Case Reports 257
Case Reports 1. Lethal Cardiac Tamponade due to Aortotomy Wound Dehiscence after Cardiac Valve Replacment: a forensic presentation F PATEL, DMJ Lecturer in Forensic Medicine, UMDS Guy's and St Thomas' Hospitals (University of London), London Bridge, London, England ABSTRACT Lethal cardiac tamponade due to aortotomy wound dehiscence after cardiac valve replacement (CVR) are apparently unreported in the recent literature. An uncommon example of delayed non-valvular lethal complication of CVR occurring in the early out-patient period is reported here. The forensic aspects of wound dehiscence in cardiovascular surgery for cardiac valve replacement are discussed, and complemented by a study of the fracture ends of suture material in wound breakdown associated with the suture failure.
INTRODUCTION
Sudden death may complicate any major surgical procedure and the mortality figures for CVR are estimated to be 2-5 per cent (Hawley et al., 1988). The cause of death may lie at the surgical operation site or it may be due to some cardiac pathology which is remote. These deaths, however, may be non-cardiac, either associated with the prosthetic valve replacement or due to a concomitant disease. The death may be categorized as occurring in one of three periods; intra-operative, early post-operative and delayed post-operative. In the case reported here, it was classified as an early complication, i.e. occurring within 30 days of the patient being discharged home (Edmunds et al., 1988; Gonzales-Lavin, 1989). Death in the intra-operative and early postoperative periods of CVR may attract medicolegal attention. A full post-mortem examination should be performed in all cases. There may be characteristic endocardial injury and in mitral valve replacement (MVR), for example, the
post-mortem examination of the heart may establish the exact nature of the surgical trauma (Hawley et al., 1988). The forensic concern might also be focused on the suture material and the technique employed for the closure of the aortotomy at the CVR operation, e.g. continuous suture versus interrupted sutures. The autopsy findings serve as a valuable adjunct to clinical CVR audit. The recommended guidelines for reporting morbidity and mortality after CVR have been published (Edmunds et al., 1988). The death in the case reported here was proved at autopsy to be nonvalvular. CASE REPORT
J.G. was a 42-year-{)ld man who underwent an aortic valve replacement (AVR) for severe regurgitation. He had had a history of heart murmurs for 17 years (ejection systolic and early diastolic radiating to the neck) and hypertension (BP 180/100 mml'Ig), but felt generally well. He was referred for surgery when deterioration of left ventricular function was detected on echocardiogram and severe regurgitation was confirmed by cardiac catheterisation, Although the aortic valve did not appear abnormal on the echocardiogram a bicuspid anomaly was suspected, because of maximal opening times with the ejection sound on the phonocardiogram. At operation, it was noted that the ascending aorta was mildly enlarged and the left ventricle dilated, consistent with
258 Meet Sci. Law (1992) Vol. 32, No.1
long-standing aortic regurgitation. The aortic valve was tricuspid with an abnormally situated non-coronary semilunar cusp (right posterior cusp) which was below the coronary cusps (anterior and left posterior semilunar cusps), this being the mechanism of regurgitation. The aortic valve was excised and replaced with a 23 mm monostrut (Bjork-Shiley) prosthesis which was secured using a non-absorbable 2/0 monofilament polypropylene (Prolene) interrupted suture. The routine supravalvar aortotomy was closed with continuous 4/0 Prolene suture. The intra-operative and immediate post-operative periods were uneventful and the patient made an excellent recovery, i.e. was discharged from hospital one week after his AVR operation. He was reviewed in the out-patient cardiology clinic four weeks after his hospi tal discharge and he complained only of minor musculo-skeletal wound pain. On examination, his exercise tolerance was normal and there was no evidence of cardiac failure. The pulse was regular and the blood pressure was 140nO mmHg. On auscultation, there were normal Bjork-Shiley valve sounds. An ECG confirmed a sinus rhythm. The chest X-ray was unremarkable and there was no change in the pre-existing cardiomegaly. A gradual discontinuation of Digoxin and long term anticoagulation with Warfarin maintenance was prescribed for him. He was considered to be fit to resume work after another month of recuperation, but was told to avoid strenuous exercise for a further two months. The next out-patient appointment was to coincide with the first anniversary of the CVR. Within 24 hours of the out-patient review he was found dead, sitting in his chair at the table in his home. There were no suspicious circumstances surrounding the death. Post·mortem examination At autopsy, the body was that of a well nourished middle aged Caucasian man. There was a healed sternotomy but otherwise the external examination was unremarkable. The internal examination revealed a massive tension haemopericardium. There were 10-
calized fibrous pericardial adhesions due to previous cardiac surgery. The heart weighed 710 gm and showed a concentrically hypertrophied and dilated left ventricle; the free wall and septum were both 2 em in thickness. The BjorkShiley prosthesis was correctly, sited and functional, and the sutures were all intact. There was no gross evidence of significant myocardial trauma. The root of the aorta showed dehiscence of the aortotomy wound. There was a fractured blue (copper pthalocyanine) synthetic suture
Figure 1. Root of aorta trimmed open to show the
fracture ends (arrowed)of the unravelled Prolene suture at the site of aortotomy wound dehiscence. A luminal view of the monostrut (Bjork-Shiley) prosthesis is presented.
which had unravelled at its midpoint
Case Reports 1. Lethal Cardiac Tamponade due to Aortotomy Wound Dehiscence after Cardiac Valve Replacment: a forensic presentation F PATEL, DMJ Lecturer in Forensic Medicine, UMDS Guy's and St Thomas' Hospitals (University of London), London Bridge, London, England ABSTRACT Lethal cardiac tamponade due to aortotomy wound dehiscence after cardiac valve replacement (CVR) are apparently unreported in the recent literature. An uncommon example of delayed non-valvular lethal complication of CVR occurring in the early out-patient period is reported here. The forensic aspects of wound dehiscence in cardiovascular surgery for cardiac valve replacement are discussed, and complemented by a study of the fracture ends of suture material in wound breakdown associated with the suture failure.
