Wael Hassanein

Effect of surgeon on transprosthetic gradients after aortic valve replacement with Freestyle® stentless bioprosthesis and its consequences: A follow-up study in 587 patients

BackgroundThe implantation of stentless valves is technically demanding and the outcome may depend on the performance of surgeons. We studied systematically the role of surgeons and other possible determinants for mid-term survival, postoperative gradients and Quality of Life (QoL) after aortic valve replacement (AVR) with Freestyle® stentless bioprostheses.MethodsBetween 1996 and 2003, 587 patients (mean 75 years) underwent AVR with stentless Medtronic Freestyle® bioprostheses. Follow-up was 99% complete. Determinants of morbidity, mortality, survival time and QoL were evaluated by multiple, time-related, regression analysis. Risk models were built for all sections of the Nottingham Health Profile (NHP): energy, pain, emotional reaction, sleep, social isolation and physical mobilityResultsActuarial freedom from aortic valve re-operation, structural valve deterioration, non-structural valve dysfunction, prosthetic valve endocarditis and thromboembolic events at 6 years were 95.9 ± 2.1%, 100%, 98.7 ± 0.5%, 97.0 ± 1.5%, 79.6 ± 4.3%, respectively. The actuarial freedom from bleeding events at 6 years was 93.1 ± 1.9%. Estimated survival at 6 years was similar to the age-matched German population (61.4 ± 3.8 %). Predictors of survival time were: diabetes mellitus, atrial fibrillation, peripheral vascular disease, renal dysfunction, female gender > 80 years and patients < 165 cm with BMI < 24. Predictive models showed characteristic profiles and good discriminative powers (c-indexes > 0.7) for each of the 6 QoL sections. Early transvalvular gradients were identified as independent risk factors for impaired physical mobility (c-index 0.77, p < 0.002). A saturated propensity score identified besides patient related factors (e.g. preoperative gradients, ejection fraction, haematological factors) indexed geometric orifice area, subcoronary implantation technique and individual surgeons as predictors of high gradients.ConclusionIn addition to the valve size (in relation to body size), subcoronary technique (versus total root) and various patient-related factors the risk of elevated gradients after stentless valve implantation depends, considerably on the individual surgeon.Although there was no effect on survival time and most aspects of QoL, higher postoperative transvalvular gradients affect physical mobility after AVR.

Short term outcomes of total arterial coronary revascularization in patients above 65 years: a propensity score analysis

BackgroundDespite the advantages of bilateral mammary coronary revascularization, many surgeons are still restricting this technique to the young patients. The objective of this study is to demonstrate the safety and potential advantages of bilateral mammary coronary revascularization in patients older than 65 years.MethodsGroup I included 415 patients older than 65 years with exclusively bilateral mammary revascularization. Using a propensity score we selected 389 patients (group II) in whom coronary bypass operations were performed using the left internal mammary artery and the great saphenous vein.ResultsThe incidence of postoperative stroke was higher in group II (1.5% vs. 0%, P = 0.0111). The amount of postoperative blood loss was higher in group I (908 ± 757 ml vs. 800 ± 713 ml, P = 0.0405). There were no other postoperative differences between both groups.ConclusionBilateral internal mammary artery revascularization can be safely performed in patients older than 65 years. T-graft configuration without aortic anastomosis is particularly beneficial in this age group since it avoids aortic manipulation, which is an important risk factor for postoperative stroke.

Technical aspects of composite arterial T-grafts: Estimation of required conduit length by a simple formula

BACKGROUND When composite arterial T-grafts are used, uncertainty persists as to whether the RIMA will be long enough to reach the RCA. We present a formula for the preoperative estimation of the required conduit length. METHODS The following formula was created to estimate the required conduit length for a sequential graft, starting from the proximal RIMA-LIMA T-graft anastomosis, passing the PLA, and ending at the PDA: 2.14 x ([2 x LV wall thickness [WT]) + end-diastolic diameter (EDD)]. The estimated length was compared to the measured length in 100 patients undergoing off-pump revascularisation with BIMA T-grafts. RESULTS There were no hospital deaths, no major infarctions and no wound complications. The required conduit length varied from 11.5 cm to 19 cm (average 14.9 +/- 1.4 cm) and was excellently predicted by the formula (paired T-test: P < 0.001, r = 0.86, average overestimation: 0.55 cm). CONCLUSION The formula reliably determines the minimum required conduit length. We recommend this formula for preoperative decision making when considering the choice of graft and the length of RIMA harvesting. To facilitate calculation a simplified version is useful: 2 x EDD + 4 x WD + 1. Avoiding uncertainty about the sufficiency of the RIMA length may contribute to the spread of this technique.

