Search

Patients who undergo coronary artery bypass graft (CABG) surgery in ischemic cardiomyopathy have a survival advantage over medical therapy at 10 years. The survival advantage of CABG over medical therapy is due to its ability to reduce future myocardial infarction, and by conferring electrical stability. The presence of myocardial viability does not provide a differential survival advantage for CABG over medical therapy. Presence of angina and inducible ischemia are also less predictive of outcome. Moreover, CABG is associated with significant early mortality. Hence, careful patient selection is more important for reducing the early mortality and improving the long-term outcome than relying on results of myocardial viability. Younger patients with good exercise tolerance benefit the most, while patients who are frail and patients with renal dysfunction and dysfunctional right ventricle seem to have very high operative mortality. Elderly patients, because of poor life expectancy, do not benefit from CABG, but the age cutoff is not clear. Patients also need to have revascularizable targets, but this decision is often based on experience of the surgical team and heart team discussion. These recommendations are irrespective of the myocardial viability tests. Optimal medical treatment remains the cornerstone for management of ischemic cardiomyopathy., Competing Interests: Conflict of interestThe authors declare no conflict of interest., (© Indian Association of Cardiovascular-Thoracic Surgeons 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

The role of surgery in infective endocarditis is becoming established the world over. In spite of all recent advances, endocarditis remains a lethal disease following surgery. With the emergence of more difficult-to-treat microorganisms, sicker and older patients with multiple co-morbidities, and an increase in healthcare-associated infections, the need for surgery in the management of infective endocarditis is only bound to increase. Data on the use of surgery in endocarditis till date is largely from observational data due to the relative rarity of the disease and variable practice patterns around the world. Hopefully, with increasing awareness and more inter-institutional and international collaborations, more robust data will emerge to further establish the role of surgery. For the time being, individual patient management will require the active multi-disciplinary approach of an endocarditis team to provide the best possible outcomes., Supplementary Information: The online version contains supplementary material available at 10.1007/s12055-023-01647-9., Competing Interests: Conflict of interestThe authors declare no conflict of interest., (© Indian Association of Cardiovascular-Thoracic Surgeons 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Background: Rheumatic fever and rheumatic heart disease is endemic in India. Mitral valve replacement with mechanical valve is the commonest surgical procedure performed in rheumatic heart disease (RHD). However, there are no studies reporting the long-term outcomes of mechanical mitral valve replacement in rheumatic heart disease from India., Objective: The primary objective of the study was to look at the long-term survival following mechanical mitral valve replacement in RHD. The secondary objectives included follow up complications and event-free survival., Methods: For this study, 238 patients who underwent mitral valve replacement with TTK Chitra™ valve from 1st January 2006 to 31st December 2018 for RHD were included for analysis and reporting. The median follow-up period was 3371.50 days (9.3 years). Total follow-up was 2044 patient-years., Results: The mean age of the study population was 39.72 ± 10.48 years (range: 18-68 years). Out of 238 patients operated, 155 patients (65.12%) were alive and 69 patients (28.99%) were dead, and 14 patients (5.88%) were lost to follow-up. The operative mortality was 6 (2.52%) and the follow-up mortality was 63 (26.47%). The reasons for follow-up mortality were cardiac complications in 22 (34.9%) patients, valve-related complications in 18 (28.5%) patients, sudden unexplained death in 13 (20.6%) patients, and non-valve/ non-cardiac death in 10patients (15.8%). The one-year survival was 94.0%, five-year survival was 83.6%, ten-year survival was 70.6% and 15-year survival was 62.9%. During follow-up, valve-related events occurred in 123(52%) patients. The 15-year event-free survival was 33.0%., Conclusions: The long term outcome of mechanical valve replacement of the mitral valve in RHD patients was less than favorable. Both cardiac complications and mechanical valve related complications reduced their survival., Competing Interests: Conflict of interestThe authors have no conflicts of interest to declare., (© Indian Association of Cardiovascular-Thoracic Surgeons 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Purpose: There has been debate whether off pump coronary artery bypass surgery (OPCAB) has results comparable to conventional on pump bypass surgery. This has led to the low uptake of OPCAB in the West. In India, OPCAB is the default mode of coronary revascularization. However, there is scarce data on mid-term outcomes of OPCAB in our patients. This study aims to evaluate both short and mid-term mortality and analyze factors associated with mortality., Methods: This is a single center study of all consecutive patients undergoing isolated OPCAB from October 2014 to December 2019. Patient data was collected from hospital records and follow-up was from the hospital electronic medical records and telephone interviews. Mortality and factors contributing to survival were analyzed., Results: Operative mortality was 2.3%. Mid-term mortality was 5.5%. Preoperative renal dysfunction, post-operative renal failure, use of the intra-aortic balloon pump (IABP), re-exploration for bleeding, postoperative stroke, ventilation > 24 h, and postoperative atrial fibrillation were associated with operative mortality. Factors associated with mid-term mortality were age > 62 years, postoperative renal failure, IABP usage, ventilation time > 24 h, and postoperative atrial fibrillation. The mean survival time was 2343.55 + / - 15.27 days and 6-year survival was 88.7%., Conclusion: OPCAB can safely be performed with satisfactory short and mid-term outcomes. Further corroborative studies from different regions of the country or a multi-center study will help to establish the suitability of the technique in Indian patients., Competing Interests: Conflict of interestThe authors declare no conflict of interest in relation to this manuscript., (© Indian Association of Cardiovascular-Thoracic Surgeons 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

