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C Munsch

Publications and source records attributed to C Munsch.

15 recordsLinked to original sources
PubMed2005

Mitral repair best practice: proposed standards.

OBJECTIVES: To define best practice standards for mitral valve repair surgery. DESIGN: Development of standards for process and outcome by consensus. SETTING: Multidisciplinary panel of surgeons, anaesthetists, and cardiologists with interests and expertise in caring for patients with severe mitral regurgitation. MAIN OUTCOME MEASURES: Standards for best practice were defined including the full spectrum of multidisciplinary aspects of care. RESULTS: 19 criteria for best practice were defined including recommendations on surgical training, intraoperative transoesophageal echocardiography, surgery for atrial fibrillation, audit, and cardiology and imaging issues. CONCLUSIONS: Standards for best practice in mitral valve repair were defined by multidisciplinary consensus. This study gives centres undertaking mitral valve repair an opportunity to benchmark their care against agreed standards that are challenging but achievable. Working towards these standards should act as a stimulus towards improvements in care.

Atrial Fibrillation↗
PubMed2001

Effect of radial artery harvesting on tissue perfusion and function of the hand.

This study was designed to measure the degree to which hand and forearm blood flow is reduced following harvesting of the radial artery in myocardial revascularization surgery and determine whether there is an effect on hand function. Twenty patients who had the radial artery used for myocardial revascularization underwent bilateral blood flow assessment of hands and forearms using Technetium-99m human serum albumin and clinical evaluation of hand function. Mean tissue perfusion in ml/100 ml/min +/- SD was as follows: donor hand 21.9 +/- 5.6, non-donor hand 25.5 +/- 6.1 (P = 0.00043), donor arm (hand and forearm) 17.5 +/- 3.7 and non-donor arm (hand and forearm) 21 +/- 5.1 (P = 0.000681). No clinical evidence of hand claudication was detected. This study suggests that removal of the radial artery reduces the tissue perfusion of the hand and forearm but does not affect hand function in the short term. The use of radial artery grafts in patients at risk of developing peripheral vascular disease should be carefully considered

Adult↗
PubMed1998

Unruptured aneurysm of the left sinus of Valsalva extending into the left ventricular outflow tract: presentation and imaging.

The symptomatic presentation of an unruptured sinus of Valsalva aneurysm is rare. A 48 year old man with a history of treated hypothyroidism, and a five year history of ileocolonic Crohn's disease of chronic low grade activity presented with a profound left hemiplegia. He was in sinus rhythm and normotensive. Cardiac auscultation was repeatedly normal. Computed tomography of the head performed early in the course of the illness was reported as normal. Duplex Doppler examination of the carotid arteries performed six months later revealed no significant atheroma. There was complete resolution of the neurological deficit over a period of months. A year later he presented with chest pain suggestive of myocardial ischaemia. Computed tomography, magnetic resonance imaging, transthoracic and transoesophageal echocardiography, and cardiac catheterisation pointed to a sinus of Valsalva aneurysm protruding into the left ventricular outflow tract. In view of the previous neurological event and ongoing chest pain suggestive of myocardial ischaemia, the lesion was resected. The patient made a good recovery and postoperative transoesophageal echocardiography showed normal aortic valve function with no residual regurgitation. This is the first reported case of pure left ventricular outflow tract extension of an unruptured left sinus aneurysm. The presentation with ischaemic cardiac pain does not seem to be explained by conventional mechanisms.

Aortic Aneurysm↗
PubMed1993

Disability and distress following cardiac surgery in patients over 70 years of age.

We have reviewed the outcome in a consecutive series of 254 patients over the age of 70 undergoing cardiac surgery between 1987-89. Of the patients, 62% were male and the median age was 73 years. Operations included: coronary bypass 57%, valve replacement 26%, combinations 14% and other procedures 3%. The hospital mortality was 7.5% and late mortality was 13.8%. Complications included: intraaortic balloon 6%, resternotomy for bleeding 4%, permanent pacing 3%, chest infection 14%, tracheostomy 5%, major cerebrovascular events 3% and minor 4%. Eighty-two percent left the intensive care unit within 24 h and 89% left hospital within 8 days. Two questionnaires (York University) were sent to 207 patients believed to be alive in order to evaluate the change in their quality of life following surgery. Of the 207 questionnaires 197 (95%) were returned, 7 of which were from relatives of patients who had died and 7 were incomplete. The responses of 183 assessable patients (at a mean follow-up of 36 months) were converted into Rosser disability (I-VIII) and distress (A-D) groups. There was a decrease in disability and distress in 60% and 67%, respectively, no change in 34% and 30% and deterioration in 6% and 3%. Cardiac surgery can be carried out in elderly patients with an acceptable early morbidity and mortality, and although many patients show sustained improvement in their quality of life, this was not demonstrated in about a third of patients. As the emphasis in the elderly should be on quality of life we ought to continue to concentrate on careful selection in this age group.

Aged↗
PubMed1992

Cardiac denervation in the calf using cryoablation: functional evidence and regional tissue catecholamine content.

Twenty-six calves were subjected to a technique of cryoablation in order to establish an animal model of complete cardiac denervation. All 26 survived the procedure, and 20 were alive to be re-evaluated 2-4 weeks later. Mean heart rate in the denervated animals rose from 77 +/- 7.8 beats/min to 102 +/- 16.4 (P less than 0.01). Cryoablation abolished the heart rate responses to electrical stimulation of the vagus nerve and thoracic sympathetic trunk. The reduction in myocardial noradrenaline concentrations averaged 99% in the right atrium, 90% in the left atrium, 85% in the right ventricle and 90% in the left ventricle, when compared with tissue obtained from control animals. Cryoablation is a relatively simple means of accomplishing complete functional cardiac denervation in the calf. On the basis of the observed change in heart rate, the calf model appears to be more comparable with human heart transplant recipients than the dog.

