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Anomalies of coronary venous system, the valve of the coronary sinus (Thebesian valve) and other cardiac malformations may make interventions through the coronary sinus difficult. These variants may pose a challenge in cannulating the coronary sinus for retrograde cardioplegia and for interventions performed through the coronary sinus by cardiac electrophysiologist/interventional cardiologist. Retrograde cardioplegia is an established method of myocardial protection with advantages, indications, and complications. A good knowledge of the anatomy of the coronary sinus and its variants is important in understanding the difficulties encountered while cannulating the coronary sinus for the delivery of retrograde cardioplegia, cardiac resynchronization therapy, treatment of arrhythmias, and percutaneous mitral valve annuloplasty., (© 2024 American Association of Clinical Anatomists and British Association of Clinical Anatomists.)

Strut chordae, on their own, are not typically thought to aid mitral valve competence. The aim of this study is to assess whether strut chordae aid mitral valve competence during acute annular dilation. Twelve porcine hearts were dissected and tested using an in vitro simulator, with the mitral annulus tested in either a 'normal' or a dilated configuration. The normal configuration included a diameter of 30 mm, a posterior leaflet 'radius' of 15 mm and a commissural corner 'radius' of 7.5 mm; the dilated annular template instead used dimensions of 50 mm, 25 mm and 12.5 mm, respectively. Each mitral valve underwent ten repeat tests with a target systolic pressure of 100 mmHg. No significant difference in the pressure was detected between the dilated and regular annuli for the mitral valves tested (95 ± 3 mmHg cf. 95 ± 2 mmHg). However, the volume of regurgitation for a dilated annulus was 28 ml greater than for a valve with a normal annulus. Following severing of strut chordae, there was a significant reduction in the systolic pressure withstood before regurgitation by mitral valves with dilated annuli (60 ± 29 mmHg cf. 95 ± 2 mmHg for normal annular dimensions; p < 0.05). In conclusion, strut chordae tendineae may play a role in aiding mitral valve competence during pathophysiology.

The aim of this study was to assess whether the mechanical properties of mitral valve chordae tendineae are sensitive to being cross-linked under load. A total 64 chordae were extracted from eight porcine hearts. Two chordae (posterior basal) from each heart were subjected to uniaxial ramp testing and six chordae (two strut, two anterior basal and two posterior basal) were subjected to dynamic mechanical analysis over frequencies between 0.5 and 10 Hz. Chordae were either cross-linked in tension or cross-linked in the absence of loading. Chordae cross-linked under load transitioned from high to low extension at a lower strain than cross-linked unloaded chordae (0.07 cf. 0.22), with greater pre-transitional (30.8 MPa cf. 5.78 MPa) and post-transitional (139 MPa cf. 74.1 MPa) moduli. The mean storage modulus of anterior strut chordae ranged from 48 to 54 MPa for cross-linked unloaded chordae, as compared to 53-61 MPa cross-linked loaded chordae. The mean loss modulus of anterior strut chordae ranged from 2.3 to 2.9 MPa for cross-linked unloaded chordae, as compared to 3.8-4.8 MPa cross-linked loaded chordae. The elastic and viscoelastic properties of chordae following glutaraldehyde cross-linking are dependent on the inclusion/exclusion of loading during the cross-linking process; with loading increasing the magnitude of the material properties measured.

The aim of this study was to perform an initial assessment, in vitro, of the feasibility of using a glutaraldehyde cross-linked porcine mitral valve to retain acute functionality, focusing on assessing mitral regurgitation. Six porcine hearts were tested using an in vitro simulator. Testing was repeated following cross-linking of mitral valves; where cross-linking was achieved by placing them in a glutaraldehyde solution. The simulator enabled systolic pressure on the ventricular side of the valve to be mimicked. Following testing, mitral valve leaflets underwent Scanning Electron Microscopy of the ventricular surface of both the anterior and posterior leaflets (1 cm 2 samples). The peak pressure withstood by cross-linked valves was significantly lower than for untreated valves (108 mmHg cf. 128 mmHg for untreated valves; p   < 0.05). The peak pressure was typically reached 0.5 s later than for the untreated valve. While both cross-linked and untreated valves exhibited endothelium denudation, the unfixed valve had less endothelial loss. Glutaraldehyde cross-linking of porcine mitral valves may be of potential value in assessing improved bioprosthetic mitral valve replacements. However, a more immobile valve exhibiting endothelial denudation (i.e. sclerosis) was a possible concerns identified following in vitro acute assessment.

