Search

A 40 year old woman with cough and exertional dyspnoea was found to have a large right atrial myxoma by M mode and cross sectional echocardiography. Prolapse of the tumour into the right ventricle occurred during diastole with sufficient force to cause mechanical distortion of the interventricular septum. Septal motion became normal after surgical resection of the myxoma.

Eighteen patients (11 men and 7 women) with symptomatic second or third degree atrioventricular block underwent implantation of the rate-responsive RS4-SRT pacing system. Exercise tolerance in RS4 mode was compared to that in VVI mode by randomized double-blind treadmill stress testing. Following hospital discharge, RS4 function was assessed by repeat exercise testing and 24-hour Holter monitoring. Difficulty in obtaining satisfactory P-wave amplitudes at implantation (mean 3.1 +/- 1.5 mV) resulted in prolonged implantation times (mean 79.4 +/- 26.4 minutes). Following implantation, 10 patients (58%) showed a significant ventricular rate response to exercise, seven did not, and one remained in sinus rhythm. For responders, peak ventricular paced rate and double product were significantly greater in RS4 than in VVI mode, being 101.8 +/- 5.8 vs. 74.3 +/- 0.4 beats per minute and 20.1 +/- 2.9 vs. 15.5 +/- 3.7 beats per minute X mmHg X 10(-3), respectively (p less than 0.001). However, treadmill times (10.5 +/- 2.6 vs. 9.7 +/- 3.3 minutes) and work done (5.51 +/- 2.01 vs. 4.97 +/- 2.33 joules X 10(-5] were not significantly different (p = 0.22). Following hospital discharge, repeat exercise testing and 24-hour Holter monitoring demonstrated RS4 function in 11 of 16 and 15 of 18 patients, respectively. We conclude that, due to unreliable atrial sensing, the RS4-SRT pacing system does not provide the reliable rate-responsiveness required to improve exercise tolerance.

Combined rapid atrial flutter/fibrillation and recurrent ventricular tachycardia occurred in an 82 year old man with acute myocardial infarction. Both arrhythmias were promptly terminated by intravenous sotalol, suggesting another use for this unique drug in the absence of hypotension, heart block or cardiac failure.

One hundred and twenty-three patients underwent combined valve and coronary artery bypass surgery, between 1974 and 1985. Seventy patients had aortic valve replacement, 53 had mitral valve replacement; 63.4% were male and 45% were over 60 years (mean 59 +/- 2 years). Ischaemic cardiac arrest was used in 21 patients (Group I), cold crystalloid cardioplegia in 51 (Group II), and cold blood cardioplegia in 51 (Group III). Group III had a greater number of patients with poor preoperative functional status and left ventricular function. Early mortality was 19%, 17.6% and 11.7% in Groups I, II and III respectively (NS), and was not influenced by patients age, number of vessels with critical coronary artery disease and the type of the valve procedure. There was a significant decrease in the release of LDH and AST in Group III when compared with Group II (p less than 0.02 and p less than 0.01) respectively. The linearized rate of recurrence of angina (% per patient year) was 0.4, 0.95 and 0.07; and late mortality (% per 100 years) was 5.8, 3.2 and 2.6 in Groups I, II and III respectively. Patient survival and the quality of life has been improved since the introduction of cold blood cardioplegic protection.

Right ventricular overdrive pacing is an effective method for termination of ventricular tachycardia. This may be due to alteration in conduction rate, conduction pathways, or refractory periods of myocardial tissue. The procedure can be facilitated by antiarrhythmic drugs which increase tachycardia cycle length. Sotalol possesses beta-blocking action, has been shown to increase duration of action potentials and refractory periods throughout myocardial tissue and accessory pathways, and can suppress and prevent recurrent malignant ventricular arrhythmias. We describe two cases with ventricular tachycardia which were terminated transiently by cardioversion, but were resistant to various antiarrhythmic drugs. Right ventricular overdrive pacing was used in both cases, but was only effective after the administration of intravenous sotalol. We conclude that the unique properties of sotalol may make it especially effective in this context. Caution is required because of the hypotensive and negative inotropic actions of beta blockers, and possible acceleration of ventricular tachycardia by overdrive pacing.

