIV) transcatheter aortic valve replacement (TAVR) is a potential solution for malfunctioning surgical aortic valve prostheses, though limited data exist for its use in Perceval valves. Methods: searches were performed on PubMed and Scopus up to 31 July 2023, focusing on case reports and series addressing VIV replacement for degenerated Perceval bioprostheses. Results: Our analysis included 57 patients from 27 case reports and 6 case series. Most patients (68.4%) were women, with a mean age of 76 ± 4.4 years and a mean STS score of 6.1 ± 4.3%. Follow-up averaged 9.8 ± 8.9 months, the mean gradient reduction was 15 ± 5.9 mmHg at discharge and 13 ± 4.2 mmHg at follow-up. Complications occurred in 15.7% of patients, including atrioventricular block III in four patients (7%), major bleeding or vascular complications in two patients (3.5%), an annular rupture in two patients (3.5%), and mortality in two patients (3.5%). No coronary obstruction was reported. Balloon-expanding valves were used in 61.4% of patients, predominantly the Sapien model. In the self-expanding group (38.6%), no valve migration occurred, with a permanent pacemaker implantation rate of 9%, compared to 5.7% for balloon-expanding valves. Conclusions: VIV-TAVR using both balloon-expanding and self-expanding technologies is feasible after the implantation of Perceval valves; however, it should be performed by experienced operators with experience both in TAVR and VIV procedures.
- Open Access
- 28 March 2022
- Published by Springer Nature in The Egyptian Heart Journal
- Vol. 74 (1) , 1-9
Contemporary results of transcatheter mitral valve procedures: bi-centric retrospective analysis
Background: Transcatheter mitral valve-in-valve (TMVIV) or valve-in-ring (TMVIR) replacement offer an alternative therapy for high risk patients. We aimed to highlight the operative and postoperative results of TMVIV and TMVIR procedures. Results: We included all patients underwent TMVIV and TMVIR procedures between 2017 and 2020 at two heart centers in Germany. We included a total of 36 high risk patients in our study where 12 received TMVIV and 24 received TMVIR. All patients underwent TMVIV or TMVIR with Edwards Sapien XT or S3 transcatheter valves (Edwards Lifesciences). The mean age was 79 (75–83 years old). The median (IQR) preoperative STS score was 9 (7–13)% and EuroSCORE II was 14.5% (12–16). The majority of our patients were operated via transapical approach (n = 26) and the minority via transseptal approach (n = 10). Out of our records, none of our patients required reopening for bleeding or any other surgical complications. None of our patients required reintervention during the 6 months follow-up period. One mortality was recorded on fifth postoperative day due to low cardiac output syndrome (obviously because of LVOT obstruction by the anterior mitral leaflet). The average blood loss was 200 ml in the first 24 h in patients underwent transapical approach. Average operative time was 93 min and all patients were immediately extubated after the procedure in the operating room (even the patient with echocardiographically documented LVOT obstruction who died on the fifth postoperative day). Length of Intensive Care Unit stay was 2 ± 1.2 days and length of hospital stay was 4.1 ± 1.2 days. In the follow up period, echocardiograms showed normal prosthetic valve function with low transvalvular gradients, no LVOT obstruction in TMVIR cases and no evidence of valve migration or thrombosis (except in one patient). Concerning 6 months readmission, it was recorded in 2 patients due to right sided heart failure symptoms due to preexisting high degree of tricuspid valve regurge which did not disappear or even decrease after the operation and the other patient due to gastrointestinal bleeding. Conclusions: TMVIV and TMVIR offer an efficient, safe and less invasive alternative in high surgical risk patients.