Background: Mitral valve failure can require repair or replacement. Replacement bioprosthetic valves are treated with glutaraldehyde prior to implantation. The aim of this study was to determine the changes in mechanical properties following glutaraldehyde fixation of mitral valve chordae., Methods: To investigate the impact of glutaraldehyde on mitral valve chordae, 24 basal chordae were dissected from four porcine hearts. Anterior and posterior basal (including strut) chordae were used. All 24 chordae were subjected to a sinusoidally varying load (mean level 2N, dynamic amplitude 2N) over a frequency range of 0.5-10 Hz before and after glutaraldehyde treatment., Results: The storage and loss modulus of all chordal types decreased following glutaraldehyde fixation. The storage modulus ranged from: 108 to 119 MPa before fixation and 67.3-87.4 MPa following fixation for basal chordae; 52.3-58.4 MPa before fixation and 47.9-53.5 MPa following fixation for strut chordae. Similarly, the loss modulus ranged from: 5.47 to 6.25 MPa before fixation and 3.63-4.94 MPa following fixation for basal chordae; 2.60-2.97 MPa before fixation and 2.31-2.93 MPa following fixation for strut chordae., Conclusion: The viscoelastic properties of mitral valve chordae are affected by glutaraldehyde fixation; in particular, the reduction in storage moduli decreased with an increase in chordal diameter.

The aim of this study was to determine the regional variation in viscoelastic properties of mitral valve leaflets over a range of physiological and patho-physiological frequencies. This included comparisons to be made between anterior and posterior leaflets, anterior leaflet clear and rough zones, and radial and circumferential leaflet orientation. Dynamic mechanical analysis was used to determine frequency-dependent viscoelastic properties. The valve leaflets were dissected from eight porcine hearts. The leaflets were loaded under a sinusoidal tensile displacement, with a mean dynamic peak to trough strain of 11%, applied to all leaflet samples at nine different frequencies, ranging from 0.5 to 10 Hz. The anterior leaflet has higher storage and loss stiffness than the posterior leaflet. The storage stiffness of circumferential tissue is greater than that of radially oriented valve tissue (2.0 ± 1.6 N/mm cf. 1.7 ± 0.9 N/mm; p < 0.05); however, the loss stiffness is greater for radial tissue (0.15 ± 0.07 cf. 0.14 ± 0.09 N/mm; p < 0.05). Likewise, the storage stiffness of the anterior leaflet clear zone is greater than that of the rough zone (2.4 ± 1.6 cf. 2.1 ± 1.2; p < 0.05), but the loss stiffness is greater for the rough zone (0.17 ± 0.09 N/mm cf. 0.14 ± 0.08 N/mm; p < 0.05). In conclusion, the viscoelastic properties of porcine mitral valve leaflets have regional variations, with dynamic stiffness being dependent on circumferential or radial orientation and on location at a clear or rough zones.

This study aimed to characterise viscoelastic properties of different categories of chordae tendineae over a range of frequencies. Dynamic Mechanical Analysis (DMA) was performed using a materials testing machine. Chordae (n=51) were dissected from seven porcine hearts and categorised as basal, marginal, strut or commissural. Chordae were loaded under a sinusoidally varying tensile load at a range of frequencies between 0.5 and 5Hz, both at a standardised load (i.e. same mean load of 4N for all chordae) and under chordal specific loading (i.e. based on in vivo loads for different chordae). Storage modulus and stiffness were frequency-dependent. Loss modulus and stiffness were frequency-independent. Storage and loss moduli, but not stiffness, decreased with chordal diameter. Therefore, strut chordae have the lowest moduli and marginal chordae the highest moduli. The hierarchy of dynamic storage and loss moduli is: marginal, commissural, basal and strut. In conclusion, viscoelastic properties of chordae are dependent on both frequency and chordal type. Future/novel replacement chordal materials should account for frequency and diameter dependent viscoelastic properties of chordae tendineae., (© 2013 Published by Elsevier Ltd.)