This report highlights the outcome of valve replacement using TTK Chitra heart mechanical valve in a subgroup of pediatric patients This cohort of 27 pediatric patients with implantations during January 2006 to December 2018 was followed up prospectively. The cohort consisted of 12 aortic valve replacement (AVR), 14 mitral valve replacement (MVR), and 1 double valve replacement (DVR) patients. Total follow-up was 254 patient-years (AVR = 107, MVR = 136, DVR = 11) being 90% complete. The results show that the survival rates and event-free rates were satisfactory. Despite many reservations due to the high risk involved, the long-term benefits of having a durable valve replacement seem to outweigh the risks and offer acceptable long-term survival., Competing Interests: Conflict of interestDr. G. S. Bhuvaneswar reports receiving consultation fees from TTK Healthcare Limited on guidance provided for the company’s post-market clinical studies. The remaining authors have no conflicts of interest to declare., (© Indian Association of Cardiovascular-Thoracic Surgeons 2022, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Purpose: The TTK Chitra™ heart valve has more than 1,40,000 implantations so far, but no long-term data has been published. This study aims to provide long-term results of the valve., Methodology: A cohort of 476 patients with implantations from January 2006 to December 2018 were followed up prospectively consisting of 104 aortic valve replacement (AVR), 87 double valve replacement (DVR), and 285 mitral valve replacement (MVR) patients. Total follow-up was 4079 patient-years (py) (AVR = 983, MVR = 2392, DVR = 704), being 96% complete., Results: The results showed that actuarial survival at 15 years was 82.3% for AVR, 60.7% for MVR, and 52.2% for DVR. Freedom from all valve-related mortality and morbidity at 15 years was 73.8%, 64.8%, and 61.9% for AVR, MVR, and DVR, respectively. There was one instance of structural failure of valve disc leading to severe valvar regurgitation. Valve thrombosis incidence was 1 in AVR (0.1%/py), 6 in MVR (0.25%/py), and 1 in DVR (0.14%/py). Thrombo-embolic episodes occurred in 50 patients (AVR = 7 patients at 0.7%/py; MVR = 36 patients at 1.5%/py; DVR = 7 patients at 0.99%/py) and major hemorrhage (bleeding) in 24 patients (AVR = 0.61%/py; MVR = 0.5%/py; and DVR = 0.85%/py). The linearized rates of adverse events in this study were found to be lower than earlier published results., Conclusion: The results highlight the continued safety and performance of the TTK Chitra™ heart valve (TTKCHV) in the long term at 15 years., Supplementary Information: The online version contains supplementary material available at 10.1007/s12055-022-01437-9., Competing Interests: Conflict of interestDr. G. S. Bhuvaneshwar reports receiving consultation fees from TTK Healthcare Limited on guidance provided for the company’s post-market clinical studies. The remaining authors have no conflicts of interest to declare., (© The Author(s) 2022.)

In patients with a small aortic annulus, the clinical benefits of aortic valve replacement depend on avoidance of patient-prosthesis mismatch as it is associated with reduced overall survival. Aortic root widening or enlargement is a useful technique to implant larger valve prosthesis to prevent patient-prosthesis mismatch. Posterior annular enlargement is the commonest technique used for aortic root enlargement. Consistent enlargement of the aortic root requires more extensive procedures like Manouguian or Konno-Rastan techniques. The patients commonly selected are younger patients with good life expectancy. However, caution is advised in applying this procedure in elderly patients, patients with heavily calcified annulus and when performing concomitant procedures. There is no definitive conclusion on the best material to use for the reconstruction of aortic annulus and aorta in aortic root enlargement procedures., Competing Interests: Conflict of interestThe authors declare that they have no conflicts of interest., (© Indian Association of Cardiovascular-Thoracic Surgeons 2021.)