- 28 March 2022
- Published by Springer Nature in The Egyptian Heart Journal
- Vol. 74 (1) , 1-9
Open AccessContemporary results of transcatheter mitral valve procedures: bi-centric retrospective analysis
Background: Transcatheter mitral valve-in-valve (TMVIV) or valve-in-ring (TMVIR) replacement offer an alternative therapy for high risk patients. We aimed to highlight the operative and postoperative results of TMVIV and TMVIR procedures. Results: We included all patients underwent TMVIV and TMVIR procedures between 2017 and 2020 at two heart centers in Germany. We included a total of 36 high risk patients in our study where 12 received TMVIV and 24 received TMVIR. All patients underwent TMVIV or TMVIR with Edwards Sapien XT or S3 transcatheter valves (Edwards Lifesciences). The mean age was 79 (75–83 years old). The median (IQR) preoperative STS score was 9 (7–13)% and EuroSCORE II was 14.5% (12–16). The majority of our patients were operated via transapical approach (n = 26) and the minority via transseptal approach (n = 10). Out of our records, none of our patients required reopening for bleeding or any other surgical complications. None of our patients required reintervention during the 6 months follow-up period. One mortality was recorded on fifth postoperative day due to low cardiac output syndrome (obviously because of LVOT obstruction by the anterior mitral leaflet). The average blood loss was 200 ml in the first 24 h in patients underwent transapical approach. Average operative time was 93 min and all patients were immediately extubated after the procedure in the operating room (even the patient with echocardiographically documented LVOT obstruction who died on the fifth postoperative day). Length of Intensive Care Unit stay was 2 ± 1.2 days and length of hospital stay was 4.1 ± 1.2 days. In the follow up period, echocardiograms showed normal prosthetic valve function with low transvalvular gradients, no LVOT obstruction in TMVIR cases and no evidence of valve migration or thrombosis (except in one patient). Concerning 6 months readmission, it was recorded in 2 patients due to right sided heart failure symptoms due to preexisting high degree of tricuspid valve regurge which did not disappear or even decrease after the operation and the other patient due to gastrointestinal bleeding. Conclusions: TMVIV and TMVIR offer an efficient, safe and less invasive alternative in high surgical risk patients.
- Open Access
- 15 June 2020
- Published by Wiley in Cardiology Research and Practice
- Vol. 2020, 1-6
Contemporary Results of Transcatheter Aortic Valve Replacement in Obese Patients
Background. Little research has been conducted to explore the postoperative outcomes of obese patients after transfemoral transcatheter aortic valve replacement (TF-TAVR). Objective. We investigated the influence of body mass index (BMI) on 1-year outcomes after TF-TAVR. Methods. We included retrospectively 1609 high- and intermediate-risk TAVR patients (mean EuroSCORE II 21 ± 11) operated under general anesthesia between March 2014 and March 2018 in central hospital, Bad Berka, Germany. We stratified the patients according to BMI. Results. Our demographic data analysis showed 41% of patients were male and the mean age was 78 (range, 61–92 years). According to the WHO classification, 33% patients had normal weight, 42% were defined as overweight, and 22% were obese. Obese patients showed statistically significant difference in their clinical parameters as having higher incidence of hypertension, diabetes mellitus, pulmonary hypertension, and chronic obstructive pulmonary disease; on the contrary, obese patients were found to be younger than others. We found no differences in valve types and sizes among the different BMI categories. Our mortality rate during the 1-year follow-up period was 17.8% (287 patients). Mortality was significantly higher in patients with BMI < 25 kg/m2 (1 year mortality 149 patients 28.2% in patients with BMI < 25 kg/m2 vs. 138 patients 12.6% in patients with BMI ≥ 25 kg/m2; ). Even after considering the confounding risk factors, BMI ≥ 25 kg/m2 was independently associated with reduced 1 year mortality (odds ratio (OR): 0.36, 95% confidence interval (CI): 0.21–0.6; ) in multivariate logistic regression analysis. The rate of vascular complication was higher in patients with BMI ≥ 25 kg/m2. However, the rate of blood transfusion was higher in patients with BMI < 25 kg/m2. All other serious complications occurred with equal distribution in both groups. Conclusion. In our single-center study, BMI ≥ 25 kg/m2 was independently associated with lower 1 year mortality after TF-TAVR.- 15 June 2020
- Published by Wiley in Cardiology Research and Practice
- Vol. 2020, 1-6
Open AccessContemporary Results of Transcatheter Aortic Valve Replacement in Obese Patients
