Supravalvar aortic stenosis: unexpected findings at surgery.
Explore the source record for details and available documents.
Aortic Stenosis, Subvalvular↗
Biomedical subjects
R H Swanton
Publications and source records attributed to R H Swanton.
The incidence of significant pericardial effusion and tamponade following major aortic root surgery.
OBJECTIVE: To examine the hypothesis that the incidence of significant pericardial effusion following aortic root surgery is higher than anticipated after cardiac surgery. DESIGN: A retrospective data analysis. SETTING: A tertiary referral centre for cardiothoracic surgery. SUBJECTS: All patients undergoing aortic root surgery either with or without aortic valve replacement between January 1991 and July 1993. RESULTS: Three patients developed late cardiac tamponade (7-10 days post-operatively) and a further three developed clinically significant pericardial effusions as a result of post-pericardiotomy syndrome. The 31.6% (95% confidence limit: 12.5-56%) incidence of significant pericardial effusions following aortic root surgery is therefore significantly higher than anticipated after cardiac surgery (0.8-6). CONCLUSION: These data support the hypothesis that the incidence of significant pericardial effusion following aortic root surgery is higher than anticipated after cardiac surgery. We recommend that echocardiography is routinely performed during the post-operative period in these patients to exclude significant pericardial effusions.
Adult↗
Permanent pacing in patients with tricuspid valve replacements.
OBJECTIVE: To assess the incidence and complications of permanent pacing in patients who undergo tricuspid valve replacement. DESIGN: A retrospective study of records of patients who had a tricuspid valve replacement between 1978 and 1993 at the Middlesex hospital. RESULTS: 45 patients with tricuspid valve replacements were followed up for a total of 104 patient years. Ten patients (22%) required permanent pacing, five with epicardial leads and five with endocardial. Endocardial leads had significantly lower initial implantation thresholds and were associated with fewer complications. CONCLUSION: Patients undergoing tricuspid valve replacement frequently require permanent pacing. Endocardial or epicardial lead insertion should be considered at the time of tricuspid valve replacement.
Aged↗
How do the clinical findings in patients with pericardial effusions influence the success of aspiration?
OBJECTIVE: To identify features associated with success or failure of aspiration of pericardial effusion. METHOD: A retrospective analysis of 36 drainage procedures in 30 patients with pericardial effusion was performed using patient records and echocardiograms. RESULTS: Unsuccessful aspiration was associated with pericardial loculation but not with the seniority of the operator or the size and position of the effusion. Pericardiocentesis relieved symptoms of breathlessness in 21 of 26 patients who had a pericardial effusion suspected of causing dyspnoea. These 21 patients had few clinical or echocardiographic signs of classic tamponade. CONCLUSION: The paucity of abnormal physical or echocardiographic signs of tamponade in breathless patients with pericardial effusion does not exclude symptomatic benefit being derived from pericardiocentesis. Pericardial aspiration is safe in appropriate hands, although aspiration of loculated effusions may not be as successful as aspiration of non-loculated effusions.
Adolescent↗
Assessment of magnetic resonance velocity mapping of global ventricular function during dobutamine infusion in coronary artery disease.
BACKGROUND: Magnetic resonance imaging (MRI) is a versatile technique for examination of the cardiovascular system but only recently has assessment of myocardial ischaemia in coronary artery disease (CAD) become possible, for example by demonstrating abnormalities of regional ventricular contraction during stress. Global ventricular function during stress was assessed by MRI of aortic flow, which has not been previously attempted. DESIGN: Variables measured by MRI reflecting the effect of ischaemia on global ventricular function during dobutamine stress were correlated with thallium-201 myocardial perfusion tomography. PATIENTS: 10 normal controls and 25 patients with CAD. SETTING: Tertiary cardiac referral centre. METHODS: Novel MRI sequences and analysis systems were used to measure the following variables during staged dobutamine infusion to 20 micrograms/kg/min: stroke volume, cardiac output, cardiac power output, peak flow, peak flow acceleration, aortic back flow, and flow wave velocity. Heart rate, blood pressure, double product, and maximum tolerated dobutamine dose were also measured. Multiple regression analysis was used to compare changes during stress with 201TI tomography. RESULTS: All parameters except for stroke volume and diastolic blood pressure increased in the controls. In the patients with CAD a significant relation was shown between the extent of reversible ischaemia and the change in peak flow acceleration (P < 0.00001), peak flow (P = 0.002), cardiac power output (P = 0.036), maximum dobutamine dose (P = 0.039), and systolic blood pressure (P = 0.04). Peak flow acceleration accounted for 58.4% of the variation in reversible ischaemia, and after allowing for this, only cardiac power output remained independently predictive adding a further 4.2% to the model (adjusted r2 = 0.626). A decrease in peak flow acceleration with an increase in dobutamine infusion indicated moderate or severe ischaemia (chi 2 = 10.2, P = 0.017). CONCLUSION: MRI may be used to assess variables of aortic flow during stress, which includes acceleration with high temporal resolution. Peak flow acceleration was the most sensitive indicator of the effect of ischaemia on global ventricular function.