A 72-year-old man who had undergone a three-vessel coronary artery bypass grafting, aortic valve replacement, and tricuspid valve repair became comatose 1 week after the procedure. Signs of intraabdominal sepsis developed 6 days later, leading to laparotomy on his 12th postoperative day. The Intraoperative finding was a perforating injury to the transverse colon caused by the ventricular temporary pacing wires. A defunctioning double-barreled transverse colostomy was performed, after which the patient started to recover. He was discharged home 2 weeks later., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Repair of the mitral valve is defined (loosely) as a procedure that alters the valve structure, without replacement, enabling the natural valve itself to continue to perform under the physical conditions to which it is exposed. As the mitral valve is driven by flow and pressure, it should be feasible to analyse and assess its function, failure and repair as a mechanical system. This article reviews the current state of mechanical evaluation of surgical repairs of the failed mitral valve of the heart. This review describes the anatomy and physiology of the mitral valve, followed by the failure of the mitral valve from a mechanical point of view. The surgical methods used to repair failed valves are introduced, while the use of engineering analysis to aid understanding of mitral valve repair is also reviewed. Finally, a section on recommendations for development and future uses of engineering techniques to surgical repair are presented.

The neutrophil/lymphocyte (N/L) ratio integrates information on the inflammatory milieu and physiologic stress. It is an emerging marker of prognosis in patients with cardiovascular disease. We investigated the relation between the N/L ratio and postoperative atrial fibrillation (AF) in patients undergoing coronary artery bypass grafting. In a prospective cohort study, 275 patients undergoing nonemergency coronary artery bypass grafting were recruited. Patients with previous atrial arrhythmia or requiring concomitant valve surgery were excluded. The N/L ratio was determined preoperatively and on postoperative day 2. The study end point was AF lasting >30 seconds. Patients who developed AF (n = 107, 39%) had had a greater preoperative N/L ratio (median 3.0 vs 2.4, p = 0.001), but no differences were found in the other white blood cell parameters or C-reactive protein. The postoperative N/L ratio was greater in patients with AF (day 2, median 9.2 vs 7.2, p <0.001), and in multivariate models, a greater postoperative N/L ratio was independently associated with a greater incidence of AF (odds ratio 1.10 per unit increase, p = 0.003: odds ratio for N/L ratio >10.14 [optimal postoperative cutoff in our cohort], 2.83 per unit, p <0.001). Elevated pre- and postoperative N/L ratios were associated with an increased occurrence of AF after coronary artery bypass grafting. In conclusion, these results support an inflammatory etiology in postoperative AF but suggest that other factors are also important., (Copyright 2010 Elsevier Inc. All rights reserved.)

Background: N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a powerful predictor of cardiovascular outcome in many circumstances. There are, however, limited data regarding the utility of NT-proBNP or BNP levels in patients undergoing cardiac surgery. The current study assesses the ability of NT-proBNP to predict early outcome in this setting., Methods: One thousand and ten patients undergoing non-emergent cardiac surgery were recruited prospectively. Baseline clinical details were obtained and the European System for Cardiac Operative Risk Evaluation (EuroSCORE) and Parsonnet score were calculated. Preoperative NT-proBNP levels were measured using the Roche Elecsys assay. The primary endpoint was 30 day mortality., Results: Median NT-proBNP levels were 624 ng litre(-1) among patients who died within 30 days of surgery (n=29), compared with 279 ng litre(-1) in survivors [odds ratio (OR) 1.03 per 250 ng litre(-1), 95% confidence interval 1.01-1.05, P=0.001). NT-proBNP levels remained predictors of 30 day mortality in models including either the additive EuroSCORE (OR 1.03 per 250 ng litre(-1), P=0.01), the logistic EuroSCORE (OR 1.03 per 250 ng litre(-1), P=0.004), or the Parsonnet score (OR 1.02 per 250 ng litre(-1), P=0.04). Levels of NT-proBNP were also predictors of prolonged (>1 day) stay in the intensive care unit (OR 1.03 per 250 ng litre(-1), P<0.001) and of a hospital stay >1 week (OR 1.07 per 250 ng litre(-1), P<0.001). They remained predictive of these outcomes in regression models that included either the EuroSCORE or the Parsonnet score and in a model that included all study variables., Conclusions: NT-proBNP levels predict early outcome after cardiac surgery. Their prognostic utility is modest-but is independent of traditional indicators and conventional risk prediction scores.