The single most important factor in improving outcomes in right ventricular (RV) failure is anticipating and recognizing it. Once established, a vicious circle of systemic hypotension, and RV ischemia and dilation, occurs, leading to cardiogenic shock, multi-organ failure, and death. RV dysfunction and failure theoretically can occur in three settings-increase in the pre-load; increase in after load; and decrease in contractility. For patients deemed low risk for the development of RV failure, when it occurs, the correction of underlying cause is the most important and effective treatment strategy. Therapy of RV failure must focus on improving the RV coronary perfusion, lowering pulmonary vascular resistance, and optimizing the pre-load. Pre-load and after-load optimization, ventilator adjustments, and improving the contractility of RV by inotropes are the first line of therapy and should be initiated early to prevent multi-organ damage. Mechanical assist device implantation or circulatory support with extracorporeal membrane oxygenation (ECMO) may be needed in refractory cases., Competing Interests: Conflict of interestThe authors declare no competing interests., (© Indian Association of Cardiovascular-Thoracic Surgeons 2021.)

Background: While the coronavirus disease 2019 (COVID-19) pandemic has affected all aspects of health care, its impact on cardiac surgical practice and outcomes is yet to be determined. We compared the outcomes of our cardiac surgical practice from the past year during the pandemic to those in a similar pre-pandemic period., Methods: Retrospective data were collected from 307 patients who were involved in all adult cardiac surgical procedures performed between March 2020 and February 2021, which was considered the pandemic period, at Amrita Institute of Medical Sciences, India. These were compared with data from the 1-year period between March 2019 and February 2020. During that earlier period, 491 patients underwent surgery, and the surgical outcomes were assessed. Outpatient visit data were also collected to evaluate the effect of COVID-19 on outpatient follow-up visits., Results: A 37% decrease in surgical case volume was observed during the study period. No difference was found in operative mortality between the 2 time periods (3.3% vs. 2.6%, p=0.383). Overall postoperative complications were less frequent during this period, at 23% compared to 38% the previous year (p<0.001)., Conclusion: The COVID-19 pandemic caused a dramatic decrease in surgical volume and outpatient medical follow-up. However, the pandemic and its attendant social restrictions did not yield a significant change in the surgical outcomes of our patients. Hence, it is reasonable to continue cardiac surgical care during global health crises, and this can be done with good results.

Trans-aortic septal myectomy is the gold standard for septal reduction therapy. This technique has low peri-procedural mortality and excellent long-term survival. Moreover, it relieves the heart failure symptoms and improves the quality of life. Secondary chordal cutting along with septal myectomy has shown to improve the outcome but can potentially cause deterioration of left ventricular function. In patients with relatively thin inter-ventricular septum, abnormalities of mitral valve apparatus may be the main reason for systolic anterior motion and left ventricular outflow tract obstruction. These patients may require additional procedures on the mitral valve to shift the coaptation plane away from outflow tract. Mitral valve replacement should be performed only in patients with intrinsic mitral valve abnormalities that are not suitable for repair and its routine use along with limited septal myectomy should be discouraged. Minimal access surgery although attractive in concept requires more robust data before universal application.

Right ventricle (RV) dysfunction and failure are now increasingly recognized as an important cause of perioperative morbidity and mortality after cardiac surgery. Although RV dysfunction is common, RV failure is very rare (0.1%) after routine cardiac surgery. However, it occurs in 3% of patients after heart transplantation and in up to 30% of patients after left ventricular assist device implantation. Significant RV failure after cardiac surgery has high mortality. Knowledge of RV anatomy and physiology are important for understanding RV dysfunction and failure. Echocardiography and haemodynamic monitoring are the mainstays in the diagnosis of RV dysfunction and failure. While detailed echocardiography assessment of right heart function has been extensively studied and validated in the elective setting, gross estimation of RV chamber size, function, and some easily obtained quantitative parameters on transesophageal echocardiography are useful in the perioperative setting. However, detailed knowledge of echocardiography parameters is still useful in understanding the differences in contractile pattern, ventriculo-arterial coupling, and interventricular dependence that ensue after open cardiac surgery., Supplementary Information: The online version contains supplementary material available at 10.1007/s12055-021-01240-y., Competing Interests: Conflict of interestThe authors declare no competing interests., (© Indian Association of Cardiovascular-Thoracic Surgeons 2021.)