Adult↗
Coronary artery fistulas presenting with bacterial endocarditis.
Coronary artery fistulas are rare congenital malformations. Two cases presenting with bacterial endocarditis are described. Both were treated successfully by grafting of the coronary artery and ligation of the fistula.
Adult↗
A case of osteomyelitis secondary to endocarditis.
Explore the source record for details and available documents.
Endocarditis, Bacterial↗
Osteomyelitis and infective endocarditis.
Osteomyelitis is thought to occur as a complication of infectious endocarditis in as many as 6% of cases of endocarditis. We describe this association in three patients. Osteomyelitis may be difficult to diagnose in patients with endocarditis because symptoms such as fever, bone pain and stiffness are common to both illnesses, therefore physicians need to have a high index of suspicion to avoid missing this important complication. We recommend that patients with endocarditis and persistent or localized musculoskeletal symptoms should be investigated to exclude osteomyelitis. Plain radiographs can be normal in 50% of cases of osteomyelitis in the early stages or show only minor abnormalities, but bone scans are highly sensitive. We suggest that a bone scan is performed if radiography is unhelpful, since a diagnosis of osteomyelitis can effectively be excluded if the bone scan is normal. We advocate close follow-up of these patients with prolonged antibiotic treatment consisting of at least 6 weeks of intravenous therapy, and 3 months or longer of oral therapy.
Administration, Oral↗
Infected right atrial thrombus--an important but rare complication of central venous lines.
A case of infected right atrial thrombus is described. Right atrial thrombus is difficult to diagnose and is associated with a high mortality. When it is additionally infected, antibiotics alone are not sufficient treatment and the thrombus should be surgically removed.
Bacteremia↗
Secundum atrial septal defect repair: long-term surgical outcome and the problem of late mitral regurgitation.
This study examines the clinical and surgical outcome of a group of 55 patients (mean age 33 years) with secundum atrial septal defect who underwent surgical repair of this defect between 1981 and 1990. A group of 25 of these patients underwent late echocardiographic follow-up. Fifty-two patients underwent repair by direct suturing and three by patch closure. Surgical mortality was nil. There was one late death of a 58 year old who died from cardiac failure 4 years after surgery. Late postoperative morbidity consisted of two patients; one, age 63 at the time of surgery, required mitral and tricuspid valve replacement 6 years later and one, age 77 at surgery, developed cardiac failure 3 years later. Atrial fibrillation persisted in the six patients who had the rhythm before surgery and developed postoperatively in two patients aged 54 and 58. Two patients aged 49 and 57 developed immediate postoperative sinus node dysfunction requiring permanent pacing. The mean age at surgery of those six patients who suffered cardiac morbidity was 60 years. The patients with preoperative angiographic evidence of mitral valve prolapse were significantly older (P < 0.001) and had higher mean pulmonary artery pressures (P < 0.001) than patients with normal valves. There was no significant relationship between shunt size and mitral valve prolapse. Echocardiographic follow-up showed persistent mitral valve prolapse in all nine patients who developed the condition preoperatively. Five patients developed mitral valve prolapse with mitral regurgitation postoperatively, one of whom needed subsequent mitral and tricuspid valve replacement. These five patient were on average older (mean age 54) but the group was too small to prove significance. The follow-up data illustrate the current low mortality and morbidity associated with surgical closure of atrial septal defects. Late postoperative echocardiography had revealed not only that mitral valve prolapse persists in those patients who developed the condition pre-operatively but that new cases of mitral valve prolapse with mitral regurgitation can occur after atrial septal defect closure.