Background: Atrial fibrillation (AF) is a common complication after coronary artery bypass grafting (CABG). We prospectively compared the ability of echocardiographic parameters and the cardiac neurohormones, brain natriuretic peptide (BNP), and N-terminal pro-brain natriuretic peptide (NT-proBNP) to predict AF in this setting., Methods: We recruited 275 patients undergoing nonemergency CABG. Patients undergoing valve surgery or with prior atrial dysrhythmia (based on clinical history and review of medical records) were excluded. Echocardiography was performed, and natriuretic peptide levels were measured, 24 hours before surgery. The primary end point was postoperative AF lasting >30 seconds., Results: The only significant echocardiographic predictors of postoperative AF (n = 107, 39%) were the transmitral E to A-wave ratio and the early mitral annulus velocity. Levels of BNP and NT-proBNP were higher in patients who developed AF. Both natriuretic peptides, but none of the echocardiographic parameters, remained independently predictive in multivariable analysis. The optimum cut points for predicting AF were 31 pg/mL for BNP (odds ratio [OR] 2.74, P = .001) and 74 pg/mL for NT-proBNP (OR 2.74, P = .003)., Conclusion: Levels of BNP and NT-proBNP are independent, though modestly effective, predictors of AF after isolated CABG. In contrast, none of the echocardiographic parameters assessed, including measures of LV systolic function and filling pressure, were independently predictive.

Objective: Elevated uric acid levels have been associated with an adverse cardiovascular outcome in several settings. Their utility in patients undergoing surgical revascularization has not, however, been assessed. We hypothesized that serum uric acid levels would predict the outcome of patients undergoing coronary artery bypass grafting., Methods: The study cohort consisted of 1140 consecutive patients undergoing nonemergency coronary artery bypass grafting. Clinical details were obtained prospectively, and serum uric acid was measured a median of 1 day before surgery. The primary end point was all-cause mortality., Results: During a median of 4.5 years, 126 patients (11%) died. Mean (+/- standard deviation) uric acid levels were 390 +/- 131 micromol/L in patients who died versus 353 +/- 86 micromol/L among survivors (hazard ratio 1.48 per 100 micromol/L; 95% confidence interval, 1.25-1.74; P < .001). The excess risk associated with an elevated uric acid was particularly evident among patients in the upper quartile (>or=410 micromol/L; hazard ratio vs all other quartiles combined 2.18; 95% confidence interval, 1.53-3.11; P < .001). After adjusting for other potential prognostic variables, including the European System for Cardiac Operative Risk Evaluation, uric acid remained predictive of outcome., Conclusion: Increasing levels of uric acid are associated with poorer survival after coronary artery bypass grafting. Their prognostic utility is independent of other recognized risk factors, including the European System for Cardiac Operative Risk Evaluation.

Objective: To determine the effects of socio-economic status (SES) on the outcome of coronary artery bypass grafting (CABG)., Design: Prospective cohort study., Setting: Regional cardiac surgical unit., Patients: 1994 consecutive patients undergoing non-emergency CABG., Measures: SES was determined from the patient's postcode using Carstairs tables. The primary end-point was all-cause mortality at 30 days., Results: There were 50 deaths (2.5%) within 30 days of surgery. A higher Carstairs score demonstrated a trend towards increased 30-day mortality (odds ratio (OR) 1.09 per unit, 95% CI 1.00 to 1.20, p = 0.06). In a backward conditional model, including other predictors of early mortality, Carstairs scores were independently predictive (OR 1.12 per unit, 95% CI 1.01 to 1.24, p = 0.02). In a model including only Carstairs scores and the EuroSCORE, both were independent predictors of this outcome (OR for Carstairs score 1.11 per unit, 95% CI 1.00 to 1.22, p = 0.04). The 30-day mortality increases in each quartile of Carstairs scores, with patients in quartile 4 (most deprived) at significantly higher risk compared with quartile 1 (uncorrected OR 2.53 per unit, 95% CI 1.04 to 6.15; OR corrected for EuroSCORE, 2.56 per unit, 95% CI 1.03 to 6.34, p = 0.04 for both). Similarly, patients in the least affluent quartile were twice as likely to suffer a serious complication as those in the most affluent quartile (OR 2.14 per unit, 95% CI 1.32 to 3.46, p = 0.002). This increased risk was also independent of the EuroSCORE., Conclusions: Lower SES is associated with a poorer early outcome following CABG and is independent of other recognised risk factors.