Purpose: Despite advances in medical care, infective endocarditis (IE) has high mortality. Surgery for IE though recommended for complications of the disease is still not commonly offered due to conflicting reports in the literature. We reviewed our results of surgery for IE from the last 5 years to assess their outcome., Methods: A retrospective review from a single center of consecutive patients who underwent surgery for infective endocarditis from September 2014 to December 2019 was done. Data was collected from hospital records and follow-up done up to May 2020. Outcomes evaluated were mortality, follow-up survival, and postoperative complications. Factors affecting mortality and survival were analyzed., Results: Ninety-seven patients underwent surgery for IE during this period. Seventy-nine had native valve endocarditis (NVE) and 18 had prosthetic valve endocarditis (PVE). The overall postoperative mortality was 13%, with mortality for native valve endocarditis being 11% and that for prosthetic valve endocarditis being 22%, which was not statistically significant. Three-year survival for the overall group was 88.7% with 88.1% for NVE and 91.7% for PVE. Multivariate predictors of operative mortality were a high EuroSCORE II, diabetes mellitus, and the presence of Staphylococcus organism., Conclusion: Surgery for infective endocarditis has a very acceptable early outcome and intermediate-term survival., Competing Interests: Conflict of interestThe authors declare that they have no conflicts of interest., (© Indian Association of Cardiovascular-Thoracic Surgeons 2021.)

Purpose: Ticagrelor combined with aspirin had shown better saphenous vein graft patency than aspirin with clopidogrel after off-pump coronary artery bypass grafting. However, the safety of this drug in regard to bleeding complications remains unknown. The aim of our study was to assess the bleeding complications of dual antiplatelet therapy with aspirin and ticagrelor compared with aspirin and clopidogrel within the first 3 months after off-pump surgery., Methods: Three hundred eighty-two consecutive patients who were prescribed aspirin with ticagrelor (ticagrelor group) were compared with 660 patients who received aspirin and clopidogrel (clopidogrel group). After propensity matching, 144 patients in each group were compared for bleeding events and major adverse cardiac and cerebral events. Major bleeding was defined as composite outcome of re-exploration for bleeding, any fatal bleeding, intracranial bleeding, and any bleeding requiring hospitalization., Results: Patients in the ticagrelor group had more incidence of re-exploration for bleeding ( p  = 0.042), pericardial effusion requiring drainage ( p  = 0.007), readmissions ( p  < 0.01), gastrointestinal bleeding ( p  = 0.01), and major bleeding (5.8% vs. 2.1%, p  < 0.01, OR 2.8 (1.43-5.58)). After propensity analysis, gastrointestinal bleed ( p  = 0.024), major bleeding (7.6% vs.1.4%, p  < 0.001, OR 5.8 (1.28-26.97)), length of ICU stay ( p  = 0.039), and readmissions ( p  = 0.003, OR 11.83 (1.51-92.86)) were more in the ticagrelor group. Major adverse cardiac and cerebral events were similar between the groups., Conclusion: Dual antiplatelet therapy with aspirin and ticagrelor increased gastrointestinal bleeding events, major bleeding events, and readmission rates compared with aspirin and clopidogrel after off-pump coronary artery bypass grafting., Competing Interests: Conflict of interestThe authors declare that they have no conflicts of interest., (© Indian Association of Cardiovascular-Thoracic Surgeons 2020.)