Adult↗
Magnetic resonance imaging during dobutamine stress in coronary artery disease.
Cine magnetic resonance imaging (MRI) provides a tomographic method of assessing regional ventricular function in any desired plane. It has not been possible to obtain adequate images during dynamic exercise, and this has limited its value in patients with coronary artery disease (CAD). Therefore, an infusion of dobutamine was used to study 25 patients with exertional chest pain and abnormal exercise electrocardiograms. Areas of abnormal wall motion were compared with areas of abnormal myocardial perfusion imaged by dobutamine thallium emission tomography and with coronary arteriography. Twenty-two patients had significant CAD. Twenty-one (96%) of these patients had reversible myocardial ischemia shown by dobutamine thallium tomography, and 20 (91%) had reversible wall motion abnormalities shown by dobutamine MRI. Comparison of abnormal segments of perfusion and wall motion showed 96% agreement at rest, 90% agreement during stress, and 91% agreement for the assessment of functional reversibility. The normalized magnetic resonance signal intensity of the ischemic segments showed a small but significant reduction when compared with that of normal segments (-67 units [9.2%]; p less than 0.05). Dobutamine infusion was well-tolerated, despite causing chest discomfort in 24 patients (96%). Nine patients (36%) developed a minor dysrhythmia that was usually ventricular premature complexes, but this did not limit infusion, and other side effects were mild. The short plasma half-life of dobutamine makes it ideal as a stress agent for imaging techniques (such as MRI), and these results suggest that it is more effective in the provocation of wall motion abnormalities than is dipyridamole in patients with CAD.
Adult↗
Propionibacterium acnes causing an aortic root abscess.
A case of endocarditis caused by Propionibacterium acnes associated with an aortic root abscess is presented. This supports the current opinion that aortic root abscesses are not necessarily associated with microorganisms of high virulence.
Abscess↗
Dobutamine thallium myocardial perfusion tomography.
Dobutamine has favorable properties for the pharmacologic manipulation of myocardial oxygen demand in the provocation of ischemia during the investigation of coronary artery disease. The value of dobutamine infusion for thallium myocardial perfusion tomography was assessed in 50 patients with exertional chest pain undergoing coronary arteriography. Dobutamine was infused in 5-min stages at incremental rates from 5 to 20 micrograms/kg per min or until limited by symptoms. The myocardium was divided into nine segments for analysis of perfusion. Thirty-nine of 40 patients with coronary artery disease had a reversible perfusion defect demonstrated by dobutamine thallium tomography (sensitivity 97%) and 8 of 10 patients with normal coronary arteries had normal myocardial perfusion (specificity 80%). These values were significantly better than the sensitivity and specificity of exercise electrocardiography (78% and 44%, respectively; p less than 0.01). There was a significant relation between the mean number of segments with abnormal perfusion and the number of diseased coronary vessels (0.6, 2.6, 4.4 and 6 segments in zero-, one-, two- and three-vessel disease, respectively; p less than 0.001). There was also a significant relation between the maximal tolerated dose of dobutamine and the treadmill exercise time (r = 0.56, p less than 0.001), but a wide range of exercise times was achieved in the 15- and 20-micrograms/kg per min groups, principally because of exercise limitation by noncardiac symptoms. Dobutamine infusion was well tolerated in all patients, including six with asthma. There were no significant arrhythmias or limiting symptoms other than chest pain.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Aortic root complications of infective endocarditis--influence on surgical outcome.
Fifty cases of aortic valve endocarditis during a 6-year period between 1982 and 1988 were reviewed. Twenty-three (46%) had aortic root complications by way of aortic root abscess or mycotic aneurysm in the perivalvular area. Patients with root complications were grouped into the aortic root abscess (ARA) group and those without into a non root abscess (NARA) group. Prosthetic valve endocarditis dominated in the ARA group (12 and four cases of prosthetic valve infection in the ARA and NARA groups, respectively; P less than 0.01). Surgical mortality was significantly higher at 13.6% in the ARA group as opposed to 2.2% in the NARA group (P less than 0.05). Post-operative aortic regurgitation was present in 8 (57%) of 14 patients in the ARA group surviving surgery but in only two (8.7%) of 23 patients in the NARA group (P less than 0.03). We conclude that aortic root complications are a frequent occurrence in aortic valve endocarditis, lead to an increased operative mortality and is associated with a high incidence of post-operative aortic regurgitation.