Hyperkalemic Blood versus Crystalloid Cardioplegia in Longer Clamping Times

The 715 patients who had crystalloid cardioplegia were compared with 5419 who had cold hyperkalemic blood cardioplegia for isolated coronary artery grafting from 1996 through 2001. Creatine kinase-MB was measured preoperatively, at 90 min, and 7 hours after the end of extracorporeal circulation. Correlation of post-bypass creatine kinase-MB release with aortic crossclamp time and other variables in the two cardioplegia groups was made using dichotomous encoding of cardioplegia in a multivariate linear regression model. Creatine kinase-MB levels 90 min after bypass were higher in patients who had crystalloid cardioplegia than in those who had blood cardioplegia. There was a linear relationship between aortic crossclamp time and post-bypass creatine kinase-MB release in both cardioplegia groups. Post-bypass creatine kinase-MB release increased with aortic crossclamp time independently of other factors and significantly more with crystalloid cardioplegia than with blood cardioplegia (the slope of the regression line was 0.230 versus 0.106). Intraaortic balloon pumping was used less frequently in the blood cardioplegia group. There was an advantage with blood cardioplegia for myocardial protection in longer aortic crossclamp times for isolated coronary bypass grafting.

The Use of Bilateral Internal Mammary Artery Grafting in Different Degrees of Obesity.

Background Obesity is a limiting factor for the use of bilateral internal mammary arteries (BIMAs). Therefore, we assessed the safety of their use in different degrees of obesity. Patients and Methods We studied two groups of patients with obesity using propensity matching. The first group received single internal mammary artery and saphenous vein grafts (SIMA group, 526 patients) and the second group received bilateral internal mammary arteries (BIMA group, 526 patients). Patients were classified further according to their body mass index (BMI) into overweight (BMI = 25‐29.9 kg/m2), obese (BMI = 30‐34.9 kg/m2), and severely obese (BMI ≥ 35 kg/m2). Results Preoperative data were similar regarding age (62.78 ± 9.96 vs. 62.98 ± 9.66 years; p = 0.734), female sex (17.5 vs. 18.6%; p = 0.631), diabetes mellitus (26.3 vs. 27.2%; p = 0.74), EuroSCORE (3.21 ± 2.23 vs. 3.18 ± 2.41; p = 0.968), and COPD (16 vs. 16%; p = 1). No significant differences were noticed between the two groups regarding the number of peripheral anastomoses (3.09 ± 0.84 vs. 3.12 ± 0.83; p = 0.633), myocardial infarction (1.7 vs. 1.7%; p = 1), reexploration (1.3 vs. 2.1%; p = 0.34), deep sternal wound infection (DSWI) (2.1 vs. 2.9%; p = 0.43), and 30‐day mortality (0.8 vs. 1.1%; p = 0.53). Multivariate analysis identified BMI and intensive care unit stay as independent predictors for DSWI. However, postoperative blood loss (694.56 ± 631.84 vs. 811.67 ± 688.73 mL; p < 0.001) and the incidence of pneumothorax (1 vs. 2.7%; p = 0.037) were higher in BIMA group. Conclusion Patients with obesity can benefit from BIMA grafting. However, postoperative blood loss and the incidence of pneumothorax can be higher using this technique.

Medtronic Freestyle aortic bioprosthesis: a potential option for haemodialysis patients †