Objective: Post-operative atrial fibrillation (POAF) increases hospital stay, resource utilization, morbidity, and mortality. However, there is paucity of data about its effect in Indian patients undergoing off-pump coronary artery bypass grafting (CABG)., Methods: Seven hundred forty-eight patients underwent off-pump CABG from January 2015 to December 2016 (24 months). One hundred twenty-seven patients (16.7%) developed POAF. In an effort to mitigate the effects of wider risk factors on perioperative outcomes, a separate sub-analysis of patients based on risks quantified by EuroSCORE II (<> 3) was also performed., Results: Age > 60 years and development of sepsis were the independent predictors for the development of POAF. Thirty-day/mortality rate was higher in the POAF group (7.1% vs. 1.4%; p value < 0.001). POAF was associated with increased ICU and hospital stay and increased incidence of stroke and renal dysfunction. The survival was significantly lower in the POAF group compared with the normal sinus rhythm (NSR) (3-year survival in POAF was 81.3% vs. 94.4% in the NSR group; Hazard ratio (HR) 3.867 (1.989-7.516)). Intra-aortic balloon pump (IABP) usage, age ≥ 60 years and sepsis were independent predictors for the development of POAF in low-risk patients. For the NSR group, 1-year survival was 98% and 3-year survival was 95.7%. For the POAF group, 1-year survival was 94.4% and 3-year survival was 84.0% (HR. 3.794 (1.897-7.591))., Conclusion: The incidence of POAF was lower than reported in the wider global literature. Increasing age and development of post-operative sepsis were strong independent predictors of POAF. POAF increases the morbidity; length of hospital stay and these patients show decreased survival after off-pump CABG., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Indian Association of Cardiovascular-Thoracic Surgeons 2019.)

Background Many observational studies and trials have shown that coronary artery bypass grafting improves the survival in patients with ischemic cardiomyopathy. However, these results are based on data generated from developed countries. Poor socioeconomic statuses, lack of uniformity in healthcare delivery, differences in risk profile, and affordability to access optimal health care are some factors that make the conclusions from these studies irrelevant to patients from India. Methods and Results One-hundred and sixty-two patients with severe left ventricular dysfunction (ejection fraction ≤35%) who underwent coronary artery bypass grafting from 2009 to 2017 were enrolled for this study. Mean age of the study population was 58.67±9.70 years. Operative mortality was 11.62%. Thirty day/in-house composite outcome of stroke and perioperative myocardial infarction were 5.8%. The percentage of survival for 1 year was 86.6%, and 5-year survival was 79.9%. Five-year event-free survival was 49.3%. The mean ejection fraction improved from 30.7±4.08% (range 18-35) to 39.9±8.3% (range 24-60). Lack of improvement of left ventricular function was a strong predictor of late mortality (hazard ratio, 21.41; CI 4.33-105.95). Even though there was a trend towards better early outcome in off-pump CABG , the 5-year survival rates were similar in off-pump and on-pump group (73.4% and 78.9%, respectively; P value 0.356). Conclusions We showed that coronary artery bypass grafting in ischemic cardiomyopathy was associated with high early composite outcomes. However, the 5-year survival rates were good. Lack of improvement of left ventricular function was a strong predictor of late mortality.

Background: In spite of general decline worldwide, off-pump coronary artery bypass grafting (CABG) surgery is performed in more than 60% of patients undergoing CABG in India; mainly because of shorter operative time and reduced procedure cost. However, paucity of data exists in literature about early outcomes following off-pump CABG from India., Methodology: We conducted a prospective observational study of 800 consecutive cases that underwent off-pump CABG (OPCAB) from August 2015 to October 2017. Primary end point of the study was the 30-day/in-hospital mortality from any cause., Results: On multivariate analysis, emergency surgery (OR 9.72; CI 1.96-48.21, p value 0.005), severe left ventricular dysfunction (OR 2.28; CI 1.25-4.76, p value 0.026), postoperative atrial fibrillation (OR 9.95; CI 3.12-32.01, p value 0.05), and dialysis-dependent renal failure (OR 29.7, CI 10.02-87.99, p value 0.006) were the factors associated with mortality. The observed mortality was 1.6%, and the expected mortality by EuroSCORE II was 2.6%. The median EuroSCORE II of expired patients was 3.03 and of entire cohort was 1.54 ( p value 0.001). Stroke rate was 0.9%. Deep sternal wound infection occurred in 0.9%, and 3.8% patients were readmitted to the hospital after discharge., Conclusion: Early outcome of off-pump CABG was excellent in this study. Increased incidence of deep sternal wound infection remains a concern. Multicenter study with a larger sample size is required for a dependable evaluation of the efficacy of off-pump CABG in Indian population., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Indian Association of Cardiovascular-Thoracic Surgeons 2018.)