A prognostic index for predicting significant coronary artery disease was established using multiple logistic regression analysis of clinical data from 643 patients with valvular heart disease who had undergone routine coronary arteriography before valve replacement. The index or equation obtained incorporated the presence of angina, a family history of ischaemic heart disease, age, cigarette smoking habits, mitral valve disease, sex, and electrocardiographic evidence of myocardial infarction. The equation was validated using prospective data from 387 patients with valvular disease and shown to enable almost a third of routine coronary arteriograms to be omitted while maintaining 95% sensitivity for patients with coronary artery disease. Similar analysis of the more detailed prospective data produced a second discriminant function incorporating diastolic blood pressure, total cigarettes smoked in life, the severity of angina, family history of ischaemic heart disease, age, current cigarette smoking habits, and the ratio of total to high density lipoprotein cholesterol. This method improved the discrimination between patients with and without coronary artery disease, allowing omission of 30% of routine coronary arteriograms with 100% sensitivity for patients with coronary disease and omission of 41% with a 96% sensitivity level.

Constrictive pericarditis developed in a 55 year old man two years after transmural myocardial infarction complicated by severe acute pericarditis. Pericardiectomy was successful. Although this very rare late complication of myocardial infarction has been reported as a sequela of frank anticoagulant induced haemopericardium, in this case there was no clinical evidence of such an association.

During attempted removal of an infected permanent pacemaker system, the electrode fractured, leaving the tined tip embedded in the wall of the left subclavian vein. The electrode tip was successfully removed using a Dotter basket retrieval kit.

The association between extent and duration of smoking habit and severity of coronary atheroma was examined in 387 patients undergoing routine coronary ateriography before valve replacement surgery. Total number of cigarettes smoked in life correlated significantly with severity of coronary artery disease (p less than 0.001) and number of coronary arteries with stenoses of 50% or more (p less than 0.001). Severity of coronary artery disease in current smokers was similar to that in former smokers. Multiple regression analysis showed diastolic blood pressure, cigarette consumption, age, ratio of total cholesterol to high density lipoprotein cholesterol, and history of angina to be the important predictors of severity of coronary artery disease. An estimate of the number of cigarettes smoked in life can be useful in identifying patients with coronary artery disease if used in conjunction with data on other important risk factors.

A 65 year old man with recurrent ventricular tachyarrhythmias post myocardial infarction developed dysarthria and visual hallucinations due to flecainide toxicity. A readily available assay is required for estimating serum flecainide levels in patients with diminished renal or hepatic function or failed arrhythmia suppression.

Prophylactic antibiotics are frequently prescribed for patients undergoing permanent pacemaker implantation even though data confirming their effectiveness are limited. Five hundred patients requiring elective permanent pacemaker implantation or generator replacement were prospectively randomized either to receive or not receive prophylactic antibiotic treatment at the time of implantation. The implantation site was treated with 10% povidone-iodine solution and 0.5% alcoholic chlorhexidine preoperatively. The wound were inspected for evidence of infection at 3 days and 1, 3, 6 and 12 months postimplantation. Three patients (two receiving prophylactic antibiotics and one no antibiotics) developed pacemaker pocket infection; Staphylococcus aureus was the pathogenic organism in each case (P = 0.56). Eighteen patients developed clinical evidence of superficial wound inflammation requiring antibiotic treatment but not pacemaker removal. Six had received prophylactic antibiotics and 12 had not (P = 0.27). We conclude that pacemaker pocket infection is unusual with careful preoperative skin preparation and close postoperative follow-up. Under these circumstances prophylactic antibiotic treatment is of no practical value.