Background. Little research has been conducted to explore the postoperative outcomes of obese patients after transfemoral transcatheter aortic valve replacement (TF-TAVR). Objective. We investigated the influence of body mass index (BMI) on 1-year outcomes after TF-TAVR. Methods. We included retrospectively 1609 high- and intermediate-risk TAVR patients (mean EuroSCORE II 21 ± 11) operated under general anesthesia between March 2014 and March 2018 in central hospital, Bad Berka, Germany. We stratified the patients according to BMI. Results. Our demographic data analysis showed 41% of patients were male and the mean age was 78 (range, 61–92 years). According to the WHO classification, 33% patients had normal weight, 42% were defined as overweight, and 22% were obese. Obese patients showed statistically significant difference in their clinical parameters as having higher incidence of hypertension, diabetes mellitus, pulmonary hypertension, and chronic obstructive pulmonary disease; on the contrary, obese patients were found to be younger than others. We found no differences in valve types and sizes among the different BMI categories. Our mortality rate during the 1-year follow-up period was 17.8% (287 patients). Mortality was significantly higher in patients with BMI < 25 kg/m2 (1 year mortality 149 patients 28.2% in patients with BMI < 25 kg/m2 vs. 138 patients 12.6% in patients with BMI ≥ 25 kg/m2; ). Even after considering the confounding risk factors, BMI ≥ 25 kg/m2 was independently associated with reduced 1 year mortality (odds ratio (OR): 0.36, 95% confidence interval (CI): 0.21–0.6; ) in multivariate logistic regression analysis. The rate of vascular complication was higher in patients with BMI ≥ 25 kg/m2. However, the rate of blood transfusion was higher in patients with BMI < 25 kg/m2. All other serious complications occurred with equal distribution in both groups. Conclusion. In our single-center study, BMI ≥ 25 kg/m2 was independently associated with lower 1 year mortality after TF-TAVR. - 20 May 2020
- Published by HMP Communications, LLC in Journal of Invasive Cardiology
- Vol. 32 (9) , 330-334
Transcatheter Aortic Valve Replacement Without the Use of Contrast Medium: An Alternative Safe Implantation Technique
New transcatheter equipment and accumulated experience have stimulated further refinements in implantation techniques. We aimed to compare the outcomes of transfemoral transcatheter aortic valve replacement with and without the use of contrast medium in patients with glomerular filtration rate from Journal of Invasive Cardiology.
- 20 May 2020
- Published by HMP Communications, LLC in Journal of Invasive Cardiology
- Vol. 32 (9) , 330-334
Transcatheter Aortic Valve Replacement Without the Use of Contrast Medium: An Alternative Safe Implantation Technique
New transcatheter equipment and accumulated experience have stimulated further refinements in implantation techniques. We aimed to compare the outcomes of transfemoral transcatheter aortic valve replacement with and without the use of contrast medium in patients with glomerular filtration rate from Journal of Invasive Cardiology.
- Open Access
- 4 January 2017
- Published by MedCrave Group Kft. in Journal of Cardiology & Current Research
- Vol. 8 (1) , 1-8
Timing and Outcome of Coronary Artery Bypass Grafting in STEMI: On-Pump and off-Pump Dilemma
Background: Our objective in this multicenter retrospective study is to discuss the optimum timing for CABG after STEMI. The second question is whether the Off-Pump technique differs regarding the timing or affects the outcome compared to the On-Pump technique. Methods: Between September 2009 and June 2016 in Saudi German hospitals group in Saudi Arabia and central Hospital BadBerka in Germany, 379 STEMI patients, who were not candidates for or failed PCI; were operated for CABG. 200 (52.77%) were operated Off-Pump and 179(47.23%) On-Pump; with an age range of 36-63years. 195 males in the off-pump patients (97.5%) and 175 males (97.76%) in the on-pump patients. we arranged them into 2main groups; group A as off-Pump and group B as on-pump. Both groups were further subdivided into groups A1 (off-pump early surgery; 100 patients), group A2 (off-pump late surgery; 100 patients) group B1 (on-pump early surgery; 88 patients) and group B2 (late surgery; 91 patients). We excluded patients with Complicated PCI, Mechanical complications, Cardiogenic shock, Life threatening arrhythmias and Late presentation of ischemia or infarction after PCI. Results: 25 mortalities occurred in early operated cases. There were no intraoperative mortality in the groups operated late after the infarction, and only one late postoperative mortality in group B2. 9 mortalities in group A1 (4.5% of the off-pump CABG-9% of group A1) and 16 mortalities of group B (8.9% of group B, 15 cases in group B1; 17% and 1 case in group B2; 1.09%). There was significant statistical difference between group A and group B, A1 and A2, B1 and B2; regarding the intra-and postoperative mortality with p-value of 0.004, 0.0022, 0.001 intraoperatively and 0.0047, 0.001, 0.003 postoperatively. The postoperative duration for mechanical ventilation was longer in group B than in group A, and longer in group A1 compared to group A2. The use of intra-aortic balloon pump was more in group B than A and more in A1 compared to A2 also more in cases of group B1 than B2. The use of inotropic support was more in group B than A while it was less in A2 than A1 and more in B1 than B2. The total ICU and hospital stay were longer in cases of B than A and more in A1 than A2, also longer in B1 than B2. The intra and post operative arrhythmias and complications were more in A1 than A2 and in B1 than B2. Conclusion: The more we wait after STEMI for surgical intervention for cases not candidate or failed for primary PCI, the better the outcome of surgery With no sharp time limit for postponing the surgery.