Background: The female gender is considered as a risk factor for morbidity and mortality after coronary artery bypass grafting (CABG)., Aim: In this analysis, we assessed the impact of female gender on early outcome after CABG., Study Design: This is a retrospective analysis of data from our center situated in South India., Statistical Analysis: Patients were categorized according to gender and potential differences in pre-operative and post-operative factors were explored. Significant risk factors were then built in a multivariate model to account for differences in predicting gender influence on surgical outcome., Methods: 773 consecutive patients underwent first time CABG between January 2015 and December 2016. 96.77% of cases were performed using off-pump technique. 132 (17.07%) patients were females. These patients formed the study group., Results: The in-house/ 30-day mortality in females was similar to that of males (3.03% vs. 3.12%, p value 0.957). Mediastinitis developed more commonly in females (5.35% vs. 1.30%; p value 0.004) compared to males. There were more re-admissions to hospital for female patients (21.37% in females vs. 10.14% in males, p value <0.001). In multivariate analysis using logistic regression; there was a significant association between age (OR 1.08), chronic obstructive airway disease (OR 4.315), and use of therapeutic antibiotics (OR 6.299), IABP usage (OR 11.18) and renal failure requiring dialysis (OR 28.939) with mortality., Conclusions: Early mortality in females was similar to that of males. Females were associated with higher rate of wound infection and readmission to hospital.

Competing Interests: There are no conflicts of interest

Anomalies of the mitral valve apparatus in hypertrophic cardiomyopathy are an important cause of systolic anterior motion. Patients with significant residual obstruction due to systolic anterior motion after myectomy and anterior mitral leaflet plication may end up having mitral valve replacement. We describe the case of a 52-year-old man who underwent posterior mitral leaflet plication to correct residual systolic anterior motion after anterior mitral leaflet plication.

Ischemic mitral regurgitation (IMR) is a frequent complication of left ventricular (LV) global or regional pathological remodeling due to chronic coronary artery disease. It is not a valve disease but represents the valvular consequences of increased tethering forces and reduced closing forces. IMR is defined as mitral regurgitation caused by chronic changes of LV structure and function due to ischemic heart disease and it worsens the prognosis. In this review, we discuss on etiology, pathophysiology, and mechanisms of IMR, its classification, evaluation, and therapeutic corrective methods of IMR.

Primary percutaneous transluminal coronary angioplasty (PTCA) with the insertion of a stent is a well-established procedure for management of coronary artery disease. Infected pseudoaneurysms following PTCA and stenting are very rare and have poor outcomes if not managed properly. We are presenting a case of a man aged 50 years with infected pseudoaneurysm of the left anterior descending artery following multiple percutaneous interventions for coronary artery disease. In this paper, we have described the presentation, diagnosis and management of this patient and have discussed the aetiology and management options of infected pseudoaneurysm affecting coronary arteries., Competing Interests: Conflicts of Interest: None declared., (2016 BMJ Publishing Group Ltd.)

Superior vena cava syndrome is one of the rare adverse events associated with pacemaker leads. We describe a 47-year-old woman with a pacemaker implanted 10 years earlier who presented to us with superior vena cava syndrome managed surgically. We report the presentation, diagnosis, and treatment of this patient and the causes and management options of superior vena cava obstruction associated with pacemaker leads., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Helices, strands and coils in proteins of known three-dimensional structure, corresponding to heptapeptide and large sequences ('probe' peptides), were scanned against peptide sequences of variable length, comprising seven or more residues that correspond to a different conformation ('target' peptides) in protein crystal structures available from the Protein Data Bank (PDB). Where the 'probe' and 'target' peptide sequences exactly match, they correspond to 'chameleon' sequences in protein structures. We observed ∼548 heptapeptide and large chameleon sequences that included peptides in the coil conformation from 53,794 PDB files that were analyzed. However, after excluding several chameleon peptides based on the quality of protein structure data, redundancy and peptides associated with cloning artifacts, such as, histidine-tags, we observed only ten chameleon peptides in structurally different proteins and the maximum length comprised seven amino acid residues. Our analysis suggests that the quality of protein structure data is important for identifying possibly, the 'true chameleons' in PDB. Majority of the chameleon sequences correspond to an entire strand in one protein that is observed as part of helix sequence in another protein. The heptapeptide chameleons are characterized with a high propensity of alanine, leucine and valine amino acid residues. The total hydropathy values range between -11.2 and 22.9, the difference in solvent accessibility between 2.0 Å(2) and 373 Å(2) units and the difference in total number of residue neighbor contacts between 0 and 7 residues. Our work identifies for the first time heptapeptide and large sequences that correspond to a single complete helix, strand or coil, which adopt entirely different secondary structures in another protein., (Copyright © 2011 Elsevier B.V. All rights reserved.)