INTRODUCTION
Sudden death may complicate any major surgical procedure and the mortality figures for CVR are estimated to be 2-5 per cent (Hawley et al., 1988). The cause of death may lie at the surgical operation site or it may be due to some cardiac pathology which is remote. These deaths, however, may be non-cardiac, either associated with the prosthetic valve replacement or due to a concomitant disease. The death may be categorized as occurring in one of three periods; intra-operative, early post-operative and delayed post-operative. In the case reported here, it was classified as an early complication, i.e. occurring within 30 days of the patient being discharged home (Edmunds et al., 1988; Gonzales-Lavin, 1989). Death in the intra-operative and early postoperative periods of CVR may attract medicolegal attention. A full post-mortem examination should be performed in all cases. There may be characteristic endocardial injury and in mitral valve replacement (MVR), for example, the
post-mortem examination of the heart may establish the exact nature of the surgical trauma (Hawley et al., 1988). The forensic concern might also be focused on the suture material and the technique employed for the closure of the aortotomy at the CVR operation, e.g. continuous suture versus interrupted sutures. The autopsy findings serve as a valuable adjunct to clinical CVR audit. The recommended guidelines for reporting morbidity and mortality after CVR have been published (Edmunds et al., 1988). The death in the case reported here was proved at autopsy to be nonvalvular. CASE REPORT
J.G. was a 42-year-{)ld man who underwent an aortic valve replacement (AVR) for severe regurgitation. He had had a history of heart murmurs for 17 years (ejection systolic and early diastolic radiating to the neck) and hypertension (BP 180/100 mml'Ig), but felt generally well. He was referred for surgery when deterioration of left ventricular function was detected on echocardiogram and severe regurgitation was confirmed by cardiac catheterisation, Although the aortic valve did not appear abnormal on the echocardiogram a bicuspid anomaly was suspected, because of maximal opening times with the ejection sound on the phonocardiogram. At operation, it was noted that the ascending aorta was mildly enlarged and the left ventricle dilated, consistent with
258 Meet Sci. Law (1992) Vol. 32, No.1
long-standing aortic regurgitation. The aortic valve was tricuspid with an abnormally situated non-coronary semilunar cusp (right posterior cusp) which was below the coronary cusps (anterior and left posterior semilunar cusps), this being the mechanism of regurgitation. The aortic valve was excised and replaced with a 23 mm monostrut (Bjork-Shiley) prosthesis which was secured using a non-absorbable 2/0 monofilament polypropylene (Prolene) interrupted suture. The routine supravalvar aortotomy was closed with continuous 4/0 Prolene suture. The intra-operative and immediate post-operative periods were uneventful and the patient made an excellent recovery, i.e. was discharged from hospital one week after his AVR operation. He was reviewed in the out-patient cardiology clinic four weeks after his hospi tal discharge and he complained only of minor musculo-skeletal wound pain. On examination, his exercise tolerance was normal and there was no evidence of cardiac failure. The pulse was regular and the blood pressure was 140nO mmHg. On auscultation, there were normal Bjork-Shiley valve sounds. An ECG confirmed a sinus rhythm. The chest X-ray was unremarkable and there was no change in the pre-existing cardiomegaly. A gradual discontinuation of Digoxin and long term anticoagulation with Warfarin maintenance was prescribed for him. He was considered to be fit to resume work after another month of recuperation, but was told to avoid strenuous exercise for a further two months. The next out-patient appointment was to coincide with the first anniversary of the CVR. Within 24 hours of the out-patient review he was found dead, sitting in his chair at the table in his home. There were no suspicious circumstances surrounding the death. Post·mortem examination At autopsy, the body was that of a well nourished middle aged Caucasian man. There was a healed sternotomy but otherwise the external examination was unremarkable. The internal examination revealed a massive tension haemopericardium. There were 10-
calized fibrous pericardial adhesions due to previous cardiac surgery. The heart weighed 710 gm and showed a concentrically hypertrophied and dilated left ventricle; the free wall and septum were both 2 em in thickness. The BjorkShiley prosthesis was correctly, sited and functional, and the sutures were all intact. There was no gross evidence of significant myocardial trauma. The root of the aorta showed dehiscence of the aortotomy wound. There was a fractured blue (copper pthalocyanine) synthetic suture
Figure 1. Root of aorta trimmed open to show the
fracture ends (arrowed)of the unravelled Prolene suture at the site of aortotomy wound dehiscence. A luminal view of the monostrut (Bjork-Shiley) prosthesis is presented.
which had unravelled at its midpoint