Background: The prognostic importance of renal function in patients undergoing surgery for valvular heart disease is poorly defined. The current study addresses this issue., Methods: Baseline demographic and clinical variables, including the European system for cardiac operative risk evaluation (EuroSCORE), were recorded prospectively from 514 consecutive patients undergoing heart valve surgery between April 2000 and March 2004. Patients with active infective endocarditis and/or requiring emergency surgery were excluded. The glomerular filtration rate was estimated (eGFR) using the Modification of Diet in Renal Disease equation. The primary outcome was all-cause mortality., Results: During a median follow-up of 2 years, 87 patients died. In univariable analysis, both eGFR (hazard ratio [HR] 0.69 per 10 mL/min per 1.73 m2, P<.001) and creatinine (HR 1.04 per 10 micromol/L, P<.001) predicted mortality. Estimated GFR was a stronger predictor and was used in subsequent multivariable models. It remained a powerful independent predictor of death in a multivariable model including all study variables (HR 0.70 per 10 mL/min per 1.73 m2 increase, P<.001) and in a model including EuroSCORE (HR 0.64 per 10 mL/min per 1.73 m2 increase, P<.001). After correction for preoperative EuroSCORE, an eGFR of <60 mL/min per 1.73 m2 was associated with an excess hazard of death of 2.31 (P=.001)., Conclusion: Renal function, particularly the eGFR, is a powerful predictor of outcome in patients undergoing heart valve surgery. This prognostic utility is independent of other recognized risk factors and the EuroSCORE.

Background: An elevated preoperative white blood cell count has been associated with a worse outcome after coronary artery bypass grafting (CABG). Leukocyte subtypes, and particularly the neutrophil-lymphocyte (N/L) ratio, may however, convey superior prognostic information. We hypothesized that the N/L ratio would predict the outcome of patients undergoing surgical revascularization., Methods: Baseline clinical details were obtained prospectively in 1938 patients undergoing CABG. The differential leukocyte was measured before surgery, and patients were followed-up 3.6 years later. The primary end point was all-cause mortality., Results: The preoperative N/L ratio was a powerful univariable predictor of mortality (hazard ratio [HR] 1.13 per unit, P < .001). In a backward conditional model, including all study variables, it remained a strong predictor (HR 1.09 per unit, P = .004). In a further model, including the European system for cardiac operative risk evaluation, the N/L ratio remained an independent predictor (HR 1.08 per unit, P = .008). Likewise, it was an independent predictor of cardiovascular mortality and predicted death in the subgroup of patients with a normal white blood cell count. This excess hazard was concentrated in patients with an N/L ratio in the upper quartile (>3.36)., Conclusion: An elevated N/L ratio is associated with a poorer survival after CABG. This prognostic utility is independent of other recognized risk factors.