Pain relief in acute myocardial infarction (AMI) by the beta-adrenoceptor antagonist, atenolol, was demonstrated by three separate studies. First, 18 patients were randomized to double-blind intravenous atenolol (5 mg) or saline immediately after admission, followed by oral atenolol (50 mg) or placebo 10 minutes later. In patients receiving atenolol, pain relief coincided with reduction in heart rate (HR), systolic blood pressure (SBP), and HR X SBP product (p less than 0.05); however, pain and these parameters were unchanged by placebo. The degree of pain relief was related to the reduction in cardiac work achieved (r = 0.725; p less than 0.001). A second open study involving 22 patients receiving intravenous atenolol (5 to 15 mg) early after AMI showed ischemic pain relief in 17 patients. They achieved a more significant reduction in HR X SBP product than those whose pain remained unchanged (p = 0.004). Finally, a retrospective study of 163 patients randomized to either atenolol or no beta blockade early after AMI revealed that patients receiving atenolol needed less opiate analgesia after admission (p less than 0.001). The safety of this therapy was illustrated by a decreased incidence of left heart failure and atrial fibrillation and no tendency to second- and third-degree heart block.

A 57 year old man required emergency coronary artery bypass surgery after dissection of the left main coronary artery during percutaneous transluminal coronary angioplasty. His symptoms recurred when the vein grafts became occluded. A dilatation device with the lowest profile was used to reduce the need for firm support from the guiding catheter during repeat percutaneous transluminal coronary angioplasty. The repeat procedure was successful in opening up the left circumflex coronary artery.

To determine the type and frequency of supraventricular arrhythmias in patients with mitral stenosis and sinus rhythm we studied 63 such patients, mean (sd) age 48.8 (8.2) years, by 24 hour ambulatory ECG monitoring. Thirty-five patients (55.6%) had supraventricular tachyarrhythmias. Twenty-five (39.7%) had paroxysmal atrial tachycardia, 14 (22.2%) atrial fibrillation, 8 (12.7%) multifocal atrial tachycardia and 5 atrial flutter. Ninety-five per cent (101) of episodes were asymptomatic and 96% non-sustained. Supraventricular premature beats occurred in 59 patients with couplets and triplets in 40 (63.5%) and 28 (44.4%), respectively. Frequent supraventricular premature beats, couplets, triplets and episodes of paroxysmal arrhythmias were commoner in patients greater than 50 years. Ectopic atrial rhythms with varying P wave morphology occurred in 12 patients (19%). Nine patients (14.3%) had suffered systemic embolic episodes. We conclude that supraventricular ectopic and tachyarrhythmias occur frequently in patients with mitral stenosis and sinus rhythm and that most paroxysms are non-sustained and asymptomatic.

The relationship between coronary risk factors and coronary artery disease in patients with valvular heart disease was studied prospectively in 387 consecutive patients undergoing routine coronary arteriography prior to valve replacement. Coronary artery disease was as common in patients with mitral valve disease (31.9%) as in those with aortic valve disease (26.8%). Although it occurs more frequently in patients with angina (45.7%) significant coronary artery disease is found in 19.2% (47 of 245) of those without angina (P less than 0.001), suggesting that the presence of angina alone is an unreliable indicator of significant coronary disease. The prevalence and severity of significant coronary artery disease increases progressively as the number of coronary risk factors also increase (P less than 0.001) but the prevalence is low (3%) in patients in whom both angina and coronary risk factors are absent. These findings suggest that preoperative coronary arteriography might be omitted in this latter group of patients.

A patient with sinus node dysfunction and absent right superior vena cava underwent stable temporary and permanent endocardial pacing via a left sided superior vena cava. Active fixation of the electrode and epicardial pacing were not necessary.

Several prognostic indices for predicting various aspects of coronary artery disease were significantly improved by the inclusion of psychosocial factors. 218 patients with valvular heart disease who had undergone routine coronary arteriography before valve replacement were studied in terms of cigarettes smoked, family history of ischaemic heart disease, HDL:cholesterol ratio, angina, sex, blood pressure and four psychosocial characteristics (i.e. social support, work stress, life events and Type A behavior). It was found that the psychosocial factors improved the preoperative predictive power of significant coronary artery disease on four criteria: previous history of hypertension, previous history of myocardial infarction, signs of peripheral vascular disease and ECG evidence of myocardial infarction.