Abscess↗
Pedunculated left ventricular thrombus--report of two cases.
In two patients presenting with myocardial infarction, one with a subendocardial infarction and the second patient with a classic Q wave infarction, pedunculated left ventricular thrombi were detected in the course of subsequent routine cardiac catheterization. Both patients underwent successful surgical thrombectomy.
Cardiac Catheterization↗
Monophasic action potential recordings in response to rapid transient elevation of extracellular potassium and their modification by beta-adrenoceptor blockade in the anaesthetized dog.
1. Monophasic action potentials (MAPs) were recorded simultaneously from the endocardium and the epicardium in open-chested dogs (n = 16) during bolus intravenous injections of potassium chloride at 0.1 mmol/kg and 0.2 mmol/kg. MAP duration was measured at 90% repolarization. Local conduction was measured as the delay between the pacing artefact and upstroke of the MAP. 2. The animals were anaesthetized with alpha-chloralose and urethane. Heart block was created by atrioventricular nodal ablation with 0.1% (v/v) formalin. Infra-nodal pacing was established. 3. Bolus injections of potassium chloride at 0.1 mmol/kg shortened MAP duration. The effect was maximal at 15 s after the injection [epicardium: 171.5 +/- 3.0 (control) and 148.9 +/- 5.2 ms at 15 s (P less than 0.001); endocardium: 178.7 +/- 4.4 (control) and 165.6 +/- 5.3 ms (P less than 0.001)]. The shortening on the epicardium was significantly greater than on the endocardium (P less than 0.05). 4. Local conduction time showed no significant change [epicardium: 37.8 +/- 1.8 (control) and 41.2 +/- 2.4 at 15 s; endocardium: 41.1 +/- 1.6 (control) and 45.0 +/- 3.4 at 15 s]. 5. After beta-adrenoceptor blockade, MAP duration shortened, exhibiting a maximum effect at 20 s after a bolus injection of potassium chloride at 0.1 mmol/kg [epicardium: 184.7 +/- 7.1 (control) and 130.7 +/- 9.0 ms at 20 s (P less than 0.001); endocardium 192.0 +/- 7.4 (control) and 148.6 +/- 10.8 ms at 20 s (P less than 0.001)]. The greater shortening observed on the epicardial surface did not reach statistical significance.(ABSTRACT TRUNCATED AT 250 WORDS)
Action Potentials↗
Echocardiographic abnormalities in type IV mucopolysaccharidosis.
Cardiac involvement is well recognised in most forms of the mucopolysaccharidoses but there is poor documentation of abnormalities specific to Morquio's syndrome (type IV mucopolysaccharidosis). Ten patients with the classic form or type A Morquio's syndrome with a median age of 12.5 years underwent echocardiographic assessment. Abnormalities were detected in six (60%) cases with mitral valve involvement in five patients and aortic valve disease in four. One patient had severe mitral leaflet thickening to the point of mitral stenosis. Two patients had evidence for myocardial involvement by way of echocardiographic ventricular hypertrophy. The cardiac lesions were haemodynamically mild. A cardiac murmur was audible in only three of the six cases. It is concluded that there is a high prevalence of silent cardiac abnormalities in patients with Morquio's syndrome with predominantly left sided valve involvement. Echocardiography should be part of the assessment of these patients and bacterial endocarditis prophylaxis should be advised for those with cardiac abnormalities.
Adolescent↗
Pseudoxanthoma elasticum presenting with myocardial infarction.
A 31 year old man presented with an anterior myocardial infarction. He had a history of recurrent gastrointestinal bleeding of obscure cause since childhood and peripheral vascular disease. A clinical diagnosis of the type 1 dominant form of pseudoxanthoma elasticum was supported by histological data from skin biopsy.
Adult↗