The aim of the investigation was to vary certain geometrical features of the mitral valve in vitro, in order to understand their role in valve function. Geometrical changes to mitral valve components are known to affect valve function, but complete understanding of how geometrical changes influence valve function is far from complete. Test apparatus has been used to apply pressure to porcine mitral valves. Porcine mitral valve specimens were tested both in their intact state and with a specific aspect of their geometry altered. The geometric parameters of the mitral valve varied were (1) the length between the papillary muscles and the mitral annulus (termed the annulo-papillary length), (2) the diameter of the left ventricle at the level of the papillary muscles, and (3) the mitral annular area. Six specimens were tested for each parameter investigated. A minimum annulo-papillary length was necessary to allow chordae tendineae to pull on the valve leaflets in order to prevent mitral valve failure; increasing this length further improved valve closure. Over the experimental range tested, left ventricular dilation at the level of the papillary muscles did not induce failure (P not significant). Increasing the mitral annular area was found to induce failure (P = 0.030 and P = 0.018 for medium and large annular diameters, respectively). The results demonstrate the importance of the geometry of mitral valve components on its function, and give insights into further experiments required to provide further understanding of the role of mitral valve geometry in its function. The results demonstrate that this in vitro method can be used to vary selected features of the geometry of the mitral valve.

A case of primary malignant melanoma in the mediastinum presenting as recurrent laryngeal nerve palsy is reported. Tissue biopsy at mediastinotomy yielded a diagnosis of malignant melanoma. The mass was fixed to the left aspect of the trachea and to the upper border of the left main bronchus and could not be removed surgically. Further extensive clinical and radiological investigations revealed no evidence of tumor elsewhere in the body.

Background and Aim of the Study: The study aim was to compare mitral valve repair techniques in vitro. Rupture or elongation of the mitral valve chordae tendineae is a known cause of mitral regurgitation, and can be corrected by edge-to-edge repair, chordal replacement, or chordal transposition., Methods: A test apparatus was used to apply pressure to porcine mitral valves. Mitral valve specimens were tested intact (n = 50), after they had been experimentally damaged, and after repair. Each test was repeated ten times. Experimental damage consisted of severing either the anterior leaflet strut, and attached marginal chordae (n = 30) or posterior leaflet chordae (n = 20). Valves with damaged anterior leaflets were repaired by either: (i) edge-to-edge repair; (ii) chordal replacement; or (iii) chordal transposition. Valves with damaged posterior leaflets were repaired by the first two techniques. Each repair method was repeated on ten specimens., Results: Mitral valves repaired using the edge-to-edge repair (p = 0.002) and chordal replacement (p = 0.038), after rupture to anterior leaflet chordae, recovered significantly better than specimens repaired by chordal transposition. There was no statistical difference in recovery between edge-to-edge repair and chordal replacement (p > 0.05). There was no statistical difference (p > 0.05) in the recovery of the pressure withstood by valves repaired by edge-to-edge repair and chordal replacement, after rupture of posterior leaflet chordae., Conclusion: These results showed that edge-to-edge repair and chordal replacement are well suited for the repair of both the anterior and posterior leaflets.

Lung hernia is a rare condition. Approximately one third of cases occur in the cervical position. We report a case of bilateral cervical lung hernia associated with neuralgic pain that was repaired using bovine pericardium and biological glue.

Background and Aim of the Study: The study aim was to understand the role of different mitral valve chordae tendineae, and how damage to them affects valve competence., Methods: A test apparatus was used to apply pressure to porcine mitral heart valves that were intact and have had selected chords severed. Anterior leaflet strut and marginal chords were selectively severed, as were posterior leaflet basal and marginal chords. Commissural chords were also severed., Results: Severing anterior leaflet marginal chords (p = 0.018) and commissural chords (p = 0.018) significantly reduced mitral valve competence. Severing posterior leaflet marginal and basal chords, and anterior leaflet strut chords, had no significant effect in reducing the pressures that the valves could withstand. Severing a mixture of posterior leaflet basal and marginal chords significantly reduced the pressure withstood by the valves (p = 0.004)., Conclusion: The study results confirmed that anterior leaflet marginal chords, but not strut chords, are vital for valve competence. Commissural chords were also shown to be vital for mitral valve competence. Several posterior leaflet chords had to be severed to affect mitral valve competence.

Traumatic chylothorax requires surgical intervention when conservative medical management fails to reduce chyle leakage. This usually entails thoracotomy or laparotomy. We report a case in which successful ligation of a torn thoracic duct was achieved using a video-assisted thoracoscopic technique.

A 21-year-old man presenting with a recurrent spontaneous haemothorax was found to have an osteochondroma arising out of the left 4th rib. This was penetrating the apical part of the heart. Surgical excision was uneventful.