Animals↗
PubMed1991

Aprotinin used in emergency coronary operation after streptokinase treatment.

We describe a patient with evolving myocardial infarction who underwent emergency intracoronary thrombolysis followed by immediate coronary artery grafting. Aprotinin was administered intraoperatively to control the potential bleeding problems associated with thrombolysis. Total postoperative blood loss was 260 mL. The case illustrates a further use for aprotinin in cardiac operations when excessive bleeding is anticipated.

Aprotinin↗
PubMed1991

Pericardial haemorrhage causing right atrial compression after cardiac surgery: role of transoesophageal echocardiography.

After cardiac surgery transoesophageal echocardiography showed a large thrombus compressing the right atrium in three hypotensive patients. No satisfactory images were obtained by transthoracic imaging, which is often difficult in ventilated patients after cardiac surgery. Transoesophageal echocardiography, however, provided rapid diagnostic information and permitted prompt surgical intervention.

Aged↗
PubMed1991

Blood cardioplegia.

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Blood Chemical Analysis↗
PubMed1991

Absence of particle-induced coronary vasoconstriction during cardioplegic infusion: is it desirable to use a microfilter in the infusion line?

Many cardiac surgical units now use a microfilter in the infusion line for delivery of crystalloid cardioplegic solution to protect against the potential hazards of particulate contamination of cardioplegic solution. The aim of this group of studies was to determine the effects of particulate contamination of cardioplegic solutions, in order to establish whether a microfilter is needed in the infusion line. Total particle counts performed on two commercial cardioplegic solutions were low, but there were sufficient particles greater than 10 microns in diameter to cause coronary vasoconstriction. In isolated rat hearts a 20-minute infusion of St. Thomas' Hospital cardioplegic solution produced a progressive reduction in coronary flow, which was not prevented by the inclusion of a 0.8 micron filter in the infusion line. Two studies were performed on canine hearts to determine the effects of unfiltered cardioplegic solution on coronary vascular resistance. In the first, cardioplegic solution at 20 degrees C was infused for 20 minutes at a constant pressure of 50 mm Hg and flow rate was measured. In the second, the same solution at 4 degrees C was infused at a constant flow rate for 2 1/2 minutes and the infusion pressure was measured. In neither study did coronary vascular resistance rise. A final clinical study involving patients undergoing coronary bypass surgery compared the effects on coronary resistance of infusion at a constant flow of filtered versus unfiltered cardioplegic solution (n = 10 in each group). There was a similar rise in coronary perfusion pressure in both groups during the infusion. We conclude that there is insufficient evidence of particle-induced coronary vasoconstriction to justify the expense of a microfilter in the cardioplegic infusion line.

Animals↗
PubMed1989

The impaired tolerance of the recently infarcted rat heart to cardioplegic arrest: the protective effect of orotic acid.

After myocardial infarction, a reduced mass of non-infarcted myocardium remains to maintain cardiac output. This acutely stressed, non-infarcted myocardium exhibits many metabolic disturbances, and undergoes a process of acute hypertrophy. These stress-induced disturbances may reduce the tolerance of the heart to the global ischaemia of cardioplegic arrest and may explain the increased mortality and morbidity associated with cardiac surgery in patients with recent myocardial infarction. We postulated that orotic acid, a pyrimidine precursor which augments the rate of protein synthesis during hypertrophy, might improve the response of the recently infarcted heart to cardioplegic arrest. Myocardial infarction was induced in rats by coronary ligation, and after 2 days or 3 days the hearts were excised and perfused on the working heart apparatus. After measurement of work capacity, the hearts underwent 1 hour of hypothermic cardioplegic arrest. Post-arrest function was then measured and expressed as a percentage of the pre-arrest value. A group of sham-operated, non-infarcted hearts served as controls. There were two distinct findings: (1) when subjected to hypothermic cardioplegic arrest 2 days after myocardial infarction, hearts recovered only 49% of pre-arrest function, compared with 80% recovery in non-infarcted controls (P less than 0.001). Three days after infarction, recovery had improved to 68% (P less than 0.01 vs. 2 days, P less than 0.05 vs. non-infarcted). (2) Treatment with oral orotic acid following infarction augmented recovery from cardioplegic arrest to 83%, 2 days after infarction (P less than 0.001 vs. untreated) and to 87%, 3 days after infarction (P less than 0.01 vs. untreated).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

A comparison of heat exchangers for blood cardioplegia.

During open heart surgery, myocardial protection provided by oxygenated blood-based cardioplegia is superior to that provided by non-oxygenated crystalloid cardioplegia. However, the widespread use of blood cardioplegia has been limited by the cost and complexity of the associated cooling and delivery systems. The performance of a simple system--a polyethylene coil immersed in ice--has been compared with three systems incorporating specialized, water-jacketed heat exchangers: Buckberg Shiley, Shiley BCD and Bentley HE-100. Blood was diluted to a haematocrit of 22% and delivered to each cooling system at flow rates of 200-500 mL/min and temperatures of 25 degrees C and 30 degrees C. Cooling water at 0-1 degree C was supplied to the heat exchangers at flow rates of 2, 4, and 6 L/min. Performance was measured by comparing the blood outflow temperatures at the same inflow temperature under a variety of test conditions which simulated those occurring in clinical practice. All cooling systems, except the Buckberg Shiley, were able consistently to cool blood cardioplegia adequately (below 10 degrees C), but the ice coil was the most effective. The heat exchanger systems are 3-4 times more expensive than the ice coil and require an external source of cold water. Thus the ice coil system has the advantages of simplicity, efficiency, and economy.

Heart Arrest, Induced↗