OBJECTIVES End-stage renal disease patients on regular haemodialysis are at higher risk of calcification. Therefore, many surgeons have concerns regarding the implantation of bioprostheses in such patients. The haemodynamic advantages of stentless aortic bioprostheses support their use; however, these have not been studied yet in end-stage renal disease patients. We studied accordingly the early and mid-term outcomes of aortic valve replacement (AVR) using Medtronic Freestyle stentless aortic bioprostheses in this subset of patients in comparison with stented aortic bioprostheses. METHODS We retrospectively studied two groups of consecutive patients on regular haemodialysis who required AVR between 2007 and 2013. Non-Freestyle (NFS) group received stented aortic bioprostheses (36 patients) and Freestyle (FS) group received Medtronic Freestyle aortic bioprostheses (48 patients). Follow-up ranged from 2 to 76 months with a mean follow-up of 36.3 ± 25 months. RESULTS Patients in both groups showed similar demographic characters regarding age (76.4 ± 8.1 vs 74.9 ± 7.2 years; P = 0.35), male gender (58 vs 60%; P = 0.57) and diabetes mellitus (42 vs 48%; P = 0.57). Smaller aortic bioprostheses were implanted in the NFS (23.3 ± 1.2 vs 25.4 ± 2.1; P < 0.001) with consequently higher postoperative mean gradients (14.1 ± 4.1 vs 11.9 ± 5.3 mmHg; P = 0.004). No significant differences were noted regarding postoperative neurological disorder (8 vs 12%; P = 0.73), deep sternal wound infection (3 vs 4%; P = 0.68), re-exploration (8 vs 8%; P = 0.91) and in-hospital mortality (6 vs 4%; P = 0.92). Mid-term follow-up showed higher prosthetic valve calcification and/or sclerosis in NFS group (25 vs 6%; P = 0.015), whereas no significant differences were noticed between the two groups regarding stroke (0 vs 8%; P = 0.13), endocarditis (0 vs 4%; P = 0.50), 36- and 72-month survival (51 ± 2%, 14 ± 4% vs 55 ± 2%, 19 ± 3%, respectively; P = 0.45). CONCLUSIONS Aortic bioprostheses are a good option for haemodialysis patients requiring AVR, offering acceptable mid-term survival. The Medtronic Freestyle aortic bioprostheses could allow the implantation of larger bioprostheses inferring consequently lower mean gradients, with a potentially higher resistance to calcification and sclerosis in haemodialysis patients.

Prediction and Perception of Technical Difficulties in Adult Cardiac Surgery

BACKGROUND Unexpected intra-operative technical difficulties are not uncommon in cardiac surgery. Our objective is to study the incidence, predictors, and consequences of unexpected difficulties in adult cardiac operations. METHODS A total of 500 consecutive elective operations were included in the study. Before every operation, the surgeon and the assistant were asked to study the case and give a score (one to ten) for the expected technical difficulty of the operation. After every operation, the surgeon and the assistant were asked to give a score for the observed technical difficulty. The scores and perioperative data were collected and statistically analyzed. RESULTS In relation to different interventions and consultant/trainee predictions, unexpected technical difficulties were encountered in 7% to 16% of cases. There was a significant difference between surgeons and trainees in the perception of level of increased difficulty, represented by the mean of differences between expected and observed score (0.084 ± 0.54 versus 0.016 ± 0.5, P = .0002). In multivariable analysis, only female gender (P < .0001) was identified as a factor associated with unexpected technical difficulties. There was no correlation between the incidence of complications and unexpected surgical difficulty. However, there was a weak positive correlation between operative times and observed difficulty score. CONCLUSION Unexpected technical difficulties are not uncommon in adult cardiac operations. Trainees tend to underestimate the difficulties perceived by the surgeon. This study can be a first step towards developing a technical difficulty score, which could be a helpful tool for medical quality management, as well as in training programs.

Congenital diaphragmatic hernia: unusual presentation in an adult.

Congenital abnormalities account to no more than 3% among live births. Among those, less than 0.003% involve the diaphragm. Congenital diaphragmatic hernias are mostly diagnosed early in life, later diagnosis is rare, especially if the hernia is asymptomatic. Foreign body ingestion is primarily an issue in pediatric medicine, with very rare adults ingesting foreign bodies, these adults are usually mentally impaired. We present a 26-year-old mentally intact patient, presenting to us with foreign body ingestion, that on chest radiographs and computerized tomography, prove to be residing in his intestines. The intestines are herniating into the left chest. To our knowledge, no similar case has been reported and published.

Impending rupture of the left atrium after impaction of left atrial ablation catheter.

A 60-year-old male presented with chronic atrial fibrillation. A trans-femoral catheter ablation was planned. The catheter was impacted in the left atrial wall (Fig. 1). Consequently, the procedure was interrupted before achieving resynchronisation. Catheter withdrawal was only possible after median sternotomy and closed manipulation of the catheter to release it.