- 4 January 2017
- Published by MedCrave Group Kft. in Journal of Cardiology & Current Research
- Vol. 8 (1) , 1-8
Open AccessTiming and Outcome of Coronary Artery Bypass Grafting in STEMI: On-Pump and off-Pump Dilemma
Background: Our objective in this multicenter retrospective study is to discuss the optimum timing for CABG after STEMI. The second question is whether the Off-Pump technique differs regarding the timing or affects the outcome compared to the On-Pump technique. Methods: Between September 2009 and June 2016 in Saudi German hospitals group in Saudi Arabia and central Hospital BadBerka in Germany, 379 STEMI patients, who were not candidates for or failed PCI; were operated for CABG. 200 (52.77%) were operated Off-Pump and 179(47.23%) On-Pump; with an age range of 36-63years. 195 males in the off-pump patients (97.5%) and 175 males (97.76%) in the on-pump patients. we arranged them into 2main groups; group A as off-Pump and group B as on-pump. Both groups were further subdivided into groups A1 (off-pump early surgery; 100 patients), group A2 (off-pump late surgery; 100 patients) group B1 (on-pump early surgery; 88 patients) and group B2 (late surgery; 91 patients). We excluded patients with Complicated PCI, Mechanical complications, Cardiogenic shock, Life threatening arrhythmias and Late presentation of ischemia or infarction after PCI. Results: 25 mortalities occurred in early operated cases. There were no intraoperative mortality in the groups operated late after the infarction, and only one late postoperative mortality in group B2. 9 mortalities in group A1 (4.5% of the off-pump CABG-9% of group A1) and 16 mortalities of group B (8.9% of group B, 15 cases in group B1; 17% and 1 case in group B2; 1.09%). There was significant statistical difference between group A and group B, A1 and A2, B1 and B2; regarding the intra-and postoperative mortality with p-value of 0.004, 0.0022, 0.001 intraoperatively and 0.0047, 0.001, 0.003 postoperatively. The postoperative duration for mechanical ventilation was longer in group B than in group A, and longer in group A1 compared to group A2. The use of intra-aortic balloon pump was more in group B than A and more in A1 compared to A2 also more in cases of group B1 than B2. The use of inotropic support was more in group B than A while it was less in A2 than A1 and more in B1 than B2. The total ICU and hospital stay were longer in cases of B than A and more in A1 than A2, also longer in B1 than B2. The intra and post operative arrhythmias and complications were more in A1 than A2 and in B1 than B2. Conclusion: The more we wait after STEMI for surgical intervention for cases not candidate or failed for primary PCI, the better the outcome of surgery With no sharp time limit for postponing the surgery.
- Open Access
- 7 December 2010
- Published by Oxford University Press (OUP) in Interactive CardioVascular and Thoracic Surgery
- Vol. 12 (5) , 875-877
Excision of a left atrial myxoma via a minimally-invasive technique: a possible routine access
We would like to present our experience of surgical excision of intracardiac tumors using a video-assisted minimally-invasive cardiac surgery (MIC) t
- 7 December 2010
- Published by Oxford University Press (OUP) in Interactive CardioVascular and Thoracic Surgery
- Vol. 12 (5) , 875-877
Open AccessExcision of a left atrial myxoma via a minimally-invasive technique: a possible routine access
We would like to present our experience of surgical excision of intracardiac tumors using a video-assisted minimally-invasive cardiac surgery (MIC) t